JP6809699B2 - Treatment tool - Google Patents

Description

The present invention relates to a treatment tool that is inserted into the body and used.

Conventionally, there are known treatment tools that are introduced into the body endoscopically, for example, and perform various treatments.
As one of the typical ones, a treatment tool having a treatment portion in which a pair of forceps members are rotatably connected is known. In such a treatment tool, an operation wire normally connected to the treatment unit extends to the operation unit operated by the user and is connected to the operation unit. By moving the operation wire forward and backward at the operation unit, a pair of forceps The member can be opened and closed.

There are several known structures of treatment sections that can be opened and closed by moving the operating wire back and forth. Patent Document 1 describes a structure in which a base end portion of a pair of forceps members and a single operation wire are connected via a pantograph-shaped link. Patent Document 2 describes a structure in which the tip of an operation wire is bent at a substantially right angle and inserted into a hole provided at a base end portion of a forceps member, and the two are joined. Patent Document 3 describes a structure in which an operation wire is fixed to an end face of a substantially columnar forceps operation wire holding pin.

Japanese Unexamined Patent Publication No. 2012-165812 JP-A-2002-06598 Japanese Unexamined Patent Publication No. 2003-093393

There is a demand for further miniaturization (smaller diameter) of the treatment tool and the endoscope into which the treatment tool is inserted from the viewpoint of further reducing the burden on the patient. Although the details will be described later, if the outer diameter of the treated portion is within the range of more than 1 mm, the structures described in Patent Documents 1 to 3 can be applied without any problem, but the above can be applied to further miniaturization. It is difficult to apply the structure.

Based on the above circumstances, it is an object of the present invention to provide a treatment tool having a structure capable of further miniaturization.

The present invention includes a long insertion portion, a treatment portion provided at the tip of the insertion portion and having a pair of forceps members that can rotate relative to each other about a rotation axis, and a base end portion of the insertion portion. The operation portion provided, the forceps member, and the operation wire connected to the operation portion and arranged in the insertion portion are provided, and the maximum dimension of the treatment portion in the radial direction is 1.0 mm or less. Each of the pair of forceps members has a shaft hole through which the rotating shaft is inserted and a pin hole provided on the proximal end side of the shaft hole, and the pin hole is a pin having an insertion hole. Is inserted, and the operation wire and the pin are joined in a state where the tip of the operation wire is inserted into the insertion hole, so that the forceps member and the operation wire are connected to each other. ..

The diameter of the operating wire may be 0.2 mm or less .

According to the treatment tool of the present invention, further miniaturization can be realized as compared with the conventional treatment tool.

It is an overall view of the treatment tool which concerns on 1st Embodiment of this invention. It is an enlarged view of the tip part of the treatment tool. FIG. 2 is a cross-sectional view taken along the line II of FIG. It is a perspective view which shows the pin to which the operation wire is connected. (A) and (b) are diagrams showing examples of welding modes of the forceps member and the operation wire, respectively. FIGS. (A) to (C) are diagrams showing examples of caulking modes of the forceps member and the operation wire, respectively. (A) and (b) are diagrams showing the connection portion between the forceps member and the operation wire in the modified example of the present invention.

The treatment tool according to the embodiment of the present invention will be described with reference to FIGS. 1 to 7. As shown in FIG. 1, the treatment tool 1 of the present embodiment is provided on the long insertion portion 10, the treatment portion 20 provided at the tip end portion of the insertion portion 10, and the proximal end side of the insertion portion 10. It includes an operation unit 40.

The insertion portion 10 is formed in a tubular shape and has flexibility. As shown in FIG. 2, the insertion portion 10 of the present embodiment is formed of a known coil sheath, but may be formed of another material. The dimensions of each part such as the length and the outer diameter of the insertion portion 10 can be appropriately set in consideration of the dimensions in the radial direction of the treatment portion 20 and the like.

FIG. 2 is an enlarged view showing a tip portion of the treatment tool 1. As shown in FIG. 2, the treatment unit 20 includes a first forceps member 21 and a second forceps member 22 connected so as to be relatively rotatable, and a pair of forceps members of the first forceps member 21 and the second forceps member 22. It includes a cover member 23 that is supported.

Each of the forceps members 21 and 22 is formed in a cup shape on the tip end side, and is configured to be able to grip and collect body tissue. Shaft holes 21a and 22a having the same diameter are formed so as to penetrate through the intermediate portions of the forceps members 21 and 22 in the longitudinal direction. The base end portions of the forceps members 21 and 22 are formed so as to penetrate the pin holes 21b and 22b used for connection with the operation wire described later.

The cover member 23 is attached to the tip end portion of the insertion portion 10, and has a rotation shaft 23a extending in a direction perpendicular to the longitudinal direction when the insertion portion 10 is linear. The rotation shaft 23a is inserted into the shaft holes 21a and 22a of each forceps member, whereby the first forceps member 21 and the second forceps member 22 are connected to the cover member 23 in a relative rotatably connected state. It is supported.

The tip ends of the operation wires 31 and 32 are connected to the base ends of the forceps members 21 and 22, respectively, via pins 25. The operation wires 31 and 32 extend through the insertion portion 10 to the operation portion 40.

As shown in FIG. 1, the operation unit 40 has an elongated operation unit main body 41 and a slider 42 attached to the operation unit main body 41. The base end portion of the insertion portion 10 is connected to the tip end portion of the operation unit main body 41. The operation wires 31 and 32 extending into the insertion portion 10 extend into the internal space of the operation portion main body 41 and are connected to the slider 42.
The slider 42 is slidably attached to the operation unit main body 41 in the longitudinal direction of the operation unit main body 41. When the user holds the operation unit main body 41 and slides the slider 42 with respect to the operation unit main body 41, the operation wires 31 and 32 move back and forth with respect to the insertion portion 10, and the first forceps member 21 and the second forceps The member 22 is pushed and pulled. However, since the first forceps member 21 and the second forceps member 22 are supported by the cover member 23 on the rotation shaft 23a, they do not advance or retreat with respect to the insertion portion 10 and rotate about the rotation shaft 23a, respectively. To do. As a result, the first forceps member 21 and the second forceps member 22 can be opened and closed by sliding the slider 42.

The basic structure of the treatment tool 1 described above is the same as that of the conventional treatment tool for endoscopy and is known. However, in the treatment tool 1, in order to enable further miniaturization, the operation wire and the forceps member are used. The connection structure has been devised, which is different from conventional endoscopic treatment tools. The details will be described below.

Miniaturization in the present invention means that the maximum radial dimension (hereinafter referred to as "diameter dimension") of the insertion portion 10 and the treatment portion 20 in a state where the pair of forceps members are closed is 1.0 mm (mm) or less. Means that. In the process of working on miniaturization, the inventor significantly changes the processing characteristics of each member from the mode when producing a treatment tool having a diameter of up to about 1.0 mm, and the structure described in each of the above-mentioned prior arts. Was found to be extremely difficult to apply.

First, in the structure described in Patent Document 1, in addition to the pair of forceps members, it is necessary to arrange a plurality of links side by side in the direction in which the rotation axis extends, but the inside of the cover member of the miniaturized treatment portion. There is no longer a space for accommodating links, pins that rotatably connect the links, and the like. If the forceps member, link, pin, cover member, etc. are thinned in order to create space, higher accuracy is required compared to the parts of a normal endoscopic treatment tool, and the cost increases significantly. In addition to being unsuitable for practical use, it is not easy to make the assembled treatment unit exhibit the desired performance.

Further, since the inner diameter of the insertion portion 10 becomes smaller as the size is reduced, it is necessary to reduce the diameter of the operation wire. Specifically, the diameter of the operation wire is about 0.1 mm to 0.2 mm. However, even if the operation wire has such a diameter, if it is bent at a substantially right angle as described in Patent Document 2, it cannot actually be accommodated inside the cover member of the miniaturized treatment portion. I understood.
Further, when the tip of the operating wire is bent and the forceps member is directly connected, a force is applied to the connecting portion when the operating wire is moved back and forth to open and close the forceps member. Here, if the diameter of the operation wire is reduced as the size is reduced, the bending rigidity of the connection portion is also reduced. As a result, a phenomenon was observed in which the shape of the connection portion changed from that at the time of manufacture due to the opening / closing operation. When the shape change occurs, the rotational resistance of the operation wire to the forceps member increases, and the force required to open and close the forceps member tends to increase.
Therefore, in miniaturization, it is extremely difficult to connect the forceps member and the operation wire by the method described in Patent Document 2.

Further, in the structure of Patent Document 3, since the outer peripheral surface of the columnar operation wire is joined to the flat end surface of the forceps operation wire holding pin, the contact area is small when the size is reduced. The difficulty has increased significantly. In addition, when the amount of heat was increased in an attempt to sufficiently join the pins, the pins were melted, and the relative rotation between the operation wire and the forceps member became poor.

With the above situation as a starting point, the inventor diligently studied and completed the structure of the present embodiment capable of solving each of the above-mentioned problems.
FIG. 4 is a perspective view of the pin 25. The pin 25 has a columnar main body 26, a large diameter portion 27 provided at one end of the main body 26 in the axial direction, and a radial direction (direction perpendicular to the axis of the main body 26) in the main body 26. ) Has an insertion hole 26a penetrating through.
The dimensions of each part of the pin 25 may be appropriately set based on the dimensions of the operation wire and the like. For example, when the diameters of the operation wires 31 and 32 are 0.1 mm, the outer diameter of the main body 26 can be 0.2 mm and the inner diameter of the insertion hole 26a can be 0.12 mm.

FIG. 3 is a cross-sectional view taken along the line II of FIG. As shown in FIG. 3, the main body 26 of the pin 25 is inserted into the pin holes 21b and 22b of the forceps members 21 and 22, respectively. The operation wires 31 and 32 are connected to the pins 25 in a state of being inserted into the insertion holes 26a of the pins 25, respectively.

In the present embodiment, the operation wires 31, 32 and the pin 25 are connected by welding using a laser beam. The laser beam is preferably emitted parallel to the axis of the pin 25, that is, the axis of the main body 26. When the laser beam is irradiated in the direction intersecting the axis of the main body 26, the main body 26 may be bent by the heat, and the relative rotation between the pin and the forceps member may be poor.

The laser beam is preferably applied to a range including a part of the pin 25 and a part of the operation wire (operation wire 31 in the figure) as shown by the circles C1 and C2 shown by the broken line in FIG. 5A. .. As shown in FIG. 5A, the irradiation points may be two places sandwiching the pin 25 in the axial direction of the operation wire, or only one of the two places. When only one is used, it is preferable to irradiate the position of the circle C1 closer to the tip of the operation wire. In this way, in addition to welding with laser light, mechanical engagement between the operation wire and the pin 25 due to the shape change of the operation wire due to laser light irradiation can be expected, so compared to the case of irradiating only the position of the circle C2. The operation wire and the pin 25 can be connected more reliably.

If the spot diameter of the laser beam used for welding is larger than the radial dimension of the operating wire, the laser beam protruding from the range of the operating wire may be applied to the forceps member and the operating wire and the forceps member may be joined. There is sex. In such a case, the end face of the main body 26 of the pin 25 may be irradiated with laser light as shown by the circle C3 shown by the broken line in FIG. 5 (b). In this case, the operation wire 31 is not directly exposed to the laser beam, but since the pin 25 is very small, a part of the end portion of the main body 26 melted by the laser beam is preferably welded to the operation wire 31. ..

As described above, according to the treatment tool 1 of the present embodiment, the pin 25 having the insertion hole 26a is inserted into the pin holes 21b and 22b provided in the pair of forceps members 21 and 22, respectively, and the insertion holes are inserted. The operation wires 31 and 32 and the forceps members 21 and 22 are connected by connecting the tips of the operation wires 31 and 32 inserted through the 26a and the pin 25.

Therefore, by appropriately adjusting the direction of the pin 25 inserted into the pin hole around the axis, the tips of the operation wires 31 and 32 protruding from the insertion portion 10 can be easily entered into the insertion hole 26a. There is no need to bend the operating wires 31 and 32 to change the direction of the tips, and there is no need to worry about the space for accommodating the bent tips even when the size is reduced.

Further, in the present embodiment, since the pin 25 is not arranged in the insertion portion 10, it is not necessary to give the pin 25 flexibility. Therefore, by changing the material and processing conditions of the pin 25, the flexural rigidity of the main body 26 that functions as the relative rotation axis between the operation wire and the forceps member can be made higher than that of the operation wires 31 and 32. By ensuring sufficient bending rigidity of the main body 26, the main body 26 is suppressed from bending during the opening / closing operation, and the state of rotating with a small resistance with respect to the pin holes 21b and 22b is preferably maintained. As a result, the amount of opening and closing force of the treatment portion can be suppressed to be small, and the opening and closing can be smoothly performed.

Further, since it is not necessary to arrange a link between the forceps member and the operation wire, the number of member points is relatively small at the connection portion between the operation wire and the forceps member, although each member is minute, and the connection portion is simple. It can be a structure. As a result, even in the case of miniaturization, a sufficient space for arranging the necessary members can be secured in the cover member 23. This eliminates the need to make the cover member and the forceps member excessively thin in the miniaturized treatment section, and as a result, it works advantageously to realize a gripping force suitable for clinical use even in the small treatment section. ..
Further, since the number of member points is small, there is little interference between the members in the treatment portion, so that it is easy to take a large opening angle of the forceps member. Therefore, it is easier to make the treatment unit exhibit the desired performance.

In the present embodiment, an example in which the operation wire and the pin are joined by laser welding has been described, but the joining mode between the operation wire and the pin is not limited to this.

For example, the operating wire and the pin may be joined by caulking. FIG. 6 shows an example of a mode in which the operation wire and the pin are connected by caulking.
As shown by an arrow in FIG. 6A, the operation wire 31 and the pin 25 may be connected by applying pressure to two points of the main body 26 to deform the main body 26.
Further, as shown by an arrow in FIG. 6B, the operation wire 31 and the pin 25 are connected by deforming the operation wire 31 by crimping two places of the operation wire 31 which is in a positional relationship sandwiching the pin 25. You may.

Further, as shown by an arrow in FIG. 6 (c), the operation wire 31 and the pin 25 may be connected by applying pressure to the four points of the main body 26 to deform the main body 26.
When the main body 26 is crimped, the pressure-applied portion projects into the insertion hole 26a and bites into the inserted operation wire 31. When pressure is applied in the direction indicated by the arrow in FIG. 6 (c), the two points on the side closer to the shaft hole 21a protrude toward the proximal end side in the insertion hole 26a, and the two points on the side far from the shaft hole 21a are inserted. It projects toward the tip side in the hole 26a. As a result, even if the operation wire 31 tries to move relative to the pin 25 in any axial direction, a part of the protruding portion tends to bite deeper into the operation wire 31. As a result, the operation wire 31 and the pin 25 can be more firmly connected.

Although one embodiment of the present invention has been described above, the technical scope of the present invention is not limited to each of the above embodiments, and various modifications can be made without departing from the spirit of the present invention. is there.

For example, the diameter of the tip of the operating wire may be different from other parts.
FIG. 7A shows an example in which the diameter of the tip portion 31a of the operation wire 31 is smaller than that of other portions. By making the diameter of the portion other than the tip portion 31a larger than the inner diameter of the insertion hole 26a, the operation wire 31 is configured so that only the tip portion 31a can pass through the insertion hole 26a. This facilitates positioning when connecting the pin and the operation wire. Further, by keeping the diameter of the other portion large without being limited by the size of the insertion hole 26a, it is possible to improve the force transmission of the operation wire and suppress buckling.
FIG. 7B is an example in which the diameter of the tip portion 31b of the operation wire 31 is larger than that of other portions. By making the diameter of the tip portion 31b larger than the inner diameter of the insertion hole 26a, the operation wire 31 is configured so that only the tip portion 31b cannot pass through the insertion hole 26a. As a result, it is possible to preferably prevent the operation wire from coming off the pin and the pin from falling off from the treatment portion.

By miniaturizing the treatment tool of the present invention, the treatment tool is not limited to the conventional treatment tool for an endoscope used by inserting it through the treatment tool channel of an endoscope, but is used in a new mode. Is possible.
For example, the treatment tool of the present invention can be inserted into the lumen of a catheter or the like inserted through the treatment tool channel, and the treatment portion can be projected from the tip of the catheter or the like. This makes it possible to guide the treatment tool of the present invention into a narrow cavity into which an endoscope cannot be inserted, for example, under fluoroscopy.
In addition, the treatment tool of the present invention can be expected to be applied to various procedures and situations that have been difficult to apply with conventional endoscopic treatment tools due to the size.

1 Treatment tool 10 Insertion part 20 Treatment part 21 First forceps member 22 Second forceps member 21a, 22a Shaft hole 21b, 22b Pin hole 23a Rotating shaft 25 Pin 26a Insertion hole 31, 32 Operation wire 40 Operation part

Claims (2)

With a long insertion part,
A treatment portion provided at the tip of the insertion portion and having a pair of forceps members that can rotate relative to the rotation axis, and a treatment portion.
An operation unit provided at the base end of the insertion unit and
An operation wire connected to the forceps member and the operation portion and arranged in the insertion portion,
With
The maximum dimension of the treatment portion in the radial direction is 1.0 mm or less.
Each of the pair of forceps members
A shaft hole through which the rotating shaft is inserted and
It has a pin hole provided on the base end side of the shaft hole.
A pin having an insertion hole is inserted into the pin hole.
The forceps member and the operation wire are connected by joining the operation wire and the pin in a state where the tip end portion of the operation wire is inserted into the insertion hole.
Treatment tool. The treatment tool according to claim 1, wherein the diameter of the operation wire is 0.2 mm or less.

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