JP4725787B2 - Endoscope connection structure - Google Patents

Description

  The present invention relates to a connecting structure for an endoscope member.

Flexible structural members such as metal stranded wires and coil pipes are widely used for structural members such as endoscope forceps and other endoscope treatment tools and various structural members of the endoscope itself. Laser welding that is used and does not require the use of a troublesome burner or a flux that needs to be cleaned afterwards as means for connecting and fixing the end of such a flexible shaft to the member to be connected Has been adopted (for example, Patent Documents 1 and 2).
Japanese Patent Publication No. 6-16790 Japanese Patent Publication No. 7-28854

  When connecting and fixing the flexible shaft to the connected member by laser welding or the like, care should be taken not to laser weld the exposed portion of the flexible shaft that extends from the connected member side. Must be attached. If there is a weld in the exposed part of the flexible shaft, not only will the length of the hard part increase, but the part that becomes brittle due to heat during welding will be bent directly by external force. This is because the portion may be easily damaged during use.

  Therefore, in the inventions described in Patent Documents 1 and 2, laser light is irradiated to the outer surface of the middle part of the tubular connected member into which the flexible shaft is inserted, and the connected member and its member The inner flexible shaft is welded. However, in order to melt the flexible shaft-like body inside the connected member with the laser beam irradiated from the outer surface of the connected member as described above, a remarkably high output laser device is required and at the same time the outer surface of the connected member In order to perform laser welding, it is necessary that the members to be welded are in close contact with each other. Therefore, there are many cases where laser welding is performed incompletely and appropriate connection strength cannot be obtained.

  The present invention has been made to solve such a problem, and the flexible shaft-like body is appropriately and firmly fixed to the connected member without being excessively irradiated with the laser, and is flexible. It is an object of the present invention to provide a connecting structure for an endoscope member that can be connected and fixed by laser welding at a position deeper than the exposed portion of the sex shaft.

  The connection structure for an endoscope member according to the present invention is the connection structure for an endoscope member in which the end portion of the metal flexible shaft is connected and fixed to the metal connection member by welding. An end portion of the flexible shaft-like body is inserted into a receiving hole formed in the connecting member, and a metal annular auxiliary ring for welding fitted into the flexible shaft-like body and a receiving hole of the connected member The abutting portion with the edge portion is welded by laser light irradiation from the side, whereby the welding auxiliary ring, the connected member, and the end of the flexible shaft-like body are integrally welded. The end of the flexible shaft is connected and fixed to the connected member.

The end of the flexible shaft is formed with a retaining portion having a larger outer diameter, and the retaining portion is inserted into a receiving hole formed in the connected member, so that the auxiliary ring for welding May be formed with an inner diameter through which the retaining portion cannot pass.
In addition, the endoscope member connecting structure according to the present invention is an endoscope member connecting structure in which an end portion of a metal flexible shaft is connected and fixed to a metal connected member by welding. An annular retaining portion having a large outer diameter is formed only at the end of the flexible shaft, and the retaining portion is inserted into a receiving hole formed in the connected member, so that the retaining portion cannot pass. The contact portion between the metal welding auxiliary ring formed on the flexible shaft-like body and the edge of the receiving hole of the connected member is welded by laser light irradiation from the side. Thus, the welding auxiliary ring and the connected member may be integrally welded so that the end of the flexible shaft-like body is connected and fixed to the connected member.

  The retaining portion is formed by fixing the retaining member to the end of the flexible shaft, and the contact portion between the welding auxiliary ring and the edge of the receiving hole of the connected member is lateral. At the same time as welding is performed by laser beam irradiation, the retaining member located inside is also welded. The retaining member is formed in a cylindrical shape and extends from the receiving hole of the connected member to the auxiliary ring for welding. The laser beam irradiated from the side to the contact portion between the auxiliary ring for welding and the edge of the receiving hole of the connected member The flexible shaft-like body may not be reached by hitting the retaining member.

  Further, the retaining portion may be formed by heat-molding the end portion of the flexible shaft body, and may be formed in a spherical shape. The end portion of the auxiliary ring for welding is formed in the receiving hole of the connected member. A small-diameter protruding portion to be inserted is formed so that the laser beam irradiated from the side hits the abutting portion between the auxiliary ring for welding and the edge of the receiving hole of the connected member so that the small-diameter protruding portion is flexible. The shaft-like body may not be reached.

  In addition, the flexible shaft may be a stranded wire, the flexible shaft may be a coil pipe, and when the flexible shaft is a coil pipe, it is prevented from coming off. The portion may be formed with a larger winding diameter near the end of the coil pipe. Further, if the member to be connected is deformed inward by the heat of laser welding near the contact portion of the welding auxiliary ring and is in close contact with the outer periphery of the flexible shaft, the connection strength increases.

  According to the connecting structure of the endoscope member of the present invention, the contact portion between the welding auxiliary ring and the edge of the receiving hole of the connected member is welded by laser light irradiation from the side, so that welding is performed. Since the flexible shaft-like body passed through the auxiliary ring and the connected member are connected and fixed, the flexible shaft-like body is appropriately attached to the connected member without requiring excessive laser irradiation. In addition, it can be firmly fixed at a position deeper than the exposed portion of the flexible shaft.

Embodiments of the present invention will be specifically described below with reference to the drawings.
FIG. 1 shows a distal end portion of an endoscopic biopsy forceps employing the present invention. However, the present invention can be widely applied to various endoscopic treatment tools other than biopsy forceps and portions where end portions such as metal wires or coils used in the main body of the endoscope are connected and fixed by welding. Can do.
In FIG. 1, reference numeral 1 denotes a stainless steel wire tightly wound coil pipe that is passed through a treatment instrument guide tube of an endoscope (not shown), and a stainless steel tip connected to the tip of the coil pipe. A link mechanism 4 is disposed in a slit portion 3 formed in the main body 2. A support shaft 5 is attached to the vicinity of the distal end of the distal end main body 2 so as to cross the slit portion 3, and a pair of forceps cups 6 are rotatably supported by the support shaft 5, and the link mechanism 4 on the rear end side. It is connected with.

  In the coil pipe 1, a flexible operation wire 7 made of a stranded wire obtained by twisting a large number of thin stainless steel wires is loosely passed, and a connecting rod disposed at the rear end of the link mechanism 4 8, the distal end of the operation wire 7 is connected and fixed. Therefore, by pushing and pulling the operation wire 7 from the hand side, the link mechanism 4 operates and the forceps cup 6 is driven to open and close.

  A is a connecting and fixing portion between the operation wire 7 and the connecting rod 8, B is a connecting and fixing portion between the coil pipe 1 and the tip body 2, and the operation wire 7 is flexible in the connecting and fixing portion A. The connecting rod 8 is a connected member. In the connecting and fixing portion B, the coil pipe 1 is a flexible shaft and the tip body 2 is a connected member. In both of the connection fixing portions A and B, the metal short cylindrical auxiliary rings 11 and 12 are added, and the flexible shafts 7 and 1 and the connected members 8 and 2 are laser-welded. It is connected and fixed by.

FIG. 2 shows an enlarged view of the connecting and fixing portion A between the operation wire 7 and the connecting rod 8, and the end of the operation wire 7 itself is heated and melted by plasma discharge or laser irradiation to restore the original wire. A retaining part 9 solidified in a spherical shape having a diameter larger than the diameter is formed, and the retaining part 9 is inserted into a receiving hole 10 that is formed in a recess in the end surface of the connecting rod 8 formed in a columnar shape.
The welding auxiliary ring 11 is made of, for example, stainless steel, and has an inner diameter that is fitted to the operation wire 7 so that the retaining portion 9 cannot be pulled out, and an outer diameter that is outside the connecting rod 8. It is formed in a size that does not differ greatly from the diameter. And the front end surface of the welding auxiliary ring 11 is in contact with the edge of the receiving hole 10 on the end surface of the connecting rod 8 over the entire circumference, and the laser beam L is irradiated from the side to the entire circumference. The welding auxiliary ring 11 and the connecting rod 8 are connected and fixed by laser welding at their contact surfaces. Y is the laser weld.

  Further, the operation wire 7 also passes through the slight uneven portion of the contact surface between the welding auxiliary ring 11 and the connecting rod 8 and reaches the operation wire 7 from the side, so that the operation wire 7 is also connected to the welding auxiliary ring 11 and Laser welding is integrally performed together with the connecting rod 8. In this embodiment, the vicinity of the base portion of the retaining portion 9 formed in a spherical shape at the tip of the operation wire 7 is welded to the auxiliary ring 11 for welding and the connecting rod 8. Yes.

  In the connecting structure of the endoscope member thus configured, the metals are melted and integrated by laser welding over the entire circumference at the contact portion between the welding auxiliary ring 11 and the connecting rod 8. Since the connection and fixing of both members by welding are securely and securely performed, the operation wire 7 is also welded together therewith, and the retaining portion 9 cannot pass through the welding auxiliary ring 11. Are connected to each other very firmly. Further, since the vicinity of the exposed portion X where the operation wire 7 is exposed outwardly from the other end side of the auxiliary welding ring 11 is not welded, bending stress is applied to that portion of the operation wire 7. However, the phenomenon that the operation wire 7 is easily broken does not occur. Laser welding may be performed continuously over the entire circumference, but may be performed discontinuously, for example, at a plurality of locations at equal intervals in the circumferential direction. About this point, it is the same also about the laser welding part Y of each part demonstrated below.

FIG. 3 is an enlarged view of the connecting and fixing portion B between the coil pipe 1 and the tip body 2, and a retaining portion 13 having a winding diameter larger than the original coil diameter is provided at several turns at the tip portion of the coil pipe 1. The retaining portion 13 is formed and fitted into the receiving hole 14 formed in a cylindrical shape at the rear end portion of the distal end main body 2 so as to hit the back.
The auxiliary welding ring 12 is made of, for example, a stainless steel pipe, and has an inner diameter that is large enough to fit the coil pipe 1 so that the retaining portion 13 cannot be pulled out. It is formed in the size without a big difference. The front end surface of the welding auxiliary ring 12 is in contact with the edge of the receiving hole 14 on the end surface of the front end main body 2 over the entire circumference, and the laser light L is irradiated from the side to the entire periphery. The welding auxiliary ring 12 and the tip main body 2 are connected and fixed by laser welding at their contact surfaces. Y is the laser weld.

  The coil pipe 1 also passes through the slight uneven portion of the contact surface between the welding auxiliary ring 12 and the tip body 2 and reaches the coil pipe 1 from the side, so that the coil pipe 1 also has the welding auxiliary ring 12 and Laser welding is integrally carried out together with the tip body 2. In this embodiment, the vicinity of the base portion of the retaining portion 13 formed by increasing the winding diameter at the tip of the coil pipe 1 is the auxiliary ring 12 for welding and the tip body 2. And are welded. When the rear end portion of the tip main body 2 is heated and melted by the laser light L irradiation and deformed inward, and is brought into close contact with the outer surface of the coil pipe 1, the coil pipe 1 is laser-welded very firmly.

  In the connecting structure of the endoscope member thus configured, the metals are melted and integrated by laser welding over the entire circumference at the contact portion between the welding auxiliary ring 12 and the tip body 2. The connection and fixing of the two members by welding are performed securely and firmly, and the coil pipe 1 is also welded together therewith, and the retaining portion 13 cannot pass through the welding auxiliary ring 12. Are connected to each other very firmly. Further, since the coil pipe 1 is not welded in the vicinity of the exposed portion X where the coil pipe 1 is exposed outwardly from the other end side of the welding auxiliary ring 12, bending stress is applied to that portion of the coil pipe 1. However, the phenomenon that the coil pipe 1 is easily broken does not occur.

  FIG. 4 shows a second embodiment of the present invention. In the connection fixing portion A between the operation wire 7 and the connection rod 8, the portion near the tip of the auxiliary welding ring 11 is in the receiving hole 10 of the connection rod 8. The small-diameter protrusion 16 inserted into the protrusion is formed so as to project, and the laser beam L irradiated from the side on the contact portion between the welding auxiliary ring 11 and the edge of the receiving hole 10 of the connecting rod 8 strikes the small-diameter protrusion 16. This prevents the operation wire 7 from being reached. Such a configuration is effective when, for example, the operation wire 7 is very thin and the laser beam L hits it, causing thermal degradation that becomes a practical problem.

  FIG. 5 shows a third embodiment of the present invention. In the connection fixing portion A between the operation wire 7 and the connection rod 8, for example, a pipe material is fitted and fixed to the end of the operation wire 7 to prevent it from coming off. 17 is configured. The material of the retaining member 17 may be made of metal such as stainless steel or plastic, and the fixing to the operation wire 7 may be any means such as welding, brazing or welding.

  In this embodiment, the contact portion between the welding auxiliary ring 11 and the edge of the receiving hole 10 of the connecting rod 8 is welded by the irradiation of the laser beam L from the side, and at the same time, is located inside. The retaining member 17 is also welded, and at the same time, the operation wire 7 is integrally welded. Other configurations are the same as those of the first embodiment, and the same operational effects as those of the first embodiment can be obtained.

  FIG. 6 shows a fourth embodiment of the present invention. The retaining member 17 of the third embodiment of FIG. 5 is extended to the inside of the auxiliary welding ring 11 from the inside of the receiving hole 10 of the connecting rod 8. By placing the operation wire 7 in a position straddling the auxiliary welding ring 11, the side of the contact portion between the auxiliary welding ring 11 and the edge of the receiving hole 10 of the connecting rod 8 is lateral. The laser beam L irradiated from the contact with the retaining member 17 is prevented from reaching the operation wire 7. Such a configuration is effective when an operation wire 7 having a small diameter is used as in the second embodiment.

  FIG. 7 shows a fifth embodiment of the present invention, in which the retaining portion 9 is omitted from the first embodiment shown in FIG. 2, and the other configuration is the same as that of the first embodiment. is there. With this configuration, the connection strength (tensile strength) of the operation wire 7 with respect to the connection rod 8 may be slightly reduced as compared with the case where the retaining portion 9 is provided, but the strength of the laser weld Y and the exposure of the operation wire 7 may be reduced. Since the strength and the like of the portion X are the same as those in the first embodiment, the cost can be reduced by adopting this configuration in a portion that does not interfere with the specification.

  FIG. 8 shows a sixth embodiment of the present invention, in which the coil pipe 1 of the first embodiment shown in FIG. Other configurations are the same as those of the first embodiment. With this configuration, the connection strength (tensile strength) of the coil pipe 1 with respect to the tip body 2 may be slightly reduced as compared with the case where the retaining portion 13 is provided. Since the strength and the like of the portion X are the same as those in the first embodiment, the cost can be reduced by adopting this configuration in a portion that does not interfere with the specification.

  In addition, the strength of laser welding is increased at the same time as the rear end portion of the tip body 2 is heated and melted by the laser light L irradiation and deformed into a state of being tightly in contact with the outer surface of the coil pipe 1. The effect of preventing slipping out occurs.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side cross-sectional view of a distal end portion of an endoscopic biopsy forceps employing an endoscope member connection structure according to a first embodiment of the present invention. Side surface sectional drawing of the connection fixing | fixed part of the operation wire and connection rod of the connection structure of the member for endoscopes of 1st Example of this invention. The side sectional view of the connection fixing part of the coil pipe of the connection structure for the endoscope member of the first embodiment of the present invention and the tip body. Side surface sectional drawing of the connection fixing | fixed part of the operation wire and connection rod of the connection structure of the member for endoscopes of 2nd Example of this invention. Side surface sectional drawing of the connection fixing | fixed part of the operation wire and connection rod of the connection structure of the member for endoscopes of the 3rd Example of this invention. Side surface sectional drawing of the connection fixing | fixed part of the operation wire and connection rod of the connection structure of the member for endoscopes of the 4th Example of this invention. Side surface sectional drawing of the connection fixing | fixed part of the operation wire and connection rod of the connection structure of the member for endoscopes of the 5th Example of this invention. Side surface sectional drawing of the connection fixing | fixed part of the coil pipe of the connection structure of the member for endoscopes of the 6th Example of this invention and a front-end | tip main body.

Explanation of symbols

1 ... Coil pipe (flexible shaft)
2. Tip body (connected member)
7 ... Operation wire (flexible shaft)
8 ... Connecting rod (member to be connected)
DESCRIPTION OF SYMBOLS 9 ... Retaining part 10 ... Receiving hole 11 ... Auxiliary ring for welding 12 ... Auxiliary ring for welding 13 ... Retaining part 14 ... Receiving hole 16 ... Small diameter protrusion part 17 ... Retaining member A ... Connection fixing part B ... Connection fixing part L ... Laser beam X ... Exposed part Y ... Laser weld

Claims (13)

In the connection structure of the endoscope member in which the end portion of the metal flexible shaft is connected and fixed to the metal connected member by welding,
An end portion of the flexible shaft-like body is inserted into a receiving hole formed in the connected member, and a metal annular welding auxiliary ring fitted on the flexible shaft-like body and the covered body. The contact portion of the connecting member with the edge of the receiving hole is welded by laser light irradiation from the side, whereby the auxiliary ring for welding, the connected member, and the end of the flexible shaft-like body A connecting structure for an endoscope member, wherein the end of the flexible shaft-like body is connected and fixed to the connected member by being integrally welded.   2. The connecting structure for an endoscope member according to claim 1, wherein an end portion of the flexible shaft-like body is formed with a retaining portion having a larger outer diameter, and the connected member has The connecting structure for an endoscope member, wherein the retaining portion is inserted into the formed receiving hole, and the auxiliary welding ring is formed to have an inner diameter through which the retaining portion cannot pass. In the connection structure of the endoscope member in which the end portion of the metal flexible shaft is connected and fixed to the metal connected member by welding,
A retaining portion having a large outer diameter is formed at the end of the flexible shaft-like body, and the retaining portion is inserted into a receiving hole formed in the connected member. A laser beam from the side of the contact portion between the metal welding auxiliary ring formed in an annular shape that cannot pass and fitted on the flexible shaft and the edge of the receiving hole of the connected member It is welded by irradiation, whereby the welding auxiliary ring and the connected member are integrally welded so that the end of the flexible shaft-like body is connected and fixed to the connected member. The connection structure of the member for endoscopes characterized by these.   4. The connection structure for an endoscope member according to claim 2, wherein the retaining portion is formed by fixing the retaining member to an end portion of the flexible shaft-like body. Member connection structure.   5. The connecting structure for an endoscope member according to claim 4, wherein a contact portion between the auxiliary ring for welding and an edge portion of the receiving hole of the connected member is welded by laser light irradiation from a side. At the same time, the connecting structure for the endoscope member is welded to the retaining member located inside.   The connecting structure for an endoscope member according to claim 5, wherein the retaining member is formed in a cylindrical shape and extends from the receiving hole of the connected member into the auxiliary ring for welding. Laser light that is disposed in a state of being fitted to the flexible shaft-like body and is irradiated from the side to a contact portion between the auxiliary ring for welding and an edge portion of the receiving hole of the connected member The connection structure of the member for endoscopes which does not reach to the flexible shaft-like body by hitting the retaining member.   The connecting structure for an endoscope member according to claim 2 or 3, wherein the retaining portion is formed by thermoforming the end portion of the flexible shaft body itself. Connected structure.   The connection structure for an endoscope member according to claim 7, wherein the retaining portion is formed in a spherical shape.   In the connecting structure for an endoscope member according to claim 7 or 8, a small-diameter protruding portion to be inserted into the receiving hole of the connected member is formed to protrude at one end portion of the auxiliary ring for welding, The laser beam irradiated from the side to the contact portion between the welding auxiliary ring and the edge of the receiving hole of the connected member does not reach the flexible shaft-like body by hitting the small-diameter protruding portion. The connection structure of the member for endoscopes which becomes.   The connection structure for an endoscope member according to any one of claims 1 to 9, wherein the flexible shaft-like body is a stranded wire.   The connection structure for an endoscope member according to any one of claims 1 to 6, wherein the flexible shaft-like body is a coil pipe.   The endoscope member connection structure according to claim 2 or 3, wherein the flexible shaft-like body is a coil pipe, and the retaining portion increases a winding diameter in the vicinity of the end of the coil pipe. The connection structure of the member for endoscopes formed in this way.   12. The connecting structure for an endoscope member according to claim 1, wherein the member to be connected is deformed inward by heat of laser welding in the vicinity of a contact portion with the auxiliary welding ring. The connection structure of the member for endoscopes closely_contact | adhered to the outer periphery of the said flexible shaft-shaped body.

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