JPS6238132A - Bent tube of endoscope - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention [Field of Application in IR Industry] This invention relates to an endoscope used for observing the inside of a living body cavity or a machine, and in particular, it relates to an endoscope that is used to observe the inside of a living body cavity or a machine. This invention relates to an improvement of a curved tube of an endoscope in which the two are rotatably connected.

[Prior Art] Conventionally, the curved tube of an endoscope generally has a shape as shown in Fig. 5.
A plurality of joint rings b, each having pairs of shaft holes a formed at both ends facing each other in the diametrical direction, are rotatably connected by a connecting shaft C. An insertion tube d made of a pipe member is provided on the inner peripheral surface of the ring b so as to match the direction in which the shaft hole a is bored, and an operating wire e is provided.
, one end of which was placed on the nodal ring on the distal end side, and passed through the insertion tube d described in 1 to the rear.

[Problems to be Solved by the Invention] In the curved tube of the conventional endoscope mentioned above, the shaft hole a... is a simple circular hole as shown in Fig. 5, so the connecting shaft C...
In order to prevent the puller from falling out of the shaft hole a..., the head If... is thicker than the diameter of the shaft hole a... and the node ring b...
It was provided so as to protrude inward from the inner peripheral surface of... Therefore, the operating wire e... comes into contact with its protruding connecting shaft head f..., increasing the operating resistance of the operating wire e... and impairing the operability, or the operating wire e...
and the corner of the connecting shaft head f... and the bending causes the operating wire e to ride on the connecting shaft head f, as is clear from FIG. There is a problem in that the operation wire e is likely to be damaged or broken at an early stage due to repeated lifting and sliding movements.

Many proposals have been made to solve these problems.1 For example, the head of the connecting shaft protruding from the inner circumferential surface of the joint ring is enlarged, and a kite hole is bored there through which the operating wire is passed. There is (Utility Model Application Publication No.-137888).

However, in this case, when the connecting shaft is crimped, the pressure will deform the kite hole, which increases the resistance to the movement of the operating wire, making it difficult to obtain smooth operability. It did not fundamentally solve the problem.

The present invention solves these conventional problems and provides an endoscope in which the operation wire and the connecting shaft head do not come into contact with each other, so that the operation wire can be pulled easily and the wire is not damaged or broken. The purpose is to provide curved pipes.

[Means for Solving the Problems] 1-In order to achieve the above object, the curved tube of the endoscope of the present invention has a pair of axial holes formed at the 1114 end thereof, facing each other in the diametrical direction. A connecting shaft that is inserted through the shaft holes of the adjacent joint rings and rotatably connects each joint ring, and one end is fixed to the joint ring on the tip side. In the curved tube of the endoscope, the operating wire is drawn backward through each nodal ring. The head of the connecting shaft is formed in a tapered shape along the shape of the inner shaft hole, and the connecting shaft is inserted from the inside of the shaft hole toward the outside.

[Operation] Since the head of the connecting shaft does not protrude inward from the inner circumferential surface of the joint ring, when the operating wire is towed, the operating wire advances and retreats without contacting the head of the connecting shaft.

[Embodiment] An embodiment of the present invention will be described based on FIGS. 1 to 3.

FIG. 2 shows the overall configuration of the endoscope main body 1. The endoscope main body 1 includes an operating section 2, a light source connecting section 3 connected to the operating section 2 and connected to a light source device (not shown), and an operating section 2. It is composed of a lJ flexible insertion section 5 which is connected to the tip section 2 and has a tip body 4 with a built-in objective optical system attached to its tip.
A curved portion 6 that can be bent in the negative direction and in one left and right direction is formed at the tip of the , and the operating portion 2 has a bending operation knob 7.7.
is provided.

FIG. 3 and FIG. 1 show the structure of the above-mentioned curved section 6, and this curved section 6 is composed of a plurality of nodal rings 8 rotatably connected.

That is, the node ring 8... is a short cylindrical tube, and at each end thereof, a pair of connecting parts 9... are arranged diametrically opposite each other and at positions shifted by 90 degrees between the two ends. A shaft hole 10 is formed in the central part of each projection.
is drilled.

The connecting portions 9 of the adjacent nodal rings 8.8 are stacked inside and outside so that the respective shaft holes 10 are aligned coaxially with each other, and as shown in detail in FIG. The inner shaft hole 10 has a tapered portion 10a whose diameter gradually becomes smaller from the inside toward the outside, and a tapered portion 10b is formed on the smaller diameter side of the shaft hole 10. There is. Further, the outer shaft hole 10 is formed with a hole 10c having a smaller diameter than the diameter of the running portion 10b of the inner shaft hole 10, and the outer opening of the hole 10c is cut out. Nodal ring 8 like this...
For example, a stainless steel plate is formed into a predetermined shape by etching, etc., and after drilling is performed, it is rolled into a tube shape, and the ends are joined by a width similar to the thickness of the plate and welded by spont welding. A tubular nodal ring is obtained.

The connecting shaft 11 is inserted into the shaft hole 10 so that its head 11b does not protrude inward from the inner circumferential surface of the node ring 8, and is inserted from the inside to the outside. The connecting shafts 11... are made up of a shaft portion 11a that fits loosely into the shaft hole 10, and a head portion 11b formed in a shape that follows the tapered portion 10a of the shaft hole 10. After inserting it into the hole lO..., caulk its tail part 11c from the outside to prevent it from falling out of the connecting shaft 11... or shaft hole 10..., and then insert the joint ring 8... Rotatably connected.

12... are operating wires zl, and one end of these operating wires 12... The I-
A pulley or rank is drawn backward through the insertion portion 5 through the inside of the head 11b of each of the tracing shafts 11, and is connected to the bending operation knob 7.7 in the operation portion 2. It is connected to a small wire pulling device such as a pinion, and by rotating the bending operation knob 7°7, the operation wire 12...
- can be pulled to bend the curved portion 6 in any direction. The 14 beams are made of strong rubber.

Note that optical fiber bundles and other built-in items are inserted into the node rings 8, but are not shown.

Since the curved tube of the endoscope of this embodiment is constructed as shown in -1-, each node ring 8 is rotatably and firmly connected by the connecting shaft 11. , connection shaft 11
Since the heads 11b of... do not protrude from the inner circumferential surface of the joint ring 8, even if the operating wires 12... are towed, the operating wires 12... will not touch the heads of the connecting shafts 11... Part 11b・
Do not come into contact with...

FIG. 4 shows a second embodiment of the present invention, in which the inner shaft hole 20 of the jointed shaft holes 20 may be formed of only the tapered portion 20a in this way, Furthermore, even if the head 21b of the connecting shaft 21 is formed into a spherical shape as described above so that the top protrudes a little from the inner circumferential surface of the node ring 8, the operating wire 12 can be attached to the head of the connecting shaft 2L. It does not contact the portion 21b and does not have any adverse effect on the movement of the operating wire 12.

[Effects of the Invention] According to the curved tube of the endoscope of the present invention, the operating wire does not come into contact with the head of the connecting shaft of the joint ring, so the towing operation of the operating wire is extremely light and smooth, and damage to the operating wire is prevented. No breakage occurs.

Furthermore, since the head of the connecting shaft does not protrude inward from the inner periphery of the nodal ring as in the conventional case, damage to optical fiber bundles and other built-in objects due to repeated bending is eliminated, and the space within the nodal ring is increased. Therefore, the diameter of the curved part can be made thinner to reduce the number of pieces to be given to the subject. Also, since the connecting shaft can be caulked from the outside as before during assembly, the assembly It has the advantage of being easy to work with and practical.

[Brief explanation of drawings]

FIG. 1 is an enlarged sectional view of a main part of a first embodiment of a curved tube of an endoscope according to the present invention, FIG. 2 is an overall perspective view of an endoscope implementing the present invention, and FIG. A cross-sectional view of the curved part of the embodiment, No.
Figure 4 is a cross-sectional view of the main part of the second embodiment of the curved tube of the undeveloped endoscope, and Figures 5 and 6 are cross-sectional views of the curved tube of the conventional endoscope. ...Curved portion 8...Node ring 10, 20...Shaft hole 11.21...Connection shaft flb, 21b...Head 12...Operating wire patent applicant Asahi Optical Industry Co., Ltd. Patent Attorney Kazuhiko Mitsui Figure 1 Figure 2 ゛21b

Claims (1)

[Scope of Claims] 1. A plurality of joint rings each having a pair of shaft holes at both ends facing each other in the diametrical direction; In a curved tube of an endoscope, the above-mentioned curved tube is composed of a connecting shaft that rotatably connects the nodal rings, and an operating wire that is fixed at one end to the nodal ring on the distal end side and is drawn backward through each nodal ring. The inner shaft hole of the overlapping shaft holes is formed into a tapered shape that gradually becomes smaller in diameter from the inside toward the outside, and the head of the connecting shaft is formed into a tapered shape that follows the shape of the inner shaft hole. A curved tube for an endoscope, characterized in that a connecting shaft is inserted from the inside of the shaft hole toward the outside. 2. The curved tube of an endoscope according to claim 1, wherein the head of the connecting shaft inserted into the shaft hole does not protrude from the inner circumferential surface of the node ring. 3. A pair of shaft holes drilled at one end of the node ring and a pair of shaft holes drilled at the other end are formed in directions shifted by 90 degrees. Curved tube of endoscope. 4. Claim 1 or 3, wherein the operating wire is passed through the inner side of each connecting shaft head to the rear.
The curved tube of the endoscope described in Section 2.