JPS6390330A - Working method for eyeless needle - Google Patents

Abstract

PURPOSE:To perform the hole making of an eyeless needle with high accuracy by sticking the substance having closer heat conductivity to that of a needle material around the needle material in a large diameter and after executing a hole making by a beam heating at a root end part finishing the outer periphery in the necessary diameter. CONSTITUTION:A stainless steel made needle stock 1a in about 0.23mm outer diameter is solidified by burying with a solder on the plate stock where numerous holes in about 0.28mm bore diameter are made. The hole 3 having about 0.13mm inner diameter and about 0.8mm effective depth is pierced by a laser beam at the root end part of this needle stock 1a. Thereafter, the needle stock 1a is finished in the necessary eyeless needle by pulling it out of the plate stock.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a method of manufacturing a surgical suture needle, and particularly a method of manufacturing an eyeless needle having a hole at the proximal end into which a suture thread can be inserted and caulked. It is related to.

<Prior Art> Conventionally, hole processing methods for surgical eyeless suture needles generally include drilling, electrical discharge machining, and beam thermal processing using a laser or electron beam.

However, with the above-mentioned drilling or electric discharge machining method, it is difficult to make a drill or electrode with an extremely small diameter, so it is necessary to drill a highly accurate hole in a needle material of 0.3 μ or less. This was extremely difficult.

Therefore, when drilling holes in small-diameter needle materials, beam thermal processing methods using laser beams, electron beams, etc., which do not require tools, have been practiced.

However, this beam thermal processing method also has various drawbacks, and in order to improve these drawbacks, the applicant has already published Japanese Patent Application Laid-open Nos. 52-111294 and 60-170590.
Publication No. 60-184485, Publication No. 1984-3
Techniques such as those shown in Japanese Unexamined Patent Publication No. 7918 and Japanese Utility Model Application Publication No. 55-43691 have been developed and put into practical use.

<Problems to be Solved by the Invention> However, despite the development of various improved techniques as described above regarding the beam thermal processing method, the fundamental problems still remain unsolved.

Particularly in hole drilling methods where the hole diameter is large relative to the needle diameter, that is, when drilling holes with small wall thickness, the hole may bend or fall out.

Alternatively, there was a problem in that defective products such as holes and tears were frequently produced.

On the other hand, it has been known for some time that when a hole is formed in a plate material as shown in FIG. 7(a) using the beam thermal processing method as described above, a very good hole can be made. However, in spite of this, when a hole is formed at the base end of the needle material, the hole is often bent, missed, or torn as shown in FIG. 7(b). As a result of conducting various experiments to investigate the cause of this, we found that when drilling a hole with a large inner diameter compared to the needle diameter, the hole should be machined at a position that is even slightly biased to one side of the base end of the needle material. When the needle material is applied, since the wall thickness at the base end of the needle material is small overall, the temperature of the uneven part of the needle material rises rapidly, which causes the needle material on the uneven side to melt, and this part It was thought that the wall would disappear and the hole would become bent, holed, or torn.

In other words, when drilling a hole in beam thermal processing, one pulse during processing is 0.
．． Although it is a short time of less than 0.001 seconds, the temperature of the processing part is 10.
,000℃ or more, the temperature of the wall through which the heat is transferred becomes extremely high.Furthermore, the thermal conductivity of air (0.0O022cal) is higher than that of stainless steel (0.033cal/cm, s, ℃). /cm, s, °C)
is less than 1/100, and specific gravity x specific heat is also less than 1/100, so the heat escaping to the outside is almost inconceivably small.Therefore, if the wall thickness is beyond the limit,
This is thought to be because the wall melts and is no longer able to maintain its shape.

In recent years, there have been more and more cases in which microscopic parts such as brain surgeries are sutured using microscopic needles, and needles with relatively large diameter holes in microscopic needle material are increasingly being used. For example, a needle material with a diameter of 0.231 m has a diameter of 0.23 m.
A large amount of needles and the like having a hole of 13 mm in diameter (wall thickness: 0.050) have become necessary.

The present invention is a completely new technology developed in view of these drawbacks of the conventional technology.In particular, it is possible to inexpensively mass-produce small-diameter needles with relatively large-diameter holes while reducing the number of defective products. The aim is to provide a completely new technology that makes it possible.

<Means for Solving the Problems> The present invention, which solves the above-mentioned problems, uses a material having a thermal conductivity similar to that of the needle material around the needle material which is thicker than the desired needle diameter or the needle material having the desired needle diameter. A hole is formed on the base end of the enlarged needle material by integrally attaching it by laser or electron beam heat processing, and then the part that is thicker than the needle diameter is removed to produce an eyeless needle. This is a method for manufacturing eyeless needles.

Function> As described above, the present invention involves drilling a hole at the proximal end of a cough needle having a diameter larger than the desired diameter by beam thermal processing, and then cutting the outer circumferential surface of the cough needle with the hole drilled therein afterward. Since the needle is machined into a needle with the desired diameter by cutting it from There is no fear that the temperature will rise rapidly compared to the conventional method, and it is possible to prevent the occurrence of defective products such as bent holes, missing holes, or torn holes. Furthermore, the outer peripheral surface of the needle material is fixed as described above (without removing it in the later process, solder of tin and lead alloy is integrally applied around the base end of the needle material, which has been formed in advance to the diameter of the finished product). Even if this part is covered and made to have a large diameter, and a hole is drilled at the proximal end of the cough needle by beam thermal processing, problems such as bending, omission, or tearing of the hole will occur in the same way as in the method described above. It is possible to prevent the occurrence of defective products.

<Example> To specifically explain an example of the method for processing an eyeless needle according to the present invention with reference to figures, in FIGS. 1 and 2, a stainless steel needle material 1 having an outer diameter of 0.26 mm is shown. The inner diameter of the base end 2 is 0.0 by laser beam or electron beam thermal processing.
Drill hole 3 with an effective depth of 0.8mm. Next, the needle material 1 with the hole 3 drilled therein is immersed in an etching solution of 95°C to 105°C consisting of aqua regia, surfactant, and water for about 4 minutes, and the outer peripheral surface of the needle material 1 is gradually etched and polished. Then, an eyeless needle 1a having an outer diameter of 0.23I as shown in FIG. 2 is prepared! ! I crushed it.

A comparison was made between the case of directly drilling a hole with an inner diameter of 0.13 mm in a needle with a diameter of 0.231 m, as in the conventional method, and the case of implementing the above-mentioned method. In this case, the ratio of non-defective products to processed products was 45%, whereas when this method was implemented, the ratio of non-defective products to processed products was 79%.

The inventor then conducted a second example and obtained the following results.

First, a hole 66 having a hole diameter of 0.2211 is bored in the base end 5 of a needle material 4 having a diameter of 0.45n+ as shown in FIG. The diameter of the needle material 4 was ground to 0.335 mm by centerless processing, and in order to remove the grindstone grains 7 formed on the outer circumferential surface by centerless processing, barrel polishing was performed using ceramic balls and steel balls. By removing the grindstone grain 7, it was possible to obtain a needle 4a having a mirror-finished surface and a diameter of 0.3311 as shown in FIG. The yield rate when this method was implemented was 93%.

In the methods shown in the first and second embodiments, if the outer diameter machining allowance after hole drilling is small, the yield rate does not increase much, but if the outer diameter machining allowance is large, the post-processing process takes time and is costly. There is a problem with getting high. The inventor carried out another third embodiment in which the needle material with a large diameter as described above was not used, and was able to obtain the following results.

As shown in FIG. 6, a needle material 8 with a diameter of 0.23 mm is inserted into a hole of a syringe needle pipe 9 with a hole diameter of 0.28 m and an outer diameter of 0.5 as, and both are heated. After solidifying the solder 10, which has a thermal conductivity similar to that of the needle material 8, into the gap between the two and completely adhering them to each other, a hole with a diameter of 0.13 m5 is made at the base end of the needle material 8 using a laser beam. 11 was drilled, and then the solder 10 was melted while heating both, and the needle material 8 was pulled out from the hole of the pipe 9, thereby making it possible to obtain the desired eyeless needle.

The yield rate when this method was implemented was 92%. However, this method has a problem that the workability is slightly inferior to that of the first and second embodiments. Therefore, in order to perform this method more efficiently, as a fourth example, a needle material with a diameter of 0.230 mm was embedded and solidified together with solder into a plate material with many holes of 0.28 m diameter, and the base end of the needle material was solidified. 0 by laser beam
．． After drilling a 130-diameter hole, an experiment was conducted in which the needle material was removed and a desired eyeless needle was machined. By this method, good results were obtained in terms of efficiency, with a non-defective product rate of 92% or more.

Furthermore, as a fifth embodiment, 0°23N, which was previously impossible.
As a result of drilling a hole with a diameter of 0.17 mm in the needle material of the same diameter using the method of the fourth example, the yield rate was 46%, but it was possible to perform the hole.

<Effects of the Invention> Since the processing method according to the present invention has the above-described structure and operation, when this method is implemented, holes are made at the base end of the needle material by beam thermal processing. Even if the hole is slightly biased in one direction with respect to the outer diameter of the needle, the entire base end of the needle is configured to have a diameter larger than the needle diameter, so the heat is dispersed throughout. There is no risk that the temperature will rise more rapidly on one side than on the other side, thus preventing large bends, cracks, or large tears caused by the hole bending in one direction during machining, as in the past. It has features such as being able to machine needle holes in thin walls, which was previously impossible.

In addition, in the examples, it has been explained that the needle material is thicker than the desired needle diameter, or that a material having a thermal conductivity close to that of the needle material is integrally attached around the needle material, as if applied to the entire needle. It is also possible to apply the opening only to the base end.

The material to be attached to the needle material is not limited to stainless steel or solder (it may also be other metals, as long as it has a thermal conductivity relative to air that is close to that of the needle material).

[Brief explanation of the drawing]

1 and 2 are explanatory diagrams for implementing the method of the present invention, FIGS. 3 to 6 are explanatory diagrams of the other side, respectively, and FIG. 7 is an explanatory diagram of the prior art. 1.4.8 is the needle material, la, 4a is the eyeless needle, 2.5 is the base end, 3, 6.11 is the hole, 7 is the grindstone grain, 9 is the pipe,
10 is solder.

Claims (1)

[Claims] A laser or electron beam is applied to the proximal end of a needle material that is thicker than the desired needle diameter or that has been made thicker by integrally attaching a substance with thermal conductivity similar to that of the needle material around the needle material that has the desired needle diameter. A method for manufacturing an eyeless needle, characterized in that the eyeless needle is manufactured by drilling a hole by beam thermal processing such as the above, and then removing a portion that is thicker than the needle diameter.