JPH0211239A - Method for forming hole for eyeless sutural needle - Google Patents

Abstract

PURPOSE:To obtain an accurate, finished hole by making a prepared hole having a diameter equal to or smaller than a hole diameter finished by laser beam machining or electron beam machining and then making an additional work to this prepared hole. CONSTITUTION:The prepared hole 2 is made by laser beam machining or electron beam machining at the root of a needle stock 1. This prepared hole 2 is composed of a sharpened or dulled depth part 2a which has a slightly trumpet-like inlet part and a wavy and flat central part 2c. The root of this needle stock 1 is heated by a burner 3 as far as the neighborhood of the melting point and a drill which is rotated by a motor 4 and has a specified diameter or a boring tool 5 such as tungsten wire is pushed into the prepared hole 2 of the needle stock 1 to form a finished hole. In this way, the prepared hole and the finished hole are formed easily and surely on the root of the needle stock to obtain an accurate, finished hole.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a hole forming method for forming a thread attachment hole at the proximal end of an eyeless suture needle.

<Conventional technology> Conventional methods for forming this type of hole include (1) a cutting method in which the hole is cut with a drill, (2) a welding method in which a pipe is welded, and (3) a method in which the hole is formed by electrical discharge with an electrode in a liquid. electric discharge machining method,
(4) Special thermal processing methods have been implemented that utilize the instantaneous high energy of laser or electron beams to locally sublimate materials.

<Problems to be Solved by the Invention> However, the various methods described above each have the following drawbacks or problems.

(1) Drill cutting Okawa method is difficult to cut when the needle material is stainless steel, especially for holes of 0.3φ or less, the depth is about 4 to 5 times the hole diameter. This is impractical because the cost is extremely high in relation to the price of the drill and the lifespan of the drill.

(2) The method of welding pipes is very difficult to weld thin pipes and solid materials, and it has the disadvantage that it is impossible to prevent defects from getting in especially when the pipe wall thickness becomes thin. Processes such as cutting to determine the depth are complicated and costly.

(3) Electrical discharge machining has a slow machining speed, the hole is tapered to the size of the entrance, and if it is less than 0.4, the first liquid will not pass through, making it almost impossible. However, since the hole is a blind hole, if the hole diameter of the pipe is made large enough for the machining liquid to pass through, the hole (core) will not be machined and will remain, so it can also be used as a needle. It becomes impossible.

(4) Laser, electron beam, etc. processing is a processing method that instantaneously heats the material to high heat with a laser beam or electron beam and sublimates the material, so the hole shape is unstable, the accuracy is poor, and the inside of the hole is It has fatal drawbacks such as the smooth wall surface and poor thread retention after caulking.

The method according to the present invention is a completely new technology developed in view of these conventional drawbacks. In particular, this method performs additional machining on a prepared hole drilled by laser processing or electron beam processing to form a finished hole. This relates to a technique that attempts to solve the problems caused by the above-mentioned laser or electron beam processing.

Means for Solving the Problem> The present invention involves drilling a pilot hole with a diameter equal to or smaller than the finished hole diameter by laser machining or electron beam machining, and then performing additional machining on the pilot hole. This is a hole forming method for an eyeless suture needle, which is characterized by forming a finished hole.

Furthermore, the present invention is also a method of forming a hole with the pilot hole left as it is deep inside the hole configured as described above.

Function> As described above, the hole forming method according to the present invention involves drilling a pilot hole at the base end of the needle material by laser processing or electron beam processing, and then additionally machining this pilot hole to form a finished hole. First, it is possible to drill a large number of pilot holes extremely efficiently and inexpensively, and then to add pilot holes that are drilled with relatively poor precision and unstable hole shapes by laser processing or electron beam processing. It is possible to easily and reliably correct the hole by machining and form a finished hole with correct accuracy and shape.

Furthermore, when the hole forming method according to the present invention is carried out, the smooth surface formed on the inner wall surface of the technical college is transformed into an uneven surface by additional processing, thereby significantly increasing the adhesion strength of the suture thread attached to the hole after caulking. I can force it.

Furthermore, by leaving a thin pilot hole in the deep part of the hole where the suture thread is not inserted, cracks can be prevented from occurring when the inserted suture thread is swaged, and the swage process can be facilitated.

<Example> To specifically explain an example of the hole forming method according to the present invention with reference to the drawings, in FIGS. Pilot hole 2
to be drilled. As is clear from FIGS. 1(A) and 1(B), the inner part 2a of this pilot hole 2 has a sharp or bell shape, the entrance part 2b has a slight trumpet shape, and the central part 2C It is formed as a relatively smooth surface with undulations.

Next, the base end of the needle material 1 is heated by a burner 3 to near the melting point of the needle material 1, and a drilling tool 5 of a predetermined diameter rotated by a motor 4 is pushed into the prepared hole 2 of the needle material 1.
As shown in FIGS. 3(A) and 3(B), the additional machining of this prepared hole 2 is stopped when it reaches a predetermined length from the entrance part 2b to the central part 2c, or the additional machining is continued over the entire prepared hole from the entrance part 2b to the inner part 2a. The finishing hole 6 can be formed by additional machining. Especially the first
The entrance part 2b and central part 2C of the prepared hole 2 as shown in FIG. 3(A) are cut by laser machining or electron beam machining by cutting the hole to a predetermined diameter as shown by the chain line in the figure using the drilling tool 5. It is possible to form a finished surface 66 that is a mixture of surfaces formed by the process and surfaces formed by additional machining using tools.

As the above-mentioned drilling tool 5, a drill, a tungsten wire, or the like can be used. When a drill is used as the drilling tool 5, additional machining can be performed directly around the pilot hole 2 formed by laser machining or electron beam machining without heating, as described above. Further, when the pilot hole 2 is cut with a drill, spiral-shaped unevenness can be formed on the inner wall surface of the hole, thereby improving the thread stopping effect after crimping.

Further, when a tungsten wire or the like is used as the hole punching tool 5, minute irregularities are formed on the inner wall surface with which the tool 5 comes into rotational contact, thereby significantly increasing the thread stopping effect after caulking. Further, the additional machining can be performed using methods other than the above-mentioned embodiments, such as electric discharge machining.

Furthermore, when carrying out the present invention, if the narrow inner part 2a of the pilot hole is left as is at the inner part of the finished hole 66 as shown in Fig. 3(A), when this is caulked, it will become as shown in Fig. 1llIJ4. Since the suture thread 7 inserted into the finished hole 6 is gradually caulked from this narrow inner part 2a, no cranking occurs around the finished hole 6.

Furthermore, as shown in FIG. 4, the suture thread 7 is crimped by the finished hole 6 having an additionally machined uneven surface, so the thread stays in place well and there is no need to worry about it falling off.

<Effects of the Invention> Since the hole forming method according to the present invention has the above-described structure and operation, it is possible to easily and reliably form a prepared hole and a finished hole at the proximal end of a needle material for an eyeless suture needle. , and the shape or smooth surface of the pilot hole formed by laser machining or electron beam machining can be corrected by additional machining to create a highly accurate finished hole with the correct shape and uneven surface. The suture needle can be mass-produced at an extremely low cost, and if the thin inner part of the 17 holes is left as is at the inner part of the finished hole, the crimping process can be made smoother. It has characteristics such as being able to prevent the occurrence of cracks.

[Brief explanation of the drawing]

Figures 1 (A) and (B) are cross-sectional explanatory views showing the method of forming holes by implementing the method of the present invention, Figure 2 is a side view showing the state in the middle of processing, and Figure 3 (A). CB) is a cross-sectional view showing the finished hole, and FIG. 4 is a cross-sectional view with the suture thread crimped. 1 is the needle material, 2 is the pilot hole, 2a is the back part, 2b is the entrance part, 2C
3 is a burner, 4 is a motor 5 is a tool, 6 is a finished hole, and 7 is a suture thread. (B)C

Claims (2)

[Claims] (1) After drilling a pilot hole with a diameter equal to or smaller than the finished hole diameter by laser processing or electron beam processing, additional machining is performed on the pilot hole to form the finished hole. Characteristic eyeless suture needle hole formation method. (2) Hole formation for the eyeless suture needle according to claim (1), characterized in that the additional machining of the pilot hole is performed from the entrance side to the central portion, leaving the inner part of the pilot hole as it is at the back of the finished hole. Law.