JP4151889B2 - Torch for laser processing - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a laser processing torch operated mainly by hand.
[0002]
[Prior art]
FIG. 4 shows an example of a conventional laser processing torch. The laser processing torch 101 includes a flexible torch lead 102 in which a fiber optic cable for guiding laser light, a hose for assist gas supply (not shown) and the like are accommodated, and a cylindrical shape attached to the tip of the torch lead 102. The handle portion 103 and the nozzle portion 104 provided at the tip of the handle portion 103 are provided. Then, the handle portion 103 is gripped in the manner of gripping the pen, the nozzle portion 104 at the tip of the handle portion 103 is brought into contact with the processing surface 106 of the work 105, and laser light and assist gas are emitted from the tip of the nozzle portion 104. Then, processing such as welding or fusing can be performed on the processing surface 106.
[0003]
[Patent Document 1]
Registered Utility Model No. 301567 (Claim 3)
[Patent Document 2]
JP-A-9-57481
[Problems to be solved by the invention]
By the way, such a laser processing torch 101 does not emit laser light unless the tip nozzle portion 104 is in contact with the processing surface 106 of the workpiece 105 or pressed with a predetermined pressure for reasons of safety or the like. It is like that. That is, when a contact pressure is applied to the conduction or torch by bringing the nozzle portion 104 into contact with or pressed against the processing surface 106 of the workpiece 105, a mechanical switch that forms a safety circuit is activated, and laser light is emitted from the laser oscillator. The light is emitted (see Patent Document 1 and Patent Document 2).
[0005]
Therefore, when machining, the nozzle portion 104 must be slid on the machining surface 106 while the nozzle portion 104 is always in contact with the machining surface 106 of the workpiece 105 with a predetermined pressure (pressing the torch). Therefore, the nozzle portion 104 is worn early due to sliding friction with the workpiece 105, or the nozzle portion 104 is caught on the workpiece 105 during processing, and the nozzle portion 104 cannot slide on the processing surface 106 as expected. Problems arise. Further, in order to continuously perform the process of sliding while pressing the nozzle portion 104 against the processing surface 106 of the workpiece 105 in this way, the material of the nozzle portion 104 that is a contact portion with the workpiece 105 is made of carbon or the like. Must be limited to specific materials with good slipperiness.
[0006]
The present invention has been made in view of the above circumstances, and while ensuring the safety of laser processing, it is possible to increase the degree of freedom of material selection of the nozzle part and improve the durability of the nozzle part. An object of the present invention is to provide a laser processing torch that can be used.
[0007]
[Means for Solving the Problems]
In order to solve the above-described problems, a laser processing torch according to the present invention is provided with a handle portion having a laser emitting portion for emitting laser light therein, and provided at an end of the handle portion and supplied from an assist gas supply source. An ON state in which laser light is guided to the laser emitting portion in a laser processing torch having an assist gas emitted from the tip and a nozzle portion that emits laser light emitted from the laser emitting portion from the tip A switch that is switched to an OFF state in which light guide of the laser beam to the laser emitting unit is blocked, a nozzle unit that is disposed so as to surround a tip of the nozzle unit from which the assist gas is discharged, and the nozzle unit and has a pressure receiving surface for receiving the pressure of the assist gas that is reflected by the work piece is released from the tip, the assist acting on the pressure receiving surface Actuated by the gas pressure of the scan, characterized by comprising a gas pressure acting elements turning ON said switch.
[0008]
Therefore, according to the above configuration, at the time of processing, it is not necessary to slide the nozzle portion on the processing surface while keeping the nozzle portion in contact with the processing surface of the workpiece material with a predetermined pressure (while pushing the torch). Therefore, it is possible to avoid a situation in which the nozzle portion is worn due to sliding friction with the material to be processed or the nozzle portion is caught on the material to be processed during processing, and the material of the nozzle portion is made of carbon or the like. It is not necessary to limit to a specific material with good slipperiness. That is, in the laser processing torch of the present invention, while ensuring the safety of laser processing, it is possible to increase the degree of freedom in selecting the material of the nozzle part, and to improve the durability of the nozzle part, Processability can be obtained.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
As shown in FIG. 1, a laser processing torch 1 according to this embodiment includes a cylindrical handle portion 4 and a nozzle portion that is detachably attached to the tip of the handle portion 4 and emits laser light L, for example. 16. A laser emitting portion 22 for emitting laser light (YAG laser) L is fixedly supported in the handle portion 4, and an optical fiber extends from the laser emitting portion 22 toward the proximal end side (hand side). 2 extends. The optical fiber 2 is accommodated in a flexible torch lead together with, for example, an assist gas supply hose and a cooling water supply / discharge hose, and is connected to a laser oscillator.
[0010]
A plurality of lenses 8 that make the laser light L emitted from the laser emitting portion 22 focal light are disposed in the distal end portion of the handle portion 4. Further, a protective glass 20 that protects the lens 8 from sputtering during processing is disposed in front of the lens 8.
[0011]
A switch box 6 is juxtaposed on the side of the handle portion 4. The switch box 6 is provided with an emission button 10 for opening a shutter in the laser oscillator to oscillate YAG laser light. Further, an assist gas supply tube 30 connected to an assist gas supply source (not shown) extends from the switch box 6. In this case, a gas flow path is formed in the handle portion 4 so that assist gas (a gas that stabilizes and induces processing) supplied through the assist gas supply tube 30 is discharged through the tip of the nozzle portion 16.
[0012]
Further, the switch box 6 has a built-in stroke switch 12 having a switch portion 12a that is pressed and turned ON / OFF by a gas pressure operation holder 14 described later (converted into an ON / OFF electric signal by a stroke). . The stroke switch 12 forms, for example, a laser control circuit together with a control unit (not shown) that controls the operation of the laser oscillator and the emission button 10, and the stroke switch 12 is turned on when the emission button 10 is pressed. Then, the laser control circuit is closed, and the laser oscillator is operated (laser light is emitted) by the control unit.
[0013]
A gas pressure operating holder (gas pressure operating body) 14 is attached to the tip of the handle portion 4 so as to surround the nozzle portion 16 from the outside. The gas pressure operation holder 14 has a switch pressing portion 14a that can face the switch portion 12a of the stroke switch 12 and press the switch portion 12a. Further, the gas pressure operation holder 14 is always urged toward the distal end side (direction in which the switch pressing portion 14a is separated from the switch portion 12a) by a spring 18 inserted between the handle portion 4 and the gas pressure operation holder 14. Further, a pressure receiving surface 14 b that receives the pressure of the assist gas that is ejected from the nozzle portion 16 and reflected from the workpiece W is formed at the tip of the gas pressure operation holder 14. Note that the spring 18 is set to have elasticity so that when the pressure receiving surface 14b receives a predetermined gas pressure, the spring 18 is compressed to allow the switch pressing portion 14a to be pressed by the switch pressing portion 12a.
[0014]
Next, the case where the workpiece W is processed using the laser processing torch 1 having the above-described configuration will be described.
FIG. 2 shows a state in which the nozzle portion 16 is not opposed to the workpiece W. In this state, since there is no shielding object in front of the nozzle part 16, the assist gas flowing in the handle part 4 is released into the atmosphere through the inside of the nozzle part 16 (the assist gas released into the atmosphere is illustrated). (Indicated with an arrow). Accordingly, no gas pressure acts on the pressure receiving portion 14b of the gas pressure operating holder 14. That is, the gas pressure operation holder 14 is urged (pressed down) by the spring 18 to the front end side, and the switch pressing portion 14a does not press the switch portion 12a of the stroke switch 12 (not turned ON). Therefore, even when the emission button 10 is pressed, the laser control circuit is not closed, and the laser beam L is not emitted from the tip of the nozzle portion 16.
[0015]
FIG. 3 shows a state in which the nozzle portion 16 faces the workpiece W. In this state, the assist gas ejected from the nozzle portion 16 is reflected by the workpiece W and acts on the pressure receiving surface 14b of the gas pressure operation holder 14. Accordingly, when the nozzle portion 16 is brought close to the machining surface of the workpiece W to a predetermined distance with the emission button 10 turned on, the gas pressure operating holder 14 causes the gas pressure (preliminarily applied) to the pressure receiving surface 14b. The set pressure) is pushed up against the biasing force of the spring 18, and the switch pressing portion 14a presses (turns on) the switch portion 12a of the stroke switch 12. Accordingly, the laser control circuit is closed, the laser oscillator is operated by the control unit, and the laser beam L is emitted from the tip of the nozzle unit 16.
[0016]
As described above, the laser processing torch 1 of the present embodiment is in the ON state in which the laser beam is guided to the laser emitting unit 22 and the OFF state in which the laser beam is not guided to the laser emitting unit 22. The stroke switch 12 to be switched, and the pressure receiving surface 14b that receives the pressure of the gas discharged from the tip of the nozzle portion 16 and reflected by the workpiece (workpiece material) W, are operated by the gas pressure acting on the pressure receiving surface 14b. And a gas pressure operation holder 14 for turning on the stroke switch 12. Therefore, at the time of processing, it is not necessary to slide the nozzle portion 16 on the processing surface while keeping the nozzle portion 16 in contact with the processing surface of the workpiece W at a predetermined pressure (while pushing the torch). Therefore, it is possible to avoid a situation in which the nozzle portion 16 is worn due to sliding friction with the workpiece W, or the nozzle portion 16 is caught on the workpiece W during processing, and the material of the nozzle portion 16 is made of carbon or the like. It is not necessary to limit to a specific material with good slipperiness. That is, according to the laser processing torch 1 of the present embodiment, while ensuring the safety of laser processing, the degree of freedom in selecting the material of the nozzle portion 16 can be increased, and the durability of the nozzle portion 16 is improved. And excellent workability can be obtained.
[0017]
Needless to say, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention. For example, in the above-described embodiment, the stroke switch 12 is a mechanical contact switch. However, the operation of the gas pressure on the pressure receiving surface 14b can be performed in a non-contact manner using a photoelectric sensor, a proximity sensor, a capacitance sensor, or the like. It may be able to be detected.
[0018]
【The invention's effect】
As described above, according to the laser processing torch of the present invention, while ensuring the safety of laser processing, the degree of freedom in selecting the material of the nozzle portion can be increased, and the durability of the nozzle portion is improved. be able to.
[Brief description of the drawings]
1A and 1B are views showing a laser processing torch according to an embodiment of the present invention, in which FIG. 1A is a cross-sectional view, and FIG.
2A is an enlarged cross-sectional view of a main part of the laser processing torch of FIG. 1 showing a state where a nozzle portion is not opposed to a workpiece, and FIG. 2B is a view in the direction of arrow A in FIG.
3 is an enlarged cross-sectional view of a main part of the laser processing torch of FIG. 1 showing a state in which a nozzle portion faces a workpiece.
FIG. 4 is a schematic view of a conventional laser processing required torch.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Laser processing torch 4 Handle part 12 Stroke switch 14 Gas pressure operation holder (gas pressure operation body)
14b Pressure receiving surface 22 Laser emitting part 16 Nozzle part 30 Assist gas supply tube (gas supply means)

Claims (1)

A handle portion having a laser emitting portion for emitting laser light therein;
For laser processing, comprising: a nozzle portion that is provided at the tip of the handle portion and that emits assist gas supplied from an assist gas supply source from the tip, and that emits laser light emitted from the laser emitting portion from the tip In the torch,
A switch that is switched between an ON state in which laser light is guided to the laser emitting unit and an OFF state in which light guiding of the laser light to the laser emitting unit is blocked;
The assist gas is disposed so as to surround the tip of the nozzle part from which the assist gas is discharged, and has a pressure receiving surface that receives the pressure of the assist gas that is discharged from the tip of the nozzle part and reflected by the work material. A gas pressure operating body that is operated by the gas pressure of the assist gas acting on the pressure receiving surface to turn on the switch;
A laser processing torch characterized by comprising:

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