JPS61131724A - Production of exterior unit of endoscope - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing an endoscope exterior unit that allows exterior parts to be joined with excellent sterilization resistance, appearance, etc.

[Prior Art] When an endoscope is generally used in the medical field and is inserted into a body cavity, mucus and dirt in the body cavity tend to adhere to the endoscope.

For this reason, cleaning is required, and in particular, it is essential that the exterior parts of the endoscope withstand sterilization by steam sterilization. Furthermore, since it is necessary to inject water into the body cavity through an endoscope, each joint in the exterior part is required to have sufficient sealing performance. Furthermore, it must have the appearance quality required for a medical device. The main exterior units forming this exterior part include a main body block-shaped unit to which a water injection device section, a detachable device section, etc. are attached, and a tubular unit inserted into a body cavity.

Conventionally, the parts constituting these units are made by cutting or forming copper-zinc alloy for the block-shaped unit and copper-nickel alloy or copper-nickel-zinc alloy for the tubular unit into the required shape, and then Both units are joined by brazing using a brazing agent such as nickel-based hard solder, tin-lead soft solder, or tin-antimony solder. The exterior unit roughly joined by the above method is coated with two-layer nickel-chromium plating or three-layer copper-nickel-chromium plating, and the sterilization process prevents corrosion of the exterior unit and its joints. It was endowed with sterilization resistance.

However, when a plated item is sterilized, the plated layer may peel off.

However, in recent years, manufacturers have been trying to avoid the above plating process.
The use of corrosion-resistant alloy steel for the exterior unit is progressing. However, all manufacturers use the conventional method of joining the exterior units using brazing. In this case, in order to avoid corrosion from the joint, efforts were made to improve the brazing work so that no brazing agent remained on the outside surface of the joint.

[Problems to be solved by the invention] In the conventional technology, for example, in tin-lead soft wax and tin-antimony wax, the brazing agent itself has poor contact resistance, so even a small amount of the waxing agent is applied to the outer surface. If it remains, corrosion will progress from this area during the sterilization process. or,
Regarding nickel-based hard solder, the brazing agent itself has considerable corrosion resistance under sterilization conditions, but the melting point of the waxing agent is 650~
Because the temperature is as high as 850°C, even if the parts are joined using the vacuum brazing method, there will be a significant thermal effect near the joints of the units to be joined.
This results in loss of strength, appearance, and sterilization resistance.

Furthermore, since brazing work requires flux application as a pre-process and deburring and cleaning processes as a post-process,
It requires a large amount of man-hours, and the results largely depend on the skill of the worker, and it is also difficult to automate.

The brazing work described above is extremely difficult to join for the exterior unit of the endoscope, which is made of a corrosion-resistant alloy, and is a work that requires skill, and the results are not satisfactory. It was impossible. The present invention has been made in view of these problems, and it is an object of the present invention to provide a method for manufacturing an endoscope exterior unit that is low-cost and enables bonding with good sterilization resistance.

[Means for Solving the Problems] As shown in FIG. 1, this device includes a block-shaped member 32 and a tubular member 33, which serve as exterior parts of an endoscope, fitted together, and an edge 38 of this fitted part. a laser oscillation unit 34 with an irradiation energy of 20 watts to 100 watts;
The exterior is arranged so as to be irradiated with laser light 41, and has a welded part formed under irradiation conditions such that the irradiation angle between the irradiation axis of the laser light 41 and the central axis of the tubular member 33 is in the range of 5 degrees to 60 degrees. unit is provided.

[Function] The method for manufacturing the exterior unit of the endoscope is to use the block-shaped member 32.
and the tubular member 33, and the fitted edge 38
The laser beam 41 having an irradiation energy of 20 watts to 100 watts emitted from the laser oscillation unit 34 is irradiated with an umbrella, and the angle between the irradiation axis of the laser beam 41 and the central axis of the tubular member 33 is 5 degrees to 60 degrees. By irradiating a range of irradiation angles, the irradiated area is melted and welded.

Examples] The present invention will be specifically described below with reference to the drawings.

Figures 1 to 5 relate to the manufacturing method of the present invention, with Figure 1 showing the principle of welding by a laser beam, and Figure 2 showing the principle of welding by a laser beam.
3 and 3 show an optical viewing tube to which the manufacturing method of the present invention is applied and a sheath with a mandoline attached, FIG. 4 shows an enlarged view of the vicinity of the connection part in FIG. 3, and FIG. indicates a portion joined by the manufacturing method of the present invention.

An optical viewing tube (telescope) 1 having an exterior unit to which the manufacturing method of the present invention can be applied has an elongated insertion section 2 and a fitting portion of the rear end of this insertion section 2, as shown in FIG. It consists of a large-diameter eyepiece part 3 that is connected by welding or the like, and an optical image of an object such as an affected area in front of the objective optical system is displayed on the distal end side of the insertion part 2, such as an affected area (not shown in the figure). It is configured such that it can be observed at the eyepiece section 3 on the hand side via an image transmission means inserted therein.

Furthermore, as shown in the third factor, the sheath 4 to which the manufacturing method of the present invention is applied includes a hollow tubular sheath insertion section 5 and a fitting section 6 into which the rear end of the sheath insertion section 5 is fitted (see Fig. 4). A connecting part 9 is provided at the rear end of the sheath main body 7, and a mandolin (rod-shaped device) 10 or an optical device shown in FIG. The viewing tube 1 is attached and the insertion section 2 thereof can be inserted into the sheath insertion section 5.

In the water injection device section 8, a water supply cock 11 is interposed on the outer periphery of the sheath main body section 7, and two water supply pipes 12, 12 (only one is shown in the figure) are provided vertically or horizontally symmetrically. Liquid can be injected from the end of the water pipe 12.12 into the body cavity through the sheath insertion section 5. Furthermore, water can be drained by connecting one of the water pipes 12 to a drainage device via a tube.

On the other hand, the mandolin 10 is provided with an obturator 14 at the distal end of the shaft section 13 that can be inserted into the sheath inserting section 5 to close the opening 5a at the distal end of the sheath inserting section 5. As shown in FIG. 4, the rear end side of the mandolin 10 has a large diameter step and is connected to a mandolin main body 15, which is fitted into the inner circumferential surface of the sheath main body 7. A tapered outer peripheral surface is formed. On the rear end side of this mandolin body part 15, when attached to the sheath body part 7,
A knob portion 16 that protrudes rearward is provided.

By the way, the connecting part 9 provided in the sheath 4 to which the mandolin 10 or the optical viewing tube 1 can be attached is a ring-shaped fitting part made by concentrically cutting out the outer periphery of the enlarged rear end of the sheath body part 7. A recess 18 is formed in which a connecting ring is rotatably fitted.

Therefore, grooves 21 for accommodating the bottles 20 protruding from both sides of the main body 15 of the mandolin 10 are provided in the wall surface of the recess 18 along the axial direction of the sheath insertion section 5 (direction for attaching and detaching). By rotating the ring 19, for example, the inner circumferential portion of one of the connecting rings engages the rear side of the groove 21 in which the bottle 20 is stored, and by restricting the movement of the bottle 20, each groove 21 The mandolin 1o can be fixed by restraining each bottle 20 inside. Incidentally, by rotating in the opposite direction, the restraint is released and the mandolin 10 can be removed.

Further, on the outer periphery of the connection ring 19, there is a detachable operation lever 2.
2 is provided protrudingly, and the base side of this lever 22 is slidably accommodated in a circumferential groove 23 having an appropriate length in the circumferential direction on the outer circumferential surface of the recess 18, and within the range of rotation within this circumferential groove 23. , attachment and detachment are now functional.

A groove 25 is provided at the rear end of the connecting portion 9 to accommodate a positioning bin 24 protruding from the mandoline 10 or the like. or,
The front end of the connecting ring 19 has an O-ring 2 fitted in the recess 18.
It is in contact with 6.

In the manufacturing method of the present invention, for example, the sheath insertion part 5 and the fitting part 6 of the sheath body part 7 shown in FIG. 4 are joined by laser beam welding, and FIG. 1 shows the laser beam welding. This is a diagram showing the principle, and in the same figure, the outer diameter is approximately equivalent to the sheath body 7, the outer diameter is 18 mm, the inner diameter is 10 mm,
A block-shaped test piece (member) 32 with a length of 3Qmm is approximately equivalent to the sheath insertion part 5, and has an outer diameter of iQmi1 and an inner diameter of 9.
．． A tubular test piece (member) 33 having a length of 1501 is provided.

The block-shaped test piece 32 is fitted onto a tubular test piece 33, and this fitted block-shaped test piece 32 is chucked into a test piece fixing jig (not shown) that can rotate and adjust the vertical inclination angle. There is.

The block-shaped test piece 32 and the tubular test piece 3'3 fitted therein are rotated at an appropriate speed by the test piece fixing jig.

On the other hand, the laser beam 41 emitted from the laser oscillation unit 34 passes through a slit 35 disposed in front of the laser oscillation unit 34, and becomes a parallel beam at a collimator lens 36 disposed in front of the slit 35. A reflective mirror 37 is disposed in front of the collimator lens 36, and the laser beam 41 is directed toward the edge 38 of the fitting portion of the tubular test piece 33 and the block-shaped test piece 32, which are being rotated by the reflective mirror 37. The laser beam 41 changed in this direction passes through three condensing lenses disposed below the reflecting mirror 37 and is condensed onto the edge 38 of the fitting portion. Note that the reflecting mirror 37, the condensing lens 39, and the edge 38 of the fitting portion are arranged so as to be located on the same straight line. As shown in FIGS. 5(a) and 5(b), the block-shaped test piece 32 and the tubular test piece 3
3, a welded portion 42 is formed by laser beam welding.

Furthermore, the block-shaped test piece 32 chucked in the fixing jig and the tubular test piece 33 fitted therein can be fixed to the test piece 3 by adjusting the vertical inclination angle of the fixing jig.
The irradiation angle between the axis of 2.33 and the irradiated laser beam 41 can be freely changed.

On the other hand, a gas outlet 40 is connected to a gas pipe from a gas cylinder (not shown).
Acetylene gas is ejected toward the edge 38 of the mating portion to prevent oxidation of the weld and its vicinity.

Next, the laser beam 41 emitted from the laser emitting unit 34 is converted into a parallel beam by a collimator lens 36, and the direction is changed by a reflection mirror 37 to a tubular test piece 33 and a block-shaped test piece 32, respectively, made of corrosion-resistant alloy steel. When the edge 38 of the fitting portion is irradiated, the irradiated portion is instantly melted and welded.

However, if the irradiation energy is too low, a welded part with good sealing properties will not be formed, and if it is too high, a wide area will be heated, which will significantly impair the appearance and reduce the corrosion resistance of the welded part. Furthermore, if the irradiation angle is too small, the laser beam 41 will not be able to melt the surface of the tubular test piece 33 and the sealing performance will be impaired; if it is too large, the surface of the block-shaped test piece 32 will not be melted. In addition to impairing the sealing performance, the tubular test piece 33 may dissolve too much and form a hole. Therefore, the following experiment was conducted to confirm the optimal range for these points.

First, a first experiment was conducted in which the irradiation angle was kept constant and the irradiation energy of the laser beam was gradually increased. The material used for the test piece was austenitic stainless steel 5US304, which is a corrosion-resistant alloy steel, and the welding experiments were conducted at an irradiation angle of 45 degrees and an irradiation energy in the range of 10 W to 12 degrees OW, increasing successively in 5 W increments. Each sample was evaluated for sealing performance, appearance, and steam sterilization resistance.

In addition, regarding the evaluation of sealing property, the joint welded part 42 of the sample
The presence or absence of air bubbles is determined by placing the tube in a water tank and sending 5 kQ/cm2 of air into the tube.External evaluation is performed by observing the welded area under a microscope, and steam sterilization resistance is evaluated using a steam sterilization method. The sample was held in water vapor at 135° C. and 2.2 atm for 5 minutes and judged based on the presence or absence of discoloration.

The first result is the relationship between irradiation energy and weld zone characteristics.
The result is as shown in the table.

Table 1 The results show that at an irradiation angle of 45 degrees, a welded part with good sealing performance, appearance, and steam sterilization resistance can be obtained if the irradiation energy is in the range of 20 W to 100 W.

Next, we conducted further experiments regarding the irradiation angle.

The conditions were to fix the irradiation energy to 50W and set the irradiation angle to 2.
．． Welding experiments were conducted in the range from 5 degrees to 87.5 degrees, increasing in 2.5 degree increments, and for each sample, the sealing performance and appearance of the tubular test piece were evaluated, and the irradiation angle and weld area characteristics were evaluated. The results of the relationship are shown in Table 2.

Table 2 The results show that when the irradiation energy is 50 W and the irradiation angle is in the range of 5 degrees to 60 degrees, good sealing performance is obtained and a welded part without thermal deformation can be obtained.

Further, based on the experimental results shown in Tables 1 and 2 above, various irradiation angles and watts of irradiation energy were varied. First, the conditions are that the irradiation angle of the laser beam is 5 degrees and 60 degrees.
Welding experiments were carried out by fixing the irradiation energy at 10W to 120W and increasing the irradiation energy in steps of 5W in the range from 10W to 120W. As a result, at any irradiation angle, if the irradiation energy was in the range of 20 W to 100 W, similar to the results in Table 1, welded parts with good sealing performance, appearance, and steam sterilization resistance could be obtained. Next, welding experiments were carried out by fixing the laser beam irradiation energy to 20W and 100W and increasing the irradiation angle in steps of 2.5 degrees from 2.5 degrees to 87.5 degrees. Similarly to the results shown in Table 2, it was revealed that a welded part with good sealing performance and no thermal deformation could be obtained if the irradiation angle was in the range of 5 degrees to 60 degrees. From the above experimental results, the sealing performance, appearance, and
Disinfectivity was confirmed.

Although 5uS304 is used in the present invention, other corrosion-resistant alloy steels may be used, and although only the resectoscope has been described, it goes without saying that the present invention can also be applied to the exterior parts of other rigid endoscopes.

[Effects of the Invention] As described above, according to the manufacturing method of the present invention, the irradiation energy of the laser beam is applied to the edges of the external fitting portions of both members in a range of 20 W to 100 W, and the irradiation energy is aligned with the axis of both members. The irradiation angle of the irradiated laser light is 5 degrees to 6 degrees.
By joining both parts in the 0 degree range, the sealing performance is as excellent as that of conventional brazing, and the appearance is also improved without the need for deburring, which is necessary in soft brazing work. It satisfies the requirements for medical equipment, and also shows no discoloration during sterilization-resistant treatment, providing a good disinfection method.

[Brief explanation of the drawing]

This relates to the manufacturing method of the present invention shown in FIGS. 1 to 5,
FIG. 1 is a principle explanatory diagram showing how welding is performed by the manufacturing method of the present invention, FIG. 2 is an explanatory diagram showing an optical viewing tube to which the manufacturing method of the present invention is applied, and FIG. FIG. 4 is a partially cutaway side view of the sheath to which the manufacturing method is applied, FIG. 4 is an enlarged cross-sectional view of the vicinity of the connection part of the sheath in FIG. 3, and FIG. 5 is a test piece welded by the manufacturing method of the present invention. FIG. 5(a) is a longitudinal cross-sectional view, and FIG. 2(b) is an enlarged front view. 1... Optical viewing tube, 2... Insertion section, 3... Eyepiece section,
4... Sheath, 5... Sheath insertion part, 7... Sheath body part, 32... Block-shaped test piece (member)
, 33... Tubular test piece (member), 34... Laser oscillation unit, 38... Edge of fitting part, 41...
...Laser light, 42...Welding part Figure 1 Figure 4 Welding arm procedure amendment document February 11, 1985

Claims (2)

[Claims] (1) In a method for manufacturing an exterior unit that forms the exterior part of an endoscope, a block-shaped member and a tubular member each made of corrosion-resistant alloy steel are fitted together, and the exposed edge of the fitted part of the joined part is Irradiation energy is 20 watts or 10
A method for manufacturing an endoscope exterior unit, characterized in that a welded portion is formed by irradiating a laser beam under irradiation conditions of 0 watts and an irradiation angle of 5 to 60 degrees. (2) The method for manufacturing an endoscope exterior unit according to claim 1, wherein the irradiation angle indicates the angle formed by the axes of the block-like member and the tubular member and the irradiated laser beam.