JPS644335Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention relates to the improvement of a high-frequency knife for an endoscope, which is inserted into an endoscope and used to perform treatment such as incision of an affected part in a living body cavity. It is something.

(Prior Art) As shown in FIG.
The endoscope S is inserted into the endoscope S so that it can be made to protrude toward the affected area from the hard tip portion H that constitutes the tip of the insertion portion I of the endoscope S. In this high-frequency knife K, an electrode wire is inserted into a flexible tube, and a pair of wire lead-out openings are bored at an interval in the axial direction at the tip of the tube. The structure is such that the electrode wire is led out of the tube at a portion between the sections. With this configuration, by pulling the electrode wire, the distal end of the tube is curved into an arch shape, and the electrode wire is stretched in a bow string shape between them, and in this state, a high-frequency current is applied to the electrode wire. It is now possible to supply it and perform treatments such as incision of the affected area.

When bending the electrode wire by pulling it, force is concentrated at the center of the curved part of the tube, and if the operation is repeated or if you accidentally pull with a larger force than necessary, the tube will There were disadvantages such as crushing and bending, and poor durability. For this reason, some devices are known in which the tube is protected by attaching reinforcing coils to the inner surface of the portion that is bent during operation.

(Problem to be solved by the invention) However, if the tube is reinforced by attaching a reinforcing coil to the tube as described above, not only will the number of parts increase, making manufacturing and assembly difficult. If the reinforcing coil has a loosely wound part and a tightly wound part, smooth bending operation may be hindered, or the tube may be crushed and bent at the boundary between the coarsely wound part and the tightly wound part. There were also some shortcomings.

The present invention was developed in view of the above points, and has a simple structure that prevents force from being concentrated in the center of the curved part of the tube when operating a high-frequency knife.
It is an object of the present invention to provide a high-frequency knife for an endoscope that is resistant to crushing and bending and has excellent durability.

(Means for solving the problem) In order to achieve the above-mentioned object, the high-frequency knife for an endoscope according to the present invention partially changes the wall thickness of the portion between the wire lead-out openings of the tube. In particular, the tube is characterized by a structure that allows it to be easily curved into an arch shape.

(Function) The high-frequency knife is inserted through the forceps port into the endoscope inserted into the body cavity, and is protruded from the hard part of the tip of the insertion part toward the affected area, and by pulling the electrode wire. The tip of the tube is in a bowed state. Then, in this state, a high-frequency current is passed through the electrode wire to incise the affected area.

Here, since the tip of the tube has a partially varied wall thickness, when the electrode wire is pulled, it smoothly curves into an arch shape, and a portion of the tube is partially curved in the center of the curved portion of the tube. This prevents excessive force from being applied to the Therefore, it has become possible to suppress the occurrence of tube bending accidents,
Durability as a high frequency knife is improved.

(Example) Hereinafter, an example of the present invention will be described in detail based on the drawings.

First, FIGS. 2 to 5 show a first embodiment of the present invention, and as shown in the figures, the high-frequency knife is made of a high-voltage insulating material and includes a flexible tube 1 and a flexible tube 1. Electrode wire 2 inserted into 1
It is roughly composed of. As shown in FIG. 2, the proximal end of the tube 1 is fixed to a connector 3, and the connector 3 is screwed onto a holding cylinder 4 made of an electrically insulating material. can be fitted into the forceps opening of the endoscope. Further, the electrode wire 2 inserted into the tube 1 is provided so as to pass through the holding cylinder 4, and is inserted into and fixed to a sliding rod 5 that is slidable with respect to the holding cylinder 4. It is connected to a connection terminal 6 to a power supply device.

On the other hand, two openings 7a and 7b for wire insertion are bored at the tip of the tube 1 at intervals in the axial direction, and the electrode wire 2 inserted into the tube 1 is inserted into these openings 7a and 7b. By leading the electrode wire 2 out of the tube 1 through the proximal opening 7a and reinserting it into the tube 1 through the distal opening 7b, only the portion between the openings 7a and 7b is inserted into the tube 1. It has been brought out to the outside. The tip of the electrode wire 2 is fixed by a retaining ring 8 fixedly provided inside the tube 1, as shown in FIG.

Furthermore, the opening 7 of the outer surface of the tube 1
a, 7b, that is, the part where the electrode wire 2 is led out of the tube 1, by cutting the part facing the electrode wire 2 in the axial direction to form a chamfered part 9. The wall thickness is made thinner than other parts. Moreover, this chamfered portion 9 is formed up to the drilling position of each opening 7a, 7b,
As soon as it passes through each opening 7a, 7b, it becomes the same thickness as the other parts.

This embodiment is configured as described above,
This high-frequency knife is used together with an endoscope and inserted into a living body cavity, and as shown in FIG. Treatment such as incision of the affected area is performed by flowing the water.

Here, since the portion between the openings 7a and 7b of the tube 1 has a partial wall thickness change as described above, when the tube 1 bends when the electrode wire 2 is pulled, the thin wall Since the parts are curved with a large curvature and the curvature of the thick parts is small, it can be curved smoothly and without difficulty.
There will be no inconveniences such as bending due to excessive force applied to some parts.

By the way, even if the openings 7a and 7b of the tube 1 are formed with a thin wall, as shown in FIG. They will not be cut open.

Next, FIGS. 6 to 8 show a second embodiment of the present invention, and in this embodiment, wire insertion openings 12a and 1 formed at the tip of the tube 11 are shown.
2b, the outer surface of the side facing the electrode wire 13 and the outer surface of the opposite side, that is, the part that is curved with the maximum curvature during the bending operation, and the part that is curved with the minimum curvature. A plurality of V grooves 14 are carved in each portion.
In this embodiment, this V-groove 14 has a width of 6 mm between the wire insertion openings 12a and 12b of the tube 11.
It is divided into equal parts, and two locations are formed near each opening.

Even with this configuration, the position where the V-groove 14 of the tube 11 is formed becomes a thin part, which causes a difference in wall thickness from other parts, and when the electrode wire 13 is pulled, the tube 11 becomes thin. This V groove 1
4, the tube 11 can be easily bent into an arch shape without causing stress concentration at the center of the curved portion, and the tube 11 can be reliably prevented from bending.

In each of the above-mentioned embodiments, the tube was shown to have a partially thinner wall, but the point is to have a change in wall thickness so that the tube can be easily and reasonably bent when the electrode wire is operated. For example, it may be partially thickened. Further, in the first embodiment, the chamfered portion 9 may be formed in a curved shape such that the portion in the axial direction facing the electrode wire 2 is thinnest. Furthermore, in the second embodiment, the side curved with a large curvature has a larger number of VVs than the opposite side.
A structure in which grooves are carved may also be used.

(Effects of the invention) As explained in detail above, the high-frequency knife for endoscopes according to the invention has a structure in which the wall thickness of the tube is partially changed. When curving the
The tube can be curved easily and smoothly, and no inconveniences such as bending occur. Furthermore, since there is no need to increase the number of parts, manufacturing and assembly are facilitated.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing a state in which a high-frequency knife is attached to an endoscope, FIGS. 2 to 5 show a first embodiment of the present invention, and FIG. 3 is an enlarged sectional view taken along the - line in FIG. 2, FIG. 4 is a sectional view taken along the - line in FIG. The figures show a second embodiment of the invention, FIG. 6 is a sectional view similar to FIG. 3, FIG. 7 is a cross-sectional view from FIG. 6, and FIG. FIG. 1, 11...tube, 2, 13...electrode wire, 7a, 7b, 12a, 12b...opening for wire insertion, 9...chamfer, 14...V groove.

Claims (1)

[Scope of utility model registration request] An electrode wire is inserted into a flexible tube, and a pair of wire lead-out openings are axially spaced apart from each other to lead the electrode wire out of the tube at the distal end of the tube. In the high-frequency knife for an endoscope, the distal end of the tube is curved in an arch shape by pulling the tube, and the wall thickness of the tube between the openings is adjusted so as to make it easier to curve the tube in an arch shape. A high-frequency knife for an endoscope, which is characterized by partially changing the above.