Laser processing device

Abstract

A laser processing apparatus according to the present disclosure includes: an oscillator configured to oscillate a laser beam; an irradiation optical system that guides a laser beam to a member to be processed; a measurement optical system that guides processing light from the measurement region, the processing light including any one of heat radiation light, plasma light, and reflected light radiated from the member by irradiation of the laser beam; a sensor that measures the intensity of the processing light guided by the measurement optical system; a moving device that relatively moves an irradiation point formed by the laser beam from the starting point along the scanning path with respect to the member; an adjustment device that shifts the position of the measurement region with respect to the position of the irradiation point; and a control unit that controls the adjustment device such that the center of the measurement region is positioned closer to the starting point side than the center of the irradiation point along the scanning path.

Description

Technical Field

[0001] The present disclosure relates to a laser processing device. Background Art

[0002] Laser processing devices, in addition to processing components, also assess the processing status. When a component is irradiated with a laser beam, it melts, forming a molten zone. This molten zone emits light, including thermal radiation, plasma light, and laser reflection light. By measuring the peak intensity of this light or the integrated value of the light intensity (luminous energy), the processing status can be evaluated.

[0003] For example, in Patent Document 1, a laser beam is irradiated from a head portion, and light emitted from a molten portion is measured using a measuring portion attached to the head portion to monitor the processing state.

[0004] In Patent Document 2, a laser beam is irradiated from a head, light emitted from a molten portion is guided to one end of an optical fiber attached to the head, and a measuring unit attached to the other end of the optical fiber is used to monitor the processing status.

[0005] [Prior art literature]

[0006] [Patent Document]

[0007] Patent Document 1: International Publication No. 2018 / 185973

[0008] Patent Document 2: Japanese Patent No. 3184969 Summary of the Invention

[0009] In the laser processing devices described in Patent Documents 1 and 2, light emitted from the melted portion is measured from a measurement area located around the laser beam's irradiation position. When spot irradiation is performed, where the laser beam is directed at a single point, the melted portion forms around the laser beam's irradiation position. On the other hand, when the laser beam is irradiated while scanning, the melted portion remains molten even after the laser beam leaves the portion, extending from the irradiation position in a direction opposite to the scanning direction. Consequently, a portion of the melted portion deviates from the measurement area around the irradiation position, making it difficult to measure light emitted from the deviated melted portion. Consequently, the accuracy of the processing status evaluation may be reduced.

[0010] Therefore, an object of the present disclosure is to solve the above-mentioned problems of the prior art and to improve the evaluation accuracy of the processing state in laser processing.

[0011] A laser processing device according to one embodiment of the present invention comprises: an oscillator for oscillating a laser beam; an irradiation optical system for guiding the laser beam to a component to be processed; a measuring optical system for guiding processing light from a measurement area, the processing light including any one of thermal radiation light, plasma light, and reflected light emitted from the component by irradiation with the laser beam; a sensor for measuring the intensity of the processing light guided by the measuring optical system; a moving device for moving an irradiation point formed by the laser beam relative to the component from a starting point along a scanning path; an adjustment device for shifting the position of the measurement area relative to the position of the irradiation point; and a control unit for controlling the adjustment device so that the center of the measurement area is located at a position along the scanning path closer to the starting point than the center of the irradiation point.

[0012] According to the laser processing method according to the present disclosure, it is possible to improve the accuracy of evaluating the processing state during laser processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is an overall view of the laser processing apparatus according to the first embodiment of the present invention.

[0014] Figure 2 This is a detailed diagram of the measurement unit.

[0015] Figure 3 This is a top view of a component being spot welded.

[0016] Figure 4 This is a top view of a component during wire welding.

[0017] Figure 5 It is a diagram showing the irradiation point and the measurement area.

[0018] Figure 6A It is a diagram showing a comparative example of the shift amount and the shift direction.

[0019] Figure 6B It is a diagram showing a comparative example of the shift amount and the shift direction.

[0020] Figure 6C It is a diagram showing a comparative example of the shift amount and the shift direction.

[0021] Figure 6D It is a diagram showing a comparative example of the shift amount and the shift direction.

[0022] Figure 6E It is a diagram showing a comparative example of the shift amount and the shift direction.

[0023] Figure 7 is a graph of displacement and thermal radiation light intensity.

[0024] Figure 8A This is a top view of a component during a wire welding process in a first mode.

[0025] Figure 8B This is a top view of a component during a wire welding process in a first mode.

[0026] Figure 8C This is a top view of a component during a wire welding process in a first mode.

[0027] Figure 9 It is a graph of the intensity of thermal radiation and time.

[0028] Figure 10A This is a top view of a component during the wire welding process in the second mode.

[0029] Figure 10B This is a top view of a component during the wire welding process in the second mode.

[0030] Figure 10C This is a top view of a component during the wire welding process in the second mode.

[0031] Figure 11 It is a graph of the intensity of thermal radiation and time.

[0032] Figure 12 This is a schematic diagram of laser sealing welding of a square secondary battery.

[0033] Figure 13 This is a top view of the outer casing and sealing plate.

[0034] Figure 14A 3 is a diagram showing changes in the X coordinate of the irradiation point on the scanning path.

[0035] Figure 14B 3 is a diagram showing changes in the Y coordinate of the irradiation point on the scanning path.

[0036] Figure 15A It is a graph showing the scanning speed of the irradiation point in the X direction.

[0037] Figure 15B It is a graph showing the scanning speed of the irradiation point in the Y direction.

[0038] Figure 16A It is a diagram showing the amount of displacement in the X direction.

[0039] Figure 16B It is a diagram showing the amount of displacement in the Y direction.

[0040] Figure 17A This is a diagram showing the welding state on the first side.

[0041] Figure 17B This is a diagram showing the welding state on the second side.

[0042] Figure 17CThis is a diagram showing the welding state on the third side.

[0043] Figure 17D This is a diagram showing the welding state on the fourth side.

[0044] Figure 18 This is a plan view of laser welding of electrode terminals of a cylindrical secondary battery.

[0045] Figure 19 This is a cross-sectional view of laser welding of an electrode terminal of a cylindrical secondary battery.

[0046] Figure 20 This is a diagram showing the welding state.

[0047] Figure 21 This is an overall view of a laser processing device according to Modification 1. DETAILED DESCRIPTION

[0048] Hereinafter, embodiments of the present disclosure will be described in detail based on the accompanying drawings. Furthermore, the present disclosure is not limited to the following embodiments. Furthermore, appropriate changes can be made without departing from the scope of the effects of the present disclosure. Furthermore, the present disclosure can also be combined with other embodiments.

[0049] (Implementation 1)

[0050] Figure 1 FIG. 1 is an overall diagram of the laser processing apparatus 500 in the first embodiment of the present invention. Figure 1 As shown, laser processing apparatus 500 is an apparatus that irradiates a laser beam L1 and processes a component 9 to be processed by irradiation with the laser beam L1. Laser processing apparatus 500 includes an oscillator 1, an optical fiber 2, a positioning jig 10, an irradiation optical system 102, a moving device 6, a measuring optical system 103, an adjustment device 12, a measuring unit 17, and a control unit 18.

[0051] The oscillator 1 is a device that oscillates the laser beam L1. The oscillator 1 oscillates the laser beam L1 having a wavelength of 1070 nm, for example.

[0052] The optical fiber 2 connects the oscillator 1 and the irradiation optical system 102 . The laser beam L1 is guided from the oscillator 1 to the irradiation optical system 102 via the optical fiber 2 .

[0053] The positioning jig 10 is a jig for positioning the component 9 relative to the irradiation optical system 102 .

[0054] The irradiation optical system 102 guides the laser beam L1 to the surface of the workpiece 9 to be processed. The laser beam L1 is directed to the irradiation point (described later) by the irradiation optical system 102. Figure 3The surface of the component 9 is irradiated within the range of the irradiation point 30 in FIG. 1 . The irradiation optical system 102 includes a plurality of optical elements, such as a collimator lens 4 , a dichroic mirror 5 , and a condenser lens 8 .

[0055] The moving device 6 moves the irradiation point of the laser beam L1 relative to the component 9. The moving device 6 has, for example, a movable first mirror 6a, a movable second mirror 6b, and a first mirror control unit 7. In embodiment 1, the mirrors 6a and 6b are arranged coaxially with the irradiation optical system 102 between the dichroic mirror 5 and the focusing lens 8 to reflect the laser beam L1. The first mirror control unit 7 has a controller that controls the posture of the mirrors 6a and 6b relative to the optical axis of the irradiation optical system 102. Specifically, the first mirror control unit 7 controls the angles of the mirrors 6a and 6b. The first mirror control unit 7 controls the reflection direction of the laser beam L1 and controls the position of the irradiation point relative to the component 9 in a two-dimensional manner. For example, if the surface of the component 9 is set to an XY plane, the first mirror control unit 7 controls the X position of the irradiation point by controlling the angle of the first mirror 6a, and controls the Y position of the irradiation point by controlling the angle of the second mirror 6b. The first mirror control unit 7 controls the scanning speed of the irradiation point by controlling the rate of change (rotation speed) of the angles of the mirrors 6a and 6b, and controls the scanning direction of the irradiation point by controlling the rotation direction of the angles of the mirrors 6a and 6b. The moving device 6 can also be called a galvanometer system.

[0056] In the irradiation optical system 102, laser beam L1 passes through collimating lens 4, becoming a parallel beam. It is then bent at a right angle by dichroic mirror 5. The dichroic mirror 5 is coated so that only the wavelength of laser beam L1 (e.g., 1070 nm) is totally reflected, while all other wavelengths are transmitted. However, in this specification, "total reflection" means reflection of 99% or more, with the remaining approximately 1% of laser beam L1 being transmitted through dichroic mirror 5. Laser beam L1 reflected from dichroic mirror 5 is reflected by mirrors 6a and 6b, focused by condenser lens 8 at the irradiation point, and irradiated onto the surface of component 9.

[0057] When laser beam L1 is irradiated onto component 9, component 9 is heated and melted, forming molten zone 31. Welding light W1 is emitted from molten zone 31. Welding light W1 includes any of visible plasma light, thermal radiation light that is highly correlated with the temperature of component 9, and reflected light from laser beam L1. Welding light W1 emitted from component 9 is guided to measurement unit 17 via measurement optical system 103.

[0058] The measuring optical system 103 measures the surface of the component 9 from a measuring area (described later) Figure 3The welding light W1 is guided toward the measuring portion 17 (in the measurement area 33). The measuring optical system 103 includes a plurality of optical elements, such as a condenser lens 8, a dichroic mirror 5, a total reflection mirror 14, an imaging lens 15, and an optical fiber 16. In the first embodiment, the condenser lens 8 and the dichroic mirror 5 are shared by the measuring optical system 103 and the irradiation optical system 102.

[0059] Furthermore, the welding light W1 is reflected by mirrors 6a and 6b of a moving device 6 disposed between the condenser lens 8 and the dichroic mirror 5. Therefore, the moving device 6 moves the measurement area of ​​the welding light W1 relative to the component 9 along with the irradiation point. The scanning speed and direction of the measurement area can be the same as those of the irradiation point.

[0060] The adjustment device 12 shifts the position of the measurement area relative to the irradiation point of the laser beam L1. The adjustment device 12 includes a movable third mirror 12a, a movable fourth mirror 12b, and a second mirror control unit 13. By having mirrors 12a and 12b independent of the moving device 6, the adjustment device 12 can adjust the position of the measurement area relative to the irradiation point. In other words, the position of the measurement area relative to the component 9 is determined by the operation of both the moving device 6 and the adjustment device 12. In the first embodiment, mirrors 12a and 12b are coaxially arranged with the measurement optical system 103, between the dichroic mirror 5 and the total reflection mirror 14, to reflect the welding light W1. The second mirror control unit 13 includes a controller that controls the posture of mirrors 12a and 12b relative to the optical axis of the measurement optical system 103. Specifically, the second mirror control unit 13 controls the angles of mirrors 12a and 12b. The second mirror control unit 13 controls the reflection direction of the welding light W1, shifting the welding light W1 from the same axis as the laser beam L1, thereby controlling the amount and direction of displacement of the measurement area relative to the irradiation point.

[0061] For example, the second mirror control unit 13 controls the amount of displacement of the measurement area in the X direction by controlling the angle of the third mirror 12a, and controls the amount of displacement of the measurement area in the Y direction by controlling the angle of the fourth mirror 12b. Furthermore, the second mirror control unit 13 controls the displacement direction by combining the rotation direction of the mirrors 12a and 12b with the amount of displacement in the X and Y directions (a resultant vector).

[0062] Welding light W1 generated in the measurement area passes through condenser lens 8 and mirrors 6a and 6b, then passes through dichroic mirror 5 and is reflected by mirrors 12a and 12b. Welding light W1 reflected by mirrors 12a and 12b is bent at a right angle by total reflection mirror 14 and formed into an image on the end face of optical fiber 16 by imaging lens 15. Welding light W1 transmitted by optical fiber 16 enters measurement unit 17.

[0063] Measuring unit 17 measures the intensity of welding light W1 guided by measuring optical system 103 , and transmits an electrical signal corresponding to the intensity to control unit 18 .

[0064] The control unit 18 is a controller responsible for the overall control of the laser processing device 500. The control unit 18 includes a general-purpose processor such as a CPU or MPU that implements specified functions by executing programs. The control unit 18 implements various controls in the laser processing device 500 by calling and executing a control program stored in a memory (not shown). The control unit 18 is not limited to implementing specified functions through the collaboration of hardware and software, and can also be a specially designed hardware circuit that implements specified functions. That is, the control unit 18 can be implemented by various processors such as a CPU, MPU, GPU, FPGA, DSP, and ASIC. The control unit 18, for example, implements synchronous control of the oscillator 1, the first mirror control unit 7, and the second mirror control unit 13. In addition, the control unit 18 performs calculations on the electrical signals transmitted from the measuring unit 17 to evaluate the processing status of the execution component 9.

[0065] Next, refer to Figure 2 The measuring unit 17 will be described. Figure 2 It is a detailed diagram of the measuring unit 17.

[0066] like Figure 2 As shown, the measuring unit 17 is composed of a plurality of optical elements and sensors. For example, the measuring unit 17 includes a collimating lens 20, reflecting mirrors 21a, 21b, and 21c, filters 22a, 22b, and 22c, imaging lenses 23a, 23b, and 23c, light receiving sensors 24a, 24b, and 24c, and amplifiers 25a, 25b, and 25c.

[0067] Welding light W1 guided by optical fiber 16 is collimated by collimating lens 20 and then separated into wavelengths by multiple reflectors 21a, 21b, and 21c. In Embodiment 1, reflectors 21a, 21b, and 21c separate welding light W1 into three wavelengths. Specifically, reflector 21a separates plasma light W2 (wavelength 400-700 nm), reflector 21b separates laser reflected light W3 (wavelength 1070 nm), and reflector 21c separates thermal radiation light W4 (wavelength 1300 nm). Each reflector 21a, 21b, and 21c has a coating on its front surface that reflects only the wavelengths to be separated and transmits all other wavelengths.

[0068] Welding lights W2, W3, and W4 reflected by reflectors 21a, 21b, and 21c pass through corresponding filters 22a, 22b, and 22c. These passing welding lights W2, W3, and W4 pass through corresponding imaging lenses 23a, 23b, and 23c and are incident on corresponding light-receiving sensors 24a, 24b, and 24c. Light-receiving sensors 24a, 24b, and 24c measure the intensity of welding lights W2, W3, and W4. The intensity measured by light-receiving sensors 24a, 24b, and 24c is converted into an electrical signal by corresponding amplifiers 25a, 25b, and 25c and transmitted to control unit 18.

[0069] Here, refer to Figure 3 and Figure 4 The molten zone produced by irradiation will be described in more detail. As the workpiece 9, an example of joining two parts 9a and 9b will be described. Figure 3 It is a top view of components 9a and 9b being spot-welded. Figure 4 FIG. 1 is a top view of parts 9a and 9b during wire welding. Figure 3 and Figure 4 In the embodiment, the two components 9a, 9b are joined by welding.

[0070] like Figure 3 As shown, during spot welding, the laser beam L1 is irradiated to a point at the boundary between the components 9a and 9b. That is, the irradiation point 30 of the laser beam L1 is stationary relative to the components 9a and 9b. In the first embodiment, the irradiation point 30 is circular, but it is not limited to this. The irradiated components 9a and 9b are heated and melted, forming a molten portion 31 centered at the irradiation point 30. The molten portion 31 is larger than the irradiation point 30 and includes the irradiation point 30 and the components 9a and 9b surrounding the irradiation point 30. Since the irradiation point 30 is circular, the molten portion 31 is a circle concentric with the irradiation point 30. When the irradiation of the laser beam L1 ends, the molten portion 31 solidifies, and the components 9a and 9b are joined.

[0071] In this case, by providing the measurement region 33 including the molten portion 31 concentrically with the irradiation point 30 , the welding light W1 emitted from the molten portion 31 can be measured.

[0072] like Figure 4 As shown, during line welding, laser beam L1 scans along the boundary between components 9a and 9b. In other words, the boundary between components 9a and 9b defines a scanning path 35 for irradiation point 30. Moving device 6 causes irradiation point 30 to scan along scanning path 35 from starting point 19 on the left side in scanning direction K1.

[0073] Irradiation with laser beam L1 forms a molten zone 31, similar to spot welding. The melted parts 9a and 9b do not solidify immediately after passing through the irradiation point 30, but remain molten for a certain period of time. Therefore, the molten zone 31 has an elongated shape, extending in the direction K2 opposite to the scanning direction K1, toward the side where the irradiation point 30 has passed, that is, toward the starting point 19. Furthermore, the power of laser beam L1 increases toward the center of the irradiation point 30, so the time it remains molten increases from the edge of the irradiation point 30 toward the center of the irradiation point 30. Consequently, the molten zone 31 has a shape that tapers toward the starting point 19. The shape of the molten zone 31 varies depending on the scanning speed of the irradiation point 30, the power of laser beam L1, the absorptivity of the parts 9a and 9b, the thermal conductivity, and other factors. When the molten zone 31 solidifies, it forms a solidified zone 32, and the parts 9a and 9b are joined.

[0074] If measurement area 33 is set concentrically with irradiation point 30 for the elongated molten zone 31, molten zone 31 on the starting point 19 side will be offset from measurement area 33, making it difficult to measure welding light W1 emitted therefrom. Alternatively, measurement area 33 can be expanded to include molten zone 31 on the starting point 19 side. However, in this case, molten zone 31 becomes relatively small, reducing the intensity of welding light W1 and deteriorating the signal-to-noise ratio (SN ratio). Consequently, the measurement accuracy of welding light W1 is reduced.

[0075] Therefore, in order to measure the welding light W1 emitted from the elongated molten zone 31, the measurement area 33 is set at a position shifted relative to the irradiation point 30. Specifically, the control unit 18 uses the adjustment device 12 to shift the center of the measurement area 33 so that it is located closer to the starting point 19 than the center of the irradiation point 30 along the scanning path 35.

[0076] The displacement amount D and displacement direction L of the center C2 of the measurement area 33 relative to the center C1 of the irradiation point 30 will be described in more detail. Figure 5 3 is a diagram showing an irradiation point 30 and a measurement area 33 . Figures 6A to 6E 1 and 2 are diagrams showing comparative examples of different shift amounts D and shift directions L.

[0077] like Figure 5 As shown, the X-axis is oriented in the same direction as the scanning direction K1, with the position of the center C1 of the irradiation point 30 as the reference (X = 0). In this specification, "center" refers to the midpoint of the major axis of a certain area measured in the scanning direction K1. The shift amount D is the distance the center C2 of the measurement area 33 is displaced relative to the center C1 of the irradiation point 30, and is the size of the gap between the centers C1 and C2. The shift direction L is the direction in which the center C2 of the measurement area 33 is displaced relative to the center C1 of the irradiation point 30, and is referred to as the +X direction or -X direction in the following text.

[0078] Figure 6A The center C2 of the measurement area 33 is shifted by the amount D1 in the -X direction ( Figure 4 The state in which the measurement area 33 is moved from the irradiation point 30) is formed. Figure 6B The center C2 of the measurement area 33 is shifted by the amount D2 in the -X direction ( Figure 4 The starting point 19 side) is moved so that the entire molten portion 31 is included in the measurement area 33. Figure 6C This shows a state where the center C2 of the measurement area 33 coincides with the center C1 of the irradiation point 30 (a state where the displacement amount D=0). Figure 6D The state is shown in which the center C2 of the measurement region 33 is moved in the +X direction by a displacement amount D4 so that the entire irradiation point 30 is exactly included in the measurement region 33 . Figure 6E The state in which the center C2 of the measurement region 33 is moved in the +X direction by a displacement amount D5 so that the entire fusion zone 31 is separated from the measurement region 33 is shown.

[0079] exist Figures 6A to 6E In this case, the adjustment device 12 shifts the measurement area 33 relative to the irradiation point 30 by a shift amount D and in a shift direction L. The moving device 6 moves the irradiation point 30 and the measurement area 33 in the scanning direction K1 along the scanning path 35. Therefore, the measurement area 33 follows the irradiation point 30 while being spaced apart by the shift amount D in the shift direction L from the irradiation point 30.

[0080] Figure 7 is a graph showing the shift amount D and the intensity of the thermal radiation light measured from the measurement area 33 after the shift. Figure 7 As shown, the intensity of the thermal radiation light (i.e., welding light W1) measured by the measuring unit 17 is maximum at a displacement of D2 in the -X direction. Since the entire molten zone 31 is encompassed by the measurement region 33 shifted by the displacement D2, the light-receiving sensors 24a-24c can receive welding light W1 from the entire molten zone 31. This allows the entire processing state of the molten zone 31 to be evaluated, improving the accuracy of the processing state evaluation.

[0081] In the first embodiment, the measurement area 33 is shifted by a shift amount D2 in a direction opposite to the scanning direction K1, so that the intensity of the welding light W1 measured by the measuring unit 17 is maximized. Alternatively, another shift amount D may be applied in a direction opposite to the scanning direction K1 of the irradiation point 30. This configuration also allows measurement of the welding light W1 generated from the molten zone 31 closer to the starting point 19 than the irradiation point 30.

[0082] (action)

[0083] Here, an example of the operation of laser processing apparatus 500 will be described. As the operation of laser processing apparatus 500, control unit 18 switches between a first mode and a second mode. In the first mode, control unit 18 controls adjustment device 12 so that center C2 of measurement area 33 coincides with center C1 of irradiation point 30. In the second mode, control unit 18 controls adjustment device 12 so that center C2 of measurement area 33 is located closer to starting point 19 than center C1 of irradiation point 30.

[0084] (First Mode)

[0085] The first mode is executed, for example, during spot welding. In the first mode, the control unit 18 causes the oscillator 1 to oscillate the laser beam L1. The control unit 18 irradiates the component 9 with the laser beam L1 via the irradiation optical system 102 and the moving device 6. Specifically, the control unit 18 controls the angles of the mirrors 6a and 6b via the first mirror control unit 7 to irradiate the component 9 with the irradiation spot 30 at a predetermined position.

[0086] Next, control unit 18 directs welding light W1, emitted from component 9 by irradiation, to measurement unit 17 via measurement optical system 103. At this point, control unit 18 controls adjustment device 12 so that mirrors 12a and 12b have a reference angle. This reference angle is the angle at which welding light W1 incident on mirrors 12a and 12b becomes coaxial with laser beam L1. This operation directs welding light W1, coaxial with laser beam L1, to total reflection mirror 14, aligning center C2 of measurement area 33 with center C1 of irradiation point 30. Measurement unit 17 measures the intensity of welding light W1. Based on the measured intensity of welding light W1, control unit 18 evaluates the processing condition of component 9.

[0087] (Second Mode)

[0088] The second mode is executed when performing processing such as scanning the laser beam L1 for line welding. Below, we will examine linear line welding at a constant speed. First, the control unit 18 causes the oscillator 1 to oscillate the laser beam L1 and irradiate the component 9. When irradiating the laser beam L1, the control unit 18 controls the angles of the mirrors 6a and 6b via the first mirror control unit 7, irradiating while scanning the irradiation point 30 along the scanning path 35. Specifically, the first mirror control unit 7 controls the position of the irradiation point 30 using the angles of the mirrors 6a and 6b, controls the scanning direction using the rotation direction of the mirrors 6a and 6b, and controls the scanning speed of the irradiation point 30 using the rate of change of the angles of the mirrors 6a and 6b.

[0089] Next, control unit 18 determines the displacement amount D between center C2 of measurement area 33 and center C1 of irradiation point 30 so as to maximize the intensity of welding light W1 measured by light-receiving sensors 24a-24c. Specifically, control unit 18 determines displacement amount D based on the scanning speed of irradiation point 30 so as to maximize the measured intensity of welding light W1.

[0090] While an example of the operation for determining the shift amount D is described, the present invention is not limited thereto. For example, the control unit 18 obtains the rate of change of the angles of the mirrors 6a and 6b (i.e., the scanning speed of the irradiation point 30). The maximum intensity position at which the welding light W1 reaches its maximum intensity is stored in the memory of the control unit 18, corresponding to the scanning speed of each irradiation point 30. The control unit 18 references the memory to obtain the maximum intensity position corresponding to the applied scanning speed, and determines the distance from the center C1 of the irradiation point 30 to the maximum intensity position as the shift amount D.

[0091] Furthermore, the control unit 18 may determine the shift amount D based on information input from the outside, such as the operation of the oscillator 1 , such as the power or wavelength of the laser beam L1 , or the material of the component 9 .

[0092] The control unit 18 obtains the settings of the adjustment device 12 for achieving the determined shift amount D. For example, the memory of the control unit 18 stores the angles of the mirrors 12a and 12b for achieving the shift amount D, corresponding to each shift amount D. The control unit 18 refers to the memory and obtains the angles of the mirrors 12a and 12b.

[0093] Next, the control unit 18 determines the displacement direction L of the measurement area 33 based on the scanning direction K1 of the irradiation point 30. The displacement direction L is opposite to the scanning direction K1.

[0094] Therefore, the control unit 18 controls the adjustment device 12 based on the displacement amount D and the displacement direction L. Specifically, the control unit 18 controls the angles of the mirrors 12a and 12b via the second mirror control unit 13, rotating the mirrors 12a and 12b in a direction opposite to the rotation direction of the mirrors 6a and 6b to an angle that achieves the displacement amount D. In the case of wire welding at a constant speed, the control unit 18 maintains the rotation of the mirrors 12a and 12b and performs the welding process.

[0095] Next, the control unit 18 causes the measuring unit 17 to measure the welding light W1 derived from the displaced measurement region 33 .

[0096] To summarize the above operations, control unit 18 determines the shift amount D and shift direction L based on the scanning speed and scanning direction K1 of irradiation point 30, and controls adjustment device 12 to shift measurement area 33. Considering that the movement of irradiation point 30 is determined by the angles of mirrors 6a and 6b, and the shift amount D and shift direction L are determined by mirrors 12a and 12b, control unit 18 controls the angles of mirrors 12a and 12b based on the angles of mirrors 6a and 6b.

[0097] Through this operation, the center C2 of the measurement area 33 is located on the starting point 19 side relative to the center C1 of the irradiation point 30 along the scanning path 35, and the measurement area 33 includes the molten zone 31 on the starting point 19 side. Therefore, the welding light W1 generated on the starting point 19 side of the irradiation point 30 can be easily guided to the measurement unit 17. Therefore, the measurement unit 17 can monitor the entire processing state of the molten zone 31, and the accuracy of the processing state evaluation is improved.

[0098] Reference Figures 8A to 11 , the effect of executing the second mode instead of the first mode when scanning the laser beam L1 for processing is described in more detail. Figures 8A to 8C This is a plan view of components 9a and 9b during the wire welding process in the first mode. Figure 9 Is the time passed and Figures 8A to 8C Graph of the thermal radiation light intensity measured in . 10A to 10C This is a plan view of the components 9a and 9b during the wire welding process in the second mode. Figure 11 Is the time passed and 10A to 10C Graph showing the thermal radiation intensity measured in .

[0099] Figures 8A to 8C The states at times T1, T2, and T3 during execution of the first mode are respectively shown. Figure 8A and Figure 8C Indicates a normal processing state. When the first mode is executed, in a normal processing state, the portion of the molten portion 31 on the starting point 19 side is located outside the measurement area 33. On the other hand, Figure 8B This indicates an abnormal processing state, where the molten portion 31 is shortened. Therefore, the entire molten portion 31 is contained within the measurement region 33 , and no molten portion 31 is formed outside the measurement region 33 .

[0100] like Figure 9 As shown in FIG. 3 , the thermal radiation light intensity slightly decreases at time T2 when an abnormal processing state occurs. Since most of the shortened portion of the molten portion 31 is outside the measurement area 33, it is difficult to distinguish the decrease in thermal radiation light intensity caused by the abnormal processing state from the signal noise. Figure 9 The time change of the thermal radiation light intensity is used to determine whether an abnormal processing state has occurred.

[0101] 10A to 10C The states at times T1, T2, and T3 during execution of the second mode are respectively shown. Figure 10A and Figure 10C Indicates normal processing status, Figure 10B Indicates an abnormal processing state. When the second mode is executed, the entire molten zone 31 is located inside the measurement region 33 in both the normal processing state and the abnormal processing state.

[0102] like Figure 11 As shown in FIG. 1 , the entire molten portion 31 is located inside the measurement region 33. Therefore, at the time T1 and T3 when the normal processing state is generated, the thermal radiation light intensity is greater than Figure 9 Therefore, at time T2 when an abnormal processing state occurs, the decrease in the intensity of the thermal radiation light becomes significant. Therefore, by executing the second mode while scanning the laser beam L1 for processing, it is easy to determine whether an abnormal processing state has occurred based on the time change of the thermal radiation light intensity.

[0103] (Action example: laser sealing welding)

[0104] Next, a specific operation example of the laser processing apparatus 500 will be described. Figure 12 This is a schematic diagram of laser sealing welding of square secondary batteries. Figure 12 As shown in the figure, during laser sealing welding, a cover called a sealing plate 41 is inserted into the outer casing 40 of the prismatic secondary battery. A laser beam is then scanned along the circumference of the sealing plate 41 for one full circle to weld the outer casing 40. The quality of laser sealing welding greatly affects the product quality of the prismatic secondary battery. Therefore, during laser sealing welding, the process is sometimes performed while the processing status is evaluated.

[0105] Figure 13 4 is a top view of the outer shell 40 and the sealing plate 41. Figure 13 As shown, the irradiation point 30 of the laser beam L1 is scanned along the boundary between the outer shell 40 and the sealing plate 41. Therefore, the scanning path 35 is defined by the boundary between the outer shell 40 and the sealing plate 41. The scanning path 35 has a substantially rectangular shape including a first side S1, a second side S2, a third side S3, and a fourth side S4. The irradiation point 30 is scanned, for example, in the order of the first side S1, the second side S2, the third side S3, and the fourth side S4. Therefore, the starting point 19 of the scanning path 35 of the irradiation point 30 is, for example, the corner between the first side S1 and the fourth side S4. In addition, when the XY axis is taken with the center of the sealing plate 41 as the reference (0,0), the first side S1 corresponds to X=+X0, the second side S2 corresponds to Y=-Y0, the third side S3 corresponds to X=-X0, and the fourth side S4 corresponds to Y=+Y0.

[0106] Since the laser beam L1 is scanned, laser sealing welding is performed in the second mode. In this operation example, unlike the above-mentioned line welding, the scanning path 35 is curved, so the direction in which the center C2 of the measurement area 33 is offset from the irradiation point 30, that is, the shift direction L, is changed midway.

[0107] The shift direction L will be described in more detail. First, the movement of the irradiation point 30 will be considered. Figure 14A 3 is a diagram showing changes in the X coordinate of the irradiation point 30 in the scanning path 35 . Figure 14B 35 is a diagram showing the change in the Y coordinate of the irradiation point 30 in the scanning path 35. Figure 14A as well as Figure 14B As shown, on the first side S1, the X coordinate of the irradiation point 30 is X0, and the Y coordinate changes from Y0 to -Y0. On the second side S2, the Y coordinate of the irradiation point 30 is -Y0, and the X coordinate changes from X0 to -X0. On the third side S3, the X coordinate of the irradiation point 30 is -X0, and the Y coordinate changes from -Y0 to Y0. On the fourth side S4, the Y coordinate of the irradiation point 30 is Y0, and the X coordinate changes from -X0 to X0. Here, the meaning of "-" indicates the negative direction relative to the X direction or the Y direction. In addition, in this one-round welding, for example, when moving from the first side S1 to the second side S2, the movement actually follows a curved shape, but this part is omitted in this example.

[0108] The irradiation point 30 moves at a constant speed, and the magnitude of the speed is set to V0. Figure 15A is a diagram showing the scanning speed of the irradiation point 30 in the X direction. Figure 15B is a diagram showing the scanning speed in the Y direction of the irradiation point 30. Figure 15A and Figure 15B As shown, the scanning speed of the irradiation point 30 is -V0 in the Y direction at the first side S1, -V0 in the X direction at the second side S2, +V0 in the Y direction at the third side S3, and +V0 in the X direction at the fourth side S4. Therefore, the scanning direction K1 of the irradiation point 30 is -Y direction at the first side S1, -X direction at the second side S2, +Y direction at the third side S3, and +X direction at the fourth side S4.

[0109] The control unit 18 determines the shift direction L based on the scanning direction K1 of the irradiation point 30. Specifically, the control unit 18 determines the direction opposite to the scanning direction K1 of the irradiation point 30 as the shift direction L. Therefore, regardless of the scanning direction K1 of the irradiation point 30, the center C2 of the measurement area 33 is located on the starting point 19 side along the scanning path 35.

[0110] Figure 16A is a diagram showing the displacement amount Dx in the X direction, Figure 16B is a diagram showing the displacement Dy in the Y direction. Figure 16A and Figure 16B As shown, on the first side S1, the shift amount Dy is +D0, on the second side S2, the shift amount Dx is +D0, on the third side S3, the shift amount Dy is -D0, and on the fourth side S4, the shift amount Dx is -D0. That is, the magnitude of the shift amount Dx or the shift amount Dy is constant D0, but the shift direction L is different. On the first side S1, the shift direction L is the +Y direction, on the second side S2, the shift direction L is the +X direction, on the third side S3, the shift direction L is the -Y direction, and on the fourth side S4, the shift direction L is the -X direction. Figure 15A and Figure 15B In contrast, the signs of the scanning speed and the shift direction L of the irradiation point 30 are opposite.

[0111] 17A to 17D The figures show the welding conditions at the first side S1 to the fourth side S4. 17A to 17D As shown, regardless of the scanning direction K1 of the irradiation point 30 , welding light generated from the elongated molten zone 31 generated behind the scanning direction K1 of the irradiation point 30 can be measured.

[0112] (Action example: overlapping laser welding)

[0113] Next, different operation examples of the laser processing apparatus 500 will be described. Figure 18 This is a plan view of laser welding of electrode terminals of a cylindrical secondary battery. Figure 19 This is a cross-sectional view of laser welding of the electrode terminal of a cylindrical secondary battery. In laser welding of the electrode terminal, the electrode terminal 43 of the cylindrical secondary battery is overlapped with the electrode plate 44, and laser is irradiated from the overlapping direction to perform welding. Figure 18 and Figure 19 As shown, the electrode terminal 43 and the electrode plate 44 are joined at the solidified portion 32. The quality of the overlap laser welding greatly affects the product quality of the cylindrical secondary battery. Therefore, during overlap laser welding, the processing is sometimes performed while the processing status is evaluated.

[0114] Since the laser beam L1 is scanned, overlapping laser welding is performed by the second mode. Figure 20 It is a diagram showing the welding state. Figure 20 As shown, the measurement area 33 is shifted in the direction opposite to the scanning direction of the irradiation point 30. In this example, the overlapping laser welding is a line welding at a constant speed and a constant length, and the shift amount D and shift direction L of the measurement area 33 are constant.

[0115] (Effect)

[0116] According to the laser processing apparatus 500 of the first embodiment, the following effects can be achieved.

[0117] As described above, laser processing apparatus 500 includes an oscillator 1, an irradiation optical system 102, a measurement optical system 103, sensors (light-receiving sensors 24a to 24c), a moving device 6, an adjustment device 12, and a control unit 18. Oscillator 1 oscillates laser beam L1. Irradiation optical system 102 guides laser beam L1 toward component 9, the processing target. Measurement optical system 103 guides processing light (welding light W1), including any of thermal radiation light, plasma light, and reflected light emitted from component 9 by irradiation with laser beam L1, from measurement region 33. Light-receiving sensors 24a to 24c measure the intensity of welding light W1 guided by measurement optical system 103. Moving device 6 moves irradiation point 30 of laser beam L1 relative to component 9 along scanning path 35 from starting point 19. Adjustment device 12 shifts the position of measurement region 33 relative to the position of irradiation point 30. The control unit 18 controls the adjustment device 12 so that the center C2 of the measurement area 33 is located closer to the starting point 19 than the center C1 of the irradiation point 30 along the scanning path 35 .

[0118] With this configuration, the molten portion 31 formed on the starting point 19 side of the irradiation point 30 can be included in the measurement region 33. Therefore, the welding light W1 generated from the molten portion 31 formed on the starting point 19 side of the irradiation point 30 can be guided to the measurement portion 17. Consequently, the accuracy of the evaluation of the processing state of the laser processing apparatus 500 is improved.

[0119] In the laser processing apparatus 500 , the moving device 6 moves the irradiation point 30 and the measurement region 33 relative to the component 9 along the scanning path 35 from the starting point 19 .

[0120] According to this configuration, by providing a common moving device 6 for moving the irradiation point 30 and the measurement area 33, the measurement area 33 can be moved together with the irradiation point 30. Therefore, it is easy to maintain a predetermined displacement amount D between the measurement area 33 and the irradiation point 30.

[0121] In laser processing apparatus 500 , moving device 6 includes movable mirrors 6 a and 6 b for reflecting laser beam L1 and welding light W1 . Irradiation optical system 102 and measurement optical system 103 include a common condenser lens 8 disposed between moving device 6 and component 9 .

[0122] With this configuration, laser beam L1 and welding light W1, after their travel directions are changed by a shared moving device 6, pass through a shared condenser lens 8 and reach component 9. This facilitates bringing measurement region 33 and irradiation point 30 close together, allowing irradiation point 30 to be included in measurement region 33. In other words, it is possible to prevent measurement region 33 and irradiation point 30 from becoming too far apart.

[0123] In the laser processing apparatus 500 , the moving device 6 includes a movable first mirror 6 a and a movable second mirror 6 b , and the adjusting device 12 includes a movable third mirror 12 a and a movable fourth mirror 12 b .

[0124] With this configuration, by moving mirrors 6a and 6b, irradiation point 30 and measurement area 33 can be moved in the same manner, that is, at the same scanning speed and in the same scanning direction. By moving mirrors 12a and 12b, measurement area 33 can be offset relative to irradiation point 30. Furthermore, since moving device 6 and adjustment device 12 each include two mirrors, irradiation point 30 and measurement area 33 can be moved two-dimensionally.

[0125] In the laser processing apparatus 500 , the control unit 18 controls the angle of the third mirror 12 a and the fourth mirror 12 b based on the angle of the first mirror 6 a and the second mirror 6 b .

[0126] With such a configuration, the measurement region 33 can be shifted relative to the irradiation point 30 based on the position of the irradiation point 30 , the scanning speed, the scanning direction, and the like.

[0127] In the laser processing apparatus 500, the control unit 18 controls the adjustment device 12 so as to be switchable between a first mode and a second mode. In the first mode, the center C2 of the measurement area 33 coincides with the center C1 of the irradiation point 30. In the second mode, the center C2 of the measurement area 33 is located closer to the starting point 19 than the center C1 of the irradiation point 30.

[0128] This structure allows for high-precision evaluation of the processing state even in processes such as spot welding where the molten zone 31 is formed only around the irradiation point 30. Furthermore, since the irradiation optical system 102 and the measurement optical system 103 are partially shared, the structure of the laser processing apparatus 500 is simplified.

[0129] In the laser processing apparatus 500 , the control unit 18 controls the adjustment device 12 based on the scanning speed of the irradiation point 30 .

[0130] With such a configuration, even for the molten portion 31 having a range and shape that changes depending on the scanning speed of the irradiation spot 30 , the adjustment device 12 can be controlled so that the entire molten portion 31 is included in the measurement region 33 .

[0131] In laser processing apparatus 500 , control unit 18 determines a displacement D of center C2 of measurement area 33 relative to center C1 of irradiation point 30 based on the scanning speed of irradiation point 30 so as to maximize the intensity of welding light W1 measured by light receiving sensors 24 a to 24 c .

[0132] With this configuration, more molten portions 31 are included in the measurement region 33, and the light receiving sensors 24a to 24c can receive more welding light W1. Therefore, the accuracy of the evaluation of the processing state is further improved.

[0133] In the laser processing apparatus 500 , the control unit 18 determines the shift direction of the center C2 of the measurement area 33 relative to the center C1 of the irradiation point 30 based on the scanning direction K1 of the irradiation point 30 .

[0134] This configuration allows the measurement region 33 to be displaced in the direction opposite to the scanning direction K1 of the irradiation spot 30. Furthermore, even for the molten portion 31 whose extending direction changes according to the scanning direction of the irradiation spot 30, the adjustment device 12 can be controlled so that the entire molten portion 31 is included in the measurement region 33.

[0135] Furthermore, while the first embodiment describes an example in which the laser processing apparatus 500 is used for laser welding, the present invention is not limited thereto. The laser processing apparatus 500 may also be used for other processing methods in which a component to be processed is melted by laser irradiation. In this case, the welding light W1 from the molten zone in the first embodiment may also be referred to as processing light.

[0136] Furthermore, in Embodiment 1, an example is described in which the moving device 6 includes movable mirrors 6a and 6b, but this is not limiting. The moving device 6 may be any device that changes the relative positions of the irradiation point 30 and the measurement area 33 with respect to the component 9. For example, as described in Modification 1 below, the moving device 6 may be a movable stage that supports the component 9. Furthermore, the moving device 6 may be a head that moves the irradiation optical system 102 and the measurement optical system 103 relative to the component 9.

[0137] In addition, in the first embodiment, an example is described in which the moving device 6 scans both the irradiation point 30 and the measurement area 33, but the present invention is not limited to this. The measurement area 33 may also be scanned by a moving device different from the moving device 6. In this case, the irradiation optical system 102 and the measurement optical system 103 may be configured independently of each other.

[0138] Furthermore, in the first embodiment, the irradiation spot 30 and the measurement region 33 are described as circular, but the present invention is not limited thereto and the irradiation spot 30 and the measurement region 33 may have any shape.

[0139] Furthermore, in the first embodiment, the example in which the control unit 18 executes the second mode when the irradiation point 30 of the laser beam L1 is scanned on the component 9 is described. However, the present invention is not limited to this. For example, when the power of the laser beam L1 is low and the scanning speed of the irradiation point 30 is slow, the control unit 18 may execute the first mode.

[0140] In addition, while the first embodiment describes an example in which the intensity of the welding light is determined in the second mode so as to maximize the intensity of the measured displacement amount D, the present invention is not limited thereto. For example, if the diameter of the measurement region 33 is smaller than the length of the molten zone 31, the control unit 18 may determine the displacement amount D so that the measurement region 33 exactly includes the end of the molten zone 31 on the starting point 19 side. With this displacement amount D, the end of the molten zone 31 on the starting point 19 side is included in the measurement region 33. This facilitates detection of machining abnormalities such as shortening of the molten zone 31.

[0141] In addition, in the first embodiment, the control unit 18 controls the adjustment device 12 based on the operation of the moving device 6 (the scanning speed and scanning direction of the irradiation point 30). However, the present invention is not limited to this. The control unit 18 may also control the adjustment device 12 based on other information such as the processing program. In addition, in the case of straight line welding at a constant speed, the control unit 18 may also apply a predetermined displacement amount D and displacement direction L.

[0142] In addition, in the first embodiment, the example in which the irradiation spot 30 moves at a constant scanning speed is described, but the present invention is not limited to this. The control unit 18 may also change the scanning speed of the irradiation spot 30. In this case, the control unit 18 may also control the shift amount D according to the change in the scanning speed.

[0143] (Variation 1)

[0144] Figure 21 FIG. 6 is an overall diagram of the laser processing device 600 according to the first modification. Figure 21 As shown, the laser processing apparatus 600 includes a table 29 instead of the moving device 6 and an adjustment mechanism 50 instead of the adjustment device 12. Unless otherwise specified, the structure of the laser processing apparatus 600 may be the same as that of the laser processing apparatus 500 of the first embodiment.

[0145] The work table 29 is a movable work table. The work table 29 can move in one direction or in multiple dimensions. The movement of the work table 29 is controlled by the control unit 18.

[0146] The adjustment mechanism 50 is provided on the imaging lens 15 and is capable of shifting the image formation position of the imaging lens 15 in a direction intersecting the optical axis of the imaging lens 15. For example, the adjustment mechanism 50 may be a mechanism that moves the imaging lens 15 relative to the optical axis of the measurement optical system 103. By adjusting the image formation position in a direction intersecting the optical axis, the position of the measurement area 33 can be changed. When the scanning speed of the irradiation point 30 is constant, the position of the measurement area 33 is also adjusted once by the adjustment mechanism 50. This eliminates the need to monitor the operation of the workbench 29 and adjust the adjustment mechanism 50 at any time. The adjustment mechanism 50 is controlled by the control unit 18. The control unit 18 can also operate the adjustment mechanism 50 by a predetermined adjustment amount to adjust the image formation position of the imaging lens 15.

[0147] Here, the operation of the laser processing device 600 will be described using an example in which electrode terminal 43 and electrode plate 44 are overlapped and welded. Electrode plate 44 is placed on the worktable 29, and electrode terminal 43 is placed thereon. The control unit 18 irradiates the electrode terminal 43 with a laser beam L1. The worktable 29 moves linearly, and the electrode terminal 43 and electrode plate 44 are welded linearly. The control unit 18 adjusts the imaging position of the imaging lens 15 using the adjustment mechanism 50, shifting the measurement area 33 relative to the irradiation point 30.

[0148] The laser processing device in the first embodiment includes: an oscillator for oscillating a laser beam; an irradiation optical system for guiding the laser beam to a component to be processed; a measurement optical system for guiding processing light from a measurement area, the processing light including any one of thermal radiation light, plasma light, and reflected light emitted from the component by irradiation with the laser beam; a sensor for measuring the intensity of the processing light guided by the measurement optical system; a moving device for moving the irradiation point formed by the laser beam relative to the component from a starting point along a scanning path; an adjustment device for shifting the position of the measurement area relative to the position of the irradiation point; and a control unit for controlling the adjustment device so that the center of the measurement area is located at a position along the scanning path closer to the starting point than the center of the irradiation point.

[0149] As a laser processing apparatus according to a second aspect, in the laser processing apparatus according to the first aspect, the moving device moves the irradiation point and the measurement area relative to the component along the scanning path from the starting point.

[0150] As a laser processing apparatus according to a third aspect, in the laser processing apparatus according to the second aspect, the moving device has a movable mirror for reflecting the laser beam and processing light, and the irradiation optical system and the measurement optical system have a common condenser lens arranged between the moving device and the component.

[0151] As a laser processing apparatus according to a fourth aspect, in the laser processing apparatus according to the third aspect, the moving device includes a movable first mirror and a movable second mirror, and the adjusting device includes a movable third mirror and a movable fourth mirror.

[0152] As a laser processing apparatus according to a fifth aspect, in the laser processing apparatus according to the fourth aspect, the control unit controls the angle of the third mirror and the fourth mirror based on the angle of the first mirror and the second mirror.

[0153] As a laser processing device in the sixth mode, in the laser processing device in any one of the first to fifth modes, the control unit performs control of the adjustment device in a manner capable of switching between a first mode and a second mode, wherein the center of the measurement area in the first mode is consistent with the center of the irradiation point, and the center of the measurement area in the second mode is located at a position closer to the starting point than the center of the irradiation point.

[0154] As a seventh aspect, in the laser processing apparatus according to any one of the first to sixth aspects, the control unit controls the adjustment device based on a scanning speed of the irradiation point.

[0155] As the laser processing device in the eighth aspect, in the laser processing device in the seventh aspect, the control unit determines the displacement amount of the center of the measurement area relative to the center of the irradiation point according to the scanning speed of the irradiation point so that the intensity of the processing light measured by the sensor becomes maximum.

[0156] As a ninth aspect, in the laser processing apparatus according to any one of the first to eighth aspects, the control unit determines a shift direction of the center of the measurement area relative to the center of the irradiation point based on a scanning direction of the irradiation point.

[0157] While the present disclosure has been fully described in connection with the preferred embodiments thereof with reference to the accompanying drawings, various changes and modifications will be apparent to those skilled in the art and are to be construed as being included therein as long as they do not depart from the scope of the present invention as defined by the appended claims.

[0158] [Industrial Applicability]

[0159] The laser processing apparatus disclosed herein is particularly useful as a laser processing apparatus that performs processing such as laser welding while monitoring the processing status in real time.

[0160] [Explanation of Reference Numerals]

[0161] 1 oscillator

[0162] 6 mobile devices

[0163] 6a Mirror

[0164] 6b Mirror

[0165] 7First mirror control unit

[0166] 9 parts

[0167] 12 Adjustment device

[0168] 12a Mirror

[0169] 12b Mirror

[0170] 13 Second mirror control unit

[0171] 17 Measurement Department

[0172] 30 irradiation points

[0173] 31 Melting section

[0174] 33 measurement area

[0175] 102 Illumination Optical System

[0176] 103 Measurement Optical System

[0177] 500 laser processing device

[0178] W1 welding light

[0179] D shift amount

Claims

1. A laser processing device comprising: an oscillator, oscillating a laser beam; an irradiation optical system for directing the laser beam to a component to be processed; a measuring optical system that guides processing light from a measuring area, the processing light including any one of heat radiation light, plasma light, and reflected light emitted from the component by irradiation with the laser beam; a sensor that measures the intensity of the processing light guided by the measuring optical system; a moving device for moving the irradiation point formed by the laser beam relative to the component along a scanning path from a starting point; an adjustment device for shifting the position of the measurement area relative to the position of the irradiation point; and The control unit controls the adjustment device so that the center of the measurement area is located closer to the starting point than the center of the irradiation point along the scanning path.

2. The laser processing device according to claim 1, wherein: The moving device moves the irradiation point and the measurement area relative to the component along the scanning path from the starting point.

3. The laser processing device according to claim 2, wherein: The moving device has a movable mirror for reflecting the laser beam and the processing light. The irradiation optical system and the measurement optical system include a common condenser lens disposed between the moving device and the component.

4. The laser processing device according to claim 3, wherein: The moving device includes a movable first mirror and a movable second mirror, and the adjusting device includes a movable third mirror and a movable fourth mirror.

5. The laser processing device according to claim 4, wherein: The control unit controls the angle of the third mirror and the fourth mirror based on the angle of the first mirror and the second mirror.

6. The laser processing device according to any one of claims 1 to 5, wherein: The control unit controls the adjustment device in a manner that is switchable between a first mode in which the center of the measurement area coincides with the center of the irradiation point and a second mode in which the center of the measurement area is located closer to the starting point than the center of the irradiation point.

7. The laser processing device according to any one of claims 1 to 5, wherein The control unit controls the adjustment device based on a scanning speed of the irradiation point.

8. The laser processing device according to claim 7, wherein: The control unit determines a displacement amount of the center of the measurement area relative to the center of the irradiation point based on a scanning speed of the irradiation point so that the intensity of the processing light measured by the sensor becomes maximum.

9. The laser processing device according to any one of claims 1 to 5, wherein: The control unit determines a shift direction of the center of the measurement area relative to the center of the irradiation point based on a scanning direction of the irradiation point.

Images