KR101517602B1 - Optical head for laser machining - Google Patents

Abstract

The present invention relates to an optical head for laser processing, which can process materials of various sizes without departing from the space limitation by injecting an antioxidant gas with a nozzle and improve the reliability of processing through cleaning, A first tube communicating with the first nozzle to supply the antioxidant gas to the first nozzle, and a second tube communicating with the first nozzle to spray the cleaning gas to the workpiece so as to clean the workpiece, A second nozzle for spraying the cleaning gas and surrounding the first nozzle before the first nozzle discharges the oxidation-preventing gas and the laser, and a second tube communicating with the second nozzle to supply the cleaning gas, And an optical head for laser processing.

Description

[0001] The present invention relates to an optical head for laser machining,

The present invention relates to an apparatus and a method for processing a workpiece using a laser, and more particularly, to an optical head for laser processing.

In general, the processing of materials using lasers is rapidly expanding in application fields throughout the industry. The superior characteristics of laser processing in materials processing are replacing existing processes in heat treatment, welding, and drilling processes, thereby improving quality, reliability and productivity. Important advantages of such laser machining include precision, process flexibility, non-contact machining, and minimal thermal effects.

However, such conventional laser processing apparatuses, particularly laser polishing apparatuses, have not been able to process materials in various sizes due to space constraints by processing materials in the chamber, and can not perform cleaning processes before processing.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems and it is an object of the present invention to provide a cleaning method and a cleaning method capable of processing materials of various sizes, An object of the present invention is to provide an optical head for laser processing. However, these problems are exemplary and do not limit the scope of the present invention.

According to one aspect of the present invention, there is provided an antioxidative gas cleaning apparatus comprising: a first nozzle coaxially discharging an antioxidant gas and a laser to prevent oxidation of a workpiece; a first nozzle communicating with the first nozzle to supply the antioxidant gas to the first nozzle A second nozzle for spraying a cleaning gas to the workpiece to clean the workpiece and spraying the cleaning gas before the first nozzle discharges the oxidation preventing gas and the laser, And a second tube communicating with the second nozzle to supply the cleaning gas.

The end portions of the first nozzle and the second nozzle may be disposed adjacent to each other.

The second nozzle may eject the cleaning gas after ejecting the laser and the oxidation-preventing gas through the first nozzle.

The second nozzle may eject the cleaning gas to eject the laser and the antioxidant gas through the first nozzle and then quench the workpiece.

According to an embodiment of the present invention as described above, an oxidation preventing gas is injected into a nozzle to process materials of various sizes out of the restriction of a space, and an optical head for laser processing Can be implemented. Of course, the scope of the present invention is not limited by these effects.

1 is a conceptual diagram schematically showing an optical head for laser processing according to an embodiment of the present invention.
2 is a cross-sectional view schematically showing a double nozzle of an optical head for laser processing according to an embodiment of the present invention.
Fig. 3 is a plan view schematically showing an end portion of the double nozzle of Fig. 2; Fig.
Figs. 4 and 5 are flowcharts schematically showing a processing procedure using the above-described optical head for laser processing.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be understood, however, that the invention is not limited to the disclosed embodiments, but may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, Is provided to fully inform the user. Also, for convenience of explanation, the components may be exaggerated or reduced in size.

FIG. 1 is a conceptual view schematically showing an optical head for laser processing according to an embodiment of the present invention, and FIG. 2 is a schematic cross-sectional view showing a part of an optical head for laser processing according to an embodiment of the present invention. The optical head for laser processing according to this embodiment includes a first nozzle 110, a first tube 120, a second nozzle 130, and a second tube 140. Prior to a specific description of the nozzles, the optical head for laser processing according to this embodiment will be described.

The main body 300 may be combined with various components for laser processing. For example, the main body 300 is coupled to various components in the form of a housing, a frame, or the like.

The optical fiber 400 guides a laser generated from a laser source (not shown) for generating a laser to the inside of the main body 300. For this purpose, the optical fiber 400 is connected to a laser source and the other side is inserted into the main body 300 Respectively. The optical fiber 400 is coupled to the main body 300 through an optical coupler 410 to prevent the laser from being scattered into the main body 300. Here, the optical fiber 400 can be coupled at a position substantially perpendicular to the nozzle.

The scanner 200 reflects or deflects the laser beam guided to the main body 300 through the optical fiber 400 and guides the laser beam to the nozzle. For example, as shown in the figure, the scanner 200 can change the optical path of the laser using a plurality of total reflection mirrors. The scanner 200 can form a shape on the irradiation surface of the work W so as to have a specific pattern by rotating a plurality of mirrors or changing an angle. Further, the scanner 200 can change the diameter of the laser beam. To this end, the scanner 200 includes at least one driver (not shown).

The laser beam guided to the main body 300 and passed through the scanner 200 is emitted as a workpiece W. At this time, the laser beam is emitted to the workpiece W through the first nozzle 110. The first nozzle 110 is coupled to one side of the main body 300 and extends toward the workpiece W so that the laser is emitted through the inside thereof. Describing the processing of the workpiece W by emitting a laser, various operations such as cutting the workpiece W can be performed. In particular, the workpiece W can be polished.

Further, the first nozzle 110 coaxially cools the antioxidant gas, which prevents oxidation of the workpiece W, with the laser. Specifically, when the workpiece W is processed by a laser, the workpiece W is melted by the laser and reacted with oxygen in the atmosphere to be oxidized. In order to prevent this, antioxidant gas is sprayed on the machined surface during laser machining. In other words, the oxidation preventing gas prevents oxygen from approaching the machined surface of the workpiece W, thereby preventing oxidation of the workpiece W. At this time, the antioxidant gas is emitted slightly earlier than the laser or emitted almost simultaneously.

At this time, when the nozzle for emitting the laser and the nozzle for spraying the antioxidant gas are different, since the angle at which the laser is emitted and the angle at which the antioxidant gas is injected are different, the surface of the workpiece W to be processed by the laser, The surface of the workpiece W where the gas blocks oxygen may be different. As a result, the oxidation-preventing gas can not completely block the oxygen coming into contact with the working surface. In order to prevent this, according to an embodiment of the present invention, when the workpiece W is laser-processed, the laser and the oxidation-preventing gas are coaxially injected into one nozzle.

The first pipe 120 communicates with the first nozzle 110 to supply the oxidation-preventing gas to the first nozzle 110. For example, the first tube 120 is connected to the first tube 500, one end of which is coupled to the side of the first nozzle 110, and the other end of which is extended from a supply part (for example, a bomb) .

The above-described antioxidant gas may contain an inert gas such as argon, helium, or the like, or may contain nitrogen.

The second nozzle 130 surrounds the first nozzle 110. That is, the second nozzle 130 is provided outside the first nozzle 110, and the first nozzle 110 and the second nozzle 130 constitute the double nozzle 100. At this time, the end of the second nozzle 130 and the end of the first nozzle 110 are adjacent to each other. That is, the first nozzle 110 and the second nozzle 130 are located at substantially the same height from the work W.

The second nozzle 130 injects the cleaning gas into the work W so as to clean the work W and injects the cleaning gas before the first nozzle 110 releases the antioxidant gas and the laser. The workpiece W is often subjected to a process such as cutting or polishing by a machine tool such as a milling machine before laser processing. The workpiece W that has been subjected to the mechanical polishing process may not have a smooth laser process due to dust, cutting oil, and cutting chips remaining on the surface.

Accordingly, the cleaning gas is jetted with the work W to remove the dust and cutting oil remaining on the surface of the work W, and the work W is processed by the laser. This can improve the precision of laser machining.

Additionally, the second nozzle injects cleaning gas after laser machining. By spraying the cleaning gas after the laser processing, it is possible not only to remove the by-products present on the processed surface after the laser processing, but also to induce the effect of cooling the heated work W to increase the hardness.

On the other hand, when the cleaning gas is jetted from nozzles existing at positions different from the nozzles which emit the laser, the surface of the workpiece W from which the cleaning gas is jetted is different from the surface of the workpiece W . In order to prevent this, the second nozzle 130 may be disposed so as to surround the first nozzle 110 so that the jetting region of the cleaning gas and the processing region of the laser are substantially coincident with each other.

The second pipe 140 communicates with the second nozzle 130 to supply the cleaning gas to the second nozzle 130. For example, the second tube 140 is connected to the second tube 600, one end of which is coupled to the side of the second nozzle 130, and the other end of which is extended from a supply part (for example, a bomber)

The cleaning gas described above may include carbon dioxide gas. Here, when the carbon dioxide gas is injected through the nozzle, the carbon dioxide gas is compressed and expanded to become dry ice particles, which are injected into the material to cause a cleaning action. The dry ice quenches the material. At this time, the work (W) including the metal material can obtain the effect of increasing the hardness by the quenching effect.

3 schematically shows an end of nozzles of an optical head for laser processing according to an embodiment of the present invention. The distance D between the second nozzle 130 and the first nozzle 110 may be smaller than the diameter R of the first nozzle 110. Specifically, the cleaning gas must be sprayed at a high speed in order to remove cutting oil and cutting chips remaining on the surface of the work W. Accordingly, the interval D between the first nozzle 110 and the second nozzle 130 can be narrowed to increase the jetting speed of the cleaning gas.

Figs. 4 to 5 are flowcharts showing the optical heads for laser processing according to the above-described embodiments in order of time.

Referring to FIG. 4, when the workpiece W is mechanically machined, a cleaning gas is sprayed through the second nozzle 130 to remove cutting oil and cutting chips. Unlike the cutting process, the surface of the workpiece W is processed uniformly without the presence of cutting oil and cutting chips on the surface of the workpiece W. Specifically, in the laser cutting process, the cutting oil or the like may be burnt together with the workpiece W. In the laser machining process, however, if the cutting oil exists on the surface of the workpiece W, W are not uniformly processed. Accordingly, in order to uniformly process the surface of the work W, a cleaning gas is sprayed on the work W to trim the surface of the work W.

Referring to FIG. 5, a workpiece W is processed by coaxially injecting laser and antioxidant gas through a first nozzle 110 after injecting a cleaning gas. Since the laser machining process instantaneously melts the surface of the workpiece W, the reaction with oxygen is fast and the oxidation reaction easily occurs. Therefore, the emission of the laser and the injection of the oxidation preventing gas are coaxial to prevent the oxidation reaction.

And selectively injects the cleaning gas through the second nozzle 130. Foreign substances that may be present in the workpiece W after the processing step can be easily removed through a continuous process of spraying the cleaning gas, and a separate cleaning process using chemicals can be omitted, thereby simplifying and streamlining the process.

Particularly, it is possible to quench the workpiece by spraying the cleaning gas through the second nozzle 130 after processing. As a result, the quenching effect is generated as described above, and the hardness of the work W can be improved.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the invention. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

100: double nozzle 110: first nozzle
120: first tube 130: second nozzle
140: Second tube 200: Scanner
300: main body 400: optical fiber
410: Optocoupler 500: First tube
600: second tube

Claims (4)

main body;
A first nozzle coupled to the body and coaxially discharging an antioxidant gas and a laser to prevent oxidation of the workpiece;
A first tube communicating with the first nozzle to supply the antioxidant gas to the first nozzle;
A second nozzle surrounding the first nozzle and spraying a cleaning gas containing carbon dioxide gas to the workpiece before and after laser processing to clean the workpiece;
A second tube communicating with the second nozzle to supply the cleaning gas;
An optical fiber for supplying a laser to the first nozzle and transmitting the laser generated from the laser source to the main body; And
And a scanner installed in the main body and guiding a laser guided to the main body through the optical fiber to the first nozzle to polish the workpiece,
Wherein the second nozzle is configured to clean the surface of the workpiece by spraying a cleaning gas to the workpiece prior to polishing through the first nozzle and to spray the cleaning gas through the first nozzle to clean the surface of the workpiece And the optical head is configured to be cooled.
The method according to claim 1,
And the end portions of the first nozzle and the second nozzle are arranged so as to be adjacent to each other.
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