JPS61286087A - Laser cutting method - Google Patents

Abstract

PURPOSE:To prevent the adhesion of molten metal on the back face and to obtain the product of high accuracy by coating the kneading matter of alcohol, graphite and powder clay on the back face of a work body and by cutting with a laser beam from the surface. CONSTITUTION:The molten metal can simply be removed by removing a kneading matter 11 because the adhesion of the molten metal by laser beam 1 to the back face of a work body 6a directly is prevented when the work body 6a that a kneading matter 11 is coated on its back face is cut with the irradiation of the laser beam 1. The kneading matter is made by mixing graphite and powder clay at the rate of 9:1 weight ratio and by kneading this mixture and methanol at 1:1 weight ratio and can be removed simply by cleaning with water after the work.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention provides a laser cutting method for cutting a workpiece with a laser beam.

[Conventional technology]

FIG. 5 is a sectional view for explaining a conventional laser cutting method. The first cylindrical body (2) of the laser processing machine through which the laser beam (1) passes is bent at a right angle in the center, and a total reflection mirror is attached to this bent part to reflect the VcVi laser beam (1). It is being A second cylinder (4) is screwed into the tip of the first cylinder (2).
) is provided with a condenser lens (5) for focusing the laser beam (1). In addition, there is a conduction port (7) on the workpiece (6) side of the second cylinder (4) from the condenser lens (5).
is provided protrudingly, and the second cylindrical body (4
) is supplied with gas. Furthermore, a small diameter nozzle (8) is formed at the tip of the second cylinder (4), and the workpiece (6) is placed in front of this nozzle (8), and a high energy density laser Processed by beam (1)11. Ru.

Next, the operation will be explained. As shown in FIG. 6, the laser beam (1) is bent by a total reflection mirror (3) so that it is irradiated perpendicularly to the workpiece (6).

The bent laser beam (1) is focused by a condenser lens (5), and passes through a nozzle (8) to irradiate the workpiece (6). At this time, by moving the workpiece (6) as shown by the arrow, the workpiece (6) can be cut into any shape. Further, the gas introduced through the communication port (7) is injected onto the workpiece (6) through the nozzle (8), and the molten or vaporized metal is removed by this gas.

In this cutting method, there is no problem with the workpiece (6) where the viscosity of the molten metal such as carbon steel or the molten oxide generated when oxygen is used as a gas is small, but when the molten metal is The situation is completely different in the case of workpieces (6) such as stainless steel and aluminum, which have extremely high viscosity.

FIG. 4 shows a cross section of a cut part when a workpiece (6) of high viscosity molten metal is cut by such a method, and (9) is a cutting groove. In this case, no matter how appropriately the laser output, processing speed, etc. are controlled, cutting @ (9)
Molten metal αQ is deposited on the back surface of the lower part of the plate, and this molten metal αQ cannot be easily removed.

[Problem that the invention seeks to solve]

As described above, in the conventional cutting method, molten metal QG tends to adhere to the back surface of the lower part of the cutting groove (9), and post-processing is required to remove it. This increases the number of processing steps and processing costs, which is a major problem especially in laser cutting of workpieces (6) such as stainless steel and aluminum.

The present invention was made to solve the above-mentioned conventional problems, and aims to provide a laser cutting method that can easily prevent the adhesion of molten metal, is extremely inexpensive, and has excellent product precision. This is what I did.

[Means for solving problems]

In the present invention, when cutting a workpiece made of a material with high viscosity of molten metal, a mixture of alcohol, graphite, and powdered clay is applied to the lower back surface of the workpiece, and a laser beam is irradiated onto the workpiece. It is designed to be cut.

[Effect]

A mixed substance of alcohol, graphite, and powdered clay was applied to the back side of the workpiece, which prevented the metal melted by the laser beam from directly adhering to the backside of the workpiece, and the mixed substance was removed after processing. do.

〔Example〕

FIG. 1 is a sectional view for explaining the present invention in detail.
) to (5), (7), and (8) are the 6th
This is exactly the same as the conventional example shown in the figure. (6a) is the workpiece,
A mixture α■ of alcohol (for example, methanol), graphite, and powdered clay is coated on the back side.

The workpiece (
When 6a) is irradiated with the laser beam (1) and cut,
As shown in FIG. 2, the kneaded material α1) is exposed to the laser beam (1
) prevents the molten metal from directly adhering to the back surface of the workpiece (6a), resulting in
Processing in which molten metal does not adhere to the back surface of a) can be performed. Even if molten metal adheres to the mixed material α■, it can be easily removed by removing the mixed material C1]).

In the example, graphite and powdered clay were mixed at a ratio of 9:1 by weight, this mixture and methanol were kneaded at a ratio of 1:1 by weight, this kneaded product was applied to the back side of the workpiece, and the laser beam was applied to the back surface of the workpiece. When cutting with a beam, very good results were obtained.

〔Effect of the invention〕

As is clear from the above explanation, the present invention applies a mixture of alcohol, graphite, and powdered clay to the back side of a workpiece, irradiates the surface of the workpiece with a laser beam, and then works with this mixture. Since the workpiece is cut, processing can be performed without molten metal adhering to the back surface. As a result, not only can highly accurate products be obtained, but the step of removing molten metal after laser processing can be omitted, and the kneaded material is extremely inexpensive, and moreover, it can be easily washed with water after processing. This method has great effects, such as being able to remove kneaded materials.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing an embodiment of the laser cutting method according to the present invention, FIG. 2 is a cross-sectional view showing the shape of the cut surface when a workpiece is cut by the laser cutting method of the present invention, and FIG. The figure is a cross-sectional view showing a conventional laser cutting method, and FIG. 4 is a cross-sectional view showing the shape of a cut surface when a blank is cut by the conventional laser cutting method. In the figure, 1 is a laser beam and 2Vi is a first cylindrical body. 3 is a total reflection mirror, 4 is a second cylindrical body, 5 is a condensing lens, 6a is a workpiece, 7 is a communication port, 8 is a nozzle, 9 is a cutting groove, 11
It is a Vi kneaded product. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (3)

[Claims] (1) In a method of cutting a workpiece with a laser beam, a mixture of alcohol, graphite, and powdered clay is applied to the back side of the workpiece, and the surface of the workpiece is irradiated with a laser beam. A laser cutting method characterized by cutting objects. (2) The laser cutting method according to claim 1, wherein methanol is used as the alcohol. (3) Claim 1, characterized in that the kneaded material is formed by mixing graphite and powdered clay at a weight ratio of 9:1, and kneading this mixture and methanol at a weight ratio of 1:1. Laser cutting method described.