Laser processing apparatus and method for adjusting focal point position of laser using the same

Abstract

A laser processing apparatus (100) includes a laser oscillator that generates laser light (LB), a laser head (60) that irradiates the laser light (LB) toward a workpiece, and a manipulator (40) that mounts the laser head (60). The manipulator (40) includes a robot arm (41), a distal shaft (J6) that is rotatable about an axis (RA) and is provided at a distal end of the robot arm (41), and a connecting member (50) that connects the distal shaft (J6) and the laser head (60). The connecting member (50) includes a gauge mounting portion (51a) that is configured to mount a gauge (80) in a detachable manner. The gauge (80) includes a reference point that corresponds to a focal point position of the laser light (LB).

Description

TECHNICAL FIELD

[0001] The present application relates to a laser processing apparatus and a focal point position adjustment method of laser using the same. BACKGROUND

[0002] Conventionally, a technique of performing laser processing while moving a laser head using a robot is widely known. In this case, in order to perform desired processing, it is necessary to match the focal point position of actual laser emitted from the laser head with the focal point position of laser set by the robot or a control section thereof.

[0003] In Patent Literature 1, a laser processing apparatus using an electric scanner is proposed. By adjusting the position of a condensing lens using a lens driving mechanism provided to the electric scanner, the focal point alignment in the optical axis direction of laser can be performed with good accuracy. In addition, the focal point position can be adjusted with good accuracy with respect to a direction orthogonal to the optical axis direction using a galvanometer mirror connected to a motor.

[0004] In addition, in Patent Literature 2, a method of performing the focal point alignment of laser using a jig provided with a slit and a pin hole is proposed.

[0005] PRIOR ART DOCUMENTS

[0006] PATENT LITERATURE

[0007] Patent Literature 1: Japanese Patent Application Publication No. 2019-093399

[0008] Patent Literature 2: Japanese Patent Application Publication No. 2020-104168 SUMMARY

[0009] PROBLEMS TO BE SOLVED BY THE INVENTION

[0010] However, the electric scanner disclosed in Patent Literature 1 is expensive. On the other hand, in a cheap laser processing apparatus not having the electric scanner, it is necessary to move the laser head itself to match the focal point position of actual laser with the focal point position set by the robot, or to measure the focal point position of actual laser to set the focal point position by the robot. However, this requires troublesome and complicated work, and costs.

[0011] In addition, in the method disclosed in Patent Literature 2, it is necessary to determine the arrangement of the slit and the pin hole with high accuracy for the focal point alignment of laser, but in fact, such work is difficult.

[0012] The present application is made in view of the above points, and aims to provide a laser processing apparatus capable of confirming the focal point position of laser with good accuracy by a simple and inexpensive structure, and a focal point position adjustment method of laser using the same.

[0013] Means for solving the problem

[0014] To achieve the above object, the laser processing apparatus of the present application is characterized by comprising at least: a laser oscillator which generates at least laser light; a laser head which irradiates the laser light toward a workpiece; and a multi-joint robot which is provided with the laser head, the multi-joint robot having at least: a robot arm; a tip shaft which is rotatable about a prescribed axis and is provided at a front end of the robot arm; and a connecting member which connects the tip shaft and the laser head, a measuring instrument mounting portion for detachably mounting a measuring instrument being provided at the connecting member, the measuring instrument having a reference point corresponding to a focal point position of the laser light.

[0015] The focal point position adjustment method of the laser light of the present application uses the laser processing apparatus, and is characterized by comprising at least: a first step of mounting the measuring instrument at the connecting member provided at the tip shaft; a second step of, after the first step, emitting guide laser light from the laser head; a third step of, during execution of the second step, determining whether or not a distance between an irradiation position of the guide laser light on the measuring instrument and the reference point is within a prescribed range, and if the determination result in the third step is negative, adjusting a position of the laser head relative to the tip shaft and returning to the first step, and repeatedly executing the series of steps until the determination result in the third step becomes positive.

[0016] Effects of the Invention

[0017] According to the present application, the focal point position of the laser light can be confirmed with good precision by a simple and inexpensive structure. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a schematic configuration view of the laser processing apparatus of the embodiment.

[0019] Figure 2 is an enlarged view of a main part of a manipulator.

[0020] Figure 3 is an exploded perspective view of a connecting member which connects a laser head and a tip shaft.

[0021] Figure 4A is a perspective view of a measuring instrument.

[0022] Figure 4B is an enlarged view of a part enclosed by a broken line in Figure 4A .

[0023] Figure 5 is a flowchart showing a focal point position adjustment sequence of the laser light.

[0024] Figure 6A This is a schematic diagram illustrating a situation where the distance between the laser beam's irradiation position and the measuring instrument's reference point exceeds a specified range.

[0025] Figure 6B This is a schematic diagram showing the sequence of position adjustments of the laser head relative to the end axis.

[0026] Figure 6C This is a schematic diagram showing the situation where the distance between the irradiation position of the guiding laser and the reference point of the measuring instrument is within a specified range.

[0027] Figure 7A It is a 3D view of other measuring instruments.

[0028] Figure 7B It is by Figure 7A An enlarged view of the area enclosed by the dotted line. Detailed Implementation

[0029] The embodiments of the present invention will now be described with reference to the accompanying drawings. It should be noted that the following description of preferred embodiments is merely illustrative and is not intended to limit the invention, its applications, or its uses.

[0030] (Implementation Method 1)

[0031] [Structure of laser processing equipment]

[0032] Figure 1 A schematic structural diagram of the laser processing apparatus according to this embodiment is shown. It should be noted that, in the following description, the travel direction of the laser LB within the optical unit 20 will sometimes be referred to as the X direction. Figure 1 The direction intersecting the X direction on the surface of the workpiece 200 shown is called the Y direction. Sometimes, the directions intersecting both the X and Y directions are called the Z direction. Additionally, in the manipulator 40... Figure 1 In the static posture shown, for the Z direction, the side where the laser head 60 is located is sometimes referred to as the upper or upper side, and the side where the workpiece 200 is located is sometimes referred to as the lower or lower side. Similarly, in the same state, for the X direction, the side where the manipulator 40 is located is sometimes referred to as the front or front side, and the side where the robotic arm 41 is located is sometimes referred to as the rear or rear side.

[0033] like Figure 1 As shown, the laser processing apparatus 100 includes a laser oscillator 10, an optical unit 20, a manipulator 40, an optical fiber 30, and a laser head 60. Additionally, the laser processing apparatus 100 includes a laser control unit 71, a manipulator control unit 72, and a teach pendant 73.

[0034] The laser oscillator 10 generates laser light LB and emits the laser light LB toward the optical unit 20. In the present embodiment, the laser light LB has a wavelength of 900 nm to 1000 nm and an output of 1 kW to 5 kW. However, the present application is not particularly limited thereto, and other values can be taken respectively. In addition, the laser oscillator 10 has other laser sources (not shown) and emits guide laser light GLB from the other laser sources. The guide laser light GLB has a wavelength of about 650 nm and an output of several mW to several tens of mW. The optical axis of the guide laser light GLB is substantially coincident with the optical axis of the laser light LB.

[0035] Note that, in the present application, "substantially coincident" or "substantially orthogonal" means that the comparison objects are coincident or orthogonal in a manner that includes machining tolerances and assembly tolerances of the components that constitute the laser processing device 100. This does not mean that the comparison objects are coincident or orthogonal in a strict sense.

[0036] The optical unit 20 has a condenser lens 22 and a shutter 23 in the inside of a housing 21. The condenser lens 22 condenses the laser light LB that is incident to the inside of the housing 21 and emits the laser light LB toward the optical fiber 30. The shutter 23 is provided so as to be movable between the inside and the outside of the optical path of the laser light LB and controls the incident state of the laser light LB toward the optical fiber 30 by opening and closing. Note that, in order to match the condensing position of the laser light LB with the incident end surface of the optical fiber 30, a condensing position adjustment mechanism (not shown) can be provided in the optical unit 20.

[0037] The manipulator 40 is a publicly known vertical six-axis robot having first to sixth joint axes J1 to J6. Note that, in the following description, the sixth joint axis J6 will sometimes be referred to as the distal end axis J6. The distal end axis J6 is provided at the front end of the arm 41. In addition, the distal end axis J6 is configured to be rotatable around a predetermined axis RA (see FIG. 2). Note that, the cable 42 accommodates a cooling hose (not shown) of the laser head 60, I / O lines (not shown) of a thermal control switch, and the like. Figure 1 、 2 ) Note that, the cable 42 accommodates a cooling hose (not shown) of the laser head 60, I / O lines (not shown) of a thermal control switch, and the like.

[0038] The optical fiber 30 is connected to the optical unit 20 and the laser head 60 and transmits the laser light LB that is incident from the optical unit 20 toward the laser head 60. Note that, although not shown, the optical fiber 30 has one or a plurality of cores that serve as waveguides of the laser light LB.

[0039] The laser head 60 is attached to the manipulator 40, specifically, to the distal shaft J6 through the connecting member 50. The laser head 60 irradiates the laser LB transmitted from the optical fiber 30 to the laser head 60 toward the workpiece 200, and performs laser processing on the workpiece 200. In addition, the laser head 60 has an optical system, such as a collimator lens and a condenser lens, not shown, inside, and condenses the surface of the workpiece 200 after converting the laser LB into parallel light.

[0040] The laser head 60 rotates in conjunction with the rotation of the distal shaft J6, and moves on a circumference corresponding to the length of the connecting member 50. Here, the positional relationship of the laser head 60, the distal shaft J6, and the connecting member 50 connecting them is set in such a manner that the focal point position of the laser LB emitted from the laser head 60 does not change by the rotation of the laser head 60. In other words, the positional relationship of the laser head 60, the distal shaft J6, and the connecting member 50 connecting them is set in such a manner that the focal point position of the laser LB is located on the axis of rotation of the distal shaft J6, that is, the axis RA. Thus, for example, in the case where the manipulator 40 is pivoted, the accuracy of the operation becomes good. That is, in the case where the workpiece 200 is laser-processed while the distal shaft J6 is rotated, the focal point position of the laser LB can be made to be constant, and the laser processing can be appropriately performed on the prescribed processing point.

[0041] The laser control section 71 is electrically connected to the laser oscillator 10, and controls the operation of the laser oscillator 10. In addition, the operation of a power source (not shown) connected to the laser oscillator 10 is controlled. Specifically, the laser oscillator 10 controls the output and oscillation time of the laser LB, and in addition, controls the timing of the start and stop of the oscillation of the laser LB and the guide laser GLB.

[0042] The manipulator control section 72 is electrically connected to the manipulator 40, and controls the operation of the manipulator 40. Specifically, the manipulator control section 72 controls the moving speed and moving amount of the laser head 60 connected to the manipulator 40 by controlling the rotation speed and rotation amount of the motors (not shown) connected to the first joint shaft J1 to the sixth joint shaft J6, respectively.

[0043] Note that the manipulator control section 72 controls the operation of the manipulator 40 based on a prepared operation program or parameters input from the teaching pendant 73. Note that the focal point position of the laser LB emitted from the laser head 60 is also set to be stored in the manipulator control section 72.

[0044] The teacher 73 is a device for storing a prescribed motion in the manipulator control section 72. The operator actually operates the manipulator 40 using the teacher 73, and stores various parameters, such as the rotation amount of the motor (not shown) connected to each of the first joint axis J1 to the sixth joint axis J6 from one teaching point to the next teaching point, and the like, in the manipulator control section 72. In addition, the manipulator 40 is caused to execute the motion stored in the manipulator control section 72 again, and the various parameters are finely corrected using the teacher 73 as necessary, and the various parameters are stored in the manipulator control section 72 again.

[0045] [Structure of manipulator and measuring instrument]

[0046] Figure 2 An enlarged view showing the main part of the manipulator, Figure 3 An exploded perspective view showing the connecting member connecting the laser head and the tip shaft. Figure 4A A perspective view showing the measuring instrument, Figure 4B An enlarged view of the part enclosed by the broken line of Figure 4A It should be noted that, Figure 2 A state before the measuring instrument 80 is mounted to the measuring instrument mounting section 51a is shown.

[0047] As shown in Figure 2 , the laser head 60 is mounted to the tip shaft J6 by the connecting member 50. In addition, as shown in Figure 3 , the connecting member 50 is composed of a first member 51 to a third member 53.

[0048] As shown in Figure 2 , the measuring instrument mounting section 51a is provided in the first member 51. The measuring instrument mounting section 51a is composed of a flat surface 51a2 of the first member 51 and a through-hole 51al that penetrates the first member 51 in the Z direction in Figure 2 . The above axis RA that is the rotational axis of the tip shaft J6 is an imaginary line that passes through the center of the through-hole 51al and is substantially orthogonal to the flat surface 51a2. In addition, as shown in Figure 2 , the measuring instrument 80 is mounted to the lower part of the through-hole 51al. In addition, the tip shaft J6 is mounted to the upper part of the through-hole 51al.

[0049] As shown in Figure 3 , the first member 51 has a plurality of first bolt holes 51b in a manner that encloses the through-hole 51al. The first bolts 54a are respectively inserted into the plurality of first bolt holes 51b. By fastening and joining the first bolts 54a, the first member 51 is mounted and fixed to the tip shaft J6.

[0050] The second member 52 has a recess 52a at the rear in the X direction. In addition, the second member 52 has a mounting portion 52e at the front in the X direction. The mounting portion 52e is quadrangular in shape when viewed from the front.

[0051] In addition, the first positioning hole 52b to the third positioning hole 52d are formed in the second member 52. The first positioning hole 52b is formed in the side surface of the second member 52, and two are formed at intervals in the Z direction. In addition, the inner diameter of the first positioning hole 52b is longer in the X direction than in the Z direction. The second positioning hole 52c is formed in the upper surface of the second member 52, and two are formed at intervals in the Y direction. In addition, the inner diameter of the second positioning hole 52c is longer in the X direction than in the Y direction. The third positioning hole 52d is formed in each of the four corners of the mounting portion 52e of the second member 52. In addition, the inner diameter of the third positioning hole 52d is longer in the Y direction than in the Z direction.

[0052] In the first member 51, the second bolt hole 51c and the third bolt hole 51d are provided at positions corresponding to the first positioning hole 52b and the second positioning hole 52c of the second member 52, respectively. The third member 53 is a plate-shaped member that is mounted to the side surface of the laser head 60. In the third member 53, the fourth bolt hole 53a is provided at a position corresponding to the third positioning hole 52d of the second member 52. In addition, the third member 53 has a plurality of fifth bolt holes 53b. The fifth bolt 54e is inserted into each of the plurality of fifth bolt holes 53b. By fastening and joining the fifth bolt 54e, the third member 53 is mounted and fixed to the laser head 60.

[0053] In the state in which the connection member 50 is assembled, the front portion of the first member 51 is accommodated in the recess 52a of the second member 52. In addition, the mounting portion 52e of the second member 52 abuts against the surface of the third member 53. In addition, the second bolt 54b is inserted into the first positioning hole 52b and the second bolt hole 51c, and the third bolt 54c is inserted into the second positioning hole 52c and the third bolt hole 51d. By fastening and joining the second bolt 54b and the third bolt 54c, respectively, the second member 52 is mounted to the first member 51. In addition, the fourth bolt 54d is inserted into the third positioning hole 52d and the fourth bolt hole 53a. By fastening and joining the fourth bolt 54d, the second member 52 is mounted to the third member 53.

[0054] The positional relationship between the first component 51 and the second component 52 is adjusted by the positions of the second bolt 54b and the third bolt 54c, which are respectively inserted into the first positioning hole 52b and the second positioning hole 52c. For example, if it is desired to shift the second component 52 forward relative to the first component 51 in the X direction, the second bolt 54b and the third bolt 54c are inserted into the first positioning hole 52b and the second positioning hole 52c at positions forward of the center in the X direction, respectively, and the second bolt 54b and the third bolt 54c are tightened to install the second component 52 onto the first component 51. Similarly, the positional relationship between the second component 52 and the third component 53 is adjusted by the position of the fourth bolt 54d, which is inserted into the third positioning hole 52d. For example, if it is desired to shift the second component 52 relative to the third component 53 in the Y direction, the fourth bolt 54d is inserted into the third positioning hole 52d at a position forward of the center in the Y direction, and the fourth bolt 54d is tightened to install the second component 52 onto the third component 53.

[0055] The measuring instrument 80 is a component used to confirm the focal position of the laser LB. For example... Figure 4A As shown, the measuring instrument 80 consists of a head 81 and a leg 82 extending linearly from the head 81. The head 81 consists of a protrusion 81a and a flange 81b surrounding the protrusion 81a. With the protrusion 81a received in the through hole 51a1 and the upper surface of the flange 81b abutting against the flat surface 51a2 of the first component 51, the flange 81b is threadedly fastened to the first component 51. Furthermore, by loosening the threaded fastening between the flange 81b and the first component 51, the measuring instrument 80 can be easily detached from the measuring instrument mounting portion 51a. That is, the measuring instrument 80 is mounted to the measuring instrument mounting portion 51a in a detachable manner.

[0056] like Figure 4B As shown, the leg 82 is a cylindrical member with a notch 83 in the middle portion along the Z direction. A center line 84 extending along the Z direction is formed in the center of the notch 83. It should be noted that in this embodiment, the center line 84 is a drawing line formed by scribing on the surface of the notch 83. With the measuring instrument 80 mounted on the measuring instrument mounting part 51a, the center line 84 of the notch 83 is approximately aligned with the axis RA. In this state, the measuring instrument 80 is positioned at the intersection with the optical path of the laser LB emitted from the laser head 60. The intersection of the lower end of the notch 83 in the Z direction and the center line 84 of the notch 83 becomes a reference point 85 corresponding to the focal position of the laser LB.

[0057] As described later, the measuring instrument 80 is attached to the attachment member 50, and the adjustment work of the focal position of the laser LB is performed. In addition, at the time of the usual laser processing, the measuring instrument 80 is of course detached from the measuring instrument attachment portion 51a.

[0058] [Sequence of adjustment of focal position of laser]

[0059] Figure 5 A flowchart showing the sequence of adjustment of the focal position of the laser is shown. Figure 6A A schematic view showing a case where the distance between the irradiation position of the guide laser and the reference point of the measuring instrument exceeds a prescribed range. Figure 6B A schematic view showing the sequence of adjustment of the position of the laser head with respect to the tip shaft. Figure 6C A schematic view showing a case where the distance between the irradiation position of the guide laser and the reference point of the measuring instrument is within a prescribed range.

[0060] In a state where the laser LB is emitted from the laser head 60, the manipulator 40 moves the laser head 60 in a manner passing through a trajectory decided in advance, whereby the desired laser processing can be performed on the workpiece 200. At this time, the focal position of the laser LB needs to be located on the surface of the workpiece 200 as the processing target or in the vicinity thereof.

[0061] However, in a case where the laser head 60 is detached from the manipulator 40 by maintenance or the like and attached again, the position of the laser head 60 with respect to the tip shaft J6 of the manipulator 40 is sometimes shifted. Due to this position shift, the focal position of the laser LB is sometimes shifted from the position set by the manipulator control section 72. When such a situation occurs, there is a possibility that the width of the weld bead, the diameter of the hole at the time of hole cutting, or the cutting width at the time of cutting, or the like deviates from the desired range, and processing failure occurs.

[0062] Therefore, in a case where the laser head 60 is detached from the manipulator 40, or in a case where other maintenance or the like is performed, it is necessary to confirm whether the focal position of the laser LB is located at the desired position. In a case where the focal position of the laser LB is shifted from the position set by the manipulator control section 72, adjustment work for restoration needs to be performed. Note that, after maintenance of the laser processing apparatus 100, in a case where the parameters of the action program of the manipulator 40 are again set by the teach pendant 73, confirmation of the focal position of the laser LB needs to be performed as shown in the present embodiment, and adjustment is performed as necessary.

[0063] In the present embodiment, by attaching the measuring instrument 80 to the measuring instrument attachment portion 51a, and confirming the irradiation position of the guide laser GLB with respect to the reference point 85, confirmation of the focal position of the laser LB and adjustment of the focal position as necessary are performed. Hereinafter, the Figure 5 and Figure 6A-6C are further described.

[0064] like Figure 5 As shown, when confirming the focal position of the laser LB, the measuring instrument 80 is mounted on the measuring instrument mounting section 51a of the first component 51 (step S1 (first step)). In this state, a guiding laser GLB is generated using the laser oscillator 10, and the guiding laser GLB is transmitted to the laser head 60 via the optical unit 20 and the optical fiber 30. The transmitted guiding laser GLB is emitted towards the outside of the laser head 60. The optical path of the guiding laser GLB is approximately the same as the optical path of the laser LB. Therefore, it can be said that the measuring instrument 80 is positioned at a position where it intersects with the optical path of the guiding laser GLB emitted from the laser head 60. That is, the guiding laser GLB is irradiated onto the measuring instrument 80 (step S2 (second step)).

[0065] In addition, when the focal position of the laser LB is at the position set by the manipulator control unit 72, the guide laser GLB is irradiated onto the reference point 85 of the measuring instrument 80.

[0066] Therefore, during the execution of step S2, it is determined whether the guiding laser GLB is illuminating the reference point 85. More specifically, it is determined whether the distance between the illuminating position of the guiding laser GLB on the measuring instrument 80 and the reference point 85 is within a specified range (step S3 (third step)).

[0067] The judgment result in the third step is positive, that is, the distance between the irradiation position of the guiding laser GLB on the measuring instrument 80 and the reference point 85 is within the specified range (refer to...). Figure 6C If the laser LB is located at the position set by the manipulator control unit 72, the operation is terminated.

[0068] On the other hand, if the result of the third step is negative, that is, if the distance between the irradiation position of the guiding laser GLB on the measuring instrument 80 and the reference point 85 exceeds the specified range, then... Figure 6A In the case shown, it is determined that the focal position of the laser LB has deviated from the position set by the manipulator control unit 72. In this case, the focal position of the laser LB is corrected by adjusting the position of the laser head 60 relative to the end shaft J6 (step S4 (fourth step)). Specifically, the measuring instrument 80 is removed from the end shaft J6. Furthermore, the positional relationship of the first component 51 to the third component 53 included in the connecting component 50 is adjusted to correct the focal position of the laser LB. Specifically, as described above, the insertion positions of the second bolt 54b to the fourth bolt 54d at the first positioning hole 52b to the third positioning hole 52d of the second component 52 are adjusted, such as... Figure 6B As shown, the positional relationship between the first component 51 and the third component 53 is adjusted, thereby adjusting the position of the laser head 60 relative to the end axis J6.

[0069] After the step S4 is ended, the step S1 is returned, and the series of steps are repeatedly executed until the result of the third step becomes affirmative.

[0070] Note that the distance between the irradiation position of the guide laser GLB on the gauge 80 and the reference point 85 is of course preferably zero. In the case where chromatic aberration exists in the optical system inside the condenser lens 22 and the laser head 60, in the case where the optical path of the guide laser GLB and the optical path of the laser LB are offset, and the like, the distance between the irradiation position of the guide laser GLB on the gauge 80 and the reference point 85 is not zero, and the aforementioned prescribed range can be a finite value. Note that this prescribed range is appropriately decided in accordance with the laser processing method, the specifications required of the laser processing device 100, and the like.

[0071] [Effects, etc.]

[0072] As explained above, the laser processing device 100 of the present embodiment at least has the laser oscillator 10 that generates at least the laser LB, the laser head 60 that irradiates the laser LB toward the workpiece 200, and the manipulator (multi-joint robot) 40 that mounts the laser head 60.

[0073] The manipulator 40 at least has the arm 41, the end shaft J6 that is capable of rotating around the prescribed axis RA and is provided to the front end of the arm 41, and the connecting member 50 that connects the end shaft J6 and the laser head 60.

[0074] The connecting member 50 is provided with the gauge mounting portion 51a for mounting the gauge 80 in a detachable manner. The gauge 80 has the reference point 85 that corresponds to the focal point position of the laser LB.

[0075] According to the present embodiment, the focal point position of the laser LB can be confirmed with good precision by a simple and inexpensive structure. In addition, in the case where the optical axis of the laser LB fluctuates, for example, at the time of replacing the laser oscillator 10, the optical fiber 30, and the laser head 60, it is not necessary to correct the action program of the manipulator 40.

[0076] The connecting member 50 has the first member 51 to the third member 53, and the first member 51 is mounted to the end shaft J6. In addition, the gauge mounting portion 51a is provided to the first member 51.

[0077] The laser processing device 100 is configured so that the focal point position of the laser LB can be adjusted by adjusting the positional relationship between the first member 51 to the third member 53 included in the connecting member 50.

[0078] According to the present embodiment, the focal point position of the laser LB can be adjusted with good precision by a simple and inexpensive structure.

[0079] With the measuring instrument 80 mounted on the measuring instrument mounting section 51a, the center line 84 extending along the length direction of the measuring instrument 80 is approximately aligned with the rotation axis RA of the end shaft J6. Furthermore, a reference point 85 is provided on the center line 84.

[0080] Therefore, the focal position of the laser LB can be determined easily and inexpensively.

[0081] The measuring instrument 80 is a cylindrical component with a notch 83 in the middle part along the length direction, i.e., the Z direction. The intersection of the lower end of the notch 83 and the center line 84 of the notch 83 extending along the Z direction is the reference point 85.

[0082] Therefore, when the guiding laser GLB is irradiated onto the measuring instrument 80, it is possible to reliably determine whether the guiding laser GLB is irradiating the reference point 85.

[0083] Typically, when determining whether the guiding laser GLB is illuminating the reference point 85, the operator wearing protective gear makes a visual judgment or uses a camera to measure the distance between the illuminating position of the guiding laser GLB at the measuring instrument 80 and the reference point 85.

[0084] When reference point 85 is displayed on a plane, for example, when reference point 85 is displayed as an image on a plane parallel to axis RA, it may be difficult to determine whether the guide laser GLB is illuminating reference point 85, depending on the intensity of the guide laser GLB and the sensitivity of the camera.

[0085] On the other hand, when the aforementioned intersection point is used as the reference point 85, when the guide laser GLB is irradiated toward the reference point 85, the guide laser GLB scatters, and the reflected light expands. When the guide laser GLB is offset from the reference point 85 and irradiates the portion of the notch 83 or the leg 82 located below the notch 83, the scattering of the guide laser GLB decreases, and consequently, the expansion of the reflected light decreases.

[0086] In this way, by also evaluating the extent of the spread of the reflected light from the guiding laser GLB, it is possible to reliably and with good accuracy determine whether the guiding laser GLB is illuminating the reference point 85.

[0087] The laser LB focal position adjustment method of this embodiment includes step S1 (first step) of mounting a measuring instrument 80 on the connecting member 50 mounted on the end shaft J6, and step S2 (second step) of emitting a guiding laser GLB from the laser head 60 after step S1.

[0088] It also includes step S3 (third step) during the execution of step S2, which determines whether the distance between the irradiation position of the guiding laser GLB on the measuring instrument 80 and the reference point 85 is within a specified range.

[0089] If the result of the determination in step S3 is negative, the position of the laser head 60 with respect to the terminal shaft J6 is adjusted (step S4), and the series of steps are repeated until the result of the determination in step S3 becomes positive.

[0090] According to the present embodiment, the focal point position of the laser LB can be adjusted easily and inexpensively.

[0091] In addition, by adjusting the positional relationship among the first member 51 to the third member 53 included in the connecting member 50, the focal point position of the laser LB can be adjusted with good accuracy.

[0092] In addition, in the case where the optical axis of the laser LB varies, for example, at the time of replacing the laser oscillator 10, the optical fiber 30, or the laser head 60, it is not necessary to correct the operation program of the manipulator 40, and shortening of the maintenance work time of the laser processing device 100 can be achieved. In addition, an increase in maintenance cost can be suppressed.

[0093] (Other Embodiments)

[0094] In the embodiment, the case where the connecting member 50 is composed of the first member 51 to the third member 53 is described, but it is not particularly limited thereto. For example, the third member 53 can be omitted, and the second member 52 can be directly attached to the laser head 60. In addition, the connecting member 50 can have other members than the first member 51 to the third member 53. Figure 4A In addition, the case where the measuring instrument 80 is as shown in Figs. 8A and 8B is described, but the shape of the measuring instrument 80 is not particularly limited thereto. For example, as shown in Figs. 9A and 9B, the leg portion 86 of the measuring instrument 80 can also be prismatic. In addition, the reference point 87 can also be a cross shape formed on the side surface of the leg portion 86. Note that the reference point 87 is preferably recessed inward from the side surface of the leg portion 86 or protrudes outward as shown in Figs. 10A and 10B. Thereby, in the case where the guide laser GLB is irradiated toward the reference point 87, it is possible to reliably and with good accuracy determine whether the guide laser GLB is irradiated on the reference point 87 by also evaluating the spread of the reflected light of the guide laser GLB. Figure 4B In addition, the shape of the reference point is not limited to the example shown in Figs. 8A and 8B. For example, a plurality of recesses or protrusions can be provided in the measuring instrument 80, and the intersection of the plurality of recesses or protrusions can be used as the reference point 87. Figure 7A In addition, the reference point 87 is preferably recessed inward from the side surface of the leg portion 86 or protrudes outward as shown in Figs. 10A and 10B. Thereby, in the case where the guide laser GLB is irradiated toward the reference point 87, it is possible to reliably and with good accuracy determine whether the guide laser GLB is irradiated on the reference point 87 by also evaluating the spread of the reflected light of the guide laser GLB. Figure 7B In addition, the shape of the reference point is not limited to the example shown in Figs. 8A and 8B. For example, a plurality of recesses or protrusions can be provided in the measuring instrument 80, and the intersection of the plurality of recesses or protrusions can be used as the reference point 87.

[0095] Figure 4B In addition, the shape of the reference point is not limited to the example shown in Figs. 8A and 8B. For example, a plurality of recesses or protrusions can be provided in the measuring instrument 80, and the intersection of the plurality of recesses or protrusions can be used as the reference point 87. Figure 7B In addition, in the embodiment, the case where the connecting member 50 is composed of the first member 51 to the third member 53 is described, but it is not particularly limited thereto. For example, the third member 53 can be omitted, and the second member 52 can be directly attached to the laser head 60. In addition, the connecting member 50 can have other members than the first member 51 to the third member 53.

[0096] In addition, in the embodiment, the case where the connecting member 50 is composed of the first member 51 to the third member 53 is described, but it is not particularly limited thereto. For example, the third member 53 can be omitted, and the second member 52 can be directly attached to the laser head 60. In addition, the connecting member 50 can have other members than the first member 51 to the third member 53.

[0097] ​In addition, in the embodiment, an example in which the robot is shown as the manipulator 40 having six joint axes J1 to J6, but is not particularly limited thereto. For example, it can also be a multi-joint robot in which the manipulator 40 has three or more joint axes. In this case, the tip axis is also capable of rotating around a prescribed axis and is provided at the front end of the robot arm 41.

[0098] In addition, in the embodiment, an example in which the laser oscillator 10 has a laser source that generates the guide laser GLB is shown, but the laser source can also be provided separately from the laser oscillator 10. The optical axis of the guide laser GLB incident on the optical fiber 30 can be substantially coincident with the optical axis of the laser LB.

[0099] Industrial applicability

[0100] The laser processing apparatus of the present application is useful because it can confirm the focal position of the laser with good precision by a simple and inexpensive structure.

[0101] Explanation of reference numerals

[0102] 10 laser oscillator

[0103] 20 optical unit

[0104] 21 housing

[0105] 22 condenser lens

[0106] 23 shutter

[0107] 30 optical fiber

[0108] 40 manipulator

[0109] 41 robot arm

[0110] 42 cable

[0111] 50 connecting member

[0112] 51 first member

[0113] 51a gauge mounting portion

[0114] 51a2 flat surface

[0115] 51a1 through hole

[0116] 51b first bolt hole

[0117] 51c second bolt hole

[0118] 51d third bolt hole

[0119] 52 second member

[0120] 52b first positioning hole

[0121] 52c Second positioning hole

[0122] 52d Third positioning hole

[0123] 52e Mounting portion

[0124] 53 Third member

[0125] 53a Fourth bolt hole

[0126] 53b Fifth bolt hole

[0127] 54a to 54e First bolt to fifth bolt

[0128] 60 Laser head

[0129] 71 Laser control section

[0130] 72 Manipulator control section

[0131] 73 Demonstrator

[0132] 80 Measuring instrument

[0133] 81 Head portion

[0134] 81a Convex portion

[0135] 81b Flange

[0136] 82, 86 Leg portion

[0137] 83 Notch portion

[0138] 84 Center line

[0139] 85, 87 Reference point

[0140] 100 Laser processing apparatus

[0141] 200 Workpiece

[0142] J1 to J5 First joint axis to fifth joint axis

[0143] J6 Sixth joint axis (end axis)

[0144] LB Laser light

[0145] GLB Guide laser light

Claims

1. A laser processing apparatus characterized by comprising: a laser oscillator that generates at least laser light; a laser head that irradiates the laser light toward a workpiece; and a multi-joint robot that is provided with the laser head, the multi-joint robot including: a robot arm; a tip shaft that is rotatable about a prescribed axis and is provided at a front end of the robot arm; and a connecting member that connects the tip shaft and the laser head, a gauge mounting portion for detachably mounting a gauge is provided to the connecting member, the gauge is composed of a head portion and a leg portion that extends linearly from the head portion, the leg portion has a reference point that corresponds to a focal point position of the laser light, the connecting member includes at least a first member and a second member, the first member is mounted to the tip shaft, the gauge mounting portion is provided to the first member, the laser processing apparatus is configured to be able to adjust the focal point position of the laser light by adjusting a positional relationship between the members included in the connecting member.

2. The laser processing apparatus according to claim 1, characterized in that: a plurality of recesses or protrusions are provided to the gauge, and an intersection of the plurality of recesses or protrusions is the reference point.

3. The laser processing apparatus according to claim 1 or 2, characterized in that: in a state in which the gauge is mounted to the gauge mounting portion, a center line of the gauge that extends in a length direction thereof is substantially coincident with the axis, and the reference point is provided on the center line.

4. A focal point position adjustment method for a laser light using the laser processing apparatus according to claim 3, characterized by comprising: a first step of mounting the gauge to the connecting member mounted to the tip shaft; a second step of, after the first step, emitting a guide laser light from the laser head; and a third step of, during execution of the second step, determining whether or not a distance between an irradiation position of the guide laser light on the gauge and the reference point is within a prescribed range, and if the determination result in the third step is negative, adjusting a position of the laser head with respect to the tip shaft and returning to the first step, and repeating the series of steps until the determination result in the third step becomes positive. ​ ​ ​

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