JP3875834B2 - Endoscope treatment tool manufacturing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an endoscope treatment tool and a method for manufacturing the same, in which a tip actuating member is operated by a wire that can move forward and backward in a coil.
[0002]
[Prior art]
In recent years, endoscopes are used not only for diagnosis but also for various treatments. In the treatment using such an endoscope, a treatment tool for an endoscope that is inserted through a treatment tool insertion channel of the endoscope is used. Most endoscope treatment tools are composed of a wire and a distal end working member formed at one end of the wire, and the wire is advanced and retracted with the distal end working member protruding from the distal end of the endoscope. The tip actuating member can be operated to perform various treatments.
[0003]
For example, in an endoscopic biopsy forceps which is a kind of such an endoscopic treatment tool, the first forceps cup and the second forceps cup, which are tip operation members, can be opened and closed according to the advancement and retraction of the wire. The desired living tissue can be gripped by the first forceps cup and the second forceps cup by operating the wire from the hand.
[0004]
Conventional endoscopic biopsy forceps are shown in FIGS. FIG. 4 shows an overall image of the endoscopic biopsy forceps inserted through the treatment instrument insertion channel of the endoscope. The distal bending portion 2 formed at the distal end of the flexible tube 3 of the insertion portion of the endoscope 1 is inserted into the body, and an image captured by an objective optical system arranged at the forefront of the distal bending portion 2 is taken as an eyepiece. 6, and the distal end bending portion 2 can be freely bent by rotating an operation operation knob 5 installed on the operation portion 4.
[0005]
Further, the endoscope 1 has a treatment tool port 7, and the biopsy forceps 201 can be inserted into the treatment tool insertion channel 11 from the treatment tool port 7. Furthermore, the first forceps cup 205a and the second forceps cup 205b, which are the distal end working members of the biopsy forceps 201 inserted into the treatment instrument insertion channel, are exposed from the distal end portion of the endoscope 1. Here, the first forceps cup 205a and the second forceps cup 205b can be opened and closed by operating the operation handle 221 provided at the proximal portion of the biopsy forceps 201 in the longitudinal direction of the shaft. .
[0006]
FIG. 5 shows the periphery of the distal end working member of the biopsy forceps 201. Each of the first forceps cup 205a and the second forceps cup 205b has a flat plate-like first forceps cup arm portion 206a and a second forceps cup arm portion 206b that are integrally formed. Further, each of the first forceps cup arm portion 206a and the second forceps cup arm portion 206b has a forceps cup support shaft engaging hole 211 that engages with the forceps cup support shaft 204. Here, the first forceps cup 205a and the second forceps cup 205b are operated by rotating the first forceps cup arm 206a and the second forceps cup arm 206b with respect to the axis of the forceps cup support shaft 204. And can be opened and closed.
[0007]
Further, the first forceps cup arm portion 206a and the second forceps cup arm portion 206b are slidably sandwiched inside a slit portion 203a having a U-shaped cross section of the distal end working portion support member 203. Further, the slit portion 203 a has a forceps cup support shaft engaging hole, and the forceps cup support shaft engaging hole engages with the forceps cup support shaft 204. Accordingly, the forceps cup support shaft 204 and the forceps cup support shaft engaging hole 211 of each forceps cup arm portion are positioned at the position of the forceps cup support shaft engaging hole of the slot 203a.
[0008]
Further, each of the first forceps cup arm portion 206a and the second forceps cup arm portion 206b further has a link support shaft engaging hole 221. Here, each of the link support shaft engagement holes 221 is engaged with each of the link support shafts 214. Further, each of the link support shafts 214 is engaged with each of the link support shaft engaging holes 222 of the link plate 207, and each of the link plates 207 is a first forceps cup arm portion 206a and a second forceps cup arm portion 206b. Close to each of the slidable. Therefore, the first forceps cup arm portion 206a and the link plate 207 in close contact with the first forceps cup arm portion 206a are respectively connected to the axis of the link support shaft 214 to be engaged, and the second forceps cup arm portion 206b and the first forceps cup arm portion 206b. The link plates 207 that are in close contact with the two forceps cup arms 206b are rotatable with respect to the axis of the link support shaft 214 to be engaged.
[0009]
In addition, each of the link plates 207 further has an operation support shaft engaging hole 231. Further, the operation support shaft 234 is rotatably inserted in both the operation support shaft engagement holes 231 of the link plate 207 and the operation support shaft engagement holes drilled in the plate-like portion of the joint fitting 240. Furthermore, the tip of the operation wire 212 is connected to the joint fitting. Further, the proximal end of the operation wire 212 is connected to the operation means 221 of the biopsy forceps 201. Therefore, the operation wire 221 can be advanced and retracted by operating the operation means 221. Further, since the joint fitting 240 is slidably engaged with the through hole 203b drilled in the distal end working portion support member 203, the joint fitting 240 is advanced and retracted as the operation wire 212 advances and retracts, and the operation support shaft 234 and the forceps The distance from the cup support shaft 204 can be changed. Here, when the distance between the operation support shaft 234 and the forceps cup support shaft 204 is decreased, the distance between the link support shafts 214 is increased, and thus the first forceps cup 205a and the second forceps cup 205b are opened. On the other hand, when the distance between the operation support shaft 234 and the forceps cup support shaft 204 increases, the distance between the link support shafts 214 decreases, and the first forceps cup 205a and the second forceps cup 205b are closed. That is, by operating the operating means 221, the first forceps cup 205a and the second forceps cup 205b can be freely opened and closed.
[0010]
Here, in order to prevent the wire 212 from being broken, the wire 212 is covered with the coil 213 and elastically reinforced. Further, the tip of the coil 213 is joined to the tip working portion support member 203 with solder so that the wire 212 can smoothly advance and retreat in the coil 213.
[0011]
However, in the conventional endoscopic biopsy forceps, the solder soaks into the coil 213, the coil 213 and the wire 212 are joined, and the wire 212 may not be able to advance and retreat. Further, the hardened portion 215 made of solder becomes large, and there is a possibility that stress is concentrated on the hardened portion 215 and is easily bent. Furthermore, since the coil 213 and the distal end working unit support member 203 are joined using soldering, the base material must be washed with the flux before soldering and the flux removed after soldering.
[0012]
Therefore, in the endoscopic biopsy forceps described in JP-A-1-2402053, the distal end working unit support member and the coil are laser-welded.
[0013]
However, in the above-described endoscopic biopsy forceps, there is a possibility that the laser enters the coil through the gap between the coils, and the coil and the wire are joined as in the case of using soldering. Further, in the case of the endoscopic biopsy forceps 301 that joins the coil 313 and the distal end working support member 303 using laser welding as shown in FIG. 6, the joint near the proximal end surface 303 c of the distal end working support member 303. An edge 315 a is formed at 315. For this reason, the process of removing this edge 315a was required.
[0014]
Furthermore, there is a possibility that the laser beam is reflected and a high-energy laser is irradiated to the worker, which makes the work dangerous. Furthermore, since the laser welding apparatus is more expensive than other processing apparatuses, there is a problem that the cost is increased. Further, the laser rapidly raises the temperature of the laser irradiation region, and the temperature gradient between the laser irradiation region and the adjacent region becomes large, which may cause damage to the welding region due to thermal strain or the like.
[0015]
[Problems to be solved by the invention]
The present invention solves the above-mentioned problems, and a method for manufacturing an endoscope treatment tool that can manufacture an endoscope treatment tool that does not cause a problem at the joint between the coil and the distal end working support member with fewer steps, and An endoscope treatment tool manufactured by the manufacturing method is provided.
[0016]
[Means for Solving the Problems]
In order to achieve the above object, in the method of manufacturing an endoscope treatment tool according to claim 1, the distal end portion of the treatment tool of the coil and the distal end working support member are fusion-bonded by arc welding. That is, in the present invention, the coil and the tip actuating support member are heated by being exposed to the arc column by arc welding, so that the heated region is limited to the surface of the coil and the tip actuating support member. Therefore, unlike the endoscopic biopsy forceps described in JP-A-1-2402053, the laser does not pass through the gap between the coils, and an unexpected region is not welded.
[0017]
In addition, since the arc column is not an electromagnetic wave, the arc column is not reflected on the welding region and irradiated to the operator unlike the laser beam in laser welding.
[0018]
Furthermore, the arc welding apparatus is less expensive than the laser welding apparatus, and the cost of capital investment can be kept low.
[0019]
In addition, unlike the laser beam, the arc column transmits radiant heat to the periphery of the welded area, so the temperature gradient between the welded area and the adjacent area can be kept small. There is no risk of breakage or edges.
[0020]
In addition, in order to facilitate the fusion bonding of the coil and the tip working support member,
The tip working support member has a substantially cylindrical portion whose inner diameter is substantially equal to the outer diameter of the coil,
It is good also as a structure which melt-joins the said coil and the said front-end | tip operating support member by arc welding, after inserting the said coil in the substantially cylindrical part of the said front-end | tip operating support member (Claim 2). In this case, since the coil and the tip working support member are temporarily fixed by inserting the coil into the substantially cylindrical portion of the tip working support member, the coil and the tip working support member can be easily melt-bonded. it can.
[0021]
In addition, at least one through hole is formed in the substantially cylindrical portion of the distal end working support member in the diameter direction of the substantially cylindrical portion, and the treatment instrument distal end portion of the coil and the coil are welded by arc welding at the position of the through hole. It is good also as a structure which melt-joins a front-end | tip operation | movement support member (Claim 3). In this case, since the through hole is filled by arc welding, the surface of the tip working support member can be formed smoothly.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a cross-sectional view of the periphery of a distal end working support member of an endoscopic biopsy forceps according to an embodiment of the present invention. The structure of the biopsy forceps for endoscope in the embodiment of the present invention is the same as that of the conventional example shown in FIG.
[0023]
FIG. 2 shows a state before welding the coil and the distal end working support member in the endoscopic biopsy forceps according to the embodiment of the present invention. In the biopsy forceps 101, the cylindrical portion 103c of the distal end working support member 103 is formed with a welding hole 103d, which is a round hole, in the diameter direction of the cylindrical portion 103c. Here, the inner diameter of the cylindrical portion 103 c of the distal end working support member 103 is substantially the same as the outer diameter of the coil 113. A coil 113 is inserted into the cylindrical portion 103 c of the distal end working support member 103.
[0024]
A state in which the coil 113 and the distal end working support member 103 are welded is shown in FIG. The coil 113 is connected to the first electrode 401, and a second electrode 402 is provided in the vicinity of the welding hole 103d. The second electrode 402 has a cylindrical shape whose diameter is substantially the same as the diameter of the welding hole 103d, and is arranged so that its longitudinal direction substantially coincides with the drilling direction of the welding hole 103d. Furthermore, in order to prevent oxidation of the weld hole 103d, the periphery of the weld hole 103d and the second electrode 402 is filled with argon gas.
[0025]
Here, by supplying a predetermined power between the first electrode 401 and the second electrode 402, an arc column 403 is generated between the welding hole 103 d and the second electrode 402. Since the temperature of the arc column is as high as 5000K or higher, the peripheral portion of the weld hole 103d and the surface of the coil 113 at the position of the weld hole 103d are instantaneously melted to form the joint 115. Here, the arc column 403 connects the second electrode 402 and the peripheral portion of the weld hole 103 d that is the portion closest to the second electrode 402 among the portions electrically connected to the first electrode 401. Occurs on a straight line. Next, by stopping the supply of power between the first electrode 401 and the second electrode 402 and extinguishing the arc column 403, the joint 115 is cooled to its solidification point and hardened, as shown in FIG. The coil 113 and the tip working support member 103 are joined to each other at the position of the welding hole 103d. Here, the region directly heated by the arc column 403 is limited to the portion exposed to the arc column, that is, the peripheral portion of the welding hole 103d of the tip working support member 103 and the surface of the coil 113 at the position of the welding hole 103d. The Therefore, by setting the time during which power is supplied between the first electrode 401 and the second electrode 402 to such a length that the inside of the coil 113 is not melted by heat conduction (for example, several milliseconds). Only the tip operation support member 103 and the coil 113 can be reliably joined. Furthermore, since radiant heat is transmitted to the adjacent region adjacent to the welded region, the temperature gradient between the welded region and the adjacent region can be kept small, and damage or edges around the welded region due to thermal strain or the like do not occur.
[0026]
In the embodiment of the present invention, the weld hole 103d is a round hole, but the weld hole is not limited to the shape of the embodiment of the present invention. For example, the weld hole is elongated to increase the joint strength. It is good also as a hole shape.
[0027]
【The invention's effect】
As described above, according to the method for manufacturing an endoscope treatment tool and the endoscope treatment tool of the present invention, there are fewer endoscope treatment tools that do not cause a problem at the joint between the coil and the distal end working support member. It can be realized in the process.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a periphery of a distal end working support member of an endoscopic biopsy forceps manufactured by using a method for manufacturing an endoscope treatment tool according to an embodiment of the present invention.
FIG. 2 shows a state before welding a coil and a distal end working support member in an endoscopic biopsy forceps according to an embodiment of the present invention.
FIG. 3 shows a state in which a coil and a tip working support member are welded in an endoscopic biopsy forceps according to an embodiment of the present invention.
FIG. 4 shows a state where an endoscopic biopsy forceps according to a conventional manufacturing method is inserted into a treatment instrument insertion channel of an endoscope.
FIG. 5 is a cross-sectional view of a distal end portion of an example of an endoscopic biopsy forceps according to a conventional manufacturing method.
FIG. 6 is a cross-sectional view of the periphery of a distal end working support member of another example of an endoscopic biopsy forceps according to a conventional manufacturing method.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Endoscope 2 Tip bending part 3 Insertion part Flexible tube 4 Operation part 5 Operation knob 6 Eyepiece part 7 Treatment tool port 11 Treatment tool insertion channel 101 Endoscopic biopsy forceps 103 Tip action part support member 103c Tip action Part support member cylindrical part 103d welding hole 115 joint part 201 biopsy forceps 203 for endoscope distal end working part support member 203a slot part 203b through hole 204 forceps cup support shaft 205a first forceps cup 205b second forceps cup 206a First forceps cup arm portion 206b Second forceps cup arm portion 207 Link plate 211 Forceps cup support shaft engagement hole 212 Operation wire 213 Coil 214 Link support shaft 215 Joint portion 221 Link support shaft engagement hole 222 Link support shaft Engagement hole 231 Operation support shaft engagement hole 234 Operation support shaft 240 Joint metal fitting 301 Endoscopic biopsy forceps 303 Tip working portion support member 31 Operating wire 313 coil 314 link shaft 315 junction 315a edge 401 first electrode 402 second electrode 403 arc column

Claims (4)

A method for manufacturing an endoscope treatment tool that operates a distal end working member that is exposed from an endoscope distal end by moving a wire forward and backward from an endoscope proximal end side,
The tip actuating member is attached to a tip actuating support member that limits movement of the tip actuating member,
Covering the wire with a coil;
Exposing the treatment tool distal end portion of the coil and the distal end working support member to an arc column to heat and melt them both, and then cooling them to join them together,
A method for manufacturing an endoscopic treatment tool. The tip working support member has a substantially cylindrical portion whose inner diameter is substantially equal to the outer diameter of the coil,
After the coil is inserted into the substantially cylindrical portion of the tip working support member, the treatment tool tip of the coil and the tip working support member are exposed to an arc column to heat and melt both, and then cool this The method for manufacturing an endoscope treatment tool according to claim 1, wherein the two are joined together. At least one through-hole is drilled in a diameter direction of the substantially cylindrical portion in the substantially cylindrical portion of the tip operation support member,
The treatment tool distal end portion of the coil and the distal end working support member are exposed to an arc column at the position of the through hole, both are heated and melted, and then the two are joined by cooling them. Item 3. A method for manufacturing an endoscope treatment tool according to Item 2. Connecting a first electrode to the endoscopic treatment instrument;
The second electrode having a substantially cylindrical shape having a diameter substantially the same as the diameter of the through hole is formed such that the longitudinal direction of the second electrode substantially coincides with the drilling direction of the through hole. Bringing the electrode close to the through hole,
By supplying a predetermined electric power between the first electrode and the second electrode, an arc column is generated between the second electrode and the tip operation support member, and the peripheral portion of the through hole The method for manufacturing an endoscope treatment instrument according to claim 3, wherein a concave joint portion is formed by melting the core.

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