JPS6224880A - Control system for laser beam processing - Google Patents

Abstract

PURPOSE:To process a work of a material or shape which can be processed only by the slight quantity of laser power by means of not a pulse laser but a continuously oscillating laser by inclining the work and controlling the incident laser power. CONSTITUTION:Laser beam processing is controlled by irradiating the laser beam 11 at certain angle theta on a work surface 12, increasing the reflectivity of the laser beam 13 and making incident only the laser power necessary for the actual processing as the laser beam 14 on the work surface. The work is inclined by certain angle theta by changing the position or posture of the work so as not to melt the work at a part 203 by excessively large heat input and the laser beam processing is executed by controlling the laser power, i.e., the heat input to the work so as to suppress the same in the case of, for example, cutting out the work 202 from a flat plate 201.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Present Invention] The present invention relates to a method of irradiating a surface of a processed workpiece, and particularly to a laser processing control system suitable when the type of laser oscillation is continuous oscillation.

[Background of the invention]

Recently, high-precision, high-quality processing is being realized by applying lasers to processing such as welding, cutting, and drilling. In a laser processing system, the laser output from the laser oscillator, which is the main component, is normally irradiated perpendicularly to the workpiece surface in order to minimize the reflectance (for details, see the literature, Shin Namba :Laser and Processing: Kyoritsu Shuppan, please refer to PP30.1983.) However, the laser output range is 100-400 (W) or 2
If a laser oscillation device that does not have the lower limit of the output range set to zero, such as 00 to 1000 (W), is installed in a laser processing system, the material or shape that cannot be processed without a very small amount of laser power may be To process a workpiece, it is necessary to pulse the continuous wave laser that is irradiated perpendicularly to the surface of the workpiece and suppress the laser power. However, it has been difficult to process workpieces made of special materials or shapes such as those mentioned above.

[Purpose of the invention]

The object of the present invention is to provide a control method for processing using a continuous wave laser without using a pulse laser.

[Summary of the invention]

In order to achieve the above object, the present invention utilizes the fundamental property of lasers, ``When a laser beam is irradiated onto a work surface, some percentage of the laser beam is reflected.'' As shown in Fig. 1, the continuous wave laser from the laser oscillator that was irradiating the work surface 12 is irradiated with a beam 11 at a certain angle θ to increase the reflectance of the laser beam 13.
This is a laser processing control method in which only the laser power actually required for processing is incident on the work surface as a laser beam 14.

For example, as shown in FIG.
When cutting out 02, in the conventional method, the narrow workpiece part 2
The heat input to 03 was too large, and that part often melted, making it impossible to perform the desired processing. As a means to solve this problem, the present invention proposes a method to suppress the laser power, that is, the heat applied to the workpiece by the processing worker, by changing the position and posture of the workpiece (tilting the workpiece by a certain angle θ). We are hiring.

[Embodiments of the invention]

Hereinafter, the present invention will be explained in detail with reference to Examples.

Figure 3 shows the hardware configuration of the laser processing system used in this implementation. Reaction oscillation laser device 301 processing work 302. Processing workpiece position and posture holding device 3032 Central control device 304 of the system, processing workpiece shape data storage device 1305 Laser reflectance characteristic storage device 3
06. is the terminal device 307. It consists of a light pen 308.

Furthermore, the central control unit 304 includes the following six sub-devices: a continuous wave laser device control device 305(a), and a control device 30'4(b) for a processing workpiece position/attitude holding device.
, a laser irradiation angle calculation device 304 (cl), a processing workpiece display data calculation device 304 (e), and a control device 304 (f) that controls these. The flow of treatment procedures in the water processing system will be explained below.

First, using the shape data of the workpiece stored in 305, data for displaying the processed workpiece is calculated in 304(e), and the result 41 is graphically displayed in 307 (a display example is shown in the fourth section).
(shown in figure). The user is displayed at 307 in order to decide the power of the laser to be applied to the workpiece. As shown in Figure 5, the outline of the workpiece is processed using an input device such as a light pen in several machining sections (one unit of laser power)5.
Divide into 1. Then, the power of the laser to be irradiated is set for each divided processing section using an input device such as a keyboard. The value set here and 306
The irradiation angle of the laser onto the workpiece surface is calculated in step 304(c) from the relationship between the incident angle of the laser and the reflectance as shown in FIG. 6, which is stored in . Next, 304(c)
The laser oscillation control data 301 is calculated from the angle calculated in 305 and the shape data of the workpiece stored in 305.
o 4 (a), convert the operation control data of 303 to 304
(b), respectively, and the results are 304 (d)
If the processing procedures described above are followed, heat input to the workpiece can be suppressed. Therefore, if a conventional continuous wave laser is used, it is possible to perform desired processing even on parts of the workpiece that would otherwise be melted due to excessive heat input into the workpiece.

〔Effect of the invention〕

According to the present invention, since the laser power can be adjusted by tilting the workpiece, it is possible to process workpieces of materials or shapes that cannot be processed with a small amount of laser power using a continuous wave laser without using a pulsed laser. . This makes it possible to further expand the processing application range of the laser processing system.

[Brief explanation of the drawing]

Figure 1 is a diagram showing the reflection characteristics of a laser, Figure 2 is a diagram showing a flat plate to be processed, Figure 3 is a hardware configuration diagram of a laser processing system taken up as an embodiment of the invention, and Figure 4 is a diagram showing the reflection characteristics of a laser.
5 is a diagram showing an example of displaying the shape of a processed workpiece, FIG. 5 is an explanatory diagram of a method of setting a processing section, and FIG. 6 is a diagram showing the relationship between the incident angle of the laser and the reflectance. Figure 1 Figure 2 Figure 3 Figure 30.5. to6

Claims (1)

[Claims] A laser processing system comprising a laser oscillation device, a workpiece processed by the laser oscillation device, a position/attitude holding device for the workpiece, and a control device for the holding device,
Adjusting the incident angle of the laser onto the work surface by changing the position and posture of the work by the holding device or by changing the irradiation direction of the laser output from the laser oscillation device. Characteristic laser processing control method.