KR20230118759A - Nozzle for laser processing - Google Patents

Abstract

The present invention provides a nozzle for laser processing capable of efficiently processing a workpiece by increasing the straightness of a shield gas that protects a laser beam and an assist gas to ensure a stable straight distance of a laser beam that propagates the assist gas into a medium. The present invention for this purpose is connected to the processing head, the first nozzle through which the first flow path is formed along the irradiation direction of the laser beam; and a second nozzle disposed to surround the first nozzle and having a second passage formed between an outer surface of the first nozzle and a second passage for guiding shield gas. At this time, the exits of the first flow passage and the second flow passage are disposed at the same position along the irradiation direction of the laser beam, and the second flow passage extends parallel to the irradiation direction of the laser beam from the exit and extends toward the center of the first nozzle. It includes a vertical flow passage for guiding the guided shield gas to be sprayed parallel to the irradiation direction of the laser beam.

Description

Nozzle for laser processing {NOZZLE FOR LASER PROCESSING}

The present invention relates to a nozzle for laser processing, and more particularly, to a nozzle for laser processing that enables efficient processing of a workpiece by increasing the transmission distance and straightness of a laser beam irradiated underwater.

A laser processing device processes a workpiece by radiating a laser beam oscillated from a laser oscillator and condensed toward a workpiece through a nozzle installed at a lower end of a processing head.

On the other hand, the assist gas is ejected from the nozzle toward the workpiece along with irradiation of the laser beam. The assist gas plays an important role in improving the processing quality and processing performance of the workpiece.

In addition, the processing quality is affected by various cutting variables, and the component of the laser processing apparatus that affects the processing quality among the processing variables is the nozzle installed at the lower end of the processing head.

For example, a method of cutting stainless steel or aluminum as a workpiece uses nitrogen as an assist gas. Conventionally, examination of the flow path diameter in the nozzle has been conducted so that the assist gas using nitrogen is injected at high pressure, but examination of the flow path shape of the nozzle has not been particularly considered.

On the other hand, when the laser processing apparatus is operated in water, since the assist gas is raised by the difference in density, a problem occurs in that the straight line distance of the laser beam using the assist gas as a medium is reduced. To this end, a method of protecting the assist gas from surrounding fluid (water) is taken while spraying the shield gas to the periphery of the assist gas together.

However, only the diameter of the passage in the nozzle is studied so that the shield gas is also injected at the same high pressure as the assist gas, and the examination of the passage shape of the nozzle is not particularly considered. Therefore, there is a problem in that the assist gas is not sufficiently protected from the surrounding fluid due to mutual interference generated at the boundary between the shield gas and the assist gas.

Republic of Korea Patent Registration No. 1946898 (2019.02.11. Notice)

An object of the present invention for solving the above problems is to increase the linearity of the shield gas that protects the laser beam and the assist gas to guarantee a stable straight distance of the laser beam that propagates the assist gas to the medium so that the workpiece can be efficiently processed. It is to provide a nozzle for laser processing.

The problem to be solved by the present invention is not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below. .

A nozzle for laser processing according to an embodiment of the present invention for solving the above problems is connected to the processing head, the first nozzle through which the first flow path is formed along the irradiation direction of the laser beam; and a second nozzle disposed to surround the first nozzle and having a second passage formed between an outer surface of the first nozzle and a second passage for guiding shield gas.

At this time, the outlets of the first flow path and the second flow path may be disposed at the same location along the irradiation direction of the laser beam.

In addition, the second flow path extends parallel to the irradiation direction of the laser beam from the outlet, and is a vertical flow path for guiding the shield gas guided toward the center of the first nozzle to be sprayed in a state parallel to the irradiation direction of the laser beam. wealth may be included.

The second flow path may further include a horizontal flow path disposed upstream of the vertical flow path and guiding the shield gas toward the center of the first nozzle in a horizontal state.

In addition, an end of the first nozzle forming the vertical passage part may have an outer surface parallel to the irradiation direction of the laser beam.

In addition, a second passage extending from the second nozzle to surround the barrel connecting the processing head and the first nozzle and communicating with the second passage is formed between the outer surface of the barrel and a second passage extending. A nozzle extension may be further included.

In addition, an inlet of the second passage may be provided in the second nozzle extension, and in this case, the inlet of the second passage is disposed at a position spaced apart from the outlet of the second passage along the irradiation direction of the laser beam. , It may be disposed in an upper region adjacent to the processing head based on a horizontal line intersecting the central part in the longitudinal direction of the barrel part.

In addition, the second nozzle extension part may be coupled such that an upper end thereof surrounds at least a portion of a mounting table coupled to the processing head or the barrel part. At this time, the second nozzle extension may have an inlet of the second passage, and in this case, the inlet of the second passage is located at a position maximally spaced from the outlet of the second passage along the irradiation direction of the laser beam. To be disposed, it may be disposed at the same position as the lower end of the mount along the irradiation direction of the laser beam.

In addition, a first airtight member disposed between the mounting table and the second nozzle extension part, and a second airtight member disposed between the mounting table and the barrel part may be further included.

In addition, the second nozzle and the second nozzle extension may be made of a single body.

In addition, the second nozzle may further include a water pressure sensor for measuring the water depth so that the supply pressure of the shield gas supplied to the second passage can be adjusted according to the water depth.

According to the present invention, by improving the flow path for spraying the shield gas, the straightness of the sprayed shield gas is increased to guarantee a stable straight distance of the laser beam that propagates the assist gas to the medium, and from this, it is possible to efficiently process the workpiece. there is.

The effects of the present invention are not limited to the above effects, and should be understood to include all effects that can be inferred from the detailed description of the present invention or the configuration of the invention described in the claims.

1 is an exemplary cross-sectional view showing a nozzle for laser processing according to an embodiment of the present invention.
FIG. 2 is an enlarged exemplary view of part A of FIG. 1 .
3 is an exemplary diagram for explaining a state of dispensing a shield gas according to an embodiment of the present invention.
4 is a cross-sectional view for explaining the configuration of a second nozzle extension according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention in which the above-described problem to be solved can be realized in detail will be described with reference to the accompanying drawings. In describing the present embodiments, the same name and the same reference numeral may be used for the same configuration, and additional description accordingly may be omitted.

1 is a cross-sectional view showing a nozzle for laser processing according to an embodiment of the present invention, FIG. 2 is an enlarged example view of part A of FIG. 1, and FIG. 3 shows a spraying state of a shield gas according to an embodiment of the present invention. It is an example diagram for explanation.

1 to 3, the nozzle for laser processing according to this embodiment includes a first nozzle 100 and a second nozzle 200.

The first nozzle 100 is connected to the processing head 10 and may have a first passage 110 penetrating along the irradiation direction D1 of the laser beam L.

The first flow passage 110 may inject the assist gas AG at the same time as irradiating the laser beam L received from the processing head 10 toward the workpiece.

Here, the barrel part 15 may be disposed between the processing head 10 and the first nozzle 100 . The barrel part 15 extends long in the irradiation direction D1 of the laser beam L, and transmits the laser beam L and the assist gas AG transmitted from the processing head 10 to the first nozzle 100. It can be guided to the 1 euro 110 side.

When the cutting operation is performed underwater, the laser beam L may be exposed to water and absorbed by the water, resulting in a decrease in output. Accordingly, when the laser beam L is advanced using the assist gas AG as a medium, stable progression of the laser beam L can be ensured and output degradation can be prevented. Nitrogen gas may be used as the assist gas AG.

The second nozzle 200 is disposed to surround the first nozzle 100 and may form a second passage 210 between the outer surface of the first nozzle 100 and the second nozzle 200 .

The second flow path 210 may inject shield gas SG supplied from the outside toward the workpiece, and the shield gas SG passing through the second flow path 210 passes through the first flow path 110. While surrounding the assist gas AG, it may proceed toward the workpiece together with the assist gas AG.

As the shield gas (SG) wraps around the assist gas (AG) and proceeds along with the assist gas (AG) in the irradiation direction (D1) of the laser beam (L), the assist gas (AG) moves to the surrounding fluid (water). It is possible to suppress exposure to and prevent the assist gas AG from rising without reaching the processing surface of the workpiece due to the difference in density or the speed of the assist gas AG being reduced. Accordingly, the distance at which the assist gas AG sprayed from the first nozzle 100 can travel straight toward the workpiece increases, and then the straight travel distance of the laser beam L using the assist gas AG as a medium. can also be increased. Compressed air may be used as the shield gas (SG).

Meanwhile, the outlet 111 of the first flow path 110 and the outlet 211 of the second flow path 210 according to the present embodiment are disposed at the same position as each other along the irradiation direction D1 of the laser beam L. .

At this time, the second flow path 210 according to the present embodiment may include a vertical flow path portion 212 .

The vertical passage part 212 may extend parallel to the irradiation direction D1 of the laser beam L from the outlet 211 of the second passage 210 .

The vertical passage part 212 converts the flow of the shield gas SG guided from the upstream of the second passage 210 toward the center of the first nozzle 100 so that the laser beam L passes through the outlet 211. The shield gas SG may be sprayed parallel to the irradiation direction D1.

The vertical passage part 212 may be formed by a part of the vertical outer surface of the first nozzle 100 and a part of the vertical inner surface of the second nozzle 200, and may be formed in the irradiation direction D1 of the laser beam L. ) may have a constant channel cross-sectional area along.

When the shield gas SG is sprayed parallel to the irradiation direction D1 of the laser beam L through the vertical passage part 212, the straight line distance of the shield gas SG can be increased, and thus assist The distance at which the gas AG can be protected is increased and the density difference of the assist gas AG can be reduced. Then, the straight line distance of the laser beam L traveling using the assist gas AG as a medium can also be increased.

In addition, the second passage 210 according to the present embodiment may further include a horizontal passage portion 213 .

The horizontal passage part 213 may be disposed upstream of the vertical passage part 212, and converts the flow of the shield gas SG guided from the upstream of the second passage 210 to the vertical passage part 212 to control the flow. 1 can be guided in a horizontal state toward the center of the nozzle 100.

The horizontal passage part 213 may be formed by a part of the horizontal outer surface of the first nozzle 100 and a part of the horizontal inner surface of the second nozzle 200 .

As a result, the shield gas SG in the second flow path 210 is partially bent from a horizontal state to a vertical state of the first nozzle 100 and a portion of the outer surface of the second nozzle 200 bent from a horizontal state to a vertical state. After sequentially passing through the horizontal passage part 213 and the vertical passage part 212 formed by a part of the inner surface, it is injected through the outlet 211.

Meanwhile, as described above, the end 130 of the first nozzle 100 forming the vertical flow passage 212 may have an outer surface parallel to the irradiation direction D1 of the laser beam L.

Unlike the drawing, if the end 130 of the first nozzle 100 is formed in an upper and lower shape so that the outer surface is inclined, the shield gas SG is formed at the end 130 of the first nozzle 100. It enters the assist gas AG side along the outer surface of the picture, so that the progress of the assist gas AG may be interfered with. Then, not only the distance capable of protecting the assist gas AG is reduced, but also the density difference of the assist gas AG increases, so that the straight line distance of the laser beam L traveling using the assist gas AG as a medium also decreases. do. Therefore, by forming the outer surface of the end 130 of the first nozzle 100 parallel to the irradiation direction D1 of the laser beam L, the straight line distance of the laser beam L can be effectively increased.

4 is a cross-sectional view for explaining the configuration of a second nozzle extension according to an embodiment of the present invention.

Referring further to FIG. 4 , the nozzle for laser processing according to the present embodiment may further include a second nozzle extension 300 .

The second nozzle extension part 300 may extend from the second nozzle 200 and may be disposed to surround the barrel part 15 connecting the processing head 10 and the first nozzle 100 . The second nozzle extension part 300 may form a second passage extension part 310 between the outer surface of the barrel part 15 and the second passage extension part 310 may form the second passage part 210. can be connected with

At this time, the second nozzle extension 300 according to the embodiment may be formed of a single body with the second nozzle 200. Of course, the second nozzle extension 300 and the second nozzle 200 may be individually configured and coupled by a separate fastening unit.

Also, the second nozzle extension part 300 according to the embodiment may be coupled such that an upper end thereof surrounds at least a portion of the mount 16 coupled to the processing head 10 or the barrel part 15 .

Mounting table 16 according to this embodiment may include a body portion 16a and a flange portion 16b. The body portion 16a forms the lower end of the mount 16 and may be disposed to extend in the direction D1 of irradiation of the laser beam L and surround the barrel portion 15 . The flange portion 16b forms the upper end of the mount 16 and extends outward from the upper end of the main body 16a, and the upper surface thereof may be coupled to the processing head 10. At this time, the second nozzle extension part 300 may be disposed such that an upper end thereof surrounds the main body part 16a of the mounting table 16 .

When configured by combining the second nozzle extension part 300 with the mount 16 as described above, the nozzle for laser processing according to the present embodiment may further include a first confidential member 410 and a second confidential member 420. can

The first airtight member 410 is disposed between the mount 16 and the second nozzle extension 300 so that external fluid (water) passes through the gap between the mount 16 and the second nozzle extension 300. Inflow into the second flow path 210 may be blocked.

The second airtight member 420 is disposed between the mount 16 and the barrel part 15 to block external fluid from flowing into the second passage 210 through the gap between the mount 16 and the barrel part 15. can

O-rings may be used as the first airtight member 410 and the second airtight member 420 .

Meanwhile, the inlet 311 of the second flow passage 210 may be provided in the second nozzle extension 300 .

A plurality of inlets 311 of the second flow path 210 may be provided, spaced apart at equal intervals along the circumferential direction. Then, the shield gas SG pressurized from the outside and passing through the inlet 311 can be quickly filled with a uniform pressure along the circumferential direction of the second flow path 210 .

And, as an example, the inlet 311 of the second passage 210 is disposed at a position spaced apart from the exit 211 of the second passage 210 along the irradiation direction D1 of the laser beam L so that the barrel part ( 15) may be disposed in an upper region adjacent to the processing head 10 based on the horizontal line HL crossing the center in the longitudinal direction (radiation direction of the laser beam).

Unlike the drawing, if the inlet 311 of the second flow path 210 is disposed at a position relatively adjacent to the outlet 211 of the second flow path 210, the shield gas (SG) passing through the inlet 311 ) is injected to the outlet 211 of the second flow path 210 in a state where sufficient pressure equilibrium is not maintained in the second flow path 210. Then, the straight distance and straightness of the shield gas SG toward the workpiece This lowers the protective effect of the assist gas AG described above.

Accordingly, the horizontal line HL crossing the central part in the longitudinal direction of the barrel part 15 is arranged so that the inlet 311 of the second passage 210 is disposed at a position relatively spaced from the outlet 211 of the second passage 210. By placing it in the upper area adjacent to the processing head 10 based on , the shield gas (SG) passing through the inlet 311 is quickly filled in the second flow path 210 to maintain pressure equilibrium, and then the vertical flow path Through the unit 212 and the outlet 211 can be injected at a set uniform pressure. Then, the straightness and distance of the shield gas SG toward the workpiece may be increased.

In addition, as another example, as shown, the inlet 311 of the second flow path 210 is maximally spaced apart from the outlet 211 of the second flow path 210 along the irradiation direction D1 of the laser beam L. It may be disposed at the same position as the lower end of the body part 16a of the mount 16 along the irradiation direction D1 of the laser beam L to be disposed at the same position.

In this way, by disposing the inlet 311 of the second flow path 210 at a position maximally spaced from the exit 211 of the second flow path 210 along the irradiation direction D1 of the laser beam L, the entrance 311 ) The shield gas (SG) passing through is filled in the second flow path 210 without being dispersed in the opposite direction of the outlet 211 to maintain pressure equilibrium in a quick time, and then the vertical flow path portion 212 and the outlet ( 211), it can be quickly sprayed with a uniform pressure set.

Meanwhile, the nozzle for laser processing according to the present embodiment may further include a water pressure sensor.

The water pressure sensor may be installed in the second nozzle 200 and measure the water depth so that the supply pressure of the shield gas SG supplied to the second passage 210 is adjusted according to the water depth. Therefore, by appropriately adjusting the injection pressure of the shield gas SG according to the depth of the workpiece to be processed by underwater laser processing, the function of the shield gas SG described above can be more effectively expressed.

As described above, the preferred embodiments of the present invention have been described with reference to the drawings, but those skilled in the art can make various modifications to the present invention within the scope not departing from the spirit and scope of the present invention described in the claims below. may be modified or changed.

100: first nozzle
110: 1st euro
111: first nozzle exit
200: second nozzle
210: second euro
211: second nozzle exit
212: vertical passage part

Claims (9)

A first nozzle connected to the processing head and through which a first passage is formed along the irradiation direction of the laser beam; and
A second nozzle disposed to surround the first nozzle and having a second flow path formed between an outer surface of the first nozzle and a second flow path for guiding shield gas;
The outlets of the first passage and the second passage are disposed at the same position along the irradiation direction of the laser beam,
The second passage extends parallel to the irradiation direction of the laser beam from the outlet and includes a vertical passage portion for guiding the shield gas guided toward the center of the first nozzle to be sprayed in a state parallel to the irradiation direction of the laser beam. A nozzle for laser processing, characterized in that for doing. According to claim 1,
The second passage is disposed upstream of the vertical passage and further comprises a horizontal passage for guiding the shield gas toward the center of the first nozzle in a horizontal state. According to claim 1,
The nozzle for laser processing, characterized in that the end of the first nozzle forming the vertical passage portion has an outer surface parallel to the irradiation direction of the laser beam. According to claim 1,
A second nozzle extension extending from the second nozzle to surround the barrel connecting the processing head and the first nozzle, and having a second passage extension formed between the outer surface of the barrel and communicating with the second passage. A nozzle for laser processing, characterized in that it further comprises a part. According to claim 4,
The second nozzle extension is provided with an inlet of the second flow path,
The entrance of the second passage is located in an upper region adjacent to the processing head based on a horizontal line intersecting the center of the longitudinal direction of the barrel so that the entrance of the second passage is disposed at a position spaced apart from the exit of the second passage along the irradiation direction of the laser beam. A nozzle for laser processing, characterized in that disposed. According to claim 4,
The second nozzle extension part is coupled so that an upper end thereof surrounds at least a portion of a mount coupled to the processing head or the barrel part,
The second nozzle extension is provided with an inlet of the second flow path,
Characterized in that the inlet of the second passage is disposed at the same position as the lower end of the mount along the irradiation direction of the laser beam so as to be disposed at a position maximally spaced from the outlet of the second passage along the irradiation direction of the laser beam. nozzle for laser processing. According to claim 6,
a first airtight member disposed between the mount and the second nozzle extension;
The nozzle for laser processing, characterized in that it further comprises a second airtight member disposed between the mount and the barrel part. According to claim 4,
The second nozzle and the second nozzle extension is a nozzle for laser processing, characterized in that made of a single body. According to claim 1,
The second nozzle further comprises a water pressure sensor for measuring the water depth so that the supply pressure of the shield gas supplied to the second passage can be adjusted according to the water depth.

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