JPH09216021A - Method for working small hole - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately work small holes without producing a lot of chips even when their dipmeters are not larger than the thickness of a sheet. SOLUTION: Using a punch/laser combined working machine which is provided with a punching head 3 and a laser beam machining head 7 to which transmission of vibration from the punching head 3 is prevented, first, prepared holes 9 are provided on a metal plate 8 by executing thermal cutting with the laser beam machining head 7 and, next, the small holes are made by executing finish machining to the prepared holes 9 with the punching head 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small hole machining method,
More specifically, the present invention relates to a small hole processing method for forming small holes in a metal plate material.

[0002]

2. Description of the Related Art Conventionally, punching, laser processing and the like have been used to make a hole in a metal plate material. In addition, holes are also drilled.

[0003]

However, in punching, a very large force is required to punch a small hole having a diameter of not more than the plate thickness, and the punch cannot withstand strength. The problem is that it is virtually impossible to provide small eyelets. Also, in the case of thermal cutting using a laser or plasma, small holes with a fairly small diameter can be made, but the roundness of the small holes obtained is
There is a problem that the cylindricity varies and the processing accuracy is poor. Further, in the case of drilling, there is a problem that the productivity is inferior such that the number of steps is larger than that of punching and laser processing, or punching and plasma processing, and a large amount of cutting powder is generated.

The present invention has been made in order to solve such a problem, and even a small hole having a diameter equal to or less than the plate thickness can be provided with high accuracy and without generating a large amount of cutting powder. An object is to provide a small hole processing method.

[0005]

In order to achieve the above-mentioned object, the small hole drilling method according to the present invention is a small hole drilling method for making a small hole in a plate material. It is characterized in that the prepared hole is processed by heat cutting such as, and then the prepared hole is finished by punching.

In the small hole drilling method of the present invention, since the prepared hole initially provided is formed by thermal cutting, it can be made to have a considerably small diameter. Since this prepared hole is inferior in accuracy, it is finished by punching to be a small hole with excellent accuracy, but since the finish processing by this punching is a process that scrapes off only the peripheral wall surface part of the prepared hole, from the beginning Since the load on the punch is smaller than punching for punching a plate material, the punch is not damaged even when the diameter of the small hole is smaller than the plate thickness of the plate material. Further, a large amount of cutting powder is not generated unlike the drilling.

According to the small hole machining method of the present invention, the thermal cutting process and the punching process can be carried out by using the combined machine having the thermal cutting process head and the punching head. By performing processing using such a composite processing machine, it is possible to efficiently form the small holes in the plate material.

Further, in the small hole drilling method of the present invention, tapping can be performed on the small holes obtained by punching. As a result, a screw hole having a small diameter can be accurately provided.

The objects of the present invention will become apparent from the detailed description given below. However, while the detailed description and specific examples describe the most preferred embodiments, various changes and modifications within the spirit and scope of the invention will be apparent to those skilled in the art from the detailed description, and This is described as an example.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, specific embodiments of the small hole machining method according to the present invention will be described with reference to the drawings.

FIG. 1 is a partially cutaway schematic perspective view of a punch / laser combined processing machine 1 used in a small hole processing method according to an embodiment of the present invention. The punch / laser combined processing machine 1 includes a punch processing head 3 attached to a main body frame 2 and a laser processing head 7 arranged near the punch processing head 3. Here, the laser processing head 7 is provided at the tip of the laser light guide tube 6 whose base end is attached to the laser oscillator 5 supported on the ground through the air spring 4.

FIG. 2 shows how the punch / laser combined processing machine 1 is used to first perform laser processing on the plate material 8 to form the prepared hole 9. In order to perform this laser processing, a dust collecting duct 10 is provided below the laser processing head 7 as shown in a partial sectional view of FIG. The plate member 8 is arranged between the dust duct 10. In this state, the laser beam is applied from the laser processing head 7 to the plate material 8 to form a prepared hole 9 in the plate material 8,
The dross generated at this time is collected in the dust collecting duct 10.

The prepared hole 9 thus provided is shown in FIG.
As shown in (a) and (b), the cross-sectional shape is not a perfect circle, and the cylindricity of the wall surface is not good. Here, the diameter of the prepared hole 9 and the thickness of the plate material 8 appear to be approximately the same, but the diameter of the prepared hole 9 is considerably smaller than the thickness of the plate material 8 by adjusting the laser beam.
It is also easy to provide.

Next, the prepared hole 9 is finished by the punching head 3 as shown in FIG. In order to perform this finishing process, as shown in FIG. 3A which is a partial sectional view, a die 11 is installed below the punching head 3, and the punching head 3 and the die 11 are connected to each other. The plate material 8 is arranged between them. The punching head 3 is provided so that the punch 13 penetrates the central portion of the circular plate retainer 12.

In this state, the plate retainer 12 is pressed against the plate member 8 and the punch 13 is projected from the plate retainer 12, whereby the peripheral wall surface portion 14 of the prepared hole 9 is shown in FIG. 3 (a). It is scraped off by the punch 13 as described above. In other words, the punching head 3 performs the shaving process on the prepared hole 9, and as a result, the small hole 15 is formed in the plate member 8.

As shown in FIG. 3A and FIG. 3B which is a partial plan view, the small hole 15 has a perfect circular cross section and a good wall surface cylindricity. This small hole 15
The diameter of can be made smaller than the thickness of the plate member 8 by making the diameter of the prepared hole 9 smaller as described above. Even if the diameter of the small hole 15 is reduced, the punch 13
Is hardly damaged. This is because the punch 13 only scrapes off the peripheral wall surface portion 14 of the prepared hole, and the load received is much smaller than in the case of directly punching a small hole having a small diameter as described above from the plate member 8. Because.
Therefore, according to the small hole drilling method of the present embodiment, even small holes whose diameter is considerably smaller than the thickness of the plate member 8 can be easily provided. Further, when the diameter of the small hole 15 is larger than the thickness of the plate material 8, it is possible to perform a normal punching process. However, it is better to finish the prepared hole provided in advance as in the present embodiment. This has the effect of prolonging the service life. In this embodiment, the punch / laser compound machine is taken as an example, but it goes without saying that the same effect as described above can be obtained also in the punch / plasma compound machine in which the plasma processing head is mounted instead of the laser head.

In this embodiment, the thickness is 4.5 mm.
Laser processing on SPHC (hot rolled mild steel sheet) of φ
After drilling a prepared hole of 1.6 mm (upper surface side of SPHC), using a punch with a nominal size of φ1.88 m, set the punch protrusion amount to 1.0 mm below the plate material 8 and grind the peripheral wall surface part of the prepared hole once. As a result of performing the shaving process by dropping it, a small hole of φ1.83 ± 0.020 mm could be formed. The standard for the pilot hole diameter for grade 2 rolled screws is 1.81-
Since it is 1.85 mm, the small hole provided in this embodiment is suitable as a pilot hole for the second-class rolling screw for tapping the second-class rolling screw.

In order to perform this tapping processing, a tapping processing head 16 is installed below the punch processing head 3 as shown in FIG. 4, and between the punch processing head 3 and the tapping processing head 16. The plate member 8 is arranged in The tapping head 16 is provided in the main body 1
A tap 18 is planted at the center of the punching head 7, and a cylindrical pressing member 19 through which the tap 18 can be inserted is provided below the punching head 3.

In this state, as shown in FIG. 4, the plate member 8 is pressed from above by the cylindrical pressing member 19, and the tap 18 is rotated and lifted from below to tap the small hole 15. The screw holes 20 are formed in the plate member 8 by being processed.

As described above, in this embodiment, it is rational that the plate material 8 is provided with the pilot holes 9, the small holes 15, and the screw holes 20 by performing laser processing, punching processing, and tapping processing with one processing machine. .

In this embodiment, laser processing, punching and tapping are performed by one processing machine, but laser processing, punching and tapping may be performed by separate devices or manually.

As mentioned above, it is obvious that the present invention can be variously modified. Such modifications do not depart from the spirit and scope of the invention and all such modifications and changes that are obvious to those skilled in the art are included in the claims.

[Brief description of drawings]

FIG. 1 is a partially cutaway schematic perspective view of a punch / laser combined processing machine used in a small hole processing method according to an embodiment of the present invention.

FIG. 2 is a diagram showing laser processing, (a).
Is a partial cross-sectional view, and (b) is a partial plan view.

3A and 3B are views showing finishing processing, FIG. 3A is a partial sectional view, and FIG. 3B is a partial plan view.

FIG. 4 is a partial cross-sectional view showing tapping processing.

[Explanation of symbols]

 1 Punch / Laser Combined Processing Machine 2 Body Frame 3 Punch Processing Head 4 Air Spring 5 Laser Oscillator 7 Laser Processing Head 8 Plate Material 9 Prepared Hole 10 Dust Collection Duct 11 Die 12 Plate Presser 13 Punch 14 Circumferential Wall Part 15 Small Hole 16 Tapping Head 18 Tap

Claims (3)

[Claims] 1. A small hole drilling method for making a small hole in a plate material, characterized in that the plate material is first prepared by heat cutting and then prepared, and then the prepared hole is finished by punching. Processing method. 2. The small hole machining method according to claim 1, wherein the thermal cutting process and the punching process are performed using a multi-tasking machine having a thermal cutting process head and a punching head. 3. The small hole obtained by the punching is further tapped.
Or the small hole processing method described in 2.