JPS589782A - Cutting method by laser - Google Patents

Abstract

PURPOSE:To cut a small aquare hole of good dimensional accuracy by sticking a metallic plate having a specified through hole fast to a material to be worked and performing laser cutting. CONSTITUTION:Metallic plates 5 having through holes which are similar in shape with the hole to be cut in a material to be worked 2 are sttuck fast to the upper and rear surfaces of the material 2, and irradiated by an oscillated laser beam 1. The laser beam is oscillated in the through holes of the metallic plates 5 with locus 7 to perform laser cutting. When laser cutting of a small square hole is performed, thermally influenced part around cut part becomes remarkably small as the circumference of the cut part is sheltered by the metallic plates 5 having sufficient heat capacity and dimensional accuracy of cutting can be fully maintained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a laser cutting method for accurately cutting a small square hole using a laser beam.

Eleventh? A conventional laser cutting method using IL-1 will be explained. In Fig. 1, (1) is a laser beam outputted by a laser oscillator (21 pieces), and a small square hole is formed by the laser beam (INC). (5a) (5b) (ise) is the cutting line of the workpiece 121 that has already been cut (4a) (4b) (4c
) indicates the planned cutting line of the shape to be cut. Note that FIG. 1 0) is a partially enlarged view showing the cutting part of the workpiece (2) in detail, and shows that it is scheduled to be cut by the laser beam (11).
m (cut larger than 41, broken line C3) appears.

Next, a conventional laser cutting method will be explained.

FIG. 1 (In AR, the laser beam (ti) focused by Lanes etc. is focused on the surface of the workpiece (21) and instantly evaporates and removes the workpiece (21, 4 or laser beam 01.

Cutting is achieved by moving it according to the shape of the required cutting line (41). At this time, if the distance between the cutting part (3a) and the adjacent cutting part (3b) is extremely close, K
id, the portion sandwiched between the cut portion (5a) and the cut portion (5b) was melted, the surface was discolored due to the influence of heat, and the material vC clustered. In addition, since the width that can be generally cut by laser cutting is about 0.2n to 0.6a, the cutting schedule 41 (41
is rectangular and the width is about 1.0 mm, the planned cutting line (41
When the laser beam is moved along K, the shape of the cut section (3) becomes rounded at the corners due to thermal saturation, and the straight section becomes wavy, making it impossible to maintain sufficient dimensional accuracy. there were.

Therefore, according to the conventional laser cutting method, sufficient dimensional accuracy cannot be obtained for cutting small square holes or adjacent parts. Method A requires complex control such as laser beam output control and workpiece movement speed control, which increases the processing steps and processing time and complicates the processing equipment.

This invention was made in order to eliminate the drawbacks of the conventional methods as described above, and a metal plate having a through hole f having the same shape as the processing shape is placed on the surface of the workpiece to be irradiated with the laser beam. It is designed so that laser cutting can be performed while the parts are in close contact with each other.

The aim is to provide a laser cutting method with excellent processing accuracy.

An embodiment of the present invention will be described below with reference to the drawings. Second
Figure (A) shows the arrangement of each component, and Figure 2 (0) shows the movement of the laser beam. That is, in FIG. 2(A), t(
5a) The workpiece (21) is a metal plate that is in close contact with the irradiation surface of the laser beam (11), and has a through hole (61) having the same shape as the shape to be cut.

Further, (5b) is a metal plate closely attached to the back surface of the workpiece (21).The metal plate (5a) (
The through holes (6) of Sb) are arranged in the same part.

In FIG. 2P), (7) shows the movement of the laser beam (!1) within the spacing of the through-hole (6).

Figure 3 also shows the through hole (6) provided in the metal plate (5).
The width of one through hole (6) is as follows.
It is narrowest at the part where it comes in close contact with the workpiece (21).

Next, the method of this invention will be explained. First.

As shown in Figure 12 (A), on the front and back surfaces of the workpiece (2).

A through hole (6) that has the same shape as the workpiece (2) to be cut.
The metal plate (54) having a
) is vibrated within the interval between the through holes (6) with a trajectory as shown in Figure 2 CB)K to perform laser cutting. When laser cutting a small square hole using this method, the cut portion Metal plate with sufficient surrounding heat capacity (5)
The heat-affected zone around the periphery of the cutting part is significantly reduced.

In addition, K is set so that the dimensional accuracy of cutting can be maintained sufficiently.

In addition, as shown in FIG. 3, the through hole (6) of the metal plate (5)
), the metal plate (5) is in close contact with the workpiece (2).
By creating a shape that is narrowest at the dry end.

Since the end portion of the voice hole (6) is sufficiently irradiated with the laser beam (seal), the effect of further improving the dimensional accuracy of the cutter can be obtained.

In the above embodiment, rectangular cutting has been described, but the same effect can be achieved for other machining shapes as long as the workpieces are machined in close proximity.

As described above, according to the method of the present invention, a metal plate having a predetermined through hole and sufficient surface heat capacity is brought into close contact with the surface of the workpiece, and laser cutting is performed. The effect is that the affected area is reduced and good cutting quality with one dimension accuracy can be obtained.

[Brief explanation of drawings]

Figure 1 is a diagram for explaining the conventional laser □ cutting method.
FIG. 2 is a diagram for explaining a laser cutting method according to one embodiment of the present invention, and FIG. 3 is a cross-sectional side view 'C of a metal plate showing another embodiment of the present invention. 0, Ruther beam, (21 workpiece, (5) metal plate, (
6) Through hole. In the figures, the same reference numerals indicate the same or corresponding parts. Applicant: Makoto Ishiita, Director of the Agency of Industrial Science and Technology.

Claims (1)

[Claims] 0) In a method of cutting a workpiece by irradiating it with a laser beam, a metal plate having a through hole having the same shape as the shape to be cut is placed on the laser beam irradiation surface of the workpiece. A laser cutting method characterized by cutting the workpiece by irradiating the laser beam with the workpiece in close contact with the workpiece. (21) The laser cutting method according to claim 01, characterized in that the metal plate is brought into close contact with the back surface of the laser beam irradiation surface. (3) The distance between the through holes provided in the metal plate is The laser cutting method according to claim 01, characterized in that the laser cutting method is narrowest at the part in contact with the object surface. Claim No. 01, No. (2: No. 31) is a laser cutting method according to No. 31. A laser cutting method according to any one of claims 0, 21, 3, and 41.