JP3057851B2 - Endoscope treatment instrument insertion channel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a treatment tool insertion channel for inserting a treatment tool such as forceps in an endoscope used for medical purposes or the like.

[0002]

2. Description of the Related Art Endoscopes are generally used to diagnose upper and lower digestive tracts and organs, to collect cells in the body,
It is used for performing operations such as hemostasis and removal of polyps and other treatments. For this purpose, the endoscope has an operation unit for an operator such as a doctor to grasp and operate,
It is composed of an insertion part to be inserted into a patient's body, and a connector part connected to a light source for illuminating the inside of the body and a device having an air / water supply function. The operating section is provided with an angle mechanism for controlling the distal end of the insertion section to be guided to a target site in the body, an introduction port for forceps and other treatment tools, and the like. The insertion portion includes an imaging unit, a cable connected to the imaging unit, a light guide fiber for internal illumination, a treatment tool insertion channel for guiding the treatment device,
A wire and the like for controlling a bending operation of an angle portion which constitutes a portion near the distal end of the air supply / water supply channel and the insertion portion by remote control are incorporated. Also, in the connector part,
A light guide fiber, an air / water supply tube, a cable, and the like are incorporated.

[0003] Of the above constructions, the treatment instrument insertion channel has an inner diameter of about 1 mm to 5 mm depending on the purpose, and a typical condition that the treatment instrument insertion channel must have is as follows. There are the following. First, when the insertion portion is bent, the insertion portion must have flexibility so as to bend following the bent portion. In particular, since the bending portion of the insertion portion is bent with an extremely small radius of curvature, at least in the bending portion of the treatment instrument insertion channel, the bending portion can be easily bent, and when the bending is released, it is ensured. Must be restored. Next, since the treatment tool is inserted into the treatment tool insertion channel, at least the inner surface of the treatment tool insertion channel must be smoothly slid in order to smoothly guide the treatment tool.
In addition, endoscopes must be chemically resistant because they are cleaned each time they are used. In short, the treatment instrument insertion channel has airtightness,
Watertightness, flexibility, kink resistance, shape retention, good slip,
Chemical resistance, cleaning disinfection, etc. are required.

The structure of a tube used as a treatment tool insertion channel requiring the above characteristics is as follows.
A structure in which a net formed by braiding metal fibers in a polymer material such as a synthetic resin or rubber is embedded is disclosed in, for example, JP-A-59-151933. By having such a configuration, the treatment instrument has a bending property and a restoring property when the bending is released, and by appropriately setting the members forming the inner layer and the members forming the outer layer as required. Good slipperiness, airtightness / watertightness, chemical resistance, etc. when inserted. In addition, since the strength is improved by the net, kink resistance, shape retention and the like are also improved.

[0005] Here, the insertion portion of the endoscope, due to its function,
It can be divided into a soft part, an angle part and a hard tip part. The flexible portion occupies most of the portion from the portion connected to the operating portion, the angle portion is connected to the distal end portion of the flexible portion, and the hard distal portion is connected to the distal end side of the angle portion. Here, the angle portion is curved in an arbitrary direction in order to direct the hard distal end portion in a desired direction.
For this purpose, wires for controlling the bending operation of the angle portion by remote control are provided at the up, down, left and right positions.
When these four wires are pushed and pulled by the remote control from the operation unit, the angle unit bends in the vertical and horizontal directions. The above-described treatment tool insertion channel is also inserted into the angle portion, and the distal end thereof is connected to a connecting pipe attached to the rigid distal end portion, and the distal end communicates with the treatment instrument passage formed in the rigid distal end portion. The treatment instrument insertion passage is opened as a treatment instrument outlet at the end face portion or the side face portion of the distal end hard portion.

[0006]

By the way, when the angle portion is operated to bend, the treatment tool insertion channel located in the angle portion also bends following the angle portion. Since the distal end is connected to the connection pipe, which is a hard member, the hardness rapidly changes from the flexible treatment instrument insertion channel to the hard connection pipe. In addition, in this angle portion, not only a simple bending in the vertical direction and the horizontal direction, but also a composite operation of bending in the horizontal direction in a state of being bent in the vertical direction, for example, may be performed. The treatment instrument insertion channel will be twisted. Therefore, the distal end hard portion of the treatment instrument insertion channel,
That is, the possibility of buckling or deformation of the connection portion to the hard pipe or the vicinity thereof increases.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art. It is an object of the present invention to provide a treatment instrument insertion channel having at least a portion connected to a hard distal end portion. An object is to ensure protection without buckling or deformation.

[0008]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention provides a tube made of a flexible polymer material provided at least in an angle portion of an insertion portion of an endoscope. A flexible tube in which a net formed by braiding metal fibers is embedded, and a plurality of spot weldings are performed on a portion of the net near the end on the side of the connecting portion to the hard distal end of the insertion portion. The feature is that it has done.

[0009]

A net is buried in the flexible tube constituting the treatment instrument insertion channel so as not to impair flexibility and to have kink resistance and shape retention. This net is made of metal fiber. Is formed by braiding a given wire with a predetermined number of holdings and the number of hits, and when the wires intersecting each other are fixed, the elasticity as a net is regulated, and the portion becomes hard. . Therefore, in the net, wires intersecting with each other at a plurality of locations in the length direction from the end portion on the side of the continuous portion to the distal end hard portion are fixed by spot welding. In addition, in order to make the hardness uniform in all directions, welding is performed at a plurality of positions in the circumferential direction, at least at three positions (however, when the bending direction of the angle portion is only one of the vertical and horizontal directions). Can be welded in two places). As a result, the vicinity of the connection portion to the distal end hard portion in the treatment instrument insertion channel becomes hard, so that the hardness does not suddenly change, and the strength of the portion is improved by spot welding, and buckling occurs. , Deformation and the like can be prevented.

Here, it is preferable that the above-mentioned change in hardness be continuous from the distal end portion of the flexible tube constituting the treatment instrument insertion channel. To do this,
What is necessary is just to change the welding pitch interval so that the spot welding portion in the length direction is the densest on the tip end side and gradually becomes rough. In the treatment tool insertion channel, a flexible tube having a net embedded therein is provided to the entire angle portion and to a position where it enters the flexible portion, and most of the flexible portion is formed of a tube having no net. In some cases, the two tubes are connected using a connecting pipe or the like. In this case, the same is applied to the end of the flexible tube that is connected to the tube on the soft part side. Spot welding can be performed.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings. First, FIG. 1 shows a cross section near the distal end portion of the insertion section in the endoscope. In the figure, the internal components other than the treatment instrument insertion channel, that is, the light guide, the image guide (in the case of an electronic endoscope, a signal cable provided in place of the image guide), the air supply / water supply pipe, etc. Internal components are omitted.

As is apparent from FIG. 1, an angle portion 3 is connected to the distal end of the flexible portion 2 constituting the insertion portion 1, and a hard end portion 4 is connected to the angle portion 3. ing. In the drawings, the angle portion 3 and the distal end hard portion 4 are shown in a simplified manner. The treatment instrument insertion channel 5 is divided into two portions, and the portion up to a position near the portion where the flexible portion 2 is connected to the angle portion 3 is formed by a first flexible tube 6. The second flexible tube 6 has the second
Flexible tube 7 is connected. The connecting portions are connected by a hard connecting pipe 8 made of metal or plastic. A treatment tool insertion passage 9 is provided inside the distal end hard portion 4, and a hard connection pipe 10 made of metal, plastic, or the like is attached to the treatment tool insertion passage 9. The flexible tube 6 is connected to the connecting pipe 10. The connection structure between the first flexible tube 6 and the second flexible tube 7 may be performed by using any suitable means other than the above, for example, by directly connecting both flexible tubes. Can be.

Here, the first flexible tube 6 is made of, for example, a fluorine resin or other polymer material. On the other hand, the second flexible tube 7 has a configuration as shown in FIG. That is, the second flexible tube 7 includes the inner layer 11 and the outer layer 12. Inner layer 1
Reference numeral 1 denotes a crystalline polymer resin formed of a thin film tube made of, for example, a fluororesin, so that when a treatment tool such as a forceps is inserted therein, slipping can be improved. . The outer layer 12 has a function for maintaining strength such as kink resistance and shape-retaining property. The outer layer 12 is formed by embedding a net 14 as a reinforcing layer in a urethane resin layer 13 as a thermoplastic resin. It is made to enter. Here, the net 14 has a spring property such as a hard stainless fiber, an amorphous metal fiber, a tungsten fiber, or the like, and is configured by braiding a hard metal fiber.

The net 14 is designed to have a sufficient shape holding ability even when bent at the maximum angle in the curved portion of the insertion portion. The braid is made of a hard stainless steel wire made of the above-mentioned element wire with 18 hits and 2 holdings. In addition, since the maximum angle of the angle portion 3 may have a radius of curvature of about 15 mm, the bias angle should be about 70 to 50 ° in order to easily bend even in this case. preferable. further,
The urethane resin layer 13 in which the net 14 is embedded must have a thickness capable of completely covering the net 14, and the first flexible tube 6 is curved.
In order to prevent the net 14 from becoming a resistance when it expands and contracts and to prevent distortion or the like, a soft material is suitably used.

Here, the second flexible tube 7 must have flexibility as a whole, but the tip portion, that is, the connecting portion side to the connecting pipe 10 is hardened to some extent, so that the second flexible tube 7 is sharply sharpened. It is necessary to protect the hardness so that it does not change. Moreover, it is preferable that the hardness changes continuously. For this purpose, the hardness of the net 14 constituting the second flexible tube 7 is changed by spot welding at appropriate places. That is, when the intersection of the wires constituting the net 14 is fixed by spot welding, expansion and contraction of the portion is restricted, and the hardness increases. And, the narrower the pitch interval of the spot welding portion becomes, the harder it becomes.

Therefore, as shown by reference numeral S in FIG. 3, welding is performed at the end portion of the net 14 at the closest density, and spot welding is performed so that the pitch interval of the welding portion gradually increases to a predetermined portion. Further, in order to make the second flexible tube 7 have the same hardness in any direction, three or more welding spots S are provided at substantially equal angular intervals in the circumferential direction. As described above, spot welding not only increases hardness but also improves strength. Accordingly, as a whole, the strength near the connection portion of the second flexible tube 7 to the connection pipe 10 is improved, and even if the angle portion 3 is greatly bent, the angle can be combined in both the vertical and horizontal directions. Even if the second flexible tube 7 is twisted, as in the case where it is operated, the deformation due to this torsion can be effectively absorbed between the welding spots S, and sufficient strength can be maintained. There is no possibility of bending or deformation.

Here, the net 14 is composed of the inner layer 11 and the outer layer 1.
2 is braided on the urethane resin layer 13 constituting a part of the wire 2, so that the spot welding is performed in order to be able to drive the wire into the intersection of the wires of the net 14 without fail. It is preferable to perform the laser welding with good performance.

The spot welding is performed not only on the portion of the second flexible tube 7 connected to the distal end hard portion 5 but also on the side of the second flexible tube 7 connected to the first flexible tube 6. You can also. In addition, although the treatment tool insertion channel 5 is configured to be divided into the first movable tube 6 and the second flexible tube 7, the whole configuration may be the same as that of the second flexible tube. Good. Further, in the case where the angle portion is configured to bend only in one of the vertical and horizontal directions, two or more spot weldings may be performed in the bending direction.

[0019]

As described above, the present invention is flexible.
Since the site near the end of the insertion part of the net buried in the tube made of a polymer material having a connection part to the rigid end of the tip side near the end is connected, when the angle part is curved, The stress is not concentrated on the connecting portion to the hard tip portion, and the shape holding ability of the portion is improved, and the occurrence of defects such as deformation and kink is prevented.
It becomes durable.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a configuration of a distal end portion in an insertion section of an endoscope.

FIG. 2 is an explanatory diagram of a configuration of a second flexible tube.

FIG. 3 is an explanatory view showing a welded portion to a net.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Insertion part 2 Soft part 5 Treatment tool insertion channel 6 1st flexible tube 7 2nd flexible tube 11 Inner layer 12 Outer layer 13 Urethane layer 14 Net S welding spot

Claims (2)

(57) [Claims] 1. A provided by positioned in the angle portion of the insertion portion of the at least the endoscope, the flexible tube is embedded a net formed by braiding metal fibers into a tube made of a polymer material having flexibility A treatment tool insertion channel for an endoscope, wherein a plurality of spot weldings are performed on a portion of the net near an end on the side of a connection portion of the insertion portion to the hard distal end portion. 2. The structure according to claim 1, wherein the spot welding pitch interval is formed such that an end on a side connected to the hard tip end is made dense, and gradually roughened from this end. Endoscope treatment instrument insertion channel.