U.S. patent application number 13/269885 was filed with the patent office on 2012-04-12 for fluid ejection device and medical instrument.
This patent application is currently assigned to SEIKO EPSON CORPORATION. Invention is credited to Atsuya HIRABAYASHI, Hideki KOJIMA.
Application Number | 20120089164 13/269885 |
Document ID | / |
Family ID | 44993474 |
Filed Date | 2012-04-12 |
United States Patent
Application |
20120089164 |
Kind Code |
A1 |
KOJIMA; Hideki ; et
al. |
April 12, 2012 |
FLUID EJECTION DEVICE AND MEDICAL INSTRUMENT
Abstract
A fluid ejection device includes a pulsation generator which
converts a fluid into a pulsed fluid, a fluid supply unit (supply
pump) which supplies the fluid to the pulsation generator, an
ejection tube which has an ejection opening communicating with the
pulsation generator, a suction tube into which the ejection tube is
inserted with play, a suction channel provided between the suction
tube and the ejection tube, a suction opening provided at an end of
the suction channel in a vicinity of the ejection opening, and a
suction unit (suction pump) which sucks fluid in such a manner that
the fluid introduced from the suction opening passes through the
suction channel. The ejection opening is held by an inner
circumferential part of the suction opening. According to this
structure, vibration of the ejection tube in the vicinity of the
ejection opening can be reduced.
Inventors: |
KOJIMA; Hideki;
(Matsumoto-shi, JP) ; HIRABAYASHI; Atsuya;
(Chino-shi, JP) |
Assignee: |
SEIKO EPSON CORPORATION
Tokyo
JP
|
Family ID: |
44993474 |
Appl. No.: |
13/269885 |
Filed: |
October 10, 2011 |
Current U.S.
Class: |
606/167 |
Current CPC
Class: |
A61B 2217/007 20130101;
A61B 2217/005 20130101; A61B 2017/00154 20130101; A61B 17/3203
20130101 |
Class at
Publication: |
606/167 |
International
Class: |
A61B 17/3203 20060101
A61B017/3203 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 12, 2010 |
JP |
2010-229325 |
Claims
1. A fluid ejection device comprising: a pulsation generator which
converts a fluid into a pulsed fluid; a fluid supply unit which
supplies the fluid to the pulsation generator; an ejection tube
which has an ejection opening communicating with the pulsation
generator; a suction tube into which the ejection tube is inserted
with play; a suction channel provided between the inner
circumferential surface of the suction tube and the outer
circumferential surface of the ejection tube; a suction opening
provided at an end of the suction channel in a vicinity of the
ejection opening; and a suction unit which sucks the ejected fluid
in such a manner that the ejected fluid introduced from the suction
opening passes through the suction channel, wherein the ejection
opening is held by an inner circumferential part of the suction
opening.
2. The fluid ejection device according to claim 1, wherein a
cross-sectional shape of the suction opening in a direction
perpendicular to an extending direction of the suction tube is a
flat shape.
3. The fluid ejection device according to claim 1, wherein a
cross-sectional shape of the suction opening in a direction
perpendicular to an extending direction of the suction tube is a
substantially elliptic shape.
4. The fluid ejection device according to claim 1, wherein the
ejection opening is positioned substantially at a center of the
suction opening.
5. The fluid ejection device according to claim 1, wherein a tip of
the suction tube including the suction opening engages with the
suction tube in such a manner as to be rotatable around an axis of
the suction tube.
6. A medical instrument, comprising the fluid ejection device
according to claim 1.
7. A medical instrument, comprising the fluid ejection device
according to claim 2.
8. A medical instrument, comprising the fluid ejection device
according to claim 3.
9. A medical instrument, comprising the fluid ejection device
according to claim 4.
10. A medical instrument, comprising the fluid ejection device
according to claim 5.
11. A fluid ejection device comprising: a pulsation generator which
converts a fluid into a pulsed fluid; a fluid supply unit which
supplies the fluid to the pulsation generator; an ejection tube
which has an ejection opening communicating with the pulsation
generator; and a suction tube into which the ejection tube is
inserted, wherein a holding area formed in an end of the suction
tube is configured to hold the ejection tube, wherein the ejection
tube and the suction tube are configured to provide a suction
channel between the ejection tube and the suction tube, wherein a
suction opening to access the suction channel is formed in a
vicinity of a tip of the ejection tube.
12. The fluid ejection device of claim 11, wherein the holding area
has a cross sectional area that is substantially elliptical,
wherein the ejection tube is held at at least two points opposing
points of the corresponding to a position of a minor axis of the
cross sectional area.
13. The fluid ejection device of claim 11, wherein the holding area
has a cross sectional area that is substantially rectangular.
14. The fluid ejection device of claim 11, wherein the holding area
configured to rotate relative to the ejection tube.
Description
[0001] This application claims the benefit of Japanese Patent
Application No: 2010-229325, filed Oct. 12, 2010, which application
is expressly incorporated by reference herein.
BACKGROUND
[0002] 1. Technical Field
[0003] Embodiments of the present invention relate to a fluid
ejection device, and a medical instrument including the fluid
ejection device.
[0004] 2. Related Art
[0005] A fluid ejection device capable of excising, incising, and
crushing living tissue has excellent characteristics when used as a
surgical instrument. A low probability of heat damage and
preservation of blood vessels including capillaries are examples of
these characteristics.
[0006] During surgery, a surgery target may become obscured from
view while using the fluid ejection device. A certain type of fluid
ejection device has a suction tube which sucks and removes the
ejected liquid, excised tissue or the like remaining on the surgery
target so as to ensure that the surgery target remains visible
during surgery.
[0007] This type of fluid ejection device includes an ejection tube
through which high-pressure fluid is ejected. The ejection tube is
disposed within a suction channel of a suction tube in such a
position so as to be concentric with the suction channel (for
example, see JP-A-1-313047).
[0008] Another example of the fluid ejection device has an ejection
tube through which high-pressure fluid is ejected. This ejection
tube is inserted into a suction tube eccentrically with respect to
the inner circumferential surface of the suction tube (for example,
see JP-A-6-90957).
[0009] A further example of the fluid ejection device is equipped
with a volume varying unit which rapidly varies the volume of a
fluid chamber so as to convert the fluid into a pulsed fluid. The
fluid is thus ejected in pulses at high speed through an ejection
opening (for example, see JP-A-2008-82202).
[0010] According to the fluid ejection devices disclosed in
JP-A-1-313047 and JP-A-6-90957, however, the ejection tube vibrates
when fluid is ejected in pulses at high speed when using the
technology disclosed in JP-A-2008-82202. More specifically, the
ejection tube provided within the suction tube is not supported or
fixed except at the root of the ejection tube. As a result,
vibrations occur at the tip of the ejection tube when fluid is
ejected in pulses at high speed. Several problems arise from the
vibrations that occur at the tip of the ejection tube. For example,
there is a decrease in the positional accuracy of the fluid
ejection. In addition, vibration noise is generated by the
interference between the ejection tube and the suction tube into
which the ejection tube is inserted.
[0011] To overcome these problems, a structure has been adopted
which includes a support member within the suction tube to firmly
support the ejection tube. However, this structure is complicated.
In addition, this structure deteriorates the maneuverability of the
fluid ejection device due to the increased size and weight of the
fluid ejection device resulting from this structure.
SUMMARY
[0012] An advantage of some aspects of embodiments the invention is
to solve at least a part of the aforementioned problems.
Embodiments of the invention can be implemented according to the
following forms or application examples.
Application Example 1
[0013] This application example is directed to a fluid ejection
device including: a pulsation generator which converts fluid into a
pulsed fluid; a fluid supply unit which supplies the fluid to the
pulsation generator; an ejection tube which has an ejection opening
communicating with the pulsation generator; a suction tube into
which the ejection tube is inserted with play; a suction channel
provided between the inner circumferential surface of the suction
tube and the outer circumferential surface of the ejection tube; a
suction opening provided at the end of the suction channel in the
vicinity of the ejection opening; and a suction unit which sucks
the fluid in such a manner that the fluid introduced from the
suction opening passes through the suction channel. The ejection
opening is held by an inner circumferential part of the suction
opening.
[0014] According to this application example of the invention, the
ejection opening of the ejection tube is held by the inner
circumferential part of the suction tube. In this case, the tip of
the ejection tube does not easily vibrate during high-speed
ejection of pulsed fluid. In the case of the fluid ejection device
which has the ejection tube inserted into the suction tube with
play provided therebetween (e.g., between the ejection tube and the
suction tube), both an increase in the positional accuracy of the
fluid ejection and a reduction of abnormal noise can be achieved by
a simple structure without increasing the size and weight of the
fluid ejection device.
Application Example 2
[0015] This application example of the invention is directed to the
fluid ejection device of the above application example. In this
application example, a cross-sectional shape of the suction opening
in the direction perpendicular to the extending direction of the
suction tube is a flat shape.
[0016] According to this application example of the invention, the
cross-sectional shape of the suction opening has a flat shape or a
flattened shape. In one example, the cross-sectional shape of the
suction opening or the tip of the suction tube may be flatter than
another portion of the suction tube. In this case, the suction
opening can be sufficiently opened under the condition in which the
ejection tube is held by the inner circumferential surface of the
suction tube. The flat shape of the suction opening, for example,
maybe expanded upon insertion of the ejection tube, which
sufficiently opens the suction opening for sucking. Moreover, the
suction tube having the flat portion in the vicinity of the suction
opening (tip portion of the ejection tube) can be easily inserted
into a narrow surgery target portion, which further improves the
maneuverability of the fluid ejection device.
Application Example 3
[0017] This application example of the invention is directed to the
fluid ejection device of the above application example. In this
application example, across-sectional shape of the suction opening
in the direction perpendicular to the extending direction of the
suction tube is a substantially elliptic shape.
[0018] According to this application example of the invention, the
cross-sectional shape of the suction opening has a substantially
elliptic shape. In this case, a sufficient opening area of the
suction opening can be produced. The portion corresponding to the
major axis of the elliptic shape of the suction opening under the
condition in which the ejection tube is held by the portion of the
suction opening corresponding to the minor axis of the elliptic
shape of the suction opening provides the opening area. Moreover,
the suction tube having a flat shape formed by the elliptic shape
in the vicinity of the suction opening can be easily inserted into
a narrow surgery target portion, which further improves the
maneuverability of the fluid ejection device. Furthermore, the
suction opening having the substantially elliptic shape is not
easily caught by the surgery target portion. Even when the suction
opening contacts the surgery target portion, the surgery target
portion is not damaged thereby.
Application Example 4
[0019] This application example of the invention is directed to the
fluid ejection device of the above application example. In this
application example, the ejection opening is positioned
substantially at a center of the suction opening.
[0020] According to this application example of the invention, the
ejection opening is positioned substantially at the center of the
major axis of the suction tube. Thus, the position of the ejection
opening is easily recognized, which facilitates ejection of the
fluid toward the surgery target portion.
Application Example 5
[0021] This application example of the invention is directed to the
fluid ejection device of the above application example. In this
application example, the tip of the suction tube including the
suction opening engages with the suction tube in such a manner so
as to be rotatable around the axis of the suction tube.
[0022] According to this application example of the invention, the
tip of the suction tube is rotatable around the axis of the suction
tube. In this case, the direction of the tip of the suction tube
can be controlled in accordance with the shape of the surgery
target portion. Thus, the maneuverability of the fluid ejection
device further improves.
Application Example 6
[0023] This application example of the invention is directed to a
medical instrument including the fluid ejection device of the above
application example of the invention.
[0024] A medical instrument including the fluid ejection device of
the above application example of the invention can effectively
provide excellent characteristics of a surgery instrument.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] Embodiments of the invention will be described with
reference to the accompanying drawings, wherein like numbers
reference like elements.
[0026] FIG. 1 illustrates a structure of a fluid ejection device
according to a first embodiment.
[0027] FIG. 2A is a side cross-sectional view showing example
structures of a pulsation generator, an ejection tube, and a
suction tube according to a first example.
[0028] FIG. 2B is a perspective view showing an example of the tip
structure of the ejection tube and the suction tube.
[0029] FIG. 2C is a front view showing examples of the tips of the
ejection tube and the suction tube as viewed from the tip side (E
direction in FIG. 2A).
[0030] FIG. 3A is a perspective view showing an example of a tip
structure of an ejection tube and a suction tube according to a
second example.
[0031] FIG. 3B is a cross-sectional view taken along a line A-A in
FIG. 3A.
[0032] FIG. 4A is a front view showing examples of tips of an
ejection tube and a suction tube as viewed from the tip side
according to a third example.
[0033] FIG. 4B is a front view showing examples of tips of an
ejection tube and a suction tube as viewed from the tip side
according to a fourth example.
DESCRIPTION OF EXEMPLARY EMBODIMENT
[0034] Embodiments according to the invention are hereinafter
described with reference to the drawings. Scales different from the
actual ones are set for components and parts shown in the
respective figures so that these components and parts can be
expanded to sufficient sizes easily recognizable in the
figures.
First Embodiment
[0035] FIG. 1 illustrates a structure of a fluid ejection device
according to a first embodiment. In this embodiment, a fluid
ejection device included in a medical instrument will be discussed.
The fluid ejection device in this embodiment includes, but is not
limited to, functions such as excision, incision, exfoliation, and
crushing. further, the fluid ejection device is not limited to
applications in the medical field.
[0036] As illustrated in FIG. 1, a fluid ejection device 1 includes
a fluid supply container 2 storing fluid, a supply pump 10 as a
fluid supply unit, a pulsation generator 20 which converts fluid
supplied from the supply pump 10 into pulsed fluid, an ejection
tube 70 which communicates with the pulsation generator 20, a
suction tube 80 which extends from the pulsation generator 20, a
suction pump 11 as a suction unit, and a waste fluid container 3
which stores sucked waste liquid and excised tissue. The pulsation
generator 20, the supply pump 10, and the fluid supply container 2
are connected with one another via a fluid supply channel tube 4.
The suction tube 80, the suction pump 11, and the waste fluid
container 3 are connected with one another via a suction channel
tube 5.
[0037] The pulsation generator 20 may be constituted by any type of
generator that can eject fluid in pulses. Examples include a
piezoelectric type and a bubble jet type. In this embodiment, the
pulsation generator 20 includes a piezoelectric type generator.
Fluid used herein may be physiological salt water as an example,
although other fluids are within the scope of the disclosure. The
ejection tube 70 includes an ejection channel 71 communicating with
a fluid chamber 60 formed within the pulsation generator 20, and an
ejection opening 72 disposed at a tip of the ejection tube 70. The
ejection opening 72 maybe configured as an opening having a reduced
flow channel width.
[0038] The ejection tube 70 is inserted into the suction tube 80
with play provided therebetween. The ejection tube 70 may be held
by a part of the inner circumferential surface of the suction tube
80 in the vicinity of the ejection opening 72. The space formed
between the inner circumferential surface of the suction tube 80
and the outer circumferential surface of the ejection tube 70
corresponds to or defines a suction channel 81. A suction opening
82 is provided at the end of the suction channel 81 in the vicinity
of the ejection opening 72. In one example, the ejection tube 70 is
rigid enough to not be deformed by fluid pressure produced at the
time of fluid ejection. The suction tube 80 is rigid enough to not
be deformed by negative pressure produced by the suction pump
11.
[0039] The flow of fluid produced by the fluid ejection device 1 as
constructed is now briefly explained. Fluid stored in the fluid
supply container 2 is sucked by the supply pump 10, and supplied to
the pulsation generator 20 via the fluid supply channel tube 4 at
constant pressure in one embodiment.
[0040] The pulsation generator 20 includes the fluid chamber 60, a
piezoelectric device 30 as a volume varying unit which varies the
volume of the fluid chamber 60, and a diaphragm 40. The pulsation
generator 20 actuates the piezoelectric device 30 to generate a
pulsed flow within the fluid chamber 60. This pulsed flow passes
through the ejection channel 71, and comes out of the ejection
opening 72 as a high-speed ejection flow in pulses.
[0041] When the pulsation generator 20 stops operation, that is,
does not change the volume of the fluid chamber 60, the fluid
supplied from the supply pump 10 at constant pressure passes
through the fluid chamber 60 and comes out of the ejection opening
72 as a continuous ejection flow.
[0042] The pulsed flow of fluid herein refers to a flow of fluid
whose flow direction is kept constant or substantially constant and
whose flow amount or flow speed changes periodically or
irregularly. The pulsed flow includes an intermittent flow that
repeatedly flows and stops. However, the pulsed flow may include
other types of flow as long as the flow amount or flow speed of
fluid changes periodically or irregularly.
[0043] Similarly, the ejection of fluid in pulses refers to the
ejection of fluid whose flow amount or moving speed varies
periodically or irregularly. The ejection of fluid in pulses
includes an intermittent ejection which repeats the ejection and
non-ejection of fluid, for example. However, the ejection in pulses
may include other types of ejection as long as the flow amount or
moving speed of fluid to be ejected changes periodically or
irregularly.
[0044] The suction mechanism is now explained. The fluid ejected
from the ejection opening 72 remains on the surgery target portion
as waste liquid. Moreover, excised living tissue (hereinafter
abbreviated as excised tissue) stays on the surgery target portion
as well. The waste liquid and excised tissue are sucked by the
suction pump 11 through the suction opening 82, and passed though
the suction channel 81 and the suction channel tube 5 to be stored
in the waste fluid container 3. The operation of the suction pump
11 may be initiated in correlation with the operation of the
pulsation generator 20. Alternatively, the suction pump 11 may be
intermittently operated at regular intervals, or only operated as
necessary.
[0045] There are several shapes and structures of the ejection tube
70 and the suction tube 80 considered as appropriate examples. The
details of these shapes and structures are hereinafter described as
specific examples in conjunction with the associated drawings.
First Example
[0046] FIG. 2A is a side cross-sectional view of the pulsation
generator, the ejection tube, and the suction tube according to the
first example taken along a plane extending in the flow direction
of the fluid. FIG. 2B is a perspective view illustrating a tip
structure of the ejection tube and the suction tube. FIG. 2C is a
front view illustrating example tips of the ejection tube and the
suction tube as viewed from the tip direction (direction of E in
FIG. 2A).
[0047] As illustrated in FIG. 2A, the pulsation generator 20
includes an inlet channel 61 through which fluid supplied from the
supply pump 10 via the fluid supply channel tube 4 is introduced
into the fluid chamber 60. The pulsation generator 20 also includes
the piezoelectric device 30 and the diaphragm 40 as the volume
varying unit for varying the volume of the fluid chamber 60, and an
outlet channel 62 communicating with the fluid chamber 60.
[0048] The diaphragm 40 is formed by a disk-shaped metal thin plate
in this example, and is fixed by close contact with a lower case 50
and an upper case 52. The piezoelectric device 30 is a laminated
piezoelectric device in this example. One of the ends of the
piezoelectric device 30 is fixed to the diaphragm 40 via an upper
plate 35, while the other end of the piezoelectric device 30 is
fixed to a bottom plate 51.
[0049] The liquid chamber 60 is a space produced between the
diaphragm 40 and a recess formed on the surface of the upper case
52 opposed to the diaphragm 40. The outlet channel 62 is opened
substantially at the center of the fluid chamber 60 in this
example.
[0050] The upper case 52 and the lower case 50 are joined to each
other via the opposed faces thereof to be formed into one body (in
the example shown in FIG. 2A, the diaphragm 40 is interposed
between the cases 52 and 50). The ejection tube 70 may be inserted
into the upper case 52 by press-fit. The ejection tube 70 includes
the ejection channel 71 which communicates with the outlet channel
62. The ejection opening 72 may have a reduced channel diameter and
is opened at the tip of the ejection tube 70. The ejection opening
72 may be provided as a nozzle.
[0051] The suction tube 80 provided as a jacket tube of the
ejection tube 70 extends from the upper case 52. An opening 83 is
formed in the vicinity of the root end of the suction tube 80 on
the side close to the pulsation generator 20 in such a manner as to
penetrate the tube wall of the suction tube 80. The suction channel
tube 5 attached to the opening 83 communicates with the opening
83.
[0052] According to this structure, the extending direction of the
suction channel tube 5 in the vicinity of the pulsation generator
20 is equalized with the direction of the fluid supply channel tube
4. In this case, the maneuverability of the fluid ejection device 1
improves when the ejection device 1 is used by an operator
(operator of the ejection device) who holds the pulsation generator
20 during operation of the fluid ejection device 1. The ejection
tube 70 and the suction tube 80 may be tubes extending in straight
lines. However, the tubes 70 and 80 may be bent as illustrated in
FIG. 2A so that visibility around the ejection opening 72 can be
secured without the hand and fingers of the operator holding the
fluid ejection device 1 impeding visibility around the ejection
opening 72.
[0053] As illustrated in FIGS. 2B and 2C, the tip of the ejection
tube 70 in the vicinity of the ejection opening 72 is held by a
flat part of the inner circumferential surface of the suction tube
80. More specifically, the cross section of a holding area L of the
suction tube 80 in the vicinity of the suction opening 82 has a
substantially elliptic shape having a major axis Dh and a minor
axis Dv such that two points of the ejection tube 70 opposed to
each other approximately in the direction of the diameter can be
held by the part of the suction tube 80 corresponding to the
position of the minor axis Dv.
[0054] While the suction tube 80 has a flat shape produced by the
substantially elliptic cross section in this example, the direction
of flatness is not limited to this direction. For example, the
suction tube 80 may have a substantially elliptic shape which has
the major axis Dv and the minor axis Dh. In addition, while only
the tip portion of the suction tube 80 has the substantially
elliptic shape in this example, the entire shape as well as the tip
portion of the suction tube 80 may be substantially elliptic when
at least the part of the ejection tube in the vicinity of the
ejection opening is held by the inner circumferential part of the
suction tube.
[0055] The suction channel 81 and the suction opening 82 are formed
by the space between the outer circumference of the ejection tube
70 and the inner circumference of the suction tube 80. In this
case, as illustrated in FIGS. 2B and 2C, the space corresponding to
the suction channel 81 and the suction opening 82 in the holding
area L becomes wider as the major axis Dh of the substantially
elliptic cylindrical shape of the suction tube 80 increases. When
the two points of the ejection tube 70 opposed to each other
approximately in the direction of the diameter are held by the part
of the suction tube 80 corresponding to the position of the minor
axis Dv, substantially the same opening area is produced in the
suction opening 82 on each side of the ejection opening 72. In
other words, the ejection opening 72 is positioned substantially at
the center of the major axis Dh in one example.
[0056] The ejection tube 70 can be fixed to the suction tube 80 by
applying an adhesive, a solder or other fixing materials to the
portion of the inner circumference of the suction tube 80 holding
the outer circumference of the ejection tube 70. Alternatively, the
ejection tube 70 may be held and fixed by pressing and deforming
the portion of the suction tube 80 corresponding to the holding
area L such that this portion becomes a flat portion after the
ejection tube 70 is inserted into the suction tube 80 with play
provided between the ejection tube 70 and the suction tube 80. The
length of the holding area L may be arbitrarily determined as long
as the ejection tube 70 can be securely held and fixed by the
length of the holding area L. Thus, the holding area L may be
provided only at the tip of the ejection tube 70.
[0057] According to the fluid ejection device in this example, the
following advantages can be offered.
[0058] The area of the ejection tube 70 in the vicinity of the
ejection opening 72 can be easily held and fixed without using an
additional support member provided within the suction tube 80.
According to this structure, at least two points of the ejection
tube 70 opposed to each other in the direction of the diameter can
be held by the suction tube 80, in which condition the ejection
tube 70 can be more firmly fixed.
[0059] Since the area of the ejection tube 70 around the ejection
opening 72 is held by the suction tube 80 in one example, vibration
at the tip of the ejection tube 70 can be reduced during a
high-speed ejection of a pulsed flow. Thus, even in the case of the
fluid ejection device having the structure in which the ejection
tube 70 is inserted into the suction tube 80 with play provided
therebetween, a high-speed ejection of fluid in pulses toward the
surgery target position can be accurately achieved. Moreover, in
the condition where the outer circumference of the ejection tube 70
is directly held by the inner circumference of the suction tube 80,
abnormal noise, which might be generated due to vibration by the
contact between the ejection tube 70 and the suction tube 80, is
not generated.
[0060] The cross section of the portion of the suction tube 80
corresponding to the holding area L has a substantially elliptic
shape in one example. Thus, when the major axis Dh of the suction
tube 80 is long, the suction tube 80 obtains a sufficient opening
area of the suction opening 82 while holding and fixing the
ejection tube 70. In other words, the suction opening 82 of the
suction tube 80 is sufficiently open to enable suction.
[0061] The portion of the suction tube 80 in the holding area L has
the flat shape corresponding to the elliptic cross-sectional shape.
In this case, the fluid ejection device 1 can be easily inserted
into a narrow surgery target portion such as an incision target and
an exfoliation target. Thus, the maneuverability of the fluid
ejection device 1 during surgery is further improved.
[0062] The ejection opening 72 is disposed substantially at the
center of the major axis Dh of the suction tube 80. Accordingly,
the operator can easily recognize the position of the ejection
opening 72 and can easily operate the fluid ejection device 1 to
eject fluid toward the surgery target.
[0063] According to this example, therefore, vibration of the
ejection tube 70 and abnormal noise generated thereby can be
reduced by a simple structure without increasing the size and
weight of the fluid ejection device 1. Further, fluid can be
accurately ejected from the fluid ejection device 1 toward an
accurate target position. The maneuverability of the fluid ejection
device 1 is improved.
Second Example
[0064] A second example is now described with reference to the
drawings. FIG. 3A is a perspective view illustrating an example of
a tip structure of the ejection tube and the suction tube according
to the second example. FIG. 3B is a cross-sectional view taken
along a line A-A in FIG. 3A. According to the first example, the
suction tube 80 is constituted by a single piece structure. In this
example, however, the tip portion of the suction tube 80 is a
component that can be separated from the suction tube 80 and that
engages with the suction tube 80 in such a manner as to be
rotatable around the axis of the suction tube 80. Components and
parts in this example which correspond to similar components and
parts in the first example have been given similar reference
numbers, and the same explanation is not repeated.
[0065] As illustrated in FIG. 3A, the suction tube 80 has a tip
portion 80b, and a suction tube portion 80a extending between the
pulsation generator 20 and the tip portion 80b. The tip portion 80b
engages with the suction tube portion 80a.
[0066] The tip portion 80b includes the area corresponding to the
holding area L, and a joint 80bj which can be inserted into the
suction tube 80a for engagement therewith and sliding thereon in
such a manner as to be rotatable. The tip portion 80b also includes
an engaging portion provided between the holding area L and the
joint 80bj. In the engaging portion, the minor axis Dv of the
substantially elliptic cylinder gradually increases to produce a
substantially circular shape.
[0067] The joint 80bj is a cylindrical component constituting an
engaging portion between the tip portion 80b and the suction tube
portion 80a. The joint 80bj extends from the end of the tip portion
80b on the side contacting the suction tube portion 80a. The outer
circumference of the joint 80bj contacts the inner circumference of
the engaging area of the suction tube portion 80a and slides
thereon in such a manner as to be rotatable. The tip portion 80b
can be rotated with respect to the suction tube portion 80a.
Stoppers 80bt and 80bk are provided on the extended portion of the
joint 80bj. The stopper 80bt is a part for preventing the tip
portion 80b from being excessively inserted into the suction tube
portion 80a by the negative pressure produced by the suction pump
11. The stopper 80bk is a part for preventing separation of the tip
portion 80b from the engagement with the suction tube portion 80a.
A notch 80ak corresponding to the shape of the stopper 80bk is
provided on the suction tube portion 80a. When the tip portion 80b
is inserted in the suction tube portion 80a, the notch 80ak engages
with the stopper 80bk.
[0068] The outer circumference of the joint 80bj slides on the
inner circumference of the suction tube portion 80a, and the area
of the outer circumference of the ejection tube 70 corresponding to
the holding area L slides on the inner circumference of the tip
portion 80b. As a result, the tip portion 80b can rotate with
respect to the suction tube portion 80a around the axis thereof.
According to the first example, a fixing material such as an
adhesive and a solder is applied to the portion where the outer
circumference of the ejection tube 70 is held by the inner
circumference of the suction tube 80. In this example, however,
such a fixing material is not applied to this area to allow sliding
and/or rotation of the tubes 70 and 80 relative to each other. The
tip portion 80b can slide in at least a rotational motion. The
fluid ejection device in this example can provide at least the
following advantages. According to this structure, the tip portion
80b is rotatable with respect to the suction tube portion 80a
around the axis thereof.
[0069] In one example, the operator can control the direction of
the suction opening in accordance with the shape of the surgery
target portion. More specifically, the direction of the tip portion
80b having a flat shape can be varied (e.g., by rotating the tip
portion 80b) according to the shape of a narrow surgery target
portion such as an incision target, or changed in such a direction
that the surgery target portion can be easily seen.
[0070] Accordingly, the fluid ejection device in this example can
offer an advantage of further improvement over the maneuverability
of the fluid ejection device as well as the advantages provided in
the first example.
Third Example
[0071] A third example is now described with reference to the
drawings. FIG. 4A is a front view of example tips of the ejection
tube and the suction tube according to the third example as viewed
from the tip side (direction of E in FIG. 2A). According to the
first and second examples, the suction tube 80 has a substantially
elliptic cross section in the holding area L (FIG. 2C). However,
the cross section in each of the tips may have a shape of a suction
tube 80v shown in FIG. 4A. Components and parts in this example
which correspond to similar components and parts in the above
examples have been given similar reference numbers, and the same
explanation is not repeated.
[0072] The suction tube 80v has a flat shape produced by further
pressing the suction tube 80 having the substantially elliptic
shape in the first and second examples against the ejection tube
70. The suction tube 80v holds the ejection tube 70 via the surface
of the suction tube 80v extending almost along the curvature of the
outer circumference of the ejection tube 70. In this example,
approximately half the area of the outer circumferential surface of
the ejection tube 70 in the holding portion (holding area L) is
held by the inner circumference of the suction tube 80v.
[0073] According to this example, therefore, the suction tube 80v
can more firmly hold the ejection tube 70. The suction tube 80v is
pressed flat to shape a portion of the suction tube 80v against
more of the outer circumferential surface of the ejection tube 70
than previous examples. The suction tube 80v thus follows the shape
of the ejection tube 70. Moreover, the suction tube 80v has a more
flat shape and can be easily inserted into a narrower surgery
target portion such as an incision target or an exfoliation target,
which improves the maneuverability of the fluid ejection device
during surgery.
Fourth Example
[0074] A fourth example is now described with reference to the
drawings. FIG. 4B is a front view of example tips of the ejection
tube and the suction tube according to the fourth example as viewed
from the tip side. The cross-sectional shape of the suction tube 80
in the holding area L according to each of the first and second
examples may have a shape of a suction tube 80w shown in FIG. 4B.
Components and parts in this example which correspond to similar
components and parts in the above examples have been given similar
reference numbers, and the same explanation is not repeated.
[0075] The tip of the ejection tube 70 in the vicinity of the
ejection opening 72 is held by the inner circumference of the
suction tube 80w having a flat shape. More specifically, the cross
section of the suction tube 80w in the holding area L has a
substantially rectangular shape in this example. The length of the
short side of the rectangular shape is substantially equivalent to
the outside diameter of the ejection tube 70 being held. The
centers of the two long sides of the suction tube 80w substantially
hold two points of the ejection tube 70 opposed to each other in
the direction of the diameter. Each of the four corners of the
cross section of the substantially rectangular shape has a round
shape for protecting the surgery target in contact with the suction
tube 80w in one example.
[0076] According to this example, the width of the suction tube 80w
in the vicinity of the suction opening 82 is equivalent to each of
the corresponding widths of the suction tube 80 (FIG. 2C) and the
suction tube 80v (FIG. 4A). However, the opening area of the
suction opening 82 becomes wider due to the rectangular cross
section. Thus, the fluid and the excised tissue can be further
efficiently sucked and removed through the suction tube.
[0077] Medical Instrument
[0078] A medical instrument including the fluid ejection device 1
described herein can more effectively provide excellent
characteristics of a surgery instrument. More specifically, the
fluid ejection device 1 has excellent characteristics as a surgery
instrument including low probabilities of heat damage and
preservation of blood vessels including capillaries at the time of
excision, incision, crush and the like of living tissue. Both the
pulsed flow ejection which allows execution of surgery by using a
small amount of physiological salt water, and the provision of the
suction tube 80 around the ejection tube 70 can help prevent the
fluid and excised tissue from blocking the vision of an operator of
the fluid ejection device, thereby securing visibility for surgery.
The position of the ejection tube 70 substantially at the center of
the suction tube 80 allows the operator to easily recognize the
position of the ejection opening 72 and allows the operator to
easily eject fluid toward the surgery target accurately. The tip
portion of the ejection opening 72 under the held and fixed
condition does not vibrate during high-speed fluid ejection in
pulses, which permits the high-speed pulsed fluid ejection to be
directed toward the position of the surgery target with accuracy.
Moreover, elimination of abnormal noise generated with vibration
allows the operator to concentrate his or her attention further on
the surgery.
* * * * *