U.S. patent application number 14/848557 was filed with the patent office on 2016-01-07 for surgical instrument with wireless communication between control unit and remote sensor.
The applicant listed for this patent is Ethicon Endo-Surgery, Inc.. Invention is credited to James R. Giordano, Frederick E. Shelton, IV, Jeffrey S. Swayze.
Application Number | 20160000437 14/848557 |
Document ID | / |
Family ID | 46275961 |
Filed Date | 2016-01-07 |
United States Patent
Application |
20160000437 |
Kind Code |
A1 |
Giordano; James R. ; et
al. |
January 7, 2016 |
SURGICAL INSTRUMENT WITH WIRELESS COMMUNICATION BETWEEN CONTROL
UNIT AND REMOTE SENSOR
Abstract
A surgical instrument, such as an endoscopic or laparoscopic
instrument. The surgical instrument may comprise an end effector
comprising at least one sensor. The surgical instrument may also
comprise an electrically conductive shaft having a distal end
connected to the end effector wherein the sensor is electrically
insulated from the shaft. The surgical instrument may also comprise
a handle connected to a proximate end of the shaft. The handle may
comprise a control unit electrically coupled to the shaft such that
the shaft radiates signals as an antenna from the control unit to
the sensor and receives radiated signals from the sensor. Other
components electrically coupled to the shaft may also radiate the
signals.
Inventors: |
Giordano; James R.;
(Milford, OH) ; Swayze; Jeffrey S.; (West Chester,
OH) ; Shelton, IV; Frederick E.; (Hillsboro,
OH) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Ethicon Endo-Surgery, Inc. |
Cincinnati |
OH |
US |
|
|
Family ID: |
46275961 |
Appl. No.: |
14/848557 |
Filed: |
September 9, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14559224 |
Dec 3, 2014 |
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14848557 |
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14176671 |
Feb 10, 2014 |
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14559224 |
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13118259 |
May 27, 2011 |
8684253 |
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14176671 |
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11651807 |
Jan 10, 2007 |
8459520 |
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13118259 |
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Current U.S.
Class: |
227/181.1 ;
227/176.1; 53/432; 53/440 |
Current CPC
Class: |
A61B 17/068 20130101;
A61B 2562/028 20130101; A61B 34/30 20160201; A61B 2017/2927
20130101; A61B 17/072 20130101; A61B 2090/065 20160201; A61B
2017/00212 20130101; A61B 2017/00398 20130101; A61B 17/32 20130101;
A61B 2017/00221 20130101; A61B 17/00234 20130101; A61B 2017/320093
20170801; A61B 2017/00473 20130101; A61B 17/295 20130101; A61B
2034/2072 20160201; A61B 90/98 20160201; A61B 2017/2943 20130101;
A61B 2017/320095 20170801; A61B 2017/07278 20130101; A61B 2090/0811
20160201; A61B 2017/00039 20130101; A61B 2017/00477 20130101; A61B
2017/07285 20130101; A61B 2017/00362 20130101; B65B 5/04 20130101;
A61B 17/105 20130101; A61B 17/07207 20130101; A61B 2017/00022
20130101; A61B 2017/320097 20170801; A61B 2034/302 20160201; A61B
2090/0814 20160201; A61B 2017/07271 20130101; A61B 2034/2053
20160201; A61B 17/1222 20130101; A61B 17/320092 20130101; B65B
55/18 20130101; A61B 34/71 20160201; A61B 2017/00685 20130101; A61B
2017/07214 20130101; A61B 2017/320094 20170801; B65B 55/16
20130101; A61B 2017/00734 20130101; A61B 2034/2059 20160201; A61B
50/36 20160201 |
International
Class: |
A61B 17/10 20060101
A61B017/10; B65B 55/18 20060101 B65B055/18; B65B 5/04 20060101
B65B005/04; B65B 55/16 20060101 B65B055/16; A61B 17/32 20060101
A61B017/32; A61B 17/068 20060101 A61B017/068 |
Claims
1. A surgical instrument comprising: an end effector comprising at
least one sensor; an electrically conductive shaft having a distal
end connected to the end effector wherein the sensor is
electrically insulated from the shaft; and a handle connected to a
proximate end of the shaft, the handle housing a control unit,
wherein the control unit is electrically coupled to the shaft such
that the shaft is configured to radiate signals from the control
unit to the sensor and to receive radiated signals from the
sensor.
2. The surgical instrument of claim 1, wherein the handle further
houses: a motor in communication with the control unit and for
powering the end effector; and a battery for powering the
motor.
3. The surgical instrument of claim 1, wherein the at least one
sensor comprises a magnetoresistive sensor.
4. The surgical instrument of claim 1, wherein the at least one
sensor comprises a pressure sensor.
5. The surgical instrument of claim 1, wherein the at least one
sensor comprises a RFID sensor.
6. The surgical instrument of claim 1, wherein the at least one
sensor comprises a MEMS sensor.
7. The surgical instrument of claim 1, wherein the at least one
sensor comprises an electromechanical sensor.
8. The surgical instrument of claim 1, wherein the at least one
sensor is connected to a plastic cartridge of the end effector.
9. The surgical instrument of claim 1, wherein the end effector
comprises an electrically conductive component coupled to the
shaft, wherein the electrically conductive component is configured
to radiate data signals to and from the sensor.
10. The surgical instrument of claim 1, wherein the surgical
instrument comprises an endoscopic surgical instrument.
11. The system of claim 1, wherein the surgical instrument
comprises a cutting and fastening surgical instrument.
12. The surgical instrument of claim 11, wherein the end effector
comprises a cutting instrument.
13. The surgical instrument of claim 12, wherein the end effector
comprises a plastic cartridge and the at least one sensor is
disposed in the cartridge.
14. A surgical instrument comprising: an end effector comprising at
least one sensor; an electrically conductive shaft having a distal
end connected to the end effector wherein the sensor is
electrically insulated from the shaft; and a control unit
electrically coupled to the shaft such that the shaft is configured
to radiate signals from the control unit to the sensor and to
receive radiated signals from the sensor.
15. The surgical instrument of claim 14, further comprising: a
motor in communication with the control unit and for powering the
end effector; and a battery for powering the motor
16. The surgical instrument of claim 14, wherein the at least one
sensor is connected to a plastic cartridge of the end effector.
17. The surgical instrument of claim 14, wherein the end effector
comprises an electrically conductive component coupled to the
shaft, wherein the electrically conductive component is configured
to radiate data signals to and from the sensor.
18. The surgical instrument of claim 17, wherein the end effector
comprises a plastic staple cartridge and the at least one sensor is
disposed in the staple cartridge.
19. A surgical instrument comprising: an end effector comprising at
least one sensor; an electrically conductive shaft having a distal
end connected to the end effector, wherein the sensor is
electrically coupled to the shaft; and a control unit electrically
insulated from the shaft such that the shaft is configured to
radiate signals from the sensor to the control unit and to receive
radiated signals from the control unit.
20. A method comprising: obtaining a surgical instrument, wherein
the surgical instrument comprises: an end effector comprising at
least one sensor; a shaft having a distal end connected to the end
effector wherein the sensor is electrically insulated from the
shaft; and a control unit electrically coupled to the shaft such
that the shaft is configured to radiate signals from the control
unit to the sensor and to receive radiated signals from the sensor;
sterilizing the surgical instrument; and storing the surgical
instrument in a sterile container.
21. The method of claim 20, further comprising remotely programming
the control unit while the instrument is in the sterile container.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a continuation application
claiming priority under 35 U.S.C. .sctn.120 to U.S. patent
application Ser. No. 14/559,224, entitled SURGICAL INSTRUMENT WITH
WIRELESS COMMUNICATION BETWEEN CONTROL UNIT AND REMOTE SENSOR,
filed Dec. 3, 2014, now U.S. Patent Application Publication No.
2015/0090762, which is a continuation application claiming priority
under 35 U.S.C. .sctn.120 to U.S. patent application Ser. No.
14/176,671, entitled SURGICAL INSTRUMENT WITH WIRELESS
COMMUNICATION BETWEEN A CONTROL UNIT OF A ROBOTIC SYSTEM AND REMOTE
SENSOR, filed Feb. 10, 2014, now U.S. Patent Application
Publication No. 2014/0171966, which is a continuation application
claiming priority under 35 U.S.C. .sctn.120 to U.S. patent
application Ser. No. 13/118,259, entitled SURGICAL INSTRUMENT WITH
WIRELESS COMMUNICATION BETWEEN A CONTROL UNIT OF A ROBOTIC SYSTEM
AND REMOTE SENSOR, filed May 27, 2011, which issued on Apr. 1, 2014
as U.S. Pat. No. 8,684,253, which is a continuation-in-part
application claiming priority under 35 U.S.C. .sctn.120 to U.S.
patent application Ser. No. 11/651,807, entitled SURGICAL
INSTRUMENT WITH WIRELESS COMMUNICATION BETWEEN CONTROL UNIT AND
REMOTE SENSOR, filed Jan. 10, 2007, which issued on Jun. 11, 2013
as U.S. Pat. No. 8,459,520, the entire disclosures of which are
hereby incorporated by reference herein.
[0002] The above listed application are related to the following
U.S. patent applications, filed Jan. 10, 2007, which are also
incorporated herein by reference in their respective
entireties:
[0003] (1) U.S. patent application Ser. No. 11/651,715, entitled
SURGICAL INSTRUMENT WITH WIRELESS COMMUNICATION BETWEEN CONTROL
UNIT AND SENSOR TRANSPONDERS, now U.S. Pat. No. 8,652,120;
[0004] (2) U.S. patent application Ser. No. 11/651,806, entitled
SURGICAL INSTRUMENT WITH ELEMENTS TO COMMUNICATE BETWEEN CONTROL
UNIT AND END EFFECTOR, now U.S. Pat. No. 7,954,682;
[0005] (3) U.S. patent application Ser. No. 11/651,768, entitled
PREVENTION OF CARTRIDGE REUSE IN A SURGICAL INSTRUMENT, now U.S.
Pat. No. 7,721,931;
[0006] (4) U.S. patent application Ser. No. 11/651,771, entitled
POST-STERILIZATION PROGRAMMING OF SURGICAL INSTRUMENTS, now U.S.
Pat. No. 7,738,971;
[0007] (5) U.S. patent application Ser. No. 11/651,788, entitled
INTERLOCK AND SURGICAL INSTRUMENT INCLUDING SAME, now U.S. Pat. No.
7,721,936; and
[0008] (6) U.S. patent application Ser. No. 11/651,785, entitled
SURGICAL INSTRUMENT WITH ENHANCED BATTERY PERFORMANCE, now U.S.
Pat. No. 7,900,805.
BACKGROUND
[0009] Known surgical staplers include an end effector that
simultaneously makes a longitudinal incision in tissue and applies
lines of staples on opposing sides of the incision. The end
effector includes a pair of cooperating jaw members that, if the
instrument is intended for endoscopic or laparoscopic applications,
are capable of passing through a cannula passageway. One of the jaw
members receives a staple cartridge having at least two laterally
spaced rows of staples. The other jaw member defines an anvil
having staple-forming pockets aligned with the rows of staples in
the cartridge. The instrument includes a plurality of reciprocating
wedges which, when driven distally, pass through openings in the
staple cartridge and engage drivers supporting the staples to
effect the firing of the staples toward the anvil.
FIGURES
[0010] Various embodiments of the present invention are described
herein by way of example in conjunction with the following figures
wherein:
[0011] FIGS. 1 and 2 are perspective views of a surgical instrument
according to various embodiments of the present invention;
[0012] FIGS. 3-5 are exploded views of an end effector and shaft of
the instrument according to various embodiments of the present
invention;
[0013] FIG. 6 is a side view of the end effector according to
various embodiments of the present invention;
[0014] FIG. 7 is an exploded view of the handle of the instrument
according to various embodiments of the present invention;
[0015] FIGS. 8 and 9 are partial perspective views of the handle
according to various embodiments of the present invention;
[0016] FIG. 10 is a side view of the handle according to various
embodiments of the present invention;
[0017] FIGS. 11, 13-14, 16, and 22 are perspective views of a
surgical instrument according to various embodiments of the present
invention;
[0018] FIGS. 12 and 19 are block diagrams of a control unit
according to various embodiments of the present invention;
[0019] FIG. 15 is a side view of an end effector including a sensor
transponder according to various embodiments of the present
invention;
[0020] FIGS. 17 and 18 show the instrument in a sterile container
according to various embodiments of the present invention;
[0021] FIG. 20 is a block diagram of the remote programming device
according to various embodiments of the present invention;
[0022] FIG. 21 is a diagram of a packaged instrument according to
various embodiments of the present invention;
[0023] FIGS. 23 and 24 are perspective views of a surgical
instrument according to various embodiments of the present
invention;
[0024] FIGS. 25-27 are exploded views of an end effector and shaft
of the instrument according to various embodiments of the present
invention;
[0025] FIG. 28 is a side view of the end effector according to
various embodiments of the present invention;
[0026] FIG. 29 is an exploded view of the handle of the instrument
according to various embodiments of the present invention;
[0027] FIGS. 30 and 31 are partial perspective views of the handle
according to various embodiments of the present invention;
[0028] FIG. 32 is a side view of the handle according to various
embodiments of the present invention;
[0029] FIG. 33 is a schematic block diagram of one embodiment of a
control unit for a surgical instrument according to various
embodiments of the present invention;
[0030] FIG. 34 is a schematic diagram illustrating the operation of
one embodiment of the control unit in conjunction with first and
second sensor elements for a surgical instrument according to
various embodiments of the present invention;
[0031] FIG. 35 illustrates one embodiment of a surgical instrument
comprising a first element located in a free rotating joint portion
of a shaft of the surgical instrument;
[0032] FIG. 36 illustrates one embodiment of a surgical instrument
comprising sensor elements disposed at various locations on a shaft
of the surgical instrument;
[0033] FIG. 37 illustrates one embodiment of a surgical instrument
where a shaft of the surgical instrument serves as part of an
antenna for a control unit;
[0034] FIGS. 38 and 39 are perspective views of a surgical
instrument according to various embodiments of the present
invention;
[0035] FIG. 40A is an exploded view of the end effector according
to various embodiments of the present invention;
[0036] FIG. 40B is a perspective view of the cutting instrument of
FIG. 40A;
[0037] FIGS. 41 and 42 are exploded views of an end effector and
shaft of the instrument according to various embodiments of the
present invention;
[0038] FIG. 43 is a side view of the end effector according to
various embodiments of the present invention;
[0039] FIG. 44 is an exploded view of the handle of the instrument
according to various embodiments of the present invention;
[0040] FIGS. 45 and 46 are partial perspective views of the handle
according to various embodiments of the present invention;
[0041] FIG. 47 is a side view of the handle according to various
embodiments of the present invention;
[0042] FIGS. 48 and 49 illustrate a proportional sensor that may be
used according to various embodiments of the present invention;
[0043] FIG. 50 is a block diagram of a control unit according to
various embodiments of the present invention;
[0044] FIGS. 51-53 and FIG. 63 are perspective views of a surgical
instrument according to various embodiments of the present
invention;
[0045] FIG. 54 is a bottom view of a portion of a staple cartridge
according to various embodiments;
[0046] FIGS. 55 and 57 are circuit diagrams of a transponder
according to various embodiments;
[0047] FIG. 56 is a bottom view of a portion of a staple cartridge
according to various embodiments;
[0048] FIG. 58 is a perspective view of a staple cartridge tray
according to various embodiments;
[0049] FIGS. 59 and 60 are circuit diagrams of a transponder
according to various embodiments;
[0050] FIG. 61 is a flow diagram of a method of preventing reuse of
a staple cartridge in surgical instrument according to various
embodiments;
[0051] FIG. 62 is a block diagram of a circuit for preventing
operation of the motor according to various embodiments;
[0052] FIGS. 64 and 65 are perspective views of a surgical cutting
and fastening instrument according to various embodiments of the
present invention;
[0053] FIG. 66A is an exploded view of the end effector according
to various embodiments of the present invention;
[0054] FIG. 66B is a perspective view of the cutting instrument of
FIG. 66A;
[0055] FIGS. 67 and 68 are exploded views of an end effector and
shaft of the instrument according to various embodiments of the
present invention;
[0056] FIG. 69 is a side view of the end effector according to
various embodiments of the present invention;
[0057] FIG. 70 is an exploded view of the handle of the instrument
according to various embodiments of the present invention;
[0058] FIGS. 71 and 72 are partial perspective views of the handle
according to various embodiments of the present invention;
[0059] FIG. 73 is a side view of the handle according to various
embodiments of the present invention;
[0060] FIGS. 74-75 illustrate a proportional sensor that may be
used according to various embodiments of the present invention;
[0061] FIGS. 76-90 illustrate mechanical blocking mechanisms and
the sequential operation of each according to various embodiments
of the present invention;
[0062] FIGS. 91-92 illustrate schematic diagrams of circuits used
in the instrument according to various embodiments of the present
invention;
[0063] FIG. 93 is a flow diagram of a process implemented by the
microcontroller of FIG. 92 according to various embodiments of the
present invention; and
[0064] FIG. 94 is a flow diagram of a process implemented by an
interlock according to various embodiments of the present
invention.
DETAILED DESCRIPTION
[0065] Various embodiments of the present invention are directed
generally to a surgical instrument having at least one remote
sensor transponder and means for communicating power and/or data
signals to the transponder(s) from a control unit. The present
invention may be used with any type of surgical instrument
comprising at least one sensor transponder, such as endoscopic or
laparoscopic surgical instruments, but is particularly useful for
surgical instruments where some feature of the instrument, such as
a free rotating joint, prevents or otherwise inhibits the use of a
wired connection to the sensor(s). Before describing aspects of the
system, one type of surgical instrument in which embodiments of the
present invention may be used--an endoscopic stapling and cutting
instrument (i.e., an endocutter)--is first described by way of
illustration.
[0066] FIGS. 1 and 2 depict an endoscopic surgical instrument 10
that comprises a handle 6, a shaft 8, and an articulating end
effector 12 pivotally connected to the shaft 8 at an articulation
pivot 14. Correct placement and orientation of the end effector 12
may be facilitated by controls on the hand 6, including (1) a
rotation knob 28 for rotating the closure tube (described in more
detail below in connection with FIGS. 4-5) at a free rotating joint
29 of the shaft 8 to thereby rotate the end effector 12 and (2) an
articulation control 16 to effect rotational articulation of the
end effector 12 about the articulation pivot 14. In the illustrated
embodiment, the end effector 12 is configured to act as an
endocutter for clamping, severing and stapling tissue, although in
other embodiments, different types of end effectors may be used,
such as end effectors for other types of surgical instruments, such
as graspers, cutters, staplers, clip appliers, access devices,
drug/gene therapy devices, ultrasound, RF or laser devices,
etc.
[0067] The handle 6 of the instrument 10 may include a closure
trigger 18 and a firing trigger 20 for actuating the end effector
12. It will be appreciated that instruments having end effectors
directed to different surgical tasks may have different numbers or
types of triggers or other suitable controls for operating the end
effector 12. The end effector 12 is shown separated from the handle
6 by the preferably elongate shaft 8. In one embodiment, a
clinician or operator of the instrument 10 may articulate the end
effector 12 relative to the shaft 8 by utilizing the articulation
control 16, as described in more detail in U.S. patent application
Ser. No. 11/329,020, filed Jan. 10, 2006, entitled SURGICAL
INSTRUMENT HAVING AN ARTICULATING END EFFECTOR, now U.S. Pat. No.
7,670,334, which is incorporated herein by reference.
[0068] The end effector 12 includes in this example, among other
things, a staple channel 22 and a pivotally translatable clamping
member, such as an anvil 24, which are maintained at a spacing that
assures effective stapling and severing of tissue clamped in the
end effector 12. The handle 6 includes a pistol grip 26 towards
which a closure trigger 18 is pivotally drawn by the clinician to
cause clamping or closing of the anvil 24 toward the staple channel
22 of the end effector 12 to thereby clamp tissue positioned
between the anvil 24 and channel 22. The firing trigger 20 is
farther outboard of the closure trigger 18. Once the closure
trigger 18 is locked in the closure position, the firing trigger 20
may rotate slightly toward the pistol grip 26 so that it can be
reached by the operator using one hand. Then the operator may
pivotally draw the firing trigger 20 toward the pistol grip 12 to
cause the stapling and severing of clamped tissue in the end
effector 12. U.S. patent application Ser. No. 11/343,573, filed
Jan. 31, 2006, entitled MOTOR-DRIVEN SURGICAL CUTTING AND FASTENING
INSTRUMENT WITH LOADING FORCE FEEDBACK, now U.S. Pat. No.
7,416,101, (the '573 application) which is incorporated herein by
reference, describes various configurations for locking and
unlocking the closure trigger 18. In other embodiments, different
types of clamping members besides the anvil 24 could be used, such
as, for example, an opposing jaw, etc.
[0069] It will be appreciated that the terms "proximal" and
"distal" are used herein with reference to a clinician gripping the
handle 6 of an instrument 10. Thus, the end effector 12 is distal
with respect to the more proximal handle 6. It will be further
appreciated that, for convenience and clarity, spatial terms such
as "vertical" and "horizontal" are used herein with respect to the
drawings. However, surgical instruments are used in many
orientations and positions, and these terms are not intended to be
limiting and absolute.
[0070] The closure trigger 18 may be actuated first. Once the
clinician is satisfied with the positioning of the end effector 12,
the clinician may draw back the closure trigger 18 to its fully
closed, locked position proximate to the pistol grip 26. The firing
trigger 20 may then be actuated. The firing trigger 20 returns to
the open position (shown in FIGS. 1 and 2) when the clinician
removes pressure. A release button 30 on the handle 6, and in this
example, on the pistol grip 26 of the handle, when depressed may
release the locked closure trigger 18.
[0071] FIG. 3 is an exploded view of the end effector 12 according
to various embodiments. As shown in the illustrated embodiment, the
end effector 12 may include, in addition to the
previously-mentioned channel 22 and anvil 24, a cutting instrument
32, a sled 33, a staple cartridge 34 that is removably seated in
the channel 22, and a helical screw shaft 36. The cutting
instrument 32 may be, for example, a knife. The anvil 24 may be
pivotably opened and closed at a pivot point 25 connected to the
proximate end of the channel 22. The anvil 24 may also include a
tab 27 at its proximate end that is inserted into a component of
the mechanical closure system (described further below) to open and
close the anvil 24. When the closure trigger 18 is actuated, that
is, drawn in by a user of the instrument 10, the anvil 24 may pivot
about the pivot point 25 into the clamped or closed position. If
clamping of the end effector 12 is satisfactory, the operator may
actuate the firing trigger 20, which, as explained in more detail
below, causes the knife 32 and sled 33 to travel longitudinally
along the channel 22, thereby cutting tissue clamped within the end
effector 12. The movement of the sled 33 along the channel 22
causes the staples of the staple cartridge 34 to be driven through
the severed tissue and against the closed anvil 24, which turns the
staples to fasten the severed tissue. U.S. Pat. No. 6,978,921,
entitled SURGICAL STAPLING INSTRUMENT INCORPORATING AN E-BEAM
FIRING MECHANISM, which is incorporated herein by reference,
provides more details about such two-stroke cutting and fastening
instruments. The sled 33 may be part of the cartridge 34, such that
when the knife 32 retracts following the cutting operation, the
sled 33 does not retract. The channel 22 and the anvil 24 may be
made of an electrically conductive material (such as metal) so that
they may serve as part of the antenna that communicates with the
sensor(s) in the end effector, as described further below. The
cartridge 34 could be made of a nonconductive material (such as
plastic) and the sensor may be connected to or disposed in the
cartridge 34, as described further below.
[0072] It should be noted that although the embodiments of the
instrument 10 described herein employ an end effector 12 that
staples the severed tissue, in other embodiments different
techniques for fastening or sealing the severed tissue may be used.
For example, end effectors that use RF energy or adhesives to
fasten the severed tissue may also be used. U.S. Pat. No.
5,709,680, entitled ELECTROSURGICAL HEMOSTATIC DEVICE, and U.S.
Pat. No. 5,688,270, entitled ELECTROSURGICAL HEMOSTATIC DEVICE WITH
RECESSED AND/OR OFFSET ELECTRODES, which are incorporated herein by
reference, discloses cutting instruments that use RF energy to
fasten the severed tissue. U.S. patent application Ser. No.
11/267,811, now U.S. Pat. No. 7,673,783 and U.S. patent application
Ser. No. 11/267,383, now U.S. Pat. No. 7,607,557, which are also
incorporated herein by reference, disclose cutting instruments that
use adhesives to fasten the severed tissue. Accordingly, although
the description herein refers to cutting/stapling operations and
the like, it should be recognized that this is an exemplary
embodiment and is not meant to be limiting. Other tissue-fastening
techniques may also be used.
[0073] FIGS. 4 and 5 are exploded views and FIG. 6 is a side view
of the end effector 12 and shaft 8 according to various
embodiments. As shown in the illustrated embodiment, the shaft 8
may include a proximate closure tube 40 and a distal closure tube
42 pivotably linked by a pivot links 44. The distal closure tube 42
includes an opening 45 into which the tab 27 on the anvil 24 is
inserted in order to open and close the anvil 24. Disposed inside
the closure tubes 40, 42 may be a proximate spine tube 46. Disposed
inside the proximate spine tube 46 may be a main rotational (or
proximate) drive shaft 48 that communicates with a secondary (or
distal) drive shaft 50 via a bevel gear assembly 52. The secondary
drive shaft 50 is connected to a drive gear 54 that engages a
proximate drive gear 56 of the helical screw shaft 36. The vertical
bevel gear 52b may sit and pivot in an opening 57 in the distal end
of the proximate spine tube 46. A distal spine tube 58 may be used
to enclose the secondary drive shaft 50 and the drive gears 54, 56.
Collectively, the main drive shaft 48, the secondary drive shaft
50, and the articulation assembly (e.g., the bevel gear assembly
52a-c), are sometimes referred to herein as the "main drive shaft
assembly." The closure tubes 40, 42 may be made of electrically
conductive material (such as metal) so that they may serve as part
of the antenna, as described further below. Components of the main
drive shaft assembly (e.g., the drive shafts 48, 50) may be made of
a nonconductive material (such as plastic).
[0074] A bearing 38, positioned at a distal end of the staple
channel 22, receives the helical drive screw 36, allowing the
helical drive screw 36 to freely rotate with respect to the channel
22. The helical screw shaft 36 may interface a threaded opening
(not shown) of the knife 32 such that rotation of the shaft 36
causes the knife 32 to translate distally or proximately (depending
on the direction of the rotation) through the staple channel 22.
Accordingly, when the main drive shaft 48 is caused to rotate by
actuation of the firing trigger 20 (as explained in more detail
below), the bevel gear assembly 52a-c causes the secondary drive
shaft 50 to rotate, which in turn, because of the engagement of the
drive gears 54, 56, causes the helical screw shaft 36 to rotate,
which causes the knife 32 to travel longitudinally along the
channel 22 to cut any tissue clamped within the end effector. The
sled 33 may be made of, for example, plastic, and may have a sloped
distal surface. As the sled 33 traverses the channel 22, the sloped
forward surface may push up or drive the staples in the staple
cartridge 34 through the clamped tissue and against the anvil 24.
The anvil 24 turns the staples, thereby stapling the severed
tissue. When the knife 32 is retracted, the knife 32 and sled 33
may become disengaged, thereby leaving the sled 33 at the distal
end of the channel 22.
[0075] According to various embodiments, as shown FIGS. 7-10, the
surgical instrument may include a battery 64 in the handle 6. The
illustrated embodiment provides user-feedback regarding the
deployment and loading force of the cutting instrument in the end
effector 12. In addition, the embodiment may use power provided by
the user in retracting the firing trigger 18 to power the
instrument 10 (a so-called "power assist" mode). As shown in the
illustrated embodiment, the handle 6 includes exterior lower side
pieces 59, 60 and exterior upper side pieces 61, 62 that fit
together to form, in general, the exterior of the handle 6. The
handle pieces 59-62 may be made of an electrically nonconductive
material, such as plastic. A battery 64 may be provided in the
pistol grip portion 26 of the handle 6. The battery 64 powers a
motor 65 disposed in an upper portion of the pistol grip portion 26
of the handle 6. The battery 64 may be constructed according to any
suitable construction or chemistry including, for example, a Li-ion
chemistry such as LiCoO.sub.2 or LiNiO.sub.2, a Nickel Metal
Hydride chemistry, etc. According to various embodiments, the motor
65 may be a DC brushed driving motor having a maximum rotation of,
approximately, 5000 RPM to 100,000 RPM. The motor 64 may drive a
90.degree. bevel gear assembly 66 comprising a first bevel gear 68
and a second bevel gear 70. The bevel gear assembly 66 may drive a
planetary gear assembly 72. The planetary gear assembly 72 may
include a pinion gear 74 connected to a drive shaft 76. The pinion
gear 74 may drive a mating ring gear 78 that drives a helical gear
drum 80 via a drive shaft 82. A ring 84 may be threaded on the
helical gear drum 80. Thus, when the motor 65 rotates, the ring 84
is caused to travel along the helical gear drum 80 by means of the
interposed bevel gear assembly 66, planetary gear assembly 72 and
ring gear 78.
[0076] The handle 6 may also include a run motor sensor 110 in
communication with the firing trigger 20 to detect when the firing
trigger 20 has been drawn in (or "closed") toward the pistol grip
portion 26 of the handle 6 by the operator to thereby actuate the
cutting/stapling operation by the end effector 12. The sensor 110
may be a proportional sensor such as, for example, a rheostat or
variable resistor. When the firing trigger 20 is drawn in, the
sensor 110 detects the movement, and sends an electrical signal
indicative of the voltage (or power) to be supplied to the motor
65. When the sensor 110 is a variable resistor or the like, the
rotation of the motor 65 may be generally proportional to the
amount of movement of the firing trigger 20. That is, if the
operator only draws or closes the firing trigger 20 in a little
bit, the rotation of the motor 65 is relatively low. When the
firing trigger 20 is fully drawn in (or in the fully closed
position), the rotation of the motor 65 is at its maximum. In other
words, the harder the user pulls on the firing trigger 20, the more
voltage is applied to the motor 65, causing greater rates of
rotation. In another embodiment, for example, the control unit
(described further below) may output a PWM control signal to the
motor 65 based on the input from the sensor 110 in order to control
the motor 65.
[0077] The handle 6 may include a middle handle piece 104 adjacent
to the upper portion of the firing trigger 20. The handle 6 also
may comprise a bias spring 112 connected between posts on the
middle handle piece 104 and the firing trigger 20. The bias spring
112 may bias the firing trigger 20 to its fully open position. In
that way, when the operator releases the firing trigger 20, the
bias spring 112 will pull the firing trigger 20 to its open
position, thereby removing actuation of the sensor 110, thereby
stopping rotation of the motor 65. Moreover, by virtue of the bias
spring 112, any time a user closes the firing trigger 20, the user
will experience resistance to the closing operation, thereby
providing the user with feedback as to the amount of rotation
exerted by the motor 65. Further, the operator could stop
retracting the firing trigger 20 to thereby remove force from the
sensor 100, to thereby stop the motor 65. As such, the user may
stop the deployment of the end effector 12, thereby providing a
measure of control of the cutting/fastening operation to the
operator.
[0078] The distal end of the helical gear drum 80 includes a distal
drive shaft 120 that drives a ring gear 122, which mates with a
pinion gear 124. The pinion gear 124 is connected to the main drive
shaft 48 of the main drive shaft assembly. In that way, rotation of
the motor 65 causes the main drive shaft assembly to rotate, which
causes actuation of the end effector 12, as described above.
[0079] The ring 84 threaded on the helical gear drum 80 may include
a post 86 that is disposed within a slot 88 of a slotted arm 90.
The slotted arm 90 has an opening 92 at its opposite end 94 that
receives a pivot pin 96 that is connected between the handle
exterior side pieces 59, 60. The pivot pin 96 is also disposed
through an opening 100 in the firing trigger 20 and an opening 102
in the middle handle piece 104.
[0080] In addition, the handle 6 may include a reverse motor (or
end-of-stroke sensor) 130 and a stop motor (or beginning-of-stroke)
sensor 142. In various embodiments, the reverse motor sensor 130
may be a limit switch located at the distal end of the helical gear
drum 80 such that the ring 84 threaded on the helical gear drum 80
contacts and trips the reverse motor sensor 130 when the ring 84
reaches the distal end of the helical gear drum 80. The reverse
motor sensor 130, when activated, sends a signal to the control
unit which sends a signal to the motor 65 to reverse its rotation
direction, thereby withdrawing the knife 32 of the end effector 12
following the cutting operation.
[0081] The stop motor sensor 142 may be, for example, a
normally-closed limit switch. In various embodiments, it may be
located at the proximate end of the helical gear drum 80 so that
the ring 84 trips the switch 142 when the ring 84 reaches the
proximate end of the helical gear drum 80.
[0082] In operation, when an operator of the instrument 10 pulls
back the firing trigger 20, the sensor 110 detects the deployment
of the firing trigger 20 and sends a signal to the control unit
which sends a signal to the motor 65 to cause forward rotation of
the motor 65 at, for example, a rate proportional to how hard the
operator pulls back the firing trigger 20. The forward rotation of
the motor 65 in turn causes the ring gear 78 at the distal end of
the planetary gear assembly 72 to rotate, thereby causing the
helical gear drum 80 to rotate, causing the ring 84 threaded on the
helical gear drum 80 to travel distally along the helical gear drum
80. The rotation of the helical gear drum 80 also drives the main
drive shaft assembly as described above, which in turn causes
deployment of the knife 32 in the end effector 12. That is, the
knife 32 and sled 33 are caused to traverse the channel 22
longitudinally, thereby cutting tissue clamped in the end effector
12. Also, the stapling operation of the end effector 12 is caused
to happen in embodiments where a stapling-type end effector is
used.
[0083] By the time the cutting/stapling operation of the end
effector 12 is complete, the ring 84 on the helical gear drum 80
will have reached the distal end of the helical gear drum 80,
thereby causing the reverse motor sensor 130 to be tripped, which
sends a signal to the control unit which sends a signal to the
motor 65 to cause the motor 65 to reverse its rotation. This in
turn causes the knife 32 to retract, and also causes the ring 84 on
the helical gear drum 80 to move back to the proximate end of the
helical gear drum 80.
[0084] The middle handle piece 104 includes a backside shoulder 106
that engages the slotted arm 90 as best shown in FIGS. 8 and 9. The
middle handle piece 104 also has a forward motion stop 107 that
engages the firing trigger 20. The movement of the slotted arm 90
is controlled, as explained above, by rotation of the motor 65.
When the slotted arm 90 rotates CCW as the ring 84 travels from the
proximate end of the helical gear drum 80 to the distal end, the
middle handle piece 104 will be free to rotate CCW. Thus, as the
user draws in the firing trigger 20, the firing trigger 20 will
engage the forward motion stop 107 of the middle handle piece 104,
causing the middle handle piece 104 to rotate CCW. Due to the
backside shoulder 106 engaging the slotted arm 90, however, the
middle handle piece 104 will only be able to rotate CCW as far as
the slotted arm 90 permits. In that way, if the motor 65 should
stop rotating for some reason, the slotted arm 90 will stop
rotating, and the user will not be able to further draw in the
firing trigger 20 because the middle handle piece 104 will not be
free to rotate CCW due to the slotted arm 90.
[0085] Components of an exemplary closure system for closing (or
clamping) the anvil 24 of the end effector 12 by retracting the
closure trigger 18 are also shown in FIGS. 7-10. In the illustrated
embodiment, the closure system includes a yoke 250 connected to the
closure trigger 18 by a pin 251 that is inserted through aligned
openings in both the closure trigger 18 and the yoke 250. A pivot
pin 252, about which the closure trigger 18 pivots, is inserted
through another opening in the closure trigger 18 which is offset
from where the pin 251 is inserted through the closure trigger 18.
Thus, retraction of the closure trigger 18 causes the upper part of
the closure trigger 18, to which the yoke 250 is attached via the
pin 251, to rotate CCW. The distal end of the yoke 250 is
connected, via a pin 254, to a first closure bracket 256. The first
closure bracket 256 connects to a second closure bracket 258.
Collectively, the closure brackets 256, 258 define an opening in
which the proximate end of the proximate closure tube 40 (see FIG.
4) is seated and held such that longitudinal movement of the
closure brackets 256, 258 causes longitudinal motion by the
proximate closure tube 40. The instrument 10 also includes a
closure rod 260 disposed inside the proximate closure tube 40. The
closure rod 260 may include a window 261 into which a post 263 on
one of the handle exterior pieces, such as exterior lower side
piece 59 in the illustrated embodiment, is disposed to fixedly
connect the closure rod 260 to the handle 6. In that way, the
proximate closure tube 40 is capable of moving longitudinally
relative to the closure rod 260. The closure rod 260 may also
include a distal collar 267 that fits into a cavity 269 in
proximate spine tube 46 and is retained therein by a cap 271 (see
FIG. 4).
[0086] In operation, when the yoke 250 rotates due to retraction of
the closure trigger 18, the closure brackets 256, 258 cause the
proximate closure tube 40 to move distally (i.e., away from the
handle end of the instrument 10), which causes the distal closure
tube 42 to move distally, which causes the anvil 24 to rotate about
the pivot point 25 into the clamped or closed position. When the
closure trigger 18 is unlocked from the locked position, the
proximate closure tube 40 is caused to slide proximately, which
causes the distal closure tube 42 to slide proximately, which, by
virtue of the tab 27 being inserted in the window 45 of the distal
closure tube 42, causes the anvil 24 to pivot about the pivot point
25 into the open or unclamped position. In that way, by retracting
and locking the closure trigger 18, an operator may clamp tissue
between the anvil 24 and channel 22, and may unclamp the tissue
following the cutting/stapling operation by unlocking the closure
trigger 18 from the locked position.
[0087] The control unit (described further below) may receive the
outputs from end-of-stroke and beginning-of-stroke sensors 130, 142
and the run-motor sensor 110, and may control the motor 65 based on
the inputs. For example, when an operator initially pulls the
firing trigger 20 after locking the closure trigger 18, the
run-motor sensor 110 is actuated. If the staple cartridge 34 is
present in the end effector 12, a cartridge lockout sensor (not
shown) may be closed, in which case the control unit may output a
control signal to the motor 65 to cause the motor 65 to rotate in
the forward direction. When the end effector 12 reaches the end of
its stroke, the reverse motor sensor 130 will be activated. The
control unit may receive this output from the reverse motor sensor
130 and cause the motor 65 to reverse its rotational direction.
When the knife 32 is fully retracted, the stop motor sensor switch
142 is activated, causing the control unit to stop the motor
65.
[0088] In other embodiments, rather than a proportional-type sensor
110, an on-off type sensor could be used. In such embodiments, the
rate of rotation of the motor 65 would not be proportional to the
force applied by the operator. Rather, the motor 65 would generally
rotate at a constant rate. But the operator would still experience
force feedback because the firing trigger 20 is geared into the
gear drive train.
[0089] The instrument 10 may include a number of sensor
transponders in the end effector 12 for sensing various conditions
related to the end effector 12, such as sensor transponders for
determining the status of the staple cartridge 34 (or other type of
cartridge depending on the type of surgical instrument), the
progress of the stapler during closure and firing, etc. The sensor
transponders may be passively powered by inductive signals, as
described further below, although in other embodiments the
transponders could be powered by a remote power source, such as a
battery in the end effector 12, for example. The sensor
transponder(s) could include magnetoresistive, optical,
electromechanical, RFID, MEMS, motion or pressure sensors, for
example. These sensor transponders may be in communication with a
control unit 300, which may be housed in the handle 6 of the
instrument 10, for example, as shown in FIG. 11.
[0090] As shown in FIG. 12, according to various embodiments the
control unit 300 may comprise a processor 306 and one or more
memory units 308. By executing instruction code stored in the
memory 308, the processor 306 may control various components of the
instrument 10, such as the motor 65 or a user display (not shown),
based on inputs received from the various end effector sensor
transponders and other sensor(s) (such as the run-motor sensor 110,
the end-of-stroke sensor 130, and the beginning-of-stroke sensor
142, for example). The control unit 300 may be powered by the
battery 64 during surgical use of instrument 10. The control unit
300 may comprise an inductive element 302 (e.g., a coil or antenna)
to pick up wireless signals from the sensor transponders, as
described in more detail below. Input signals received by the
inductive element 302 acting as a receiving antenna may be
demodulated by a demodulator 310 and decoded by a decoder 312. The
input signals may comprise data from the sensor transponders in the
end effector 12, which the processor 306 may use to control various
aspects of the instrument 10.
[0091] To transmit signals to the sensor transponders, the control
unit 300 may comprise an encoder 316 for encoding the signals and a
modulator 318 for modulating the signals according to the
modulation scheme. The inductive element 302 may act as the
transmitting antenna. The control unit 300 may communicate with the
sensor transponders using any suitable wireless communication
protocol and any suitable frequency (e.g., an ISM band). Also, the
control unit 300 may transmit signals at a different frequency
range than the frequency range of the received signals from the
sensor transponders. Also, although only one antenna (inductive
element 302) is shown in FIG. 12, in other embodiments the control
unit 300 may have separate receiving and transmitting antennas.
[0092] According to various embodiments, the control unit 300 may
comprise a microcontroller, a microprocessor, a field programmable
gate array (FPGA), one or more other types of integrated circuits
(e.g., RF receivers and PWM controllers), and/or discrete passive
components. The control units may also be embodied as
system-on-chip (SoC) or a system-in-package (SIP), for example.
[0093] As shown in FIG. 11, the control unit 300 may be housed in
the handle 6 of the instrument 10 and one or more of the sensor
transponders 368 for the instrument 10 may be located in the end
effector 12. To deliver power and/or transmit data to or from the
sensor transponders 368 in the end effector 12, the inductive
element 302 of the control unit 300 may be inductively coupled to a
secondary inductive element (e.g., a coil) 320 positioned in the
shaft 8 distally from the rotation joint 29. The secondary
inductive element 320 is preferably electrically insulated from the
conductive shaft 8.
[0094] The secondary inductive element 320 may be connected by an
electrically conductive, insulated wire 322 to a distal inductive
element (e.g., a coil) 324 located near the end effector 12, and
preferably distally relative to the articulation pivot 14. The wire
322 may be made of an electrically conductive polymer and/or metal
(e.g., copper) and may be sufficiently flexible so that it could
pass though the articulation pivot 14 and not be damaged by
articulation. The distal inductive element 324 may be inductively
coupled to the sensor transponder 368 in, for example, the
cartridge 34 of the end effector 12. The transponder 368, as
described in more detail below, may include an antenna (or coil)
for inductive coupling to the distal coil 324, a sensor and
integrated control electronics for receiving and transmitting
wireless communication signals.
[0095] The transponder 368 may use a portion of the power of the
inductive signal received from the distal inductive element 326 to
passively power the transponder 368. Once sufficiently powered by
the inductive signals, the transponder 368 may receive and transmit
data to the control unit 300 in the handle 6 via (i) the inductive
coupling between the transponder 368 and the distal inductive
element 324, (ii) the wire 322, and (iii) the inductive coupling
between the secondary inductive element 320 and the control unit
300. That way, the control unit 300 may communicate with the
transponder 368 in the end effector 12 without a direct wired
connection through complex mechanical joints like the rotating
joint 29 and/or without a direct wired connection from the shaft 8
to the end effector 12, places where it may be difficult to
maintain such a wired connection. In addition, because the
distances between the inductive elements (e.g., the spacing between
(i) the transponder 368 and the distal inductive element 324, and
(ii) the secondary inductive element 320 and the control unit 300)
and fixed and known, the couplings could be optimized for inductive
transfer of energy. Also, the distances could be relatively short
so that relatively low power signals could be used to thereby
minimize interference with other systems in the use environment of
the instrument 10.
[0096] In the embodiment of FIG. 12, the inductive element 302 of
the control unit 300 is located relatively near to the control unit
300. According to other embodiments, as shown in FIG. 13, the
inductive element 302 of the control unit 300 may be positioned
closer to the rotating joint 29 to that it is closer to the
secondary inductive element 320, thereby reducing the distance of
the inductive coupling in such an embodiment. Alternatively, the
control unit 300 (and hence the inductive element 302) could be
positioned closer to the secondary inductive element 320 to reduce
the spacing.
[0097] In other embodiments, more or fewer than two inductive
couplings may be used. For example, in some embodiments, the
surgical instrument 10 may use a single inductive coupling between
the control unit 300 in the handle 6 and the transponder 368 in the
end effector 12, thereby eliminating the inductive elements 320,
324 and the wire 322. Of course, in such an embodiment, a stronger
signal may be required due to the greater distance between the
control unit 300 in the handle 6 and the transponder 368 in the end
effector 12. Also, more than two inductive couplings could be used.
For example, if the surgical instrument 10 had numerous complex
mechanical joints where it would be difficult to maintain a direct
wired connection, inductive couplings could be used to span each
such joint. For example, inductive couplers could be used on both
sides of the rotary joint 29 and both sides of the articulation
pivot 14, with the inductive element 321 on the distal side of the
rotary joint 29 connected by a wire 322 to the inductive element
324 of the proximate side of the articulation pivot, and a wire 323
connecting the inductive elements 325, 326 on the distal side of
the articulation pivot 14 as shown in FIG. 14. In this embodiment,
the inductive element 326 may communicate with the sensor
transponder 368.
[0098] In addition, the transponder 368 may include a number of
different sensors. For example, it may include an array of sensors.
Further, the end effector 12 could include a number of sensor
transponders 368 in communication with the distal inductive element
324 (and hence the control unit 300). Also, the inductive elements
320, 324 may or may not include ferrite cores. As mentioned before,
they are also preferably insulated from the electrically conductive
outer shaft (or frame) of the instrument 10 (e.g., the closure
tubes 40, 42), and the wire 322 is also preferably insulated from
the outer shaft 8.
[0099] FIG. 15 is a diagram of an end effector 12 including a
transponder 368 held or embedded in the cartridge 34 at the distal
end of the channel 22. The transponder 368 may be connected to the
cartridge 34 by a suitable bonding material, such as epoxy. In this
embodiment, the transponder 368 includes a magnetoresistive sensor.
The anvil 24 also includes a permanent magnet 369 at its distal end
and generally facing the transponder 368. The end effector 12 also
includes a permanent magnet 370 connected to the sled 33 in this
example embodiment. This allows the transponder 368 to detect both
opening/closing of the end effector 12 (due to the permanent magnet
369 moving further or closer to the transponder as the anvil 24
opens and closes) and completion of the stapling/cutting operation
(due to the permanent magnet 370 moving toward the transponder 368
as the sled 33 traverses the channel 22 as part of the cutting
operation).
[0100] FIG. 15 also shows the staples 380 and the staple drivers
382 of the staple cartridge 34. As explained previously, according
to various embodiments, when the sled 33 traverses the channel 22,
the sled 33 drives the staple drivers 382 which drive the staples
380 into the severed tissue held in the end effector 12, the
staples 380 being formed against the anvil 24. As noted above, such
a surgical cutting and fastening instrument is but one type of
surgical instrument in which the present invention may be
advantageously employed. Various embodiments of the present
invention may be used in any type of surgical instrument having one
or more sensor transponders.
[0101] In the embodiments described above, the battery 64 powers
(at least partially) the firing operation of the instrument 10. As
such, the instrument may be a so-called "power-assist" device. More
details and additional embodiments of power-assist devices are
described in the '573 application, which is incorporated herein. It
should be recognized, however, that the instrument 10 need not be a
power-assist device and that this is merely an example of a type of
device that may utilize aspects of the present invention. For
example, the instrument 10 may include a user display (such as a
LCD or LED display) that is powered by the battery 64 and
controlled by the control unit 300. Data from the sensor
transponders 368 in the end effector 12 may be displayed on such a
display.
[0102] In another embodiment, the shaft 8 of the instrument 10,
including for example, the proximate closure tube 40 and the distal
closure tube 42, may collectively serve as part of an antenna for
the control unit 300 by radiating signals to the sensor transponder
368 and receiving radiated signals from the sensor transponder 368.
That way, signals to and from the remote sensor in the end effector
12 may be transmitted via the shaft 8 of the instrument 10.
[0103] The proximate closure tube 40 may be grounded at its
proximate end by the exterior lower and upper side pieces 59-62,
which may be made of a nonelectrically conductive material, such as
plastic. The drive shaft assembly components (including the main
drive shaft 48 and secondary drive shaft 50) inside the proximate
and distal closure tubes 40, 42 may also be made of a
nonelectrically conductive material, such as plastic. Further,
components of end effector 12 (such as the anvil 24 and the channel
22) may be electrically coupled to (or in direct or indirect
electrical contact with) the distal closure tube 42 such that they
may also serve as part of the antenna. Further, the sensor
transponder 368 could be positioned such that it is electrically
insulated from the components of the shaft 8 and end effector 12
serving as the antenna. For example, the sensor transponder 368 may
be positioned in the cartridge 34, which may be made of a
nonelectrically conductive material, such as plastic. Because the
distal end of the shaft 8 (such as the distal end of the distal
closure tube 42) and the portions of the end effector 12 serving as
the antenna may be relatively close in distance to the sensor 368,
the power for the transmitted signals may be held at low levels,
thereby minimizing or reducing interference with other systems in
the use environment of the instrument 10.
[0104] In such an embodiment, as shown in FIG. 16, the control unit
300 may be electrically coupled to the shaft 8 of the instrument
10, such as to the proximate closure tube 40, by a conductive link
400 (e.g., a wire). Portions of the outer shaft 8, such as the
closure tubes 40, 42, may therefore act as part of an antenna for
the control unit 300 by radiating signals to the sensor 368 and
receiving radiated signals from the sensor 368. Input signals
received by the control unit 300 may be demodulated by the
demodulator 310 and decoded by the decoder 312 (see FIG. 12). The
input signals may comprise data from the sensors 368 in the end
effector 12, which the processor 306 may use to control various
aspects of the instrument 10, such as the motor 65 or a user
display.
[0105] To transmit data signals to or from the sensors 368 in the
end effector 12, the link 400 may connect the control unit 300 to
components of the shaft 8 of the instrument 10, such as the
proximate closure tube 40, which may be electrically connected to
the distal closure tube 42. The distal closure tube 42 is
preferably electrically insulated from the remote sensor 368, which
may be positioned in the plastic cartridge 34 (see FIG. 3). As
mentioned before, components of the end effector 12, such as the
channel 22 and the anvil 24 (see FIG. 3), may be conductive and in
electrical contact with the distal closure tube 42 such that they,
too, may serve as part of the antenna.
[0106] With the shaft 8 acting as the antenna for the control unit
300, the control unit 300 can communicate with the sensor 368 in
the end effector 12 without a direct wired connection. In addition,
because the distances between shaft 8 and the remote sensor 368 is
fixed and known, the power levels could be optimized for low levels
to thereby minimize interference with other systems in the use
environment of the instrument 10. The sensor 368 may include
communication circuitry for radiating signals to the control unit
300 and for receiving signals from the control unit 300, as
described above. The communication circuitry may be integrated with
the sensor 368.
[0107] In another embodiment, the components of the shaft 8 and/or
the end effector 12 may serve as an antenna for the remote sensor
368. In such an embodiment, the remote sensor 368 is electrically
connected to the shaft (such as to distal closure tube 42, which
may be electrically connected to the proximate closure tube 40) and
the control unit 300 is insulated from the shaft 8. For example,
the sensor 368 could be connected to a conductive component of the
end effector 12 (such as the channel 22), which in turn may be
connected to conductive components of the shaft (e.g., the closure
tubes 40, 42). Alternatively, the end effector 12 may include a
wire (not shown) that connects the remote sensor 368 the distal
closure tube 42.
[0108] Typically, surgical instruments, such as the instrument 10,
are cleaned and sterilized prior to use. In one sterilization
technique, the instrument 10 is placed in a closed and sealed
container 280, such as a plastic or TYVEK container or bag, as
shown in FIGS. 17 and 18. The container and the instrument are then
placed in a field of radiation that can penetrate the container,
such as gamma radiation, x-rays, or high-energy electrons. The
radiation kills bacteria on the instrument 10 and in the container
280. The sterilized instrument 10 can then be stored in the sterile
container 280. The sealed, sterile container 280 keeps the
instrument 10 sterile until it is opened in a medical facility or
some other use environment. Instead of radiation, other means of
sterilizing the instrument 10 may be used, such as ethylene oxide
or steam.
[0109] When radiation, such as gamma radiation, is used to
sterilize the instrument 10, components of the control unit 300,
particularly the memory 308 and the processor 306, may be damaged
and become unstable. Thus, according to various embodiments of the
present invention, the control unit 300 may be programmed after
packaging and sterilization of the instrument 10.
[0110] As shown in FIG. 17, a remote programming device 320, which
may be a handheld device, may be brought into wireless
communication with the control unit 300. The remote programming
device 320 may emit wireless signals that are received by the
control unit 300 to program the control unit 300 and to power the
control unit 300 during the programming operation. That way, the
battery 64 does not need to power the control unit 300 during the
programming operation. According to various embodiments, the
programming code downloaded to the control unit 300 could be of
relatively small size, such as 1 MB or less, so that a
communications protocol with a relatively low data transmission
rate could be used if desired. Also, the remote programming unit
320 could be brought into close physical proximity with the
surgical instrument 10 so that a low power signal could be
used.
[0111] Referring back to FIG. 19, the control unit 300 may comprise
an inductive coil 402 to pick up wireless signals from a remote
programming device 320. A portion of the received signal may be
used by a power circuit 404 to power the control unit 300 when it
is not being powered by the battery 64.
[0112] Input signals received by the coil 402 acting as a receiving
antenna may be demodulated by a demodulator 410 and decoded by a
decoder 412. The input signals may comprise programming
instructions (e.g., code), which may be stored in a non-volatile
memory portion of the memory 308. The processor 306 may execute the
code when the instrument 10 is in operation. For example, the code
may cause the processor 306 to output control signals to various
sub-systems of the instrument 10, such as the motor 65, based on
data received from the sensors 368.
[0113] The control unit 300 may also comprise a non-volatile memory
unit 414 that comprises boot sequence code for execution by the
processor 306. When the control unit 300 receives enough power from
the signals from the remote control unit 320 during the
post-sterilization programming operation, the processor 306 may
first execute the boot sequence code ("boot loader") 414, which may
load the processor 306 with an operating system.
[0114] The control unit 300 may also send signals back to the
remote programming unit 320, such as acknowledgement and handshake
signals, for example. The control unit 300 may comprise an encoder
416 for encoding the signals to then be sent to the programming
device 320 and a modulator 418 for modulating the signals according
to the modulation scheme. The coil 402 may act as the transmitting
antenna. The control unit 300 and the remote programming device 320
may communicate using any suitable wireless communication protocol
(e.g., Bluetooth) and any suitable frequency (e.g., an ISM band).
Also, the control unit 300 may transmit signals at a different
frequency range than the frequency range of the received signals
from the remote programming unit 320.
[0115] FIG. 20 is a simplified diagram of the remote programming
device 320 according to various embodiments of the present
invention. As shown in FIG. 20, the remote programming unit 320 may
comprise a main control board 230 and a boosted antenna board 232.
The main control board 230 may comprise a controller 234, a power
module 236, and a memory 238. The memory 238 may stored the
operating instructions for the controller 234 as well as the
programming instructions to be transmitted to the control unit 300
of the surgical instrument 10. The power module 236 may provide a
stable DC voltage for the components of the remote programming
device 320 from an internal battery (not shown) or an external AC
or DC power source (not shown).
[0116] The boosted antenna board 232 may comprise a coupler circuit
240 that is in communication with the controller 234 via an
I.sup.2C bus, for example. The coupler circuit 240 may communicate
with the control unit 300 of the surgical instrument via an antenna
244. The coupler circuit 240 may handle the modulating/demodulating
and encoding/decoding operations for transmissions with the control
unit. According to other embodiments, the remote programming device
320 could have a discrete modulator, demodulator, encoder and
decoder. As shown in FIG. 20, the boost antenna board 232 may also
comprise a transmitting power amp 246, a matching circuit 248 for
the antenna 244, and a filter/amplifier 249 for receiving
signals.
[0117] According to other embodiments, as shown in FIG. 20, the
remote programming device could be in communication with a computer
device 460, such as a PC or a laptop, via a USB and/or RS232
interface, for example. In such a configuration, a memory of the
computing device 460 may store the programming instructions to be
transmitted to the control unit 300. In another embodiment, the
computing device 460 could be configured with a wireless
transmission system to transmit the programming instructions to the
control unit 300.
[0118] In addition, according to other embodiments, rather than
using inductive coupling between the control unit 300 and the
remote programming device 320, capacitively coupling could be used.
In such an embodiment, the control unit 300 could have a plate
instead of a coil, as could the remote programming unit 320.
[0119] In another embodiment, rather than using a wireless
communication link between the control unit 300 and the remote
programming device 320, the programming device 320 may be
physically connected to the control unit 300 while the instrument
10 is in its sterile container 280 in such a way that the
instrument 10 remains sterilized. FIG. 21 is a diagram of a
packaged instrument 10 according to such an embodiment. As shown in
FIG. 22, the handle 6 of the instrument 10 may include an external
connection interface 470. The container 280 may further comprise a
connection interface 472 that mates with the external connection
interface 470 of the instrument 10 when the instrument 10 is
packaged in the container 280. The programming device 320 may
include an external connection interface (not shown) that may
connect to the connection interface 472 at the exterior of the
container 280 to thereby provide a wired connection between the
programming device 320 and the external connection interface 470 of
the instrument 10.
[0120] In one embodiment, the present invention is directed to a
surgical instrument, such as an endoscopic or laparoscopic
instrument. The surgical instrument may comprise a shaft having a
distal end connected to an end effector and a handle connected to a
proximate end of the shaft. The handle may comprise a control unit
(e.g., a microcontroller) that is in communication with a first
sensor element. Further, the surgical instrument may comprise a
rotational joint for rotating the shaft. In such a case, the
surgical instrument may comprise the first element located in the
shaft distally from the rotational joint. The first element may be
coupled to the control unit either by a wired or wireless
electrical connection. A second element may be located in the end
effector and may be coupled to the first element by a wireless
electrical connection. The first and second elements may be
connected and/or coupled by a wired or a wireless electrical
connection.
[0121] The control unit may communicate with the second sensor
element in the end effector without a direct wired electrical
connection through complex mechanical joints like a rotating joint
or articulating pivot where it may be difficult to maintain such a
wired electrical connection. In addition, because the distances
between the inductive elements may be fixed and known, the
couplings between the first and second sensor elements may be
optimized for inductive and/or electromagnetic transfer of energy.
Also, the distances may be relatively short so that relatively low
power signals may be used to minimize interference with other
systems in the use environment of the instrument.
[0122] In another embodiment of the present invention, the
electrically conductive shaft of the surgical instrument may serve
as an antenna for the control unit to wirelessly communicate
signals to and from one or more sensor elements. For example, one
or more sensor elements may be located on or disposed in a
nonconductive component of the end effector, such as a plastic
cartridge, thereby insulating the sensor element from conductive
components of the end effector and the shaft. In addition, the
control unit in the handle may be electrically coupled to the
shaft. In that way, the shaft and/or the end effector may serve as
an antenna for the control unit to radiate signals from the control
unit to the one or more sensor elements and/or receive radiated
echo response signals from the one or more sensor elements. Such a
design is particularly useful in surgical instruments having
complex mechanical joints (such as rotary joints) and articulating
pivots, which make it difficult to use a direct wired electrical
connection between the sensor elements and the control unit for
communicating electrical signals therebetween.
[0123] Various embodiments of the present invention are directed
generally to a surgical instrument comprising one or more sensor
elements to sense the location, type, presence and/or status of
various components of interest disposed on the surgical instrument.
In one embodiment, the present invention is directed generally to a
surgical instrument having one or more sensor elements to sense the
location, type, presence and/or status of various components of
interest disposed in an end effector portion of the surgical
instrument. These components of interest may comprise, for example,
a sled, a staple cartridge, a cutting instrument or any other
component that may be disposed on the surgical instrument and more
particularly disposed in the end effector portion thereof. Although
the present invention may be used with any type of surgical
instrument such as endoscopic or laparoscopic surgical instruments,
it is particularly useful for surgical instruments comprising one
or more free rotating joints or an articulation pivots that make it
difficult to use wired electrical connections to the one or more
passive and/or active sensor elements.
[0124] The one or more sensor elements may be passive or active
sensor elements adapted to communicate with a control unit in any
suitable manner. In various embodiments, some of the sensor
elements may not be supplied power over a wired electrical
connection and as described herein, neither the passive nor the
active sensor elements may comprise an internal power supply. The
sensor elements may operate using the power provided by the minute
electrical current induced in the sensor element itself or an
antenna coupled to the sensor element by an incoming radio
frequency (RF) interrogation signal transmitted by the control
unit. This means that the antenna and/or the sensor element itself
may be designed to collect power from the incoming interrogation
signal and also to transmit an outbound backscatter signal in
response thereto. The lack of an onboard power supply means that
the sensor elements may have a relatively small form factor. In
embodiments comprising a passive sensor element RF interrogation
signals may be received by the passive sensor element wirelessly
over a predetermined channel. The incident electromagnetic
radiation associated with the RF interrogation signals is then
scattered or reflected back to the interrogating source such as the
control unit. Thus, the passive sensor element signals by
backscattering the carrier of the RF interrogation signal from the
control unit. In embodiments comprising an active sensor element,
on the other hand, just enough power may be received from the RF
interrogation signals to cause the active sensor element to power
up and transmit an analog or digital signal back to the control
unit in response in response to the RF interrogation signal. The
control unit may be referred to as a reader, interrogator or the
like.
[0125] In one embodiment, the status of a component (e.g., sled,
staple cartridge, cutting instrument) located in the end effector
portion of the surgical instrument may be determined through the
use of a system comprising passive and/or active sensor elements
coupled to a control unit. The passive sensor elements may be
formed of or comprise passive hardware elements such as resistive,
inductive and/or capacitive elements or any combination thereof.
The active sensor elements may be formed of or comprise active
hardware elements. These active hardware elements may be integrated
and/or discrete circuit elements or any combination thereof.
Examples of integrated and/or discrete hardware elements are
described herein below.
[0126] In one embodiment, the system may comprise a control unit
coupled to a primary sensor element (primary element) disposed at a
distal end of a shaft of the surgical instrument prior to an
articulation pivot (as described below) and a secondary sensor
element (secondary element) disposed on a component of interest in
an end effector portion of the surgical instrument located
subsequent to the articulation pivot (e.g., on a sled as described
below). Rather than transmitting continuous power to the secondary
element over a wired electrical connection, the primary element
wirelessly interrogates or illuminates the secondary element by
transmitting an electromagnetic pulse signal over a channel at a
predetermined frequency, duration and repetition rate. When the
interrogation pulse signal is incident upon, i.e., strikes or
illuminates, the secondary element, it generated an echo response
signal. The echo response signal is a reflection of the
electromagnetic energy incident upon the secondary element. After
transmitting the interrogation signal, the primary element listens
for the echo response signal reflected from the secondary element
and couples the echo response signal to the control unit in a
suitable form for subsequent processing. The echo response signal
may be of the same frequency as the interrogation pulse or some
harmonic frequency thereof. The amount of reflected energy in the
echo response signal depends upon the material, shape and size of
the secondary element. The amount of reflected energy in the echo
response signal also depends upon the distance between the primary
element and the secondary element. Therefore, the material, shape
and size of the secondary element as well as the relative distance
between the primary and secondary elements may be selected to
generate a unique echo response signal that is indicative of a
desired measurement associated with the component of interest
coupled to the secondary element. For example, unique echo response
signals may indicate the location, type, presence and/or status of
various components and sub-components disposed in the surgical
instrument. Especially, the various components and sub-components
disposed in the end effector portion of the surgical instrument
subsequent to a freely rotating joint or articulation pivot that
may make it difficult or impractical to provide a wired electrical
connection between the primary and the secondary elements. The echo
response signals also may be used to determine the distance between
the primary and secondary elements. In this manner, the secondary
element may be made integral with or may be attached to a component
of interest and the echo response signal may provide information
associated with the component of interest. This arrangement may
eliminate the need to transmit or provide power to the secondary
element over a wired connection and may be a cost effective
solution to providing various additional passive and/or active
sensor elements in the surgical instrument. Before describing
aspects of the system, one type of surgical instrument in which
embodiments of the present invention may be used--an endoscopic
stapling and cutting instrument (i.e., an endocutter)--is first
described by way of illustration.
[0127] FIGS. 23 and 24 depict an endoscopic surgical instrument
2010 that comprises a handle 2006, a shaft 2008, and an
articulating end effector 2012 pivotally connected to the shaft
2008 at an articulation pivot 2014. Correct placement and
orientation of the end effector 2012 may be facilitated by controls
on the hand 2006, including (1) a rotation knob 2028 for rotating
the closure tube (described in more detail below in connection with
FIGS. 26-27) at a free rotating joint 2029 of the shaft 2008 to
thereby rotate the end effector 2012 and (2) an articulation
control 2016 to effect rotational articulation of the end effector
2012 about the articulation pivot 2014. In the illustrated
embodiment, the end effector 2012 is configured to act as an
endocutter for clamping, severing and stapling tissue, although in
other embodiments, different types of end effectors may be used,
such as end effectors for other types of surgical instruments, such
as graspers, cutters, staplers, clip appliers, access devices,
drug/gene therapy devices, ultrasound, RF or laser devices,
etc.
[0128] The handle 2006 of the instrument 2010 may include a closure
trigger 2018 and a firing trigger 2020 for actuating the end
effector 2012. It will be appreciated that instruments having end
effectors directed to different surgical tasks may have different
numbers or types of triggers or other suitable controls for
operating the end effector 2012. The end effector 2012 is shown
separated from the handle 2006 by the preferably elongate shaft
2008. The handle may comprise a control unit 2300 (described below)
in communication with a first element 2021 by way of an electrical
connection 2023. The electrical connection 2023 may be a wired
electrical connection such as an electrically conductive insulated
wire or may be a wireless electrical connection. The electrically
conductive insulated wire may be made of an electrically conductive
polymer and/or metal (e.g., copper) and may be sufficiently
flexible so that it could pass through the articulation control
2016, the rotation knob 2028, the free rotating joint 2029 and
other components in the handle 2006 of the instrument 2010 without
being damaged by rotation. The first element 2021 may be disposed
at a distal end of the shaft 2008 prior to the articulation pivot
2014. A second element 2035 (shown in FIG. 25 below) may be
disposed in the articulating end effector 2012 and is in wireless
communication with the first element 2021. The operation of the
first and second elements 2021, 2023 and the control unit 2300 is
described below. In one embodiment, a clinician or operator of the
instrument 2010 may articulate the end effector 2012 relative to
the shaft 2008 by utilizing the articulation control 2016, as
described in more detail in U.S. patent application Ser. No.
11/329,020, filed Jan. 10, 2006, entitled SURGICAL INSTRUMENT
HAVING AN ARTICULATING END EFFECTOR, now U.S. Pat. No. 7,670,334,
which is incorporated herein by reference.
[0129] The end effector 2012 includes in this example, among other
things, a staple channel 2022 and a pivotally translatable clamping
member, such as an anvil 2024, which are maintained at a spacing
that assures effective stapling and severing of tissue clamped in
the end effector 2012. The handle 2006 includes a pistol grip 2026
towards which a closure trigger 2018 is pivotally drawn by the
clinician to cause clamping or closing of the anvil 2024 toward the
staple channel 2022 of the end effector 2012 to thereby clamp
tissue positioned between the anvil 2024 and channel 2022. The
firing trigger 2020 is farther outboard of the closure trigger
2018. Once the closure trigger 2018 is locked in the closure
position, the firing trigger 2020 may rotate slightly toward the
pistol grip 2026 so that it can be reached by the operator using
one hand. Then the operator may pivotally draw the firing trigger
2020 toward the pistol grip 2026 to cause the stapling and severing
of clamped tissue in the end effector 2012. The '573 application
describes various configurations for locking and unlocking the
closure trigger 2018. In other embodiments, different types of
clamping members besides the anvil 2024 could be used, such as, for
example, an opposing jaw, etc.
[0130] It will be appreciated that the terms "proximal" and
"distal" are used herein with reference to a clinician gripping the
handle 2006 of the instrument 2010. Thus, the end effector 2012 is
distal with respect to the more proximal handle 2006. It will be
further appreciated that, for convenience and clarity, spatial
terms such as "vertical" and "horizontal" are used herein with
respect to the drawings. However, surgical instruments are used in
many orientations and positions, and these terms are not intended
to be limiting and absolute.
[0131] The closure trigger 2018 may be actuated first. Once the
clinician is satisfied with the positioning of the end effector
2012, the clinician may draw back the closure trigger 2018 to its
fully closed, locked position proximate to the pistol grip 2026.
The firing trigger 2020 may then be actuated. When the clinician
removes pressure from the firing trigger 2020, it returns to the
open position (shown in FIGS. 23 and 24). A release button 2030 on
the handle 2006, and in this example, on the pistol grip 2026 of
the handle, when depressed may release the locked closure trigger
2018.
[0132] FIG. 25 is an exploded view of the end effector 2012
according to various embodiments. As shown in the illustrated
embodiment, the end effector 2012 may include, in addition to the
previously-mentioned channel 2022 and anvil 2024, a cutting
instrument 2032, a sled 2033, a staple cartridge 2034 that is
removably seated in the channel 2022, and a helical screw shaft
2036. The second element 2035 may be coupled or formed integrally
with a component of interest. The cutting instrument 2032 may be,
for example, a knife. The anvil 2024 may be pivotably opened and
closed at a pivot point 2025 connected to the proximate end of the
channel 2022. The anvil 2024 may also include a tab 2027 at its
proximate end that is inserted into a component of the mechanical
closure system (described further below) to open and close the
anvil 2024. When the closure trigger 2018 is actuated, that is,
drawn in by a user of the instrument 2010, the anvil 2024 may pivot
about the pivot point 2025 into the clamped or closed position. If
clamping of the end effector 2012 is satisfactory, the operator may
actuate the firing trigger 2020, which, as explained in more detail
below, causes the knife 2032 and sled 2033 to travel longitudinally
along the channel 2022, thereby cutting tissue clamped within the
end effector 2012. The movement of the sled 2033 along the channel
2022 causes the staples of the staple cartridge 2034 to be driven
through the severed tissue and against the closed anvil 2024, which
turns the staples to fasten the severed tissue. U.S. Pat. No.
6,978,921, entitled SURGICAL STAPLING INSTRUMENT INCORPORATING AN
E-BEAM FIRING MECHANISM, which is incorporated herein by reference,
provides more details about such two-stroke cutting and fastening
instruments. The sled 2033, which may comprise the second element
2035, may be part of the cartridge 2034, such that when the knife
2032 retracts following the cutting operation, the sled 2033 and
the second element 2035 do not retract. The cartridge 2034 could be
made of a nonconductive material (such as plastic). In one
embodiment, the second element 2035 may be connected to or disposed
in the cartridge 2034, for example. In the illustrated embodiment,
the second element 2035 may be attached to the sled 2033 in any
suitable manner and on any suitable portion thereof. In other
embodiments, the second element 2035 may be embedded in the sled
2033 or otherwise integrally formed (e.g., co-molded) with the sled
2033. Accordingly, the location of the sled 2033 may be determined
by detecting the location of the second element 2035. The second
element 2035 may be formed of various materials in various sizes
and shapes and may be located at certain predetermined distances
from the first element 2021 to enable the control unit 2300 to
ascertain the type, presence and status of the staple cartridge
2034.
[0133] It should be noted that although the embodiments of the
instrument 2010 described herein employ an end effector 2012 that
staples the severed tissue, in other embodiments different
techniques for fastening or sealing the severed tissue may be used.
For example, end effectors that use RF energy or adhesives to
fasten the severed tissue may also be used. U.S. Pat. No.
5,709,680, entitled ELECTROSURGICAL HEMOSTATIC DEVICE, and U.S.
Pat. No. 5,688,270, entitled ELECTROSURGICAL HEMOSTATIC DEVICE WITH
RECESSED AND/OR OFFSET ELECTRODES, which are incorporated herein by
reference, discloses cutting instruments that use RF energy to
fasten the severed tissue. U.S. patent application Ser. No.
11/267,811, now U.S. Pat. No. 7,673,783 and U.S. patent application
Ser. No. 11/267,383, now U.S. Pat. No. 7,607,557, which are also
incorporated herein by reference, disclose cutting instruments that
use adhesives to fasten the severed tissue. Accordingly, although
the description herein refers to cutting/stapling operations and
the like, it should be recognized that this is an exemplary
embodiment and is not meant to be limiting. Other tissue-fastening
techniques may also be used.
[0134] FIGS. 26 and 27 are exploded views and FIG. 28 is a side
view of the end effector 2012 and shaft 2008 according to various
embodiments. As shown in the illustrated embodiment, the shaft 2008
may include a proximate closure tube 2040 and a distal closure tube
2042 pivotably linked by a pivot links 2044. The distal closure
tube 2042 includes an opening 2045 into which the tab 2027 on the
anvil 2024 is inserted in order to open and close the anvil 2024.
Disposed inside the closure tubes 2040, 2042 may be a proximate
spine tube 2046. Disposed inside the proximate spine tube 2046 may
be a main rotational (or proximate) drive shaft 2048 that
communicates with a secondary (or distal) drive shaft 2050 via a
bevel gear assembly 2052. In the illustrated embodiment, the first
element 2021 may be a coil disposed about the proximate spine tube
2046 (e.g., as shown in FIGS. 26 and 27). In a wired electrical
connection configuration, the first element 2021 may be connected
to the control unit 2300 by way of the wired electrical connection
2023, which may comprise lengths of wire forming the coil. The
lengths of wire may be provided along the proximate spine tube 2046
to connect to the control unit 2300. In a wireless electrical
connection configuration, a wire is not necessary and the
electrical connection 2023 to the control unit 2300 is a wireless
electrical connection. In one embodiment, the first element 2021
may be contained within the proximate spine tube 2046 (e.g., as
shown in FIG. 28). In either case, the first element 2021 is
electrically isolated from the proximate spine tube 2046.
[0135] The secondary drive shaft 2050 is connected to a drive gear
2054 that engages a proximate drive gear 2056 of the helical screw
shaft 2036. The vertical bevel gear 2052b may sit and pivot in an
opening 2057 in the distal end of the proximate spine tube 2046. A
distal spine tube 2058 may be used to enclose the secondary drive
shaft 2050 and the drive gears 2054, 2056. Collectively, the main
drive shaft 2048, the secondary drive shaft 2050, and the
articulation assembly (e.g., the bevel gear assembly 2052a-c), are
sometimes referred to herein as the "main drive shaft assembly."
Components of the main drive shaft assembly (e.g., the drive shafts
2048, 2050) may be made of a nonconductive material (such as
plastic).
[0136] A bearing 2038, positioned at a distal end of the staple
channel 2022, receives the helical drive screw 2036, allowing the
helical drive screw 2036 to freely rotate with respect to the
channel 2022. The helical screw shaft 2036 may interface a threaded
opening (not shown) of the knife 2032 such that rotation of the
shaft 2036 causes the knife 2032 to translate distally or
proximately (depending on the direction of the rotation) through
the staple channel 2022. Accordingly, when the main drive shaft
2048 is caused to rotate by actuation of the firing trigger 2020
(as explained in more detail below), the bevel gear assembly
2052a-c causes the secondary drive shaft 2050 to rotate, which in
turn, because of the engagement of the drive gears 2054, 2056,
causes the helical screw shaft 2036 to rotate, which causes the
knife 2032 to travel longitudinally along the channel 2022 to cut
any tissue clamped within the end effector. The sled 2033 may be
made of, for example, plastic, and may have a sloped distal
surface. As previously discussed, the second element 2035 may be
attached to the sled 2033 in any suitable manner to determine the
status, location and type of the sled 2033 and/or the staple
cartridge 2034. As the sled 2033 traverses the channel 2022, the
sloped forward surface may push up or drive the staples in the
staple cartridge 2034 through the clamped tissue and against the
anvil 2024. The anvil 2024 turns the staples, thereby stapling the
severed tissue. When the knife 2032 is retracted, the knife 2032
and sled 2033 may become disengaged, thereby leaving the sled 2033
at the distal end of the channel 2022.
[0137] According to various embodiments, as shown FIGS. 29-32, the
surgical instrument may include a battery 2064 in the handle 2006.
The illustrated embodiment provides user-feedback regarding the
deployment and loading force of the cutting instrument in the end
effector 2012. In addition, the embodiment may use power provided
by the user in retracting the firing trigger 2018 to power the
instrument 2010 (a so-called "power assist" mode). As shown in the
illustrated embodiment, the handle 2006 includes exterior lower
side pieces 2059, 2060 and exterior upper side pieces 2061, 2062
that fit together to form, in general, the exterior of the handle
2006. The handle pieces 2059-2062 may be made of an electrically
nonconductive material, such as plastic. A battery 2064 may be
provided in the pistol grip portion 2026 of the handle 2006. The
battery 2064 powers a motor 2065 disposed in an upper portion of
the pistol grip portion 2026 of the handle 2006. The battery 2064
may be constructed according to any suitable construction or
chemistry including, for example, a Li-ion chemistry such as
LiCoO.sub.2 or LiNiO.sub.2, a Nickel Metal Hydride chemistry, etc.
According to various embodiments, the motor 2065 may be a DC
brushed driving motor having a maximum rotation of, approximately,
5000 to 100,000 RPM. The motor 2065 may drive a 90.degree. bevel
gear assembly 2066 comprising a first bevel gear 2068 and a second
bevel gear 2070. The bevel gear assembly 2066 may drive a planetary
gear assembly 2072. The planetary gear assembly 2072 may include a
pinion gear 2074 connected to a drive shaft 2076. The pinion gear
2074 may drive a mating ring gear 2078 that drives a helical gear
drum 2080 via a drive shaft 20082. A ring 2084 may be threaded on
the helical gear drum 2080. Thus, when the motor 2065 rotates, the
ring 2084 is caused to travel along the helical gear drum 2080 by
means of the interposed bevel gear assembly 2066, planetary gear
assembly 2072 and ring gear 2078.
[0138] The handle 2006 may also include a run motor sensor 2110 in
communication with the firing trigger 2020 to detect when the
firing trigger 2020 has been drawn in (or "closed") toward the
pistol grip portion 2026 of the handle 2006 by the operator to
thereby actuate the cutting/stapling operation by the end effector
2012. The sensor 2110 may be a proportional sensor such as, for
example, a rheostat or variable resistor. When the firing trigger
2020 is drawn in, the sensor 2110 detects the movement, and sends
an electrical signal indicative of the voltage (or power) to be
supplied to the motor 2065. When the sensor 2110 is a variable
resistor or the like, the rotation of the motor 2065 may be
generally proportional to the amount of movement of the firing
trigger 2020. That is, if the operator only draws or closes the
firing trigger 2020 in a little bit, the rotation of the motor 2065
is relatively low. When the firing trigger 2020 is fully drawn in
(or in the fully closed position), the rotation of the motor 2065
is at its maximum. In other words, the harder the user pulls on the
firing trigger 2020, the more voltage is applied to the motor 2065,
causing greater rates of rotation.
[0139] The handle 2006 may include a middle handle piece 2104
adjacent to the upper portion of the firing trigger 2020. The
handle 2006 also may comprise a bias spring 2112 connected between
posts on the middle handle piece 2104 and the firing trigger 2020.
The bias spring 2112 may bias the firing trigger 2020 to its fully
open position. In that way, when the operator releases the firing
trigger 2020, the bias spring 2112 will pull the firing trigger
2020 to its open position, thereby removing actuation of the sensor
2110, thereby stopping rotation of the motor 2065. Moreover, by
virtue of the bias spring 2112, any time a user closes the firing
trigger 2020, the user will experience resistance to the closing
operation, thereby providing the user with feedback as to the
amount of rotation exerted by the motor 2065. Further, the operator
could stop retracting the firing trigger 2020 to thereby remove
force from the sensor 2110, to thereby stop the motor 2065. As
such, the user may stop the deployment of the end effector 2012,
thereby providing a measure of control of the cutting/fastening
operation to the operator.
[0140] The distal end of the helical gear drum 2080 includes a
distal drive shaft 2120 that drives a ring gear 2122, which mates
with a pinion gear 2124. The pinion gear 2124 is connected to the
main drive shaft 2048 of the main drive shaft assembly. In that
way, rotation of the motor 2065 causes the main drive shaft
assembly to rotate, which causes actuation of the end effector
2012, as described above.
[0141] The ring 2084 threaded on the helical gear drum 2080 may
include a post 2086 that is disposed within a slot 2088 of a
slotted arm 2090. The slotted arm 2090 has an opening 2092 at its
opposite end 2094 that receives a pivot pin 2096 that is connected
between the handle exterior side pieces 2059, 2060. The pivot pin
2096 is also disposed through an opening 2100 in the firing trigger
2020 and an opening 2102 in the middle handle piece 2104.
[0142] In addition, the handle 2006 may include a reverse motor (or
end-of-stroke sensor) 2130 and a stop motor (or
beginning-of-stroke) sensor 2142. In various embodiments, the
reverse motor sensor 2130 may be a limit switch located at the
distal end of the helical gear drum 2080 such that the ring 2084
threaded on the helical gear drum 2080 contacts and trips the
reverse motor sensor 2130 when the ring 2084 reaches the distal end
of the helical gear drum 2080. The reverse motor sensor 2130, when
activated, sends a signal to the control unit which sends a signal
to the motor 2065 to reverse its rotation direction, thereby
withdrawing the knife 2032 of the end effector 2012 following the
cutting operation.
[0143] The stop motor sensor 2142 may be, for example, a
normally-closed limit switch. In various embodiments, it may be
located at the proximate end of the helical gear drum 2080 so that
the ring 2084 trips the switch 2142 when the ring 2084 reaches the
proximate end of the helical gear drum 2080.
[0144] The handle 2006 also may comprise the control unit 2300. The
control unit 2300 may be powered through the battery 2064 with the
addition of a conditioning circuit (not shown). The control unit
2300 is coupled to the first element 2021 by an electrical
connection 2023. As previously discussed, the electrical connection
2023 may be a wired electrical connection or a wireless electrical
connection.
[0145] In operation, when an operator of the instrument 2010 pulls
back the firing trigger 2020, the sensor 2110 detects the
deployment of the firing trigger 2020 and sends a signal to the
control unit which sends a signal to the motor 2065 to cause
forward rotation of the motor 2065 at, for example, a rate
proportional to how hard the operator pulls back the firing trigger
2020. The forward rotation of the motor 2065 in turn causes the
ring gear 2078 at the distal end of the planetary gear assembly
2072 to rotate, thereby causing the helical gear drum 2080 to
rotate, causing the ring 2084 threaded on the helical gear drum
2080 to travel distally along the helical gear drum 2080. The
rotation of the helical gear drum 2080 also drives the main drive
shaft assembly as described above, which in turn causes deployment
of the knife 2032 in the end effector 2012. That is, the knife 2032
and the sled 2033 are caused to traverse the channel 2022
longitudinally, thereby cutting tissue clamped in the end effector
2012. Also, the stapling operation of the end effector 2012 is
caused to happen in embodiments where a stapling-type end effector
is used.
[0146] By the time the cutting/stapling operation of the end
effector 2012 is complete, the ring 2084 on the helical gear drum
2080 will have reached the distal end of the helical gear drum
2080, thereby causing the reverse motor sensor 2130 to be tripped,
which sends a signal to the control unit which sends a signal to
the motor 2065 to cause the motor 2065 to reverse its rotation.
This in turn causes the knife 2032 to retract, and also causes the
ring 2084 on the helical gear drum 2080 to move back to the
proximate end of the helical gear drum 2080.
[0147] The middle handle piece 2104 includes a backside shoulder
2106 that engages the slotted arm 2090 as best shown in FIGS. 30
and 31. The middle handle piece 2104 also has a forward motion stop
2107 that engages the firing trigger 2020. The movement of the
slotted arm 2090 is controlled, as explained above, by rotation of
the motor 2065. When the slotted arm 2090 rotates CCW as the ring
2084 travels from the proximate end of the helical gear drum 2080
to the distal end, the middle handle piece 2104 will be free to
rotate CCW. Thus, as the user draws in the firing trigger 2020, the
firing trigger 2020 will engage the forward motion stop 2107 of the
middle handle piece 2104, causing the middle handle piece 2104 to
rotate CCW. Due to the backside shoulder 2106 engaging the slotted
arm 2090, however, the middle handle piece 2104 will only be able
to rotate CCW as far as the slotted arm 2090 permits. In that way,
if the motor 2065 should stop rotating for some reason, the slotted
arm 2090 will stop rotating, and the user will not be able to
further draw in the firing trigger 2020 because the middle handle
piece 2104 will not be free to rotate CCW due to the slotted arm
2090.
[0148] Components of an exemplary closure system for closing (or
clamping) the anvil 2024 of the end effector 2012 by retracting the
closure trigger 2018 are also shown in FIGS. 29-32. In the
illustrated embodiment, the closure system includes a yoke 2250
connected to the closure trigger 2018 by a pin 2251 that is
inserted through aligned openings in both the closure trigger 2018
and the yoke 2250. A pivot pin 2252, about which the closure
trigger 2018 pivots, is inserted through another opening in the
closure trigger 2018 which is offset from where the pin 2251 is
inserted through the closure trigger 2018. Thus, retraction of the
closure trigger 2018 causes the upper part of the closure trigger
2018, to which the yoke 2250 is attached via the pin 2251, to
rotate CCW. The distal end of the yoke 2250 is connected, via a pin
2254, to a first closure bracket 2256. The first closure bracket
2256 connects to a second closure bracket 2258. Collectively, the
closure brackets 2256, 2258 define an opening in which the
proximate end of the proximate closure tube 2040 (FIG. 26) is
seated and held such that longitudinal movement of the closure
brackets 2256, 2258 causes longitudinal motion by the proximate
closure tube 2040. The instrument 2010 also includes a closure rod
2260 disposed inside the proximate closure tube 2040. The closure
rod 2260 may include a window 2261 into which a post 2263 on one of
the handle exterior pieces, such as exterior lower side piece 2059
in the illustrated embodiment, is disposed to fixedly connect the
closure rod 2260 to the handle 2006. In that way, the proximate
closure tube 2040 is capable of moving longitudinally relative to
the closure rod 2260. The closure rod 2260 may also include a
distal collar 2267 that fits into a cavity 2269 in proximate spine
tube 2046 and is retained therein by a cap 2271 (FIG. 26).
[0149] In operation, when the yoke 2250 rotates due to retraction
of the closure trigger 2018, the closure brackets 2256, 2258 cause
the proximate closure tube 2040 to move distally (i.e., away from
the handle end of the instrument 2010), which causes the distal
closure tube 2042 to move distally, which causes the anvil 2024 to
rotate about the pivot point 2025 into the clamped or closed
position. When the closure trigger 2018 is unlocked from the locked
position, the proximate closure tube 2040 is caused to slide
proximately, which causes the distal closure tube 2042 to slide
proximately, which, by virtue of the tab 2027 being inserted in the
window 2045 of the distal closure tube 2042, causes the anvil 2024
to pivot about the pivot point 2025 into the open or unclamped
position. In that way, by retracting and locking the closure
trigger 2018, an operator may clamp tissue between the anvil 2024
and channel 2022, and may unclamp the tissue following the
cutting/stapling operation by unlocking the closure trigger 2018
from the locked position.
[0150] The control unit 2300 (described further below) may receive
the outputs from end-of-stroke and beginning-of-stroke sensors
2130, 2142 and the run-motor sensor 2110, and may control the motor
2065 based on the inputs. For example, when an operator initially
pulls the firing trigger 2020 after locking the closure trigger
2018, the run-motor sensor 2110 is actuated. If the staple
cartridge 2034 is present in the end effector 2012, a cartridge
lockout sensor (not shown) may be closed, in which case the control
unit may output a control signal to the motor 2065 to cause the
motor 2065 to rotate in the forward direction. When the end
effector 2012 reaches the end of its stroke, the reverse motor
sensor 2130 will be activated. The control unit may receive this
output from the reverse motor sensor 2130 and cause the motor 2065
to reverse its rotational direction. When the knife 2032 is fully
retracted, the stop motor sensor switch 2142 is activated, causing
the control unit to stop the motor 2065.
[0151] In other embodiments, rather than a proportional-type sensor
2110, an on-off type sensor may be used. In such embodiments, the
rate of rotation of the motor 2065 would not be proportional to the
force applied by the operator. Rather, the motor 2065 would
generally rotate at a constant rate. But the operator would still
experience force feedback because the firing trigger 2020 is geared
into the gear drive train.
[0152] The instrument 2010 may include a number of sensor elements
in the end effector 2012 for sensing various conditions related to
the end effector 2012, such as sensor elements for determining the
status of the staple cartridge 2034 (or other type of cartridge
depending on the type of surgical instrument), the progress of the
stapler during closure and firing, etc. The sensor elements may be
passively powered by inductively coupled signals, as described in
commonly assigned U.S. patent application Ser. No. 11/651,715,
entitled SURGICAL INSTRUMENT WITH WIRELESS COMMUNICATION BETWEEN
CONTROL UNIT AND SENSOR TRANSPONDERS, now U.S. Pat. No. 8,652,120,
which is incorporated herein by reference. In other embodiments,
the sensor elements reflect or scatter incident electromagnetic
energy or power up in response to the interrogation signal and
transmit echo response pulses or signals that may be coupled back
to the control unit 2300 for processing. In other embodiments, the
sensor elements may be powered by the minute electrical current
induced in the sensor element itself or an antenna coupled to the
sensor element by the incoming incident electromagnetic energy
(e.g., the RF carrier of the interrogation signal) transmitted by
the control unit 2300. These sensor elements may comprise any
arrangement of electrical conductors to transmit, receive, amplify,
encode, scatter and/or reflect electromagnetic energy waves of any
suitable predetermined frequency (e.g., wavelength [.lamda.]),
having a suitable predetermined pulse width that may be transmitted
over a suitable predetermined time period. The passive sensor
elements may comprise any suitable arrangement of resistive,
inductive, and/or capacitive elements. The active sensor elements
may comprise semiconductors such as transistors, integrated
circuits, processors, amplifiers and/or any combination of these
active elements. For succinctness the passive and/or active sensor
elements are referred to hereinafter as the first element 2021 and
the second element 2035. The first element 2021 may be in wired or
wireless communication with the control unit 2300, which, as
previously discussed, may be housed in the handle 2006 of the
instrument 2010, for example, as shown below in FIG. 33. The first
element 2021 is in wireless communication with the second element
2035.
[0153] FIG. 33 illustrates a schematic block diagram of one
embodiment of the control unit 2300. According to various
embodiments, the control unit 2300 may comprise a processor 2306
and one or more memory units 2308. By executing instruction code
stored in the memory 2308, the processor 2306 may control various
components of the instrument 2010, such as the motor 2065 or a user
display (not shown), based on inputs received from the one or more
end effector sensor element(s) and/or other sensor elements located
throughout the instrument 2010 (such as the run-motor sensor 2110,
the end-of-stroke sensor 2130, and the beginning-of-stroke sensor
2142, for example). The control unit 2300 may be powered by the
battery 2064 during surgical use of the instrument 2010. The
control unit 2300 may be coupled to the first element 2021 over the
electrical connection 2023 and may communicate with the second
element 2035, as described in more detail below. The control unit
2300 may comprise a transmitter 2320 and a receiver 2322. The first
element 2021 may be coupled to the transmitter 2320 to transmit an
output interrogation signal or may be coupled to the receiver 2322
to receive an echo response signal in accordance with the operation
of a switch 2324.
[0154] The switch 2324 may operate under the control of the
processor 2306, the transmitter 2320 or the receiver 2322 or any
combination thereof to place the control unit 2300 either in
transmitter or receiver mode. In transmitter mode, the switch 2324
couples the first element 2021 to the transmitter 2320 and thus the
first element 2021 acts as a transmitting antenna. An encoder 2316
encodes the output interrogation signal to be transmitted, which is
then modulated by a modulator 2318. An oscillator 2326 coupled to
the modulator 2318 sets the operating frequency for the output
signal to be transmitted. In receiver mode, the switch 2324 couples
the first element 2021 to the receiver 2322. Accordingly, the first
element 2021 acts as a receiving antenna and receives input signals
from the other sensor elements (e.g., the second element 2035). The
received input signals may be demodulated by a demodulator 2310 and
decoded by a decoder 2312. The input signals may comprise echo
response signals from one or more of the sensor elements (e.g., the
second element 2035). The echo response signals may comprise
information associated with the location, type, presence and/or
status of various components located in the end effector 2012 or in
other location in the instrument 2010. The echo signals, for
example, may comprise signals reflected by the second element 2035,
which may be attached to the sled 2033, the staple cartridge 2034
or any other component located in the end effector 2012 or may be
located on any component of interest on any portion of the
instrument 2010. The echo signal data reflected from the second
element 2035 may be used by the processor 2306 to control various
aspects of the instrument 2010.
[0155] To transmit an output signal from the first element 2021 to
the second element 2035, the control unit 2300 may employ the
encoder 2316 for encoding the output signals and the modulator 2318
for modulating the output signals according to a predetermined
modulation scheme. As previously discussed, in transmitter mode,
the first element 2021 is coupled to the transmitter 2320 through
the switch 2324 and acts as a transmitting antenna. The encoder
2316 may comprise a timing unit to generate timing pulses at a
predetermined suitable pulse repetition frequency. These timing
pulses may be applied to the modulator 2318 to trigger the
transmitter at precise and regularly occurring instants of time.
Thus, in one embodiment, the modulator 2318 may produce rectangular
pulses of known pulse duration to switch the oscillator 2326 on and
off. In accordance with the modulation scheme, the oscillator 2326
produces short duration pulses of a predetermined power and
frequency (or wavelength .lamda.) set by the oscillator 2326. The
pulse repetition frequency may be determined by the encoder 2312
and the pulse duration may be determined by the modulator 2318. The
switch 2324 under control of the control unit 2300 automatically
connects the transmitter 2320 to the first element 2021 for the
duration of each output pulse. In transmission mode, the first
element 2021 radiates the transmitter 2320 output pulse signal and
picks up or detects the reflected echo signals for application to
the receiver 2322. In receiver mode, the switch 2324 connects the
first element 2021 to the receiver 2322 for the intervals between
transmission pulses. The receiver 2322 receives echo signals of the
transmitted pulse output signals that may be reflected from one or
more sensor elements located on the instrument such as the second
element 2035 attached to the sled 2033. The receiver 2322 amplifies
the echo signals and presents them to the demodulator 2310 in
suitable form. Subsequently, the demodulated echo signals are
provided to the decoder 2312 where they are correlated with the
transmitted output pulse signals to determine the location, type,
presence and/or status of various components located in the end
effector 2012. In addition, the distance between the first and
second elements 2021, 2035 may be determined
[0156] The control unit 2300 may communicate with the first element
2021 using any suitable wired or wireless communication protocol
and any suitable frequency (e.g., an ISM band). The control unit
2300 may transmit output pulse signals in various frequency ranges.
Although in the illustrated embodiment, only the first element 2021
is shown to perform the transmission and reception functions, in
other embodiments the control unit 2300 may comprise separate
receiving and transmitting elements, for example.
[0157] According to various embodiments, the control unit 2300 may
be implemented using integrated and/or discrete hardware elements,
software elements, or a combination of both. Examples of integrated
hardware elements may include processors, microprocessors,
microcontrollers, integrated circuits, application specific
integrated circuits (ASIC), programmable logic devices (PLD),
digital signal processors (DSP), field programmable gate arrays
(FPGA), logic gates, registers, semiconductor devices, chips,
microchips, chip sets, microcontroller, system-on-chip (SoC) or
system-in-package (SIP). Examples of discrete hardware elements may
include circuits, circuit elements (e.g., logic gates, field effect
transistors, bipolar transistors, resistors, capacitors, inductors,
relay and so forth). In other embodiments, the control unit 2300
may be embodied as a hybrid circuit comprising discrete and
integrated circuit elements or components on one or more
substrates. In various embodiments, the control unit 2300 may
provide a digital (e.g., on/off, high/low) output and/or an analog
output to a motor control unit. The motor control unit also may be
embodied using elements and/or components similar to the control
unit 2300. The motor control unit may be used to control the motor
2065 in response to the radiated echo response signals from the one
or more passive and/or active sensor elements.
[0158] Referring back to FIGS. 23-28, in one embodiment, the first
element 2021 may be an inductive element (e.g., a first coil)
coupled to the control unit 2300 by the wired electrical connection
2023. The wired electrical connection 2023 may be an electrically
conductive insulated wire. The second element 2035 also may be an
inductive element (e.g., a second coil) embedded, integrally formed
with or otherwise attached to the sled 2033. The second element
2035 is wirelessly coupled to the first element 2021. The first
element 2021 is preferably electrically insulated from the
conductive shaft 2008. The second element 2035 is preferably
electrically insulated from the sled 2033 and other components
located in the staple cartridge 2034 and/or the staple channel
2022. The second element 2035 receives the output pulse signal
transmitted by the first element 2021 and reflects or scatters the
electromagnetic energy in the form of an echo signal. By varying
the material, size, shape and location of the second element 2035
relative to the first element 2021, the control unit 2300 can
determine the location, type, presence and/or status of various
components located in the end effector 2012 by decoding the echo
signals reflected therefrom.
[0159] FIG. 34 is a schematic diagram 2400 illustrating the
operation of one embodiment of the control unit 2300 in conjunction
with the first and second elements 2021, 2035. The following
description also references FIG. 33. The first element 2021 is
coupled to the control unit 2300 by a channel, e.g., the electrical
connection 2023. The electrical connection 2023 may be a wired or
wireless channel. As previously discussed, the first element 2021
wirelessly interrogates or illuminates the second element 2035 by
transmitting an interrogation signal in the form of one or more
interrogation pulses 2402. The interrogation pulses 2402 may be of
a suitable predetermined frequencyf as may be determined by the
oscillator 2326. The interrogation pulses 2402 may have a
predetermined pulse width PW as may be determined by the modulator
2318 and may be transmitted at a pulse repetition rate T as may be
determined by the encoder 2316. The transmitted interrogation
pulses 2402 that are incident upon (e.g., strike or illuminate) the
second element 2035 is reflected or scattered by the second element
2035 in the form of echo response pulses 2404. The echo response
pulses 2404 are electromagnetic energy reflections of the
interrogation pulses 2402 incident upon the second element 2021,
but much weaker in signal strength. After transmitting the
interrogation pulses 2402, the first element 2021 listens for the
echo response pulses 2404 and couples the echo response pulses 2402
to the control unit 2300 in a suitable form. The demodulator 2310
receives the weak echo response pulses 2404 and amplifies and
demodulates them. The decoder 2312 and the processor 2306 process
the received echo response pulses 2404 to extract information
therefrom. The processor 2306 (or other logic) may be programmed to
ascertain various properties associated with the end effector 2012
and components in accordance with the received echo response pulses
2404.
[0160] The frequency f, PW and T of the echo response pulses 2404
may be the same as the interrogation pulses 2402. In various
embodiments, the frequency f, PW and T of the echo response pulses
2404 may be different than the interrogation pulses 2402. In one
embodiment, the frequency f, for example, of the echo response
pulses 2404 may be a harmonic frequency of the interrogation pulse
2402 frequency. The amount of reflected electromagnetic energy in
the echo response pulses 2404 depends upon the material, shape and
size of the second element 2035. The amount of reflected
electromagnetic energy in the echo response pulses 2404 also
depends upon the distance D between the first element 2021 and the
second element 2035.
[0161] The material that the second element 2035 is formed of may
determine the amount of reflected energy. For example, a metal
object will reflect more energy than an object of the same size and
shape made of wood, plastic, etc. In general, the better the
electrical conductive properties of the material the greater is the
reflection. The shape of the second element 2035 also may determine
how the energy is reflected or scattered. For example, if the
second element 2035 has a flat side facing the first element 2021,
the second element 2035 may reflect more energy back towards the
first element 2021. A circular object may reflect or scatter the
energy in the various directions normal to the surface struck by
the incident electromagnetic energy and an object with
irregularities will scatter the incident electromagnetic energy
more randomly. The size of the second element 2021 also may
determine the amount of reflected energy. For example, a larger
second element 2035 will reflect more energy than a smaller second
element 2035 of the same material and shape and at the same
distance D from the first element 2021. It will be appreciated that
the second element 2035 should have a certain minimum size relative
to the wavelength (.lamda.) of the radiated electromagnetic energy
of the interrogation pulses 2402 to produce practical reflected
echo response pulses 2404. For example, the size of the second
element 2035 may be equal to or greater than about a quarter of the
wavelength (.lamda./4) of the electromagnetic energy of the
interrogation pulses 2402. The wavelength .lamda. of the
transmitted interrogation pulses 2402 is related to the frequency f
in accordance with the equation: .lamda.=c/J; where c is the speed
of light and f is the signal frequency. Therefore, to detect small
objects the wavelength .lamda. must be small and thus the frequency
f must be high. Any suitable predetermined frequency f may be
selected to accommodate the size of the second element 2035 to be
detected. Accordingly, the size of the second element 2035 may be
selected to be greater than or equal to .lamda./4 (or c/4f), for
example, once the interrogation pulse 2402 frequency is determined.
As previously discussed, the amount of energy reflected by the
second element 2035 also depends on the distance D between the
first element 2021 and the second element 2035.
[0162] Accordingly, the material, shape and size of the second
element 2035 and the relative distance D between it and the first
element 2021 may be selected to generate unique echo response
pulses 2404 that may be indicative of a desired measurement
associated with the second element 2035. For example, unique echo
response pulses 2404 may indicate the location, type, presence
and/or status of various components and/or sub-components disposed
on the surgical instrument 2010. Especially the various components
and sub-components disposed in the end effector 2012 portion of the
surgical instrument 2010 subsequent to the articulation pivot 2014.
The echo response pulses 2404 also may be used to determine the
distance D between the first element 2021 and the second element
2035. In this manner, by integrating the second element 2035 or
attaching it to a components of interest, such as the sled 2033,
the echo response pulses 2404 may be processed by the control unit
2300 to extract and provide information associated with the
component of interest, such as the location, type, presence and/or
status of the sled 2033, the staple cartridge 2034, and so on. This
arrangement may eliminate the need to transmit or provide power
over a wired connection to the second element 2035 and may be a
cost effective solution to providing various sensor elements on the
surgical instrument 2010.
[0163] In one embodiment, where the second element 2035 is an
active sensor element, as previously discussed, the first element
2021 wirelessly interrogates or illuminates the second element 2035
by transmitting an interrogation signal in the form of one or more
interrogation pulses 2402. The electromagnetic energy in the
interrogation pulses 2402 are coupled by the sensor element 2035
and serve to power-up the sensor element 2035. Once powered-up, the
sensor element 2035 transmits the echo response pulses 2404 back to
the control unit 2300.
[0164] In one embodiment, the status of the staple cartridge 2034
and the location of the sled 2033 may be determined by transmitting
the interrogation pulse 2402 and listening for an echo response
pulse 2404. As previously discussed, the first and second elements
2021, 2035 may be passive sensors or electromagnetic elements
(which may comprise resistive, inductive and capacitive elements or
any combination thereof). In one embodiment, the first element 2021
may be an inductance in the form of a primary coil located at the
distal end of the shaft 2008 (as shown in FIGS. 23, 24, 26-28). The
second element 2035 may be an inductive element in the form of a
secondary coil located in the sled 2033 (as shown in FIGS. 25, 27,
28). The first element 2021 "pings" or transmits interrogation
pulses 2402. The echo response pulses 2404 reflected by the second
element 2035 may be indicative of the presence of the sled 2033 in
the staple channel 2022, its distance from the first element 2021
or its location longitudinally along the staple channel 2022. In
this manner, the instrument 2010 can determine the presence or
status of the staple cartridge 2034 or the sled 2033 in the end
effector 2012 or the longitudinal location of the sled 2033 along
the staple channel 2022. This information may be used to determine
the loaded status of the staple cartridge 2034, for example.
Further the second element 2035 may be formed of different
materials, in different shapes or sizes to produce a unique echo
response pulse 2404 that is indicative of the instrument 2010 type
or presence of the staple cartridge 2034 within the end effector
2012. This eliminates the need to include any powered memory or
sensor elements in the end effector 2012 to electronically
determine the type, presence or status of the staple cartridge 2034
in the end effector 2012.
[0165] In another embodiment, the second element 2035 may be
attached to the sled 2033 and the echo response pulse 2404 may be
used to determine whether the sled 2033 is located in a first
position at the proximal end of the staple channel 2022 or a second
position at the distal end of the staple channel 2022 or in any
intermediate positions therebetween. The control unit 2300 may be
determine the position of the sled 2033 based on the elapsed time
between transmitting the interrogation pulse 2402 and receiving the
echo response pulse 2404. If the sled 2033 is in the first position
the echo response pulse 2404 is received sooner than if the sled
2033 was located at the second position or any position
therebetween. For example, as the sled 2033 moves longitudinally
along the staple channel 2022 the response time of the received
echo response pulse 2404 relative to the transmitted interrogation
pulse 2402 increases. This information may be used by the control
unit 2300 to determine the intermediate location of the sled 2033
in the channel 2022 and provide some measure of control of the
cutting/fastening operation, such as inhibiting the
cutting/fastening operation if the sled 2033, or other component,
is not in a predetermined location.
[0166] In yet another embodiment, the control unit 2300 may provide
some measure of control of the cutting/fastening operation based on
whether or not an echo response pulse 2404 is received within a
predetermined time period. For example, if an echo response pulse
2404 is received within the predetermined period, the control unit
2300 determines that the sled 2033 in located in the proximate end
on the staple channel 2022. In contrast, if the no echo response
pulse 2404 is received within the predetermined period, the control
unit 2300 determines that the sled 2033 has moved away from the
proximate end to the distal end of the staple channel 2022 (e.g.,
the instrument has been fired). In this manner, if no echo response
pulse 2404 is received, the control unit 2300 may determine either
that the staple cartridge 2034 has been fired and, therefore, the
sled 2033 has moved away longitudinally from the proximate end of
the staple channel 2022 or that there is no staple cartridge 2034
loaded and, therefore, prevents the instrument 2010 (e.g., a
surgical stapler) from firing.
[0167] Although the first element 2021 is shown disposed at one end
of the elongate shaft 2008 near the articulation pivot 2014, the
first element 2021 may be disposed anywhere along the elongate
shaft 2008 and/or in the handle 2006 in suitable wireless or wired
communication with the second element 2035.
[0168] FIG. 35 illustrates one embodiment of the surgical
instrument 2010 comprising the first element 2021 located in the
free rotating joint 2029 portion of the shaft 2008. The following
description also references FIGS. 25, 27, 28 and 34. The first
element 2021 is coupled to the control unit 2300 via the electrical
connection 2023. Additional elements may be employed, for example,
when the surgical instrument 2010 has numerous complex mechanical
joints and where it would be difficult to maintain a direct wired
connection. In such cases, inductive couplings may be used to span
each such joint. For example, inductive couplers may be used on
both sides of the rotary joint 2029 and both sides of the
articulation pivot 2014, with an inductive element on the distal
side of the rotary joint 2029 connected by an electrical connection
to another inductive element on the proximate side of the
articulation pivot 2014. Accordingly, a third element 2328 and a
fourth element 2330 may be disposed on the shaft 2008. These
elements 2328, 2330 may disposed anywhere along the shaft 2008. The
third element 2328 may be disposed on the proximal end of the shaft
2008 just prior to the articulation control 2016. The fourth
element 2330 may be disposed on the distal end of the shaft 2008
just prior to the articulation pivot 2014. The third and fourth
elements 2328, 2330 may be coupled by an electrical connection
2332, which may be a wired or a wireless electrical connection. The
second element 2035 is disposed or attached to a component of
interest in the end effector 2012. The third element 2328 is
wirelessly coupled to the first element 2021 and receives
interrogation pulses 2402 therefrom. The third element 2328
transmits the interrogation pulse 2402 along the electrical
connection 2332 to the fourth element 2330. The fourth element 2330
wirelessly couples the interrogation pulse 2402 to the second
element 2035. The echo response pulses 2404 are transmitted back to
the first element 2021 in reverse order. For example, the echo
response pulse 2404 is wirelessly coupled to the fourth element
2330, is relayed to the third element 2328 via the electrical
connection 2332 and is then wirelessly coupled to the first element
2021. Similarly to the first and second elements 2021, 2035, the
third and fourth elements 2328, 2330 may be formed of passive
and/or active sensor elements (e.g., resistive, inductance,
capacitive and/or semiconductor elements). In one embodiment, the
third and fourth elements 2328, 2330 may be passive coils formed of
various materials and in various shapes and sizes or may comprise
semiconductor elements such as transistors to operate in active
mode.
[0169] FIG. 36 illustrates one embodiment of the surgical
instrument 2010 comprising sensor elements disposed at various
locations on the shaft. For example, the first element 2021 may be
disposed on the proximate end of the shaft 2008 just prior to the
articulation control 2016. The first element 2021 is wirelessly
coupled to the control unit 2300 via wireless electrical connection
2023. The third element 2328 and the fourth element 2330 are
disposed along the shaft 2008 subsequent to the articulation
control 2016 and prior to the articulation pivot 2014. The third
element 2328 may be disposed on the proximate end of the shaft 2008
subsequent to the articulation control 2016 and the fourth element
2330 may be disposed on the distal end of the elongate shaft 2008
prior to the articulation pivot 2014. The third and fourth elements
2328, 2330 are coupled by the electrical connection 2332, which may
be a wired or a wireless electrical connection. As previously
discussed, the second element 2035 may be disposed on a component
of interest located in the end effector 2012. The third element
2328 is wirelessly coupled to the first element 2021 and receives
the interrogation pulses 2402 therefrom. The third element 2328
transmits the interrogation pulse 2402 along the electrical
connection 2332 to the fourth element 2330. The fourth element 2330
wirelessly couples the interrogation pulse 2402 to the second
element 2035. The echo response pulses 2404 are transmitted back to
the first element 2021 in reverse order. For example, the echo
response pulse 2404 is wirelessly coupled to the fourth element
2330, is relayed to the third element 2328 via the electrical
connection 2332 and is wirelessly coupled to the first element 2021
thereafter.
[0170] FIG. 37 illustrates one embodiment of the instrument 2010
where the shaft serves as part of the antenna for the control unit
2300. Accordingly, the shaft 2008 of the instrument 2010, including
for example, the proximate closure tube 2040 and the distal closure
tube 2042, may collectively serve as part of an antenna for the
control unit 2300 by radiating the interrogation pulses 2402 to the
second element 2035 and receiving the echo response pulses 2404
reflected from the second element 2035. That way, signals to and
from the control unit 2300 and the second element 2035 disposed in
the end effector 2012 may be transmitted via the shaft 2008 of the
instrument 2010.
[0171] The proximate closure tube 2040 may be grounded at its
proximate end by the exterior lower and upper side pieces
2059-2062, which may be made of a nonelectrically conductive
material, such as plastic. The drive shaft assembly components
(including the main drive shaft 2048 and secondary drive shaft
2050) inside the proximate and distal closure tubes 2040, 2042 may
also be made of a nonelectrically conductive material, such as
plastic. Further, components of the end effector 2012 (such as the
anvil 2024 and the channel 2022) may be electrically coupled to (or
in direct or indirect electrical contact with) the distal closure
tube 2042 such that they may also serve as part of the antenna.
Further, the second element 2035 may be positioned such that it is
electrically insulated from the components of the shaft 2008 and
the end effector 2012 serving as the antenna. For example, the
second element 2035 may be positioned in the cartridge 2034, which
may be made of a nonelectrically conductive material, such as
plastic. Because the distal end of the shaft 2008 (such as the
distal end of the distal closure tube 2042) and the portions of the
end effector 2012 serving as the antenna may be relatively close in
distance to the second element 2035, the power for the transmitted
signals may be held at low levels, thereby minimizing or reducing
interference with other systems in the use environment of the
instrument 2010.
[0172] In such an embodiment, the control unit 2300 may be
electrically coupled to the shaft 2008 of the instrument 2010, such
as to the proximate closure tube 2040, by an electrically
conductive connection 2410 (e.g., a wire). Portions of the outer
shaft 2008, such as the closure tubes 2040, 2042, may therefore act
as part of an antenna for the control unit 2300 by radiating
signals in the form of interrogation pulses 2402 to the second
element 2035 and receiving radiated signals in the form of echo
response pulses 2404 from the second element 2035. The echo
response pulses 2404 received by the control unit 2300 may be
demodulated by the demodulator 2310 and decoded by the decoder 2312
as previously discussed. The echo response pulses 2404 may comprise
information from the second element 2035 such as, the location,
type, presence and/or status of various components disposed on the
end effector 2012 portion of the instrument 2010, which the
processor 2306 may use to control various aspects of the instrument
2010, such as the motor 2065 or a user display.
[0173] To transmit data signals to or from the second element 2035
in the end effector 2012, the electrical connection 2410 may
connect the control unit 2300 to components of the shaft 2008 of
the instrument 2010, such as the proximate closure tube 2040, which
may be electrically connected to the distal closure tube 2042. The
distal closure tube 2042 is preferably electrically insulated from
the remote sensor 2368, which may be positioned in the plastic
cartridge 2034. As mentioned before, components of the end effector
2012, such as the channel 2022 and the anvil 2024, may be
conductive and in electrical contact with the distal closure tube
2042 such that they, too, may serve as part of the antenna.
[0174] With the shaft 2008 acting as the antenna for the control
unit 2300, the control unit 2300 can communicate with the second
element 2035 in the end effector 2012 without a direct wired
connection. In addition, because the distances between shaft 2008
and the second element 2035 is fixed and known, the power levels
could be optimized for low levels to thereby minimize interference
with other systems in the use environment of the instrument
2010.
[0175] Although throughout this description, the second element
2035 is shown disposed in the articulating end effector 2012, the
second element 2035 may be disposed in any suitable location on the
instruments 2010 while maintaining wireless communication with the
first element 2021 (and/or the shaft 2008) at least on one portion
of the transmission or reception cycle. The second element 2035
also may be coupled to any component within the staple cartridge
2034.
[0176] The control unit 2300 may communicate with any of the first
2021, second 2035, third 2328 and fourth 2330 elements and
additional elements through complex mechanical joints like the
rotating joint 2029 without a direct wired connection, but rather
through a wireless connection where it may be difficult to maintain
a wired connection. In addition, because the distances between the
first, second, third, fourth 2021, 2035, 2328, 2330 elements, and
any additional elements and/or any combination thereof, may be
fixed and known the couplings between these elements 2021, 2035,
2328, 2330 may be optimized for efficient inductive transfer of
electromagnetic energy. Also, these distances may be relatively
short so that relatively low power signals may be used and minimize
interference with other systems in the use environment of the
instrument 2010.
[0177] In other embodiments, more or fewer sensor elements may be
inductively, electromagnetically and/or otherwise coupled. For
example, in some embodiments, the control unit 2300 may comprise
the first element 2021 formed integrally therewith. The first
element 2021 in the handle 2006 and the second element 2035 in the
end effector 2012 can communicate directly without the third and
fourth elements 2328, 2330. Of course, in such an embodiment, a
stronger signal may be required due to the greater distance between
the control unit 2300 in the handle 2006 and the second element
2035 in the end effector 2012.
[0178] In the embodiments described above, the battery 2064 (FIG.
29) powers (at least partially) the firing operation of the
instrument 2010. As such, the instrument 2010 may be a so-called
"power-assist" device. More details and additional embodiments of
power-assist devices are described in the '573 application, which
is incorporated herein by reference. It should be recognized,
however, that the instrument 2010 need not be a power-assist device
and that this is merely an example of a type of device that may
utilize aspects of the present invention. For example, the
instrument 2010 may include a user display (such as a LCD or LED
display) that is powered by the battery 2064 and controlled by the
control unit 2300. Data from the sensor transponders 2368 in the
end effector 2012 may be displayed on such a display.
[0179] FIGS. 38 and 39 depict a surgical cutting and fastening
instrument 3010 according to various embodiments of the present
invention. The illustrated embodiment is an endoscopic instrument
and, in general, the embodiments of the instrument 3010 described
herein are endoscopic surgical cutting and fastening instruments.
It should be noted, however, that according to other embodiments of
the present invention, the instrument may be a non-endoscopic
surgical cutting and fastening instrument, such as a laparoscopic
instrument.
[0180] The surgical instrument 3010 depicted in FIGS. 38 and 39
comprises a handle 3012, a shaft 3014, and an articulating end
effector 3016 pivotally connected to the shaft 3014 at an
articulation pivot 3018. Correct placement and orientation of the
end effector 3016 may be facilitated by controls on the handle
3012, including (1) a rotation knob 3017 for rotating the closure
tube (described in more detail below in connection with FIGS.
41-42) at a free rotating joint 3019 of the shaft 3014 to thereby
rotate the end effector 3016 and (2) an articulation control 3020
to effect rotational articulation of the end effector 3016 about
the articulation pivot 3018. In the illustrated embodiment, the end
effector 3016 is configured to act as an endocutter for clamping,
severing and stapling tissue, although, in other embodiments,
different types of end effectors may be used, such as end effectors
for other types of surgical devices, such as graspers, cutters,
staplers, clip appliers, access devices, drug/gene therapy devices,
ultrasound, RF or laser devices, etc.
[0181] The handle 3012 of the instrument 3010 may include a closure
trigger 3022 and a firing trigger 3024 for actuating the end
effector 3016. It will be appreciated that instruments having end
effectors directed to different surgical tasks may have different
numbers or types of triggers or other suitable controls for
operating the end effector 3016. The end effector 3016 is shown
separated from the handle 3012 by a preferably elongate shaft 3014.
In one embodiment, a clinician or operator of the instrument 3010
may articulate the end effector 3016 relative to the shaft 3014 by
utilizing the articulation control 3020 as described in more detail
in U.S. patent application Ser. No. 11/329,020 entitled SURGICAL
INSTRUMENT HAVING AN ARTICULATING END EFFECTOR, now U.S. Pat. No.
7,670,334, which is incorporated herein by reference.
[0182] The end effector 3016 includes in this example, among other
things, a staple channel 3026 and a pivotally translatable clamping
member, such as an anvil 3028, which are maintained at a spacing
that assures effective stapling and severing of tissue clamped in
the end effector 3016. The handle 3012 includes a pistol grip 3030
towards which a closure trigger 3022 is pivotally drawn by the
clinician to cause clamping or closing of the anvil 3028 toward the
staple channel 3026 of the end effector 3016 to thereby clamp
tissue positioned between the anvil 3028 and the channel 3026. The
firing trigger 3024 is farther outboard of the closure trigger
3022. Once the closure trigger 3022 is locked in the closure
position as further described below, the firing trigger 3024 may
rotate slightly toward the pistol grip 3030 so that it can be
reached by the operator using one hand. The operator may then
pivotally draw the firing trigger 3024 toward the pistol grip 3030
to cause the stapling and severing of clamped tissue in the end
effector 3016. In other embodiments, different types of clamping
members besides the anvil 3028 may be used, such as, for example,
an opposing jaw, etc.
[0183] It will be appreciated that the terms "proximal" and
"distal" are used herein with reference to a clinician gripping the
handle 3012 of an instrument 3010. Thus, the end effector 3016 is
distal with respect to the more proximal handle 3012. It will be
further appreciated that, for convenience and clarity, spatial
terms such as "vertical" and "horizontal" are used herein with
respect to the drawings. However, surgical instruments are used in
many orientations and positions, and these terms are not intended
to be limiting and absolute.
[0184] The closure trigger 3022 may be actuated first. Once the
clinician is satisfied with the positioning of the end effector
3016, the clinician may draw back the closure trigger 3022 to its
fully closed, locked position proximate to the pistol grip 3030.
The firing trigger 3024 may then be actuated. The firing trigger
3024 returns to the open position (shown in FIGS. 38 and 39) when
the clinician removes pressure, as described more fully below. A
release button 3032 on the handle 3012, when depressed, may release
the locked closure trigger 3022. Various configurations for locking
and unlocking the closure trigger 3022 using the release button
3032 are described in U.S. patent application Ser. No. 11/343,573
entitled MOTOR-DRIVEN SURGICAL CUTTING AND FASTENING INSTRUMENT
WITH LOADING FORCE FEEDBACK, now U.S. Pat. No. 7,416,101, which is
incorporated herein by reference.
[0185] FIG. 40A is an exploded view of the end effector 3016
according to various embodiments, and FIG. 40B is a perspective
view of the cutting instrument of FIG. 40A. As shown in the
illustrated embodiment, the end effector 3016 may include, in
addition to the previously-mentioned channel 3026 and anvil 3028, a
cutting instrument 3034, a staple cartridge 3038 that is removably
seated (e.g., installed) in the channel 3026, a sled 3036 disposed
within the staple cartridge 3038, and a helical screw shaft
3040.
[0186] The anvil 3028 may be pivotably opened and closed at a pivot
point 3042 connected to the proximate end of the channel 3026. The
anvil 3028 may also include a tab 3044 at its proximate end that is
inserted into a component of the mechanical closure system
(described further below) to open and close the anvil 3028. When
the closure trigger 3022 is actuated, that is, drawn in by an
operator of the instrument 3010, the anvil 3028 may pivot about the
pivot point 3042 into the clamped or closed position. If clamping
of the end effector 3016 is satisfactory, the operator may actuate
the firing trigger 3024, which, as explained in more detail below,
causes the cutting instrument 3034 to travel longitudinally along
the channel 3026.
[0187] As shown, the cutting instrument 3034 includes upper guide
pins 3046 that enter an anvil slot 3048 in the anvil 3028 to verify
and assist in maintaining the anvil 3028 in a closed state during
staple formation and severing. Spacing between the channel 3026 and
anvil 3028 is further maintained by the cutting instrument 3034 by
having middle pins 3050 slide along the top surface of the channel
3026 while a bottom foot 3052 opposingly slides along the
undersurface of the channel 3026, guided by a longitudinal opening
3054 in the channel 3026. A distally presented cutting surface 3056
between the upper guide pins 3046 and middle pins 3050 severs
clamped tissue while distally-presented surface 3058 actuates the
staple cartridge 3038 by engaging and progressively driving the
sled 3036 through the staple cartridge 3038 from an unfired
position located at a proximal end of the staple cartridge 3038 to
a fired position located at a distal end of the staple cartridge
3038. When the sled 3036 is in the unfired position, the staple
cartridge 3038 is in an unfired, or unspent, state. When the sled
3036 is in the fired position, the staple cartridge 3038 is in a
fired, or spent, state. Actuation of the staple cartridge 3038
causes staple drivers 3060 to cam upwardly, driving staples 3062
out of upwardly open staple holes 3064 formed in the staple
cartridge 3038. The staples 3062 are subsequently formed against a
staple forming undersurface 66 of the anvil 3028. A staple
cartridge tray 3068 encompasses from the bottom the other
components of the staple cartridge 3038 to hold them in place. The
staple cartridge tray 3068 includes a rearwardly open slot 3070
that overlies the longitudinal opening 3054 in the channel 3026. A
lower surface of the staple cartridge 3038 and an upward surface of
the channel 3026 form a firing drive slot 3200 (FIG. 43) through
which the middle pins 3050 pass during distal and proximal movement
of the cutting instrument 3034. The sled 3036 may be an integral
component of the staple cartridge 3038 such that when the cutting
instrument 3034 retracts following the cutting operation, the sled
3036 does not retract. U.S. Pat. No. 6,978,921, entitled SURGICAL
STAPLING INSTRUMENT INCORPORATING AN E-BEAM FIRING MECHANISM, which
is incorporated herein by reference, provides more details about
such two-stroke cutting and fastening instruments.
[0188] It should be noted that although the embodiments of the
instrument 3010 described herein employ an end effector 3016 that
staples the severed tissue, in other embodiments different
techniques for fastening or sealing the severed tissue may be used.
For example, end effectors that use RF energy or adhesives to
fasten the severed tissue may also be used. U.S. Pat. No. 5,709,680
entitled ELECTROSURGICAL HEMOSTATIC DEVICE, and U.S. Pat. No.
5,688,270 entitled ELECTROSURGICAL HEMOSTATIC DEVICE WITH RECESSED
AND/OR OFFSET ELECTRODES, both of which are incorporated herein by
reference, disclose cutting instruments that uses RF energy to
fasten the severed tissue. U.S. patent application Ser. No.
11/267,811 entitled SURGICAL STAPLING INSTRUMENTS STRUCTURED FOR
DELIVERY OF MEDICAL AGENTS, now U.S. Pat. No. 7,673,783, and U.S.
patent application Ser. No. 11/267,383 entitled SURGICAL STAPLING
INSTRUMENTS STRUCTURED FOR PUMP-ASSISTED DELIVERY OF MEDICAL
AGENTS, now U.S. Pat. No. 7,607,557, both of which are also
incorporated herein by reference, disclose cutting instruments that
uses adhesives to fasten the severed tissue. Accordingly, although
the description herein refers to cutting/stapling operations and
the like, it should be recognized that this is an exemplary
embodiment and is not meant to be limiting. Other tissue-fastening
techniques may also be used.
[0189] FIGS. 41 and 42 are exploded views and FIG. 43 is a side
view of the end effector 3016 and shaft 3014 according to various
embodiments. As shown in the illustrated embodiment, the shaft 3014
may include a proximate closure tube 3072 and a distal closure tube
3074 pivotably linked by a pivot links 3076. The distal closure
tube 3074 includes an opening 3078 into which the tab 3044 on the
anvil 3028 is inserted in order to open and close the anvil 3028,
as further described below. Disposed inside the closure tubes 3072,
3074 may be a proximate spine tube 3079. Disposed inside the
proximate spine tube 3079 may be a main rotational (or proximate)
drive shaft 3080 that communicates with a secondary (or distal)
drive shaft 3082 via a bevel gear assembly 3084. The secondary
drive shaft 3082 is connected to a drive gear 3086 that engages a
proximate drive gear 3088 of the helical screw shaft 3040. The
vertical bevel gear 3084b may sit and pivot in an opening 3090 in
the distal end of the proximate spine tube 3079. A distal spine
tube 3092 may be used to enclose the secondary drive shaft 3082 and
the drive gears 3086, 3088. Collectively, the main drive shaft
3080, the secondary drive shaft 3082, and the articulation assembly
(e.g., the bevel gear assembly 3084a-c) are sometimes referred to
herein as the "main drive shaft assembly."
[0190] A bearing 3094, positioned at a distal end of the staple
channel 3026, receives the helical drive screw 3040, allowing the
helical drive screw 3040 to freely rotate with respect to the
channel 3026. The helical screw shaft 3040 may interface a threaded
opening (not shown) of the cutting instrument 3034 such that
rotation of the shaft 3040 causes the cutting instrument 3034 to
translate distally or proximately (depending on the direction of
the rotation) through the staple channel 3026. Accordingly, when
the main drive shaft 3080 is caused to rotate by actuation of the
firing trigger 3024 (as explained in further detail below), the
bevel gear assembly 3084a-c causes the secondary drive shaft 3082
to rotate, which in turn, because of the engagement of the drive
gears 3086, 3088, causes the helical screw shaft 3040 to rotate,
which causes the cutting instrument 3034 to travel longitudinally
along the channel 3026 to cut any tissue clamped within the end
effector 3016. The sled 3036 may be made of, for example, plastic,
and may have a sloped distal surface. As the sled 3036 traverses
the channel 3026, the sloped distal surface may cam the staple
drivers 3060 upward, which in turn push up or drive the staples
3062 in the staple cartridge 3038 through the clamped tissue and
against the staple forming undersurface 3066 of the anvil 3028,
thereby stapling the severed tissue. When the cutting instrument
3034 is retracted, the cutting instrument 3034 and the sled 3036
may become disengaged, thereby leaving the sled 3036 at the distal
end of the channel 3026.
[0191] FIGS. 44-47 illustrate an exemplary embodiment of a
motor-driven endocutter, and in particular the handle 3012 thereof,
that provides operator-feedback regarding the deployment and
loading force of the cutting instrument 3034 in the end effector
3016. In addition, the embodiment may use power provided by the
operator in retracting the firing trigger 3024 to power the device
(a so-called "power assist" mode). As shown in the illustrated
embodiment, the handle 3012 includes exterior lower side pieces
3096, 3098 and exterior upper side pieces 3100, 3102 that fit
together to form, in general, the exterior of the handle 3012. A
battery 3104 may be provided in the pistol grip portion 3030 of the
handle 3012. The battery 3104 may be constructed according to any
suitable construction or chemistry including, for example, a Li-ion
chemistry such as LiCoO.sub.2 or LiNiO.sub.2, a Nickel Metal
Hydride chemistry, etc. The battery 3104 powers a motor 3106
disposed in an upper portion of the pistol grip portion 3030 of the
handle 3012. According to various embodiments, the motor 3106 may
be a DC brushed driving motor having a maximum rotation of
approximately 5000 to 100,000 RPM. The motor 3106 may drive a
90-degree bevel gear assembly 3108 comprising a first bevel gear
3110 and a second bevel gear 3112. The bevel gear assembly 3108 may
drive a planetary gear assembly 3114. The planetary gear assembly
3114 may include a pinion gear 3116 connected to a drive shaft
3118. The pinion gear 3116 may drive a mating ring gear 3120 that
drives a helical gear drum 3122 via a drive shaft 3124. A ring 3126
may be threaded on the helical gear drum 3122. Thus, when the motor
3106 rotates, the ring 3126 is caused to travel along the helical
gear drum 3122 by means of the interposed bevel gear assembly 3108,
planetary gear assembly 3114 and ring gear 3120.
[0192] The handle 3012 may also include a run motor sensor 3128 in
communication with the firing trigger 3024 to detect when the
firing trigger 3024 has been drawn in (or "closed") toward the
pistol grip portion 3030 of the handle 3012 by the operator to
thereby actuate the cutting/stapling operation by the end effector
3016. The sensor 3128 may be a proportional sensor such as, for
example, a rheostat or variable resistor. When the firing trigger
3024 is drawn in, the sensor 3128 detects the movement, and sends
an electrical signal indicative of the voltage (or power) to be
supplied to the motor 3106. When the sensor 3128 is a variable
resistor or the like, the rotation of the motor 3106 may be
generally proportional to the amount of movement of the firing
trigger 3024. That is, if the operator only draws or closes the
firing trigger 3024 in a little bit, the rotation of the motor 3106
is relatively low. When the firing trigger 3024 is fully drawn in
(or in the fully closed position), the rotation of the motor 3106
is at its maximum. In other words, the harder the operator pulls on
the firing trigger 3024, the more voltage is applied to the motor
3106, causing a greater rate of rotation. In another embodiment,
for example, the control unit (described further below) may output
a PWM control signal to the motor 3106 based on the input from the
sensor 3128 in order to control the motor 3106.
[0193] The handle 3012 may include a middle handle piece 3130
adjacent to the upper portion of the firing trigger 3024. The
handle 3012 also may comprise a bias spring 3132 connected between
posts on the middle handle piece 3130 and the firing trigger 3024.
The bias spring 3132 may bias the firing trigger 3024 to its fully
open position. In that way, when the operator releases the firing
trigger 3024, the bias spring 3132 will pull the firing trigger
3024 to its open position, thereby removing actuation of the sensor
3128, thereby stopping rotation of the motor 3106. Moreover, by
virtue of the bias spring 3132, any time an operator closes the
firing trigger 3024, the operator will experience resistance to the
closing operation, thereby providing the operator with feedback as
to the amount of rotation exerted by the motor 3106. Further, the
operator could stop retracting the firing trigger 3024 to thereby
remove force from the sensor 3128, to thereby stop the motor 3106.
As such, the operator may stop the deployment of the end effector
3016, thereby providing a measure of control of the
cutting/fastening operation to the operator.
[0194] The distal end of the helical gear drum 3122 includes a
distal drive shaft 3134 that drives a ring gear 3136, which mates
with a pinion gear 3138. The pinion gear 3138 is connected to the
main drive shaft 3080 of the main drive shaft assembly. In that
way, rotation of the motor 3106 causes the main drive shaft
assembly to rotate, which causes actuation of the end effector
3016, as described above.
[0195] The ring 3126 threaded on the helical gear drum 3122 may
include a post 3140 that is disposed within a slot 3142 of a
slotted arm 3144. The slotted arm 3144 has an opening 3146 its
opposite end 3148 that receives a pivot pin 3150 that is connected
between the handle exterior side pieces 3096, 3098. The pivot pin
3150 is also disposed through an opening 3152 in the firing trigger
3024 and an opening 3154 in the middle handle piece 3130.
[0196] In addition, the handle 3012 may include a reverse motor (or
end-of-stroke) sensor 3156 and a stop motor (or
beginning-of-stroke) sensor 3158. In various embodiments, the
reverse motor sensor 3156 may be a normally-open limit switch
located at the distal end of the helical gear drum 3122 such that
the ring 3126 threaded on the helical gear drum 3122 contacts and
closes the reverse motor sensor 3156 when the ring 3126 reaches the
distal end of the helical gear drum 3122. The reverse motor sensor
3156, when closed, sends a signal to the control unit which sends a
signal to the motor 3106 to reverse its rotation direction, thereby
withdrawing the cutting instrument of the end effector 3016
following the cutting operation.
[0197] The stop motor sensor 3158 may be, for example, a
normally-closed limit switch. In various embodiments, it may be
located at the proximate end of the helical gear drum 3122 so that
the ring 3126 opens the switch 3158 when the ring 3126 reaches the
proximate end of the helical gear drum 3122.
[0198] In operation, when an operator of the instrument 3010 pulls
back the firing trigger 3024, the sensor 3128 detects the
deployment of the firing trigger 3024 and sends a signal to the
control unit which sends a signal to the motor 3106 to cause
forward rotation of the motor 3106 at, for example, a rate
proportional to how hard the operator pulls back the firing trigger
3024. The forward rotation of the motor 3106 in turn causes the
ring gear 3120 at the distal end of the planetary gear assembly
3114 to rotate, thereby causing the helical gear drum 3122 to
rotate, causing the ring 3126 threaded on the helical gear drum
3122 to travel distally along the helical gear drum 3122. The
rotation of the helical gear drum 3122 also drives the main drive
shaft assembly as described above, which in turn causes deployment
of the cutting instrument 3034 in the end effector 3016. That is,
the cutting instrument 3034 and sled 3036 are caused to traverse
the channel 3026 longitudinally, thereby cutting tissue clamped in
the end effector 3016. Also, the stapling operation of the end
effector 3016 is caused to happen in embodiments where a
stapling-type end effector is used.
[0199] By the time the cutting/stapling operation of the end
effector 3016 is complete, the ring 3126 on the helical gear drum
3122 will have reached the distal end of the helical gear drum
3122, thereby causing the reverse motor sensor 3156 to be actuated,
which sends a signal to the control unit which sends a signal to
the motor 3106 to cause the motor 3106 to reverse its rotation.
This in turn causes the cutting instrument 3034 to retract, and
also causes the ring 3126 on the helical gear drum 3122 to move
back to the proximate end of the helical gear drum 3122.
[0200] The middle handle piece 3130 includes a backside shoulder
3160 that engages the slotted arm 3144 as best shown in FIGS. 45
and 46. The middle handle piece 3130 also has a forward motion stop
3162 that engages the firing trigger 3024. The movement of the
slotted arm 3144 is controlled, as explained above, by rotation of
the motor 3106. When the slotted arm 3144 rotates CCW as the ring
3126 travels from the proximate end of the helical gear drum 3122
to the distal end, the middle handle piece 3130 will be free to
rotate CCW. Thus, as the operator draws in the firing trigger 3024,
the firing trigger 3024 will engage the forward motion stop 3162 of
the middle handle piece 3130, causing the middle handle piece 3130
to rotate CCW. Due to the backside shoulder 3160 engaging the
slotted arm 3144, however, the middle handle piece 3130 will only
be able to rotate CCW as far as the slotted arm 3144 permits. In
that way, if the motor 3106 should stop rotating for some reason,
the slotted arm 3144 will stop rotating, and the operator will not
be able to further draw in the firing trigger 3024 because the
middle handle piece 3130 will not be free to rotate CCW due to the
slotted arm 3144.
[0201] FIGS. 48 and 49 illustrate two states of a variable sensor
that may be used as the run motor sensor 3128 according to various
embodiments of the present invention. The sensor 3128 may include a
face portion 3164, a first electrode (A) 3166, a second electrode
(B) 3168, and a compressible dielectric material 3170 (e.g., EAP)
between the electrodes 3166, 3168. The sensor 3128 may be
positioned such that the face portion 3164 contacts the firing
trigger 3024 when retracted. Accordingly, when the firing trigger
3024 is retracted, the dielectric material 3170 is compressed, as
shown in FIG. 49, such that the electrodes 3166, 3168 are closer
together. Since the distance "b" between the electrodes 3166, 3168
is directly related to the impedance between the electrodes 3166,
3168, the greater the distance the more impedance, and the closer
the distance the less impedance. In that way, the amount that the
dielectric material 3170 is compressed due to retraction of the
firing trigger 3024 (denoted as force "F" in FIG. 49) is
proportional to the impedance between the electrodes 3166, 3168.
This impedance provided by the sensor 3128 may be used with
suitable signal conditioning circuitry to proportionally control
the speed of the motor 3106, for example.
[0202] Components of an exemplary closure system for closing (or
clamping) the anvil 3028 of the end effector 3016 by retracting the
closure trigger 3022 are also shown in FIGS. 44-47. In the
illustrated embodiment, the closure system includes a yoke 3172
connected to the closure trigger 3022 by a pin 3174 that is
inserted through aligned openings in both the closure trigger 3022
and the yoke 3172. A pivot pin 3176, about which the closure
trigger 3022 pivots, is inserted through another opening in the
closure trigger 3022 which is offset from where the pin 3174 is
inserted through the closure trigger 3022. Thus, retraction of the
closure trigger 3022 causes the upper part of the closure trigger
3022, to which the yoke 3172 is attached via the pin 3174, to
rotate CCW. The distal end of the yoke 3172 is connected, via a pin
3178, to a first closure bracket 3180. The first closure bracket
3180 connects to a second closure bracket 3182. Collectively, the
closure brackets 3180, 3182 define an opening in which the proximal
end of the proximate closure tube 3072 (see FIG. 41) is seated and
held such that longitudinal movement of the closure brackets 3180,
3182 causes longitudinal motion by the proximate closure tube 3072.
The instrument 3010 also includes a closure rod 3184 disposed
inside the proximate closure tube 3072. The closure rod 3184 may
include a window 3186 into which a post 3188 on one of the handle
exterior pieces, such as exterior lower side piece 3096 in the
illustrated embodiment, is disposed to fixedly connect the closure
rod 3184 to the handle 3012. In that way, the proximate closure
tube 3072 is capable of moving longitudinally relative to the
closure rod 3184. The closure rod 3184 may also include a distal
collar 3190 that fits into a cavity 3192 in proximate spine tube
3079 and is retained therein by a cap 3194 (see FIG. 41).
[0203] In operation, when the yoke 3172 rotates due to retraction
of the closure trigger 3022, the closure brackets 3180, 3182 cause
the proximate closure tube 3072 to move distally (i.e., away from
the handle 3012 of the instrument 3010), which causes the distal
closure tube 3074 to move distally, which causes the anvil 3028 to
rotate about the pivot point 3042 into the clamped or closed
position. When the closure trigger 3022 is unlocked from the locked
position, the proximate closure tube 3072 is caused to slide
proximally, which causes the distal closure tube 3074 to slide
proximally, which, by virtue of the tab 3044 being inserted in the
opening 3078 of the distal closure tube 3074, causes the anvil 3028
to pivot about the pivot point 3042 into the open or unclamped
position. In that way, by retracting and locking the closure
trigger 3022, an operator may clamp tissue between the anvil 3028
and channel 3026, and may unclamp the tissue following the
cutting/stapling operation by unlocking the closure trigger 3022
from the locked position.
[0204] The control unit (described further below) may receive the
outputs from end-of-stroke and beginning-of-stroke sensors 3156,
3158 and the run-motor sensor 3128, and may control the motor 3106
based on the inputs. For example, when an operator initially pulls
the firing trigger 3024 after locking the closure trigger 3022, the
run-motor sensor 3128 is actuated. If the control unit determines
that an unspent staple cartridge 3038 is present in the end
effector 3016, as described further below, the control unit may
output a control signal to the motor 3106 to cause the motor 3106
to rotate in the forward direction. When the end effector 3016
reaches the end of its stroke, the reverse motor sensor 3156 will
be activated. The control unit may receive this output from the
reverse motor sensor 3156 and cause the motor 3106 to reverse its
rotational direction. When the cutting instrument 3034 is fully
retracted, the stop motor sensor switch 3158 is activated, causing
the control unit to stop the motor 3106.
[0205] According to various embodiments, the instrument 3010 may
include a transponder in the end effector 3016. The transponder may
generally be any device suitable for transmitting a wireless
signal(s) indicating one or more conditions of the end effector
3016. In certain embodiments, for example, wireless signals may be
transmitted by the transponder to the control unit responsive to
wireless signals received from the control unit. In such
embodiments, the wireless signals transmitted by the control unit
and the transponder are referred to as "interrogation" and "reply"
signals, respectively. The transponder may be in communication with
one or more types of sensors (e.g., position sensors, displacement
sensors, pressure/load sensors, proximity sensors, etc.) located in
the end effector 3016 for transducing various end effector
conditions such as, for example, a state of the staple cartridge
3038 (e.g., fired or unfired) and the respective positions of the
anvil 3028 (e.g., open or closed) and the sled 3036 (e.g., proximal
or distal). According to various embodiments and as discussed
below, the transponder may be a passive device such that its
operating power is derived from wireless signals (e.g.,
interrogation signals). In other embodiments, the transponder may
be an active device powered by a self-contained power source (e.g.,
a battery) disposed within the end effector 3016. The transponder
and the control circuit may be configured to communicate using any
suitable type of wireless signal. According to various embodiments
and as discussed below, for example, the transponder and the
control circuit may transmit and receive wireless signals using
magnetic fields generated by inductive effects. It will be
appreciated that the transponder and the control circuit may
instead transmit and receive wireless signals using electromagnetic
fields (e.g., RF signals, optical signals), or using electric
fields generated by capacitive effects, for example. It will
further be appreciated that the end effector 3016 may include
additional transponders, with each transponder having one more
dedicated sensors for inputting data thereto.
[0206] FIG. 50 illustrates a block diagram of the control unit 3196
according to various embodiments. As shown, the control unit 3196
may comprise a processor 3198 and one or more memory units 3200.
The control unit 3196 may be powered by the battery 3104 or other
suitable power source contained within the instrument 3010. In
certain embodiments, the control unit 3196 may further comprise an
inductive element 3202 (e.g., a coil or antenna) to transmit and
receive wireless signals (e.g., interrogation and reply signals)
from the transponder via magnetic fields. Signals received by the
inductive element 3202 may be demodulated by a demodulator 3204 and
decoded by a decoder 3206. By executing instruction code stored in
the memory 3200, the processor 3198 may control various components
of the instrument 3010, such as the motor 3106 and a user display
(not shown), based on inputs of the end effector sensors (as
indicated by the decoded signals) and inputs received from other
various sensor(s) (such as the run-motor sensor 3128, the
end-of-stroke and beginning-of-stroke sensors 3156, 3158, for
example).
[0207] Wireless signals output by the control unit 3196 may be in
the form of alternating magnetic fields emitted by the inductive
element 3202. The control unit 3196 may comprise an encoder 3208
for encoding data to be transmitted to the transponder and a
modulator 3210 for modulating the magnetic field based on the
encoded data using a suitable modulation scheme. The control unit
3196 may communicate with the transponder using any suitable
wireless communication protocol and any suitable frequency (e.g.,
an ISM band or other RF band). Also, the control unit 3196 may
transmit signals at a different frequency range than the frequency
range of the reply signals received from the transponder.
Additionally, although only one antenna (inductive element 3202) is
shown in FIG. 50, in other embodiments the control unit 3196 may
have separate receiving and transmitting antennas.
[0208] According to various embodiments, the control unit 3196 may
comprise a microcontroller, a microprocessor, a field programmable
gate array (FPGA), one or more other types of integrated circuits
(e.g., RF receivers and PWM controllers), and/or discrete passive
components. The control unit 3196 may also be embodied as
system-on-chip (SoC) or a system-in-package (SIP), for example.
[0209] As shown in FIG. 51, the control unit 3196 may be housed in
the handle 3012 of the instrument 3010 and the transponder 3212 may
be located in the end effector 3016. To transmit signals to the
transponder 3212 and receive signals therefrom, the inductive
element 3202 of the control unit 3196 may be inductively coupled to
a secondary inductive element (e.g., a coil) 3214 positioned in the
shaft 3014 distally from the rotation joint 3019. The secondary
inductive element 3214 is preferably electrically insulated from
the conductive shaft 3014.
[0210] The secondary inductive element 3214 may be connected by an
electrically conductive, insulated wire 3216 to a distal inductive
element (e.g., a coil) 3218 located near the end effector 3016, and
preferably distally located relative to the articulation pivot
3018. The wire 3216 may be made of an electrically conductive
polymer and/or metal (e.g., copper) and may be sufficiently
flexible so that it could pass though the articulation pivot 3018
and not be damaged by articulation. The distal inductive element
3218 may be inductively coupled to the transponder 3212 in, for
example, the staple cartridge 3038 of the end effector 3016. The
transponder 3212, as described in more detail below, may include an
antenna (or coil) for inductively coupling to the distal coil 3218,
as well as associated circuitry for transmitting and receiving
wireless signals.
[0211] In certain embodiments, the transponder 3212 may be
passively powered by magnetic fields emitted by the distal
inductive element 3218. Once sufficiently powered, the transponder
3212 may transmit and/or receive data (e.g., by modulating the
magnetic fields) to the control unit 3196 in the handle 3012 via
(i) the inductive coupling between the transponder 3212 and the
distal inductive element 3218, (ii) the wire 3216, and (iii) the
inductive coupling between the secondary inductive element 3214 and
the control unit 3196. The control unit 3196 may thus communicate
with the transponder 3212 in the end effector 3016 without a
hardwired connection through complex mechanical joints like the
rotating joint 3019 and/or without a hardwired connection from the
shaft 3014 to the end effector 3016, places where it may be
difficult to maintain such connections. In addition, because the
distances between the inductive elements (e.g., the spacing between
(i) the transponder 3212 and the distal inductive element 3218, and
(ii) the secondary inductive element 3214 and the control unit
3196) are fixed and known, the couplings could be optimized for
inductive energy transfer. Also, the distances could be relatively
short so that relatively low power signals could be used to thereby
minimize interference with other systems in the use environment of
the instrument 3010.
[0212] In the embodiment of FIG. 51, the inductive element 3202 of
the control unit 3196 is located relatively near to the control
unit 3196. According to other embodiments, as shown in FIG. 52, the
inductive element 3202 of the control unit 3196 may be positioned
closer to the rotating joint 3019 to that it is closer to the
secondary inductive element 3214, thereby reducing the distance of
the inductive coupling in such an embodiment. Alternatively, the
control unit 3196 (and hence the inductive element 3202) could be
positioned closer to the secondary inductive element 3214 to reduce
the spacing.
[0213] In other embodiments, more or fewer than two inductive
couplings may be used. For example, in some embodiments, the
surgical instrument 3010 may use a single inductive coupling
between the control unit 3196 in the handle 3012 and the
transponder 3212 in the end effector 3016, thereby eliminating the
inductive elements 3214, 3218 and the wire 3216. Of course, in such
an embodiment, stronger signals may be required due to the greater
distance between the control unit 3196 in the handle 3012 and the
transponder 3212 in the end effector 3016. Also, more than two
inductive couplings could be used. For example, if the surgical
instrument 3010 had numerous complex mechanical joints where it
would be difficult to maintain a hardwired connection, inductive
couplings could be used to span each such joint. For example,
inductive couplings could be used on both sides of the rotary joint
3019 and both sides of the articulation pivot 3018, with an
inductive element 3220 on the distal side of the rotary joint 3019
connected by the wire 3216 to the inductive element 3218 of the
proximate side of the articulation pivot, and a wire 3222
connecting inductive elements 3224, 3226 on the distal side of the
articulation pivot 3018 as shown in FIG. 53. In this embodiment,
the inductive element 3226 may communicate with the transponder
3212.
[0214] In the above-described embodiments, each of the inductive
elements 3202, 3214, 3218, 3224, 3226 may or may not include
ferrite cores. Additionally, the inductive elements 3214, 3218,
3224, 3226 are also preferably insulated from the electrically
conductive outer shaft (or frame) of the instrument 3010 (e.g., the
closure tubes 3072, 3074), and the wires 3216, 3222 are also
preferably insulated from the outer shaft 3014.
[0215] FIG. 54 is a bottom view of a portion of the staple
cartridge 3038 including the transponder 3212 according to various
embodiments. As shown, the transponder 3212 may be held or embedded
in the staple cartridge 3038 at its distal end using a suitable
bonding material, such as epoxy.
[0216] FIG. 55 illustrates a circuit diagram of the transponder
3212 according to various embodiments. As shown, the transponder
3212 may include a resonant circuit 3249 comprising an inductive
element 3250 (e.g., a coil or antenna) and a capacitor 3252. The
transponder 3212 may further include a microchip 3254 coupled to
the resonant circuit 3249. In certain embodiments, the microchip
3254 may be, for example, an RFID device containing circuitry for
enabling communication with the control unit 3196 via the inductive
element 3250 of the resonant circuit 3249. The microchip 3254 may
include at least one data input for receiving data in the form of
discrete or analog signals from the sensors 3235 disposed in the
end effector 3016. As discussed above, the sensors 3235 may
include, for example, position sensors, displacement sensors,
pressure/load sensors, proximity sensors for sensing various end
effector conditions. The microchip 3254 also may include one or
more dynamic memory devices 3255 (e.g., flash memory devices) for
storing data transmitted from, for example, the control unit 3196.
The microchip 3254 may further include one or more non-dynamic
memory devices 3257 (e.g., write-once memory devices) for storing
static data, such as, for example, a staple cartridge
identification number, manufacturer information, and information
pertaining to physical characteristics of the staple cartridge
3038.
[0217] In response to alternating magnetic fields emitted by the
distal inductive element 3218, the resonant circuit 3249 of the
transponder 3212 is caused to resonate, thereby causing an
alternating input voltage to be applied to the microchip 3254. The
resonant circuit 3249 may have a resonant frequency given by
f r = 1 2 .pi. L 1 C 1 , ##EQU00001##
where L.sub.1 is the inductance value of the inductive element 3250
and C.sub.1 is the capacitance value of the capacitor 3252. The
values of L.sub.1 and C.sub.1 may be selected such that the
resonant frequency of the circuit 3249 is equal or nearly equal to
the frequency of magnetic field transmitted by the distal inductive
element 3218. The circuitry of the microchip 3254 may include a
rectifying circuitry (not shown) for rectifying and conditioning
the alternating input voltage to provide a DC voltage sufficient to
power the microchip 3254. Once powered, the microchip 3254 may
selectively load the inductive element 3250 based on data received
from the sensors 3235 and the data stored in the memory devices
3255, 3257, thus modulating the magnetic fields coupling the distal
inductive element 3218 and the inductive element 3250. The
modulation of the magnetic field modulates the voltage across the
distal inductive element 3218, which in turn modulates the voltage
across the inductive element 3202 of the control unit 3196. The
control unit 3196 may demodulate and decode the voltage signal
across the inductive element 3202 to extract data communicated by
the microchip 3254. The control unit 3196 may process the data to
verify, among other things, that the staple cartridge 3038 is
compatible with the instrument 3010 and that end effector
conditions are suitable for conducting a firing operation.
Subsequent to verification of the data, the control unit 3196 may
enable a firing operation.
[0218] According to various embodiments, the resonant circuit 3249
may further include a fuse 3256 connected in series with the
inductive element 3250. When the fuse 3256 is closed (e.g.,
conductive), the inductive element 3250 is electrically coupled to
the resonant circuit 3249, thus enabling the transponder 3212 to
function as described above in response to an alternating magnetic
field emitted by the distal inductive element 3218. The closed
state of the fuse 3256 thus corresponds to an enabled state of the
transponder 3212. When the fuse 3256 is opened (e.g.,
non-conductive), the inductive element 3250 is electrically
disconnected from the resonant circuit 3249, thus preventing the
resonant circuit 3249 from generating the voltage necessary to
operate the microchip 3254. The open state of the fuse 3256 thus
corresponds to a disabled state of the transponder 3212. The
placement of the fuse 3256 in FIG. 55 is shown by way of example
only, and it will be appreciated that the fuse 3256 may be
connected in any manner such that the transponder 3212 is disabled
when the fuse 3256 is opened.
[0219] According to various embodiments, the fuse 3256 may be
actuated (e.g., transitioned from closed to opened) substantially
simultaneously with a firing operation of the instrument 3010. For
example, the fuse 3256 may be actuated immediately before, during,
or immediately after a firing operation. Actuation of the fuse 3256
thus transitions the transponder 3212 from the enabled state to the
disabled state. Accordingly, if an attempt is made to reuse the
staple cartridge 3038, the transponder 3212 will be unable to
communicate data in response to a wireless signal transmitted by
the distal inductive element 3218. Based upon the absence of this
data, the control unit 3196 may determine that the transponder 3212
is in a disabled state indicative of the fired state of the staple
cartridge 3038 and prevent a firing operation from being enabled.
Thus, actuation of the fuse 3256 prevents reuse of a staple
cartridge 3038 when the staple cartridge 3038 is in the fired
state.
[0220] In certain embodiments, the fuse 3256 may be a
mechanically-actuated fuse that is opened in response to movement
of the cutting instrument 3034 when actuated, for example. As shown
in FIG. 56, for example, the fuse 3256 may include a section of
wire extending transversely across a longitudinal slot 3258 of the
staple cartridge 3038 through which the cutting instrument 3034
passes during a firing operation. When the instrument 3010 is
fired, the distal movement of the cutting instrument 3034 severs
the fuse 3256, thus transitioning the transponder 3212 to the
disabled state so that it cannot be reused.
[0221] According to other embodiments, the fuse 3256 may be an
electrically-actuated fuse. For example, subsequent to receiving
data from the transponder 3212 and verifying that the end effector
3016 is in a condition to be fired, the control unit 3196 may
transmit a wireless signal to the transponder 3212 such that the
resulting current flow through fuse 3256 is sufficient to cause the
fuse 3256 to open. It will be appreciated that the strength of the
wireless signal needed to open the fuse 3256 may be different in
amplitude, frequency, and duration than that used to communicate
with the transponder 3212. Additionally, it will be appreciated
that other electrically-actuated components may be used instead of
an electrically-actuated fuse to disable the transponder 3212. For
example, the control unit 3196 may transmit a wireless signal to
the transponder 3212 such that resulting voltage developed across
the resonant circuit 3256 sufficiently exceeds the voltage rating
of the capacitor 3252 and/or circuitry of the microchip 3254 to
cause their destruction.
[0222] As an alternative to using an electrically-actuated fuse,
the fuse 3256 may instead be a thermally-actuated fuse (e.g., a
thermal cutoff fuse) that is caused to open in response to heat
generated by the flow of excessive current therethrough.
[0223] In certain cases, it may be desirable to communicate with
the transponder 3212 when the staple cartridge 3038 is in the fired
state. In such cases, it is not possible to entirely disable the
transponder 3212 as described in the embodiments above. FIG. 57
illustrates a circuit diagram of the transponder 3212 according to
various embodiments for enabling wireless communication with the
control unit 3196 when the staple cartridge 3038 is in the fired
state. As shown, the resonant circuit 3249 of the transponder 3212
may include a second capacitor 3260 in parallel with the capacitor
3252. The fuse 3256 may be connected in series with the second
capacitor 3260 such that the resonant frequency of the resonant
circuit 3249 is determined by the open/closed state of the fuse
3256. In particular, when the fuse 3256 is closed, the resonant
frequency is given by
f r = 1 2 .pi. L 1 ( C 1 + C 2 ) , ##EQU00002##
where C.sub.2 is we capacitance value of the second capacitor 3260.
The closed state of the fuse 3256 thus corresponds to a first
resonant state of the transponder 3212. When the fuse 3256 is
opened, the resonant frequency is given by
f r = 1 2 .pi. L 1 C 1 . ##EQU00003##
me open state or me ruse 3256 thus corresponds to a second resonant
state of the transponder 3212. As described in the above
embodiments, the fuse 3256 may be mechanically, electrically or
thermally actuated substantially simultaneously with a firing
operation. The control unit 3196 may be configured to determine the
resonant state of the transponder 3212 (and thus the unfired/fired
state of the staple cartridge 3038) by discriminating between the
two resonant frequencies. Advantageously, because the resonant
circuit 3256 (and thus the microchip 3254) continue to operate
after the fuse 3256 is opened, the control unit 3196 may continue
to receive data from the transponder 3212. It will be appreciated
that the placement of the fuse 3256 and use of the second capacitor
3260 to alter the resonant frequency is provided by way of example
only. In other embodiments, for example, the fuse 3256 may be
connected such that the inductive value of the inductive element
3250 is changed when the fuse 3256 is opened (e.g., by connecting
the fuse 3256 such that a portion of the inductive element 3250 is
short-circuited when the fuse 3256 is closed).
[0224] According to various embodiments, a switch may be used as an
alternative to the fuse 3256 for effecting the transition between
transponder states. For example, as shown in FIG. 58, the staple
cartridge tray 3068 of the staple cartridge 3038 may include a
switch 3262 (e.g., a normally-open limit switch) located at its
proximal end. The switch 3262 may be mounted such that when the
sled 3036 is present in the unfired position, the sled 3036
maintains the switch 3262 in a closed (e.g., conductive) state.
When the sled 3036 is driven from the unfired position to the fired
position during a firing operation, the switch 3262 transitions to
an open (e.g., non-conductive state), thus effecting a transition
in the state of the transponder 3212 as described above. It will be
appreciated that in other embodiments the switch 3262 may be a
normally-closed switch mounted at the distal end of the staple
cartridge tray 3068 such that the switch 3262 is caused to open
when the sled 3036 is present in the fired position. It will
further be appreciated that the switch 3262 may be located at the
proximal or distal ends of the staple cartridge 3038 and mounted
such that it may be suitably actuated by the sled 3036 when present
in the unfired and fired positions, respectively.
[0225] As an alternative to connecting the mechanically-actuated
fuse 3256 or the switch 3262 to disable/alter the resonant circuit
3249, these components may instead be connected to data inputs of
the microchip 3254. In this way, the open/closed states of the
mechanically-actuated fuse 3256 or the switch 3262 may be
transmitted to the control unit 3196 in the same manner as the data
corresponding to other end effector conditions.
[0226] As an alternative to the fuse 3256 and the switch 3262,
embodiments of the present invention may instead utilize alterable
data values in a dynamic memory device 3255 of the transponder
3212. For example, the dynamic memory device 3255 may store a first
data value (e.g., a data bit having a value of 1) corresponding to
a first data state of the transponder 3212. The first data value
may be written to the dynamic memory device 3255 during the
manufacture of the staple cartridge 3038, for example. The first
data state may thus be indicative of the unfired state of the
staple cartridge 3038. Based on a determination of the first data
state of the transponder 3212, the control unit 3196 may enable
operation of the instrument 3010 if the end effector conditions are
otherwise suitable for conducting a firing operation. Substantially
simultaneously with the firing operation, the control unit 3196 may
transmit a wireless signal to the transponder 3212 containing a
second data value (e.g., a data bit having a value of 0). The
second data value may be stored to the dynamic memory device 3255
such that the first data value is overwritten, thus transitioning
the transponder 3212 from the first data state to a second data
state. The second data state may thus be indicative of the fired
state of the staple cartridge 3038. If an attempt is made to reuse
the staple cartridge 3038, the control unit 3196 may determine that
the transponder 3212 is in the second data state and prevent a
firing operation from being enabled.
[0227] Although the transponders 3212 in the above-described
embodiments includes a microchip 3254 for wirelessly communicating
data stored in memory devices 3235, 3237 and data input from the
sensors 3235, in other embodiments the transponder may not include
a microchip 3254. For example, FIG. 59 illustrates a "chipless"
transponder 3264 in the form of a resonant circuit having
components similar to those of the resonant circuit 3249, such as
an inductive element 3250, a capacitor 3252, and a fuse 3256.
Additionally, the transponder 3264 may include one or more sensors
3235 connected in series with the components 3250, 3252, 3256. In
certain embodiments and as shown, each sensor 3235 may be a limit
switch (e.g., a normally open or a normally closed limit switch)
mounted in the end effector 3016 for sensing a corresponding end
effector condition (e.g., a position of the anvil 3028, a position
of the sled 3036, etc.). In such embodiments, each limit switch
3235 may be in a closed (e.g., conductive) state when its sensed
condition is compatible with a firing operation, thus establishing
electrical continuity through the resonant circuit.
[0228] When each switch 3235 and the fuse 3256 is in the closed
state, the resonant circuit will be caused to resonate at a
frequency f.sub.r responsive to a magnetic field emitted by the
distal inductive element 3218. The closed states of the fuse 3256
and the switches 3235 thus correspond to an enabled state of the
transponder 3264 that is indicative of, among other things, the
unfired state of the staple cartridge 3038. The control unit 3196
may sense the resonance (e.g., by sensing magnetic field loading
caused by the resonant circuit) to determine the enabled state, at
which time the control unit 3196 may enable operation of the
instrument 3010. Substantially simultaneously with the actuation of
the cutting instrument 3034, the fuse 3256 may be mechanically,
electronically or thermally actuated as described above, thus
transitioning the transponder 3264 to a disabled state indicative
of the fired state of the staple cartridge 3038. If a subsequent
firing operation is attempted without replacing the staple
cartridge 3038, the control unit 3196 may determine the disabled
state based on the absence of a sensed resonance in response to an
emitted magnetic field, in which case the control unit 3196
prevents the firing operation from being performed.
[0229] FIG. 60 illustrates another embodiment of a chipless
transponder 3264 in the form of a resonant circuit including an
inductive element 3250, a first capacitor 3252, a second capacitor
3260, and a fuse 3256 connected in series with the second capacitor
3260. The fuse 3256 may be mechanically, electronically or
thermally actuated substantially simultaneously with a firing
operation, as in above-described embodiments. The transponder 3264
may additionally include one or more sensors 3235 (e.g., limit
switches) connected in series with a third capacitor 3266 of the
resonant circuit. Accordingly, when each switch 3235 and the fuse
3256 are in the closed state, the resonant circuit will be caused
to resonate at a frequency
f r 1 = 1 2 .pi. L 1 ( C 1 + C 2 + C 3 ) ##EQU00004##
responsive to a magnetic field emitted by the distal inductive
element 3218. When one of the switches 3235 is opened and the fuse
3256 is closed, the resonant frequency will be
f r 2 = 1 2 .pi. L 1 ( C 1 + C 2 ) , ##EQU00005##
and when each of the switches 3235 is closed and the fuse 3256 is
opened, the resonant frequency will be
f r 3 = 1 2 .pi. L 1 ( C 1 + C 3 ) . ##EQU00006##
When the switches 3235 and the fuse 3256 are opened, the resonant
frequency will be
f r 4 = 1 2 .pi. L 1 C 1 . ##EQU00007##
The closed states of the fuse 3256 and the switches 3235 correspond
to a first resonant state (e.g., resonant frequency f.sub.r1) of
the transponder 3264, and the open state of the fuse 3256
corresponds to a second resonant state (e.g., either of resonant
frequencies f.sub.r3 or f.sub.r4). The capacitance values C.sub.1,
C.sub.2 and C.sub.3 may be selected such that the resonant
frequencies f.sub.r1, f.sub.r2, f.sub.r3 and f.sub.r4 are
different. The control unit 3196 may be configured to discriminate
between resonant frequencies to determine the first or second state
of the transponder 3266 (and thus the unfired or fired state of the
staple cartridge 3038), and to enable or prevent operation of the
instrument 3010 accordingly. The control unit 3196 may further be
configured to determine a third state of the transponder 3264
corresponding the closed state of the fuse 3256 and an open state
of any of the switches 3235. In this case, the control unit 3196
may operate to prevent a firing operation until the end effector
condition(s) causing the open switch(es) 3235 is resolved.
[0230] FIG. 61 is a flow diagram of a method of preventing reuse of
a staple cartridge in surgical instrument that may be performed in
conjunction with embodiments of the instrument 3010 described
above. At step 3300, a first wireless signal is transmitted to the
transponder 3212, 3264 and at step 3305 a second wireless signal is
received from the transponder 3212, 3264 such that one of a first
electronic state and a second electronic state of the transponder
3212, 3264 may be determined based on the second wireless signal.
In certain embodiments and as explained above, the wireless signals
may be magnetic signals generated by inductive effects, although
electric fields and electromagnetic fields may alternatively be
employed. States of the transponder 3212, 3264 are indicative of
states of the staple cartridge 3038. In certain embodiments, for
example, the first and second transponder states may indicate the
unfired and fired states of the staple cartridge 3038,
respectively.
[0231] At step 3310, if the first electronic state (indicative of
an unfired staple cartridge state) is determined, the cutting
instrument 3034 may be enabled at step 3315. After the instrument
3010 is enabled, the operator may initiate a firing operation when
ready.
[0232] At step 3320, the transponder 3212, 3264 may be transitioned
from the first electronic state to the second electronic state
substantially simultaneously with an actuation of the cutting
instrument 3034. Accordingly, if an attempt is made to reuse the
staple cartridge 3038 at step 3300, the second electronic state of
the transponder 3212, 3264 (indicative of the fired staple
cartridge state) may be determined at step 3310 and a firing
operation consequently prevented, as shown at step 3325.
[0233] Above-described embodiments advantageously prevent operation
of the instrument 3010 when a spent staple cartridge 3038 (or no
staple cartridge 3038) is present in the end effector 3016, thus
preventing cutting of tissue without simultaneous stapling. In
addition to preventing operation of the instrument 3010 under such
circumstances, it may further be desirable to prevent operation of
the instrument 3010 after it has been used to perform a
predetermined number of firing operations. Limiting the number of
firing operations may be necessary, for example, so that use of the
instrument 3010 does not cause operational lifetimes of its various
components (e.g., the cutting instrument 3034, the battery 3104,
etc.) to be exceeded.
[0234] According to various embodiments, a limit on the number of
firing operations may be implemented by the control unit 3196
using, for example, a counter (not shown) contained within the
processor 3198. The counter may be incremented once for each firing
operation indicated by one or more sensor inputs received by the
control unit 3196 (e.g., inputs received from the end-of-stroke and
beginning-of-stroke sensors 3156, 3158 and the run-motor sensor
3128). Subsequent to each firing operation, the processor 3198 may
compare the counter contents to a predetermined number. The
predetermined number may be stored in the memory 3200 of the
processor 3198 during instrument manufacture, for example, and
represent the maximum number of firing operations performable by
the instrument 3010. The predetermined number may be determined
based upon, among other things, operational lifetimes of the
various instrument components and/or the expected requirements of a
medical procedure for which the instrument 3010 is to be used. When
the counted number of firing operations is equal to the
predetermined number, the control unit 3196 may be configured to
prevent additional firing operations by the instrument 3010. In
embodiments in which the control unit 3196 directly or indirectly
controls rotation of the motor 3106 (e.g., via a PWM signal output
in response to an input from the run-motor sensor 3128),
instruction code stored in the memory 3200 may cause the processor
3198 to prevent further output of power and/or control signals
necessary for motor operation.
[0235] In other embodiments, the control unit 3196 may prevent
firing operations in excess of the predetermined number by
disabling electronic components necessary for motor operation. For
example, as shown in FIG. 62, the control unit 3196 may be
connected to the motor 3106 via conductive leads 3268, one of which
includes an electronically-actuated fuse 3270. Subsequent to the
retraction of the cutting instrument 3034 after the final firing
operation (e.g., when the number of firing operations is equal to
the predetermined number), the control unit 3196 may cause
increased current to be applied to the motor 3106 such that the
fuse 3270 is opened (e.g., rendered non-conductive), thus
preventing further motor operation. It will be appreciated that the
placement of the fuse 3270 is shown by way of example only, and
that the fuse 3270 may be connected in other ways to effect the
same result. For example, the fuse 3270 may be connected between
the battery 3104 and the electrical components of the instrument
3010. In such embodiments, when the number of firing operations
equals the predetermined number, the control unit 3196 may short
circuit the fuse 3270 such that it is caused to open, thus removing
power from the electrical components.
[0236] As an alternative to the fuse 3270, it will be appreciated
that a switch (e.g., a relay contact) controllable by a discrete
output of the control unit 3196 may be used instead. Additionally,
it will be appreciated the control unit 3196 may be configured to
electronically disable one or more components necessary for motor
operation (e.g., capacitors, transistors, etc.) other than a fuse
by applying excessive voltages and/or currents thereto. Such
components may be internal or external to the control unit
3196.
[0237] Although above-described embodiments for limiting instrument
use utilize a counter within the processor 3198, it will be
appreciated that other embodiments may utilize an
electro-mechanical counter having a mechanical input suitably
coupled to a component of the instrument 3010 (e.g., the firing
trigger 3024) such that the counter is incremented once for each
firing operation. The counter may include a set of electrical
contacts that close (or open) when the counted number of firing
operations exceeds a predetermined number stored within the
counter. The contacts may serve as an input to the control unit
3196, and the processor 3198 may be programmed to enable or disable
instrument operation based on the state of the contacts.
Alternatively, the contacts may be connected to other components of
the instrument (e.g., the battery 3104 or the motor 3106) such that
power to the motor 3106 is interrupted when the predetermined
number of counts is exceeded.
[0238] In the embodiments described above, the battery 3104 powers
(at least partially) the firing operation of the instrument 3010.
As such, the instrument may be a so-called "power-assist" device.
More details and additional embodiments of power-assist devices are
described are described in U.S. patent application Ser. No.
11/343,573 referenced above, now U.S. Pat. No. 7,416,101, which is
incorporated herein. It should be recognized, however, that the
instrument 3010 need not be a power-assist device and that this is
merely an example of a type of device that may utilize aspects of
the present invention. For example, the instrument 3010 may include
a user display (such as a LCD or LED display) that is powered by
the battery 3104 and controlled by the control unit 3196. Data from
the transponder 3212, 3264 in the end effector 3016 may be
displayed on such a display.
[0239] In another embodiment, the shaft 3014 of the instrument
3010, including for example, the proximate closure tube 3072 and
the distal closure tube 3074, may collectively serve as part of an
antenna for the control unit 3196 by radiating signals to the
transponder 3212, 3264 and receiving radiated signals from the
transponder 3212, 3264. That way, signals to and from the
transponder 3212, 3264 in the end effector 3016 may be transmitted
via the shaft 3014 of the instrument 3010.
[0240] The proximate closure tube 3072 may be grounded at its
proximate end by the exterior lower and upper side pieces 3096,
3098, which may be made of a nonelectrically conductive material,
such as plastic. The drive shaft assembly components (including the
main drive shaft 3080 and secondary drive shaft 3082) inside the
proximate and distal closure tubes 3072, 3074 may also be made of a
nonelectrically conductive material, such as plastic. Further,
components of end effector 3016 (such as the anvil 3028 and the
channel 3026) may be electrically coupled to (or in direct or
indirect electrical contact with) the distal closure tube 3074 such
that they may also serve as part of the antenna. Further, the
transponder 3212, 3264 could be positioned such that it is
electrically insulated from the components of the shaft 3014 and
end effector 3016 serving as the antenna. For example, as discussed
above, the transponder 3212, 3264 may be positioned in the staple
cartridge 3038, which may be made of a nonelectrically conductive
material, such as plastic. Because the distal end of the shaft 3014
(such as the distal end of the distal closure tube 3074) and the
portions of the end effector 3016 serving as the antenna may be
relatively close in distance to the transponder 3212, 3264, the
power for the transmitted signals may be controlled such that
interference with other systems in the use environment of the
instrument 3010 is reduced or minimized
[0241] In such an embodiment, as shown in FIG. 59, the control unit
3196 may be electrically coupled to the shaft 3014 of the
instrument 3010, such as to the proximate closure tube 3072, by a
conductive link 3272 (e.g., a wire). Portions of the outer shaft
3014, such as the closure tubes 3072, 3074, may therefore act as
part of an antenna for the control unit 3196 by transmitting
signals to the transponder 3212, 3264 and receiving signals
transmitted by the transponder 3212, 3264. Signals received by the
control unit 3196 may be demodulated by the demodulator 3204 and
decoded by the decoder 3206, as described above.
[0242] To transmit data signals to or from the transponder 3212,
3264 in the end effector 3016, the link 3272 may connect the
control unit 3196 to components of the shaft 3014 of the instrument
3010, such as the proximate closure tube 3072, which may be
electrically connected to the distal closure tube 3074. The distal
closure tube 3074 is preferably electrically insulated from the
transponder 3212, 3264, which may be positioned in the plastic
staple cartridge 3038. As mentioned before, components of the end
effector 3016, such as the channel 3026 and the anvil 3028, may be
conductive and in electrical contact with the distal closure tube
3074 such that they, too, may serve as part of the antenna.
[0243] With the shaft 3014 acting as the antenna for the control
unit 3196, the control unit 3196 can communicate with the
transponder 3212, 3264 in the end effector 3016 without a hardwired
connection. In addition, because the distance between shaft 3014
and the transponder 3212, 3264 is fixed and known, the power levels
could be optimized to thereby minimize interference with other
systems in the use environment of the instrument 3010.
[0244] In another embodiment, the components of the shaft 3014
and/or the end effector 3016 may serve as an antenna for the
transponder 3212, 3264. In such an embodiment, the transponder
3212, 3264 is electrically connected to the shaft 3014 (such as to
distal closure tube 3074, which may be electrically connected to
the proximate closure tube 3072) and the control unit 3196 is
insulated from the shaft 3014. For example, the transponder 3212,
3264 could be connected to a conductive component of the end
effector 3016 (such as the channel 3026), which in turn may be
connected to conductive components of the shaft (e.g., the closure
tubes 3072, 3074). Alternatively, the end effector 3016 may include
a wire (not shown) that connects the transponder 3212, 3264 the
distal closure tube 3074.
[0245] FIGS. 64 and 65 depict a surgical cutting and fastening
instrument 4010 according to various embodiments of the present
invention. The illustrated embodiment is an endoscopic instrument
and, in general, the embodiments of the instrument 4010 described
herein are endoscopic surgical cutting and fastening instruments.
It should be noted, however, that according to other embodiments of
the present invention, the instrument may be a non-endoscopic
surgical cutting and fastening instrument, such as a laparoscopic
instrument.
[0246] The surgical instrument 4010 depicted in FIGS. 64 and 65
comprises a handle 4012, a shaft 4014, and an articulating end
effector 4016 pivotally connected to the shaft 4014 at an
articulation pivot 4018. An articulation control 4020 may be
provided adjacent to the handle 4012 to effect rotation of the end
effector 4016 about the articulation pivot 4018. In the illustrated
embodiment, the end effector 4016 is configured to act as an
endocutter for clamping, severing and stapling tissue, although, in
other embodiments, different types of end effectors may be used,
such as end effectors for other types of surgical devices, such as
graspers, cutters, staplers, clip appliers, access devices,
drug/gene therapy devices, ultrasound, RF or laser devices,
etc.
[0247] The handle 4012 of the instrument 4010 may include a closure
trigger 4022 and a firing trigger 4024 for actuating the end
effector 4016. It will be appreciated that instruments having end
effectors directed to different surgical tasks may have different
numbers or types of triggers or other suitable controls for
operating the end effector 4016. The end effector 4016 is shown
separated from the handle 4012 by a preferably elongate shaft 4014.
In one embodiment, an operator of the instrument 4010 may
articulate the end effector 4016 relative to the shaft 4014 by
utilizing the articulation control 4020 as described in more detail
in U.S. patent application Ser. No. 11/329,020 entitled SURGICAL
INSTRUMENT HAVING AN ARTICULATING END EFFECTOR, now U.S. Pat. No.
7,670,334, which is incorporated herein by reference.
[0248] The end effector 4016 includes in this example, among other
things, a staple channel 4026 and a pivotally translatable clamping
member, such as an anvil 4028, which are maintained at a spacing
that assures effective stapling and severing of tissue clamped in
the end effector 4016. The handle 4012 includes a pistol grip 4030
towards which a closure trigger 4022 is pivotally drawn by the
operator to cause clamping or closing of the anvil 4028 toward the
staple channel 4026 of the end effector 4016 to thereby clamp
tissue positioned between the anvil 4028 and the channel 4026. The
firing trigger 4024 is farther outboard of the closure trigger
4022. Once the closure trigger 4022 is locked in the closure
position as further described below, the firing trigger 4024 may
rotate slightly toward the pistol grip 4030 so that it can be
reached by the operator using one hand. The operator may then
pivotally draw the firing trigger 4024 toward the pistol grip 4030
to cause the stapling and severing of clamped tissue in the end
effector 4016. In other embodiments, different types of clamping
members besides the anvil 4028 may be used, such as, for example,
an opposing jaw, etc.
[0249] It will be appreciated that the terms "proximal" and
"distal" are used herein with reference to an operator gripping the
handle 4012 of an instrument 4010. Thus, the end effector 4016 is
distal with respect to the more proximal handle 4012. It will be
further appreciated that, for convenience and clarity, spatial
terms such as "vertical" and "horizontal" are used herein with
respect to the drawings. However, surgical instruments are used in
many orientations and positions, and these terms are not intended
to be limiting and absolute.
[0250] The closure trigger 4022 may be actuated first. Once the
operator is satisfied with the positioning of the end effector
4016, the operator may draw back the closure trigger 4022 to its
fully closed, locked position proximate to the pistol grip 4030.
The firing trigger 4024 may then be actuated. The firing trigger
4024 returns to the open position (shown in FIGS. 64 and 65) when
the operator removes pressure, as described more fully below. A
release button 4032 on the handle 4012, when depressed, may release
the locked closure trigger 4022. Various configurations for locking
and unlocking the closure trigger 4022 using the release button
4032 are described in U.S. patent application Ser. No. 11/343,573
entitled MOTOR-DRIVEN SURGICAL CUTTING AND FASTENING INSTRUMENT
WITH LOADING FORCE FEEDBACK, now U.S. Pat. No. 7,416,101, which is
incorporated herein by reference.
[0251] FIG. 66A is an exploded view of the end effector 4016
according to various embodiments. As shown in the illustrated
embodiment, the end effector 4016 may include, in addition to the
previously-mentioned channel 4026 and anvil 4028, a cutting
instrument 4034, a sled 4036, a staple cartridge 4038 that is
removably seated (e.g., installed) in the channel 4026, and a
helical screw shaft 4040, and FIG. 66B is a perspective view of the
cutting instrument of FIG. 66A.
[0252] The anvil 4028 may be pivotably opened and closed at a pivot
point 4042 connected to the proximate end of the channel 4026. The
anvil 4028 may also include a tab 4044 at its proximate end that is
inserted into a component of the mechanical closure system
(described further below) to open and close the anvil 4028. When
the closure trigger 4022 is actuated, that is, drawn in by an
operator of the instrument 4010, the anvil 4028 may pivot about the
pivot point 4042 into the clamped or closed position. If clamping
of the end effector 4016 is satisfactory, the operator may actuate
the firing trigger 4024, which, as explained in more detail below,
causes the cutting instrument 4034 to travel longitudinally along
the channel 4026.
[0253] As shown, the cutting instrument 4034 includes upper guide
pins 4046 that enter an anvil slot 4048 in the anvil 4028 to verify
and assist in maintaining the anvil 4028 in a closed state during
staple formation and severing. Spacing between the channel 4026 and
anvil 4028 is further maintained by the cutting instrument 4034 by
having middle pins 4050 slide along the top surface of the channel
4026 while a bottom foot 4052 opposingly slides along the
undersurface of the channel 4026, guided by a longitudinal opening
4054 in the channel 4026. A distally presented cutting surface 4056
between the upper guide pins 4046 and middle pins 4050 severs
clamped tissue while distally-presented surface 4058 actuates the
staple cartridge 4038 by progressively driving the sled 4036 from
an unfired position to a fired position. Actuation of the staple
cartridge 4038 causes staple drivers 4060 to cam upwardly, driving
staples 4062 out of upwardly open staple holes 4064 formed in the
staple cartridge 4038. The staples 4062 are subsequently formed
against a staple forming undersurface 4066 of the anvil 4028. A
staple cartridge tray 4068 encompasses from the bottom the other
components of the staple cartridge 4038 to hold them in place. The
staple cartridge tray 4068 includes a rearwardly open slot 4070
that overlies the longitudinal opening 4054 in the channel 4026. A
lower surface of the staple cartridge 4038 and an upward surface of
the channel 4026 form a firing drive slot 4200 (FIG. 69) through
which the middle pins 4050 pass during distal and proximal movement
of the cutting instrument 4034. The sled 4036 may be an integral
component of the staple cartridge 4038 such that when the cutting
instrument 4034 retracts following the cutting operation, the sled
4036 does not retract. U.S. Pat. No. 6,978,921, entitled SURGICAL
STAPLING INSTRUMENT INCORPORATING AN E-BEAM FIRING MECHANISM, which
is incorporated herein by reference, provides more details about
such two-stroke cutting and fastening instruments.
[0254] It should be noted that although the embodiments of the
instrument 4010 described herein employ an end effector 4016 that
staples the severed tissue, in other embodiments different
techniques for fastening or sealing the severed tissue may be used.
For example, end effectors that use RF energy or adhesives to
fasten the severed tissue may also be used. U.S. Pat. No. 5,709,680
entitled ELECTROSURGICAL HEMOSTATIC DEVICE, and U.S. Pat. No.
5,688,270 entitled ELECTROSURGICAL HEMOSTATIC DEVICE WITH RECESSED
AND/OR OFFSET ELECTRODES, both of which are incorporated herein by
reference, disclose cutting instruments that uses RF energy to
fasten the severed tissue. U.S. patent application Ser. No.
11/267,811 entitled SURGICAL STAPLING INSTRUMENTS STRUCTURED FOR
DELIVERY OF MEDICAL AGENTS, now U.S. Pat. No. 7,673,783, and U.S.
patent application Ser. No. 11/267,383 entitled SURGICAL STAPLING
INSTRUMENTS STRUCTURED FOR PUMP-ASSISTED DELIVERY OF MEDICAL
AGENTS, now U.S. Pat. No. 7,607,557, both of which are also
incorporated herein by reference, disclose cutting instruments that
uses adhesives to fasten the severed tissue. Accordingly, although
the description herein refers to cutting/stapling operations and
the like, it should be recognized that this is an exemplary
embodiment and is not meant to be limiting. Other tissue-fastening
techniques may also be used.
[0255] FIGS. 67 and 68 are exploded views and FIG. 69 is a side
view of the end effector 4016 and shaft 4014 according to various
embodiments. As shown in the illustrated embodiment, the shaft 4014
may include a proximate closure tube 4072 and a distal closure tube
4074 pivotably linked by a pivot links 4076. The distal closure
tube 4074 includes an opening 4078 into which the tab 4044 on the
anvil 4028 is inserted in order to open and close the anvil 4028,
as further described below. Disposed inside the closure tubes 4072,
4074 may be a proximate spine tube 4079. Disposed inside the
proximate spine tube 4079 may be a main rotational (or proximate)
drive shaft 4080 that communicates with a secondary (or distal)
drive shaft 4082 via a bevel gear assembly 4084. The secondary
drive shaft 4082 is connected to a drive gear 4086 that engages a
proximate drive gear 4088 of the helical screw shaft 4040. The
vertical bevel gear 4084b may sit and pivot in an opening 4090 in
the distal end of the proximate spine tube 4079. A distal spine
tube 4092 may be used to enclose the secondary drive shaft 4082 and
the drive gears 4086, 4088. Collectively, the main drive shaft
4080, the secondary drive shaft 4082, and the articulation assembly
(e.g., the bevel gear assembly 4084a-c) are sometimes referred to
herein as the "main drive shaft assembly."
[0256] A bearing 4094 (FIG. 69) positioned at a distal end of the
staple channel 4026 receives the helical screw shaft 4040, allowing
the helical screw shaft 4040 to freely rotate with respect to the
channel 4026. The helical screw shaft 4040 may interface a threaded
opening (not shown) of the cutting instrument 4034 such that
rotation of the helical screw shaft 4040 causes the cutting
instrument 4034 to translate distally or proximately (depending on
the direction of the rotation) through the staple channel 4026.
Accordingly, when the main drive shaft 4080 is caused to rotate by
actuation of the firing trigger 4024 (as explained in further
detail below), the bevel gear assembly 4084a-c causes the secondary
drive shaft 4082 to rotate, which in turn, because of the
engagement of the drive gears 4086, 4088, causes the helical screw
shaft 4040 to rotate, which causes the cutting instrument 4034 to
travel longitudinally along the channel 4026 to cut any tissue
clamped within the end effector 4016. The sled 4036 may be made of,
for example, plastic, and may have a sloped distal surface. As the
sled 4036 traverses the channel 4026, the sloped distal surface may
cam the staple drivers 4060 upward, which in turn push up or drive
the staples 4062 in the staple cartridge 4038 through the clamped
tissue and against the staple forming undersurface 4066 of the
anvil 4028, thereby stapling the severed tissue. When the cutting
instrument 4034 is retracted, the cutting instrument 4034 and the
sled 4036 may become disengaged, thereby leaving the sled 4036 at
the distal end of the channel 4026.
[0257] FIGS. 70-73 illustrate an exemplary embodiment of a
motor-driven endocutter, and in particular the handle 4012 thereof,
that provides operator-feedback regarding the deployment and
loading force of the cutting instrument 4034 in the end effector
4016. In addition, the embodiment may use power provided by the
operator in retracting the firing trigger 4024 to power the device
(a so-called "power assist" mode). As shown in the illustrated
embodiment, the handle 4012 includes exterior lower side pieces
4096, 4098 and exterior upper side pieces 4100, 4102 that fit
together to form, in general, the exterior of the handle 4012. A
battery 4104 may be provided in the pistol grip portion 4030 of the
handle 4012. The battery 4104 may be constructed according to any
suitable construction or chemistry including, for example, a Li-ion
chemistry such as LiCoO.sub.2 or LiNiO.sub.2, a Nickel Metal
Hydride chemistry, etc. The battery 4104 powers a motor 4106
disposed in an upper portion of the pistol grip portion 4030 of the
handle 4012. According to various embodiments, the motor 4106 may
be a DC brushed driving motor having a maximum rotation of
approximately 5000 to 100,000 RPM. The motor 4106 may drive a
90-degree bevel gear assembly 4108 comprising a first bevel gear
4110 and a second bevel gear 4112. The bevel gear assembly 4108 may
drive a planetary gear assembly 4114. The planetary gear assembly
4114 may include a pinion gear 4116 connected to a drive shaft
4118. The pinion gear 4116 may drive a mating ring gear 4120 that
drives a helical gear drum 4122 via a drive shaft 4124. A ring 4126
may be threaded on the helical gear drum 4122. Thus, when the motor
4106 rotates, the ring 4126 is caused to travel along the helical
gear drum 4122 by means of the interposed bevel gear assembly 4108,
planetary gear assembly 4114 and ring gear 4120.
[0258] The handle 4012 may also include a run motor sensor 4128 in
communication with the firing trigger 4024 to detect when the
firing trigger 4024 has been drawn in (or "closed") toward the
pistol grip portion 4030 of the handle 4012 by the operator to
thereby actuate the cutting/stapling operation by the end effector
4016. The sensor 4128 may be a proportional sensor such as, for
example, a rheostat or variable resistor. When the firing trigger
4024 is drawn in, the sensor 4128 detects the movement, and sends
an electrical signal indicative of the voltage (or power) to be
supplied to the motor 4106. When the sensor 4128 is a variable
resistor or the like, the rotation of the motor 4106 may be
generally proportional to the amount of movement of the firing
trigger 4024. That is, if the operator only draws or closes the
firing trigger 4024 in a little bit, the rotation of the motor 4106
is relatively low. When the firing trigger 4024 is fully drawn in
(or in the fully closed position), the rotation of the motor 4106
is at its maximum. In other words, the harder the operator pulls on
the firing trigger 4024, the more voltage is applied to the motor
4106, causing a greater rate of rotation. In another embodiment,
for example, a microcontroller (e.g., the microcontroller 4250 of
FIG. 92) may output a PWM control signal to the motor 4106 based on
the input from the sensor 4128 in order to control the motor
4106.
[0259] The handle 4012 may include a middle handle piece 4130
adjacent to the upper portion of the firing trigger 4024. The
handle 4012 also may comprise a bias spring 4132 connected between
posts on the middle handle piece 4130 and the firing trigger 4024.
The bias spring 4132 may bias the firing trigger 4024 to its fully
open position. In that way, when the operator releases the firing
trigger 4024, the bias spring 4132 will pull the firing trigger
4024 to its open position, thereby removing actuation of the sensor
4128, thereby stopping rotation of the motor 4106. Moreover, by
virtue of the bias spring 4132, any time an operator closes the
firing trigger 4024, the operator will experience resistance to the
closing operation, thereby providing the operator with feedback as
to the amount of rotation exerted by the motor 4106. Further, the
operator could stop retracting the firing trigger 4024 to thereby
remove force from the sensor 4128, to thereby stop the motor 4106.
As such, the operator may stop the deployment of the end effector
4016, thereby providing a measure of control of the
cutting/fastening operation to the operator.
[0260] The distal end of the helical gear drum 4122 includes a
distal drive shaft 4134 that drives a ring gear 4136, which mates
with a pinion gear 4138. The pinion gear 4138 is connected to the
main drive shaft 4080 of the main drive shaft assembly. In that
way, rotation of the motor 4106 causes the main drive shaft
assembly to rotate, which causes actuation of the end effector
4016, as described above.
[0261] The ring 4126 threaded on the helical gear drum 4122 may
include a post 4140 that is disposed within a slot 4142 of a
slotted arm 4144. The slotted arm 4144 has an opening 4146 its
opposite end 4148 that receives a pivot pin 4150 that is connected
between the handle exterior side pieces 4096, 4098. The pivot pin
4150 is also disposed through an opening 4152 in the firing trigger
4024 and an opening 4154 in the middle handle piece 4130.
[0262] In addition, the handle 4012 may include a reverse motor (or
end-of-stroke) sensor 4156 and a stop motor (or
beginning-of-stroke) sensor 4158. In various embodiments, the
reverse motor sensor 4156 may be a normally-open limit switch
located at the distal end of the helical gear drum 4122 such that
the ring 4126 threaded on the helical gear drum 4122 contacts and
closes the reverse motor sensor 4156 when the ring 4126 reaches the
distal end of the helical gear drum 4122. The reverse motor sensor
4156, when closed, sends a signal to the motor 4106 to reverse its
rotation direction, thereby retracting the cutting instrument 4034
of the end effector 4016 following a cutting operation.
[0263] The stop motor sensor 4158 may be, for example, a
normally-closed limit switch. In various embodiments, it may be
located at the proximate end of the helical gear drum 4122 so that
the ring 4126 opens the switch 4158 when the ring 4126 reaches the
proximate end of the helical gear drum 4122.
[0264] In operation, when an operator of the instrument 4010 pulls
back the firing trigger 4024, the sensor 4128 detects the
deployment of the firing trigger 4024 and sends a signal to the
motor 4106 to cause forward rotation of the motor 4106 at, for
example, a rate proportional to how hard the operator pulls back
the firing trigger 4024. The forward rotation of the motor 4106 in
turn causes the ring gear 4120 at the distal end of the planetary
gear assembly 4114 to rotate, thereby causing the helical gear drum
4122 to rotate, causing the ring 4126 threaded on the helical gear
drum 4122 to travel distally along the helical gear drum 4122. The
rotation of the helical gear drum 4122 also drives the main drive
shaft assembly as described above, which in turn causes deployment
of the cutting instrument 4034 in the end effector 4016. That is,
the cutting instrument 4034 and sled 4036 are caused to traverse
the channel 4026 longitudinally, thereby cutting tissue clamped in
the end effector 4016. Also, the stapling operation of the end
effector 4016 is caused to happen in embodiments where a
stapling-type end effector is used.
[0265] By the time the cutting/stapling operation of the end
effector 4016 is complete, the ring 4126 on the helical gear drum
4122 will have reached the distal end of the helical gear drum
4122, thereby causing the reverse motor sensor 4156 to be actuated,
which sends a signal to the motor 4106 to cause the motor 4106 to
reverse its rotation. This in turn causes the cutting instrument
4034 to retract, and also causes the ring 4126 on the helical gear
drum 4122 to move back to the proximate end of the helical gear
drum 4122.
[0266] The middle handle piece 4130 includes a backside shoulder
4160 that engages the slotted arm 4144 as best shown in FIGS. 71
and 72. The middle handle piece 4130 also has a forward motion stop
4162 that engages the firing trigger 4024. The movement of the
slotted arm 4144 is controlled, as explained above, by rotation of
the motor 4106. When the slotted arm 4144 rotates CCW as the ring
4126 travels from the proximate end of the helical gear drum 4122
to the distal end, the middle handle piece 4130 will be free to
rotate CCW. Thus, as the operator draws in the firing trigger 4024,
the firing trigger 4024 will engage the forward motion stop 4162 of
the middle handle piece 4130, causing the middle handle piece 4130
to rotate CCW. Due to the backside shoulder 4160 engaging the
slotted arm 4144, however, the middle handle piece 4130 will only
be able to rotate CCW as far as the slotted arm 4144 permits. In
that way, if the motor 4106 should stop rotating for some reason,
the slotted arm 4144 will stop rotating, and the operator will not
be able to further draw in the firing trigger 4024 because the
middle handle piece 4130 will not be free to rotate CCW due to the
slotted arm 4144.
[0267] FIGS. 74 and 75 illustrate two states of a variable sensor
that may be used as the run motor sensor 4128 according to various
embodiments of the present invention. The sensor 4128 may include a
face portion 4164, a first electrode (A) 4166, a second electrode
(B) 4168, and a compressible dielectric material 4170 (e.g., EAP)
between the electrodes 4166, 4168. The sensor 4128 may be
positioned such that the face portion 4164 contacts the firing
trigger 4024 when retracted. Accordingly, when the firing trigger
4024 is retracted, the dielectric material 4170 is compressed, as
shown in FIG. 75, such that the electrodes 4166, 4168 are closer
together. Since the distance "b" between the electrodes 4166, 4168
is directly related to the impedance between the electrodes 4166,
4168, the greater the distance the more impedance, and the closer
the distance the less impedance. In that way, the amount that the
dielectric material 4170 is compressed due to retraction of the
firing trigger 4024 (denoted as force "F" in FIG. 75) is
proportional to the impedance between the electrodes 4166, 4168,
which can be used to proportionally control the motor 4106.
[0268] Components of an exemplary closure system for closing (or
clamping) the anvil 4028 of the end effector 4016 by retracting the
closure trigger 4022 are also shown in FIGS. 70-73. In the
illustrated embodiment, the closure system includes a yoke 4172
connected to the closure trigger 4022 by a pin 4174 that is
inserted through aligned openings in both the closure trigger 4022
and the yoke 4172. A pivot pin 4176, about which the closure
trigger 4022 pivots, is inserted through another opening in the
closure trigger 4022 which is offset from where the pin 4174 is
inserted through the closure trigger 4022. Thus, retraction of the
closure trigger 4022 causes the upper part of the closure trigger
4022, to which the yoke 4172 is attached via the pin 4174, to
rotate CCW. The distal end of the yoke 4172 is connected, via a pin
4178, to a first closure bracket 4180. The first closure bracket
4180 connects to a second closure bracket 4182. Collectively, the
closure brackets 4180, 4182 define an opening in which the proximal
end of the proximate closure tube 4072 (see FIG. 67) is seated and
held such that longitudinal movement of the closure brackets 4180,
4182 causes longitudinal motion by the proximate closure tube 4072.
The instrument 4010 also includes a closure rod 4184 disposed
inside the proximate closure tube 4072. The closure rod 4184 may
include a window 4186 into which a post 4188 on one of the handle
exterior pieces, such as exterior lower side piece 4096 in the
illustrated embodiment, is disposed to fixedly connect the closure
rod 4184 to the handle 4012. In that way, the proximate closure
tube 4072 is capable of moving longitudinally relative to the
closure rod 4184. The closure rod 4184 may also include a distal
collar 4190 that fits into a cavity 4192 in proximate spine tube
4079 and is retained therein by a cap 4194 (see FIG. 67).
[0269] In operation, when the yoke 4172 rotates due to retraction
of the closure trigger 4022, the closure brackets 4180, 4182 cause
the proximate closure tube 4072 to move distally (i.e., away from
the handle 4012 of the instrument 4010), which causes the distal
closure tube 4074 to move distally, which causes the anvil 4028 to
rotate about the pivot point 4042 into the clamped or closed
position. When the closure trigger 4022 is unlocked from the locked
position, the proximate closure tube 4072 is caused to slide
proximally, which causes the distal closure tube 4074 to slide
proximally, which, by virtue of the tab 4044 being inserted in the
opening 4078 of the distal closure tube 4074, causes the anvil 4028
to pivot about the pivot point 4042 into the open or unclamped
position. In that way, by retracting and locking the closure
trigger 4022, an operator may clamp tissue between the anvil 4028
and channel 4026, and may unclamp the tissue following the
cutting/stapling operation by unlocking the closure trigger 4022
from the locked position.
[0270] According to various embodiments, the instrument 4010 may
include an interlock for preventing instrument 4010 operation when
the staple cartridge 4038 is not installed in the channel 4026, or
when the staple cartridge 4038 is installed in the channel 4026 but
spent. Operation of the interlock is twofold. First, in the absence
of an unspent staple cartridge 4038 within the channel 4026, the
interlock operates to mechanically block distal advancement of the
cutting instrument 4034 through the channel 4026 in response to
actuation of the firing trigger 4024. Using suitable electronics
disposed within the handle 4012, the interlock next detects the
increase in current through the motor 4106 resulting from the
immobilized cutting instrument 4034 and consequently interrupts
current to the motor 4106. Advantageously, the interlock eliminates
the need for electronic sensors in the end effector 4016, thus
simplifying instrument design. Moreover, because the magnitude and
duration of mechanical blocking force needed to produce the
detected increase in motor current is significantly less than that
which would be exerted if only a conventional mechanical interlock
was used, physical stresses experienced by instrument components
are reduced.
[0271] According to various embodiments, the interlock may include
(1) a blocking mechanism to prevent actuation of the cutting
instrument 4034 by the motor 4106 when an unspent staple cartridge
4038 is not installed in the channel 4026, and (2) a lockout
circuit to detect the current through the motor 4106 and to
interrupt the current through the motor 4106 based on the sensed
current.
[0272] FIG. 94 is a flow diagram of the process implemented by the
interlock according to various embodiments. At step 4264, the
actuation of the cutting instrument 4034 by the motor 4106 is
mechanically blocked by the blocking mechanism in the absence of an
unspent staple cartridge 4038 within the channel 4026. As discussed
below, the blocking mechanism may include components or features of
conventional mechanical interlocks.
[0273] At step 4266, the current through the motor 4106 resulting
from the blocked actuation of the cutting instrument 4034 is
detected by the lockout circuit. As discussed below, detection of
the current may include, for example, the steps of sensing the
motor current, generating a signal representative of the sensed
motor current, and comparing the generated signal to a threshold
signal.
[0274] At step 4268, the current through the motor 4106 is
interrupted based on the detected current. Interrupting the current
may include, for example, interrupting the current when the result
of the comparison at step 4266 indicates that the generated signal
exceeds the threshold signal. Interrupting the current through the
motor 4106 may further include interrupting the current based on a
position of the cutting instrument 4034.
[0275] According to various embodiments, the blocking mechanism of
the interlock may include features similar or identical to those of
conventional mechanical interlocks for physically blocking
advancement of the cutting instrument 4034 in the absence of an
unspent staple cartridge 4038 within the channel 4026. FIG. 76
illustrates a blocking mechanism 4196 according to one embodiment.
As shown, the blocking mechanism 4196 may comprise a pair of spring
fingers 4198 positioned in the channel 4026. In particular, the
spring fingers 4196 may raise up to block the middle pins 4050 of
the cutting instrument 4034 when the sled 4036 (not shown in FIG.
76) is not present in an unfired position at the proximal end of
the channel 4026, such as when the staple cartridge 4038 is not
installed or when the staple cartridge 4038 is installed but spent.
Although two spring fingers 4198 are shown, it will be appreciated
that more or fewer spring fingers 4198 may be used instead.
[0276] FIGS. 77-80 depict the operation of the spring fingers 4198
sequentially as the instrument 4010 is fired. In FIG. 77, an
unspent staple cartridge 4038 has been inserted into the channel
4026. The presence of the sled 4036 in its unfired position
depresses the spring fingers 4198 such that the firing drive slot
4200 through which the middle pins 4050 will pass is unimpeded.
[0277] In FIG. 78, firing of the staple cartridge 4038 has
commenced, with the sled 4036 and the middle pins 4050 of the
cutting instrument 4034 having distally traversed off of the spring
fingers 4198, which then spring up into the firing drive slot
4200.
[0278] In FIG. 79, the staple cartridge 4038 is now spent with the
sled 4036 fully driven distally and no longer depicted. The cutting
instrument 4034 is being retracted proximally. Since the spring
fingers 4198 pivot from a more distal point, the middle pins 4050
of the cutting instrument 4034 are able to ride up onto the spring
fingers 4198 during retraction, causing them to be depressed out of
the firing drive slot 4200.
[0279] In FIG. 80, the cutting instrument 4034 is fully retracted
and now confronts the non-depressed pair of spring fingers 4198 to
prevent distal movement. The blocking mechanism 4196 thereby
remains activated until an unspent staple cartridge 4038 is
installed in the channel 4026.
[0280] FIG. 81 depicts a blocking mechanism 4202 according to
another embodiment. The blocking mechanism 4202, which is disclosed
in U.S. Pat. No. 7,044,352 referenced above, includes a pair of
hooks 4204 having ramped ends 4206 distally placed with regard to
attachment devices 4208. The attachment devices 4208 are inserted
through apertures 4210 in the channel 4026, thereby springedly
attaching the hooks 4204 to the channel 4026. The ramped ends 4206
lie above a hook recess 4212 defined in the channel 4026. Thus,
when each ramped end 4206 is contacted by the sled 4036 of an
unspent staple cartridge 4038 (not shown in FIG. 81), the ramped
ends 4206 are depressed into the hook recess 4212, thereby clearing
the way for the middle pins 4050 of the cutting instrument 4034 to
move distally through the firing drive slot 4200 so that the staple
cartridge 4038 may be actuated. A thin shaft 4214 coupling the
attachment devices 4208 respectively to the ramped end 4206 of each
hook 4204 resiliently responds to absence of the sled 4036, as
depicted, wherein the ramped ends 4206 return to impede the firing
drive slot 4200 to block the retracted middle pins 4050 of the
cutting instrument 4034. Although two hooks 4204 are shown, it will
be appreciated that more or fewer hooks 4204 may be used
instead.
[0281] FIGS. 82-85 depict the sequence of operation of the hooks
4204. In FIG. 82, the staple cartridge 4038 is unspent so that the
distally positioned sled 4036 depresses the ramped ends 4206 into
the hook recess 4212, allowing the middle pins 4050 of the cutting
instrument 4034 to move distally through the firing drive slot 4200
during firing, as depicted in FIG. 83. With the sled 4036 and
middle pins 4050 distally removed with respect to the blocking
mechanism 4202, the ramped ends 4206 resiliently raise out of the
hook recess 4212 to occupy the firing drive slot 4200.
[0282] In FIG. 84, the cutting instrument 4034 is being retracted
to the point of contacting the ramped ends 4206 of the hooks 4204.
Since the distal end of the ramped ends 4206 is lower than the
proximal part of the ramped ends 4206, the middle pins 4050 of the
cutting instrument 4034 ride over the ramped ends 4206, forcing
them down into the hook recess 4212 until the middle pins 4050 are
past the ramped ends 4206, as depicted in FIG. 85, wherein the
ramped ends 4206 resiliently spring back up to block the middle
pins 4050. Thus, the cutting instrument 4034 is prevented from
distal movement until an unspent staple cartridge 4038 is installed
in the channel 4026.
[0283] FIG. 86 depicts a blocking mechanism 4216 according to yet
another embodiment. The blocking mechanism 4216 is integrally
formed with the staple cartridge 4038 and includes proximally
projecting blocking members 4218 resiliently positioned above the
sled 4036 (not shown in FIG. 86). In particular, the blocking
members 4218 each reside within a downward and proximally opening
cavity 4220. Each blocking member 4218 includes a leaf spring end
4222 that is held within the cavity 4220.
[0284] The cavities 4220 are vertically aligned and spaced and
parallel about a proximally presented vertical slot 4224 in the
staple cartridge 4038 through which the cutting surface 4056 (not
shown in FIG. 86) passes. The staple cartridge 4038 also includes
slots 4226 that longitudinally pass through the staple cartridge
4038, being open from a portion of a proximal and underside of the
staple cartridge 4038 to receive the sled 4036.
[0285] Each blocking member 4218 has a deflectable end 4228 having
a ramped distal side 4227 and blocking proximal side 4229. The
blocking members 4218 are shaped to reside within their respective
cavities 4220 when depressed and to impede the distally moving
middle pins 4050 of the cutting instrument 4034 when released.
[0286] FIGS. 87-90 depict the blocking mechanism 4216 sequentially
as the instrument 4010 is fired. In FIG. 87, an unspent staple
cartridge 4038 has been inserted into the channel 4026 with the
sled 4036 depressing upward the deflectable ends 4228 so that the
firing drive slot 4200 is unimpeded.
[0287] In FIG. 88, firing of the staple cartridge 4038 has
commenced, with the sled 4036 and the middle pins 4050 of the
cutting instrument 4034 having distally traversed past the
deflectable ends 4228, which then spring down into the firing drive
slot 4200.
[0288] In FIG. 89, the staple cartridge 4038 is now spent with the
sled 4036 fully driven distally and no longer depicted. The cutting
instrument 4034 is being retracted proximally. Since the
deflectable ends 4228 pivot from a more distal point, the middle
pins 4050 of the cutting instrument 4034 are able to ride under the
ramped distal sides 4227 of the deflectable ends 4228 during
retraction, causing them to be depressed up, out of the firing
drive slot 4200.
[0289] In FIG. 90, the cutting instrument 4034 is fully retracted
and the middle pints 4050 now confront the blocking proximal sides
4229 of the non-depressed (released) pair of deflectable ends 4228
to prevent distal movement. The blocking mechanism 4216 thereby
remains activated until an unspent staple cartridge 4038 is
installed in the channel 4026.
[0290] The blocking mechanisms 4196, 4202, 4216 of the
above-discussed embodiments are provided by way of example only. It
will be appreciated that other suitable blocking mechanisms may be
used instead.
[0291] FIG. 91 is a schematic diagram of an electrical circuit 4231
of the instrument 4010 according to various embodiments of the
present invention. In certain embodiments, the circuit 4231 may be
housed within the handle 4012. In addition to the sensor 4128,
sensors 4156, 4158 (depicted as a normally-open limit switch and a
normally-closed limit switch, respectively), the battery 4104, and
the motor 4106, the circuit 4231 may include a single-pole
double-throw relay 4230, a single-pole single-throw relay 4232, a
double-pole double-throw relay 4234, a current sensor 4236, a
position sensor 4238, and a current detection module 4240. Relay
4232, the current sensor 4236, the position sensor 4238, and the
current detection module 4240 collectively form a lockout circuit
4241. As described below, the lockout circuit 4241 operates to
sense the current through the motor 4106 and to interrupt the
current based upon the sensed current, thus "locking out" the
instrument 4010 by disabling its operation.
[0292] As described above, sensor 4128 is activated when an
operator pulls in the firing trigger 4024 after locking the closure
trigger 4022. When switch 4156 is open (indicating that the
cutting/stapling operation of the end effector 4016 is not yet
complete), coil 4242 of relay 4230 is de-energized, thus forming a
conductive path between the battery 4104 and relay 4232 via a
normally-closed contact of relay 4230. Coil 4244 of relay 4232 is
controlled by the current detection module 4240 and the position
sensor 4238 as described below. When coil 4244 is de-energized and
coil 4242 is de-energized, a conductive path between the battery
4104 and a normally-closed contact of relay 4234 is formed. Relay
4234 controls the rotational direction of the motor 4106 based on
the states of switches 4156, 4158. When switch 4156 is open and
switch 4158 is closed (indicating that the cutting instrument 4034
has not yet fully deployed distally), coil 4246 of relay 4234 is
de-energized. Accordingly, when coils 4242, 4244, 4246 are
collectively de-energized, current from the battery 4104 flows
through the motor 4106 via the normally-closed contacts of relay
4234 and causes the forward rotation of the motor 4106, which in
turn causes distal deployment of the cutting instrument 4034 as
described above.
[0293] When switch 4156 is closed (indicating that the cutting
instrument 4034 has fully deployed distally), coil 4242 of relay
4230 is energized, and coil 4246 of relay 4234 is energized via a
normally-open contact of relay 4230. Accordingly, current now flows
to the motor 4106 via normally-open contacts of relays 4230, 4234,
thus causing reverse rotation of the motor 4106 which in turn
causes the cutting instrument 4034 to retract from its distal
position and switch 4156 to open. Coil 4242 of relay 4230 remains
energized until limit switch 4158 is opened, indicating the
complete retraction of the cutting instrument 4034.
[0294] The magnitude of current through the motor 4106 during its
forward rotation is indicative of forces exerted upon the cutting
instrument 4034 during its deployment. As described above, the
absence of an unspent staple cartridge 4038 in the channel 4026
(e.g., the presence of a spent staple cartridge 4038 or the absence
of a staple cartridge 4038 altogether) results in activation of the
blocking mechanism 4196, 4202, 4216 such that distal movement of
the cutting instrument 4034 is prevented. The resistive force
exerted by the blocking mechanism 4196, 4202, 4216 against the
cutting instrument 4034 causes an increase in motor torque, thus
causing motor current to increase to a level that is measurably
greater than that present during a cutting and stapling operation.
Accordingly, by sensing the current through the motor 4106, the
lockout circuit 4241 may differentiate between deployment of the
cutting instrument 4034 when an unspent cartridge 4038 is installed
in the channel 4026 versus deployment of the cutting instrument
4034 when an unspent cartridge 4038 is absent from the channel
4026.
[0295] The current sensor 4236 may be coupled to a path of the
circuit 4231 that conducts current to the motor 4106 during its
forward rotation. The current sensor 4236 may be any current
sensing device (e.g., a shunt resistor, a Hall effect current
transducer, etc.) suitable for generating a signal (e.g., a voltage
signal) representative of sensed motor current. The generated
signal may be input to the current detection module 4240 for
processing therein, as described below.
[0296] According to various embodiments, the current detection
module 4240 may be configured for comparing the signal generated by
the current sensor 4236 to a threshold signal (e.g., a threshold
voltage signal) to determine if the blocking mechanism 4196, 4202,
4216 has been activated. For a given instrument 4010, a suitable
value of the threshold signal may be empirically determined a
priori by, for example, measuring the peak signal generated by the
current sensor 4236 when the cutting instrument 4034 is initially
deployed (e.g., over the first 0.06 inches of its distal movement)
during a cutting and stapling operation, and when the cutting
instrument 4034 is deployed and encounters the activated blocking
mechanism 4196, 4202, 4216. The threshold signal value may be
selected to be less than the peak signal measured when the blocking
mechanism 4196, 4202, 4216 is activated, but larger than the peak
signal measured during a cutting and stapling operation.
[0297] In certain embodiments and as shown in FIG. 91, the current
detection module 4240 may comprise a comparator circuit 4248 for
receiving the threshold and current sensor 4236 signals and
generating a discrete output based on a comparison of the received
signals. For example, the comparator circuit 4248 may generate a 5
VDC output when the threshold signal is exceeded and a 0VDC output
when the threshold signal is not exceeded. The threshold signal may
be generated, for example, using a suitable signal reference
circuit (e.g., a voltage reference circuit) (not shown). The design
and operation of the comparator circuit 4248 and signal reference
circuit are well known in the art and are not described further
herein.
[0298] The result of the threshold and current sensor 4236 signal
comparison is primarily of interest during the initial deployment
(e.g., during the first 0.06 inches of distal movement) of the
cutting instrument 4034. Accordingly, the current detection module
4240 may limit the comparison based on the distal position of the
cutting instrument 4034 as indicated by the position sensor 4238.
The position sensor 4238 may be any type of position sensing device
suitable for generating a signal indicative of a distal position of
the cutting instrument 4034. In one embodiment and as shown in FIG.
91, for example, the position sensor 4238 may be a normally-open
Hall effect position switch 4238 that is actuated based on its
proximity to a magnet mounted on the ring 4126. The position switch
4238 may mounted within the handle 4012 and operate such that when
the distal position of the cutting instrument 4034 (as indicated by
the position of ring 4126) is within a pre-determined distance
(e.g., distal position <0.06 inches) of its proximal-most
position, the position switch 4238 is closed. Conversely, when the
distal position of the cutting instrument 4034 exceeds the
predetermined distance (e.g., distal position >0.06 inches), the
position switch 4238 is opened. The position switch 4238 may be
connected in series with the output of the comparator circuit 4248
to limit the comparison based on the position of the cutting
instrument 4034. In this way, if the threshold signal is exceeded
when the distal position of the cutting instrument 4034 is greater
than pre-determined distance, the output of the position switch
4238 will remain at 0VDC (according to the example presented
above), regardless of the result of the comparison. It will be
appreciated that other types of position sensors 4238 (e.g.,
mechanically-actuated limit switches, rotary potentiometers, etc.)
may be used instead as an alternative to the Hall effect position
switch 4238 described above. Additionally, it will be appreciated
that auxiliary contacts (not shown) of switch 4158 may be used as
an alternative to a separate position sensor 4238. In embodiments
in which the position sensor 4238 does not include a switched
output (e.g., when the position sensor 4238 is a potentiometer or
other analog-based position sensor), additional processing of the
position sensor 4236 output using, for example, a second comparator
circuit, may be necessary.
[0299] As shown in FIG. 91, the output of the position switch 4238
may be connected to coil 4244 of relay 4232. Driver circuitry (not
shown) between the position switch 4238 and the coil 4244 may be
provided if necessary. Accordingly, if the signal generated by the
current sensor 4236 exceeds the threshold signal (indicating
activation of the blocking mechanism 4196, 4202, 4216 due to the
absence of an unspent staple cartridge 4038), and the cutting
instrument 4034 is within the predetermined distance of its
proximal-most position, coil 4244 will be energized. This causes
normally-closed switch of relay 4232 to open, thereby interrupting
current flow to the motor 4106 and removing the resistive force
exerted by the blocking mechanism 4196, 4202, 4216 upon the cutting
instrument 4034. Importantly, because the blocking mechanism 4196,
4202, 4216 need only apply a mechanical blocking force sufficient
to cause the threshold signal to be exceeded, the physical stresses
exerted by the blocking mechanism 4196, 4202, 4216 are reduced in
magnitude and duration compared to those that would be exerted if
only conventional mechanical interlocks were used. Furthermore,
because the interlock does not require electronic sensors in the
end effector 4016, instrument design is simplified.
[0300] FIG. 92 is a schematic diagram of an electrical circuit 4249
of the instrument 4010 according to another other embodiment of the
present invention in which a processor-based microcontroller 4250
is used to implement functionality of the lockout circuit 4241
described above. Although not shown for purposes of clarity, the
microcontroller 4250 may include components well known in the
microcontroller art such as, for example, a processor, a random
access memory (RAM) unit, an erasable programmable read-only memory
(EPROM) unit, an interrupt controller unit, timer units,
analog-to-digital conversion (ADC) and digital-to-analog conversion
(DAC) units, and a number of general input/output (I/O) ports for
receiving and transmitting digital and analog signals. The current
sensor 4236 and the position sensor 4238 may be connected to analog
and digital inputs, respectively, of the microcontroller 4250, and
the coil 4244 of relay 4232 may be connected to a digital output of
the microcontroller 4250. It will be appreciated that in
embodiments in which the output of the position sensor 4238 is an
analog signal, the position sensor 4238 may be connected to an
analog input instead. Additionally, although the circuit 4249 of
FIG. 92 includes relays 4230, 4232, 4234, it will be appreciated
that in other embodiments the relay switching functionality may be
replicated using solid state switching devices, software, and
combinations thereof. In certain embodiments, for example,
instructions stored and executed in the microcontroller 4250 may be
used to control solid state switched outputs of the microcontroller
4250. In such embodiments, switches 4156, 4158 may be connected to
digital inputs of the microcontroller 4250.
[0301] FIG. 93 is a flow diagram of a process implemented by the
microcontroller 4250 according to various embodiments. At step
4252, the microcontroller 4250 receives the signal generated by the
current sensor 4236 via an analog input and converts the received
signal into a corresponding digital current sensor signal.
[0302] At step 4254, values of the digital current sensor signal
are compared to a digital threshold value stored within the
microcontroller 4250. The digital threshold value may be, for
example, a digitized representation of the threshold signal
discussed above in connection with FIG. 91. If all values of the
digital current sensor signal are less than the digital threshold
value, the process terminates at step 4256. If a value of the
digital current sensor signal exceeds the digital threshold value,
the process proceeds to step 4258.
[0303] At step 4258, the position sensor 4238 input is processed to
determine if the cutting instrument 4034 is within the
predetermined distance of its proximal-most position. If the
cutting instrument 4034 is not within the predetermined distance,
the process is terminates at step 4260. If the cutting instrument
4034 is within the predetermined distance, the process proceeds to
step 4262.
[0304] At step 4262, the digital output to corresponding to coil
4244 is energized, thus causing the normally closed contacts of
relay 4232 to open, which in turn interrupts the current flow to
the motor 4106.
[0305] Although embodiments described above compare the magnitude
of the current sensor signal (or a digitized version thereof) to a
threshold signal or value, it will be appreciated that other
metrics for analyzing the current sensor signal may additionally or
alternatively be used to differentiate between deployment of the
cutting instrument 4034 when an unspent cartridge 4038 is installed
in the channel 4026 versus deployment of the cutting instrument
4034 when an unspent cartridge 4038 is absent from the channel
4026. For example, the current detection module 4240 or the
microcontroller 4250 may be configured to determine derivative
and/or integral characteristics of the current sensor signal for
comparison to corresponding thresholds signals or values.
Additionally, in certain embodiments the current sensor signal may
be processed prior to its analysis using, for example, signal
conditioners and/or filters implementing one or more filter
response functions (e.g., infinite impulse response functions).
[0306] The various embodiments of the present invention have been
described above in connection with cutting-type surgical
instruments. It should be noted, however, that in other
embodiments, the inventive surgical instrument disclosed herein
need not be a cutting-type surgical instrument, but rather could be
used in any type of surgical instrument including remote sensor
transponders. For example, it could be a non-cutting endoscopic
instrument, a grasper, a stapler, a clip applier, an access device,
a drug/gene therapy delivery device, an energy device using
ultrasound, RF, laser, etc. In addition, the present invention may
be in laparoscopic instruments, for example. The present invention
also has application in conventional endoscopic and open surgical
instrumentation as well as robotic-assisted surgery.
[0307] The devices disclosed herein can be designed to be disposed
of after a single use, or they can be designed to be used multiple
times. In either case, however, the device can be reconditioned for
reuse after at least one use. Reconditioning can include any
combination of the steps of disassembly of the device, followed by
cleaning or replacement of particular pieces, and subsequent
reassembly. In particular, the device can be disassembled, and any
number of the particular pieces or parts of the device can be
selectively replaced or removed in any combination. Upon cleaning
and/or replacement of particular parts, the device can be
reassembled for subsequent use either at a reconditioning facility,
or by a surgical team immediately prior to a surgical procedure.
Those skilled in the art will appreciate that reconditioning of a
device can utilize a variety of techniques for disassembly,
cleaning/replacement, and reassembly. Use of such techniques, and
the resulting reconditioned device, are all within the scope of the
present application.
[0308] Although the present invention has been described herein in
connection with certain disclosed embodiments, many modifications
and variations to those embodiments may be implemented. For
example, different types of end effectors may be employed. Also,
where materials are disclosed for certain components, other
materials may be used. The foregoing description and following
claims are intended to cover all such modification and
variations.
[0309] Any patent, publication, or other disclosure material, in
whole or in part, that is said to be incorporated by reference
herein is incorporated herein only to the extent that the
incorporated materials does not conflict with existing definitions,
statements, or other disclosure material set forth in this
disclosure. As such, and to the extent necessary, the disclosure as
explicitly set forth herein supersedes any conflicting material
incorporated herein by reference. Any material, or portion thereof,
that is said to be incorporated by reference herein, but which
conflicts with existing definitions, statements, or other
disclosure material set forth herein will only be incorporated to
the extent that no conflict arises between that incorporated
material and the existing disclosure material.
* * * * *