JPS60979A - Laser marking apparatus - Google Patents

Abstract

PURPOSE:To prevent the generation of deficiency to the pattern on a mask, by a method wherein laser beam is split into plural beams while masks having mutually complementary configurations are inserted into split beams and respective mask images are superposed on an article to be processed. CONSTITUTION:In a laser marking apparatus for marking a commodity name, a trade mark or a product number by irradiating the surface of an article to be processed such as parts or a product with laser beam, laser beam emitted from a laser oscillator 1 is expanded to a proper beam diameter by a beam expander 2 consisting of a concave lens 21 and a convex lens 22 and split into plural beams by using a partially perious mirror 3 while masks 5, 6 having mutually comprementary patterns are inserted in the course of split beams and mask images are formed on the article 9 to be processed. By this method, the patterns corresponding to island like parts such as a figure 8, alphabets O, D or the like can be marked without generating deficiency caused by bridging.

Description

[Detailed description of the invention] Fuyuan Ming uses laser light to make parts non-contact.

This product relates to a laser marking device that engraves product names, trademarks, product numbers, etc. on products.

Conventionally, there are four methods for marking with a laser beam.The first method is to scan the laser beam and then turn off the laser beam 1 (JN-OFF).
How to move the laser beam according to the shape of the mark,
A method is known in which the conduit 3 is irradiated with a laser beam at a fixed position and the entire workpiece is moved, and a fourth method is a method in which marking is performed using a beam that passes through a mask. Nori these methods.

Regarding the first to third methods, since the moving speed of the laser beam or the workpiece is about several IQcIn per second,
Marking takes a long time. The method using the laser beam that has passed through the fourth mask has the feature that marking can be done instantly with a single pulsed laser, and it is possible to easily mark objects that are moving at high speed. However, when simultaneously irradiating a large area with 1C laser beams, a large amount of laser energy is required, and the mask needs to be strong enough to withstand the laser energy.

At the mask surface, the laser beam is spread and at the same time the mask is made of a high melting point metal material. When marking using such a mask, depending on one character, symbol, etc., you may want to leave the mask in an island shape quite often.For example, the number 8. This applies to marking the letters of the alphabet (J, D, etc.).At this time, the metal mask supports the island-shaped part (center of the letter) with a thin bridge from the periphery, so the marked letters A defect appears in the area masked by the bridge.

The purpose of non-invention is to create characters with such masks.

6. It is an object of the present invention to provide a laser marking device that does not produce any defective parts.

The laser marking device according to the invention divides a laser beam, inserts a mask into each path of the divided laser beam, and superimposes the image of the mask on the workpiece using an optical device such as a lens. Each mask is a set of masks that represent the same character or symbol with different positions of the bridge supporting the island-shaped portion in front of the character or symbol. The laser beams that have passed through all of these masks separately form images on the workpiece, and at this time, in order to compensate for each other's defects, the laser beams are marked.Next, an embodiment of the invention will be described in detail with reference to the drawings. .

FIG. 1 shows an embodiment of a laser marking device according to the invention. A laser beam emitted from a laser oscillator 1 is expanded to an appropriate beam diameter by a beam expander 2 consisting of a concave lens 21 and a convex lens 22 and reaches a partially transmitting mirror 3, where approximately half of the laser beam energy is transmitted along the original axis 11. reflected.

The energy of the flD laser beam reaches the total reflection mirror 4,
It propagates along the optical axis 12. On the original axis 11 is a mask 51
A mask 6 is placed on the original axis 12 at a position parallel to and equidistant from the processing surface of the workpiece 9.

The laser beam passes through cutout portions 51, 52, 61, 62° 63 of masks 5, 6 (shown in FIG. 2), respectively, and is imaged onto the workpiece by an imaging optical lens 7.8 ( form the number 8”).

At this time, the laser beam from the lens 7.8 is irradiated onto the workpiece 9, the workpiece surface is evaporated and removed, and marking is completed.

FIG. 3 shows the state of marking on the workpiece 9. As shown in FIG. The marking by the mask 5 is indicated by the diagonal line on the lower left. Further, the marking by the mask 6 is shown by the downward diagonal line to the right. When only one of the different masks 5 and 6 is used to fully irradiate the laser, the mark on the workpiece will have a defect. This is caused by the bridge supporting the island portion 53.54 or 64.65 of the mask. But two masks 5.6
If the respective marks are superimposed using the same method, a mark without defects is formed as shown in FIG.

As described above, according to the invention, complete marking of characters, symbols, etc. can be achieved, and erroneous judgments at the time of mark reading can be avoided.

In addition, in the above-mentioned practical example, a case was explained in which the laser beam irradiated to two masks is divided almost equally.
Depending on how the mask is created, it is also possible to change the ratio of laser beam divisions. Also, when marking more complex patterns, symbols, etc., the number of beam divisions may be extended to two or more. It goes without saying.

[Brief explanation of drawings]

Fig. 1 is a diagram showing an embodiment of the invention, Fig. 2 is a mask used in the laser marking device shown in Fig. 1, and Fig. 3 is a diagram showing the state of marking on a workpiece. . 1... Laser oscillator, 2... Beam exno-kunda, 3... Partially transmitting mirror, 4...
・Total reflection mirror, 5.6...Mask, 7.8...
...Imaging optical device.

Claims (1)

[Claims] In a laser marking device comprising a laser oscillator, a mask for emitting a portion of the laser beam emitted from the laser oscillator, and an optical device for forming an image of the mask on a workpiece, the laser beam is divided into a number of values. Laser marking iron 11. includes means for inserting mutually complementary masks into the optical path of each divided laser beam, and aligning the images of the respective masks onto the workpiece. .