Laser processing device

Abstract

To switch laser welding and laser cutting, using one laser head.SOLUTION: A laser head 10 has an incident part 20, a first emission part 21, a second emission part 22, and an optical path switching part 12. The optical path switching part 12 selectively switches the optical path of a laser beam LB to a first optical path L1 and a second optical path L2. The focal distance of a second condensing lens 16 arranged on the second optical path L2 is shorter than the focal distance of a first condensing lens 14 arranged on the first optical path L1.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a laser processing device. [Background technology]

[0002] Patent Document 1 discloses a laser processing system that includes a beam path switching unit that switches the optical path of laser light (laser beam) emitted from a laser oscillator, a plurality of process fibers into which the laser light is incident, and a plurality of laser heads (processing heads) that are respectively connected to the tips of the plurality of process fibers.

[0003] In the invention of Patent Document 1, the laser head through which the laser light is guided is switched by a beam path switching unit, and laser processing such as welding and cutting is performed on the workpiece from various angles and positions by the movement of the articulated robot. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2018-153815 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the conventional inventions, it is necessary to use a plurality of laser heads to perform laser welding or laser cutting, which increases the size of the entire apparatus and increases the capital investment costs.

[0006] The present invention has been made in view of the above points, and an object of the present invention is to enable laser welding and laser cutting to be performed by switching between them using a single laser head. [Means for solving the problem]

[0007] A first invention is a laser processing apparatus comprising a laser oscillator that emits laser light, and a laser head that emits the laser light emitted by the laser oscillator toward a workpiece, wherein the laser head has an incident section into which the laser light emitted by the laser oscillator is incident, a first exit section that emits the laser light, a second exit section that is provided at a position different from the first exit section and emits the laser light, and an optical path switching section that selectively switches the optical path of the laser light between a first optical path from the incident section to the first exit section and a second optical path from the incident section to the second exit section, and is provided with a first focusing lens that is arranged upstream of the first exit section in the emission direction on the first optical path, and a second focusing lens that is arranged upstream of the second exit section in the emission direction on the second optical path and has a focal length shorter than that of the first focusing lens.

[0008] In the first aspect of the present invention, the optical path of the laser light is selectively switched between the first optical path and the second optical path, thereby allowing laser welding and laser cutting to be performed by switching between them using a single laser head.

[0009] Specifically, when performing laser welding, it is necessary to increase the distance from the emission end of the first emission part to the workpiece and increase the diameter of the focused spot, while when performing laser cutting, it is necessary to decrease the distance from the emission end of the second emission part to the workpiece and decrease the diameter of the focused spot.

[0010] Here, in the present invention, the focal length of the second condenser lens arranged on the second optical path is set to be shorter than the focal length of the first condenser lens arranged on the first optical path.

[0011] Thus, by switching the optical path of the laser light, the laser light can be emitted from the first emission portion to perform laser welding, and the laser light can be emitted from the second emission portion to perform laser cutting.

[0012] A second aspect of the present invention is the laser processing apparatus of the first aspect of the present invention, further comprising an opening / closing mechanism that opens and closes the laser light exit port of the first emission unit.

[0013] In the second invention, during laser welding, the opening / closing mechanism opens the opening of the first emission part, allowing the laser beam to be emitted from the first emission part, while during laser cutting, the opening / closing mechanism closes the opening of the first emission part, allowing the laser beam to be emitted from the second emission part.

[0014] This makes it possible to prevent spatters and fumes generated from the workpiece from entering the inside of the laser head through the emission port of the first emission part when laser cutting is performed by bringing the laser head close to the workpiece.

[0015] A third invention is the laser processing apparatus of the second invention, wherein the opening and closing mechanism has an opening and closing cover that can move along a direction intersecting the emission direction of the laser light to open and close the emission port.

[0016] In the third aspect of the present invention, the opening of the first emission part can be opened and closed by moving the opening / closing cover in a direction intersecting the emission direction of the laser light.

[0017] A fourth invention is a laser processing apparatus according to the second invention, wherein the opening and closing mechanism has a central axis extending in a direction intersecting the emission direction of the laser light, and an opening and closing lid that can rotate around the central axis to open and close the emission port.

[0018] In the fourth aspect of the present invention, the opening of the first emission part can be opened and closed by rotating the openable / closable cover around the central axis.

[0019] A fifth invention is the laser processing device of any one of the first to fourth inventions, wherein an emission end of the first emission portion is located upstream of an emission end of the second emission portion in the emission direction of the laser light.

[0020] In the fifth aspect of the present invention, when laser cutting is performed by bringing the laser head close to the workpiece, it is possible to prevent the emission end of the first emission part from interfering with the workpiece. [Effects of the Invention]

[0021] According to the present invention, laser welding and laser cutting can be performed by switching between them using one laser head. [Brief explanation of the drawings]

[0022] [Figure 1] 1 is a diagram showing the configuration of a laser processing device according to a first embodiment. [Figure 2] FIG. 2 is a side cross-sectional view showing the configuration of the laser head. [Figure 3] FIG. 2 is a perspective view showing the configuration of an optical path switching unit. [Figure 4] FIG. 4 is a side cross-sectional view showing a state in which laser light is emitted from a second emission portion. [Figure 5] FIG. 10 is a side cross-sectional view showing the configuration of a laser head according to a second embodiment. [Figure 6] FIG. 4 is a side cross-sectional view showing a state in which laser light is emitted from a second emission portion. [Figure 7] FIG. 10 is a perspective view showing the configuration of an opening and closing mechanism according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0023] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the following description of the preferred embodiments is merely exemplary in nature and is not intended to limit the present invention, its applications, or its uses.

[0024] First Embodiment As shown in FIG. 1, the laser processing apparatus 1 includes a laser oscillator 2, a transmission fiber 3, a gas supply unit 4, a gas pipe 5, a robot 6, a control unit 7, and a laser head 10.

[0025] The laser oscillator 2 oscillates a laser beam LB based on a command from the control unit 7. An incident end of a transmission fiber 3 is connected to the laser oscillator 2. A connector 3a is provided at the output end of the transmission fiber 3. The connector 3a is connected to an incident unit 20 (described later) of the laser head 10. The laser beam LB is transmitted from the laser oscillator 2 to the laser head 10 via the transmission fiber 3.

[0026] The gas supply unit 4 supplies high-pressure gas used during laser cutting. One end of a gas pipe 5 is connected to the gas supply unit 4. The other end of the gas pipe 5 is connected to a pipe connection unit 41 (described later) of the laser head 10 (see FIG. 2).

[0027] The robot 6 has a plurality of arms. The laser head 10 is attached to the tip of the arm of the robot 6. The robot 6 moves the laser head 10 relative to the workpiece W based on a command from the control unit 7.

[0028] The control unit 7 controls the operations of the robot 6 and the laser head 10. The control unit 7 has a function of controlling the speed at which the laser head 10 is moved by the robot 6, as well as the start and stop of output of the laser light LB, the output intensity of the laser light LB, and the like.

[0029] 2, the laser head 10 emits a laser beam LB oscillated by a laser oscillator 2 toward a workpiece W. The laser head 10 has an incident portion 20, a first emitting portion 21, and a second emitting portion 22. Inside the laser head 10, a first optical path L1 and a second optical path L2 are provided.

[0030] The incident part 20 is provided at the incident end of the laser head 10. The incident part 20 is formed in a cylindrical shape. A connector 3a of the transmission fiber 3 is connected to the incident part 20. The laser light LB oscillated by the laser oscillator 2 is incident on the incident part 20 via the transmission fiber 3.

[0031] The first emission section 21 is provided at the emission end of the laser head 10. The first emission section 21 is formed in a cylindrical shape. The second emission section 22 is provided at a position different from the first emission section 21 at the emission end of the laser head 10. The second emission section 22 is formed in a cylindrical shape that tapers toward the emission end.

[0032] The first optical path L1 is the optical path of the laser beam LB traveling from the incident portion 20 toward the first exit portion 21. The second optical path L2 is the optical path of the laser beam LB traveling from the incident portion 20 toward the second exit portion 22 (see FIG. 4).

[0033] The first emitting section 21 emits the laser light LB that has passed through the first optical path L1 toward the workpiece W. The second emitting section 22 emits the laser light LB that has passed through the second optical path L2 toward the workpiece W (see FIG. 4).

[0034] The laser head 10 accommodates a collimating lens 11, an optical path switching unit 12, a reflecting mirror 13, a first condenser lens 14, a first protective glass 15, a second condenser lens 16, and a second protective glass 17 inside.

[0035] The collimator lens 11 collimates the laser light LB that has entered the incident portion 20 of the laser head 10 via the transmission fiber 3 .

[0036] The optical path switching unit 12 selectively switches the optical path of the laser light LB collimated by the collimator lens 11 between a first optical path L1 (see FIG. 2) and a second optical path L2 (see FIG. 4).

[0037] The reflecting mirror 13 is disposed in the middle of the second optical path L2. Specifically, the reflecting mirror 13 is disposed at a position where it reflects the laser light LB reflected by a switching mirror 12a of the optical path switching unit 12, which will be described later, toward the second condenser lens 16.

[0038] The first condenser lens 14 is disposed on the first optical path L1 upstream in the emission direction of the first emission part 21. The first protective glass 15 is disposed downstream in the emission direction of the first condenser lens 14. The first protective glass 15 prevents foreign matter such as fumes and spatters from entering the inside of the laser head 10 through the first emission part 21.

[0039] The second condenser lens 16 is disposed on the second optical path L2 upstream in the emission direction of the second emission part 22. The second protective glass 17 is disposed downstream in the emission direction of the second condenser lens 16. The second protective glass 17 prevents foreign matter such as fumes and spatters from entering the inside of the laser head 10 through the second emission part 22.

[0040] 3, the optical path switching unit 12 includes a switching mirror 12a and a rotary drive unit 12b. The switching mirror 12a is attached to the rotary drive unit 12b. The rotary drive unit 12b is configured, for example, with a stepping motor or the like that is capable of adjusting the angle. The switching mirror 12a is rotated by the rotary drive unit 12b.

[0041] The optical path switching unit 12 selectively switches the posture of the switching mirror 12a between a first position (see FIG. 2) where the switching mirror 12a is retracted from the first optical path L1 and a second position (see FIG. 4) where the switching mirror 12a is positioned on the first optical path L1.

[0042] At the first position, the switching mirror 12a is retracted from the first optical path L1. As a result, the laser light LB collimated by the collimator lens 11 passes through the first optical path L1. The laser light LB passing through the first optical path L1 is condensed by the first condenser lens 14 and then emitted to the workpiece W.

[0043] 4, at the second position, the switching mirror 12a is disposed on the first optical path L1. As a result, the laser beam LB collimated by the collimator lens 11 is reflected by the switching mirror 12a and passes through the second optical path L2. The laser beam LB passing through the second optical path L2 is reflected by the reflecting mirror 13, condensed by the second condenser lens 16, and then emitted toward the workpiece W.

[0044] Here, the focal length of the second condenser lens 16 is shorter than that of the first condenser lens 14. As a result, by selectively switching the optical path of the laser light LB between the first optical path L1 and the second optical path L2, it is possible to switch between laser welding and laser cutting using one laser head 10.

[0045] Specifically, when performing laser welding, it is necessary to increase the distance WD1 from the emission end of the first emission part 21 to the workpiece W and increase the diameter of the focused spot. On the other hand, when performing laser cutting, it is necessary to decrease the distance WD2 from the emission end of the second emission part 22 to the workpiece W and decrease the diameter of the focused spot.

[0046] Therefore, in this embodiment, the focal length of the second condenser lens 16 arranged on the second optical path L2 is set to be shorter than the focal length of the first condenser lens 14 arranged on the first optical path L1.

[0047] For example, consider the case where the core diameter of the transmission fiber 3 is φ100 μm and the focal length of the collimator lens 11 is 100 mm. Here, when the focal length of the first focusing lens 14 is 500 mm, the focused spot diameter is approximately φ500 μm, which is suitable for laser welding. In addition, the distance WD1 from the output end of the first output part 21 to the processing point of the workpiece W can be ensured to be 400 mm or more.

[0048] On the other hand, when the focal length of the second condenser lens 16 is 150 mm, the diameter of the condensed spot is 150 μm. In addition, in the laser cutting process, the distance WD2 from the emission end of the second emission part 22 to the processing point of the workpiece W is within a range of 10 mm at most.

[0049] As a result, by switching the optical path of the laser beam LB, the laser beam LB can be emitted from the first emission portion 21 to perform laser welding, and the laser beam LB can be emitted from the second emission portion 22 to perform laser cutting.

[0050] 2, it is assumed that two plate-shaped workpieces W are overlapped and laser welded, and the example shown in FIG. 4, it is assumed that one plate-shaped workpiece W is laser cut.

[0051] 2, the first emission unit 21 is provided with an opening / closing mechanism 30. The opening / closing mechanism 30 has an opening / closing lid 31. The opening / closing lid 31 is movable by a drive mechanism (not shown) in a direction intersecting the emission direction of the laser light LB.

[0052] Specifically, a housing portion 26 recessed in the radial direction is provided on the inner circumferential surface of the emission port 25 of the first emission portion 21. The opening / closing lid 31 is housed in the housing portion 26 so as to be removably inserted therein.

[0053] The second emission part 22 is provided with a gas nozzle 40 and a piping connection part 41. The gas nozzle 40 is attached to the emission end of the second emission part 22. The gas nozzle 40 injects high-pressure gas onto the workpiece W during laser cutting.

[0054] The pipe connection part 41 is attached so as to communicate with the space between the gas nozzle 40 and the second protective glass 17 in the second emission part 22. The gas pipe 5 is connected to the pipe connection part 41. Thus, high-pressure gas is supplied from the gas supply part 4 through the gas pipe 5 to the inside of the second emission part 22.

[0055] 2, during laser welding, laser light LB passes through a first optical path L1. The opening / closing mechanism 30 accommodates the opening / closing lid 31 in the accommodation portion 26 so as to open the exit port 25 of the first emission portion 21. The laser light LB is emitted from the first emission portion 21 toward the workpiece W.

[0056] As shown in Fig. 4, during laser cutting, the laser beam LB passes through the second optical path L2. The opening / closing mechanism 30 moves the opening / closing lid 31 from the storage section 26 onto the first optical path L1 so as to close the exit port 25 of the first emission section 21. The laser beam LB is emitted from the second emission section 22 toward the workpiece W. At this time, high-pressure gas is sprayed from the gas nozzle 40 toward the workpiece W.

[0057] This prevents spatter and fumes generated from the workpiece W from entering the interior of the laser head 10 through the exit port 25 of the first emission section 21 when laser cutting is performed by bringing the laser head 10 close to the workpiece W.

[0058] During laser cutting, high-pressure gas is sprayed from the gas nozzle 40 of the second emission part 22, which prevents spatter and the like from entering the inside of the laser head 10 from the second emission part 22. Therefore, there is no need to provide an opening / closing mechanism 30 on the second emission part 22 side.

[0059] Here, the emission end of the first emission part 21 is located upstream in the emission direction of the laser light LB from the emission end of the second emission part 22. With this configuration, it is possible to prevent the emission end of the first emission part 21 from interfering with the workpiece W when laser cutting is performed by bringing the laser head 10 close to the workpiece W.

[0060] Second Embodiment Hereinafter, the same parts as those in the first embodiment will be denoted by the same reference numerals, and only the differences will be described.

[0061] 5 and 6, the first emission section 21 is provided with an opening / closing mechanism 30. The opening / closing mechanism 30 has an opening / closing lid 31 and a central axis 32. The central axis 32 extends in a direction intersecting the emission direction of the laser light LB. The opening / closing lid 31 can rotate about the central axis 32 by a drive mechanism (not shown) to open and close the emission opening 25.

[0062] 5, during laser welding, laser light LB passes through a first optical path L1. The opening / closing mechanism 30 rotates the opening / closing lid 31 about a central axis 32 to move it away from the first optical path L1 so as to open the exit port 25 of the first emission part 21. The laser light LB is emitted from the first emission part 21 toward the workpiece W.

[0063] As shown in Fig. 6, during laser cutting, the laser beam LB passes through the second optical path L2. The opening / closing mechanism 30 rotates the open / close lid 31 around the central axis 32 to move it onto the first optical path L1 so as to close the emission port 25 of the first emission part 21. The laser beam LB is emitted from the second emission part 22 toward the workpiece W. At this time, high-pressure gas is sprayed from the gas nozzle 40 toward the workpiece W.

[0064] In this way, by rotating the openable / closable cover 31 around the central axis 32, the exit port 25 of the first exit part 21 can be opened and closed.

[0065] Other Embodiments The above embodiment may be configured as follows.

[0066] In this embodiment, the second focusing lens 16 and the gas nozzle 40 are fixedly disposed at preset positions in the laser head 10, but the present invention is not limited to this. For example, the height distance between the spot position of the laser beam LB and the emission end of the gas nozzle 40 may be adjustable. Furthermore, the positional relationship between the optical axis of the laser beam LB and the center position of the gas nozzle 40 may be adjustable.

[0067] In this embodiment, the distance WD1 from the emission end of the first emission part 21 to the workpiece W is ensured to be sufficiently long (for example, 500 mm), thereby preventing spatter and the like from entering through the emission opening 25 of the first emission part 21. Here, for example, if it is necessary to perform laser welding with the distance WD1 short (for example, 200 mm or less), an air blow unit (not shown) may be installed and used to blow away spatter and the like.

[0068] In this embodiment, as an example of the opening / closing mechanism 30, a configuration in which one opening / closing lid 31 is used to close the exit port 25 of the first emission part 21 has been described, but the present invention is not limited to this configuration.

[0069] For example, as shown in FIG. 7, the opening / closing cover 31 of the opening / closing mechanism 30 may be configured to be able to adjust the opening area of ​​the light outlet 25, like the aperture mechanism of a camera.

[0070] The opening / closing lid 31 may be divided into two pieces, and each piece may be moved forward and backward from the left and right in Fig. 2 to open and close the outlet 25. The opening / closing lid 31 may also be divided into multiple pieces, stacked in the thickness direction and stored in the storage section 26, and the pieces may be moved forward and backward sequentially from the right in Fig. 2 to open and close the outlet 25.

[0071] In this embodiment, the optical path switching unit 12 is configured to include the switching mirror 12a and the rotary drive unit 12b, but may also be configured to use, for example, a galvanometer mirror. [Industrial Applicability]

[0072] As described above, the present invention has the highly practical effect of being able to switch between laser welding and laser cutting using a single laser head, and is therefore extremely useful and has high industrial applicability. [Explanation of symbols]

[0073] 1. Laser processing equipment 2 Laser oscillator 10 Laser Head 12 Optical path switching unit 14 First condenser lens 16 Second focusing lens 20 Input part 21 First exit section 22 Second exit section 25 Exit 30 Opening and closing mechanism 31 Opening and closing lid 32 Center axis L1 1st optical path L2 2nd optical path LB laser light double work

Claims

1. A laser processing apparatus including a laser oscillator that oscillates a laser beam and a laser head that emits the laser beam oscillated by the laser oscillator toward a workpiece, The laser head includes: an incident portion into which the laser light oscillated by the laser oscillator is incident; a first emission unit that emits the laser light; a second emission section provided at a position different from the first emission section and configured to emit the laser light; an optical path switching unit that selectively switches the optical path of the laser light between a first optical path from the incident unit toward the first exit unit and a second optical path from the incident unit toward the second exit unit, a first condenser lens disposed on the first optical path upstream of the first exit portion in an exit direction; a second condenser lens that is disposed on the second optical path upstream of the second exit portion in the emission direction and has a focal length shorter than that of the first condenser lens; Laser processing equipment.

2. 2. The laser processing apparatus according to claim 1, an opening / closing mechanism for opening and closing the laser beam exit port of the first exit unit; Laser processing equipment.

3. 3. The laser processing apparatus according to claim 2, The opening / closing mechanism has an opening / closing cover that can move in a direction intersecting the emission direction of the laser light to open and close the emission opening. Laser processing equipment.

4. 3. The laser processing apparatus according to claim 2, The opening / closing mechanism has a central axis extending in a direction intersecting the emission direction of the laser light, and an opening / closing cover that can rotate around the central axis to open and close the emission port. Laser processing equipment.

5. 5. The laser processing apparatus according to claim 1, The emission end of the first emission section is located upstream of the emission end of the second emission section in the emission direction of the laser light. Laser processing equipment.

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