U.S. patent application number 11/563504 was filed with the patent office on 2007-06-28 for medical/surgical irrigator with a tip through which irrigation fluid is discharged and a suction is drawn, a variable rate pulse pump for discharging the irrigation fluid and a seperate battery pack for powering the pump.
Invention is credited to Jeffery D. Arnett, Nicholas V. Gately, David H. Grulke, Ruth A. Hilsbos, James L. Sertic.
Application Number | 20070149918 11/563504 |
Document ID | / |
Family ID | 32329685 |
Filed Date | 2007-06-28 |
United States Patent
Application |
20070149918 |
Kind Code |
A1 |
Arnett; Jeffery D. ; et
al. |
June 28, 2007 |
MEDICAL/SURGICAL IRRIGATOR WITH A TIP THROUGH WHICH IRRIGATION
FLUID IS DISCHARGED AND A SUCTION IS DRAWN, A VARIABLE RATE PULSE
PUMP FOR DISCHARGING THE IRRIGATION FLUID AND A SEPERATE BATTERY
PACK FOR POWERING THE PUMP
Abstract
A medical/surgical irrigator comprising a handpiece and a tip
assembly that is removably attached to the handpiece. Internal to
the handpiece is a variable speed pulse pump from which irrigation
fluid is discharged through the tip assembly. A single, variable
speed motor regulates the pumping rate of the pump. The tip
assembly includes a suction wand through which the discharged fluid
is drawn away from the site to which the fluid is applied.
Inventors: |
Arnett; Jeffery D.;
(Kalamazoo, MI) ; Gately; Nicholas V.; (Portage,
MI) ; Grulke; David H.; (Battle Creek, MI) ;
Hilsbos; Ruth A.; (Saline, MI) ; Sertic; James
L.; (Kalamazoo, MI) |
Correspondence
Address: |
INTEL. PROP./ RND;STRYKER CORPORATION
4100 EAST MILHAM AVE.
KALMAZOO
MI
49001-6197
US
|
Family ID: |
32329685 |
Appl. No.: |
11/563504 |
Filed: |
November 27, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10838890 |
May 4, 2004 |
7144383 |
|
|
11563504 |
Nov 27, 2006 |
|
|
|
09460705 |
Dec 14, 1999 |
6746419 |
|
|
10838890 |
May 4, 2004 |
|
|
|
09009657 |
Jan 20, 1998 |
6022329 |
|
|
09460705 |
Dec 14, 1999 |
|
|
|
08559133 |
Nov 17, 1995 |
5718668 |
|
|
09009657 |
Jan 20, 1998 |
|
|
|
08049144 |
Apr 19, 1993 |
5470305 |
|
|
08559133 |
Nov 17, 1995 |
|
|
|
Current U.S.
Class: |
604/35 ; 601/155;
601/159; 601/161; 604/153; 604/246; 604/902 |
Current CPC
Class: |
A61M 1/0037 20130101;
Y10S 604/902 20130101; A61M 1/0064 20130101; A61M 1/0072 20140204;
A61M 3/0208 20140204; A61M 2205/8206 20130101; A61M 3/022 20140204;
A61M 3/025 20130101; A61M 3/0258 20130101 |
Class at
Publication: |
604/035 ;
604/153; 604/246; 604/902; 601/155; 601/159; 601/161 |
International
Class: |
A61M 1/00 20060101
A61M001/00 |
Claims
1-30. (canceled)
31. A medical irrigator comprising: a housing shaped to be hand
held and having a front end, the front end having a fluid outlet
opening; a tip assembly that extends forward from the front end of
said housing, said tip assembly having an outlet tube in fluid
communication with the housing fluid outlet opening and a suction
tube; an inlet tube extending to said housing; a pulse pump capable
of operating at a variable rate disposed in said housing that opens
to the housing front end, said pump configured to receive fluid
from said inlet tube and discharging the fluid through the fluid
outlet opening; a single electric motor disposed in said housing
and connected to said pump for actuating said pump, said motor
operable at variable speeds to control the pumping rate of said
pump; a control assembly disposed in said housing to regulate the
speed of said motor; a flexible suction tube that is in fluid
communication with said tip assembly suction tube and that extends
away from said housing; a battery pack separate from said housing;
and a flexible conductor assembly extending from said battery pack
to said housing for supplying energy stored in said battery pack to
said motor.
32. The medical irrigator of claim 31, wherein said control
assembly has a switch that is moveably mounted to said housing,
said control assembly configured so that: when said switch is in a
first position, said control assembly does not supply an
energization signal to said motor; when said switch is in a second
position, said control assembly supplies a first energization
signal from said battery pack to said motor; and when said switch
is in a third position, said control assembly supplies a second
energization signal from said battery pack to said motor.
33. The medical irrigator of claim 31, wherein said switch is
configured to move: from the first position and to the second
position; and from the second position to the third position.
34. The medical irrigator of claim 31, wherein: said housing is
formed to have: a handle; and a barrel integral with and located
above said handle that extends forward from said handle, said
barrel having the housing front end; and said motor is located in
said housing handle.
35. The medical irrigator of claim 31, wherein said tip assembly
outlet tube surrounds said tip assembly inlet tube.
36. The medical irrigator of claim 31, wherein said inlet tube
extends from said battery pack to said housing.
37. The medical irrigator of claim 31 wherein: the housing front
end is formed with a fluid inlet opening; said tip assembly inlet
tube is connected to the housing fluid inlet opening; a suction
hose disposed in said housing extends from the housing fluid inlet
opening and said flexible suction tube is connected to said suction
hose.
38. The medical irrigator of claim 31, wherein said housing and
said tip assembly are formed with complementary features for
releasably holding said tip assembly to the housing front end.
39. A medical irrigator comprising: a housing shaped to have a
front end; a pulse discharge pump that operates at a variable rate
disposed in said housing having an inlet and discharge conduit, the
discharge conduit opening towards the front end of said housing; an
inlet line that extends into said housing that is in fluid
communication with the pump inlet; a single electric motor disposed
in said housing and connected to said pump to actuate said pump,
said motor operating at variable speeds to regulate the pumping
rate of said pump; a tip assembly that extends from the front end
of said housing, said tip assembly having an outlet tube that is in
fluid communication with the pump discharge conduit and a suction
wand; a flexible suction tube that is in fluid communication with
said tip assembly suction wand; a battery pack separate and spaced
from said housing that contains at least one battery that stores
energy for energizing said motor; a flexible cable that extends
from said battery pack to said housing for supplying energy from
said battery pack to said motor; and a control assembly integral
with said housing, said control assembly having a switch member
moveably mounted to said housing and said control assembly being
configured to apply a variable energization signal from said
battery pack to said motor so as to control the speed of said motor
and regulate the pumping rate of said pump.
40. The medical irrigator of claim 39, wherein: said cable includes
a first conductor over which a first energization signal is
available from said battery pack and a second conductor over which
a second energization signal is available from said battery pack;
and said control assembly is configured so that switch member can
be selectively positioned to: connect neither of said cable
conductors to said motor; connect the first said cable conductor to
said motor; or connect the second said cable conductor to said
motor.
41. The medical irrigator of claim 40, wherein said control
assembly is configured to sequentially move from the position in
which neither said cable conductors are connected to said motor to
the position in which said first cable conductor is connected to
said motor and to the position in which the second said cable
conductor is connected to said motor.
42. The medical irrigator of claim 39, wherein said pump is a
reciprocating pump.
43. The medical irrigator of claim 39, wherein said inlet line
extends from said battery pack to said housing.
44. The medical irrigator of claim 39, wherein said tip assembly is
constructed so that said outlet tube is disposed in said suction
wand.
45. The medical irrigator of claim 39, wherein: a suction hose
having opposed ends is disposed in said housing; said suction wand
is connected to a first end of said suction hose; and said flexible
suction tube is connected to a second end of said suction hose.
46. A medical irrigator, said irrigator comprising: a housing
having a front face; a tip assembly that extends from the front
face of said housing, said tip assembly including an outlet tube
and a suction wand; a pulse discharge pump disposed in said housing
that operates at a variable rate, said pump having an inlet and an
outlet, the outlet opening into the front face of said housing so
as to be in fluid communication with said tip assembly outlet tube;
a flexible suction tube that is in fluid communication with said
tip assembly suction wand, said flexible suction tube extending
away from said tip assembly; a single, variable speed electric
motor disposed in said housing connected to said pump for actuating
said pump at variable rates; a battery pack separate from said
housing containing at least one battery; a flexible cable that
extends from said battery pack to said housing, said flexible cable
having at least one conductor over which an energization signal
from said at least one battery is supplied; and a control assembly
attached to said housing and connected between said at least one
conductor and said motor for supplying a variable potential
energization signal to said motor, said control assembly having a
single switch member that is moveably attached to said housing that
selectively makes/breaks a connection between said at least one
conductor and said motor and that establishes the potential of the
energization signal supplied to said motor.
47. The medical irrigator of claim 46, wherein: said cable has a
first conductor over which a first energization signal is available
from said at least one battery and a second conductor over which a
second energization signal is available from said at least one
battery; and said control assembly is configured so that switch
member can be selectively positioned to: connect neither of said
cable conductors to said motor; connect the first said cable
conductor to said motor; or connect the second said cable conductor
to said motor.
48. The medical irrigator of claim 47, wherein said control
assembly has a first contact to which said first cable conductor is
attached and a second contact to which said second cable conductor
is attached and said contacts are statically mounted to said
housing.
49. The medical irrigator of claim 46, wherein: the housing front
face is formed with a fluid inlet opening in which said tip
assembly suction wand is received; a suction hose is disposed in
said housing and extends from the fluid inlet opening; and said
suction tube is connected to said suction hose.
50. The medical irrigator of claim 46, wherein said tip assembly is
constructed so that said outlet tube is disposed in said suction
wand.
Description
[0001] This application is a continuation of U.S. patent
application Ser. No. 10/838,890 filed 4 May 2004, now U.S. Pat. No.
7,144,383, which is a continuation of U.S. patent application Ser.
No. 09/460,705 filed 14 Dec. 1999, now U.S. Pat. No. 6,746,419,
which is a continuation of U.S. patent application Ser. No.
09/009,657, filed 20 Jan. 1998, now U.S. Pat. No. 6,022,329, which
is a continuation of U.S. patent application Ser. No. 08/559,133,
filed 17 Nov. 1995, now U.S. Pat. No. 5,718,668, which is a
continuation of U.S. patent application Ser. No. 08/049,144, filed
19 Apr. 1993, now U.S. Pat. No. 5,470,305.
FIELD OF THE INVENTION
[0002] This invention relates to a surgical irrigation with a built
in pulsing pump.
BACKGROUND OF THE INVENTION
[0003] Grulke et al U.S. Pat. No. 5,046,486, assigned to the
Assignee of the present invention, discloses a surgical pulsed
irrigation handpiece which produces a pulsed irrigation liquid
output capable of loosening and floating debris at a surgical site
for subsequent removal (as by suction). This prior pulsed
irrigation handpiece has been on the market for several years and
has proved generally effective for its intended use and hence has
been popular in the surgical community.
[0004] However, in a continuing effort to improve on existing
devices of this general kind, the present invention has been
developed. As compared to the above-mentioned prior device, a
pulsed irrigation handpiece embodying the present invention is
producible at lower cost, produces sharper liquid pulse transients
(particularly the pulse "off" transient), requires no connection to
any operating room power source (e.g. compressed air) or to an
external pump, and instead is self-contained, requires only
external connection to a irrigation liquid source (e.g.
conventional irrigation liquid bag), provides better suction (when
suction is required), is more compact, and is conveniently shaped
to be held either as a pistol or a wand (by the handle or
barrel).
[0005] Other objects, purposes and advantages of the invention will
be apparent to those acquainted with apparatus as general kind upon
reading the following description and inspecting the accompanying
drawings.
SUMMARY OF THE INVENTION
[0006] A pulsed irrigation handpiece comprises pulsed irrigation
liquid outlet means for applying liquid pulses to a surgical site,
pump means reciprocatingly drivable for pumping pulses of
irrigation liquid through said outlet means, powered drive means
for reciprocatingly driving said pump means and housing means
containing said pump means and drive means.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a pictorial view of a handpiece embodying the
invention.
[0008] FIG. 2 is a laterally exploded pictorial view of the FIG. 1
handpiece.
[0009] FIG. 3 is an enlarged elevational view of the FIG. 1
handpiece with the leftward housing part removed.
[0010] FIG. 4 is a view similar to FIG. 3 but with the suction hose
removed, the left drive unit shell part removed and the drive unit
exposed in central cross-section, such that FIG. 4 approximates a
central cross-sectional view of the FIG. 1 handpiece.
[0011] FIG. 4A is an enlarged fragment of FIG. 4 detailing the
rearward portion of the handle.
[0012] FIG. 4B is an enlarged fragmentary pictorial view, taken
from the front, of the electrical contact support posts seen in
FIG. 4A.
[0013] FIG. 4C is an enlarged fragmentary exploded pictorial view
of the electrical contacts, associated with the FIG. 4B posts and
associated electrical conductors from the battery supply.
[0014] FIG. 5 is an enlarged, exploded, pictorial view of the drive
unit of FIG. 2.
[0015] FIG. 6 is a sectional view substantially taken on the line
6-6 of FIG. 5, and provides a top view of the bottom drive unit
shell part of FIG. 5 (the rightward one of FIG. 2) with the drive
components removed to show the interior configuration of that shell
part.
[0016] FIG. 7 is a sectional view substantially taken on the line
7-7 of FIG. 5, and provides a view similar to FIG. 6 but showing
the interior configuration of the other drive unit shell part (the
upper one in FIG. 5 and leftward one in FIG. 2).
[0017] FIG. 8 is an enlarged central cross-sectional view of a tip
unit usable with the handpiece of FIG. 2 and showing same installed
in a pump unit shown in central cross-section substantially as in
FIG. 4.
[0018] FIG. 8A is a reduced size, fragmentary, side elevational
view of the apparatus of FIG. 8.
[0019] FIG. 8B is a pictorial view of the apparatus of FIG. 8A.
[0020] FIG. 9 is an end elevational view of the drive unit, taken
from the right end in FIGS. 2 and 3.
[0021] FIG. 10 is a sectional view substantially taken on the line
10-10 of FIG. 5 and showing the drive unit with one shell part (the
left one in FIG. 2 and top one in FIG. 5) removed to show the motor
and transmission.
[0022] FIG. 11 is an elevational view of the drive train
substantially taken on the line 11-11 of FIG. 10.
[0023] FIG. 12 is a central cross-sectional view substantially
taken on the line 12-12 of FIG. 10.
[0024] FIG. 13 is a fragmentary cross-sectional view substantially
taken on the line 13-13 of FIG. 10.
[0025] FIG. 14 is a cross-sectional view substantially taken on the
line 14-14 of FIG. 10.
[0026] FIG. 15 is a sectional view substantially taken on the line
15-15 of FIG. 10.
[0027] FIG. 16 is an exploded pictorial view of the pump unit of
FIG. 2 in an enlarged scale.
[0028] FIG. 17 is a front end elevational view of the pump unit of
FIG. 16 taken substantially from the left side of FIGS. 2-4 and
16.
[0029] FIG. 18 is a central cross-sectional view of the pump unit
of FIG. 17 taken substantially on the line 18-18 of FIG. 17.
[0030] FIG. 18A is a fragment of FIG. 18 showing the pump unit at
the beginning of an intake stroke.
[0031] FIG. 18B is a fragment of FIG. 18 showing the pump nearing
the end of an output pulse.
[0032] FIG. 18C is a fragmentary enlargement of FIG. 18 showing the
valve member.
[0033] FIG. 19 is a fragmentary cross-sectional view showing the
connection of the pump unit to the liquid supply hose.
[0034] FIG. 20 is a pictorial view of the electric power supply
unit connected to the FIG. 2 handpiece.
[0035] FIG. 21 is a left end view of the FIG. 20 electric power
supply unit.
[0036] FIG. 22 is an exploded pictorial view of the electric power
supply unit of FIG. 20.
[0037] FIG. 22A is an electrical schematic of the FIG. 2 handpiece
and FIG. 20 electric power supply unit.
[0038] FIG. 23 is a central cross-sectional view taken
substantially on the line 23-23 of FIG. 22.
[0039] FIG. 23A is an enlarged fragmentary pictorial view of the
support structure for battery contacts at the forward (left in FIG.
23) end of the electric power supply casing.
[0040] FIG. 23B is an enlarged pictorial view similar to FIG. 23A
but showing the support structure for battery contacts at the
rearward (rightward in FIG. 23) end of the power supply casing.
[0041] FIG. 24 is a sectional view substantially taken on the line
24-24 of FIG. 22 and showing the electric power supply unit with
its top cover removed.
[0042] FIG. 25 is a sectional view substantially taken on the line
25-25 of FIG. 22 and showing the underside of the cover of the
power supply casing.
[0043] FIGS. 26, 27 and 28 are enlarged pictorial views of battery
contacts of FIG. 22.
[0044] FIG. 29 is an enlarged fragmentary pictorial view of an
embodiment of the liquid supply and electric wiring harness of the
apparatus of FIGS. 2 and 20 but showing a modification in the
attachment of the electrical and liquid handling components.
[0045] In the following detailed discussion the terms "up", "down",
"right" and "left", and variations thereon, refer to structural
elements in their positions in specified drawing figures.
DETAILED DESCRIPTION
[0046] A pulsed irrigation handpiece 10 (FIGS. 1 and 2) embodying
the invention comprises a hand-held housing 11 having a handle 12
and a barrel 13 which extends forward from the upper end of the
handle 12 at about a 130.degree. to 150.degree.. (here about
145.degree.) angle thereto.
[0047] The housing 11 is hollow and, for convenience in assembling
the handpiece 10, is constructed as laterally opposed concave left
and right housing parts 14 and 15 (FIG. 2). The housing parts 14
and 15 are preferably molded rigid plastic elements held together
rigidly by any convenient means, here comprising undercut snap fit
tabs 16 protruding from the top and bottom edges of the right
housing part 15 to snap over an interior edge flange (not shown) on
the top and bottom edge of the left housing part 14. If desired,
precise registry together of the two housing parts can be assisted
by laterally projecting pins 20 distributed along the edges of one
housing part (here the left housing part 14) piloted in holes 21
(FIG. 4) in the opposed edges of the other housing part (here 15).
Upon completion of assembly of the handpiece 10, the two housing
parts 14 and 15 may be adhesively bonded together. The handpiece is
intended to be a disposable item and therefore access to the
interior of the housing for purposes of repair is not needed.
Drive Unit
[0048] The drive unit 25 (FIGS. 2-15) is self contained in its own
shell 26 (FIG. 2). For convenience in assembly, the shell 26
comprises two opposed concave shell parts 30 and 31 respectively
disposed to the left and right in FIG. 2. The shell parts 30 and 31
are preferably of rigid molded plastics material. When the drive
unit 25 has been assembled, as in FIGS. 2 and 9, the shell parts 30
and 31 are held fixedly together by any convenient means, here by
resilient snap connection of generally U-shaped clips 32, molded in
spaced relation along the perimeter edge of the shell part 31 which
overlap the perimeter edge of the shell part 30 and snap over tabs
33 protruding therefrom, as seen in FIGS. 5-7. Precise location of
the shell parts 30 and 31 with respect to each other is assisted by
locator pins 34 fixedly protruding from the shell part 31 and holes
35 in the opposed portions of the shell part 30.
[0049] A single conventional DC energizable electric motor 36
(FIGS. 4 and 5) is snugly housed in the space between the left and
right (FIG. 2) shell parts 30 and 31 at the rear (left in FIGS.
5-7, 10 and 12) thereof. The motor 36 is snugly axially located
between the rear end wall 40 and a transverse internal bulkhead 41
of the shell 26 (FIGS. 5-7, 10 and 12). The rear end wall 40 and
bulkhead 41 have opposed parts in the left and right shell parts 30
and 31, as seen in FIGS. 6 and 7.
[0050] Rear and front bosses 42 and 43 respectively extend rearward
and forward from the cylindrical casing 44 of the motor 36, as seen
in FIGS. 10 and 12), and are supported in corresponding coaxial
recesses 45 and 46 in the rear end wall 40 and bulkhead 41
respectively, so as to support the motor casing 44 with respect to
the shell 26. A flat 47 on the rear boss 42 (FIG. 9) co-acts with a
corresponding flat in the surrounding recess 45 to prevent rotation
of the motor casing 44 with respect to the shell parts 30 and 31,
such that the motor 36 is antirotationally fixed within the shell
26.
[0051] The drive unit 25 further includes a transmission 50 (FIG.
5) coaxial with and forward of the motor 36. The transmission
includes a reciprocating link member 51 and is driven from the
forward extending, rotating output shaft 52 of the motor 36. The
shaft 52 extends coaxially forward through the front boss 43 (FIG.
12) of the motor 36.
[0052] The transmission 50 (FIGS. 5 and 12) includes a pinion gear
53 fixed on the motor shaft 52 for rotation thereby, and a face
gear 54 which, as seen in FIG. 12, underlies the pinion gear 53.
The face gear 54 has a relatively large diameter central disk 56
carrying upward facing teeth 55 engaging corresponding teeth on the
pinion gear 53 for rotation thereby. The face gear 54 includes a
secondary pinion gear 57 fixed coaxially beneath the disk 56, and
of substantially lesser diameter, which in turn drives a relatively
large diameter output gear 60.
[0053] It will be understood that the pinion gear 53, face gear 54,
secondary pinion 57 and output gear 60 are all provided with a full
circumferential (360.degree.) set of teeth, so that continuous
rotation of the motor shaft 52 results in continuous rotation of
the output gear 60. For convenience in drawing, some or all the
gear teeth are not shown in various ones of the drawings, the
toothed meshing connection of the gears therein thus being only
schematically shown. See for example FIGS. 4, 10, 12, 13 and
14.
[0054] An output shaft 61 is fixed to and coaxially upstanding from
the output gear 60 (FIG. 12) and fixedly rotatably drives an
eccentric member 62 (FIGS. 5, 10 and 12) spaced above the output
gear 60. In this embodiment, the output shaft is of rectangular
cross-section to maximize its torque transmitting capability.
[0055] The eccentric member 62 comprises a radially extending disk
63 (FIG. 5) coaxial with the output shaft 61 and fixedly surmounted
by an eccentric circular cylinder 64 eccentrically rotatable with
the output shaft 61.
[0056] The link member 51 is generally T-shaped, as seen in FIG.
13, having a plate-like body 70 overlying the disk 63 of the
eccentric member 62 and lying at right angles to the output shaft
61, and further having a plate-like fork 71 fixed at the rightward
(FIGS. 5, 10, 12 and 13) end of the plate-like body 70 and
extending in a plane substantially parallel to the output shaft 61.
The plane of the plate-like fork 71 is perpendicular to the
intended direction of reciprocating movement of the link member 51.
The body 70, at its end portion remote from the fork 71, has an
oblong through opening 72 snugly radially receiving the rotating
eccentric cylinder 64 of the eccentric member 62, as seen in FIG.
10. More particularly, the length direction of the oblong opening
72 extends parallel to the plane of the fork 71 and is of
sufficient length to accommodate 360.degree. rotation of the
eccentric cylinder 64 without movement of the body 70 parallel to
the plane of the fork 71. On the other hand, the width of the
oblong opening 72, namely in a direction perpendicular to the plane
of the fork 71, corresponds substantially to the diameter of the
eccentric cylinder 64, providing a sliding clearance between the
body 70 and eccentric cylinder 64, so that rotation of the
eccentric cylinder 64 will result in reciprocation of the link
member 51 in a direction perpendicular to the plane of the fork
71.
[0057] The plate-like body 70 includes a thickened rim 73 (FIG. 5)
around the oblong opening 72 and may thus be said to form a yoke
for coaction with the eccentric cylinder 64. The side edges of the
body 70 are preferably also thickened to form parallel longitudinal
guide rails 74 (FIG. 10).
[0058] The above discussed moving elements of the transmission 50
are located and movably supported within the shell 26 as follows.
The face gear 54 has coaxial downward and upward (FIGS. 5-7, 10 and
12) extending stub shafts 75 and 76 respectively rotatably
supported in coaxial bearing bosses 80 and 81 respectively fixed on
the opposing faces of the shell parts 31 and 30 (FIGS. 6, 7 and
12). Similarly, the output gear 60 and the eccentric member 62 have
respective downward and upward extending stub shafts 82 and 83
coaxial with the output shaft 61 and rotatably supported in
respective cylindrical bearing bosses 84 and 85 in the respective
shells 31 and 30 (FIGS. 5-7 and 12). The link member 51 is slidably
guided for reciprocation in a notch 90 (FIGS. 5 and 7) in the
peripheral wall 91 of the left (upper in FIG. 5) shell part 30. The
notch 90 has parallel opposed guide faces 92 (FIG. 7) spaced apart
to snugly slidably guide therebetween the opposite guide rails 74
of the link member 51, and thus spaced at substantially at the
maximum width of the link member. The thickness of the link member
is guided for reciprocation between the peripheral edge 93 of the
right (lower in FIG. 5) shell 31 and the width wall 94 (FIGS. 5 and
7) of the other shell part 30.
[0059] The central length axis LA (FIG. 10) of the link member
intersects the central length axis MA of the motor shaft 52 at the
axis SA of the output shaft 61 and stub shaft 83 (FIGS. 10 and 12),
at an angle equal to the angle between the central length axis of
the handle 12 and barrel 13 of the housing 11. Moreover, the length
axes of the handle and barrel also intersect at the axis SA of the
output shaft 61 when the drive unit 25 is installed in the
handpiece housing 11 as hereafter discussed. In effect then, the
link member longitudinal axis LA and motor shaft axis MA define the
length axis of the barrel 13 and handle 12, respectively, when the
drive unit 25 is installed in the handpiece housing 11.
[0060] The drive unit 25 is located within the handle 12, as
follows. As seen in FIGS. 3 and 4, transverse ribs 95 are molded
into the interior surface of the handle 12 at opposing locations in
the left and right housing parts 14 and 15 (FIGS. 2-4). For drawing
convenience, only the ribs in the right housing part 15 are shown,
the ribs in the left housing part 14 being compatible. The ribs 95
locate the drive unit 25 in the rightward/leftward direction in
FIG. 2. Further, the drive unit shell bosses 84 and 85 (FIG. 5)
protrude sideways from the drive unit shell and are pivotally
received in corresponding hollow cylindrical bosses, one of which
is shown at 96 in FIG. 2, and which extend toward each other from
the interior of the left and right housing parts 14 and 15. The
hollow cylindrical boss 96 of the left housing part 14 is not shown
but is opposed to and compatible with the housing part 96 shown in
the right housing part 15 of FIG. 2. The drive unit 25 is thus,
except for the lateral positioning defined by the ribs 95,
pivotally located within the handpiece housing 11 and is thus
capable of some pivotal floating in the housing to achieve proper
alignment of the longitudinal movement axis LA (FIG. 7) of the link
member 51 with respect to the barrel 13 and a pump unit 100 (FIGS.
2-4 and 16-18) located in the barrel 13 as hereafter discussed.
Pump Unit
[0061] Turning now to the pump unit 100, attention is directed to
FIGS. 2-4 and 16-18. The pump unit 100 includes a bellows 101
including an axially expandable and contractible, reciprocating,
flexible bellows wall 114 (FIG. 18) and a forwardly extending,
rigid, annular flange wall 102. Such flange wall 102 is loosely
telescoped over a rigid rearwardly extending annular flange 103 of
a rigid, forwardly extending coaxial bellows housing 104.
[0062] The bellows 101 and bellows housing 104 are preferably of
molded plastics material. A resilient O-ring 105 (FIGS. 16 and 19)
is snugly radially disposed between the radially opposed, axially
extending annular flanges 102 and 103, to create a fluid seal
therebetween and hence between the bellows 101 and bellows housing
104, to prevent fluid leakage therebetween. The bellows 101 and
bellows housing 104 have respective axially spaced radially
extending steps 106 and 107 joined to the respective annular
flanges 102 and 103 and axially spaced apart at a distance
substantially greater than the diameter of the O-ring 105, as seen
in FIG. 19. The axial extending flanges 102 and 103 and radially
extending steps 105 and 106 define an annular chamber 110 in which
the O-ring 105 is axially loosely, and radially snugly and
sealingly, disposed. Note that the radially opposed surfaces of the
axially extending annular flanges 102 and 103 are cylindrical, such
that neither has an annular groove in which the O-ring seats. Thus,
the O-ring is free to roll on the radially opposed cylindrical
surfaces of the axially extending flanges 102 and 103 and the
O-ring 105 does not significantly interfere with axial separation
of the bellows 101 and bellows housing 104 from each other.
[0063] Instead, such axial separation is prevented, as hereinafter
further discussed, by a forwardly-rearwardly
(leftwardly-rightwardly in FIG. 2) spaced pair of ribs 111 (FIG. 2)
extending radially inward from the interior wall of the right
housing part 15 and a corresponding, laterally opposed pair of
mirror imaged ribs (not shown) extending laterally inward from the
interior wall of the left housing part 14. Such ribs 111 are also
schematically indicated in FIG. 18.
[0064] The rear (right in FIG. 19) end of the bellows housing axial
flange 103 abuts the radially extending step 106 of the bellows 101
and the forward (leftward in FIG. 19) end of the bellows axial
flange 102 axially abuts a radial flange 112 which extends radially
outward from and forwardly from the bellows housing step 107. The
forward end of the bellows axial flange 102 thus radially overlaps
the bellows housing step 107 in snug but axially slidable relation
thereto. A small forwardly extending annular rib 113 protrudes
forwardly from the bellows radial step 106 toward the O-ring 105 to
prevent rearward escape of the O-ring 105 from the space between
the axially extending flanges 102 and 103, in the event of slight
axial shifting of the bellows 101 and bellows housing 104 away from
each other.
[0065] The above mentioned radially inward extending ribs 111 of
the handpiece housing 11 snugly axially oppose and sandwich
therebetween the bellows radial step 106 and bellows housing radial
flange 112 to positively prevent axial separation of the bellows
101 from the bellows housing 104, when the pump unit 100 is
installed in the housing 11.
[0066] The above-mentioned bellows wall 114 extends rearward from
the inner periphery of the radially extending annular step 106 of
the bellows 101 (FIG. 18) and consists of an axially collapsible
and extensible, flexible, wave cross-section, peripheral wall 114.
The bellows wall 114 surrounds an axially expansible and
contractible pumping chamber 115. At the rear end of the bellows
101, a radially extending drive end wall 116 closes the rear end of
the bellows wall 114 and pumping chamber 115. A stub 120, having a
radially enlarged head 121, is fixed to and extends coaxially
rearwardly from the drive end wall 116.
[0067] To axially reciprocatingly drive (repetitively axially
contract and expand) the bellows 101, the above discussed link
member 51 (FIG. 5) of the drive unit 25 has its fork 71 provided
with a central, radially opening, generally U-shaped slot 122
(FIGS. 11-13). The slot 122 divides the fork 71 into a pair of
tines 123 (FIG. 11). The slot 122 opens leftwardly in FIG. 2,
namely away from the rightward housing part 15 and toward the
leftward housing part 14. Thus, with the drive unit 25 located in
the right housing part 12 as seen in FIG. 3, the pump unit 100 can
be inserted into the rightward housing part 15, with the stub 120
(FIG. 18) inserted in the slot 122 of the fork 71 (FIG. 11) so as
to trap the tines 123 axially between the drive end wall 116 and
head 121 of the bellows 101, as generally indicated in FIGS. 3 and
4. To prevent the bellows stub 120 from accidentally radially
escaping out the open end of the slot 122 in the fork 71, the
central portion 124 (FIG. 11) of the slot 122 is undercut by inward
tapering of an intermediate portion 125 of the slot 122 as seen in
FIG. 11. The tapered portion 125 of the slot 122 (FIG. 11) defines
a snap fit detente for resiliently trapping the bellows stub 120 in
the drive unit slot 122. Thus, to install the bellows stub 120 in
the slot 122, the bellows stub 120 must be resiliently forced
through the tapered portion 125 of the slot 122 and upon passing
the latter, the stub resiliently snaps into the central portion 124
of the slot. The inner ends of the tapered portion 125 of the slot
resiliently maintain the stub radially inboard thereof, in the
central portion 124 of the slot 122.
[0068] The stub 120 and hence the bellows 101, and indeed the
entire pump unit 100, is thus freely rotatable about its length
axis with respect to the fork 71, so that the circumferential
orientation of the drive unit 25 and the pump unit 100 is
determined by the location thereof in the housing. The drive unit
25 and pump unit 100 are thus, to an extent, free to
circumferentially float with respect to each other, about the
connection of the stub 120 and fork 71, without interfering with
the circumferential location of the drive unit 25 and pump unit 100
in the housing 11. Further, the edges of the slot 122, in
particular of the central portion 124 thereof, are rounded in
cross-section, as is the stub 120, to permit a modest amount of
angular adjustment between the length axes MA and LA of the drive
unit 25 and pump unit 100 and to allow the drive unit 25 and pump
unit 100 to easily settle into their proper operating positions in
the housing 11.
[0069] A cylindrical plug 126 is coaxially fixed to the interior
side (left side in FIG. 18) of the bellows drive end wall 116 by a
coaxial, rearward extending, undercut pin 127 snap fitted in a
forwardly (leftwardly in FIG. 18) opening recess in the stub 120.
The plug 126 has a diametral slot 130 opening forward from its
front end and which faces forward toward a resilient valve member
131 (FIGS. 16 and 18) to maintain liquid communication between the
central and radially outer portions of the pumping chamber 115.
[0070] The bellows 101 is thus a single element which carries out
four different functions, namely sealing at the forward end,
changing the pump chamber size in the middle thereof, the rear end
acts as a piston and as a drive point. In addition, the front
annular flange 102 helps locate the pump unit with respect to the
housing barrel.
[0071] The pump unit 100 further includes a valve member 131, which
is a one piece member of suitable resilient material and which by
itself constitutes the entire moveable inlet and outlet valve
system for the pump unit 100. More particularly, the valve member
131 comprises a short tubular central portion 132 (FIG. 18) which
coaxially connects a forward (leftward in FIG. 18) tapering, duck
bill type, outlet valve 133 and a rearwardly and radially outwardly
extending umbrella type, inlet valve 134. The umbrella valve 134 is
annular and has a central opening 135 which communicates coaxially
from the pumping chamber 115 in the bellows 101 forwardly through
the tubular central portion 132 and outlet duck bill valve 133 of
the valve member 131.
[0072] The bellows housing 104 comprises a rear (right in FIGS. 18
and 18C) facing recess having a perimeter defined by the annular
flange 103 of the bellows housing 104 and a rear facing radial wall
136 which defines the front end of the pumping chamber 115. The
umbrella valve 134 lies coaxially in the resulting recess 103, 136.
The forward facing perimeter 137 of the umbrella valve 134, in its
closed condition shown in FIGS. 18 and 18C, presses forward against
the radial wall 136 to seal thereagainst. The valve member 131 is
held against the right (rearward) movement away from the bellows
housing wall 136 by axial interference between a rightward facing,
radially outward extending, annular step 140 (FIG. 18C) at the rear
(right) end of the duck bill valve 133, and a radially inward
extending, leftward facing, annular flange 141 of the bellows
housing 104. The radially inward directed, annular flange 141 is
axially interposed between, and forms a port 142 between, the rear
facing recess 103, 136 and a coaxial, forwardly extending,
cylindrical, irrigation liquid outlet, discharge, conduit 143
(FIGS. 18 and 18C). The tubular central portion 132 of the valve
member 131 extends snugly axially through the port 142.
[0073] To install the valve member 131 in the bellows housing 104,
the tapered outlet duck bill valve 133 is pushed forward through
the port 142, the bellows valve step 140 snaps forwardly
(leftwardly in FIG. 18C) past the bellows housing flange 141, and
the sealing perimeter 137 of the umbrella valve 134 is thereby
pulled forwardly resiliently against the rearward facing bellows
housing wall 136, leaving the valve member 131 with its duck bill
valve 133 and umbrella valve 134 both in their closed condition
shown in FIGS. 18 and 18C.
[0074] The bellows housing 104 further includes an annular liquid
jacket 144 (FIGS. 18 and 18C) surrounding the rear portion of the
liquid outlet conduit 143 and defining radially therebetween an
annular liquid inlet chamber 145 (FIGS. 18, 18C and 19). The inlet
chamber 145 communicates between a radial inlet port 146 (FIGS. 16
and 19), which opens radially outward through the side of the
bellows housing 104, and an annular space 147 (FIG. 18C). The
annular space 147 is bounded by the forward face 150 and tubular
central portion 132 and sealing perimeter 137 of the umbrella valve
134 and the radial face 136 of the recess 103, 136 of the bellows
housing 104.
[0075] Thus, a rightward pullback of the bellows head 121 axially
expands the bellows, from its FIG. 18A position towards its FIG. 18
position. This reduces the pressure within the bellows. This in
turn keeps the duck bill valve 133 closed and pulls the sealing
perimeter 137 of the umbrella valve 134 rightwardly away from the
bellows housing recess radial wall 136 and draws liquid from the
port 146 through the annular inlet chamber 145, around the
perimeter 137 of the open umbrella valve and into the interior of
bellows.
[0076] On the other hand, a leftward push forward of the bellows
head 121 axially compresses the bellows from its FIG. 18 position
toward its FIG. 18B position and raises the pressure in the
bellows, to close the umbrella valve 134 and open the duck bill
valve 133 and force a pulse of liquid out of the bellows forwardly
through the duck bill valve 133 and liquid outlet conduit 143.
[0077] Irrigation liquid is drawn to the inlet port 146 of the
bellows housing 104 through an elbow 151 (FIG. 19). The outlet end
152 of the elbow and the inlet port 146 are cylindrical, with the
elbow outlet end 152 being a snug axially sliding fit in the inlet
port 146. An axially elongate, annular groove 153 in the outer
periphery of the elbow outlet 152 houses a seal ring, here an
O-ring, 154 which bears sealing and rollingly on the radially
opposed and surrounding surface of the inlet port 146 to prevent
liquid leakage out of the elbow 151 at its interface with the inlet
port 146. The elbow 151 is not mechanically interlocked with the
inlet port 146 but can slide in and out with respect thereto. The
elbow 151 is held in place with its outlet end 152 sealingly within
the port 146 by bearing of a portion 155 (FIG. 4) of the handpiece
housing barrel 13 against the outboard surface 156 of the elbow
151, with the pump unit installed in the handpiece housing 11. The
elbow 151 here fixedly carries a pair of parallel fins 157 (FIGS.
16, 17 and 19). The fins 157 extend radially from the rear inlet
end portion of the elbow 151 and axially sandwich therebetween the
flanges 106 and 112 of the bellows 101 and bellows housing 104, at
least to help the housing ribs 111 (FIG. 18) fins 157 prevent axial
separation of the bellows and bellows housing. The housing ribs 111
and fins 157 are more or less evenly circumferentially located
around the bellows 101 and bellows housing 104.
[0078] An elongate flexible irrigation liquid supply hose 160
(FIGS. 2, 4, 16, 17, 19, 22, 23, 25 and 29) has a forward end 161
which telescopes sealing and fixedly over the rear end 162 of the
elbow 151 as seen in FIGS. 19 and 29. Although an annular barb is
shown at 162 (for example in FIG. 19) a barbless, cylindrical end
162 is satisfactory. In the assembled handpiece, the irrigation
liquid hose 160 extends rearward from the elbow 151 (FIG. 4) in the
barrel 13 of the housing and angles downwardly and rearwardly along
the bottom of the handpiece handle 12 to exit rearwardly and
downwardly through a hole 163 (FIG. 2) in the bottom end wall 164
of the handpiece housing 11. A clamp plate 165 (FIGS. 2, 3 and 4)
of bent cross-section has a perimeter groove 166 for receiving the
edges of the hole 163 in the housing bottom end wall 164, such that
the clamp plate 165 is trapped in and partly closes the hole 163 in
the bottom end 164 of the housing handle 12 when the housing is
fully assembled. A notch 167 (FIG. 2) in the rightward end of the
clamp plate 165 permits exit therethrough of irrigation liquid
supply hose 160 from the handpiece housing 11 and snugly and
frictionally grips such hose, without crushing or collapsing it, so
that such hose 160 cannot easily be pulled out of the housing 11 or
off the elbow 151.
[0079] The irrigation liquid hose 160, the inlet line, has fixed on
the outside thereof, as by extruding or molding integrally
therewith, a smaller diameter rib 170 (FIGS. 2, 16 and 17). A
plurality (here three) of insulated electrical conductors (wires)
171 have intermediate portions contained within and extending the
length of the rib 170. Forward end portions of the insulated wires
171 emerge from the forward end of the rib 170 and carry
conventional electrically conductive connectors 175. The forward
end of the rib 170 extends through the notch 167 (FIG. 2) and ends
just inside the bottom portion of the handle 12/Thus, as apparent
from the below description, rib 170 functions a cable through which
conductors 171 extend from the battery pack to the handpiece
housing 11.
[0080] The insulated electrical conductors 171 extend along the
length of the central portion of the liquid supply hose 160 and
have rear ends provided with respective electrically conductive
connectors 176 (FIGS. 22 and 29), such that electric current can
flow from a given rear connector 176 through its corresponding
insulated electrical conductor 171 and to its corresponding front
electrically conductive connector 175 in a conventional manner.
Short rear portions of the conductors 171 are loose and moveable
with respect to the liquid supply hose 160 as seen in FIGS. 22 and
29.
[0081] The electrical connectors 175 and 176 are conventional crimp
type connectors.
[0082] Instead of being molded in or otherwise constrained within
the generally circular cross section rib 170 in FIG. 2, the
elongate central portion of the insulated electrical conductors 171
may be fixed side by side, in a flat array, to the outside of the
liquid hose 160, as shown in FIGS. 22 and 29, and such can be
accomplished by adhesive bonding or by any other convenient
means.
[0083] The hose 160, 170 thus serves the dual use of conveying both
irrigation liquid and electric operating power.
[0084] The length of the central portion of the liquid hose 160, to
which the insulated conductors 170 are fixed, preferably extends
several feet (for example 8 to 10 feet) from the handpiece 10. The
rear end 177 (FIGS. 22 and 23) of the liquid hose is here provided
with a fitting 180 of hollow tubular construction open to axial
liquid flow therethrough. The fitting 180 comprises a forward end
portion 181 (FIG. 23) fixed sealingly telescoped in the rear end
177 of the liquid hose 160, a square central flange 182 (FIG. 22)
and a rear end portion (or "spike") 183 having a sharpened tip 184.
The tip 184 is capable of conventional insertion into a
conventional source S (FIG. 22) of irrigation liquid, for example a
conventional supply bag, for conveying irrigation liquid therefrom
forward into the hose 160. The square flange 182 prevents rotation
of the fitting 180 in the casing 191, which helps when removing the
spike 183 from the liquid supply bag. In the embodiment shown, the
rear end portion 183 is covered by a protective cap 185 prior to
use so that the sharpened tip 184 will not accidentally be
dulled.
[0085] Thus, the length of the liquid supply hose 160 allows the
irrigation liquid source S to be located at a distance from the
handpiece and thus out of the way of the surgical personnel at the
operating table where the handpiece 10 is to be used.
Electrical Power Supply Unit
[0086] To provide operating electrical power to the motor 36, a
compact, self contained electrical power supply unit 190 (FIGS.
20-25) is fixed on the rear end portion 177 of the liquid hose 160.
The power supply unit is thus located remotely from the handpiece
10, adjacent to the source S of irrigation liquid.
[0087] The power supply unit 190 comprises a casing 191 preferably
of rigid molded plastics material. The casing 191 here comprises a
relatively deep, substantially rectangular pan 192 (FIG. 2) whose
top (as oriented in FIGS. 22 and 23) is fixedly closed by a cover
193. The pan 192 has front and rear end walls 194 and 195 (FIGS.
23, 23A and 24) having fixed upward opening slots 200 each defined
by a laterally spaced, opposed pair of U-shaped flanges 201 (FIGS.
23A and 23B). The slots 200 are undercut in that each has a mouth
202 laterally narrower than the remainder of the slot 200 and
communicating between the remainder of the slot 200 and the
interior cavity of the pan 192. The undercut slots 200 are of
constant cross-sectional size and shape vertically (i.e. into and
out of the page in FIG. 24 and up and down in FIG. 23).
[0088] For convenient reference in the drawings, the reference
numerals 200 and 201 are suffixed, so that the undercut slots and
U-shaped flanges on the front pan wall 194 are indicated by the
reference characters 200F and 201F and the undercut slots and
U-shaped flanges on the rear pan wall 195 are indicated at 200R and
201R.
[0089] The U-shaped flanges 201F defining the slots 200F on the
forward end wall 194 start substantially from the pan bottom wall
196 and extend a bit less than half way up the front end wall
194.
[0090] On the other hand, the U-shaped flanges 201R of the slots
200R on the rearward end wall 195 of the pan are spaced above the
bottom wall 196 of the pan upon respective block-like pillars 203
which define an up-facing bottom 204 for each of the U-shaped
flanges 201R on the rear pan wall 195.
[0091] Rising from bottom wall 196 of the pan between the two
central pillars 203 to a height below the bottoms 204 of the slots
200R thereof, is a central block 205 from which forwardly extends,
along the pan bottom wall 196, a T-shaped flange 206 (FIG. 23B) of
constant cross section vertically and defining a pair of vertically
open and laterally oppositely opening grooves 207 disposed
immediately forward from the two central pillars 203 on the rear
pan wall 195.
[0092] Two such undercut slots 200F are spaced symmetrically side
by side on the front pan wall 194. Similarly, and at the same
effective lateral spacing, two such slots 200R are spaced laterally
side by side on the pan rear wall 195.
[0093] Springy, electrically conductive sheet metal battery
contacts of three different kinds are indicated at 210 and 211 and
212 and FIGS. 26, 27 and 28 respectively.
[0094] A pair of such contacts 210 are provided and each comprises
a generally rectangular foot 213 adapted to snugly slide down into
a respective undercut slot 200F at the pan front wall 194. Each
foot 213 is provided with resilient toes 214 angled out of the
plane of the foot 213 and adapted to bite against the interior of
the corresponding undercut slot 200F to fix the corresponding
battery contact 210 in place therein.
[0095] Similarly, each of a pair of battery contacts 212 (FIG. 28)
has a resilient fork-shaped foot 215 adapted to fit snugly and
slidingly down into the corresponding undercut groove 200R at the
rear wall 195 of the pan 192 and with springy toes 216 for fixedly
gripping the interior of the corresponding undercut slot 200R.
[0096] In a generally similar manner the single, low speed battery
contact 211 (FIG. 27) has a resilient U-shaped foot 217 for sliding
down over the T-shaped flange 206 (FIG. 23B), with springy toes 218
bent out of the plane of the foot 217 for bitingly engaging the
walls of the grooves 207 of the T-shaped flange 206.
[0097] Each of the battery contacts 210, 211 and 212 thus slides
with its corresponding foot into the desired location with respect
to the grooves 200F, 200R and 207 and locks fixedly therein. This
is generally indicated in FIGS. 22-24. The battery contacts 210,
211 and 212 have respective resilient fingers 221, 222 and 223
(FIGS. 26, 27 and 28 respectively), two each for the battery
contacts 210 and 211 and one each for the battery contacts 212.
Such fingers 221, 222 and 223 protrude from the respective slots
200F, 200R and 207 into the interior of the pan 192 for
electrically contacting batteries 230 (FIG. 22) to be housed in the
pan 192. Further, the battery contact 211 and each of the battery
contacts 212 (FIGS. 27 and 28 respectively) have an upstanding
terminal (224 and 225 respectively) of simple rectangular shape for
releasable telescoped engagement within a respective one of the
connectors 176 at the rear ends of the three insulated electrical
conductors 171 (FIG. 22).
[0098] Turning now to the arrangement of the batteries 230 within
the pan 192, one embodiment according to the invention
advantageously uses batteries of a kind widely available in retail
stores, namely AA size alkaline batteries. In addition to their
wide availability to the public, these batteries advantageously are
inexpensive, have a long shelf life and provide full operating
voltage until almost fully discharged. In the embodiment shown,
eight such batteries 230 are provided and are individually
indicated at B1, B2, B3, B4, B5, B6, B7 and B8. As shown in FIGS.
22-24, ribs 231 extending circumferentially within the pan 192
cradle the batteries 230 fixedly but removably within the pan 192.
The polarity of the eight batteries is indicated by "plus" signs
marked thereon. As seen in the drawings, the batteries 230 are
arranged in four rows of two head-to-tail batteries each. Four of
the batteries 230 lie in the bottom (FIGS. 22 and 23) of the pan in
two rows of two each and the remaining four batteries 230 lie on
top of those.
[0099] The ends of the battery rows bear variously on the above
discussed battery contacts 210, 211 and 212 as generally indicated
for example in FIG. 22 and also in the schematic circuit drawing in
FIG. 22A. More particularly, the four batteries B1, B2, B3 and B4
defining a vertical plane nearest to the viewer in FIG. 23 are
connected in series from the near connector 212 leftwardly through
the top row of batteries, down through the near upstanding
connector 210 and thence rightwardly through the bottom pair of
batteries to the lower rear connector 211. The remaining four
batteries B5-B8 are arranged in a vertical plane behind
above-mentioned batteries B1-B4. More particularly, the batteries
B5-B8 connect in series from the far side of the lower rear
connector 211 forwardly (leftwardly in FIG. 22) to the far
connector 210, upwardly therethrough, and then rearwardly back to
the far upper connector 212.
[0100] The cover 193 (FIGS. 23 and 25) has plural, laterally
extending, depending ribs 232 (FIGS. 23 and 25) intended to seat
upon the uppermost batteries B1, B2, B7 and B8 and fix the
batteries B1-B8 in the pan with the cover 193 fixed in its normal
closed position atop the pan 192. The cover is fixedly securable
atop the pan by any convenient means, such as snap fit connectors,
a portion of which are generally shown in 233 in FIG. 22, and
generally like those discussed above with respect to the handpiece
housing 11, as at 16, and as generally discussed with respect to
the drive unit shell 26, as at 32, 33.
[0101] The aforementioned rear end 177 of the hose 160 extends
through the casing 191 along the horizontal parting plane between
the pan 192 and cover 193, and so lies close adjacent the topmost
batteries B1, B2, B7 and B8.
[0102] Hollow front and rear bosses 234 and 235 (FIGS. 23 and 25)
extend forward and rearward respectively, from the casing 191. At
the parting plane between the pan 192 and cover 193, the bosses 234
and 235 are notched (for example at 236 in FIG. 22) for extension
therethrough of the rear end 177 of the liquid hose 160. The rear
hollow boss 235 is sized and shaped to receive radially therein the
square flange 182 (FIG. 23) on the rear end of the liquid hose 160,
and thereby axially fix the rear end of the liquid supply hose 160
within the casing 191 and nonrotatably fix the fitting 180 to the
battery casing 191. The notch 236 in the front boss portion 234 on
the cover 193 is indented by one or more small recesses 237 for
receiving axially therethrough the rib 170 containing the insulated
electrical conductors 171, whose rear end connectors 176 are
respectively fixed to the terminals 224 and 225 of the battery
contacts 211 and 212.
Trigger Unit
[0103] The handpiece 10 further includes a trigger unit 240 (FIGS.
2-4) for controlling actuation of the motor 36 and, by extension,
pump unit 100. The trigger unit 240 comprises a generally L-shaped
trigger member 241 (FIGS. 2, 4 and 4A) that functions as a control
switch and that comprises an elongate trigger lever 242. The upper,
forward (leftward in FIGS. 2 and 4) end of the trigger lever is
pivoted by laterally extending integral pins 243 pivotally
receivable in suitable holes in laterally opposed bosses 244 (one
of which is shown in FIG. 2) in the opposing lower edges of the
housing parts 14 and 15, near the rear end of the barrel 13.
Snapping together of the two housing parts 14 and 15 thus captures
the pivot pins 243 and pivotally mounts the trigger with respect to
the handpiece housing 11.
[0104] The trigger lever 242 includes a transverse ridge 245 (FIG.
4) near to but spaced rearwardly from the pivot pins 243 and facing
the underside of the barrel 13 and adapted to bear on the underside
thereof in the manner of a fulcrum. By far the major length 246 of
the trigger lever 242 is to the rear (right in FIG. 4) of the
fulcrum ridge 245. This rearward trigger part 246 is relatively
rigid in the portion thereof spaced at least somewhat to the rear
of the fulcrum ridge 245. Such rigidity is assisted by a forward
facing longitudinal reinforcement rib 247 extending rearward along
the front face of the trigger lever 242 from a point near the
fulcrum ridge 245. The front of the trigger lever 242, to the rear
of the fulcrum ridge 245 is, in the embodiment shown, provided with
transversely extending ribs 248 to provide the user with a non-slip
grip of the trigger lever 242.
[0105] The trigger lever 242 is bendable near the fulcrum ridge
245, both to the front and rear thereof, in a resilient manner. In
this way, the resilience of the trigger lever tends to hold it in
its forward, inactive position shown in FIG. 4, with the fulcrum
ridge 245 bearing on the underside of the handpiece barrel 13. On
the other hand, when the user grips the handle 12 and squeezes the
trigger lever 245 toward it, in the direction indicated by the
arrow TA in FIG. 4, the trigger lever bends in the region of the
fulcrum ridge 245, tending to straighten from its relaxed convexly
forwardly curved configuration of FIG. 4, so that the rear face of
the trigger lever can be pulled into the dotted line position 242P,
substantially against the front face of the handle 12. Upon release
of the trigger by the user, the natural resilience of the trigger
lever 242 unbends it back to its solid line forward position shown
in FIG. 4. Accordingly, the trigger naturally returns forward to
its non-operative position without need for a separate return
spring.
[0106] The trigger arm 251 fixedly carries a thumb 250 (FIG. 4A)
intermediate it ends in the housing handle 15 and which interferes
with the housing wall adjacent the hole 252, to prevent the
resilient restoring force of the trigger lever 242 from pulling the
trigger arm 251 leftwardly (FIG. 4A) out of the housing handle
12.
[0107] A plank-like switch contact support arm 251 (FIGS. 2, 4 and
4A) protrudes substantially at a right angle from the rear, or
bottom, end of the trigger lever 242 and extends upwardly and
rearwardly (in FIG. 4) into the lower portion of the handle 12,
loosely through a hole 252 (FIG. 4A) in the opposing bottom wall of
the handle. A plate-like electrically conductive contact blade 253
fixedly extends through the thickness of the arm 251, and has a
front portion exposed towards said motor and a rear portion exposed
toward the bottom end 164 of the handpiece handle.
[0108] A pair of rectangular posts 255 and 256 protrude fixedly
into the interior of the handle 12 from the inside of the right
housing part 15, about midway between the drive unit 25 and the
housing bottom end 164 (FIGS. 4A and 4B). Each post 255 and 256
includes a T-shaped flange 260 extending substantially forward
toward the drive unit 25. Each T-shaped flange 260 defines a pair
of oppositely facing grooves 261 (FIG. 4C).
[0109] Electrically conductive, spring-like metal contacts 262 and
263 (FIGS. 4A and 4C) each have a substantially U-shaped foot 264
for reception on the T-shaped flange 260 of the corresponding posts
255 and 256. The contacts 262 and 263 further each have a
substantially rectangular, projecting terminal 265 for telescopic
fixing thereon, in electrically connected relation, a corresponding
one of the front connectors 175 of the three insulated electrical
conductors 171. The electrical contacts 262 and 263 further have
respective, generally L-shaped, plate-like, flexible contact leaves
266 and 267 (FIG. 4C). The contact leaves 266 and 267 extend toward
the drive unit 25 as seen in FIG. 4A.
[0110] Protruding rearwardly from the motor 36 are a pair of
electrically conductive contacts 270 and 271 (FIGS. 4A and 9). The
contact 271 is a conventional terminal (like those at 224, 225 and
265) for receiving one of the front connectors 175 in fixed and
electrically conductive relation thereon.
[0111] In contrast, the contact 270 is an elongate, springy
rectangular piece, bent intermediate its ends in dogleg fashion,
and angling from the rear end of the motor 36 rearwardly and
somewhat rightwardly (in FIG. 4A) to a free end portion spaced near
the contact leaves 266 and 267.
[0112] Gradual pressing of the trigger lever 242 toward the handle
housing (rightwardly in FIGS. 4 and 4A) moves the arm 251 and hence
the contact blade 253 progressively further into the handle 12
through a series of positions, three of which are indicated in
broken lines at 253A, 253B and 253C in FIG. 4A.
[0113] The free (rightward in FIG. 4A) end of the arm 251 is
beveled at 272 to help it ride over the contacts 266 and 267 as the
trigger lever 242 is sequentially squeezed more and more toward the
handle 12. The arm 251 is progressively resiliently bent, like a
leaf-spring, as its free end rides over the fixed contacts 266 and
267, to firmly press its contact blade 253 against the latter.
[0114] Thus, as the trigger lever 242 is pressed toward the handle
12, the beveled free end of the arm 251 rides over the contact leaf
266 past its dotted line position 253A and toward its dotted line
position 253B. As the free arm end approaches position 253B, the
contact blade 253 slides into electrical contact with the contact
leaf 266 and the motor contact 270 to establish electrical
connection therebetween. The motor contact 270 resiliently bends to
allow continued travel of the contact blade 253 and arm 251 further
into the handle, as indicated in dotted line at 270B, and to press
firmly against the contact blade 253. Given only a light pull on
the trigger lever 242, the arm 251 and contact blade 253 tend to
stop in the position indicated in dotted lines at 253B, by reason
of the free end of the arm 251 colliding with the contact leaf 267.
In this "B" position, electric current is fed to the motor 36 only
from half the battery collection, namely batteries B1, B2, B3 and
B4 in FIG. 22A. The motor 36 thus runs at only a preselected
fraction of its full speed and the pump unit 100 outputs irrigation
liquid pulses at a desired frequency and amplitude, which are less
than the maximum available. The apparatus is thus operated in its
low output mode. The colliding of the free end of the trigger arm
251 with the contact leaf 267 gives tactile feedback to the user,
that the low output mode of the handpiece has been selected.
[0115] Further pulling in of the trigger lever 242 by the user
causes the beveled free end of the arm 251 to bend rightwardly
(FIG. 4A) the contact leaf 267 to a dotted line position indicated
at 267C, allowing the free end of the arm 251 to override the
contact leaf 267, such that the contact blade 253 moves into its
"full-pull" dotted line position 253C and further bends the motor
contact 270 its dotted line position 270C. In this final position,
the contact blade 253 establishes electrical contact between the
motor contact 270 and the contact leaf 267, thereby applying the
full series voltage of all eight of the batteries B1-B8 to the
motor 36 to operate the latter at its full speed and thereby drive
the pump unit 100 at its full output, namely to provide irrigation
liquid pulses out of the pump unit 100 at maximum pulse amplitude
and frequency.
[0116] When the user releases the trigger lever 242, the
resiliently bent trigger lever 242, due to its inherent resilience,
springs back from its fully pulled-in position indicated in broken
lines at 242P, to its solid line rest position indicated at 242
(FIG. 4A). The electrical connection between the contact 262 or 263
and the contact 270 is broken.
Suction Hose
[0117] A flexible suction hose 280 (FIGS. 2 and 3) is led along
within the housing (within the lower part of the housing in FIG. 3)
past the drive unit 25 and pump unit 100. The above-mentioned clamp
plate 165 includes a tubular structure molded thereinto and defined
by a forward nipple 282 in the handle 12 and, in coaxial fluid
communicating relation therewith, a rearward nipple 283 which
extends rearwardly out of the bottom end 164 of the handpiece
handle 12. The rear end portion 281 of the suction hose 280 is
sealingly and fixedly telescoped over the front nipple 282. A
conventional flexible hose, not shown, is conventionally and
sealing telescopable over the rear nipple 283 for connecting same
to a conventional suction source, as schematically indicated at SS
in FIG. 3.
[0118] The front end portion 284 of the suction nose 280 is
sealingly telescoped over a rearward opening nipple 285 on a short
suction conduit 286 (FIGS. 2, 3, 16, 17 and 18). The suction
conduit 286 (FIG. 18) is fixed side by side, in piggyback fashion,
on the periphery of the irrigation liquid conduit 143 and hence is
a part of (preferably an integral plastic molded part of) the
bellows housing 104.
[0119] The clamp plate 165 serves several purposes. It provides a
suction hose connection, bears on the irrigation liquid hose where
it enters the handpiece housing, and helps align the rear
(rightward in FIG. 4) end wall portions of the housing halves as
they are assembled together, and in so doing, is itself fixed on
the housing. In addition, the clamp plate 165 is of one piece,
preferably a plastic molding, and is partially recessed into the
handpiece so that it does not make the handpiece look any
bigger.
Tip Unit
[0120] A tip unit 291 (FIGS. 8, 8A and 8B) is releasably fixable on
the front end of the handpiece 10 and extends forward therefrom for
applying irrigation liquid pulses and/or suction to a surgical site
indicated schematically at SU in FIGS. 8 and 8B. The tip unit 291
(FIG. 8) comprises a coupling 292, a front cover 293 fixed to the
front of the coupling 292, and an elongate hollow wand 294
extending forwardly from the coupling and front cover for aiming at
a surgical site SU. The coupling 292, cover 293 and wand 294 are
preferably one piece molded plastic units. The wand 294 is
preferably of clear plastics material.
[0121] The tip unit 291, and more specifically the coupling 292, is
releasably fitted in fluid tight relation to the front of the
bellows housing 104 of the pump unit 100 and is releasably latched
within the open front end of the handpiece housing barrel 13 as
hereinafter discussed.
[0122] More particularly, the coupling 292 (FIG. 8) comprises a
shallow, forward opening cup 295 having a flat base wall 296 from
which forwardly extends a shallow peripheral wall 297, thereby
defining a forward opening recess 300. Coaxial irrigation liquid
nipples 301 and 302 extend fixing rearwardly and forwardly,
respectively, from the base wall 296 and together define a coaxial
bore 303 therethrough and through the base wall 296. The rear
nipple 301 is snugly but slidably receivable rearwardly into the
open front portion of the liquid outlet conduit 143 of the bellows
housing 104. An O-ring 304 seats in an annular groove outward
facing on the rear nipple 301 and sealingly engages the interior of
the liquid outlet conduit 143 to prevent irrigation liquid leakage
therebetween.
[0123] The wand 294 includes a coaxial, relatively small diameter,
irrigation liquid outlet tube 305 which at its rear end is
telescoped fixedly and sealingly within the bore 303 of the front
and rear nipples 301 and 302 for receiving a pulsed flow of
irrigation liquid from the irrigation liquid outlet conduit 143 of
the bellows housing 104.
[0124] The coupling 292 further includes a suction nipple 306
fixedly extending rearward from the base wall 296 in spaced
parallel relation with the irrigation liquid nipple 301. The
suction nipple 306 is snugly insertable rearwardly coaxially into
the front opening suction conduit 286 of the bellows housing 104.
An O-ring 310 is axially sandwiched between the rear end of the
suction nipple 306 and a front facing annular step 311 at the rear
end of the suction conduit 286 to prevent leakage therebetween.
[0125] The coupling 292 further includes a leaf spring-like,
generally U-shaped latch arm 312 which extends rearward from the
peripheral portion of the base wall 296, curves radially outwardly
and forwardly, and extends forward past the front cover 293, in
radially outwardly spaced relation from the wand 294. A
wedge-shaped, transverse ridge 313 on the exterior base of the
latch arm 312 is approximately centered between the front and rear
ends of the latch arm. A circumferentially extending, radially
inward protruding rib 314 (FIGS. 2, 3 and 8) on the interior face
and at the open front end of the right housing part 15 (at the
front end of the barrel 13) opposes the latch arm 312, immediately
ahead of the ridge 313, with the tip unit 291 installed on the
front end of the handpiece 10 as shown in FIG. 8. The ridge 313 has
a front facing step which abuts interferingly with the housing rib
314 to releasably block removal of the tip unit from its installed
condition shown in FIG. 8. To remove the tip unit from the front
end of the handpiece, the user simply presses radially inward
against the forward protruding end portion 315 of the springy latch
arm 312, sufficient to radially inward displace the ridge 313 out
of interfering relation with the rib 314 and thereby unlatch the
tip unit from the front end of the handpiece. This allows forward
removing the tip unit 291 from the open front end of the handpiece
barrel 13 and removing of the irrigation liquid and suction nipples
301 and 306 from the liquid outlet conduit 143 and suction conduit
286 of the bellows housing 104.
[0126] The tip unit 291, or any alternative tip unit having a
substantially identical coupling and front cover, can be installed
operatively on the front end of the handpiece 10 by inserting same
into the open front end of the handpiece barrel 13 so that the
nipples 301 and 306 enter the liquid and suction conduits 143 and
286 respectively, to their position shown in FIG. 8. During this
installation, the forward facing slope of the wedge cross-section
transverse ridge 313 slides rearwardly past the housing rib 314,
bending the springy latch arm 312 radially inward as generally
indicated by the arrow L in FIG. 8, so that the wedge cross-section
ridge 313 can snap rearwardly past the rib 314 at the open front
end of the housing barrel 13. Thus, the tip unit 314 can be slid
axially into the front end of the barrel 13 and upon reaching its
innermost position latches itself against unintended removal. In
its installed condition of FIG. 8, the tip unit is substantially
rigidly fixed with respect to the front end of the bellows housing
104 and hence with respect to the handpiece barrel 13.
[0127] The front cover 293 (FIG. 8) comprises a plate 320 which
extends radially of the wand 294 and of the length axes of the
barrel 13 and the pump unit 100. The peripheral shape of the plate
320 conforms to the cross-sectional shape of the front end of the
barrel 13, so that the perimeter of the plate 320 is substantially
flush with the outer periphery of the open front end of the barrel
13, and so that the plate 320 effectively covers the open front end
of the barrel 13. The peripheral shape of the plate 320 and
cross-sectional shape of the front end of the barrel 13 in one
embodiment is generally D-shaped, with a generally flat underside
and a convexly curved top and sides. The plate 320 is not intended
to seal the open front end of the barrel 13 and so need not tightly
abut same. Since the peripheral wall 297 of the cup 295 fits easily
within the open front end of the barrel 13, the plate 320 extends
radially outwardly beyond the cup 295, as seen in FIGS. 8, 8A and
8B.
[0128] The front cover 293 includes an annular flange 322 extending
axially rearwardly therefrom, radially snugly into the cup 295 of
the coupling 292 to bottom rearwardly and sealingly against a
resilient gasket 321 which is disposed against the front face of
the base wall 296 of the cup 295. Respective holes in the gasket
321 loosely surround the front nipple 302 and leave fully open the
communication between the interior of the suction nipple 306 and
the interior of the cup 295. The front cover 293 further includes a
further annular flange 323 extending fixedly and forwardly from the
plate 320 in coaxial alignment with the through hole 324 in the
plate 320.
[0129] The rearward annular flange 322 of the front cover 293 is
fixedly secured within the cup 295 of the coupling 292 by any
convenient means, for example by snap fit connectors on the
opposing faces of such flange 322 and the peripheral wall 297 of
the cup 295. For example, the cup peripheral wall 297 may be
provided with several circumferentially spaced rectangular holes
325 (FIGS. 8A and 8B) for snap fit reception therein of small
radially outward extending protrusions schematically indicated at
326 on the outside of the rearward annular flange 322.
[0130] The wand 294 further includes a relatively large diameter
elongate suction tube 330 (FIGS. 8A and 8B) which loosely coaxially
surrounds the irrigation liquid outlet tube 305 (FIG. 8) and
extends substantially to the front end of the latter. The rear end
portion 331 of the suction tube 330 is radially enlarged to provide
a radially shallow, axially elongate flange protruding radially
outward therefrom and which is axially trapped between the plate
320 and the gasket 321 backed by the base wall 296. This serves to
rigidly fix the suction tube 330 with respect to the coupling 292
and front cover 293. A port 332 in the sidewall of the suction tube
330 near its rear end communicates with a loosely surrounding
annular chamber 333 defined between the plate 320 and base wall 296
of the front cover 293 and coupling 292 respectively.
[0131] The front end of the irrigation liquid tube 305 is held
coaxially fixed within the front end portion of the surrounding
suction tube 330 by any convenient means, such as radial,
circumferentially spaced, webs 334 (FIG. 8). Accordingly, with a
tip unit 291, of the general type above described, installed on the
front end of the handpiece, as shown in FIG. 8, irrigation liquid
pulses from the pump 100 pass forwardly within the liquid tube 305
and are projected from the front (left in FIG. 8) end thereof, as
schematically indicated by the arrows PL. At the same time, liquid
and particulate debris at the surgical site SU are drawn into the
front (left in FIG. 8) end of the suction tube 330, pass rearwardly
along the length thereof, through the port 332 into the chamber 333
and rearwardly through the nipple 306 and suction nipple 285.
[0132] With the exception of a few components such as the motor 44,
the various electrically conductive contacts, the elongate
insulated conductors, the various seal rings (for example 105, 154,
304 and 310, the gasket 321, as well as the suction and irrigation
liquid hoses, the remaining major components, while possibly
manufacturable of a variety of materials, are economically
manufacturable of available molded plastics materials. For example,
the valve member 131 may be of rubber or a synthetic substitute or
similar resilient plastic. Similarly, the bellows 101 is preferably
molded of a suitable resilient plastic material capable of the
bellows expansion and contraction movements shown in the drawings.
The trigger unit 240 and the latch arm 312, while of substantially
rigid plastics material, are elastically bendable to the extent
required to suit the present description. Similarly, components to
be snap-fitted together are substantially rigid but have sufficient
resilience to permit the required described snap fitting.
[0133] The present invention can be constructed at relatively low
cost and is thus practically manufacturable as a disposable tool,
both the handpiece 10 itself and the accompanying electric power
supply unit 190 being disposable after use with a single surgery
patient.
Operation
[0134] The apparatus is quickly and easily assembled. The drive
unit 25 (FIG. 12) is assembled by, in effect, "dropping in"
elements in proper sequence into the right (lower in FIG. 12) shell
31 and covering same with the other shell 30. More particularly,
output gear 60, face gear 54 and motor 36 (with attached pinion
gear 53 and electric contacts 270 and 271) are "dropped" into their
respective locations in the upturned shell part 31, in that
sequence. The rectangular shaft 61, topped by the eccentric member
62, drops into the corresponding hole in the output gear 60 and the
link member 51 drops onto the eccentric member. The other shell
part 30 is then snap fitted over the filled shell part 31,
completing the drive unit 25.
[0135] The pump unit 100 is assembled by coaxially telescoping
together its elements shown in FIG. 18 and then plugging into the
inlet port 146 (FIG. 19) the elbow 151 with the O-ring 154 and hose
160 assembled thereon.
[0136] The stub 120 (FIG. 18) of the drive unit 100 can then be
snapped into the slot 122 of the drive unit fork 71 (FIG. 2) to
connect the drive unit 25 operatively to the pump unit 100. The
suction hose 280 can then be connected to the pump unit nipple 285
and to the nipple 282 on the clamp plate 165. Thereafter, the two
assemblies above described can be laid into the rightward (FIG. 2)
housing part 15 in the following order, namely liquid hose 160
(FIG. 4), drive unit 25 and pump unit 100 (FIG. 3) and, last,
suction hose 280 and clamp plate 165.
[0137] The trigger unit 240 is then placed, with its rightward
(FIG. 2) pivot stub 243 located in the corresponding boss 244 in
the rightward housing part 15, and its arm 251 inserted through the
hole 252 (FIG. 4A) into the interior of the handle portion of the
rightward housing part 15, as seen in FIGS. 4 and 4A. The trigger
arm 251 is "covered" by the rear portion 281 of the suction hose
280 in FIG. 3. The electrical contacts 262 and 263 are placed on
their respective posts 255 and 256 in the rear portion of the
rightward housing part 15 and the three forward electrical
connectors 175 are secured respectively to the mentioned contacts
262 and 263 and the motor contact 271 (FIG. 4A). Thereafter, the
leftward (FIG. 2) housing part 14 can be snap fitted to the
rightward housing part 15 to close same and enclose the above
mentioned apparatus, shown in FIG. 3, therein.
[0138] In the thus assembled handpiece, the drive unit is fixedly
located by engagement of its drive axis bosses 84 and 85 (FIG. 5)
in corresponding bosses in the housing parts 14 and 15 (see for
example at 96 in housing part 15 in FIG. 2). Location of the drive
unit 25 is assisted by the ribs 95 within the housing parts 14 and
15 and by snug resilient engagement of the drive unit 25 by the
hoses 160 and 280 which flank it.
[0139] The drive unit shell 26 is configured to maintain the proper
tolerances between meshing gears and related parts. Location of all
the drive unit parts in the drive unit shell 26 reduces the need to
maintain close tolerances in the larger and less specialized handle
housing 11. Even the housing tolerances, for locating the pump unit
100 with respect to the drive unit 25 in the housing 11, need not
be close since the bellows 101 are flexible enough to bend or
otherwise distort to absorb minor mis-alignment or angulation of
the reciprocation axis of the link member 51 with respect to the
length axis of the pump unit 100. Indeed, the ribs 95 in the
housing 11 permit pivoting of the drive unit 25 about the axis of
the bosses 96 to allow the drive unit 25 and pump unit 100 to
settle into their own working relative orientation. Accordingly,
the precision in the handpiece housing 11 can be concentrated in
aspects of fitting together of the two housing halves. The electric
power supply unit 190 (FIG. 22) is quickly and easily assembled.
More particularly, the feet of the respective battery contacts 210,
211, 212 (FIGS. 26-28) are slid downward into their respective
grooves (FIGS. 23A and 23B) in the pan 192 (FIG. 22) with their
protruding toes resiliently gripping the sides of the grooves. The
rear connectors 176 are connected to the battery contact fingers
224 and 225 in the order shown in FIG. 22A. The batteries B1-B8 are
then slipped down into the pan in the orientation shown in FIG. 22
and into electrically conductive engagement with the battery
contacts 210, 211 and 212 indicated in FIG. 22A. The rear portion
of the liquid hose 160 is laid atop the batteries as indicated in
FIG. 23, with the square flange 182 nonrotatable in the boss 235,
and the cover 193 is snap fitted atop the liquid hose 160 and
battery filled pan 192, as shown in FIG. 23, to complete assembly
of the power supply unit. The cap 185 is pressed onto the sharpened
tip 184 to protect it prior to use.
[0140] The result is a disposable pulsed irrigation handpiece unit
which is entirely self-contained, including its own power supply,
and which is ready for use upon having its sharpened tip 184
plugged into a conventional irrigation liquid supply bag or the
like, and a conventional manner.
[0141] It should be noted that virtually the entire handpiece 10
and power supply unit 190 can be assembled without need for any
adhesives, the parts going together with friction or snap fits or,
in the case of the joinder of the bellows housing 104 to the
bellows 100 and elbow 151, by being held together by surrounding
structure which in turn is snap fitted together. This greatly eases
and speeds assembly. A minor exception is that the fitting 180 is
here adhesively fixed to the hose 160.
[0142] To use the handpiece assembly in surgery, the cap 185 (FIG.
23) is removed from the pointed tip 183, which is then plugged into
a standard output fitting on a conventional irrigation liquid
supply bag. The power supply unit 190, being fixed to the rear end
of the irrigation liquid hose 160, can be allowed to simply hang
from the irrigation liquid supply bag (not shown but schematically
indicated at S in FIG. 22). By providing a substantial length of
irrigation liquid hose 160 (for example 10 feet), the liquid supply
bag S and power supply unit 190 can be located well out of the way
of the surgical team during use of the handpiece 10 at the surgical
site. Even then, the power supply unit 190 is compact as compared
to the adjacent conventional irrigational liquid supply bag (being
very little larger than the eight conventional double AA batteries
that it houses). If suction will be desired at the surgical site,
the handpiece nipple 283 (FIG. 3) can be connected by a
conventional hose not shown to a conventional suction source SS
(FIG. 3).
[0143] A variety of tip units 291 of differing characteristics
(e.g. differing irrigation liquid spray patterns, etc.) may be made
available for alternative mounting on the handpiece 10. One example
is shown in FIGS. 8, 8A and 8B.
[0144] In any event, the user selects a tip unit 291 having a wand
294 of desired configuration, and rearwardly inserts its coupling
292 into the front end of the handpiece 11. More particularly, the
nipples 301 and 306 of the tip unit are inserted coaxially
rearwardly, in sealed relation (see FIG. 8) in the conduits 143 and
286 respectively of the bellows housing 104. The resilient latch
arm 312 enters the barrel 13 of the handpiece housing 11 adjacent
to the bellows housing 104 until the plate 320 of the front cover
293 abuts the front end of the handpiece housing barrel 13. In the
last part of this tip installation movement, the wedge shaped ridge
313 (FIG. 8) on the latch arm 312 snaps past the rib 314 of the
housing barrel 13 to positively prevent forward removal of the tip
unit from the handpiece.
[0145] To use the apparatus for irrigation of a surgical site, the
user grips the handpiece, either by the handle 12, in a pistol-like
manner, or where the barrel 13 joins the handle 12, in a wand like
manner. In either position, the user has one or more fingers that
can bear on and press inwardly the trigger lever 242 from its
inoperative rest position shown in solid line in FIG. 4A forward
and through its low speed and high speed positions indicated in
broken lines at 253B and 253C in FIG. 4A. In the first operative
position 253B, the blade 253 connects the low speed (here six-volt)
contact 266 to the motor contact 270. On the other hand, in the
fully depressed condition of the trigger, indicated at 253C, the
blade 253 connects the high speed, 12 volt contact 267 with the
motor contact 270. Accordingly, the user can select between "off",
lower power pulsing and high power pulsing.
[0146] In one embodiment pump stroke was about 1/4''. In one
embodiment shown, the motor speed was about 15,000 rpm and the
speed reduction afforded by the transmission was about 15-1,
providing the eccentric with about 1,000 rpm speed.
[0147] Depending on the flow resistance of the particular tip unit
attached to the handpiece, the liquid pulse frequency may change.
In one example, a handpiece according to the invention produced
about 1200 pulses per minute, dispensing about 1600 ml per minute
of irrigation liquid in about 1.3 ml liquid pulses. The positive
drive of the pump unit by the drive unit and the location of the
pump unit, near the front end of the barrel 13 and in direct
engagement with the tip unit, provides liquid pulses at the output
of the tip unit which have sharp rise and fall slopes. Thus, the
relationship of liquid pulse amplitude to time approximates a
square wave form, more so than for example, the aforementioned
device of U.S. Pat. No. 5,046,486. Further, the force applied to
the pulses by the present apparatus is higher (somewhat above one
Newton) than in that prior art device, at the full power position
of the trigger.
[0148] In one embodiment according to the invention, a tab 316
(FIGS. 1 and 8B) extends forward from the front plate 320 of the
front cover 293, on the opposite side of the wand 294 from the
latch arm 312. To release the latch arm 312 from the housing 11,
the user can thus simply simultaneously grip with opposite fingers
and pinch toward each other the latch arm 312 and tab 316. In other
words the tab 316 provides base toward which to pinch, or pull, the
latch arm 312 to release the tip unit 291 from the handpiece
11.
[0149] In the present invention, the liquid and suction nipples of
the tip unit connect directly to the pump unit 100, and do not
contact any part of the handpiece housing 11. Accordingly, neither
the pump unit 100 nor tip unit 291 need fit with close tolerances
the handpiece housing 11. The connection of the tip unit to the
handpiece housing is merely to latch the tip unit against loss from
the handpiece housing and to casually cover the open front end of
the handpiece housing. Accordingly, the liquid tight fit is between
the nipples of the tip unit and conduits of the pump unit, not with
the housing.
[0150] Although a particular preferred embodiment of the invention
has been disclosed in detail for illustrative purposes, it will be
recognized that variations or modifications of the disclosed
apparatus, including the rearrangement of parts, lie within the
scope of the present invention.
* * * * *