JP2004148360A - Laser beam machining head, and laser beam machining system using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent deposition of scattered matters from a work generated during the laser beam machining on a laser collector caused by the inflow of the scattered matters inside a head in a laser beam machining head and a laser beam machining system in which the work is irradiated with laser beams and machined thereby. <P>SOLUTION: In the laser beam machining head 11 used in the laser beam machining system, gas introduced from a gas inlet 22 is diffused to a head base body 12 having the gas inlet 22 via a carrying passage 35 formed in a gas carriage unit 32 provided on a nozzle body 13 communicating and joined with the gas inlet 22, and directly blown against a condenser lens 14 from a peripheral edge, and the gas blown against the condenser lens 14 is discharged to the work side. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a laser processing head and a laser processing system when processing is performed by irradiating a workpiece with a laser beam.
[0002]
[Prior art]
In recent years, processing using a laser beam has been performed, and the scope of application has been expanded to include objects such as metal, plastic, and paper. Laser processing is mainly performed by heat, and spatter and smoke are generated during processing. And when this spatter | spatter and smoke penetrate | invade in a laser processing head, it will contaminate a lens and protective glass, and will cause the fall of a laser output. In addition, the thermal processing using laser light causes a burning phenomenon in which the processed portion is expanded. Therefore, a technique for injecting a cooling gas into the laser processing head to reduce the burning and preventing the inflow of spatter and smoke by letting the gas flow out from the head tip is disclosed in the following patent documents and the like. .
[0003]
[Patent Document 1]
JP-A-6-198485 [Patent Document 2]
JP-A-9-1374 [Patent Document 3]
Japanese Patent Laid-Open No. 11-226770
FIG. 6 is an explanatory diagram of a conventional laser processing head. The laser processing head 101 shown in FIG. 6 (A) is a conceptual diagram of the basic invention of Patent Document 2 described above, and is the base of Patent Documents 1 and 3. That is, the gas supply unit 103 is provided on the side of the cylindrical nozzle 102 (on the workpiece side from the lens described later), and the lens 104 is held above the gas supply unit 103 inside. During laser processing, the laser beam 106 is condensed on the workpiece 105 by the lens 104, and a shield gas 107 is injected into the nozzle 102 from the gas supply unit 103. At this time, the injected shield gas 107 is sprayed from the tip of the head to the processed portion of the workpiece 105 so that the shield gas 107 enters a shielded state inside the nozzle 102 to prevent the inflow of spatter and smoke. It is what.
[0005]
In Patent Documents 1 and 3, the nozzle 102 is composed of an inner cylinder (inner wall) and an outer cylinder (outer wall) and the shielding gas (assist gas) is injected into the inner cylinder (inner wall). In addition to blowing out from the tip and injecting cooling gas into the outer cylinder (outer wall) to blow out from the tip, the shield gas (assist gas) 107 is used to prevent inflow of spatter and smoke, and cooling gas This is intended to reduce burning.
[0006]
[Problems to be solved by the invention]
However, when the shielding gas (assist gas) 107 injected into the nozzle 102 is discharged, a situation in which spatter or smoke actually flows from the tip of the nozzle 102 occurs. This is because the shield gas (assist gas) 107 is injected into the nozzle 102 in a horizontal state, so that the flow velocity inside becomes non-uniform, and as shown in FIG. This is presumably due to inhalation of scattered matter 105A such as spatter and smoke. In Patent Document 3, it appears that the assist gas is uniformly injected into the inside (inner wall) of the nozzle 102 and the internal flow velocity seems to be uniform. However, the assist gas is injected into the nozzle 102 in a horizontal state. It is considered that the internal flow rate becomes non-uniform and the tornado state 107A is generated, and the scattered matter 104A is sucked.
[0007]
Accordingly, the present invention has been made in view of the above problems, and a laser processing head and a laser processing system that prevent adhesion of scattered objects from a workpiece generated during laser processing to the laser condensing portion due to inflow into the head. The purpose is to provide.
[0008]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, in the invention of claim 1, a laser processing head for applying a predetermined processing by irradiating a workpiece with a generated laser beam, formed of a cylindrical member, A head base having a gas inlet to which a gas is supplied; and a head base that is held in the head base, collects the generated laser light, and converges and irradiates the processed portion of the workpiece. A laser condensing part and an internal space for irradiating the workpiece with laser light from the laser condensing part are formed and joined to the head substrate in communication with the gas inlet. A gas transport unit that disperses the gas introduced from the gas introduction port and forms a transport path for spraying directly from the periphery to the laser condensing unit, and the gas sprayed to the laser condensing unit The workpiece side A structure including a nozzle body for discharging the.
[0009]
The invention of claim 2 is configured such that “the laser condensing portion is a condensing lens or a protective member provided on the condensing lens and the workpiece side”.
[0010]
According to a third aspect of the present invention, the laser processing head according to the first or second aspect, laser generating means for generating laser light to be irradiated to the workpiece from the laser processing head, the head substrate, and the nozzle body Gas supply means for supplying a predetermined gas to the gas inlet of the laser processing head to which is bonded.
[0011]
As described above, in the laser processing head used in the laser processing system, the nozzle body that is joined to the head base having the gas introduction port in communication with the gas introduction port is provided in the provided gas transport unit. The gas introduced from the gas introduction port is dispersed in the formed conveyance path and blown directly to the laser condensing part from the periphery, and the gas blown to the laser condensing part is discharged to the workpiece side. That is, the introduced gas is dispersed and sprayed directly onto the laser condensing unit, so that the flow velocity of the dispersed gas inside the nozzle body is made uniform, and a tornado state in which scattered matter is sucked in when discharged on the workpiece side. It is possible to prevent the occurrence, and it is possible to prevent the scattered matter from the workpiece generated during the laser processing from adhering to the laser condensing part due to the inflow into the head.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In the present embodiment, the object to be laser processed is described as paper, but the present invention can also be applied to metals, plastics, films, and the like. In the present embodiment, the gas introduced into the head is described as air. However, even gas that is normally used in laser processing, such as oxygen gas or nitrogen gas, can be applied.
[0013]
FIG. 1 shows a configuration diagram of a laser processing head according to the present invention. FIG. 1A is a cross-sectional view of a main part of a laser processing head, FIG. 1B is an explanatory view of a head base constituting the head, and FIG. 1C is an explanatory view of a nozzle body constituting the head. 1A to 1C, a laser processing head 11 is for irradiating an object to be processed (paper) with a generated laser beam to perform a predetermined processing. It is configured to include a condenser lens 14 which is a laser condensing unit held inside the body 13 and the head base 12. The condensing lens 14 condenses the generated laser light and converges it on the processed portion of the workpiece (paper) to irradiate it.
[0014]
As shown in FIG. 1B, the head base 12 is formed of a cylindrical member, and a step-shaped holding portion 21 (fixing member is not shown) that holds the condenser lens 14 at a predetermined position. At the same time, a gas introduction port 22 to which a predetermined gas (here, referred to as air) is supplied is formed below (portion joined to the nozzle body).
[0015]
As shown in FIG. 1C, the nozzle body 13 includes an inverted conical nozzle tip portion 31 and a gas transport portion 32, and a condenser lens extending from the gas transport portion 32 to the nozzle tip portion 31. The nozzle inner wall part 33 which forms the internal space for irradiating the to-be-processed object (paper) to the laser beam from 14 is provided. The gas transport unit 32 is, for example, cylindrical, and a predetermined number of protrusions 34 are integrally formed on the lens side at a predetermined interval (preferably at equal intervals). The outer peripheral portions of the protrusions 34 are in contact with the inner wall of the nozzle base 12 on the gas inlet 22 side. Further, a space region formed between the nozzle base 12 and the gas transport part 32 when the nozzle base 12 is joined serves as a gas transport path 35, and a joint part with the nozzle tip 31 serves as a base joint surface 36.
[0016]
The nozzle body 13 shown in FIG. 1 (C) is fitted and joined by the nozzle base 12 shown in FIG. The gas inlet 22 of the nozzle base 12 and the gas transport path 35 are communicated with each other, and the condenser lens 14 is held on the hold part 21 of the nozzle base 12 above the gas transport part 32. That is, the gas conveyance path 35 is arranged such that the air introduced from the gas introduction port 22 is dispersed in the space region between the projecting portions 34 from the introduction region below the gas conveyance portion 32 to the condenser lens 14 side positioned above. It is guided and sprayed directly to the condenser lens 14 from the periphery. The air blown to the condenser lens 14 is discharged to the workpiece side through the nozzle inner wall portion 33.
[0017]
FIG. 2 shows a cross-sectional configuration diagram of a laser processing system in which the laser processing head of FIG. 1 is used, and FIG. 3 shows an explanatory diagram of supply air in the laser processing system of FIG. In FIG. 2, a laser processing system 41 includes at least the laser processing head 11 shown in FIG. 1, a laser generator 42, and a compressor 43 that is a gas supply means, and performs predetermined processing on a sheet 45 that is a workpiece. . Such processing on the paper 45 includes formation of a through hole, half cut, and the like, for example, formation of perforation lines by cutting, cutting, information formation, etc., and formation of information that is difficult to see by half cut.
[0018]
The laser generation unit 42 generates laser light to irradiate the paper 45 with respect to the laser processing head 11, and examples of common lasers include a CO ₂ laser and a YAG laser. The laser beam 51 generated by the laser generator 42 is condensed by the condenser lens 14, converged on the processed portion of the paper 45, and irradiated from the nozzle tip 31. The compressor 43 generates compressed air 52, and the air 52 is supplied into the laser processing head 11 from a supply nozzle 44 attached to the gas inlet 22 of the laser processing head 11.
[0019]
That is, as shown in FIG. 3A, the air 52 introduced from the gas introduction port 22 from the compressor 43 through the supply nozzle 44 is in the gas conveyance path 35 formed by the nozzle base 12 and the gas conveyance unit 32. It is guided circumferentially in the lower space region, and is distributed and guided upward along the space region (conveyance path) formed between the protrusions 34 from here. The air 52 is directly blown from the peripheral edge to the condenser lens 14 (not shown in FIG. 3A) held in the holding portion 21 formed in the nozzle base 12.
[0020]
The air 52 blown to the condenser lens 14 forms an air curtain 52A on the surface of the condenser lens 14 as shown in FIG. It is sprayed on the processed part. At this time, in the nozzle inner wall portion 33, the air 52 is blown onto the surface of the condenser lens 14 at a substantially uniform flow rate to form the air curtain 52 </ b> A, and then is blown down to the tip of the nozzle. Therefore, there is almost no non-uniformity in the flow velocity, and the tornado state that sucks in the scattered matter such as spatter and smoke generated during processing as before is not generated.
[0021]
In this way, the air 52 introduced from the gas inlet 22 is dispersed and sprayed directly onto the condenser lens 14 to equalize the flow velocity of the dispersed air in the nozzle inner wall portion 33, and the air on the surface of the condenser lens 14. By forming the curtain 52A and discharging it to the paper 45 side, it is possible to prevent the occurrence of a tornado state in which scattered matter such as spatter and smoke generated at the time of processing is sucked. The scattered matter does not flow into the head and can be prevented from adhering to the condenser lens 14.
[0022]
Next, FIG. 4 shows a cross-sectional configuration diagram of a laser processing system in which another laser processing head according to the present invention is used. A laser processing system 41 shown in FIG. 4 is configured by a condensing lens 14 and a protective glass 61 as a protective member to constitute a laser condensing unit. That is, the protective glass 61 is held by the hold portion 21 formed inside the nozzle base 12, and the condenser lens 14 is held by the hold portion 62 formed thereabove. Therefore, the condensing lens 14 is protected from the nozzle body 13 by the protective glass 61.
[0023]
Also in the laser processing head 11 as described above, in the conventional shield gas (assist gas) supply format, the scattered glass such as spatter and smoke is sucked to contaminate the protective glass, leading to a decrease in laser output. However, when the air 52 is directly blown onto the protective glass 61 as in the present invention, the air curtain 52A is formed on the surface of the protective glass 61 and discharged to the side of the paper 45 as described above. The generation of a tornado state that inhales scattered matter such as spatter and smoke is prevented, so that the scattered matter generated from the paper 45 during laser processing does not flow into the head and adheres to the condenser lens 14. It can be prevented.
[0024]
Next, FIG. 5 shows a configuration diagram of another laser processing head according to the present invention. The laser processing head 11 shown in FIG. 5 has substantially the same diameter as the inner circle of the holding part 21 in the nozzle base 12 in place of the protruding part 34 formed in the gas conveying part 32 in the nozzle body 13 shown in FIG. The protrusions 71 are integrally formed, and a predetermined number (preferably equally spaced) air holes 72 penetrating in the vertical direction in the drawing are formed. The air holes 72 serve as a gas transport path 35 that blows air directly onto the condenser lens 14 (or the protective glass 61).
[0025]
That is, the condensing lens 14 (or the protective glass 61) positioned above by dispersing the air introduced from the gas introduction port 22 through the air holes 72 (conveyance path 35) from the introduction region below the gas conveyance unit 32. It is guided to the side and sprayed directly to the condenser lens 14 (or protective glass 61) from the periphery. Then, the air blown onto the condenser lens 14 (or the protective glass 61) passes through the nozzle inner wall portion 33 and is discharged to the paper 45 side.
[0026]
Also by configuring the nozzle body 13 in the laser processing head 11 as described above, the air 52 introduced from the gas inlet 22 is dispersed and sprayed directly onto the condenser lens 14 (or the protective glass 61) in the same manner as described above. The air curtain 52A can be formed on the surface of the condensing lens 14 (or the protective glass 61) by equalizing the flow velocity of the dispersed air in the nozzle inner wall portion 33. It is possible to prevent the generation of a tornado state in which scattered matter such as spatter and smoke generated during processing is sucked in. Therefore, the scattered matter generated from the paper 45 during laser processing is not flown into the head and is directed to the condenser lens 14. Can be prevented.
[0027]
【The invention's effect】
As described above, in the laser processing head used in the laser processing system, the gas transport portion provided with the nozzle body that is joined to the head base in which the gas introduction port is formed in communication with the gas introduction port. By dispersing the gas introduced from the gas introduction port in the conveyance path formed in the above and causing the laser condensing part to be directly blown from the peripheral edge, and discharging the gas blown to the laser condensing part to the workpiece side, The flow velocity of the dispersed gas inside the nozzle body is made uniform, and it is possible to prevent the scattered matter from the workpiece generated during laser processing from adhering to the laser condensing part due to the inflow into the head. .
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a laser processing head according to the present invention.
FIG. 2 is a cross-sectional configuration diagram of a laser processing system in which the laser processing head of FIG. 1 is used.
FIG. 3 is an explanatory diagram of supply air in the laser processing system of FIG. 2;
FIG. 4 is a cross-sectional configuration diagram of a laser processing system in which another laser processing head according to the present invention is used.
FIG. 5 is a configuration diagram of another laser processing head according to the present invention.
FIG. 6 is an explanatory diagram of a conventional laser processing head.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 Laser processing head 12 Head base body 13 Nozzle body 14 Condensing lens 22 Gas inlet 31 Nozzle tip part 32 Gas conveyance part 33 Nozzle inner wall part 34,71 Projection part 35 Gas conveyance path 41 Laser processing system 42 Laser irradiation part 43 Compressor 45 Paper 51 Laser light 52 Air 61 Protective glass 72 Air hole

Claims (3)

A laser processing head for performing predetermined processing by irradiating a workpiece with a generated laser beam,
A head base formed of a cylindrical member and having a gas inlet to which a predetermined gas is supplied;
A laser condensing unit that is held in the head substrate and condenses the generated laser light to converge and irradiate the processed part of the workpiece;
An internal space for irradiating the workpiece with laser light from the laser condensing unit is formed and joined to the head base in communication with the gas inlet, and the gas inlet A gas transport unit that disperses the introduced gas and forms a transport path for spraying directly from the periphery to the laser condensing unit, and discharges the gas sprayed to the laser condensing unit to the workpiece side A nozzle body,
A laser processing head characterized by comprising: The laser processing head according to claim 1, wherein the laser condensing unit is a condensing lens or a protective member provided on the condensing lens and the workpiece side. The laser processing head according to claim 1 or 2,
Laser generating means for generating laser light to be irradiated to the workpiece from the laser processing head;
A gas supply means for supplying a predetermined gas to a gas introduction port of the laser processing head in which the head base and the nozzle body are joined;
A laser processing system comprising:

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