U.S. patent application number 10/420197 was filed with the patent office on 2005-04-07 for pneumatic circuit.
Invention is credited to Schwindt, Jeffrey.
Application Number | 20050075581 10/420197 |
Document ID | / |
Family ID | 29219020 |
Filed Date | 2005-04-07 |
United States Patent
Application |
20050075581 |
Kind Code |
A1 |
Schwindt, Jeffrey |
April 7, 2005 |
Pneumatic circuit
Abstract
A pneumatic circuit and other components are provided for the
operation of a medical device. The pneumatic circuit provides
controlled pressurized air to a medical device for use during a
medical procedure.
Inventors: |
Schwindt, Jeffrey;
(Indianapolis, IN) |
Correspondence
Address: |
BARNES & THORNBURG
11 SOUTH MERIDIAN
INDIANAPOLIS
IN
46204
|
Family ID: |
29219020 |
Appl. No.: |
10/420197 |
Filed: |
April 22, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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60374952 |
Apr 23, 2002 |
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Current U.S.
Class: |
600/568 ;
600/566 |
Current CPC
Class: |
A61M 1/0058 20130101;
A61B 10/0283 20130101 |
Class at
Publication: |
600/568 ;
600/566 |
International
Class: |
A61B 010/00 |
Claims
1. A medical device comprising: a biopsy device comprising a
cannula with an orifice, the cannula being configured for insertion
into a body to a point such that the orifice is adjacent to a
tissue mass to be biopsied, a cutter housed within the cannula and
configured to move relative to the orifice to selectively cut
tissue from the mass, and a pneumatic cylinder coupled to the
cutter for moving the cutter relative to the orifice; and a
pneumatic circuit coupled to the biopsy device for controlling the
pneumatic cylinder, the pneumatic circuit comprising a sensor
configured to sense back pressure in the pneumatic cylinder.
2. The medical device of claim 1, wherein the cannula defines an
axis and the cutter is aligned coaxially with the cannula.
3. The medical device of claim 2, wherein the cutter rotates about
the axis.
4. The medical device of claim 2, further comprising a pneumatic
motor controlled by the pneumatic circuit, the pneumatic motor
actuating rotational movement of the cutter.
5. The medical device of claim 2, wherein the pneumatic circuit
selectively causes the cutter to rotate relative to the cannula as
the cutter approaches and closes the orifice and the pneumatic
circuit further selectively causes the cutter to retract to a
retracted position without rotating.
6. The medical device of claim 5, wherein the pneumatic circuit
provides a signal to the operator when the cutter has completed one
cycle of moving between the closed-orifice position and the
retracted position and back.
7. The medical device of claim 2, wherein the pneumatic cylinder
causes the cutter to move axially relative to the cannula.
8. The medical device of claim 1, wherein the pneumatic circuit
directs the retraction of the cutter relative to the orifice when a
predetermined back pressure is sensed in the pneumatic
cylinder.
9. The medical device of claim 7, wherein the predetermined back
pressure is approximately 24 pounds per square inch.
10. The medical device of claim 1, further comprising a pneumatic
switch configured to permit an operator to selectively operate the
cutter by actuating the pneumatic switch.
11. The medical device of claim 1, wherein the biopsy device is
substantially free of magnetically sensitive objects such that it
can be operated in conjunction with a Magnetic Resonance Imaging
device.
12. The medical device of claim 1, further comprising a saline
supply coupled to the biopsy device, the saline supply dispensing
saline in a manner controlled by the pneumatic circuit.
13. The medical device of claim 12, wherein the saline is directed
between the cutter and the cannula.
14. The medical device of claim 12, further comprising a vacuum
coupled to the biopsy device for creating a suction and drawing the
saline through the cannula.
15. A medical device comprising: a cutter configured to selectively
cut tissue from a body; a pneumatic cylinder coupled to the cutter
for moving the cutter relative to the body; and a pneumatic circuit
coupled to the pneumatic cylinder for controlling the pneumatic
cylinder, the pneumatic circuit sensing the back pressure in the
pneumatic cylinder and responsively controlling the pneumatic
cylinder.
16. The medical device of claim 15, further comprising a pneumatic
motor, wherein the cutter defines an axis and the pneumatic motor
causes the cutter to rotate about its axis as the cutter is cutting
tissue from the body.
17. The medical device of claim 15, wherein the pneumatic circuit
provides a signal to the operator when the cutter has completed one
cycle of cutting tissue from the body.
18. The medical device of claim 15, wherein the pneumatic circuit
directs the retraction of the cutter relative to the body when a
predetermined back pressure is sensed in the pneumatic
cylinder.
19. The medical device of claim 18, wherein the predetermined back
pressure is approximately 24 pounds per square inch.
20. The medical device of claim 15, further comprising a pneumatic
switch coupled to the cutter for selectively operating the
cutter.
21. The medical device of claim 20, wherein the pneumatic switch is
foot pedal operated.
22. The medical device of claim 20, wherein the pneumatic circuit
uses the pneumatic switch as an indication of whether to initiate
another cutting cycle.
23. The medical device of claim 15, further comprising a saline
supply for dispensing saline in a manner controlled by the
pneumatic circuit.
24. The medical device of claim 23, wherein the saline is directed
to flow around the cutter, providing lubrication to the cutter and
providing a flush for tissue cut from the body by the cutter.
25. The medical device of claim 15, further comprising a vacuum
coupled to the biopsy device, the vacuum being controlled by the
pneumatic circuit.
26. The medical device of claim 25, wherein the vacuum is used to
facilitate the removal of tissue after the tissue has been cut from
the body.
27. The medical device of claim 15, wherein the tissue is breast
tissue.
28. A method of removing a tissue mass from a body, the method
comprising the steps of: inserting a hollow cannula having an
aperture into the body such that the aperture is positioned
adjacent to the tissue mass, the hollow cannula housing a cutter
therein; providing suction to the cannula such that a portion of
the tissue mass is pulled inside the cannula through the aperture;
pneumatically moving the cutter relative to the aperture so that
the cutter cuts the portion of tissue mass from the remainder of
the tissue mass; and transporting the cut portion of tissue mass
through the cannula with the provided suction, wherein the
pneumatic movement of the cutter is controlled by a pneumatic
circuit comprising a pressure sensor.
29. The method of claim 28, wherein the step of moving the cutter
across the aperture is repeated such that additional portions of
the tissue mass are removed.
30. The method of claim 28, wherein the cutter is rotating as it
cuts the portion of tissue mass.
31. The method of claim 30, wherein the rotation of the cutter is
pneumatically actuated by a pneumatic motor.
32. The method of claim 28, wherein the movement of the cutter is
pneumatically actuated by a pneumatic cylinder.
33. The method of claim 28, wherein the pneumatic circuit controls
the provision of suction and controls the movement of the
cutter.
34. A biopsy device comprising a cannula with an orifice, the
cannula being configured for insertion into a body to a point such
that the orifice is adjacent to a tissue mass to be biopsied; a
cutter housed within the cannula and configured to move relative to
the orifice to selectively cut tissue from the mass; a pneumatic
cylinder coupled to the cutter for moving the cutter relative to
the orifice, the pneumatic cylinder being controlled by a
controller responsive to back pressure in the cylinder; and a
pneumatic motor coupled to the cutter for rotating the cutter
relative to the orifice.
35. The biopsy device of claim 34, wherein the pneumatic motor
comprises six pneumatic vanes.
36. The biopsy device of claim 34, wherein the controller is a
pneumatic circuit.
37. The biopsy device of claim 34, wherein the controller responds
to a back pressure of approximately 24 pounds per square inch.
38. The biopsy device of claim 34, wherein the controller directs
the cutter to retract relative to the cannula when a predetermined
back pressure is sensed in the pneumatic cylinder.
39. The biopsy device of claim 38, wherein the predetermined back
pressure is approximately 24 pounds per square inch.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Ser. No.
60/374,952 filed Apr. 23, 2002.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to a pneumatic circuit, and
particularly to a pneumatic circuit for use in the operation of an
at least partially air-powered tool. More particularly, the present
invention relates to a pneumatic circuit useful in the pneumatic
operation of a medical device.
SUMMARY OF THE INVENTION
[0003] The present invention relates to one or more of the
following features, elements or combinations thereof. A pneumatic
control system is provided for use with a medical device,
illustratively a suction biopsy device. The suction biopsy device
has a cannula for insertion into a body to a point adjacent to a
mass to be examined, and a rotating cutter device is housed within.
The cannula has an orifice, and a pneumatic cylinder is coupled to
the cutter for moving the cutter relative to the orifice.
[0004] A rinse or illustratively saline solution is provided for
assisting in the removal of the mass to be examined. A suction is
provided for assisting in the removal of the mass to be examined.
The control system has an absence of electrical circuitry
configured to control the operation of the suction biopsy device.
Electrical power is illustratively provided only for the compressor
and the vacuum.
[0005] The cannula defines an axis and the cutter is illustratively
aligned coaxially with the cannula for rotation about the axis. A
pneumatic motor actuates the rotational movement of the cutter. The
pneumatic cylinder causes the cutter to move axially relative to
the cannula.
[0006] A method of removing a tissue mass from a body is also
provided. The method comprises the steps of inserting a hollow
cannula having an aperture into the body such that the aperture is
positioned adjacent to the tissue mass. Suction is provided to the
cannula such that a portion of the tissue mass is pulled inside the
cannula through the aperture. The cutter is pneumatically caused to
move relative to the aperture so that the cutter cuts the portion
of tissue mass from the remainder of the tissue mass. The cut
portion of tissue mass is then transported through the cannula with
the provided suction. The pneumatic movement of the cutter is
controlled by a pneumatic circuit comprising a pressure sensor.
[0007] The control system drives a cutter blade connected to the
biopsy device. The cutter blade moves from a recessed position to
an extended position. The control system cycles the cutter between
the recessed position and the extended position at a predetermined
cycle rate, responding to user commands when determining whether to
continue to cycle.
[0008] A pneumatically driven motor rotates the cutter. A
pneumatically driven piston moves the cutter between the recessed
position and the extended position. Pressurized gas is delivered to
the pneumatic motor, and a saline supply is delivered to the
cannula.
[0009] Suction assists in removing the mass from the body during a
surgical procedure. The control system is configured to run
continually but have cyclical elements responding to the continual
operation.
[0010] Additional features of the disclosure will become apparent
to those skilled in the art upon consideration of the following
detailed description of preferred embodiments exemplifying the best
mode of carrying out the invention as presently perceived.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The detailed description particularly refers to the
accompanying figures in which:
[0012] FIG. 1 is a top perspective partial view of a Breast Biopsy
System having a hand wand, the Biopsy System including a pneumatic
circuit internally, the circuit configured to operate the Biopsy
System and hand wand;
[0013] FIG. 2 is a perspective view of the system shown in FIG.
1;
[0014] FIG. 3A is a view of the cannula of the hand wand inserted
into a patient's breast adjacent a tissue mass, the cannula having
an aperture positioned adjacent the mass;
[0015] FIG. 3B is a view similar to that of FIG. 3A, showing a
cylindrical cutter that has moved inside the cannula, thereby
cutting away a portion of the tissue mass;
[0016] FIG. 4 is a view of an air compressor shown upside down with
tie-down rails and springs attached;
[0017] FIG. 5 is a view of the compressor of FIG. 4, showing the
compressor right side up with additional fittings;
[0018] FIG. 6 is a view of a vacuum pump showing the tie-down rail
and springs;
[0019] FIG. 7 is a view of the compressor of FIGS. 4-5 and the
vacuum pump of FIG. 6 both installed in a console;
[0020] FIG. 8 is a view of a console mounting panel showing
manifold subassemblies, a filter subassembly, and a terminal block
subassembly mounted on the mounting panel;
[0021] FIG. 9 is a view of the console showing the mounting panel
mounted in the console, and showing the cavity in the lower portion
which houses the compressor and vacuum;
[0022] FIG. 10 is a view from the top of the console of FIG. 8;
[0023] FIG. 11 is a view from the front of the open console similar
to that of FIG. 9, showing the compressor and vacuum pump mounted
in the lower portion of the console and showing other components of
the pneumatic circuit mounted in the upper portion of the
console;
[0024] FIGS. 12A-B are views of two embodiments of a water
evaporation subassembly;
[0025] FIGS. 13A-B show, respectively, the foot switch prior to
attachment of tubing, and the foot switch partially assembled after
the attachment of tubing;
[0026] FIG. 14 is a view of the terminal block subassembly;
[0027] FIGS. 15A-B are perspective views of the two manifolds
configured to route the pneumatic tubing within the console;
[0028] FIGS. 16A-B are schematic representations of the pneumatic
circuit elements;
[0029] FIG. 17 is a schematic representation of an evaporation
valve portion of the pneumatic circuit;
[0030] FIG. 18 is another schematic representation of a portion of
the pneumatic circuit;
[0031] FIGS. 19A-D show specification drawings for the console;
[0032] FIG. 20A shows the configuration of the control panel;
[0033] FIG. 20B shows the configuration of the manifolds with
relation to the filters and connection points;
[0034] FIGS. 21A-D show diagrammatic representations of the
manifolds depicting the ports and internal passageways associated
with the manifolds;
[0035] FIG. 22A shows a top view of a pinch valve configured to
control the flow of saline;
[0036] FIG. 22B is a front elevation view of the pinch valve shown
in FIG. 22A, showing the tube positioned in the pinch valve, and
showing the movement of the plunger between a flow position and a
non-flow position;
[0037] FIGS. 23A-D show specification drawings for the gasket;
[0038] FIGS. 24A-B show a top view and a front elevation view,
respectively, of a canister bracket;
[0039] FIGS. 25A-D show front and side views of a pair of hose wrap
pins;
[0040] FIGS. 26A-B show a foot switch holder;
[0041] FIG. 27 shows a valve bracket;
[0042] FIGS. 28A-B show an embodiment of tie-down rails;
[0043] FIGS. 29-33 show the test equipment used in testing certain
elements in the pneumatic circuit in various stages of the test;
and
[0044] FIGS. 34A-C show parts listings of the various parts used in
the construction of the Breast Biopsy System.
DETAILED DESCRIPTION OF THE DRAWINGS
[0045] One embodiment of the present disclosure is shown in FIGS. 1
and 2 in the form of a Breast Biopsy System 2 having a hand wand 4.
Biopsy System 2 illustratively includes a console 6 having an
access door 8 and a control panel 9 positioned toward the top of
the console 6. Biopsy System 2 includes an internal pneumatic
circuit 10 (shown in FIGS. 8-12 and schematically in FIGS. 16-18)
that is configured to operate a medical device 70, illustratively
hand wand 4, as will be discussed in more detail below. It should
be understood that as used herein, medical device 70 can be any
medical device that is powered at least in part by pneumatic
pressure. The illustrative medical device 70 comprises a hand wand
4, and such terms are used interchangeably throughout.
[0046] Biopsy System 2, and particularly hand wand 4,
illustratively function in the following manner. A patient having a
mass 142 to be removed receives a local anesthetic and the mass is
identified and located in the patient. Location methods may include
ultrasound, magnetic resonance imaging (MRI), X-Ray, or any other
method known in the medical industry. As can be seen in FIGS. 1 and
3A-B, hand wand 4 illustratively includes a hollowed needle or
cannula 130 extending therefrom, the cannula 130 having a sharp
distal end 136 for facilitating piercing into the patient's body,
and the cannula 130 further having a cutter 134 positioned therein
for rotational and axial movement relative to the cannula 130.
Cutter 134 is illustratively a cylindrical blade, but other
configurations are within the scope of the disclosure. Distal end
136 is illustratively a frusto-conical stainless steel tip
press-fitted on the end of cannula 130, the tip having a plastic
cutting board (not shown) housed within for receiving cutter 134
when cutter 134 is at its full stroke position.
[0047] An aperture 132 is illustratively formed in the cylindrical
wall of cannula 130 at its distal end. During operation, as shown
in FIGS. 3A-B, a physician inserts cannula 130 into the patient
(i.e. the cannula is inserted into a woman's breast) such that
aperture 132 is positioned proximal to a mass 142 to be removed.
While the cannula is being inserted into the patient's body, the
cylindrical cutter 134 is positioned inside cannula 130 such that
cutter 134 substantially closes off aperture 132. Pneumatic circuit
10 directs compressed air to pneumatic cylinder 26 in order to
position cutter 134 at its full stroke position.
[0048] After cannula 130 is in position in the patient's body,
pneumatic circuit 10 directs the retracting and advancing movement
of cutter 134 relative to the cannula 130 in response to signals
from a foot switch 16, a remote push button 18, or a panel push
button 18A (see FIG. 16B) operated by a medical technician or
surgeon. Once the operator signals for the cutting to begin,
pneumatic circuit 10 directs vacuum pressure to hand wand 4, and
pneumatic circuit releases the compressed air from pneumatic
cylinder 26 (which is illustratively housed in hand wand 4). Once
compressed air is released from pneumatic cylinder 26, a spring
urges the plunger in pneumatic cylinder 26 toward the retracted
position, thereby causing cutter 134 to move to the retracted
position, consequently opening aperture 132. Vacuum pressure is
also applied by pneumatic circuit 10 to the inside of cannula 130,
causing a portion of the mass 142 to be drawn inside cannula 130.
While the portion of the mass 142 is drawn inside cannula 130,
pneumatic circuit 10 sends compressed air to cylinder 26, thereby
moving cutter 134 relative to aperture 132 toward the extended,
full-stroke position. At substantially the same time, pneumatic
circuit 10 further directs compressed air toward a pneumatic motor
138 housed in hand wand 4. Pneumatic motor 138 is coupled to cutter
134 and causes cutter 134 to rotate about its axis inside cannula
130. As a result of the rotational and axial movement of cannula
130, cutter 134 cuts the portion of the mass 142 that extends
inside the cannula 130 as cutter moves toward distal end 136 of
cannula 130.
[0049] Once cutter 134 has completed such a cycle and has returned
to the position wherein aperture 132 is closed, pneumatic circuit
10 confirms whether further cutting will be necessary. Such
confirmation is received from foot switch 16 or remote push button
18/panel push button 18A, described further herein. In the
illustrated embodiment, a short pause of approximately a half
second prior to confirmation allows sufficient time for an operator
to determine whether additional cutting will be necessary.
[0050] If additional cutting is not deemed to be required and the
mass 142 is considered removed, the operator removes cannula 130
from the patient's body. If instead confirmation is made that
additional cutting is required, pneumatic cylinder 26 causes cutter
134 to again move to the retracted position, thereby opening the
aperture 132, and saline is directed through the hand wand 4 and
between cannula 130 and cutter 134. Saline passing over the cutting
end 140 of cutter 134 is suctioned into the central portion of the
cannula 130 with urging from the aforementioned applied vacuum
pressure. Suctioning saline through the central portion of cannula
130 serves to flush the cut portion of the mass through the cannula
toward a waste canister 28, described further herein. Additionally,
the saline serves as a lubricant between the cannula 130 and the
cutter 134. In the illustrative embodiment, pneumatic motor 138 is
not actuated while cutter 134 is moved toward the retracted
position, therefore cutter 134 does not rotate relative to cannula
130 during this retraction phase. Such operation is desirable so
that tissue does not wrap around cutter 134 as cutter 134
retracts.
[0051] Pneumatic circuit 10 directs the continuous above-described
cycling of cutter 134 as long as foot switch 16 or remote push
button 18 or panel push button 18A is depressed. Illustratively,
ultrasound, magnetic resonance imaging (MRI), or other
mass-locating methods known in the art may be used during the
procedure in order to monitor the progress of the removal of the
mass 142. It is advantageous that Breast Biopsy System 2, in one
embodiment, can be used in conjunction with an MRI device because
of the majority of its components being pneumatic and
non-magnetic.
[0052] The components comprising pneumatic circuit 10, and their
associated functions in the control of hand wand 4, are described
below. FIGS. 4 and 5 show views of an air compressor 11 having
tie-down rails 13 and springs 15 attached thereto. Fittings 17 are
coupled to the top of air compressor 11 as shown in FIG. 5, and air
compressor 11 is illustratively mounted in the rear of the console
6 as shown in FIG. 7.
[0053] A vacuum pump 19 is shown in FIG. 6, the vacuum pump having
a tie-down rail 21 and springs 23. FIG. 7 shows the relative
placement of vacuum pump 19 and air compressor 11 in the lower
portion of console 6. Soundproofing material 37 is also placed in
the proximity of vacuum pump 19 and air compressor 11 in order to
muffle the sound of air compressor 11 and vacuum pump 19 during
operation.
[0054] FIG. 8 is a view of a console mounting panel 25 showing
manifold subassemblies 27, 29, an evaporation subassembly 31, and a
terminal block subassembly 33 mounted on the mounting panel 25.
FIGS. 9 and 10 show the console mounting panel 25 mounted in the
console 6. Compressor 11 and vacuum pump 19 are not installed in
the illustrative FIGS. 9 and 10.
[0055] Console 6 is shown in FIG. 11 to have compressor 11 and
vacuum pump 19 mounted in the console 6 while other components of
pneumatic circuit 10 including console mounting panel 25 are
mounted in the upper portion of console 6. Shelf 35 is mounted to
divide console mounting panel 25 from compressor 11 and vacuum pump
19. As noted above, soundproofing material 37 is positioned to
surround compressor 11 and vacuum pump 19.
[0056] FIG. 12A shows water evaporation subassembly 31 prior to
installation in pneumatic circuit 10. Water evaporation subassembly
31 includes a filter 41, relief regulator 43, and gas-permeable
absorber 45. Filter 41 is configured to direct condensation toward
gas-permeable absorber 45, which in turn dissipates the
condensation into the atmosphere. The schematic representation of
water evaporation subassembly 31 can be seen in FIG. 17.
[0057] FIG. 12B is an alternative embodiment 31' of the water
evaporation subassembly 31 of FIG. 12A. In alternative embodiment
31', conduits and fitting of subassembly 31 are replaced with
manifolds 34, 36. Manifolds 34, 36 act as conduits and as fitting
receivers for components such as filter 41, relief regulator 43,
and gas-permeable absorber 45.
[0058] FIGS. 13A and 13B show the assembly of foot switch 16 prior
to and after the attachment of tubing. FIG. 14 is a view of the
terminal block subassembly 33 prior to installation on the console
mounting panel 25, shown in FIG. 8. The terminal block subassembly
33 functions to distribute electrical power to the compressor 11,
vacuum pump 19, and dump valves.
[0059] Custom designed manifolds 47, 49 can be seen in perspective
view in FIGS. 15A-B. Manifolds 47, 49 are configured to route the
pneumatic tubing (not shown in FIGS. 15A-B, but viewable in FIG. 8)
within the console. Schematics for manifolds 47, 49 can be seen in
FIGS. 20B and 21A-D.
[0060] FIGS. 16A-B illustrate the schematic of the illustrative
pneumatic circuit 10. Pneumatic circuit 10 includes a first
sequence loop 12 (approximated as the elements within the broken
lines) and a second sequence loop 14 (outside the broken lines).
First sequence loop 12 is initiated with either a foot switch 16, a
remote pushbutton 18, or a panel pushbutton 18A. Foot switch 16 is
the illustrated embodiment in the drawings, however, any of the
above foot switch 16, a remote pushbutton 18, or a panel pushbutton
18A, including combinations thereof, are within the scope of the
disclosure.
[0061] Sensor 20 (shown in FIG. 16B) senses pressurization and
permits passage of pressurized gas through path 22 when foot switch
16, pushbutton 18, or pushbutton 18A is actuated, or any
combination thereof. The pressurized gas shifts the vacuum valve 48
(FIG. 16A), creating vacuum in collection canister 28. Vacuum
sensor 30 passes a signal to the vacuum indicator 150 when the
vacuum level reaches 20" Hg vacuum. Pressurized signals from
components 30, 22 pass through the "and" gate 50 (FIG. 16A) and
latch relay 24, which in turn signals cutter cylinder 26 to retract
to a non-extended position. When cutter cylinder 26 is retracted
into the non-extended position, pressurized gas is delivered to
medical device 70, illustratively to operate pneumatic motor 138.
However, it should be understood that pressurized gas may be
utilized for any number of functions in a medical device, and is
not restricted to the illustrative functions shown in hand wand
4.
[0062] A saline supply 152 (FIG. 16B) is also illustratively
provided to medical device 70, the saline supply 152 fostering the
flow of biological material removed by the medical device 70 to
collection canister 28. Pinch valve 72, which includes
pneumatically actuated stopper 88 (FIG. 16B), controls the flow of
saline supply 152 in a manner described further herein.
[0063] Collection canister 28 collects biological material from the
medical device 70 during the medical procedure using vacuum
pressure. In addition to the biological material being collected,
saline is collected in this manner. If the vacuum pressure fails,
such failure is sensed by vacuum switch 30, and the cycle stops.
Otherwise, pressurized gas continues to be delivered for a period
of time determined by timing circuit 148.
[0064] Timing circuit 148 incorporates a restricted orifice that
fills volume chamber 144 with gas and eventually signals valve 146
to turn on the pressurized gas to medical device 70. Pressurized
gas causes cutter cylinder 26 to advance at a rate controlled by
timing circuit 38 until it reaches the extended position (also the
position held during insertion of the cannula of the illustrative
medical device, described above). Such pressurized gas continues to
build up in medical device 70 until pressure sensor 52 senses a
predetermined gas pressure in cutter cylinder 26 and illustratively
trips at approximately 24 psi, indicating the end of the stroke. At
such a point, signaling device 54 causes a momentary audible
signal, and also latch relay 24 resets, turning off device 70. If
signal 22 is still present, the relay 24 will not reset and the
process will automatically repeat. If the process repeats the
audible tone has a shorter duration than if it resets.
[0065] It is also possible that cutter cylinder 26 does not fully
advance to the extended position before pressure sensor 52 trips.
In such an instance, cutter cylinder 26 may encounter difficulties
cutting through the mass 142, and pressure will build up in cutter
cylinder 26 even though the end of the stroke has not been reached.
When the cylinder pressure reaches the predetermined amount of 24
psi, sensor 52 trips, regardless of the position of cutter cylinder
26 (and the attached cutter 134).
[0066] Setup switch 44 (FIG. 16B), which is controlled by knob 154
on control panel 9 (FIG. 1) allows an operator to load the saline
tube into the pinch valve 72 and primes the medical device by
actuating, in parallel, the retraction of cutter cylinder 26, the
opening of saline pinch valve 72, and the opening of vacuum valve
48. During this setup mode, signals from 22 are ignored, thereby
inhibiting a cycle start condition. Aspiration switch 40 (FIG.
16B), which is controlled by knob 156 on control panel 9 (FIG. 1)
inhibits a cycle start condition and causes cylinder 26 to retract,
if a signal delivered via path 22 is present the vacuum valve 48
shifts creating vacuum in the canister and the medical device.
[0067] Referring to FIGS. 16A-B, pneumatic circuit 10 operates in
substantially the following fashion. Air compressor 11 is turned on
and creates air pressure and flow. The compression process creates
heat and condenses the humidity in the air. At such a point,
condensed water is in gaseous state. The hot moist air is then
passed through a fan-driven air-to-air heat exchanger 158 cooling
the air and changing the water to a liquid state. The cooled air is
then passed into a coalescing filter 41 where the water is captured
in the filter media and drips into the bottom of the filter bowl.
The filtered air then continues out to feed the control
circuit.
[0068] The compressor runs continuously. If pressure is sensed by
the relief regulator of greater than the set point of 70 psi, it
will continuously vent the excess pressure. If the system is on and
not in cycle, 99% of the compressor flow rate will vent out of the
relief regulator. While the system is cycling the medical device,
approximately 40% of the system capability will continuously flow
through the relief regulator.
[0069] The water that is collected in the bottom of the filter bowl
is dissipated with water evaporation subassembly 39. Water passes
from the filter 41 through the relief regulator 43 and into the
base of the permeable exhaust member 45. The exhaust member 45 acts
as a wick, drawing the fluid up the media. The flow rate through
the exhaust member 45 and the large "wick" surface area cause the
liquid water to evaporate into a gas state. The flow rate through
the enclosure caused by the heat exchanger fans removes the water
vapor from the cabinet, thus eliminating the need to collect water
and drain it from the system. Illustratively, a filter "muffler" is
used as a permeable exhaust member 45, the muffler being available
from Allied Witan Company, of Cleveland, Ohio, as part number
F02.
[0070] The pneumatic circuit components are mounted to custom
aluminum manifolds 47, 49 minimizing the use of fittings and
keeping the system compact. The components are "sub-base" style
versions of the component allowing for ease of replacement. Each
component that needs adjusted is bench tested and set to the
specified level using certified fixtures. Diagrammatic
representations of the manifolds can be seen in FIGS. 21A-D.
[0071] Console 6 is designed to isolate the noise and heat created
by compressor 11 and vacuum pump 19. Design specifications for
console 6 can be seen in FIGS. 19A-D. Shelf 35 divides the cabinet
into two sections. The lower section contains the spring-mounted
pumps 11, 19, soundproofing material 37, and fans to isolate
vibration, heat, and noise, as can be seen in FIG. 7.
[0072] As shown in various views in FIGS. 22A-B, pinch valve 72
includes a retainer comprised of a central catch 74 and opposing
catches 76, 78. See also a view of pinch valve 72 in FIG. 1.
Silicone tubing 80 is bent into a configuration as shown in broken
lines, and pushed between central catch 74 and opposing catches 76,
78. When pulled taut, silicone tubing 80 assumes a substantially
straight configuration and is disposed under cantilevered portion
82 of central catch 74, and cantilevered portions 84, 86 of
opposing catches 76, 78 respectively, as shown in FIG. 22A. Such a
configuration secures the silicone tubing 80 and prevents
accidental removal of silicone tubing 80 from pinch valve 72.
[0073] Pneumatically actuated stopper 88, shown diagrammatically in
FIG. 22B, moves a piston 90 between a stopped position (shown in
broken lines) and a flow position. The default position is the
stopped position, stopping the flow of fluid through the silicone
tubing 80.
[0074] FIGS. 25A-D show a pair of hose wrap pins that is used to
wrap the foot switch tube set and the power cord when the system is
not in use. FIGS. 26A-B show a foot switch holder. FIG. 27 shows a
valve bracket. And FIGS. 28A-B show an embodiment of tie-down
rails.
[0075] The test module 92 for testing Airtrol electric pressure
switch 120 (as shown in FIGS. 11 and 16A), model number
F-4200-60-MM, can be seen in FIGS. 29-33. The switch 120 is placed
on test module 92 and clamped in place, as seen in FIG. 29. A red
jumper 94 is connected to the normally open (N.O.) terminal 98 of
switch 120. Black jumper 96 is connected to COM terminal 100. A
plugged union fitting 102 is connected to an end of natural colored
tube 104. With an air supply to test module 92 turned on,
2-position detented button 122 is pulled out and pressure observed.
It is further observed when green indicator light 106 turns on. If
green indicator light 106 does not turn on at 20 psi+/-0.5 psi,
then button 122 should be pushed back in and adjustments made to
switch 120, and testing done again. After the proper target
pressure is obtained, a green dot sticker 108 is placed over the
adjustment screw. Pneumatic vacuum switch VP-701-30-MM is tested in
a similar fashion, with a targeted setting of 20" Hg vacuum.
[0076] Another test procedure for test module 92 is shown in FIGS.
30 and 31. In such a procedure, Airtrol pneumatic pressure switch
120' (model number PP-701-30-MM) is tested. Red tube 109 is
connected to output port 110. Natural tube 104 is connected to
input port 112. With an air supply to test module 92 turned on,
button 122 is pulled out and pressure at which large green light
114 comes on is observed. If large green light 114 does not turn on
at 24 psi+/-0.5 psi, then button 122 should be pushed back in and
adjustments made to switch 120', and testing done again. After the
proper target pressure is obtained, a green dot sticker 108 is
placed over the adjustment screw.
[0077] Yet another test module 92' for testing various regulators
is shown in FIGS. 32 and 33. This test module 92' is illustratively
used for the cutter cylinder regulator 124 (model R4, R01-10 w/60
psi gauge), the air motor regulator 126 (model R2, R01-12 w/60 psi
gauge), and the main regulator 128 (model R1, R01-12 w/160 psi
gauge). The regulators are illustrated schematically in FIGS.
16A-B, and on diagrammatic views of the manifolds in FIGS. 20B and
21A-B. During testing, the tested regulator 124, 126, 128 should be
set for the appropriate target pressure (60 psi, 60 psi, and 160
psi, respectively). Next, two O-rings 116 (seen in FIG. 32) should
be installed in the bottom of the tested regulator. The regulator
124, 126, 128 is then placed on the test module 92' aligning the
locating pin and locating hole found on the test module and
regulator. Regulator 124, 126, 128 is then clamped in place.
[0078] Target pressures during testing of regulators 124, 126, 128
varies depending on the regulator. Model R4 is targeted for 30 psi,
rising. Model R2 is targeted for 40 psi, rising. Model R1 is
targeted for 60 psi, rising. Once pressure is dialed in to the
appropriate target, the regulator nut is tightened to prevent knob
movement and a permanent marker is used to mark the cannula
position of the regulator gauge. Finally, a green dot is placed in
the center of the gauge face.
[0079] Illustrative parts used in the production of the
above-described embodiment can be found in FIGS. 34A-C. It should
be understood, however, that other parts and constructions are
within the scope of the disclosure.
[0080] While the disclosure is susceptible to various modifications
and alternative forms, specific exemplary embodiments thereof have
been shown by way of example in the drawings and have herein been
described in detail. It should be understood, however, that there
is no intent to limit the disclosure to the particular forms
disclosed, but on the contrary, the intention is to cover all
modifications, equivalents, and alternatives falling within the
spirit and scope of the disclosure as defined by the appended
claims.
[0081] A plurality of advantages arises from the various features
of the present disclosure. It will be noted that alternative
embodiments of various components of the disclosure may not include
all of the features described yet still benefit from at least some
of the advantages of such features. Those of ordinary skill in the
art may readily devise their own implementations of a pneumatic
circuit that incorporate one or more of the features of the present
disclosure and fall within the spirit and scope of the
disclosure.
* * * * *