JPH0470897B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an endoscope in which a treatment instrument is introduced into a body cavity through a treatment instrument insertion port through an insertion channel.

[Prior Art] Generally, an endoscope is provided with an insertion channel for introducing a treatment instrument such as forceps into a body cavity (for example, as disclosed in Japanese Patent Publication No. 63-29539 and Japanese Patent Publication No. 1
-Refer to Publication No. 40616). The passage on the treatment instrument insertion port side and the suction tube are connected to this insertion channel via a branch connection member.

By the way, since the treatment instrument insertion port is provided on the side of the operation section, the passage at the connection portion between the passage on the treatment instrument insertion port side and the insertion channel is a bent or curved portion. There is.

Therefore, when inserting the treatment instrument into the insertion channel from the treatment instrument insertion opening, the treatment instrument advances while bending along the bent or curved passage portion.

[Problems to be Solved by the Invention] As described above, in conventional endoscopes, when a treatment instrument is inserted from the treatment instrument insertion opening into the insertion channel via the branch connection member, the treatment instrument is inserted into the insertion channel at its bent portion. As it progresses while curving along the passage of
The tip of the treatment instrument rubs against the curved outer wall of the passageway. One end portion of a connecting tube for connecting a channel tube on the distal end side is concentrically fitted into the connecting hole of the branch connecting member and connected thereto.

For this reason, when the tip of the treatment instrument to be inserted into the insertion channel curves along the passage and advances while pressing against the wall surface on the outside of the curve of the passage, the distal end of the treatment instrument is inserted into the connecting hole of the branch connection member. It is easy to get caught on one end edge of the connected tube. In particular, the step at the boundary between the flexible tube and the distal end of the treatment instrument tends to get caught, impairing smooth insertion. Furthermore, there was a drawback that the treatment instrument could be damaged.

The present invention has been made focusing on the above-mentioned problems,
The purpose is to provide an endoscope with improved insertability when inserting a treatment instrument from a treatment instrument insertion opening through a connecting portion with a curved portion.

[Means and effects for solving the problems] In order to solve the above problems, the present invention provides an insertion channel for guiding a treatment instrument introduced from a treatment instrument insertion opening provided in an operating section, and a part of this insertion channel. A passage formed by a bending part formed in the bending part, a connecting part connecting a channel forming member provided near the bending part and forming the above-mentioned insertion channel, and a channel forming member on the distal end side of this connecting part. The endoscope is provided with a step formed by shifting an inner wall surface portion located on the outer side of the curved portion from the inner wall surface of the channel forming member on the proximal end side to the outer side of the curved portion.

Therefore, when the treatment instrument passes through the connecting part provided near the bend formed in the insertion channel, it curves along the bend, but corresponds to the outside of the bend in the passage. Since the wall surface is recessed with a step, the treatment instrument is less likely to get caught on the connecting part, and can be inserted smoothly.

[Embodiment] FIGS. 1 to 3 show an embodiment of the present invention.

As shown in FIG. 3, the endoscope 1 of this embodiment
consists of an operating section 2 and an insertion section 3, and the operating section 2
The main body 4 is composed of an operating section main body 4 formed into a substantially hollow spherical shape, a grip section 5 connected to the operating section main body 4, and a connecting section main body 6. The operation section main body 4 is provided with an eyepiece section 7, a bending operation lever 8, and a suction operation section 9. A long and thin flexible insertion section 3 is connected to the connection section main body 6. Note that a light guide cable (not shown) is connected to the operation section main body 4.

Furthermore, a pair of bending operation wires guided through a wire guide (not shown) are inserted into the insertion portion 3 . The proximal end of this bending operation wire is
It is guided into the operating section 2 and connected to a bending operation mechanism (not shown) installed in the operating section main body 4 via a guide wire (not shown). The bending operation mechanism is driven by operating the above-mentioned bending operation lever 8, and by pushing and pulling the pair of operation wires in opposite directions via the index wire, the distal end side portion of the insertion section 3 is operated. is forced to curve.

Further, a mounting base for mounting various operating mechanisms is installed inside the operating section main body 4, and a pair of frames 11 are connected to this mounting base, and this frame 11 and the mounting base are connected. It is covered with a cover 12 as a member. The cover 12 covers the operation section main body 4.
This outer peripheral portion forms a grip portion 5 to be held by the operator's hand. Further, the distal end portion of the cover 12 is formed as a portion having a slightly smaller diameter than the base portion thereof, and a branch main body 13 branched into a substantially Y-shape is integrally formed in this small diameter portion.

The pair of frames 11 fixed to the mounting base have main cylinder portions 13a in the branch main body 13.
The connecting portion main body 6 is connected to the distal end of the frame 11. That is, a connecting ring 15 is fixed to the frame 11 by a fixing screw 16a, and this connecting ring 1
A base portion 6a of the connecting portion main body 6 formed in a cylindrical shape is fitted into the connecting portion 5. The base 6a of the connecting portion main body 6 and the connecting ring 15 are connected by a fixing screw 16.
It is connected and fixed by b. Further, a flange 17 is integrally provided on the base 6a of the connecting portion main body 6, and two engaging recesses are symmetrically provided in this flange 17. Furthermore, an engagement protrusion that engages with the engagement recesses is integrally provided on the inner circumferential portion of the cover 12 that faces these engagement recesses. The engagement between the engagement recess and the engagement protrusion prevents the connection portion main body 6 and the cover 12 from rotating relative to each other in the circumferential direction.

Further, the distal end of the base 6a of the connecting portion main body 6 is formed into a tapered portion 18 whose inner diameter is tapered, and the insertion portion 3 is connected to this tapered portion 18. That is, the proximal end of the insertion tube 22 of the insertion section 3 is connected to the connecting tube 21 constituting the proximal end of the insertion section 3 . This connecting pipe body 2
A tapered surface 23 corresponding to the tapered portion 18 and a threaded portion 24 are formed on the outer circumferential surface of No. 1 . A tightening ring 25 that comes into contact with the end surface of the base 6a of the connecting portion main body 6 is screwed into the threaded portion 24, and the tightening force of the tightening ring 25 causes the connecting portion main body 6 and the connecting pipe body 21 to be connected together. are connected. Further, two engaging recesses 26 are symmetrically provided in the large diameter portion of the connecting tube body 21. Furthermore, an engagement protrusion 27 that engages with the engagement recess 26 is integrally provided on the inner peripheral portion of the connecting portion main body 6 facing the engagement recess 26 . The engagement between the engagement concave portion 26 and the engagement convex portion 27 prevents the connection portion main body 6 and the connection tube body 21 on the insertion portion 3 side from rotating relative to each other in the circumferential direction. Further, a fixed ring 28 is provided on the outer periphery of the distal end of the connecting portion main body 6.
are screwed together, and a bending tube body 29 is connected by this fixed ring 28. At this time, tightening ring 2
Even if a twisting force is applied to the connecting tube body 21 due to the tightening force of 5, the force is transmitted to the connecting body 6 by the engagement between the engaging recess 26 and the engaging protrusion 27. That is, due to the engagement with the connecting portion main body 6, rotation of the connecting tube body 21 in the circumferential direction is prevented, and the insertion portion 3 is prevented from rotating in the circumferential direction.
No torsional force is applied to the

Furthermore, a branch block 30 is fixedly provided inside the branch main body 13. This branch block 30 has first to third connecting holes 3 corresponding to the branch shape of the branch main body 13.
1, 32, and 33. These connecting holes 3
1, 32, and 33 communicate with each other through a substantially Y-shaped branch passage 34. A suction channel forming pipe 36 is provided in the first connecting hole 31.
A channel pipe 37 installed inside the insertion tube body 21 is connected to the second connection hole 32 . Further, the third connecting hole 33 is oriented in the same direction as the branching cylinder part 13b branched from the main cylinder part 13a in the branching part main body 13, and the third connecting hole 33 is provided with the base of the channel cap 38. The ends are connected. The middle part of this channel cap 38 is fixed to the open end of the branched cylinder part 13b by a fixing ring 39, and the tip part is fixed to the opening end of the branched cylinder part 13b.
It protrudes from the tip of. These constitute a treatment instrument insertion port on the side of the operating section 2.

The connecting portion between the second connecting hole 32 of the branch block 30 and the channel pipe 37 is particularly constructed as shown on an enlarged scale in FIG. That is, on the inner circumferential surface of the second connecting hole 32 of the branch block 30 as a channel forming member on the proximal end side, a fitting receiving hole portion 41 is provided eccentrically with respect to the axis of the second connecting hole 32. It is provided. This fitting receiving hole portion 41 is formed by grinding the inner surface of the second connecting hole 32, and is formed on the upper side of the extension line of the third connecting hole 33 (the area between the second connecting hole 32 and the third connecting hole 32). It is deep on the outside of the bend formed by 33 and shallow on the opposite side. Into the fitting receiving hole 41 thus formed, a fitting cylindrical portion 43 on the proximal end side of the connecting tube body 42 serving as a channel forming member on the distal end side is inserted. Moreover, the wall thickness of this fitting cylinder portion 43 is smaller than that of the deeper fitting receiving hole portion 41. Therefore, in the state of being fitted into the fitting receiving hole portion 41, a step a is formed between the inner surface of the second connecting hole 32 and the inner surface of the fitting cylinder portion 43. In other words, this step a is formed on the inner wall of the passage formed by the second connecting hole 32 of the branch block 30 and the inner hole of the connecting tube body 42.
It is formed by shifting the inner wall surface portion on the outside of the bend (outside the center of curvature) of the bend formed by curving from the third connecting hole 33 to the outside of the bend. That is, the distal end portion 46 of the treatment instrument 45 inserted from the channel mouthpiece 38, and the boundary portion 48 between the distal end portion 46 and the treatment instrument flexible tube 47.
It is structured so that it does not get caught easily and can be inserted smoothly.

Further, a threaded portion 51 is provided in the middle of the connecting tube 42, and a connecting portion 52 is provided at the tip of the connecting tube 42. The channel pipe 37 is fitted and connected to this connecting portion 52 . and,
This fitting connection portion is tightened and fixed by a nut 53 that is screwed into the threaded portion 51.

Therefore, in the endoscope 1 configured as described above, when the treatment instrument 45 is inserted through the channel cap 38, the distal end portion 46 of the treatment instrument 45 is introduced through the third connection hole 33, and The second connecting hole 32 advances along the inclination of the connecting hole 33, and then enters the inside of the connecting tube body 42, as shown in FIG.

Then, as described above, the connecting pipe body 42 is connected to the second
is mounted eccentrically above the extension line of the third connecting hole 33 with respect to the center of the connecting hole 32, and there is a step a between the inner surface of the second connecting hole 32 and the inner surface of the fitting cylinder part 43. , and the wall surface corresponding to the outside of the curved part of the passage was set aside as a step a.
Boundary portion 4 between the distal end portion 46 and the treatment instrument flexible tube 47
8 is less likely to get caught there. Therefore, the treatment instrument 45 can be inserted smoothly.

Note that the present invention is not limited to the above embodiments. Regarding the endoscope to which the present invention is applied, it is also possible to use a comparatively small diameter bronchial endoscope or an endoscope with a large diameter insertion section.

[Effects of the Invention] As explained above, according to the present invention, when the treatment instrument passes through the connecting portion provided near the bent portion formed in the insertion channel,
The tip of the treatment instrument curves along the bend, but the tip of the treatment instrument is retracted with a step on the wall corresponding to the outside of the bend in the passage, making it difficult for the treatment instrument to get caught in the connecting part. , it can be inserted smoothly. Moreover, the treatment instrument will not be damaged if it is pulled.

[Brief explanation of drawings]

1 to 3 show a first embodiment of the present invention, in which FIG. 1 is an enlarged sectional view of a part of the branch block, FIG. 2 is a vertical sectional view of the grip, and FIG. 3 is a connection. It is a longitudinal cross-sectional view of a part main body. 1... Endoscope, 2... Operation section, 3... Insertion section,
4... Operating unit main body, 30... Branching block, 32
...Second connection hole, 33...Third connection hole, 38
...Channel cap, 42...Connection pipe body, a...
Step.

Claims (1)

[Claims] 1. An insertion channel for guiding the treatment instrument introduced from the treatment instrument insertion opening provided in the operating section, a bent portion formed in a part of this insertion channel, and the insertion channel provided near this bent portion. A connecting part that connects channel forming members that form a channel, and an inner wall surface portion located on the outside of the bend in the passage formed by the channel forming member on the distal side of this connecting part as the channel on the proximal side. An endoscope comprising: a step formed by being shifted outward from the bending portion with respect to the inner wall surface of the forming member.