U.S. patent application number 12/974911 was filed with the patent office on 2011-04-21 for endoscopic insertion aid, endoscopic system, and method of inserting insertion portion of endoscope into body cavity by use of endoscopic insertion aid.
Invention is credited to Hidenobu Kimura, Raifu MATSUI, Nobuyuki Matsuura, Seisuke Takase, Takatoshi Yoshida.
Application Number | 20110092770 12/974911 |
Document ID | / |
Family ID | 38695541 |
Filed Date | 2011-04-21 |
United States Patent
Application |
20110092770 |
Kind Code |
A1 |
MATSUI; Raifu ; et
al. |
April 21, 2011 |
ENDOSCOPIC INSERTION AID, ENDOSCOPIC SYSTEM, AND METHOD OF
INSERTING INSERTION PORTION OF ENDOSCOPE INTO BODY CAVITY BY USE OF
ENDOSCOPIC INSERTION AID
Abstract
An endoscopic insertion aid includes a tube member, a pipeline
and a plurality of balloons. The tube member allows an insertion
section of an endoscope to be inserted therethrough, and guides the
longitudinal movement of the insertion section. The pipeline is
provided in the tube member, and communicates with a
supply/discharge unit to supply a fluid to or discharge the fluid
from the distal end of the tube member. The balloons are disposed
on the outer periphery of the distal end of the tube member
longitudinally along the tube member, communicate with the
pipeline, and inflate/deflate in accordance with the
supply/discharge of the fluid via the pipeline. The balloon
disposed on the distal side of the tube member is inflated to have
an outside diameter larger than that of the balloon disposed closer
to the proximal side than the balloon disposed on the distal side
when the balloons are inflated.
Inventors: |
MATSUI; Raifu; (Hino-shi,
JP) ; Matsuura; Nobuyuki; (Hino-shi, JP) ;
Takase; Seisuke; (Hachioji-shi, JP) ; Kimura;
Hidenobu; (Hachioji-shi, JP) ; Yoshida;
Takatoshi; (Hachioji-shi, JP) |
Family ID: |
38695541 |
Appl. No.: |
12/974911 |
Filed: |
December 21, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11779601 |
Jul 18, 2007 |
|
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|
12974911 |
|
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Current U.S.
Class: |
600/115 |
Current CPC
Class: |
A61B 2017/22069
20130101; A61B 1/04 20130101; A61B 1/00154 20130101; A61B 1/00082
20130101; A61B 2017/22055 20130101 |
Class at
Publication: |
600/115 |
International
Class: |
A61B 1/00 20060101
A61B001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 1, 2006 |
JP |
2006-210066 |
Claims
1. An endoscopic insertion aid comprising: a tube member which
allows an insertion section of an endoscope to be inserted
therethrough and which guides the longitudinal movement of the
insertion section; a pipeline which is provided in the tube member
and which communicates with a supply/discharge unit to supply a
fluid to the distal end of the tube member or discharge the fluid
from the distal end of the tube member; a plurality of balloons
which are disposed at the distal end of the tube member
longitudinally along the tube member and which communicate with the
pipeline and which inflate/deflate in accordance with the
supply/discharge of the fluid via the pipeline; and a regulator
configured to regulate so that a balloon disposed on the distal
side of the tube member is inflated to have an outside diameter
larger than that of a balloon disposed closer to the proximal side
of the tube member when the plurality of balloons are inflated,
wherein the regulator is arranged so that the length from the
distal end to proximal end of the balloon disposed on the distal
side of the tube member is larger than the length from the distal
end to proximal end of the balloon closer to the proximal side of
the tube member.
2. The endoscopic insertion aid according to claim 1, wherein the
regulator is arranged so that the same material is used for the
plurality of balloons and so that the thickness of the balloon
disposed on the distal side of the tube member is smaller than the
thickness of the balloon disposed closer to the proximal side of
the tube member.
3. The endoscopic insertion aid according to claim 1, wherein the
balloon disposed on the distal side among the plurality of balloons
is formed of a material having an expansion rate higher than that
of the balloon disposed closer to the proximal side of the tube
member.
4. The endoscopic insertion aid according to claim 1, wherein the
pipeline includes: a connection pipeline connected to the
supply/discharge unit which supplies/discharges the fluid to/from
the plurality of balloons; and a plurality of balloon communication
pipelines which branch from the connection pipeline to communicate
with the plurality of balloons and which supply/discharge the fluid
to/from the plurality of balloons, the balloon communication
pipeline communicating with the balloon disposed on the distal side
of the tube member among the balloon communication pipelines being
less resistant to the fluid than the balloon communication pipeline
communicating with the balloon disposed closer to the proximal side
of the tube member.
5. The endoscopic insertion aid according to claim 1, wherein the
cross-sectional area of the balloon communication pipeline
communicating with the balloon disposed on the distal side of the
tube member among the balloon communication pipelines is larger
than the cross-sectional area of the balloon communication pipeline
communicating with the balloon closer to the proximal side of the
tube member.
6. An endoscopic insertion aid comprising: a tube member which
allows an insertion section of an endoscope to be inserted
therethrough and which guides the longitudinal movement of the
insertion section; a pipeline which is provided in the tube member
and which communicates with a supply/discharge unit to supply a
fluid to the distal end of the tube member or discharge the fluid
from the distal end of the tube member; a plurality of balloons
which are disposed at the distal end of the tube member
longitudinally along the tube member and which communicate with the
pipeline and which inflate/deflate in accordance with the
supply/discharge of the fluid via the pipeline; and regulating
means for regulating so that the balloon disposed on the distal
side of the tube member is inflated to have an outside diameter
larger than that of the balloon disposed closer to the proximal
side of the tube member when the plurality of balloons are
inflated, wherein the regulating means are arranged so that the
same material is used for the plurality of balloons and so that the
thickness of the balloon disposed on the distal side of the tube
member is smaller than the thickness of the balloon disposed closer
to the proximal side of the tube member.
7. The endoscopic insertion aid according to claim 6, wherein the
balloon disposed on the distal side among the plurality of balloons
is formed of a material having an expansion rate higher than that
of the balloon disposed closer to the proximal side of the tube
member than the balloon disposed on the distal side.
8. The endoscopic insertion aid according to claim 6, wherein the
pipeline includes: a connection pipeline connected to the
supply/discharge unit which supplies/discharges the fluid to/from
the plurality of balloons; and a plurality of balloon communication
pipelines which branch from the connection pipeline to communicate
with the plurality of balloons and which supply/discharge the fluid
to/from the plurality of balloons, the balloon communication
pipeline communicating with the balloon disposed on the distal side
of the tube member among the balloon communication pipelines being
less resistant to the fluid than the balloon communication pipeline
communicating with the balloon disposed closer to the proximal side
of the tube member.
9. The endoscopic insertion aid according to claim 6, wherein the
cross-sectional area of the balloon communication pipeline
communicating with the balloon disposed on the distal side of the
tube member among the balloon communication pipelines is larger
than the cross-sectional area of the balloon communication pipeline
communicating with the balloon closer to the proximal side of the
tube member.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Divisional of U.S. application Ser.
No. 11/779,601 filed Jul. 18, 2007 and is based upon and claims the
benefit of priority from prior Japanese Patent Application No.
2006-210066, filed Aug. 1, 2006, the entire contents of which are
incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to an endoscopic insertion aid for
facilitating insertion by aiding in the insertion of an insertion
section of an endoscope into a region such as the large intestine
where insertion is difficult, an endoscopic system, and a method of
inserting the insertion section of the endoscope into a body cavity
by use of the endoscopic insertion aid.
[0004] 2. Description of the Related Art
[0005] For example, an endoscopic insertion aid having a plurality
of balloons at its distal end is disclosed in Jpn. Pat. Appln.
KOKAI Publication No. 10-155733. In this endoscopic insertion aid,
the inner wall of a body cavity is expanded outward by the balloons
to pull the aid to a hand side so that the aid is fixed to the
inner wall of the body cavity. Then, for example, bent parts or
twisted parts of the intestinal wall become substantially straight,
thereby permitting the improvement of the insertability of an
insertion section.
BRIEF SUMMARY OF THE INVENTION
[0006] An endoscopic insertion aid according to this invention
includes: a tube member, a pipeline and a plurality of balloons.
The tube member allows an insertion section of an endoscope to be
inserted therethrough, and guides the longitudinal movement of the
insertion section. The pipeline is provided in the tube member, and
communicates with a supply/discharge unit to supply a fluid to the
distal end of the tube member or discharge the fluid from the
distal end of the tube member. The plurality of balloons are
disposed on the outer periphery of the distal end of the tube
member longitudinally along the tube member, communicate with the
pipeline, and inflate/deflate in accordance with the
supply/discharge of the fluid via the pipeline. The balloon
disposed on the distal side of the tube member is inflated to have
an outside diameter larger than that of the balloon disposed closer
to the proximal side of the tube member than the balloon disposed
on the distal side when the plurality of balloons are inflated.
[0007] An endoscopic insertion aid according to this invention
includes: a tube member, a pipeline, a plurality of balloons and
regulating means. The tube member allows an insertion section of an
endoscope to be inserted therethrough, and guides the longitudinal
movement of the insertion section. The pipeline is provided in the
tube member, and communicates with a supply/discharge unit to
supply a fluid to the distal end of the tube member or discharge
the fluid from the distal end of the tube member. The plurality of
balloons are disposed at the distal end of the tube member
longitudinally along the tube member, communicate with the
pipeline, and inflate/deflate in accordance with the
supply/discharge of the fluid via the pipeline. The regulating
means operates so that the balloon disposed on the distal side of
the tube member is inflated to have an outside diameter larger than
that of the balloon disposed closer to the proximal side of the
tube member than the balloon disposed on the distal side when the
plurality of balloons are inflated.
[0008] Advantages of the invention will be set forth in the
description which follows, and in part will be obvious from the
description, or may be learned by practice of the invention.
Advantages of the invention may be realized and obtained by means
of the instrumentalities and combinations particularly pointed out
hereinafter.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0009] The accompanying drawings, which are incorporated in and
constitute a part of the specification, illustrate embodiments of
the invention, and together with the general description given
above and the detailed description of the embodiments given below,
serve to explain the principles of the invention.
[0010] FIG. 1 is a schematic diagram showing an endoscopic system
according to a first embodiment of the present invention;
[0011] FIG. 2 is a schematic longitudinal sectional view showing an
overtube in the endoscopic system according to the first
embodiment;
[0012] FIGS. 3A to 3D are schematic diagrams showing a procedure
for inserting an insertion section of an endoscope into the large
intestine by use of the endoscopic system according to the first
embodiment;
[0013] FIGS. 4A to 4D are schematic diagrams showing a procedure
for inserting the insertion section of the endoscope into the large
intestine by use of the endoscopic system according to the first
embodiment;
[0014] FIG. 5 is a schematic longitudinal sectional view showing an
overtube in an endoscopic system according to a second embodiment
of the present invention;
[0015] FIG. 6 is a schematic longitudinal sectional view showing an
overtube in an endoscopic system according to a third embodiment of
the present invention;
[0016] FIG. 7 is a schematic longitudinal sectional view showing
the distal end of the overtube in the endoscopic system according
to the third embodiment of the present invention;
[0017] FIG. 8A is a schematic longitudinal sectional view showing
the distal end of an overtube in an endoscopic system according to
a fourth embodiment of the present invention;
[0018] FIG. 8B is a schematic transverse sectional view along the
8B-8B line in FIG. 8A; and
[0019] FIG. 8C is a schematic longitudinal sectional view showing
the distal end of the overtube in the endoscopic system according
to the fourth embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0020] A best mode of carrying out this invention will hereinafter
be described with reference to the drawings.
[0021] A first embodiment will be described using FIGS. 1 to
4D.
[0022] As shown in FIG. 1, an endoscopic system 10 includes an
endoscope 12, an overtube (insertion aid) 14, a light source unit
16, a video processor 18, a monitor 20, and a balloon control unit
(supply/discharge unit) 22.
[0023] The endoscope 12 includes an elongate insertion section 32,
and an operation section 34 provided at the proximal end of the
insertion section 32, and a universal cord 36 extending from the
operation section 34. The light source unit 16 is optically
connected to a connector 36a at the end of the universal cord 36.
Light emitted from the light source unit 16 exits from the distal
end of the insertion section 32 via the universal cord 36, the
operation section 34 and the insertion section 32. The video
processor 18 is further electrically connected to a connector 36b
at the end of the universal cord 36 extending in addition to the
above-mentioned connector 36a. The monitor 20 is electrically
connected to the video processor 18 via a cable 20a. Thus, when an
optical image of a specimen is picked up by a solid-state image
sensing device such as a CCD described later, its signal is
processed by the video processor 18, and the image of the specimen
picked up is displayed on the monitor 20.
[0024] The insertion section 32 includes a rigid distal portion 42,
a bending portion 44 capable of vertically and horizontally
bending, and a long and flexible tube portion 46.
[0025] The rigid distal portion 42 is disposed at a most distal
position of the insertion section 32. The rigid distal portion 42
is provided with a forceps opening communicating with an
illumination optical system, an observation optical system such as
the solid-state image sensing device, and a treatment tool
insertion channel, and also provided with a nozzle for supplying
air into a body cavity and water to an observation lens (neither
the forceps opening nor the nozzle is shown). The treatment tool
insertion channel communicates with a treatment tool insertion hole
(not shown) of the operation section 34.
[0026] The distal end of the bending portion 44 is coupled to the
proximal end of the rigid distal portion 42. The distal end of the
flexible tube portion 46 is coupled to the proximal end of the
bending portion 44. The distal end of the operation section 34 is
coupled to the proximal end of the flexible tube portion 46. That
is, the distal end of the operation section 34 is coupled to the
proximal end of the insertion section 32.
[0027] The operation section 34 is provided with a remote switch 52
for the remote control of the video processor 18, etc., and a
bending operation knob 54 rotated by an operator. When the bending
operation knob 54 is operated, the above-mentioned bending portion
44 of the insertion section 32 curves in directions to deviate from
the longitudinal axis of the flexible tube portion 46, for example,
vertically and horizontally.
[0028] As shown in FIG. 2, the overtube 14 includes a main body
(tube member) 62 disposed to cover the outer periphery of the
insertion section 32 of the endoscope 12, a grip 64 provided at the
proximal end of the main body 62, and first to third balloons 66a,
66b and 66c provided on the outer peripheral surface of the distal
end of the main body 62. In the main body 62 and the grip 64, a
balloon communication pipeline 68 is formed which communicates with
the first to third balloons 66a, 66b and 66c. The distal end of the
balloon communication pipeline 68 communicates with the first to
third balloons 66a, 66b and 66c. The proximal end of the balloon
communication pipeline 68 communicates with a connector 64a
provided in the grip 64.
[0029] A connection pipeline 70 is disposed between the overtube 14
and the balloon control unit 22. Connectors 70a and 70b are
provided at one end and the other end of the connection pipeline
70, respectively. The connector 70a at one end of the connection
pipeline 70 is connected to the connector 64a of the grip 64. The
connector 70b at the other end of the connection pipeline 70 is
connected to a connector 22a of the balloon control unit 22.
[0030] The balloon control unit 22 includes a pump 72 capable of
supplying/discharging (sucking) a gas, a control circuit 74 for
controlling the pump 72, and a remote controller 76 electrically
connected to the control circuit 74 via a connection cable 76a.
This remote controller 76 is provided with a stop button 78a, a
pressurization button 78b and a decompression button 78c. When the
stop button 78a is depressed, its signal is input to the control
circuit 74. Then, the control circuit 74 stops the operation of the
pump 72. When the pressurization button 78b is depressed, its
signal is input to the control circuit 74. Then, the control
circuit 74 operates the pump 72 so that the gas is supplied from
the connection pipeline 70 to the balloon communication pipeline 68
of the overtube 14. When the decompression button 78c is depressed,
its signal is input to the control circuit 74. Then, the control
circuit 74 operates the pump 72 so that the gas is discharged from
the connection pipeline 70 and the balloon communication pipeline
68 of the overtube 14.
[0031] As shown in FIGS. 1 and 2, for example, the three first to
third balloons 66a, 66b and 66c are disposed at the distal end of
the overtube 14. The balloons 66a, 66b and 66c are formed of, for
example, silicone rubber, latex rubber, or an elastic elastomer.
The balloons 66a, 66b and 66c communicate with each other through
the balloon communication pipeline 68 provided in the main body 62.
Further, the outside diameter of the first balloon 66a on the most
distal side when inflated is formed to be greater than the outside
diameter of the adjacent second balloon 66b when inflated.
Moreover, the outside diameter of the third balloon 66c adjacent to
the second balloon 66b is formed to be smaller than that of the
second balloon 66b when the second and third balloons 66b and 66c
are inflated.
[0032] It is to be noted that the balloons 66a, 66b and 66c are
formed of, for example, one cylindrical member. The distal end and
proximal end of this cylindrical member are fixed by being wound
and bound with, for example, threads 80 (see FIG. 7). Then, the
cylindrical member is wound and bound with the threads 80 at
appropriate two places so that the first to third balloons 66a, 66b
and 66c are formed. Further, an adhesive is applied to the parts
wound with the threads 80 for fixture. Thus, the first to third
balloons 66a, 66b and 66c are formed.
[0033] Next, the function of the endoscopic system 10 according to
this embodiment will be described using FIGS. 3A to 4D.
[0034] The insertion section 32 of the endoscope 12 is per anum
inserted into the large intestine C shown in FIG. 3A, and the main
body 62 of the overtube 14 is inserted.
[0035] As shown in FIG. 3B, the pressurization button 78b of the
remote controller 76 is depressed. A signal is input from the
remote controller 76 to the control circuit 74 via the connection
cable 76a. The control circuit 74 operates the pump 72 while
controlling the pump 72. Then, the balloons 66a, 66b and 66c of the
overtube 14 are inflated so that the intestinal wall is expanded
outward by the balloons 66a, 66b and 66c. At this point, for
example, the pump 72 is controlled by the control circuit 74 to
adjust the velocity and amount of a fluid (gas), thereby slowly
inflating the balloons 66a, 66b and 66c. Thus, the balloons 66a,
66b and 66c slowly expand the intestinal wall outward. Further, the
position of the overtube 14 is held to the large intestine C by
frictional force between the balloons 66a, 66b and 66c and the
inner wall of the intestine.
[0036] It is to be noted that the pressurization of the balloons
66a, 66b and 66c is automatically stopped when specified pressure
is reached. Alternatively, the stop button 78a is depressed and its
signal is input to the control circuit 74 before the specified
pressure is reached. The control circuit 74 stops the operation of
the pump 72.
[0037] When the balloons 66a, 66b and 66c of the overtube 14 are
inflated as shown in FIG. 3B, the intestinal wall is expanded
outward so that the distal side of the first balloon 66a is also
expanded. Thus, as shown in FIG. 3C, the insertion section 32 of
the endoscope 12 is moved to the inner side of the large intestine
C while the position of the overtube 14 is being held. At this
point, the bending portion 44 of the insertion section 32 is caused
to further project forward from the distal end of the main body 62
of the overtube 14.
[0038] Then, the bending operation knob 54 of the operation section
34 is operated to curve the bending portion 44 of the insertion
section 32, as shown in FIG. 3D. Thus, the large intestine C
deforms in an S-shape. Therefore, the large intestine C is held so
that it is substantially caught between the bending portion 44 of
the insertion section 32 of the endoscope 12 and the rigid distal
portion 42.
[0039] The decompression button 78c of the remote controller 76 is
operated to operate the pump 72, and the balloons 66a, 66b and 66c
of the overtube 14 are deflated, as shown in FIG. 4A. At this
point, the pump 72 is controlled by the control circuit 74 to
discharge the gas from the balloons 66a, 66b and 66c as fast as
possible. Then, it is possible to quickly move on to the next
operation.
[0040] As shown in FIG. 4B, the overtube 14 is moved to the inner
side along the insertion section 32 of the endoscope 12.
[0041] As shown in FIG. 4C, the balloons 66a, 66b and 66c of the
overtube 14 are inflated to expand the wall of the large intestine
C. In this case as well, the balloons 66a, 66b and 66c are slowly
inflated. Then, the position of the overtube 14 is fixed by the
balloons 66a, 66b and 66c.
[0042] As shown in FIG. 4D, the bending operation knob 54 of the
operation section 34 of the endoscope 12 is operated to make the
curved bending portion 44 of the insertion section 32 straight.
That is, the holding of the large intestine C by the bending
portion 44 of the insertion section 32 and the rigid distal portion
42 is released. Further, the overtube 14 and the insertion section
32 of the endoscope 12 are pulled together so that their relative
movement is prevented. Then, using the balloons 66a, 66b and 66c in
which the diameter is larger on the distal side and smaller on the
proximal side, the large intestine C is pushed out to the hand side
(anal side) by the proximal part of the third balloon 66c. In the
same manner, the large intestine C is pushed out to the hand side
by the proximal part of the second balloon 66b. Further, the large
intestine C is pushed out to the hand side by the proximal part of
the third balloon 66c. Then, the folds of the inner wall of the
large intestine C are hooked between the first balloon 66a and the
second balloon 66b, between the second balloon 66b and the third
balloon 66c and by the proximal part of the third balloon 66c.
Therefore, when the overtube 14 and the insertion section 32 of the
endoscope 12 are pulled together, the large intestine C is pulled
to the hand side and efficiently folded (shortened) because the
folds of the large intestine C are hooked by the balloons 66a, 66b
and 66c.
[0043] Furthermore, as shown in FIG. 3C, the insertion section 32
of the endoscope 12 is inserted into the inner side with respect to
the overtube 14. Subsequently, similar operation is carried out to
insert the distal end of the insertion section 32 into the inner
side of the large intestine C.
[0044] As described above, the following effects can be obtained
according to this embodiment.
[0045] The plurality of balloons 66a, 66b and 66c are provided at
the distal end of the overtube 14. Moreover, the diameter of the
first balloon 66a is larger than the diameter of the second balloon
66b, and the diameter of the second balloon 66b is larger than the
diameter of the third balloon 66c. Thus, the effect of hooking the
inner wall of the large intestine C with the balloons 66a, 66b and
66c can be increased when the large intestine C is folded onto the
anal side. Further, the area of contact with the intestinal wall in
folding the large intestine C can be large. Thus, the force of
fixing the balloons 66a, 66b and 66c to the wall of the large
intestine C can be increased.
[0046] In addition, while the use of the three balloons 66a, 66b
and 66c has been described in this embodiment, for example, two or
four balloons may also be used, and the suitable number of balloons
is selected.
[0047] Next, a second embodiment will be described using FIG. 5.
This embodiment is a modification of the first embodiment, so that
the same signs are assigned to the same members as those described
in the first embodiment, and these members are not described in
detail.
[0048] First to third balloons 66a, 66b and 66c are formed into,
for example, separate members, but are formed of the same material
at about the same thickness.
[0049] As shown in FIG. 5, balloon communication holes 68a, 68b and
68c of the balloons 66a, 66b and 66c communicating with a balloon
communication pipeline 68 have cross-sectional areas different from
each other. The cross-sectional area a of the first balloon
communication hole 68a providing communication between the first
balloon 66a and the balloon communication pipeline 68 is formed to
be the largest. The cross-sectional area .beta. of the second
balloon communication hole 68b providing communication between the
second balloon 66b and the balloon communication pipeline 68 is
formed to be smaller than that of the first balloon communication
hole 68a. The cross-sectional area .gamma. of the third balloon
communication hole 68c providing communication between the third
balloon 66c and the balloon communication pipeline 68 is formed to
be smaller than that of the second balloon communication hole
68b.
[0050] Thus, when a gas is introduced through the balloon
communication pipeline 68, the amount of gas flowing from the
second balloon communication hole 68b into the second balloon 66b
is greater than the amount of gas flowing from the third balloon
communication hole 68c into the third balloon 66c. Moreover, the
amount of gas flowing from the first balloon communication hole 68a
into the first balloon 66a is greater than the amount of gas
flowing from the second balloon communication hole 68b into the
second balloon 66b.
[0051] Therefore, the times for inflating the first to third
balloons 66a, 66b and 66c can be about the same. Then, it is
possible to prevent, for example, any one of the first to third
balloons 66a, 66b and 66c from being in an overpressurized state or
a low pressure state.
[0052] Furthermore, the inflation amounts of the balloons 66a, 66b
and 66c can be regulated by the cross-sectional areas .alpha.,
.beta. and .gamma. of the balloon communication holes 68a, 68b and
68c. That is, the relationships between the cross-sectional areas
.alpha., .beta. and .gamma. of the first to third balloon
communication holes 68a, 68b and 68c serve as means for regulating
the inflation amounts of the balloons 66a, 66b and 66c so that one
supply of gas causes the first balloon 66a to be inflated to the
largest outside diameter, the second balloon 66b to be inflated to
the second largest outside diameter, and the third balloon 66c to
be inflated to the third largest outside diameter.
[0053] Next, a third embodiment will be described using FIGS. 6 and
7. This embodiment is a modification of the first embodiment, so
that the same signs are assigned to the same members as those
described in the first embodiment, and these members are not
described in detail.
[0054] FIG. 7 shows first to third balloons 66a, 66b and 66c in a
magnified manner so that an overtube 14 shown in FIG. 6 is rotated
90 degrees around the axis of a main body 62.
[0055] As shown in FIG. 7, the length L.sub.1 from the distal end
to proximal end of the first balloon 66a is formed to be larger
than the length L.sub.2 from the distal end to proximal end of the
second balloon 66b. Further, the length L.sub.2 from the distal end
to proximal end of the second balloon 66b is formed to be larger
than the length L.sub.3 from the distal end to proximal end of the
third balloon 66c.
[0056] The length L.sub.1 from the distal end to proximal end of
the first balloon 66a is larger than the length L.sub.2 from the
distal end to proximal end of the second balloon 66b, such that the
space in the first balloon 66a can be larger. Thus, a greater
amount of fluid can be made to flow into the first balloon 66a than
into the second balloon 66b. Then, the outside diameter of the
first balloon 66a on the distal side can be larger than that of the
second balloon 66b on the proximal side. The same applies to the
relationship between the second balloon 66b and the third balloon
66c.
[0057] Thus, the inflation amounts of the balloons 66a, 66b and 66c
can be regulated by the relationships between the lengths L.sub.1,
L.sub.2 and L.sub.3. That is, the relationships between the lengths
L.sub.1, L.sub.2 and L.sub.3 of the first to third balloons 66a,
66b and 66c serve as means for regulating the inflation amounts of
the balloons 66a, 66b and 66c so that one supply of gas causes the
first balloon 66a to be inflated to the largest outside diameter,
the second balloon 66b to be inflated to the second largest outside
diameter, and the third balloon 66c to be inflated to the third
largest outside diameter.
[0058] Furthermore, the first to third balloons 66a, 66b and 66c
are formed of the same material but are different from each other
in thickness. The thickness t.sub.1 of the first balloon 66a is
formed to be smaller than the thickness t.sub.2 of the second
balloon 66b. The thickness t.sub.2 of the second balloon 66b is
formed to be smaller than the thickness t.sub.3 of the third
balloon 66c.
[0059] Therefore, the times for inflating the first to third
balloons 66a, 66b and 66c can be about the same. Then, it is
possible to prevent, for example, any one of the first to third
balloons 66a, 66b and 66c from being in an overpressurized state or
a low pressure state.
[0060] The first to third balloons 66a, 66b and 66c are formed of
the same material, and the thickness t.sub.1 of the first balloon
66a is formed to be smaller than the thickness t.sub.2 of the
second balloon 66b, and the thickness t.sub.2 of the second balloon
66b is formed to be smaller than the thickness t.sub.3 of the third
balloon 66c. Thus, the inflation amounts of the balloons 66a, 66b
and 66c can be regulated by the relationships between the
thicknesses t.sub.1, t.sub.2 and t.sub.3. That is, the
relationships between the thicknesses t.sub.1, t.sub.2 and t.sub.3
of the first to third balloons 66a, 66b and 66c serve as means for
regulating the inflation amounts of the balloons 66a, 66b and 66c
so that one supply of gas causes the first balloon 66a to be
inflated to the largest outside diameter, the second balloon 66b to
be inflated to the second largest outside diameter, and the third
balloon 66c to be inflated to the third largest outside
diameter.
[0061] In addition, the same material is used and thickness is
varied in the first to third balloons 66a, 66b and 66c so that
their inflation times may be substantially equal to each other in
this embodiment described above. However, the inflation times of
the balloons 66a, 66b and 66c can also be made substantially equal
to each other by setting these balloons at a substantially uniform
thickness but using materials of different expansion rates (the
first balloon 66a has the highest expansion rate and the third
balloon 66c has the lowest expansion rate). In this case, the
cross-sectional areas of the first to third balloon communication
holes 68a, 68b and 68c shown in FIG. 6 may be the same or different
from each other. The cross-sectional areas are properly set in
relation to the thickness and the material.
[0062] Furthermore, the first to third balloons 66a, 66b and 66c
can also be formed of one cylindrical member. This cylindrical
member is formed so that the thickness becomes linearly greater
from the distal side to the proximal side. Then, when the
cylindrical member is fixed by threads 80 at appropriate positions,
the positions of the balloons 66a, 66b and 66c are regulated. At
this point, the outside diameters of the first to third balloons
66a, 66b and 66c can also be about the same when the balloons 66a,
66b and 66c are in a deflated state. In this case, the first to
third balloons 66a, 66b and 66c are inflated when the
cross-sectional areas of the first to third balloon communication
holes 68a, 68b and 68c are the same. Then, the first balloon 66a is
inflated into the largest size and the second balloon 66b is
inflated into the second largest size because the first balloon 66a
is formed thinner than the second and third 66b and 66c and because
the second balloon 66b is formed thinner than the third balloon
66c. The third balloon 66c is formed at the largest thickness and
is therefore inflated less.
[0063] Next, a fourth embodiment will be described using FIGS. 8A
and 8B. This embodiment is a modification of the first embodiment,
so that the same signs are assigned to the same members as those
described in the first embodiment, and these members are not
described in detail.
[0064] As shown in FIG. 8B, each of first to third balloons 66a,
66b and 66c includes a pair of bags 82a and a pair of bands
82b.
[0065] As shown in FIG. 8A, first to fourth grooves 84a, 84b, 84c
and 84d are formed in the outer peripheral surface of a main body
62. The length L.sub.1 between the first and second grooves 84a and
84b is formed to be larger than the length L.sub.2 between the
second and third grooves 84b and 84c. The length L.sub.2 between
the second and third grooves 84b and 84c is formed to be larger
than the length L.sub.3 between the third and fourth grooves 84c
and 84d. In this case, the first balloon 66a is formed thinner than
the second balloon 66b, and the second balloon 66b is formed
thinner than the third balloon 66c.
[0066] Therefore, the times for inflating the first to third
balloons 66a, 66b and 66c can be about the same. Then, it is
possible to prevent, for example, any one of the first to third
balloons 66a, 66b and 66c from being in an overpressurized state or
a low pressure state.
[0067] Next, a modification of the fourth embodiment will be
described using FIG. 8C.
[0068] Among the grooves 84a, 84b, 84c and 84d shown in FIG. 8A,
the second groove 84b is used in common by the proximal side of the
first balloon 66a and the distal side of the second balloon 66b.
The third groove 84c is used in common by the proximal side of the
second balloon and the distal side of the third balloon 66c.
[0069] Conversely, grooves 92a, 92b, 94a, 94b, 96a and 96b shown in
FIG. 8C are separately provided. In this case, the positions of the
balloons 66a, 66b and 66c can be suitably set. That is, the
distance between the balloons 66a, 66b and 66c can be suitably
set.
[0070] Additional advantages and modifications will readily occur
to those skilled in the art. Therefore, the invention in its
broader aspects is not limited to the specific details and
representative embodiments shown and described herein. Accordingly,
various modifications may be made without departing from the spirit
or scope of the general inventive concept as defined by the
appended claims and their equivalents.
* * * * *