JPH0274231A - Curved pipe for endoscope - Google Patents

Abstract

PURPOSE:To obtain a curved pipe stable in welding strength by bringing the outer peripheral surface of a wire receiver into contact with the groove or hole of a nodal ring to fix the same by the irradiation with laser beam. CONSTITUTION:A grooves 5 or holes are provided to the fixing part of the wire receiver 4 of the node ring 1 of a curved pipe. The wire receiver 4 and nodal ring 1 positioned on the inner surface of the nodal ring 1 are irradiated with laser beam from the outer periphery of the nodal ring 1 through the grooves 5 or holes while said beam is moved in the longitudinal direction of the wire receiver 4. Or, the nodal ring 1 and the wire receiver 4 are irradiated with laser beam while said beam is moved in the aforementioned longitudinal direction and integrally welded to form a curved pipe.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a curved tube installed in a curved portion of a flexible endoscope, and particularly to a node ring constituting the curved tube.

[Conventional technology]

Conventionally, when fixing a wire receiver through which a wire for operating the distal end of an endoscope is inserted, to each node ring of a curved tube installed in the curved part of an endoscope, it is necessary to The end of the joint between the inner surface and the outer peripheral surface of the cylindrical wire receiver was irradiated with a laser beam, and the ends of the joint were welded to form a single body.

(Refer to Japanese Unexamined Patent Publication No. 102607/1983).

In addition, in order to improve the welding strength between the two, by forming a recess on the inner surface of the joint ring, or by forming a part of the outer shape of the wire receiver to have the same curvature as the joint ring, the contact area, that is, the welding range (length) ) is described in the above publication.

[Problem to be solved by the invention]

However, the conventional curved pipe and its manufacturing method have the following problems.

When welding the wire receiver and the node ring by irradiating each longitudinal end of the wire receiver with a laser beam, either turn both members toward the laser light irradiation direction or move the laser irradiation device. necessary, and the equipment for this is complex and expensive. Further, the configuration becomes complicated when the laser beam is guided by a guide member (for example, a fiber bundle or a mirror). This problem also occurs when the contact area between the wire receiver and the node ring is increased as described above. Since the welded area of the obtained curved pipe is small, sufficient strength cannot be obtained. For this reason, when a concave portion is formed on the inner surface of the nodal ring, the outer surface protrudes, causing the problem that the circumscribed circle of the curved tube becomes larger and the diameter of the curved portion becomes larger. In addition, if the contact area is made too large while matching the external curvature of the wire receiver to the curvature of the node ring, the inner cross-sectional area of the curved pipe will decrease, making it difficult to insert and assemble built-in items such as fiber bundles, or easily breakage. There were problems such as this, and there was a limit to increasing the contact area, and there were also restrictions to increasing the welding strength.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a curved tube for an endoscope, which can be easily welded by laser beam irradiation and can improve the welding strength of the wire receiver.

(Means and effects for solving the problems) The present invention provides a groove or a hole in the wire receiving fixing portion of the node ring constituting the curved pipe, and connects the node ring from the outer peripheral side of the node ring through the cough groove or hole. irradiating the wire receiver and the node ring located on the inner surface of the wire receiver with a laser beam while moving the wire receiver in the longitudinal direction of the wire receiver, and/or
Alternatively, it is a curved tube in which the node ring and the wire receiver are integrally welded by irradiating a laser beam while moving in the longitudinal direction.

〔Example〕

Hereinafter, the present invention will be explained in detail based on examples.

(First Embodiment) FIG. 1a is a perspective view of a node ring showing a first embodiment of the present invention, FIG. 1 is an enlarged perspective view of a wire receiver of the first embodiment, and FIG. FIG. 3 is a perspective view of the curved pipe in which the receiver is fixed to the node ring, and FIG. 3 is an explanatory diagram of the jig and tool used for fixing.

In the figure, at each end of the circular tube-shaped node ring 1, connecting parts 2.3 for connecting with other node rings are formed to protrude in pairs, shifted by 180 degrees. has been done. Each wire receiver 4 on the inner peripheral surface of the node ring 1
The outer peripheral surface of the node ring 1 has a length shorter than the length of the wire receiver 4, corresponding to the fixed positions (four locations in the figure). A rectangular groove 5 is formed. This groove 5 may be formed by cutting out with a laser beam or by press punching.
Further, the shape may be approximately oval.

The wire receiver 4 has a contact surface 4a that has a part of its outer peripheral surface approximately matching the inner diameter dimension (curvature) of the joint ring l, and the other part of the circumferential surface, that is, the center side of the joint ring l, has a cylindrical surface 4b. It has become.

The contact surface 4 between each groove 5 of the node ring 1 and the wire receiver 4 as described above
For example, the jig 6 shown in FIG. It has four recessed portions 8 for storage, and a cylindrical portion 9 that fits into the inner circumferential surface of the node ring l.

Therefore, the wire receiver 41 and the joint ring 1 are inserted into the jig 6 in this order. Thereafter, the jig is placed at a laser beam irradiation position of a laser irradiation device (not shown), and the jig is moved in the axial direction relative to the laser beam, or the laser beam is applied to the jig in the axial direction of the jig and tool. while moving to
A laser beam is irradiated to the contact area between the wall surface 5a of the groove 5 of the node ring l (one wall surface parallel to the axial direction of the node ring l) and the contact surface 4a of the wire receiver 4, and the two are welded and integrated. .

Next, the jig 6 is rotated to weld the contact portion between the other wall surface 5b and the contact surface 4a of the wire receiver 4. Thereafter, the jig 6 is further rotated to irradiate a laser beam to the contact portion between the wall surface 5a and wall surface 5b of each groove 5 and the contact surface 4a, thereby welding the joint ring 1 and each wire receiver 4. A curved pipe 20 is obtained (Fig. 2).

Generally, the spot diameter of the laser beam is about 0.4a, so if the width of the groove 5 is about 0.8a, both wall surfaces 5a and 5b can be irradiated and welded at the same time. The groove 5 is 1<
Since it has a rectangular shape with the relationship L, the wall surface on the short side of the groove 5 can also be welded and integrated.

Note that the external shape of the wire receiver 4 is not limited to the above, and a cylindrical shape may also be welded. In this case, groove 5 of node ring 1
The contact portion between one wall surface 5a and the outer circumferential surface 4a of the wire receiver 4 may be welded, or the width of the groove 5 may be narrowed and a line of laser light may be irradiated.

Depending on the case, a short metal wire, metal powder, or a paste containing metal powder is placed or applied in the groove 5 and welded to fill the gap between the inner circumferential surface of the node ring l and the outer circumferential surface of the wire receiver 4, The curved pipe 20 may be formed by integrating them.

(Second Embodiment) A perspective view and a sectional view of a main part of a curved pipe in which a wire receiver is fixed to a node ring, as shown in FIGS. 4a and 4b, according to a second embodiment of the present invention,
The explanation will be based on a perspective view of the jig and the tool shown in FIGS. In the following embodiments, parts that are different from the first embodiment will be explained, and parts similar to those in the first embodiment will be denoted by the same reference numerals and detailed explanation thereof will be omitted.

In the figure, a rectangular groove 5 bored in the axial direction on the outer peripheral surface of the node ring l has wall surfaces 5a and 5b having a length of 2, which is longer than the length of the cylindrical wire receiver 10. In addition, the width of the groove 5 is set such that the outer circumferential surface 10a of the wire receiver 10 does not protrude from the outer circumferential surface of the node ring 1 when the wire receiver 10 is abutted from the inside of the node ring 1, as shown in FIG. It is set as follows.

By fitting the wire receiver 10 into the groove 5 as described above, the outer circumferential surface 10a of the wire receiver IO comes into contact with both wall surfaces 5a and 5b of the groove 5, so that the two walls are welded and integrated at the contact portions. A curved pipe 20 is obtained.

In order to align and weld the node ring l and the wire receiver IO of the second embodiment, it is preferable to use a hollow jig, an example of which is shown in FIGS. 5a and 5b, for example.

A cross-shaped groove 11 is formed at the end of the jig 6. The slotted grooves 11 and the hollow portions 12 provide elasticity to the ends.

Further, a tapered surface I3 is formed on the outer circumferential surface of the end portion as an insertion end of the nodal ring l, and then a pressing surface 14 having a diameter larger than the inner diameter of the nodal ring l. A cylindrical portion 9 that fits into the inner diameter of the 15° nodal ring 1 with a tapered surface for discharge. There are four recesses 8 extending from the end to accommodate the wire receiver 10, and a recess 7 that engages with the connecting portion 2 of the joint ring l to position the joint ring l (in order to improve workability, 4 locations) are provided at each location.

Therefore, when the joint ring l is inserted from the end of the jig 6, the end part is reduced in diameter and guides the joint ring l, and the recessed part 8
It reaches a predetermined position by enclosing the wire receiver IO placed inside. At this time, since the end returns to its original diameter, the wire receiver IO is made to protrude into the middle of the node l. In addition, when inserting the node ring l, seal the wire receiver lO with adhesive to the recessed part 8.
It is easier to work if the jig and tool 6 are temporarily fixed and the tool 6 is placed upright.

Reference numeral 16 denotes a pressing rod for forcibly restoring the end of the jig 6, and when the end cannot perform sufficient elastic action, it can be inserted to expand the diameter, or retreated to easily reduce the diameter. It is used when

In this way, the laser beam or the jig is moved in the axial direction with the outer peripheral surface 10a of the wire receiver IO in contact with both wall surfaces 5a and 5b of the joint ring l assembled in the jig and tool 6. The contact parts are welded, then one part is rotated and the other part is irradiated with laser light, and this operation is repeated. After the four wire receivers 10 are welded to the joint ring 1, the press rod 16 is removed if used, the wire receiver 10 is pulled out along the tapered surface 15, and the work is completed.

In the second embodiment as well, a sufficient welding length can be secured in the same way as described above, and the amount of protrusion of the wire receiver 10 inward from the node ring 1 is reduced, so that it can be used for observation inserted into a curved tube of an endoscope. The cross-sectional area through which built-in objects such as optical fiber bundles for lighting, air tubes, and water tubes are inserted becomes larger, so damage to the built-in objects can be prevented, or the outer diameter of the curved tube can be made smaller by the reduction in the insertion area. It is possible to achieve the desired effect.

Note that the shape of the groove 5 of the node ring 1 may be a substantially oval shape having a substantially straight wall surface that contacts the outer circumferential surface 10a of the wire receiver 10 in two rows.

(Third example) A third embodiment of the present invention is shown in a perspective view of a node ring in FIG.

Wire receiver 4 (or wire receiver 10) in node ring 1
A plurality of holes 16 are bored in each fixed portion in the axial direction of the nodal ring l, and a bridge 17 remains between the holes 16. Each of the holes 16 can be formed by laser beam irradiation.

In order to fix the wire receiver 4 to the node ring 1 as described above, the two can be welded and integrated by using the jig 6 shown in FIG. 3 and the same operation as in the first embodiment.

In the third embodiment, the bridges 17 remaining between the holes 16 are melted by the laser beam and flow into the space (contact area or gap) between the inner peripheral surface of the node ring 1 and the wire receiver 4. The effect is that the welding area is expanded and the welding strength is improved.

In each of the above embodiments, the wire receivers 4°10 are fixed at four locations on the inner circumferential surface of the joint ring l, but the wire receivers 4°10 are not limited to this, and may be fixed at unequal locations or at two locations. , depending on the wire receiver fixed to one node ring.

(Effect of the invention) The outer circumferential surface of the wire receiver is brought into contact or almost in contact with the groove or hole formed in the nodal ring, and the laser beam is applied to this part by relative movement and/or laser beam from the outer circumferential side of the nodal ring. Since the spot diameter is increased and both are fixed, the welding area is large (and a curved pipe with stable welding strength can be obtained. Welding work can be easily performed by simply rotating around the axis, and the configuration of the laser beam irradiation device is also simple.

[Brief explanation of the drawing]

1A and 1B are perspective views of a node ring and a wire receiver according to the first embodiment of the present invention, FIG. 2 is a perspective view of a curved pipe in which a wire receiver is fixed to the node ring, and FIG. An explanatory view of the main parts showing an example of the jig used in the example, FIGS. 4a and 4b are a perspective view and a sectional view of the main parts of the curved pipe in which the wire receiver of the second embodiment is fixed to the node ring, and FIG. a and b are perspective views of essential parts and an explanatory view of the state of use showing an example of a jig used in the second embodiment, and FIG. 6 is a perspective view of a joint ring of the third embodiment. 1... Node ring 4. IO... wire receiver 5.
...Groove 6...Jig 1G...Hole 20...Curved pipe Fig. 3

Claims (1)

[Scope of Claims] In a curved tube in which a wire receiver is fixed to the inner surface of a joint ring installed in a curved part of an endoscope, a groove or a hole is provided in the wire receiver fixed part of the joint ring, and the groove is provided with a groove or a hole. Alternatively, a curved tube for an endoscope, characterized in that the wire receiver and the node ring are integrally welded through a hole.