Welding method and laser processing device

Abstract

The present invention provides a welding method for metal welding by laser welding, which can maintain good welding quality and shorten processing time at the same time. A welding method in which an end surface at which end portions of a first member and a second member abut against each other is disposed so as to face a laser device (1) and welding is performed by means of a laser beam, the welding method being characterized by comprising: a first step in which the laser beam is irradiated onto the first member to form a first melted portion; a second step of irradiating the second member with laser light to form a second melted portion; and a third step in which, when the first melted part and the second melted part are joined, laser light comprising a first laser light and a second laser light having different wavelengths is irradiated onto the joined first melted part and second melted part to form one melted part.

Description

Technical Field

[0001] The invention relates to a welding method for metal welding using laser and a laser processing device. Background Art

[0002] Laser welding using laser is one of the technologies for metal welding. Compared with other welding technologies, laser welding can weld the workpiece using high-density energy through a focusing lens, and is suitable for high-quality and fine welding.

[0003] In recent years, laser welding has been used to manufacture stators (stators) for motors assembled in hybrid vehicles or electric vehicles. The stator consists of a stator core and multiple segmented coils installed in the stator core slots, and the ends of the corresponding segmented coils are connected together by laser welding. Usually, each segmented coil uses a rectangular conductor, and the welding surface is very small, only a few millimeters square, so it is suitable for laser welding.

[0004] However, in the front end welding process of the rectangular conductor, a gap or step difference may occur when the front ends are butted due to the influence of the deviation of the processing accuracy, the mechanical accuracy of the fixing jig, the thickness of the conductor coating, etc. In such a case, if the laser is continuously irradiated across the two rectangular conductors, the laser may penetrate through the gap, and the laser may irradiate the lower part of the rectangular conductor, causing carbonization and poor insulation.

[0005] Patent Document 1 discloses a front end welding process of a rectangular wire, wherein the technique is disclosed in which welding is performed while filling the gap with molten metal in order to prevent laser penetration when there is a gap between two rectangular wires. In particular, the technique is characterized in that welding is performed while suppressing a scanning trajectory of energy density at the start of irradiation in order to prevent a large amount of sputtering due to high energy density on the welding surface at the start of laser irradiation.

[0006] Patent Document 2 discloses a welding method for preventing laser light from penetrating through a gap between electrical conductors when joining the ends of electrical conductors. Specifically, two adjacent electrical conductors are welded to form molten portions. Then, pressure is applied by a pressing mechanism to bring the ends closer to each other, thereby joining the molten portions together. This makes it possible to join the ends of the electrical conductors together without having to butt them together with high precision.

[0007] Prior art literature

[0008] Patent Literature

[0009] Patent Document 1: Japanese Patent Application Publication No. 2019-181506

[0010] Patent Document 2: Japanese Patent Application Publication No. 2020-142257 Summary of the invention

[0011] Problem that the invention aims to solve

[0012] However, if the laser is continuously scanned across two rectangular lines as in Patent Document 1, a large amount of sputtering may sometimes occur when crossing the step difference. In addition, if the laser is uniformly scanned across the left and right rectangular lines without considering the step difference, this may cause the height of the molten part to be different on the left and right, resulting in loss of balance and reduced welding strength.

[0013] Furthermore, if the technique of Patent Document 2 is used to bring the ends close to each other by pressing force to join the molten parts, the joined molten parts may tilt, and the molten parts may overflow from the end faces, making it difficult to form a beautiful molten bead. When the molten bead formed at the front end tilts or overflows, there is a problem that the required welding quality cannot be achieved and the welding strength is reduced.

[0014] Therefore, the present invention is proposed in view of the above-mentioned problems, and its purpose is to provide a welding method and a laser processing device that can ensure good welding quality and welding strength without causing laser penetration from the gap of the rectangular conductor during the welding method for the front end of the rectangular conductor.

[0015] Means of solving the problem

[0016] In order to solve the above-mentioned problem, the present invention is characterized in that it is a welding method in which the end faces of the ends of the first component and the second component are arranged relative to a laser device and welded by laser, which comprises: a first step of irradiating the first component with the laser to form a first molten portion; a second step of irradiating the second component with the laser to form a second molten portion; and a third step of irradiating the combined first molten portion and the second molten portion with the laser to form a molten portion when the first molten portion and the second molten portion are combined, wherein the laser is composed of a first laser and a second laser having different wavelengths.

[0017] Effects of the Invention

[0018] According to the present invention, even if a gap is generated when the front ends of the rectangular wires are butted, the third step is performed after the two molten parts are joined in the first and second steps, thereby preventing the laser from passing through the gap and damaging the lower part of the rectangular conductor. In addition, by irradiating the molten parts joined in the third step with laser, the molten parts can be made uniform, forming beautiful molten beads that are bilaterally symmetrical. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] [ Figure 1 ] is a diagram showing the appearance of the laser processing device 1.

[0020] [ Figure 2] is a diagram showing the functional structure of the laser processing device 1.

[0021] [ Figure 3 ] is a diagram showing the structure of the hybrid galvanometer scanner 10.

[0022] [ Figure 4 ] is a diagram for explaining the function of the focus shift unit 6.

[0023] [ Figure 5 ] is a diagram for explaining the function of the galvanometer scanning unit 8.

[0024] [ Figure 6 ] is a diagram showing the structure of a hybrid galvanometer scanner 10a as a modified example.

[0025] [ Figure 7 ] is a diagram showing the structure of a hybrid galvanometer scanner 10b as a modified example.

[0026] [ Figure 8 ] is a three-dimensional diagram showing the schematic structure of a stator as a workpiece.

[0027] [ Fig. 9 ] are diagrams for explaining positional deviations of the rectangular wires (segment coils) 52 (a) to (c) in the xyθ direction.

[0028] [ Fig.10 ] is a diagram for explaining the step difference of the rectangular line 52 in the z direction.

[0029] [ Fig.11 ] is a block diagram showing the functional structure of the image processing unit 9.

[0030] [ Fig.12 ] is a diagram for explaining the coordinate values ​​measured by the image processing unit 9.

[0031] [ Fig.13 ] is a diagram for explaining the coordinate values ​​measured by the image processing unit 9.

[0032] [ Fig.14 ] is a block diagram showing the functional structure of controlling PC12.

[0033] [ Fig.15 ] is a flow chart showing the actions of laser processing by the laser processing device 1.

[0034] [ Fig.16 ] is a diagram showing an example of a registration screen 150.

[0035] [ Fig.17 ] is a flowchart showing the measurement processing actions of the image processing unit 9.

[0036] [ Fig.18] is a flowchart showing the measurement processing actions of the image processing unit 9.

[0037] [ Fig.19 ] is a diagram for explaining marks (numbers).

[0038] [ Fig. 20 ] is a diagram for explaining the first spot analysis process (height binarization).

[0039] [ Fig.21 ] (a) is image data showing the center position measured by the first spot analysis process. (b) is a diagram for explaining the setting of the mask area. (c) is image data showing the center position measured by the second spot analysis process.

[0040] [ Fig. 22 ] is a diagram used to illustrate the height measurement process.

[0041] [ Fig.23 ] is a diagram showing the data structure of the coordinate table 113.

[0042] [ Fig.24 ] (a) is a diagram showing the laser irradiation trajectory of the first step. (b) is a diagram showing the laser irradiation trajectory of the second step. (c) is a diagram showing the laser irradiation trajectory of the third step.

[0043] [ Fig.25 ](a) to (f) are diagrams for explaining the shape change of the workpiece W (welding surface).

[0044] [ Fig.26 ](a) to (d) are diagrams showing modified examples of the third step.

[0045] [ Fig. 27 ] is a diagram for illustrating the effect of a modified example of step 3.

[0046] [ Fig.28 ] is a flow chart showing the actions of laser processing.

[0047] [ Fig.29 ] is a diagram showing the data structure of the processing rate table 1100.

[0048] [ Fig.30 ] (a) is a schematic diagram for explaining the processing of the first step when there is a step difference. (b) is a schematic diagram for explaining the processing of the second step when there is a step difference. (c) is a schematic diagram for explaining the processing of the third step when there is a step difference.

[0049] [ Fig.31](a) is a schematic diagram for explaining the processing of the first step when there is a positional offset in the xyθ direction. (b) is a schematic diagram for explaining the processing of the second step when there is a positional offset in the xyθ direction. (c) is a schematic diagram for explaining the processing of the third step when there is a positional offset in the xyθ direction.

[0050] [ Fig.32 ] is a diagram used to illustrate the correction of processed graphic data.

[0051] [ Fig.33 ](a) to (e) are diagrams for illustrating variations of the third step.

[0052] [ Fig.34 ] (a) to (c) are schematic diagrams for explaining the change of the weld surface from the start of processing to the end of processing. (d) is a schematic diagram showing the weld surface after processing in a conventional example.

[0053] [ Fig.35 ] is a diagram showing an example of the main screen 160.

[0054] [ Fig.36 ] is a diagram showing an example of a processing graphic data registration screen 170.

[0055] [ Fig.37 ] is a diagram showing an example of a processing position confirmation screen 180.

[0056] [ Fig.38 ] is a block diagram showing the functional structure of the control PC 22 of implementation mode 2.

[0057] [ Fig.39 ] (a) is a perspective view showing a schematic structure of a stator as a welding target in Embodiment 2. (b) is an enlarged view of a rectangular line 52 and a rectangular line 53 in Embodiment 2.

[0058] [ Fig.40 ] is a diagram used to illustrate the reflection of laser during processing.

[0059] [ Fig.41 ] is a diagram used to illustrate the irradiation prohibited area.

[0060] [ Fig.42 ] is a diagram for explaining a drawn pattern.

[0061] [ Fig.43 ] is a diagram showing an example of the configuration of rectangular lines.

[0062] [ Fig.44 ] is a diagram showing the data structure of a pattern table.

[0063] [ Fig.45 ] is a flowchart showing the processing actions.

[0064] [ Fig.46 ] is a block diagram showing the functional structure of the control PC 23 of a modified example of implementation mode 2.

[0065] [ Fig.47 ] is a flowchart showing the processing actions of a modified example of implementation mode 2.

[0066] [ Fig.48 ] is a flowchart showing the processing actions of a modified example of implementation mode 2.

[0067] [ Fig.49 ] is a diagram for illustrating a variation of the drawing pattern of embodiment 2.

[0068] [ Fig.50 ] is a flowchart showing the operation of a modified example of laser processing (xyθ position deviation). [ Fig.51 ] is a flowchart showing the operation of a modified example of laser processing (xyθ position deviation). [ Fig.52 ] is a flow chart showing the operation of a modified example of laser processing (z-direction step difference). [ Fig.53 ] is a flow chart showing the operation of a modified example of laser processing (z-direction step difference). [ Fig.54 ] is a diagram showing the system structure of the measurement system 1000.

[0069] [ Fig.55 ] is a diagram for illustrating the state of the measurement object 1002 placed on the tray 1003.

[0070] [ Fig.56 ] is a flow chart illustrating the actions of the measurement program.

[0071] [ Fig.57 ] is image data showing the result of the first spot analysis processing.

[0072] [ Fig.58 ] is a diagram used to illustrate the setting of the mask area.

[0073] [ Fig.59 ] is image data showing the result of the second spot analysis processing. DETAILED DESCRIPTION

[0074] <Implementation Method 1>

[0075] (1) Overall structure of laser processing device 1

[0076] Figure 1 is an external view showing the structure of the laser processing device 1, Figure 2 It is a schematic diagram showing the functional structure of the laser processing device 1.

[0077] like Figure 1 and Figure 2 As shown, the laser processing apparatus 1 includes a first oscillator 2 (blue semiconductor laser) for oscillating a first laser L1, a second oscillator 3 (IR fiber laser) for oscillating a second laser L2, a hybrid galvanometer scanner 10 for aligning the optical axes of the first laser L1 and the second laser L2 and for displacing the irradiation positions of the first laser L1 and the second laser L2 relative to the workpiece W, an image processing unit 9 for capturing an image of the workpiece W and analyzing the arrangement of each rectangular line, a workpiece placing table 11 on which the workpiece W can be placed and moved in three-dimensional directions (x, y, z) and in a rotation direction (θ) around the z-axis, a fixing fixture 15 for fixing the workpiece W on the workpiece placing table 11, a control PC (personal computer) 12 for controlling the entire laser processing apparatus 1, a PLC (programmable logic controller) 13 for controlling each device in cooperation with the control PC 12, and a laser controller 14 for controlling the operation of the first oscillator 2 and the second oscillator 3.

[0078] The image processing unit 9 is composed of an illumination device 101, an imaging device 102, and a controller 103. The controller 103 is built in Figure 1 The control panel 100 is provided with a computer for controlling the laser processing device 1. Specifically, in addition to the controller 103 of the image processing unit 9, a PLC 13 and a laser controller 14 are provided. The workpiece mounting table 11 is composed of a base 11a, an x-axis table 11x as a mechanism for moving the workpiece W in the x-axis direction, a y-axis table 11y as a mechanism for moving the workpiece W in the y-axis direction, a θ-axis table 11θ as a mechanism for rotating the workpiece W around the z-axis, and a z-axis table 11z as a mechanism for relatively moving the workpiece W and the hybrid galvanometer scanner 10 in the z-axis direction.

[0079] (2) About laser

[0080] The first laser L1 and the second laser L2 oscillated from the first oscillator 2 and the second oscillator 3 are incident on the hybrid galvanometer scanner 10 through optical fiber transmission. The first laser L1 and the second laser L2 are overlapped by the hybrid galvanometer scanner 10 so that their optical axes are aligned. The overlapped L1 and L2 are reduced to a predetermined diameter and then irradiated onto the opposite workpiece W. In this way, in the laser processing device 1, the workpiece W is irradiated with the two lasers L1 and L2 to perform welding.

[0081] As the first laser L1, a blue semiconductor laser connected to a multimode optical fiber is used. The wavelength of the first laser L1 only needs to be 300 to 600 nm, and a green laser can be used instead of the blue laser. In addition, the output power of the first laser L1 is preferably 500 W to 3 kW, and 600 W is taken as an example in this embodiment.

[0082] As the second laser L2, a near-infrared single-mode fiber laser with a wavelength of 780nm to 1100nm is used. That is, the wavelengths of the first laser L1 and the second laser L2 are different from each other, and the wavelength of the first laser L1 is shorter than the wavelength of the second laser L2. The output power of the second laser L2 is preferably 500W to 2kW, and 1.5kW is taken as an example in this embodiment.

[0083] In the present embodiment, the first laser L1 uses multimode, and the second laser L2 uses single mode. The second laser L2 is a point light with a smaller focusing diameter than the first laser L1. Therefore, by using a single-mode fiber laser as the second oscillator 3, the second laser L2 with a small beam diameter and high peak energy intensity can be effectively generated.

[0084] (3) About the hybrid galvanometer scanner 10

[0085] Next, the hybrid current scanner 10 will be described in detail.

[0086] Figures 3 to 5 The hybrid galvanometer scanner shown comprises: a combining section 4 for overlapping the laser lights L1 and L2 provided by the first oscillator 2 and the second oscillator 3 on the same optical axis; a focusing shifting section 6 located downstream of the combining section 4 for adjusting the focal lengths of the laser lights L1 and L2 overlapping on the same optical axis; and a galvanometer scanning section 8 located downstream of the focusing shifting section 6 for shifting the optical axis direction of the laser lights L1 and L2 toward the workpiece W.

[0087] like Figure 3 As shown, the combining unit 4 includes, for example: lenses (collimating lenses, etc.) 31, 32 for collimating the lasers L1, L2 supplied from the first oscillator 2 and the second oscillator 3, respectively; and reflectors (including beam splitters, half mirrors, synthesizers, etc.) 33, 34 required to make the optical axes of the lasers L1, L2 passing through the lenses 31, 32 consistent. Of course, the combining unit 4 may also include optical elements, optical fibers, etc. other than those described above. In addition, in the combining unit 4, three or more lasers with different wavelengths may be superimposed.

[0088] like Figure 4As shown, the focus shifting unit 6 includes: a lens (concave lens, especially a biconcave lens, etc.) 41 for expanding the diameter of the laser light L1 and L2 overlapped in the combining unit 4; and lenses (a plurality of convex lenses, especially a plano-convex lens used as a collimating lens or a focusing lens, etc.) 42 and 43 for reducing the diameter of the laser light L1 and L2 passing through the lens 41. Of course, the focus shifting unit 6 may also include optical elements, optical fibers, etc. other than those described above.

[0089] The focus shift unit 6 variably adjusts the focal length F of the laser light L1 and L2 brought from the combining unit 4. Figure 4 In the example shown, in order to variably adjust the relative distance D of the concave lens 41 and the convex lens 42 along the laser L1 and L2 axes, at least one of the concave lens 41 and / or the convex lens 42 is supported by a linear motor carriage and other appropriate drive mechanisms and can move forward and backward along the optical axis. In addition, the focusing lens 43 of the terminal may not move forward and backward along the optical axis.

[0090] like Figure 4 As shown in (a) in FIG. 1 , the smaller the distance D between the concave lens 41 and the convex lens 42, the longer the focal length F of the lasers L1 and L2 passing through the lenses 41, 42, and 43 of the focus shift unit 6. That is, the focal points of the lasers L1 and L2 are farther from the lens 43 at the end of the focus shift unit 6.

[0091] On the contrary, Figure 4 As shown in (B) in FIG. 1 , the greater the distance D between the concave lens 41 and the convex lens 42, the shorter the focal length F of the lasers L1 and L2 passing through the lenses 41, 42, and 43 of the focus shift unit 6. That is, the focal points of the lasers L1 and L2 are close to the lens 43 at the end of the focus shift unit 6.

[0092] In addition, as a universal physical law, chromatic aberration inevitably occurs in lenses 41, 42, and 43 (because the refractive index of light depends on the wavelength of the light). Therefore, when an attempt is made to irradiate a laser beam that overlaps multiple laser beams of different wavelengths onto the workpiece W, the irradiation position of a laser beam of a certain wavelength and the irradiation position of laser beams of other wavelengths that should be overlapped thereon will deviate on the workpiece. This deviation may result in the inability to obtain the desired laser processing or processing result. Therefore, in practice, the focus of the overlapping laser beam L1 is aligned with the focus of the laser beam L2 by adjusting the position of the lens 31 and / or lens 32 through which the laser beams L1 and L2 output from the first oscillator 2 and the second oscillator 3 pass.

[0093] like Figure 3 and 5As shown, the galvanometer scanning unit 8 is known, and the mirrors 81 and 83 that reflect the laser light L1 and L2 brought from the focus shift unit 6 are rotated via the driving mechanism 82 and 84 of the servo motor, stepping motor, etc. In short, the galvanometer scanning unit 8 can change the optical axis direction of the laser light L1 and L2 reflected by the mirrors 81 and 83. The galvanometer scanning unit 8 of this embodiment includes X-axis galvanometer scanners 83 and 84 that change the optical axis of the laser light L1 and L2 toward the workpiece W along the X-axis direction on the workpiece W, and Y-axis galvanometer scanners 81 and 82 that change the optical axis of the laser light L1 and L2 along the Y-axis direction on the workpiece W. By scanning the laser light L1 and L2 in the XY two-dimensional direction relative to the workpiece W, the irradiation position of the laser light L1 and L2 on the workpiece W can be two-dimensionally controlled.

[0094] As a feature of the hybrid galvanometer scanner 10 of the present embodiment, it is possible to cite the synchronization of adjustment of the focal length F of the focus shift unit 6 and displacement of the galvanometer scanner unit 8 in the optical axis direction.

[0095] The closer the angle θ of the optical axes of the laser beams L1 and L2 passing through the mirrors 81 and 83 of the galvanometer scanner 8 to the workpiece W is to verticality, the shorter the optical path length from the mirror 83 to the workpiece W is. Therefore, the closer the angle θ of the laser beams L1 and L2 to verticality (90°), the more synchronously the focus shift unit 6 and the galvanometer scanner 8 are controlled to shorten the focal length F represented by the focus shift unit 6.

[0096] On the contrary, as the angle θ of the optical axes of the laser beams L1 and L2 passing through the mirrors 81 and 83 of the current scanning unit 8 is tilted from the vertical direction with respect to the workpiece W, the optical path length from the mirror 83 to the workpiece W becomes longer. Therefore, as the angle θ of the laser beam L1 and L2 axes with respect to the workpiece W is tilted more (away from 90°), the focus shift unit 6 and the galvanometer scanning unit 8 are synchronously controlled so that the focal length F reflected by the focus shift unit 6 becomes longer.

[0097] By synchronously controlling the lenses 41, 42 of the focus moving unit 6 and the mirrors 81, 83 of the galvanometer scanning unit 8, the lasers L1, L2 can be irradiated to any part of the workpiece W, and the focus of the lasers L1, L2 can be accurately aligned with the desired processing surface of the workpiece W.

[0098] It is preferred that there is no lens (fθ lens, etc.) through which the lasers L1 and L2 pass between the reflectors 81 and 83 of the galvanometer scanning unit 8 and the workpiece W. Thus, the problem of chromatic aberration caused when the lasers L1 and L2 pass through the lens when the direction of the optical axis is manipulated by the galvanometer scanning unit 8 can be reliably avoided. That is, there is no deviation between the position where the laser L1 of a certain wavelength irradiates the workpiece W and the position where the laser L2 overlapping with the laser L1 irradiates the workpiece W. Therefore, the desired laser processing or processing result can be obtained.

[0099] However, if chromatic aberration occurs only to a negligible degree in the irradiation positions of the laser beams L1 and L2 , it is not difficult to interpose some kind of lens that transmits the laser beams L1 and L2 between the reflective mirrors 81 and 83 of the galvanometer scanner 8 and the workpiece W.

[0100] The hybrid galvanometer scanner used in this embodiment is not limited to the above-described structure. The biconcave lens 41, the collimating lens 42, and the condenser lens 43 as the elements of the focus shift unit 6 are pushed and located downstream of the reflective mirrors 33 and 34 as the elements of the combination unit 4, but the arrangement of these optical elements 33, 34, 41, 42, 43 is not limited to Figure 3 shown.

[0101] Figure 6 A hybrid galvanometer scanner 10a is shown as a modified example. In the hybrid galvanometer scanner 10a, a biconcave lens 41 and a collimator lens 42 are arranged on the optical axis of the laser light L1 output from the first oscillator 2 and the optical axis of the laser light L2 output from the second oscillator 3. In short, there are two biconcave lenses 41 and two collimator lenses 42.

[0102] Then, the laser light L1 and the laser light L2 having passed through the biconcave lens 41 and the collimator lens 42 are superimposed on each other via the reflection mirrors 33 and 34 as elements of the combining unit 4 , and finally condensed by the condensing lens 43 , and input to the galvanometer scanning unit 8 .

[0103] Figure 6 The hybrid galvanometer scanner 10a shown is also Figure 3 Similar to the hybrid galvanometer scanner 10, the relative distance D between the concave lens 41 and the convex lens 42 along the laser L1 and L2 axes can be variably adjusted. Therefore, at least one of the concave lens 41 and / or the convex lens 42 on each laser L1 and L2 axis is supported by a linear motor carriage and other appropriate drive mechanisms, and can be moved forward and backward along the optical axis.

[0104] For example, the concave lens 41 on the optical axis L1 and the concave lens 41 on the optical axis L2 are controlled simultaneously by a single axis, so that both of these concave lenses 41 can move forward and backward along the optical axis. The positions of the convex lenses 42 on the optical axes L1 and L2 along the optical axis are pre-adjusted according to the wavelengths of the lasers L1 and L2.

[0105] The above-mentioned adjustment of the relative distance D, in other words, is of course to synchronize the adjustment of the focal length F by the focus shift unit 6 and the displacement in the optical axis direction by the galvanometer scanning unit 8 .

[0106] exist Figure 3 In the example shown, laser beams L1 and L2 having different wavelengths are overlapped by the reflectors 33 and 34 of the combining unit 4, and then the focal lengths thereof are adjusted by the lenses 41, 42 and 43 of the focus shift unit 6. Figure 6 In the modified example shown, after adjusting the focal length of each laser light L1, L2 by the lenses 41, 42 of the focus shift unit 6, these laser lights L1, L2 are overlapped by the mirrors 33, 34 of the combining unit 4. Thus, it is possible to appropriately avoid chromatic aberration in the lenses 41, 42, and to irradiate the laser lights L1, L2 to a desired irradiation position on the workpiece W with higher accuracy using the galvanometer scanner 5.

[0107] As a further modification, Figure 7 1 shows a hybrid galvanometer scanner 10b. In this modification, a biconcave lens 41, a collimating lens 42, and a focusing lens 43 are arranged on the optical axis of the laser light L1 output from the first oscillator 2 and the optical axis of the laser light L2 output from the second oscillator 3. In short, there are two biconcave lenses 41, two collimating lenses 42, and two focusing lenses 43.

[0108] Then, the laser light L1 and the laser light L2 that have passed through the biconcave lens 41 , the collimator lens 42 , and the condenser lens 43 are superimposed on each other via the reflection mirrors 33 and 34 that are elements of the combining unit 4 , and are then input to the galvanometer scanning unit 8 .

[0109] Figure 7 The hybrid galvanometer scanner 10b shown is also Figure 3 Similar to the hybrid galvanometer scanner 10, the relative distance D between the concave lens 41 and the convex lens 42 along the laser L1 and L2 axes can be variably adjusted. Therefore, at least one of the concave lens 41 and / or the convex lens 42 on each laser L1 and L2 axis is supported by a linear motor carriage and other appropriate drive mechanisms, and can be moved forward and backward along the optical axis.

[0110] For example, the concave lens 41 on the optical axis L1 and the concave lens 41 on the optical axis L2 are controlled simultaneously by a single axis, so that both of these concave lenses 41 can move forward and backward along the optical axis. The positions of the convex lenses 42 on the optical axes L1 and L2 along the optical axis are pre-adjusted according to the wavelengths of the lasers L1 and L2.

[0111] The above-mentioned adjustment of the relative distance D, in other words, is of course to synchronize the adjustment of the focal length F by the focus shift unit 6 and the displacement in the optical axis direction by the galvanometer scanning unit 8 .

[0112] exist Figure 7 In the modified example shown, after adjusting the focal length of each laser light L1, L2 by the lenses 41, 42, 43 of the focus shift unit 6, these laser lights L1, L2 are overlapped by the mirrors 33, 34 of the combining unit 4. Thus, it is possible to appropriately avoid chromatic aberration in the lenses 41, 42, 43, and to irradiate the laser lights L1, L2 to a desired irradiation position on the workpiece W with higher accuracy using the galvanometer scanning unit 8.

[0113] (4) Description of workpiece W

[0114] Next, use Figures 8 to 10 The workpiece W to be welded will be described. Figure 8 1 is a perspective view showing a schematic structure of a stator 50 as a stator of a motor of an electric vehicle or the like. As shown in the figure, the stator 50 has a stator core 51 of a substantially cylindrical shape and a plurality of rectangular wires (segmented coils) 52. The rectangular wires 52 are conductors (electric wires) having a rectangular cross section. Usually, the rectangular wires 52 use pure copper wires, but can also be made of a metal material having high conductivity, such as an alloy with copper as the main component, an alloy composed of copper and aluminum. The end of each rectangular wire 52 protrudes from the upper end of the stator core 51, and the laser processing device 1 laser welds the ends of two adjacent rectangular wires 52 in the radial direction of the stator core 51.

[0115] In the welding process of the front ends of the rectangular wires 52, the insulating coating on the front end side is peeled off, and the front ends of the two corresponding rectangular wires are butted. Then, the laser is irradiated to the butted end faces. At this time, due to the deviation of the processing accuracy of each rectangular wire, the mechanical accuracy of the fixing jig 15, the insertion into the groove 54, etc., a gap (gap, space) or positional deviation may occur when the front ends of the two rectangular wires are butted.

[0116] exist Fig. 9 In the example (a), there is a gap between the two rectangular lines 52. Fig. 9 In the example (b), the two rectangular lines 52 are offset in the y-axis direction. Fig. 9 In the example of (c), the two rectangular wires 52 have a gap in the x-axis direction, are offset in the y-axis direction, and are further rotated in the θ direction.

[0117] If there is a gap (gap, void) or a large positional offset between the corresponding two rectangular lines 52, the laser may be transmitted through the gap or offset position, and the laser may be irradiated to the lower part of the rectangular conductor, causing carbonization and poor insulation. In addition, even if the laser is not transmitted due to the positional offset in the y-axis direction, if the laser is irradiated across the two rectangular lines 52 without considering any positional offset, the molten part may be offset or tilted, and the welding strength may also be reduced.

[0118] In addition, if Fig.10 As shown in FIG. 1 , when the front ends of the two rectangular wires 52 are butted, a step difference Δz due to deviation in the height direction (z direction) may occur. A certain gap (gap, space) Δxy may occur due to the thickness of the insulating coating. In the following, the step difference amount in the z direction of the two rectangular wires 52 may be recorded as Δz, and the gap amount in the xy plane may be recorded as Δxy.

[0119] Thus, when there is a step difference in the z-axis direction between the corresponding rectangular lines, if the laser crosses the step difference, a large amount of sputtering may sometimes occur. In addition, if the laser is scanned uniformly across the left and right rectangular lines without considering the step difference, the height of the molten part may be different on the left and right, which may cause a loss of balance and reduce the welding strength.

[0120] Therefore, the laser processing device 1 of this embodiment can perform welding processing while suppressing the occurrence of laser transmission and reduction in welding strength even when a gap, positional deviation, or step difference in the z-axis direction occurs between two corresponding rectangular lines 52 .

[0121] (5) Image Processing Unit 9

[0122] In the welding of stator coils, it is necessary to accurately measure the position of the rectangular wire so that the laser can be properly irradiated on the rectangular wire of several millimeters. Therefore, in the laser processing device 1, the center position and height of multiple rectangular wires 52 relative to the front end are measured by image analysis of the image processing unit 9. In addition, when the center position is measured by image analysis, if the rectangular wires are close to or abut against each other, the boundary line becomes unclear and it is difficult to determine the position of each rectangular wire with high precision. Therefore, the image processing unit 9 of this embodiment can measure the center position of each rectangular wire 52 with high precision even when the rectangular wires are set to be close to or abut against each other. The measurement method is described in detail below.

[0123] like Fig.11As shown, the image processing unit 9 includes: an illumination device 101 for applying illumination light to the workpiece W; a camera device 102 for photographing the workpiece W in a state where the workpiece W is illuminated by the illumination device 101; and a controller 103, which uses the image data captured by the control unit 102 to measure the center position and height of each right angle line 52 included in the workpiece W.

[0124] The lighting device 101 and the camera device 102 are lighting devices and three-dimensional cameras suitable for the pattern projection method. The lighting device 101 projects multiple stripe patterns from multiple different directions onto the workpiece W, and the camera device 102 receives the reflected light using an image sensor such as a CMOS. The controller 103 generates a three-dimensional image by analyzing the changes in the patterns of the projected light and the reflected light.

[0125] like Fig.11 As shown, the controller 103 includes a memory 104 and a processor 105. A measurement program 111 and a threshold value 112 are pre-stored in the memory 104. The threshold value 112 may be included in the measurement program 111. In addition, the memory 104 stores a coordinate table 113 generated by the processor 105. The processor 105 measures the center positions and heights of all the rectangular lines 52 included in the workpiece W by executing the measurement program 111, and generates the coordinate table 113 (CSV data).

[0126] Here, use Fig.12 and Fig.13 , the center position and height measured by the controller 103 are described. Fig.12 In the example of , the two rectangular lines 52 are offset in the x-axis direction, the y-axis direction, and the θ direction. Fig.13 In the example, the case where two rectangular lines 52 are offset in the x-axis direction and there is a step difference in the z-axis direction is described as an example.

[0127] In addition, for convenience of description, one of the rectangular wires 52 is described as “A pin”, and the other rectangular wire 52 is described as “B pin”.

[0128] The controller 103 measures the coordinates (x, y, z, θ) of the center of the welding surface 52a for pin A. The coordinates are recorded as "pin A coordinates". Similarly, for pin B, the coordinates (x, y, z, θ) of the center of the welding surface 52a are measured. The coordinates are recorded as "pin B coordinates". In addition, the controller 103 calculates the coordinates (x, y, z, θ) of the middle point between pin A and pin B. The coordinates are recorded as "AB pin coordinates". Here, as an example, the origin (reference point) of the xyz orthogonal coordinate system is set as the center point of the upper surface of the workpiece mounting table 11 on which the workpiece W is placed. In addition, θ is the angle around the z-axis on the xy plane. In addition, θ can be measured by image processing, but if the structure of the stator 50 to be welded is known, a value derived from the structure of the stator 50 can be used instead of the measurement by image processing.

[0129] The controller 103 measures the coordinate values ​​of each rectangular line and the coordinate value of the center point for each pair of welding targets for all rectangular lines 52 included in the stator 50 , and then records the measured results in a coordinate table 113 , which is stored in the memory 104 .

[0130] (6) About Control PC12

[0131] like Fig.14 As shown, the control PC 12 is composed of a control unit 201 , a storage unit 202 , an input unit 203 , a communication unit 204 , and a display unit 205 .

[0132] Specifically, the control PC 12 is a computer system having hardware resources such as a CPU (central processing unit), a ROM (read only memory), a RAM (random access memory), a HDD (hard disk drive), an SSD (solid state drive), a display unit, a communication interface, and input devices such as a keyboard or a mouse. In welding processing using a galvanometer scanner, the control PC is sometimes referred to as a "galvanometer PC".

[0133] The control unit 201 is composed of a CPU, a RAM as a working memory, and the like.

[0134] The storage unit 202 is a so-called auxiliary storage device, and is composed of a nonvolatile memory such as an HDD, an SSD, a ROM (Read Only Memory), or a flash memory.

[0135] The storage unit 202 stores various data such as a computer program for controlling the laser processing device 1 , various laser parameters input via the input unit 203 , and processing pattern data 110 used in welding processing.

[0136] The control unit 201 loads the computer program stored in the storage unit 202 into the RAM as a working memory and executes it, thereby controlling the first oscillator 2, the second oscillator 3, the hybrid galvanometer scanner 10, the PLC 13, the laser controller 14, etc., to perform welding processing of the workpiece W. In addition, the laser parameters stored in the storage unit 202 are the laser output used in the first oscillator 2 and the second oscillator 3, the processing rate (laser irradiation time), the marking speed, the acceleration time, the deceleration time, etc.

[0137] The input unit 203 also includes input devices such as a keyboard, a mouse, and various switches that accept user operations, and a device that inputs data by connecting a removable recording medium such as a USB memory or an SD memory card. The data input via the input unit 203 is stored in the storage unit 202.

[0138] The communication unit 204 communicates information with external devices (such as the image processing unit 9 , the hybrid galvanometer scanner 10 , the PLC 13 , and the laser controller 14 ) connected wirelessly or by wire.

[0139] The display unit 205 includes a display unit, a video codec, a GPU (graphics processing unit), a memory for screen data, etc., generates a UI screen, etc., and displays it on the display unit. The user can also input various parameters and the like to be instructed to the laser controller 14 through the input unit 203 while the display unit 205 displays the UI screen.

[0140] (7) Overall action of laser processing

[0141] Next, refer to Fig.15 The operation of the laser processing device 1 will be described.

[0142] First, a workpiece W is placed on the workpiece mounting table 11 (step S11). The control PC 12 sets laser parameters (laser output, acceleration time, deceleration time, etc.) for each oscillator 2, 3 via the laser controller 14 (step S12). The user operates the input unit 203 of the control PC 12 to input the processing pattern data 110, and the control PC 12 registers the processing pattern data 110 in the storage unit 202 (step S13). Fig.16 The registration screen 150 is shown as an example of a UI screen when the user inputs laser parameters or processing pattern data. The registration screen 150 is a UI screen for registering laser parameters used in the first oscillator 2 and the second oscillator 3, and processing pattern data used in the hybrid galvanometer scanner 10 during laser irradiation in the third step described later.

[0143] As an example, the registration screen 150 includes a job list 151, a processing point list 152, a processed image 153, a laser parameter input unit 154, and a registration button 155. For example, if "straight line" is selected in the job list 151, the xy coordinate values ​​of the processing points are added to the processing point list 152, and a graph connecting the processing points with straight lines is displayed on the processed image 153. When the user selects the registration button 155 in this state, the processed graphic data 110 displayed on the processed image 153 is registered in the storage unit 102. In addition, the processed graphic data 110 is necessary information for the hybrid galvanometer scanner 10 to scan the laser according to the processed image.

[0144] Here, in the present embodiment, welding is performed by subjecting two rectangular wires 52 having a gap or positional deviation to laser irradiation in three steps consisting of a first step, a second step, and a third step.

[0145] The processing of step S11, step S12, and step S13 does not necessarily have to be performed in this order.

[0146] The workpiece mounting table 11 carrying the workpiece W is moved to place the workpiece W directly below the image processing unit 9 (step S14). Next, the image processing unit 9 captures an image of the workpiece W (step S13). Specifically, the lighting device 101 projects a plurality of stripe patterns onto the workpiece W from a plurality of different directions using a pattern projection method, the camera device 102 captures each image, and the images captured by the controller 103 are synthesized to calculate a 3D shape (step S14).

[0147] Next, the controller 103 of the image processing unit 9 performs a measurement process of the center position and height of each rectangular line 52 (step S17), and generates CSV data (coordinate table 113) recording the measurement results. The image processing unit 9 sends the CSV data (coordinate table 113) recording the measurement results to the control PC 12 (step S18). The transmission of the CSV data from the image processing unit 9 to the control PC 12 can be sent via a wireless or wired network, or can be sent via a portable recording medium such as a USB memory or an SD memory card.

[0148] Next, the PC 12 is controlled to perform laser processing (step S19). In the present embodiment, the scanning movable range of the hybrid galvanometer scanner 10 is set to cover the entire size of the workpiece W. However, in the case of welding a motor that is larger than the scanning operation range of the galvanometer scanner, the laser processing device 1 can perform welding while rotating the workpiece W using the θ-axis table 110 of the workpiece mounting table 11. Depending on the size of the motor, welding is sometimes performed while rotating the motor in 1 / 4 increments, and sometimes while rotating the motor in 1 / 8 increments.

[0149] (8) Measurement processing actions

[0150] Here, as a preparation for welding, the operation of the measurement process performed by the image processing unit 9 will be described. Fig.17 and Fig.18 is a flowchart showing the operation of the measurement processing of the image processing unit 9, and is also Fig.15 The details of step S17 in FIG. 1 are given in detail. In practice, the processor 105 executes the measurement program 111 stored in the memory 104 of the controller 103 to perform the operation.

[0151] The image processing unit 9 repeats steps S21 to S36 for each measurement range of the workpiece W. In this embodiment, as an example of a measurement range, Fig.19 As shown, a plurality of rectangular lines 52 (four rectangular lines 52 in this example) arranged in the radial direction of the stator 50 are defined as one measurement range.

[0152] The image processing unit 9 performs the first spot analysis process (step S22). Spot analysis is a type of image analysis that performs binarization processing on each pixel contained in the target image data and uses the binarized image data to perform various analyses and measurements. Fig. 20 As shown, the first spot analysis process performs binarization processing on the cross-sectional shape of the rectangular line 52 included in the measurement range when cut along the xy plane 57 .

[0153] The xy plane 57 can be set at any height, but in order to perform laser irradiation toward the end surface of the rectangular wire 52, the xy plane 57 must be set at least on the front end side of the stripped insulating coating portion 58. Fig.19 As shown, the image processing unit 9 marks (numbers) the rectangular lines 52. As an example, the marking is performed in a clockwise order from the 0 degree column. In addition, in the radial direction, the marking is performed sequentially from the center of the stator 50 to the outside. Here, as an example, a common numerical value is marked on a pair of rectangular lines 52 to be welded. The pair of rectangular lines 52 marked with the common numerical value are marked as "A" on the inside in the radial direction and "B" on the outside in the radial direction.

[0154] Fig.21 (a) shows image data 120a after the measurement range is binarized. The image data after binarization is actually expressed in two grayscales, white and black, but in this embodiment, for the sake of convenience, black is recorded in a hatching pattern. Fig.21 (a) to 21(c) to illustrate the following processing.

[0155] The image data 120a includes a spot B21, a spot B22, and a spot B23. The controller 103 of the image processing unit 9 repeats steps S24 to S33 for each spot included in the image data 120a. First, the controller 103 measures the center coordinates (x, y) of the target spot (step S25), and further measures the area (step S26). Then, the measured area is compared with the pre-stored threshold 112. Thus, it is determined whether the rectangular lines are connected to each other. The threshold 112 can be set according to the cross-sectional area of ​​the rectangular line 52, and as an example, it is set to be greater than 1.5 times and less than 2.0 times the cross-sectional area.

[0156] In the present embodiment, the threshold value may be a rewritable value and may be rewritten according to the properties such as the shape or material of the object to be measured or the physical quantity or value to be measured.

[0157] If the area of ​​the spot is less than the threshold value ("No" in step S27), the process proceeds to step S32. If the area of ​​the spot is greater than the threshold value ("Yes" in step S27), a mask region is configured on the target spot and the spot is segmented (step S28). Fig. 20 In the case of spot B23 (center position P23) shown in (a), if Fig.21 As shown in (b), a mask area of ​​an elongated shape including the center position P23 is arranged on the image data. The mask area is an area that is not recognized in image processing. In this embodiment, the gap, step difference, position deviation, etc. are calculated by image processing, and laser irradiation is performed taking these into consideration, but the arrangement of each rectangular line 52 itself is pre-positioned. Therefore, the controller 103 calculates and arranges the position of the mask area according to the position of the rectangular line 52 corresponding to the target spot. In addition, the line width of the mask area is sufficient as long as it is about 1 to 2 pixels. Fig.21 (b) shows the image data 120b after the mask region is arranged.

[0158] Next, the controller 103 performs a second spot analysis process on the image data 120b (step S29). Fig.21 In the image data 120c of (c), the spot B23 is divided into the spot B24 and the spot B25. The controller 103 marks the divided spots (step S30). Thus, all the rectangular lines 52 can be identified by the numerical values ​​from 1 to 48 and the symbols A and B. In addition, the controller 103 measures the center coordinates of the spots B23 and B24 (step S31).

[0159] Next, the controller 103 measures the average height of the rectangular line 52 for any range including the center position obtained as a result of the spot analysis process (step S32). Fig. 22 As shown in FIG. 1 , the average height of the circle (R21, R22, R23) centered at the center position (P21, P22, P23) of each rectangular line 52 is measured. The measured average height is set as the height (z) of the rectangular line 52. The controller 103 may also measure the height of a point at the center position of each rectangular line 52, but as shown in FIG. Fig. 22 As shown, the measurement error can be absorbed by calculating the average height of a predetermined range.

[0160] Next, the controller 103 calculates the coordinates (x, y, z, θ) of the middle point of the two corresponding rectangular lines 52 (step S34). Furthermore, the controller 103 calculates the z-axis offset value (step S35) when there is a step difference between the two corresponding rectangular lines 52. The offset value will be described later.

[0161] When the controller 103 completes the measurement of the center position and height (x, y, z, θ) of all rectangular lines 52 and the coordinate values ​​and height (x, y, z, θ) of the intermediate points, a coordinate table 113 recording the measurement results is generated (step S37). Specifically, the coordinate table 113 generated here is CSV data. Fig.21 It is a diagram showing the data structure of the coordinate table 113.

[0162] In this way, the controller 103 performs the spot analysis process twice, and thus can accurately measure the center position of each rectangular line 52 even when the rectangular lines are in contact with each other.

[0163] (9) Laser processing

[0164] Here, the laser processing according to this embodiment will be described in detail.

[0165] (9-1) Three basic steps

[0166] First, three basic steps of welding using the laser processing device 1 will be described.

[0167] In the butt welding of the right angle wire by the laser processing device 1 of this embodiment, a welding method is provided in which the laser does not penetrate through the gap even if there is a gap, and the processing time can be shortened while maintaining good welding quality and welding strength. Specifically, the laser processing device 1 performs a welding method consisting of three steps, namely, the first step, the second step, and the third step.

[0168] use Fig.24, a welding method consisting of three steps is described. Here, as an example, a case where a gap 53 of 0.5 mm is left when two rectangular lines 52 with a size of 2.0 mm×2.5 mm on the end faces are butted is described. In addition, if the focusing diameter of the first laser L1 is set to d1 and the focusing diameter of the second laser L2 is set to d2, then d1=1050μm, d2=40μm.

[0169] Fig.24 (a) shows the irradiation trajectory 11 of the first laser L1 and the second laser L2 in the first step. In the first step, the end surface 52a of the rectangular line 52 on the left side of the paper is reciprocated in the y-axis direction in a substantially straight line from the center O of the workpiece W (this is the center of the workpiece W including the gap 53) to a position 1.0 mm in the x-axis direction. The irradiation width of the reciprocating irradiation is 1.0 mm in the y-axis direction. In the first step, the first laser L1 and the second laser L2 are irradiated at a speed of 500 mm / s.

[0170] Fig.24 (b) shows the irradiation trajectory 12 of the first laser L1 and the second laser L2 in the second step. In the second step, the end surface 52a of the rectangular line 52 on the right side of the paper is reciprocated in the y-axis direction in a substantially straight line from the center O of the workpiece W to a position 1.0 mm in the x-axis direction. The irradiation width of the reciprocating irradiation is 1.0 mm in the y-axis direction. In the second step, the first laser L1 and the second laser L2 are irradiated at a speed of 500 mm / s as in the first step.

[0171] Fig.24 (c) shows the irradiation trajectory 13 of the first laser L1 and the second laser L2 in step 3. The trajectory 13 is an ellipse with a short diameter of 1.2 mm and a long diameter of 2.4 mm, and in step 3, elliptical rotation irradiation is performed across the left and right rectangular conductors 52. In step 3, the first laser L1 and the second laser L2 are irradiated at a speed of 1000 mm / s.

[0172] In each of the first step, the second step, and the third step, if the temperature of the welding surface rises sharply, sputtering may occur. Therefore, the second laser L2 with high power density may be controlled to start irradiation at a low output, and the power may be gradually increased until the specified output is reached. In this embodiment, the second laser L2 is controlled in each step so that the output increases from 0 to 1.5 kW within 5.0 ms.

[0173] use Fig.25 This section will explain the changes in the weld surface caused by welding in three steps in this way. Fig.25Here, for the sake of convenience, the rectangular line 52 on the left side of the paper is described as "A", and the rectangular line 52 on the right side of the paper is described as "B".

[0174] (a) The irradiation of the first step is started on the rectangular line A to melt the end surface 52a.

[0175] (b) The corner of the end face 52a of the rectangular line A is melted and rounded, forming the first molten portion 54. The laser processing device 1 performs the irradiation of the first step until the first molten portion 54 falls off (as an example, the irradiation stops after 68 milliseconds). Here, "falling off" means that a part of the first molten portion 54 formed on the end face 52a enters the gap 53 and begins to flow downward.

[0176] (c) Next, the second step of irradiation is started on the rectangular wire B, and the end surface 52a of the rectangular wire B is melted.

[0177] (d) The corner of the end face 52a of the rectangular line B is melted and rounded, forming a second molten portion 55. The laser processing device 1 performs the irradiation of the second step until the second molten portion 55 falls off (for example, the irradiation is stopped after 68 milliseconds).

[0178] (e) The first molten zone 54 and the second molten zone 55 are connected. Here, since the laser irradiation timings of the rectangular line A and the rectangular line B are different, the molten metal of the rectangular line A may be cooled and solidified when the irradiation of the second step is completed.

[0179] (f) Therefore, after the first molten portion 54 and the second molten portion 55 are combined, the irradiation of the third step is performed, and the rectangular line A is heated again to make the first molten portion and the second molten portion uniform, thereby forming a molten portion 56. The irradiation of the third step may be continued until the molten portion 56 reaches a desired size (for example, the irradiation is stopped after 70 milliseconds).

[0180] Here, if Fig.24 and 25 As shown in FIG. 1 , in the first and second steps, it is preferred to irradiate the laser to a position deviating from the center of each end face 52a, that is, a position closer to the butt joint than the center (a position close to the gap 53). Thus, the time required for the molten parts to be joined together can be shortened. Furthermore, by performing the third step after the two molten parts are joined, damage to the lower part of the rectangular line caused by the laser passing through the gap 53 is suppressed. In addition, by rotating the molten parts joined in the third step and irradiating the laser, the molten parts can be homogenized to form beautiful molten beads that are symmetrical on both sides.

[0181] In addition, the irradiation position and irradiation time in each step basically depend on the size of the welding surface. Therefore, for a workpiece with a known position offset and less step difference, the result of the test irradiation, the optimal value of the irradiation position and the irradiation time are selected, and the optimal value can also be stored in the control PC12. The same is true for the output power of the first laser L1 and the second laser L2. The optimal power of each laser can also be stored in the control PC12. In addition, the number of irradiations can also be used instead of the irradiation time for control.

[0182] In the above description, the trajectory l3 of the laser irradiation in the third step is an ellipse or a circle, but this is only an example, and the trajectory of the laser irradiation in the third step is not limited to an ellipse or a circle.

[0183] Fig.26 FIG. 4 shows a modified example of the laser irradiation trajectory of step 3. Fig.26 As shown in the track 17 of (a), the laser processing device 1 can irradiate the first laser L1 and the second laser L2 across two straight angle lines 52, and perform linear reciprocating irradiation. Fig.26 As shown in the track 18 of (b), the laser processing device 1 can irradiate the first laser L1 and the second laser L2 in a rectangular shape across two rectangular lines 52. Fig.26 As shown in the trajectory 19 of (c), the laser processing device 1 may irradiate the first laser L1 and the second laser L2 in an 8-shape across two rectangular lines 52. In addition to the linear, rectangular, and 8-shape, the irradiation may be performed in a polygonal shape.

[0184] In particular, when irradiation is performed in a rectangular or figure-8 shape, heat energy is easily transferred to the end of the workpiece W, and melting of the welding surface (end surface 52) can be promoted.

[0185] In addition, if Fig. 27 As shown in (a), when the flat angle lines 52 are normally connected to each other, even if the laser is irradiated in an elliptical scanning or circular scanning manner, the laser will not be transmitted downward. Fig. 27 As shown in (b), when the amount of melting at the end (end face 52a) of the workpiece W is small, the surface tension also has an effect, and only the vicinity of the center of the rectangular line 52 is in a bonded state. In this way, when the area of ​​the bonded portion formed in the gap 53 is small, the laser is irradiated in an elliptical scanning or circular scanning manner, and the laser is transmitted downward. Therefore, when the area of ​​the bonded portion is small, it is particularly effective to suppress carbonization or poor insulation of the coating portion caused by the transmission of the laser by performing 8-shaped laser irradiation or linear irradiation.

[0186] Furthermore, in the laser processing device 1, it is not necessary to perform rotational irradiation in the third step. Fig.26As shown in (d), the combined molten parts may be spot-irradiated in the third step. By spot-irradiating the center of the workpiece W with the first laser L1 and the second laser L2, heat is gradually propagated from the center to the end of the workpiece W. In this process, the two molten parts can be homogenized.

[0187] In this way, the third step may be performed only if it is possible to achieve a process for homogenizing the respective molten portions formed in at least the first step and the second step.

[0188] (9-2) Laser processing operation

[0189] Next, refer to Figure 28 to Figure 33 , the details of the laser processing are explained.

[0190] Fig.28 is a flowchart showing the action of laser processing. Fig.15 The details of step S19 are shown in FIG.

[0191] The laser processing device 1 repeatedly performs the processing from step S41 to step S50 for each pair of rectangular lines 52 of the welding target.

[0192] The control unit 201 that controls the PC 12 refers to the coordinate table 113 to acquire a pair of the step amount Δz and the gap amount Δxy that are currently being processed (step S42 ).

[0193] The control unit 201 refers to the processing rate table 1100 stored in the storage unit 102 to acquire the laser irradiation time corresponding to the step difference amount Δz and the gap amount Δxy acquired in step S42 (step S43 ).

[0194] Here, the processing rate table 1100 used in the welding processing by the laser processing device 1 is described. Fig.29 11 is a diagram showing the data structure of the machining rate table 1100. The machining rate table 1100 is a table that describes machining rates (laser irradiation time) [msec] selectable based on the step difference Δz in the z direction and the gap Δxy in the xy plane of a pair of rectangular lines 52 of the welding target.

[0195] For example, when the step difference (Δz) is 0.4 mm and the gap (Δxy) is 0.6 mm, refer to field 1111. Field 1111 contains two numerical values, the upper numerical value (76) represents the laser irradiation time of the high flat angle line 52, and the lower numerical value (58) represents the laser irradiation time of the low flat angle line 52.

[0196] Depend on Fig.29It can be seen that the laser irradiation time of the high flat angle line 52 is set longer than the laser irradiation time of the low flat angle line. This is because in order to make the height of the high flat angle line 52 and the low flat angle line 52 consistent, the melting amount of the high flat angle line 52 increases. Therefore, when the gap amount is the same, the larger the step difference, the longer the laser irradiation time of the high flat angle line 52. In addition, if the gap amount is large, a large amount of melting is required to fill the gap, so the larger the gap amount, the longer the laser irradiation time.

[0197] In this embodiment, the lower rectangular wire 52 is also irradiated with laser light. The irradiation time refers to a state in which the four corners of the end surface 52a of the rectangular wire 52 are melted and a part of the molten metal begins to flow downward into the gap. The time is a value determined by the size of the end surface 52a of the rectangular wire 52, the material composition of the rectangular wire 52, the power of the first oscillator 2 and the second oscillator 3, the laser wavelength, etc., and a value obtained by test processing can be used.

[0198] If the size of the end face 52a is different, the irradiation time recorded in the processing rate table will naturally be different. Fig.29 In FIG. 1 , as an example, the irradiation time when the size of the end surface 52 a is approximately 2.0 [mm]×2.5 [mm] is shown.

[0199] In step S43, the control unit 201 obtains two numerical values ​​listed in the upper and lower rows of the processing rate table 1100. The numerical value listed in the upper row is the irradiation time of the first step, and the numerical value listed in the lower row is the irradiation time of the second step.

[0200] Here, when the value of the step difference Δz obtained in step S42 is inconsistent with the items (0.0 mm, 0.2 mm, 0.4 mm, 0.6 mm, 0.8 mm, 1.0 mm) of the processing speed table 1100, an item closer to the value of the step difference Δz obtained is selected. In addition, when the step difference Δz obtained is an intermediate value, an item with a larger value than the step difference Δz obtained is selected. For example, when the step difference Δz obtained in step S42 is 0.5 mm, the control unit 201 selects the field 1112 of the processing speed table 1100. The same is true for the gap amount Δxy.

[0201] Next, the control unit 201 controlling the PC 12 determines which flat angle line in the current processing is higher (step S44). This determination process is performed by receiving information such as a number for identifying the higher flat angle line from the controller 103 of the image processing unit 9, but the control unit 101 may also perform the determination process by reading the coordinate value from the coordinate table 113. The coordinate table 113 may be stored in the image processing unit 9 or in the control PC 12.

[0202] Next, the laser processing device 1 performs the processing of the first step of irradiating the higher pin with the first laser L1 and the second laser L2 (step S45). Specifically, the laser irradiation time obtained in step S43 is sent from the control unit 201 of the control PC 12 to the laser controller 14, and the laser irradiation time is set for the first oscillator 2 and the second oscillator 3. Furthermore, a control command is sent from the control unit 201 to the hybrid galvanometer scanner 10, and a laser irradiation command is sent from the PLC 13 to the first oscillator 2 and the second oscillator 3 via the laser controller 14. The first oscillator 2 and the second oscillator 3 that receive the laser irradiation command irradiate the first laser L1 and the second laser L2, respectively.

[0203] Fig.30 (a) Fig.31 (a) and Fig.34 (a) is a schematic diagram for explaining the processing of step 1. Fig.30 and Fig.34 In the description, the high flat angle wire 52 is recorded as "B pin", "52 (B)", and the low flat angle wire 52 is recorded as "A pin", "52 (A)".

[0204] The scanning trajectory of the hybrid galvanometer scanner 10 in the first step is linear reciprocating irradiation. When the laser is irradiated at the processing rate (irradiation time) obtained in step S43, the B pin is melted to a height slightly lower than the A pin, forming a molten bead 55b. Here, the first laser L1 and the second laser L2 are linearly reciprocatingly irradiated to a predetermined position of the end face 52a, but it is preferred to linearly reciprocately irradiate to a position of the end face 52a close to the butt surface 52b (position close to the gap).

[0205] Next, the laser processing device 1 performs the processing of the second step of irradiating the lower A pin with the laser beam (step S46). Fig.30 (b) Fig.31 (b) and Fig.34 (b) is a schematic diagram for explaining the process of step 2. In step 2, the welding surface of pin A is irradiated with the first laser L1 and the second laser L2. The scanning trajectory of the hybrid galvanometer scanner 10 at this time is the same as that of step 1, which is a linear reciprocating irradiation. When the laser is irradiated at the processing rate (irradiation time) obtained in step S43, the entire end face 52a of pin A melts, and a molten bead 55a is formed on pin A. Fig.34 As shown in (b), due to the difference in laser irradiation time, the molten bead 55a is smaller than the molten bead 55b.

[0206] In addition, in the second step, the position near the butt joint 52b (position near the gap) on the end face 52a may be irradiated back and forth linearly as in the first step. By irradiating the interior with laser light in this way, the time from the molten portion (molten beads 55a and molten beads 55b) to the bonding can be shortened.

[0207] Next, the control unit 201 that controls the PC 12 corrects the processing pattern data 1100 stored in the storage unit 202 according to the arrangement status of the A pin and the B pin (step S47).

[0208] Fig.32 (a) is a processed image represented by the processed graphic data 1100 stored in the storage unit 102, and is an 8-shaped figure connecting points a, b, c, and d with the origin (0, 0) of the xy orthogonal coordinate system as the center e. Fig.32 (b) is a processed image represented by the processed graphic data obtained by correcting the processed graphic data 110 based on the actual configuration of the A pin and the B pin.

[0209] The correction method of the processing graphic data 1100 is described. The control unit 201 that controls the PC 12 makes the center e of the processing graphic data 1100 consistent with the AB pin coordinate. Then, the processing graphic data 1100 is rotated and stretched along the x-axis direction so that the midpoint of the straight line connecting the point a and the point d of the processing graphic data 1100 is consistent with the A pin coordinate, and the midpoint of the straight line connecting the point c and the point b is consistent with the B pin coordinate. In this way, the corrected processing graphic data is an 8-shaped figure with the AB pin coordinate as the center e, connecting the points a', b', c', and d'. The control unit 201 sends the corrected processing graphic data to the hybrid galvanometer scanner 10.

[0210] Next, before the processing of the third step, the focal position of the laser device 1 is shifted to the height of the B pin before melting (step S48). Then, after the two molten beads 55a and 55b are combined, the laser processing device 1 uses the corrected processing pattern data to perform the processing of the third step of irradiating the first laser L1 and the second laser L2 across the A pin and the B pin (step S48). In the third step, the A pin and the B pin are rotated and irradiated in an elliptical, circular, 8-shaped, etc.

[0211] The laser processing device 1 heats the A pin and the B pin again in the third step to make the molten portion uniform and form a beautiful symmetrical molten bead. The processing in the third step can be continued until the molten bead reaches the desired size.

[0212] Thus, by performing the third step after the two molten beads 55a and 55b are combined, damage to the lower part of the rectangular line due to the laser passing through the gap is suppressed. Fig.34As shown in (c), pin A and pin B are connected by a molten bead 55, but if the energy of the irradiated laser is strong, the laser will penetrate the molten bead 55, which may cause damage to the lower part of the flat angle line. Therefore, in step 3, the energy density of the laser irradiated on the molten bead 55 is reduced by shifting the focal position of the laser upward. Thus, the penetration of the laser into the molten bead 55 is suppressed. The offset value uses the value recorded in the coordinate table 113. As an example, in the laser processing device 1, the position of the hybrid galvanometer scanner 10 is offset to the height of the higher pin before welding using the z-axis worktable 11z.

[0213] When the welding process of all the rectangular wire pairs included in the workpiece W is completed, the laser processing apparatus 1 completes the welding of the workpiece W.

[0214] As a variation of step 3, use Fig.33 Provide explanation. Fig.33 (a) shows the scanning trajectory of the third step when there is a gap in the x-axis direction. Fig.33 (b) shows the scanning trajectory of the third step when there is a positional deviation in the y-axis direction.

[0215] In either case, the center point of the registered processing graphic data 1100 (8-shaped) is aligned with the AB pin coordinates, and the processing graphic data 1100 is rotated and / or stretched to pass through the A pin coordinates and the B pin coordinates. In this way, the laser can be irradiated with a scanning trajectory corresponding to the various configuration conditions of the A pins and the B pins.

[0216] In addition, the laser scanning trajectory of the third step is an 8-shaped shape, but this is only an example and is not limited to the 8-shaped shape. In the third step, at least in the state where the molten parts of the A pin and the B pin formed in the first step and the second step are combined, the scanning trajectory near the center of the combined molten parts can be used to achieve a process of stirring the molten parts to make them uniform.

[0217] For example, Fig.33 As shown in (c), (d), and (e), the scanning trajectory of the third step can also be a straight line reciprocating irradiation across the A pin and the B pin. In this case, the processing graphic data representing the straight line is registered in advance in the storage unit 202 of the control PC 12, and the control unit 201 corrects the registered processing graphic data according to the configuration status of each pair. Specifically, the center point of the straight line is aligned with the AB pin coordinates, and the straight line is rotated in the θ direction or extended in the x-axis direction so that the starting point and end point of the straight line are aligned with the A pin coordinate and the B pin coordinate. In this way, the straight line reciprocating irradiation corresponding to the configuration status of each pair can be achieved.

[0218] If there is a gap or positional offset between the paired rectangular wires 52 in the x-axis direction, the y-axis direction, and the θ rotation direction, the area of ​​the molten portion joined by irradiation in the first step and the second step can be set to be smaller. Even in the case where the area of ​​the molten portion is small, the laser can be prevented from penetrating through the gap by irradiating the laser with a scanning trajectory passing through the vicinity of the center of the molten portion. Thus, carbonization and poor insulation caused by irradiating the coating portion at the lower part of the rectangular conductor can be prevented.

[0219] (10) Effects of Implementation

[0220] The laser processing device 1 forms a molten pool on the workpiece W by irradiating the first laser L1 with a wavelength of 300nm to 600nm and a high optical absorption rate for copper through high-speed scanning. In addition, by irradiating the inside of the formed molten pool with the second laser L2 with a small focusing diameter and high energy density, a locally deeper melting depth is achieved inside the molten pool, thereby promoting the formation of the molten pool.

[0221] Furthermore, the laser processing device 1 can efficiently apply heat to the workpiece W and melt it by using the first laser light L1 having a larger focusing diameter for welding, compared with a conventional welding device.

[0222] In addition, the laser processing device 1 generates flow in the molten pool by irradiating the first laser L1 and the second laser L2 by high-speed scanning rather than by fixed-point irradiation. This discharges bubbles generated from the molten pool that has reached a high temperature to the outside. As a result, porosity can be suppressed. Furthermore, it is possible to prevent heat from being locally concentrated in the molten pool, stabilize the molten pool, and reduce sputtering. Since porosity and sputtering can be the main causes of welding defects such as poor bonding, the laser processing device 1 of this embodiment and the welding method using these devices can suppress the occurrence of welding defects.

[0223] In addition, as described above, the transmission of laser light from the gap 53 generated when the rectangular wires are butted can be suppressed, and carbonization of the coating portion and insulation failure caused by the transmission of laser light can be suppressed.

[0224] In the case of welding the front ends of two rectangular wires with a step difference, the laser processing device 1 first melts the higher rectangular wire in the first step, and then melts the lower rectangular wire in the second step. At this time, the melting amount in the first step is made larger than the melting amount in the second step. In this way, the step difference can be eliminated and the occurrence of sputtering can be suppressed. When the melting amount in the first step is equal to the melting amount in the second step (for example, if the two molten beads are melted to the extent that they are combined in the shortest time), a Fig.34(d) shows a molten bead 55c inclined as shown. In this case, the welding quality and welding strength are insufficient. In contrast, the laser processing device 1 of this embodiment can form a molten bead 55c as shown in (d) by making the melting amount of the first step greater than the melting amount of the second step. Fig.34 The molten beads 55 shown in (c) are evenly spaced on both sides, and both the welding quality and welding strength are good.

[0225] In addition, the laser processing device 1 includes an image processing unit 9, which obtains the position information (coordinate value) of each pin included in the stator 50, and adjusts the laser irradiation position using the obtained position information. In particular, the laser processing device 1 irradiates the laser with a scanning trajectory passing through the AB pin center coordinates in the processing of the third step, thereby suppressing the laser from passing through the lower part of the rectangular line from the gap or the position shifted portion. As a result, it is possible to suppress the carbonization of the coating and ensure good welding quality and welding strength.

[0226] <Implementation Method 2>

[0227] Next, a laser processing apparatus according to the second embodiment will be described.

[0228] In the first embodiment, the height of each rectangular conductor constituting the segment coil is substantially uniform throughout the motor as the workpiece W to be welded. However, depending on the type of motor, a relatively high rectangular conductor for connecting to a lead wire may exist near the rectangular conductor constituting the segment coil.

[0229] If a taller rectangular conductor stands near the rectangular conductor to be welded, when a molten bead is formed on the end surface of the rectangular conductor to be welded, the laser beam is reflected by the molten bead, and the reflected light may irradiate the coating of the taller rectangular conductor. As a result, the coating may be damaged by heat and become unusable.

[0230] Therefore, the laser processing device of embodiment 2 can prevent the covering portion of the higher rectangular conductor from being damaged by heat and becoming unusable even if a higher rectangular conductor stands near the rectangular conductor to be welded. To this end, a stator manufacturing method is provided, in which welding processing is performed with an appropriate welding pattern according to the peripheral conditions of the rectangular conductor to be welded.

[0231] (1) Structure of laser processing device

[0232] The laser processing device of the second embodiment is the same as the first embodiment, and is a welding device that irradiates the workpiece W with laser light and converts the energy of the laser light into heat to weld the workpiece. Figure 1 and Figure 2 The laser processing devices 1 shown are identical.

[0233] Here, the description will be mainly focused on the control PC 22 which is different from the first embodiment.

[0234] like Fig.38 As shown, the control PC 22 includes a control unit 201 , a storage unit 202 , an input unit 203 , a communication unit 204 , and a display unit 205 .

[0235] The storage unit 202 stores computer programs and various data for controlling the laser processing device. In particular, the storage unit 202 holds the drawing pattern 121 and the pattern table 122 that are the characteristics of this embodiment, which are data for welding the workpiece W. The details will be described later.

[0236] The processing unit 211 of the control unit 201 controls the first oscillator 2, the second oscillator 3, the hybrid galvanometer scanner 10, the PLC 13, the laser controller 14, etc. to perform welding processing on the workpiece W by loading and executing the computer program stored in the storage unit 202 into the RAM serving as a working memory.

[0237] (2) Regarding the workpiece W

[0238] Next, use Fig.39 The stator 50 as the workpiece W will be described. Fig.39 (a) is a perspective view showing a schematic structure of a stator 50 as a stator of a motor of an electric vehicle, etc. As shown in the figure, the stator 50 is composed of a stator core 51 having a substantially cylindrical shape and a plurality of slots 54 arranged in the circumferential direction, a plurality of rectangular wire conductors 2 inserted into the slots 54 to form segment coils, and a plurality of rectangular conductors 60 inserted into the slots 54 and used for conducting electricity to the outside.

[0239] The rectangular conductor 52 and the rectangular conductor 60 are rectangular wires having a rectangular cross section. Generally, the rectangular conductor 52 and the rectangular conductor 60 are made of pure copper wire, but they may also be made of a metal material having high conductivity, such as an alloy mainly composed of copper or an alloy composed of copper and aluminum. The ends of the rectangular conductor 52 and the rectangular conductor 60 protrude from the upper end of the stator core 51, but the protrusion of the rectangular conductor 60 is greater than that of the rectangular conductor 52, that is, the rectangular conductor 60 is higher than the rectangular conductor 52. The rectangular conductor 52 and the rectangular conductor 60 are covered with an insulating film, but the insulating film is peeled off at each end for electrical connection.

[0240] Fig.39 (b) is an enlarged view for explaining an example of the arrangement of the rectangular conductors 52 and the rectangular conductors 60. In this example, the two rectangular conductors 52 to be welded are sandwiched between the two rectangular conductors 60. The laser processing device irradiates the end faces 52a of the two rectangular conductors 52 with laser light to perform welding. Fig.39As shown in (b), if the taller rectangular conductor 60 is close to the rectangular conductor 52 of the welding object, the following problem may occur due to reflected light.

[0241] That is, Fig.40 As shown in FIG. 1 , when two rectangular conductors 52 are welded while being scanned with laser light L1 and L2 by the hybrid galvanometer scanner 10, a hemispherical molten bead 55 is formed on the weld surface (the region where the two end surfaces 52a are joined). From the formation of the molten bead 55 until the welding process is completed, the laser light L1 and L2 are reflected by the molten bead 55. If the reflected light L3 from the molten bead 55 is irradiated on the adjacent rectangular conductor 60, there is a possibility that the coating portion is carbonized and the rectangular conductor 60 becomes unusable.

[0242] In view of such problems, the laser processing apparatus designs the scanning trajectory of the laser, that is, the drawing pattern of the galvanometer scanner 10 , and performs welding processing while suppressing the reflected light L3 of the molten bead 55 from being irradiated onto the adjacent rectangular conductors 60 .

[0243] In addition, among the lasers L1 and L2 irradiated to the molten bead 55, it is mainly the second laser L2 (IR laser) that causes damage to the coating part through reflected light. The absorption rate of IR laser to copper is as low as about 6%, and the remaining about 94% is not absorbed but reflected. In addition, the second laser L2 reflected by the molten bead 55 is diffused, but the fiber laser has the characteristics of high beam quality and difficulty in diffusion, and it is easy to cause damage to the coating part due to reflection. On the other hand, since the absorption rate of the first laser L1 (blue laser) to copper is high, the reflectivity is low. In addition, since the output of the first laser L1 used in this embodiment is low and the diffusion is wide after reflection, the power density of the reflected light is extremely low, so the damage caused by the reflection of the first laser L1 is small.

[0244] (3) Setting and drawing patterns of the irradiation prohibited area

[0245] Here, the drawing pattern used in the welding process of this embodiment is described. Fig.41 Explain the prohibited exposure areas.

[0246] The area affected by the molten bead 55 depends on the distance between the rectangular conductor 52 to be welded and the adjacent rectangular conductor 60, the size of the rectangular conductor 60, the size of the molten bead, the curved surface shape of the molten bead, etc. However, the molten bead 55 grows with the passage of irradiation time, and its size is not constant. In addition, the molten bead 55 is kept in a raised state on the welding surface by surface tension, and is stirred and swung by laser irradiation. Therefore, the shape during the processing is not constant.

[0247] Therefore, in this embodiment, if Fig.41As shown in the figure, the area shown by the oblique line in the figure is defined as the irradiation prohibited area according to the distance between the rectangular conductor 52 to be welded and the adjacent rectangular conductor 60, the size of the rectangular conductor 60, and the size of the welding surface (the area where the two end surfaces 52a are combined). The irradiation prohibited area is an area where the reflected light L3 irradiates the adjacent rectangular conductor 60 when the laser passes through. Therefore, if the laser is irradiated in a drawing pattern so that the laser does not pass through the irradiation prohibited area on the welding surface, the reflected light L3 will not irradiate the rectangular conductor 60.

[0248] Alternatively, the irradiation prohibited area may be determined using at least one of the distance between the rectangular conductor 52 and the adjacent rectangular conductor 60 , the size of the rectangular conductor 60 , the size of the molten bead 55 , the curved surface shape of the molten bead 55 , and the area of ​​the end surface 52 a .

[0249] The laser processing device of this embodiment performs welding processing while switching the drawing pattern according to the surrounding conditions of the rectangular conductor 52 to be welded. That is, when the rectangular conductor 60 is adjacent to the rectangular conductor 52 to be welded, the welding processing is performed with the drawing pattern that does not pass through the irradiation prohibited area, and when the rectangular conductor 60 is not adjacent, the welding processing is performed with the drawing pattern with the highest time efficiency, thereby shortening the takt time of the stator 50 as a whole.

[0250] The drawing pattern 121 stored in the storage unit 202 is composed of a plurality of drawing patterns, such as Fig.42 As shown, it includes pattern A, pattern B, and pattern C. When the UI screen for inputting a drawing pattern is displayed on the display unit 205 , the user can input the drawing pattern 121 by operating the input unit 203 , or read information stored in a portable medium and store it in the storage unit 202 .

[0251] Fig.42 The pattern A shown in (a) is a drawing pattern used when the rectangular conductor 60 is not adjacent to the two rectangular conductors 52 to be welded. In the pattern A, as shown by the trajectory l1, the first laser L1 and the second laser L2 are rotated and irradiated at a predetermined rotation diameter across the two rectangular conductors 52. The melting efficiency of the rotation irradiation of the pattern A is high, and the welding process can be performed faster than the pattern B and the pattern C described later.

[0252] Fig.42 Pattern B shown in (b) is a drawing pattern used when the rectangular conductor 60 is adjacent to the rectangular conductor 52 to be welded. In pattern B, as shown by trajectory 12, the first laser L1 and the second laser L2 are irradiated in an 8-shaped trajectory that does not pass through the irradiation prohibited area.

[0253] Fig.42Pattern C shown in (c) is a modified example of pattern B. Like pattern B, it is a drawing pattern used when the rectangular conductor 60 is adjacent to the rectangular conductor 52 to be welded. As shown in trajectory 13, pattern C reciprocates the irradiation of the first laser L1 and the second laser L2 in an inclined direction that does not pass through the irradiation prohibited area.

[0254] Pattern C is a track connecting two points, so it is a track that is easy to correspond to the surrounding conditions of the molten portion. In addition, since it is a straight line pattern, it has the advantage of low difficulty in generating a depicted pattern. On the other hand, since melting takes time, it is expected that the cycle time will be extended. In addition, there is a possibility that the left and right balance of the molten bead 55 formed on the weld surface will deteriorate.

[0255] The laser processing device performs welding processing on the workpiece W while switching between pattern A and pattern B (pattern C may be used instead of pattern B). At this time, the pattern table 122 stored in the storage unit 202 is used. Fig.43 and Fig.44 The pattern table 122 will be described.

[0256] Fig.43 The stator is simplified and shown as an example of the workpiece W. The two white rectangles forming a pair represent the rectangular conductors 52 to be welded, and the black rectangle represents the rectangular conductors 60 which are relatively high pins. Fig.44 The pattern table 122 shown is a table that describes what drawing patterns are used to perform welding processing on the rectangular conductor 52 to be welded.

[0257] The pattern table 122 corresponds to the workpiece W on a one-to-one basis, and records the drawing patterns corresponding to the arrangement of the rectangular conductors of the workpiece W. The pattern table 122 is stored in the storage unit 102 before the welding process. Similar to the drawing pattern 121, when the UI screen for inputting the pattern table 122 is displayed on the display unit 205, the user can input by operating the input unit 203, or read the information stored in the recording medium and store it in the storage unit 202, or receive it via the network and store it in the storage unit 202.

[0258] The pin number is used as position information indicating the position of the rectangular conductor 52 to be welded. Fig.43 As shown in the figure, the pin number is a combination of letters arranged along the circumferential direction of the stator and numbers arranged along the radial direction of the stator. Fig.44 As shown, the pattern table 122 records the pin numbers and the drawing patterns in correspondence with each other.

[0259] In the present embodiment, when the rectangular conductor 52 to be welded is adjacent to one or more high rectangular conductors 60, pattern B is used, and in other cases, pattern A is used. Specifically, a pair of rectangular conductors 52 identified by pin number "A-1" are adjacent to two rectangular conductors 60, and welding is performed using pattern B. A pair of rectangular conductors 52 identified by pin number "A-2" are adjacent to one rectangular conductor 60, and welding is performed using pattern B. A pair of rectangular conductors 52 identified by pin number "A-3" are not adjacent to the rectangular conductor 60, and welding is performed using pattern A.

[0260] (3) Operation of Laser Processing Device 1

[0261] Here, use Fig.45 The operation of the laser processing apparatus of this embodiment will be described with reference to the flowchart of FIG.

[0262] A pattern table corresponding to the workpiece W set on the workpiece setting table 22 is inputted via the input unit 203 of the control PC 22 (step S51). Next, a drawing pattern (pattern A, pattern B, etc.) required for welding processing of the workpiece W is inputted via the input unit 203 of the control PC 22 (step S52). The order of steps S51 and S52 may be reversed.

[0263] Next, various parameters of the first oscillator 2 and the second oscillator 3 are sent from the control PC 22 to the laser controller 14, and the laser controller 14 sets the parameters for each oscillator (step S53). In addition, the drawing pattern (pattern A, pattern B, etc.) used in the welding process is transmitted from the control PC 22 to the hybrid galvanometer scanner 10.

[0264] Next, the workpiece W is moved by operating the workpiece setting table 11 so that the hybrid galvanometer scanner 10 and the center of the coverage area of ​​the galvanometer scanner 10 on the workpiece W are opposite to each other (step S54). Next, the irradiation position of the galvanometer scanner 10 is aligned with the rectangular conductor 52 recorded in the first row of the pattern table. The steps so far are preparations for welding, and the welding process of the workpiece W is started below.

[0265] The processing unit 211 of the control PC 22 refers to the pattern table stored in the storage unit 202 to determine whether the drawing pattern corresponding to the rectangular conductor 52 currently being welded is pattern A or pattern B (step S56). The processing control unit 211 sends a processing operation command including information identifying the determined processing pattern to the galvanometer scanner 10.

[0266] In the case of pattern A, that is, when the tall rectangular conductor 60 is not adjacent to the rectangular conductor 52, the hybrid galvanometer scanner 10 that has received the processing action command selects pattern A (step S57). In the case of pattern B, that is, when the tall rectangular conductor 60 is adjacent to the rectangular conductor 52, the hybrid galvanometer scanner 10 selects pattern B (step S58).

[0267] After that, the PLC 13 sends a laser irradiation command to the first oscillator 2 and the second oscillator 3. The first oscillator 2 and the second oscillator 3 that receive the laser irradiation command irradiate the first laser L1 and the second laser L2, respectively (step S59). The laser irradiation of step S59 is a three-step laser irradiation consisting of the first step, the second step, and the third step as described in the first embodiment. That is, the laser irradiation of step S59 can also be controlled according to the configuration conditions (gap, positional offset, step difference, etc.) of the pair of rectangular conductors 52 to be welded.

[0268] The galvanometer scanner 10 aligns the irradiation position with the rectangular conductor 52 which is the next welding target (step S60).

[0269] In this embodiment, the operating range of the hybrid galvanometer scanner 10 is set to approximately one-fourth the size of the workpiece W. Therefore, the laser processing apparatus performs welding processing on the entire workpiece W while rotating the workpiece W in 1 / 4 increments on the θ-axis stage 11θ.

[0270] After step S60, the processing unit 211 determines whether the processing of one quarter of the workpiece W is completed (step S61). If the processing of one quarter is not completed ("No" in step S61), the process returns to step S55 and continues the process.

[0271] If one-quarter of the workpiece W is processed ("Yes" in step S61), the processing unit 211 determines whether the entire processing is completed (step S62). If the entire processing of the workpiece W is not completed ("No" in step S62), the processing unit 211 instructs the workpiece W to rotate one-quarter relative to the θ-axis table 11θ via the PLC 13. The θ-axis table 11θ drives the rotation mechanism to rotate the table one-quarter (step S63). After that, the process returns to step S55 and continues processing.

[0272] If the entire processing of the workpiece W is completed (YES in step S62 ), the laser processing apparatus ends the welding processing of the workpiece W.

[0273] (4) Effects of Implementation Method 2

[0274] As described above, the laser processing device of this embodiment switches the drawing pattern according to the situation near the rectangular conductor 52 to be welded while performing welding processing on the entire stator 50. Specifically, when there is a rectangular conductor 60 as a high pin nearby, the laser is irradiated with a drawing pattern that is not affected by the reflected light from the molten bead, and when there is no rectangular conductor 60 nearby, the laser is irradiated with a drawing pattern with the highest melting efficiency. In this way, the tact time can be shortened while avoiding damage caused by reflected light.

[0275] When the workpiece W is changed to a stator having a pin arrangement different from that of the stator 50, the pattern table and the drawing pattern corresponding to the changed stator can be input to the control PC 11. Thus, regardless of the pin arrangement of the stator, damage caused by reflected light can be avoided while shortening the tact time.

[0276] (5) Modification

[0277] In the above-described second embodiment, an embodiment has been described in which a drawing pattern and a pattern table corresponding to the pin arrangement of the workpiece W are stored in advance in the storage unit 202 by the input unit 203 of the control PC 22 .

[0278] Here, a modified example in which the image processing unit 9 analyzes the pin arrangement of the workpiece W and generates a drawing pattern and a pattern table is described. As described in the first embodiment, the image processing unit 9 has a function of imaging the workpiece W placed on the workpiece setting table 11 and analyzing the pin arrangement of the workpiece W. That is, the image processing unit 9 can distinguish whether a tall rectangular conductor 60 is adjacent to the rectangular conductor 52 to be welded. The image processing unit 9 sends the analysis result to the control PC.

[0279] Fig.46 2 is a functional block diagram showing the functional structure of the control PC 23 of the modified example. Fig.38 ) is that the control unit 201 includes a drawing pattern generating unit 212 and a pattern table generating unit 213 in addition to the processing unit 211.

[0280] The processing unit 211 is a functional block for controlling the welding process of the workpiece W, the drawing pattern generating unit 212 is a functional block for generating a drawing pattern using the analysis result of the image processing unit 9, and the pattern table generating unit 213 is a functional block for generating a pattern table using the analysis result of the image processing unit 9. These functional blocks are specifically implemented by computer programs.

[0281] Here, use Fig.47 and Fig.48 The operation of the laser processing apparatus according to the modified example will be described with reference to the flowchart of FIG.

[0282] The image processing unit 9 captures an image of the workpiece W (step S71). The image processing unit 9 analyzes the pin arrangement of the workpiece W based on the image captured in step S71 (step S72), and sends the analysis result to the control PC 23. The analysis result may also be sent to the control PC 23 in the form of a coordinate table 113.

[0283] The pattern table generation unit 213 of the control PC 23 generates a pattern table that associates the pin numbers indicating the positions of the pair of rectangular conductors 52 to be welded with the drawing patterns, using the analysis results of the workpiece W by the image processing unit 9 (step S73). The pattern table generation unit 213 stores the generated pattern table in the storage unit 202.

[0284] Next, the drawing pattern generating unit 212 generates a drawing pattern using the analysis result of the workpiece W by the image processing unit 9 (step S74). Fig.41 As described in the drawing pattern generator 212, the irradiation prohibited area is defined based on the positional relationship between the rectangular conductor 52 and the high rectangular conductor 60 to be welded, the size of each pin, etc., and a drawing pattern (pattern B or pattern C, etc.) is generated in which the irradiation prohibited area is removed. Furthermore, the drawing pattern generator 212 generates pattern A, which is a drawing pattern used when the rectangular conductor 52 is not adjacent to the high rectangular conductor 60. The drawing pattern generator 212 transmits the generated drawing pattern to the hybrid galvanometer scanner 10. In addition, the order of step S73 and step S74 may be reversed.

[0285] Next, various parameters of the first oscillator 2 and the second oscillator 3 are sent from the control PC 23 to the laser controller 14, and the laser controller 14 sets the parameters for each oscillator (step S75).

[0286] Next, the workpiece W is moved by operating the workpiece setting table 11 so that the rectangular conductor 52 recorded in the first row of the pattern table faces the hybrid galvanometer scanner 10 (step S76). The steps up to this point are preparations for welding. Next, welding of the workpiece W is started.

[0287] The processing unit 211 of the control PC 23 refers to the pattern table stored in the storage unit 202 to determine whether the drawing pattern corresponding to the rectangular conductor 52 currently being welded is pattern A or pattern B (step S77). The processing control unit 211 sends a processing operation command including information identifying the determined processing pattern to the galvanometer scanner 10.

[0288] In the case of pattern A, that is, when the tall rectangular conductor 60 is not adjacent to the rectangular conductor 52, the hybrid galvanometer scanner 10 that has received the processing action command selects pattern A (step S79). In the case of pattern B, that is, when the tall rectangular conductor 60 is adjacent to the rectangular conductor 52, the hybrid galvanometer scanner 10 selects pattern B (step S80).

[0289] Thereafter, a laser irradiation command is transmitted from the PLC 13 to the first oscillator 2 and the second oscillator 3. The first oscillator 2 and the second oscillator 3 receiving the laser irradiation command irradiate the first laser light L1 and the second laser light L2, respectively (step S81).

[0290] The laser irradiation in step S81 uses the welding method consisting of three steps described in Embodiment 1. In addition, as described above, the laser irradiation time and the laser irradiation position can be controlled according to the arrangement of the pair of rectangular conductors 52 to be welded. The galvanometer scanner 10 aligns the irradiation position with the rectangular conductor 52 to be welded next (step S82).

[0291] After step S82, the processing unit 211 determines whether the processing of one quarter of the workpiece W is completed (step S83). If the processing of one quarter is not completed ("No" in step S83), the process returns to step S77 and continues.

[0292] If the processing of one quarter of the workpiece W is completed ("Yes" in step S83), the processing unit 211 determines whether the overall processing is completed (step S84). If the overall processing of the workpiece W is not completed ("No" in step S84), the processing unit 211 instructs the workpiece W to rotate one quarter relative to the workpiece setting table 11 via the PLC 13. The workpiece table 11 receiving the instruction from the PLC 13 drives the rotating mechanism (θ-axis table 11θ) to rotate the worktable by one quarter (step S85). Thereafter, the process returns to step S77 to continue processing.

[0293] If the entire processing of the workpiece W is completed (YES in step S62 ), the laser processing apparatus ends the welding processing of the workpiece W.

[0294] As described above, in the laser processing apparatus of the modification, in addition to the functions described in Embodiment 2, the image processing unit 9 analyzes the conditions near the rectangular conductor 52 to be welded. The control PC 23 generates a drawing pattern or a pattern table based on the analysis results.

[0295] According to the present modification, even if the workpiece W is changed, it is not necessary to input a drawing pattern and a pattern table corresponding to the changed workpiece W.

[0296] The arrangement of the rectangular conductors 52 and 60 is an example, and other arrangements are possible. Fig.41 The irradiation prohibited area shown enables welding processing to be performed so that the reflected light from the molten bead does not irradiate all the adjacent rectangular conductors 60.

[0297] For example, Fig.49 As shown, it is also possible to consider a case where the rectangular conductor 52 to be welded is surrounded by tall rectangular conductors 60. In this case, as shown in the track 14 in the figure, welding can be performed by reciprocating irradiation in an inclined direction so that the reflected light from the molten bead does not irradiate all the four adjacent rectangular conductors 60.

[0298] <Other Modifications>

[0299] (1) In the above-mentioned Embodiments 1 and 2, the laser processing apparatus may also include a shielding gas nozzle for supplying shielding gas to the workpiece W. Furthermore, nitrogen gas as shielding gas may be sprayed onto the welding surface at 5 L / min to 100 L / min from the same time as or before the irradiation of the first laser L1 and the second laser L2 until the irradiation is completed or for a longer period of time. More preferably, the spraying may be performed at 10 L / min to 40 L / min, and the welding process may be performed in a nitrogen atmosphere.

[0300] For example, two protective nozzles may be used to spray nitrogen from the left and right of the workpiece W. The angle of each protective nozzle relative to the workpiece W is 0 to 90 degrees relative to the end face inclination angle. In order not to interfere with the operation of the hybrid galvanometer scanner 10, it is more preferably about 30 degrees. The diameter of the front end opening of the protective nozzle (nozzle front end diameter) is preferably about 1 to 10 mm. In addition, the distance from the front end opening of the protective nozzle to the workpiece W, that is, the working distance, is preferably about 5 to 15 mm.

[0301] In this way, the laser processing device 1 welds the workpiece W in a nitrogen atmosphere by supplying nitrogen gas to the workpiece W through the shielding nozzle. The shielding gas prevents oxidation of the weld surface, thereby suppressing the reduction in weld strength and the generation of porosity caused by oxidation of the weld surface. Furthermore, by appropriately selecting conditions such as the flow rate of the shielding gas, the nozzle tip diameter, and the working distance, the shaking of the molten bead can be suppressed and a beautiful molten bead can be formed.

[0302] Alternatively, an air knife may be provided instead of the shielding gas jet.

[0303] (2) In the above-mentioned Embodiments 1 and 2, the trajectory of the laser irradiation in the first step is not limited to linear reciprocating irradiation. In the first step and the second step, the end face 52a of each rectangular conductor 52 may be subjected to circular rotation irradiation or elliptical rotation irradiation. It is preferred to perform irradiation suitable for the size and shape of the end face of the rectangular conductor 52. For example, when performing elliptical rotation irradiation on the rectangular end face 52a, it is preferred to perform irradiation in a manner such that the length direction of the rectangle is the long diameter of the ellipse. In this way, thermal energy can be effectively applied to the end face 52a to promote melting.

[0304] (3) In the first embodiment, the paired rectangular wires 52 are described as having a gap in the x-axis direction, are positionally offset in the y-axis direction, and rotated in the θ direction. The scanning trajectory of the third step in the case of other positional offsets will be described. Fig.33 (a) shows the scanning trajectory of the third step when there is a gap in the x-axis direction. Fig.33 (b) shows the scanning trajectory of the third step when there is a positional deviation in the y-axis direction.

[0305] In either case, the center point of the registered processing graphic data 1100 (8-shaped) is aligned with the AB pin coordinates, and the processing graphic data 1100 is rotated and / or stretched to pass through the A pin coordinates and the B pin coordinates. In this way, the laser can be irradiated with a scanning trajectory corresponding to the various configuration conditions of the A pins and the B pins.

[0306] (4) In the first embodiment, the laser scanning trajectory of the third step is an 8-shaped shape, but this is only an example and is not limited to the 8-shaped shape. The third step can be performed by stirring the molten parts to make them uniform by scanning the molten parts near the center of the molten parts formed in the first and second steps at least in the state where the molten parts of the A pin and the B pin are combined.

[0307] For example, Fig.33 As shown in (c), (d), and (e), the scanning trajectory of the third step can also be a straight line reciprocating irradiation across the A pin and the B pin. In this case, the processing graphic data representing the straight line is registered in advance in the storage unit 202 of the control PC1, and the control unit 201 corrects the registered processing graphic data according to the configuration status of each pair. Specifically, the center point of the straight line is aligned with the AB pin coordinates, and the straight line is rotated in the θ direction or stretched in the x-axis direction so that the starting point and end point of the straight line are aligned with the A pin coordinates and the B pin coordinates. In this way, the straight line reciprocating irradiation corresponding to the configuration status of each pair can be achieved.

[0308] If there is a gap or positional offset between the paired rectangular wires 52 in the x-axis direction, the y-axis direction, and the θ rotation direction, the area of ​​the molten portion joined by irradiation in the first step and the second step can be set to be smaller. Even in the case where the area of ​​the molten portion is small, the laser can be prevented from penetrating through the gap by irradiating the laser with a scanning trajectory passing through the vicinity of the center of the molten portion. Thus, carbonization and poor insulation caused by irradiating the coating portion at the lower part of the rectangular conductor can be prevented.

[0309] (5) As described in the first embodiment, when a rapid temperature rise occurs on the workpiece W, sputtering may occur. Therefore, instead of irradiating the first laser L1 and the second laser L2 at the same time, the workpiece W may be first irradiated with only the first laser L1 having a high absorptivity, and then the second laser L2 may be additionally irradiated after a predetermined time. Thus, a rapid temperature rise of the workpiece W can be suppressed, and the occurrence of sputtering can be suppressed. Furthermore, the workpiece W whose temperature is increased by the first laser L1 increases its absorptivity to the wavelength of the second laser L2, so that the workpiece W can effectively absorb the energy of the second laser L2, thereby shortening the processing time. In this case, it is desirable to irradiate the second laser L2 with a delay of more than 1 millisecond after the irradiation of the first laser L1.

[0310] (6) In Embodiments 1 and 2, the focusing diameter d1 of the first laser L1 is not limited to 1050 μm. The focusing diameter d1 may be selected so that the area of ​​the irradiation region of the first laser L1 (focusing area, spot area) is 1% to 30% of the total area of ​​the workpiece W.

[0311] The focusing diameter d2 of the second laser light L2 is not limited to 40 μm. The focusing diameter d2 of the second laser light L2 may be approximately 10 to 100 μm, and is preferably one tenth or less of the focusing diameter d1 of the first laser light L1.

[0312] The focusing diameter of each laser depends on the core diameter of the transmission fiber, the focal length of the collimating lens, and the focal length of the focusing lens, and can be calculated as focusing diameter = core diameter of the transmission fiber × (focal length of the focusing lens / focal length of the collimating lens). Therefore, by adjusting these optical systems, the focusing diameter of each laser can be changed.

[0313] (7) In the above-mentioned Embodiments 1 and 2, the power of the laser in Step 1, Step 2, and Step 3 is the same, but this is only an example. For example, in the process of Step 3, the output power of the laser can be set to be weaker than that in Step 1 and Step 2. Since Step 3 is a process for homogenizing the molten metal, the same power as that in Step 1 and Step 2 is not required. Furthermore, if too much energy is applied to the workpiece W in Step 3, the laser may pass through the joint, so the energy applied to the workpiece W can be limited by reducing the output power of the laser or changing the focus.

[0314] (8) In the above-mentioned Embodiments 1 and 2, the scanning speed of the first laser L1 and the second laser L2 is described as 500 mm / s. However, the scanning speed of the first laser L1 and the second laser L2 is not limited to this, and may be in the range of 100 to 1000 mm / s.

[0315] (9) The irradiation time of the first step, the second step, and the third step of the above-mentioned embodiment 1 and embodiment 2 is only an example, and is of course not limited to the irradiation time described above. The irradiation time of the first step is the time until a part of the molten portion formed on the end face 52a enters the gap 53, the irradiation time of the second step is the time until a part of the molten portion formed on the end face 52a enters the gap 53, and the irradiation time of the third step is only the time until the two molten portions combined are homogenized to form a single molten portion. These irradiation times can also be changed according to the size of the rectangular conductor to be welded or the interval of the gap, etc.

[0316] (10) In the above embodiment, since the third step is a process for homogenizing the molten metal, the power equivalent to that of the first and second steps is not required. Furthermore, if too much energy is applied to the workpiece W in the third step, the laser may penetrate through the combined molten portion. Therefore, the laser processing device 1 of the first embodiment can achieve the processing of the third step by the following method.

[0317] The first method is to move the focal positions of the first laser L1 and the second laser L2 above the molten portion. This can reduce the power density of the weld surface as the focal diameter increases (divergence) and reduce the risk of laser penetration.

[0318] Compared with the first and second steps, the second method reduces the output power of the first laser L1 and the second laser L2, thereby reducing the power density at the welding surface and the risk of laser penetration.

[0319] The third method is to increase the irradiation speed of the first laser L1 and the second laser L2. By increasing the irradiation speed, the irradiation amount (heat input) per unit area and per unit time of the laser beam passing through the welding surface can be reduced. This can reduce the risk of laser penetration.

[0320] (11) In the above embodiment, a threshold value of the gap amount or the offset amount may be set. If there is a gap or position offset greater than the threshold value, the laser processing device 1 determines that it is an "error (unweldable)" and interrupts the processing, and transfers to the welding processing of the next pair of rectangular wires 52. In this case, the threshold value as a reference for "error" may be pre-stored in the storage unit 202 of the control PC 12. The controller 103 of the image processing unit 9 or the control unit 201 of the control PC 12 measures the gap amount and the offset amount based on the position information (coordinate value) of each rectangular wire 52. The control unit 201 may compare the measured gap amount and the offset amount with the threshold value stored in the storage unit 202.

[0321] (12) In the above embodiment, the first laser light L1 is multi-mode and the second laser light L2 is single-mode. However, this is only an example and does not limit the beam modes of the laser lights.

[0322] (13) In the above-mentioned embodiment, the laser irradiation time for the higher rectangular lines 52 is longer than the laser irradiation time for the lower rectangular lines 52, and the difference becomes larger as the step difference Δz increases. In this way, the laser processing device 1 applies different energies to the rectangular lines 52 due to the difference in laser irradiation time, but this embodiment is only an example. It is sufficient for the laser processing device of the present invention to apply at least more irradiation energy to the higher rectangular lines 52 than to the lower rectangular lines 52.

[0323] In addition, if we observe Fig.29 In field 1111 of the processing rate table 1100 shown, the laser irradiation time of 58 milliseconds for the lower side flat angle line 52 is equivalent to the "baseline energy" of the present invention, and the laser irradiation time of 76 milliseconds for the higher side flat angle line 52 is equivalent to the "additional irradiation energy corresponding to the step difference amount added to the base irradiation energy" of the present invention.

[0324] (14) In the above embodiment, the first laser L1 and the second laser L2 are focused on the workpiece W (welding surface), but in the present invention, both the first laser L1 and the second laser L2 can be focused at a position within the range of ±2 mm in the vertical direction from the welding surface.

[0325] (15) In the above embodiment, the first laser L1 and the second laser L2 are circular beams, but the beam shapes of the first laser L1 and the second laser L2 are not limited thereto. For example, an elliptical beam or a rectangular beam may be used. In this case, it is preferred that the longitudinal direction of the rectangular welding surface is set to the major diameter.

[0326] (16) In the above-mentioned Embodiments 1 and 2, the stator coil is described as an example of a workpiece. However, the above-mentioned welding method and laser device 1 are of course not limited to the case of being used for welding of stator coils.

[0327] (17) In the above-mentioned Embodiments 1 and 2, the optical axis of the first laser L1 and the optical axis of the second laser L2 are aligned, and scanning is performed by the hybrid galvanometer scanner 10. However, the present invention is not limited to this, and the optical axis of the first laser L1 and the optical axis of the second laser L2 may not be consistent, and they may be scanned by different laser scanning optical systems (galvanometer scanners). That is, the present invention also includes a structure in which the laser processing device has two galvanometer scanners, one galvanometer scanner scans the first laser L1, and the other galvanometer scanner scans the second laser L2.

[0328] (18) In the above-mentioned laser device 1, the focusing diameter and output power of each of the first laser L1 and the second laser L2, and the irradiation trajectory, irradiation time, irradiation speed, and number of irradiations of the first step, the second step, and the third step may be input in advance through the input unit 203 of the galvanometer PC (control PC 12) as appropriate values ​​corresponding to the size of the workpiece W. In addition, when the workpiece size or the finished shape of the molten bead is input, the control unit 201 that controls the PC 12 may also determine the focusing diameter, output power, irradiation trajectory, irradiation time, irradiation speed, number of irradiations, and the like of the laser according to a predetermined algorithm.

[0329] (19) In the second embodiment, the movable range of the hybrid galvanometer scanner 10 is set to be approximately one-fourth of the size of the workpiece W. Therefore, the laser processing device performs welding processing on the entire workpiece W while rotating the workpiece W on the workpiece setting table 11 in 1 / 4 increments. At this time, the position of the workpiece W is adjusted using the workpiece setting table 11 so that the nozzle of the galvanometer scanner 10 is directed toward the approximate center of the region that divides the workpiece W into four parts.

[0330] By setting the movable range of the galvanometer scanner 10 to cover the entire workpiece W, the galvanometer scanner 10 can be positioned so that the nozzle faces the center of the workpiece W.

[0331] In addition, if the laser cannot be irradiated to the pin (rectangular conductor 52) to be welded due to obstruction by a high pin (rectangular conductor 60), the workbench 11 can be moved to adjust the position of the pin (rectangular conductor 52) to be welded so that it is arranged approximately directly below the nozzle of the galvanometer scanner 10.

[0332] (20) In the above-mentioned Embodiment 2 and the modification of Embodiment 2, the laser processing device holds or creates a plurality of drawing patterns, and selects an appropriate drawing pattern according to the conditions near the rectangular conductor 52. However, the information held or created by the laser processing device of Embodiment 2 and its modification is not limited to the drawing pattern. In addition to the drawing pattern, it may be a welding pattern combined with the irradiation conditions of the laser, etc. Moreover, it may be a structure in which an appropriate welding pattern is selected according to the conditions near the rectangular conductor 52.

[0333] Examples of the irradiation conditions of the laser light included in the welding pattern include the focal diameter of the laser light, the output power, the irradiation time, the irradiation speed, the number of irradiations, and the like.

[0334] (21) In the above-mentioned Embodiment 2, the laser processing device generates a drawing pattern and a pattern table, but the generation of a drawing pattern is not essential. The laser processing device may also generate only a pattern table based on the analysis result of the image processing unit 9. The drawing pattern can be input by the user through the input unit 203 of the control PC 22.

[0335] (22) In the above-mentioned second embodiment and its modified example, the wire close to the rectangular conductor 52 does not need to be a rectangular wire, and of course it can be a wire of other shapes. In addition, the component close to the rectangular conductor 52 does not need to be a wire, and it can be another component. The laser processing device only needs to select a drawing pattern from a plurality of drawing patterns according to at least the peripheral conditions of the pair of rectangular conductors 52 to be welded, and irradiate the laser with the selected drawing pattern to perform welding processing.

[0336] (23) Here, as a modified example, Fig.50 and Fig.51 The welding process will be described in the case where a positional deviation of xyθ occurs on a pair of rectangular wires 52 to be welded (a case where there is no step in the z-axis direction).

[0337] First, the user operates the input unit 203 of the control PC 12 to input the processed pattern data 1100, and the control PC 12 registers the processed pattern data in the storage unit 202 (step S91). The processed pattern data 1100 is used for laser irradiation in the third step.

[0338] Next, the workpiece W is placed on the workpiece setting table 11. The workpiece setting table 11 on which the workpiece W is placed is moved, and the workpiece W is arranged directly below the image processing unit 9. Then, the image of the workpiece W is captured by the camera device 101 of the image processing unit 9 (step S92).

[0339] The controller 103 of the image processing unit 9 analyzes the image of the workpiece W captured in step S92 to measure the coordinate values ​​of all rectangular lines 52 included in the workpiece W (step S93). Then, the controller 103 records the measured coordinate values ​​in the coordinate table 113 (step S94).

[0340] Next, the control PC 12 sets laser parameters for each of the oscillators 2 and 3 via the laser controller 14 (step S95 ). The workpiece placement table 11 moves the workpiece W to be processed just below the hybrid galvanometer scanner 10 .

[0341] In this modification, the scanning movable range of the hybrid galvanometer scanner 10 is set to be approximately one-fourth of the size of the workpiece W. Therefore, the laser processing device 1 performs welding processing on the entire workpiece W while rotating the workpiece W on the workpiece mounting table 11 in 1 / 4 increments. Thereafter, the laser processing device 1 repeats the processing from step S96 to step S105 for each quarter in the circumferential direction of the workpiece W. Furthermore, the laser processing device 1 repeatedly performs the processing from step S97 to step S103 for each pair of rectangular wires 52 to be welded.

[0342] The control section 201 that controls the PC 12 acquires the paired coordinate values ​​(A pin coordinates and B pin coordinates) in the current process from the coordinate table 113 stored in the storage section 104 of the image processing section 9 (step S98 ).

[0343] The laser device 1 performs the processing of the first step of irradiating the flat angle line 52 (A) on one side with the first laser L1 and the second laser L2 (step S99). In the first step, specifically, a laser irradiation instruction is sent from the PLC 13 to the first oscillator 2 and the second oscillator 3 via the laser controller 14. The first oscillator 2 and the second oscillator 3 that receive the laser irradiation instruction irradiate the first laser L1 and the second laser L2, respectively. At the same time, the control unit 201 of the control PC 12 sends a control instruction to the hybrid galvanometer scanner 10 based on the A pin coordinates obtained in step S98. The galvanometer scanner 10 controls the scanning position according to the control instruction.

[0344] The scanning trajectory of the galvanometer scanner 10 in the first step is linear reciprocating irradiation. The first laser L1 and the second laser L2 perform linear reciprocating irradiation on a predetermined position of the end face 52a. Preferably, linear reciprocating irradiation is performed on a position of the end face 52a close to the butt surface 52b (a position close to the gap). In the first step, laser irradiation is continued until the entire end face 52a of the A pin is melted.

[0345] Next, the laser processing device 1 performs the second step of irradiating the other side's flat angle line 52 (B) with the first laser L1 and the second laser L2 (step S100). The laser irradiation in the second step is also the same as that in the first step, and the galvanometer scanner 10 controls the scanning position based on the B pin coordinates acquired in step S98. The scanning trajectory of the galvanometer scanner 10 in the second step is a linear reciprocating irradiation. The first laser L1 and the second laser L2 perform linear reciprocating irradiation on a predetermined position of the end face 52a. The second step is also the same as the first step, and a linear reciprocating irradiation is performed on a position of the end face 52a close to the butt surface 52b (a position close to the gap). In the second step, laser irradiation is continued until the entire end face 52a of the B pin is melted.

[0346] Alternatively, the laser irradiation in the first step and the laser irradiation in the second step may be performed simultaneously.

[0347] When the molten portion of pin A and the molten portion of pin B are combined, the control unit 201 of the control PC 12 corrects the processing graphic data 1100 stored in the storage unit 102 according to the configuration of pin A and pin B (step S101). The control unit 201 sends the corrected processing graphic data to the galvanometer scanner 10. Then, using the corrected processing graphic data, the third step of irradiating the first laser L1 and the second laser L2 across pin A and pin B is performed (step S102). Through the third step, pin A and pin B are heated again to make the molten portion uniform, forming a beautiful symmetrical molten bead. The processing of the third step can be continued until the molten bead reaches the desired size.

[0348] All pairs of rectangular lines included in the quarter of the workpiece W that is currently being processed are subjected to welding. At this time, the scanning trajectory of step 3 is corrected while welding is being performed according to the configuration of each pair. When the welding of all pairs of rectangular lines included in the quarter of the workpiece W is completed, the control PC 12 rotates the workpiece W by one quarter relative to the workpiece setting table 11 via the PLC 13. The workpiece setting table 11, which receives the instruction from the PLC 13, drives the rotating mechanism (θ-axis table 11θ) to rotate the table by one quarter (step S104). Then, the process returns to step S97 to continue processing.

[0349] The laser processing device 9 processes each quarter of the workpiece W, and when the welding process of all pairs of right angle wires included in the workpiece W is completed, the welding process of the workpiece W is terminated.

[0350] (24) Here, as a modified example, Fig.52 and Fig.53 The welding process will be described in the case where a step difference in the z-axis direction occurs on the paired rectangular wires 52 to be welded (a case where there is no positional deviation in the xyθ directions).

[0351] First, the process starts with the workpiece W being placed on the workpiece setting table 11. The workpiece setting table 11 on which the workpiece W is placed is moved so that the workpiece W is placed directly below the image processing unit 9. Then, the image of the workpiece W is captured by the imaging device 101 of the image processing unit 9 (step S111).

[0352] The controller 103 of the image processing unit 9 analyzes the image of the workpiece W captured in step S111 to measure the coordinate values ​​of all rectangular lines 52 included in the workpiece W (step S112). Then, the controller 103 records the measured coordinate values ​​in the coordinate table 113 (step S113).

[0353] Next, the control PC 12 sends processing pattern data to the hybrid galvanometer scanner 10 and sets laser parameters for each oscillator 2, 3 via the laser controller 14 (step S114). The workpiece placement table 11 moves the workpiece W to be processed directly under the galvanometer scanner 10 (step S115).

[0354] In the present embodiment, the scanning movable range of the hybrid galvanometer scanner 10 is set to be approximately one-fourth of the size of the workpiece W. Therefore, the laser processing device 1 performs welding processing on the entire workpiece W while rotating the workpiece W on the workpiece mounting table 11 in 1 / 4 increments. Thereafter, the processing from step S116 to step S126 is repeated for each quarter in the circumferential direction of the workpiece W. Furthermore, the laser processing device 1 repeatedly performs the processing from step S117 to step S125 for each pair of rectangular wires 52 to be welded.

[0355] The control unit 201 that controls the PC 12 acquires the step amount Δz and the gap amount Δxy currently being processed from the image processing unit 9 (step S118 ).

[0356] The control unit 201 refers to the processing rate table 1100 stored in the storage unit 202, and obtains the laser irradiation time corresponding to the step difference amount Δz and the gap amount Δxy obtained in step S118. As described above, the processing rate table 110 records two values ​​in one field, and the control unit 101 obtains the two values ​​recorded in the upper and lower sections. The value recorded in the upper section is the irradiation time of the first step described later, and the value recorded in the lower section is the irradiation time of the second step described later (step S119).

[0357] Next, the control unit 201 controlling the PC 12 determines which flat angle line in the current processing is higher (step S120). This determination process is performed by receiving information such as a number for identifying the higher flat angle line from the controller 103 of the image processing unit 9, but the control unit 201 may also perform the determination process by reading the coordinate values ​​from the coordinate table 113 stored in the image processing unit 9.

[0358] Next, the laser processing device 1 performs the processing of the first step of irradiating the higher pin with the first laser L1 and the second laser L2 (step S121). Specifically, the laser irradiation time acquired in step S119 is sent from the control unit 201 of the control PC 12 to the laser controller 14, and the laser irradiation time is set for the first oscillator 2 and the second oscillator 3. Furthermore, a control instruction is sent from the control unit 201 to the hybrid galvanometer scanner 10, and a laser irradiation instruction is sent from the PLC 13 to the first oscillator 2 and the second oscillator 3 via the laser controller 14. The first oscillator 2 and the second oscillator 3 that receive the laser irradiation instruction irradiate the first laser L1 and the second laser L2, respectively.

[0359] The scanning trajectory of the galvanometer scanner 10 in step 1 is linear reciprocating irradiation. When the laser is irradiated at the processing rate (irradiation time) acquired in step S9, the B pin is melted to a height slightly lower than the A pin, forming a molten bead 55b. Here, the first laser L1 and the second laser L2 are linearly reciprocatingly irradiated to a predetermined position of the end face 52a, but it is preferred to linearly reciprocately irradiate to a position of the end face 52a close to the butt surface 52b (position close to the gap).

[0360] Next, the laser processing device 1 performs the second step of irradiating the lower pin A with laser light (step S122). In the second step, the first laser light L1 and the second laser light L2 are irradiated on the welding surface of the pin A. The scanning trajectory of the hybrid galvanometer scanner 10 at this time is the same as that in the first step, which is a linear reciprocating irradiation. When the laser light is irradiated at the processing rate (irradiation time) obtained in step S119, the entire end face 52a of the pin A is melted, and a molten bead is formed on the pin A.

[0361] In the second step, similarly to the first step, the position near the butting surface 52b on the end surface 52a (position near the gap) may be irradiated in a linear reciprocating manner. By irradiating the interior with laser light in this manner, the time from the fusion portion to the bonding portion can be shortened.

[0362] Next, before the processing of step 3, the focal positions of lasers L1 and L2 are shifted to the height of pin B before melting (step S123). Then, after the two molten beads are combined, the laser processing device 1 performs the processing of step 3 (step S124). In step 3, rotational irradiation is performed in an elliptical or figure-8 shape across pins A and B. At this time, the hybrid galvanometer scanner 10 uses the AB pin center coordinates to adjust the position of the processing graphic data.

[0363] Through step 3, the B pin previously irradiated with laser is heated again to make the two molten beads uniform, forming beautiful symmetrical molten beads. Step 3 can also be circular rotation irradiation instead of elliptical according to the size or shape of the rectangular line 52.

[0364] In this way, by performing the third step of processing after the two molten beads are combined, damage to the lower part of the rectangular wire due to the laser escaping the gap is suppressed.

[0365] When the welding process of all the paired right angle lines included in the quarter of the workpiece W currently being processed is completed, the control PC 12 instructs the workpiece W to rotate by one quarter relative to the workpiece setting table 11 via the PLC 13. The workpiece setting table 11 receiving the instruction from the PLC 13 drives the rotation mechanism (θ-axis table 11θ) to rotate the table by one quarter (step S126). Then, the process returns to step S117 to continue the process.

[0366] The laser processing device 1 processes each quarter of the workpiece W, and when the welding process of all pairs of rectangular lines included in the workpiece W is completed, the welding process of the workpiece W is terminated.

[0367] (25) Fig.35 , Fig.36 and Fig.37 A specific example of the UI screen displayed on the display unit 205 of the control PC 12 as the galvanometer PC is shown. Fig.35 1 is a diagram showing an example of the main screen 160 displaying the coordinate values ​​of each pin and the laser processing conditions. Fig.36 2 is a diagram showing an example of the processing pattern data registration screen 170 . Fig.37 It is a diagram showing an example of a processing position confirmation screen 180 displayed when the registered processing pattern data is modified or arranged.

[0368] (26) Here, a system for measuring a plurality of measuring objects is described with reference to the accompanying drawings. There is no particular limitation on the type of measuring object, and any object can be used. It is assumed here that they have the same shape. In addition, the so-called "measurement" refers to the presence or absence of measuring objects, the number of objects, the area of ​​objects, the length and circumference of objects, the position of objects, defects and shape characteristics of objects, etc. Here, as an example, the case of measuring the number of measuring objects is described.

[0369] Fig.54 The system 1000 includes: a tray 1003 on which a plurality of measurement objects 1002 are placed; an illumination device 1004 for applying illumination light to the plurality of measurement objects 1002; an imaging device 1005 for capturing images of the measurement objects illuminated by the illumination device 1004; a measuring device 1006 for measuring the measurement objects 1002 using image data captured by the imaging device 1005; and a monitor 1009 for outputting measurement results. Alternatively, an image processing device in which the imaging device 1005 and the measuring device 1006 are integrated, or in which the illumination device 1004, the imaging device 1005, and the measuring device 1006 are integrated, may be used.

[0370] like Fig.54 As shown, the measuring device 1006 includes a memory 1007 and a processor 1008. The memory 1007 stores a measuring program, and the processor 1008 executes the measuring program, so that the measuring device 1006 performs a measuring process of the measuring object.

[0371] Here, as a specific example, Fig.54 The following describes a case where a plurality of measurement objects 1002 placed on a tray 1003 are measured. Fig.55 This is a diagram of the tray 1003 as viewed from above (vertically) on the paper.

[0372] Before the measurement process by the measuring device 1006, the imaging device 1005 first captures the measurement object 1002 on the tray 1003 illuminated by the illumination device 1004. The measuring device 1006 acquires the captured image data and performs measurement based on the image data. Fig.56 Assay processing shown.

[0373] First, the measuring device 1006 performs a first blob analysis process on the image data (step S201). Blob analysis is a type of image analysis that binarizes each pixel included in the target image data and uses the binarized image data to perform various analyses and measurements.

[0374] Fig.571 is a diagram showing image data 100a after binarization processing. In addition, the image data after binarization processing is represented by two grayscales of white and black, but here, for the sake of convenience, Fig.57 As a result of the binarization process, Fig.55 The 16 measurement objects 2 in Fig.57 12 spots from B1 to B12 in FIG. This is because the closely connected measurement object 1002 is represented as one spot by the binarization process. In this state, even if various measurements such as the number and area are performed, accurate measurement results cannot be obtained.

[0375] Therefore, the measuring device 1006 calculates the area of ​​each spot contained in the image data 100a (step S203), and compares the calculated area with a preset threshold value. In this way, it is determined whether the measured objects are combined with each other. The threshold value used for comparison can be set according to the area of ​​the measured object 1002. If the area of ​​the spot is below the threshold value ("No" in step S204), the processing of step S205 is skipped and the process proceeds to step S206. If the area of ​​the spot is greater than the threshold value ("Yes" in step S204), a mask area is configured on the target spot and the spot is segmented (step S205). For example, when the segmentation Fig.58 (a) shows spot B1 (center position is P1), if Fig.58 As shown in (b), a mask area of ​​an elongated shape including the center position P1 (x, y) and parallel to the y-axis is arranged on the image data. The mask area refers to an area that is not recognized in image processing, and a line width of about 1 to 2 pixels is sufficient.

[0376] Since the measuring device 1006 is based on the premise of measuring the number of the measurement objects 1002, the mask region is set to include the center position P1 and parallel to the y-axis as an example, but the method of setting the mask region is not limited to this and can be appropriately changed according to the measurement content.

[0377] Next, the measuring device 1006 performs a second spot analysis process (step S207) to obtain Fig.59 The image data 100b shown in FIG. 100b. In the image data 100b, the spot B1 is divided into the spot B13 and the spot B14, the spot B10 is divided into the spot B15 and the spot B16, and the spot B11 is divided into the spot B17 and the spot B18. The measuring device 1006 measures the number of spots in the image data 100b (step S208). In the first spot analysis process, the number of spots measured is 12, but in the second spot analysis process, the number of spots measured is 16. The measuring device 1006 outputs the measured number of spots to the monitor 1009 as the number of the measurement object 1002.

[0378] In this way, the measuring device 1006 of the measuring system 1 can accurately measure the measuring object 1002 by performing spot analysis processing twice.

[0379] (27) The above-mentioned Embodiment 1, Embodiment 2 and each of the above-mentioned modifications may be appropriately combined.

[0380] (28) In addition, in the above-mentioned embodiments, each component may be implemented by executing a software program suitable for each component. Each component may also be implemented by a program execution unit such as a CPU or a processor reading and executing a software program recorded in a recording medium such as a hard disk or a semiconductor memory.

[0381] In addition, each component can also be implemented by hardware. For example, each component can be a circuit (or integrated circuit). These circuits can constitute a circuit as a whole, or they can be different circuits. In addition, these circuits can be general circuits or dedicated circuits.

[0382] In addition, the whole or specific aspects of the present invention may also be implemented by a system, device, method, integrated circuit, computer program, or a computer-readable CD-ROM or other recording medium. In addition, the present invention may also be implemented by any combination of a system, device, method, integrated circuit, computer program, and recording medium. In addition, the present invention may also be implemented as a computer-readable non-transitory recording medium having such a program recorded thereon.

[0383] In addition, various modifications that can be thought of by those skilled in the art in the art in the present embodiment or combinations of components in different embodiments may also be included in the scope of one or more embodiments of the present invention as long as they do not depart from the spirit of the present invention.

[0384] <Notes>

[0385] A part or all of the above-mentioned embodiment and modified examples may be described as the following supplementary notes.

[0386] (Note 1)

[0387] A welding method, characterized in that:

[0388] The invention relates to a welding method in which the end surfaces of the first component and the second component are arranged opposite to a laser device and welded by laser, and the method comprises:

[0389] In a first step, the first component is irradiated with the laser to form a first molten portion;

[0390] In a second step, the second component is irradiated with the laser to form a second molten portion;

[0391] In a third step, when the first molten portion and the second molten portion are combined, the combined first molten portion and the second molten portion are irradiated with the laser to form a single molten portion.

[0392] The laser light is composed of a first laser light and a second laser light having wavelengths different from each other.

[0393] (Note 2)

[0394] The welding method according to Supplement 1 is characterized in that:

[0395] The focusing diameter of the second laser is smaller than the focusing diameter of the first laser.

[0396] In the first step, the first molten portion is formed by reciprocatingly irradiating a predetermined position of the first member in a substantially linear manner.

[0397] In the second step, the second molten portion is formed by reciprocatingly irradiating a predetermined position of the second member in a substantially linear manner.

[0398] In the third step, when the first molten portion and the second molten portion are joined, the laser beam is irradiated across the first member and the second member.

[0399] (Note 3)

[0400] The welding method according to Supplement 2 is characterized in that:

[0401] In the first step and the second step,

[0402] The predetermined position is a position close to a butting surface between the first member and the second member.

[0403] (Note 4)

[0404] The welding method according to Supplement 1 is characterized in that:

[0405] In the third step, the laser beam is scanned in any shape such as an ellipse, a circle, a polygon, a straight line or an 8-shape across the first component and the second component.

[0406] (Note 5)

[0407] The welding method according to Supplement 1 is characterized in that:

[0408] In the third step, the laser beam is irradiated at a fixed point substantially at the center of the first molten portion and the second molten portion that are joined.

[0409] (Note 6)

[0410] The welding method according to Supplement 1 is characterized in that:

[0411] The wavelength of the first laser is 300 to 600 nm.

[0412] (Note 7)

[0413] The welding method according to Supplementary Note 6 is characterized in that:

[0414] The focusing area of ​​the first laser beam is 1% to 30% of the total area of ​​the end face.

[0415] (Note 8)

[0416] The welding method according to Supplementary Note 6 is characterized in that:

[0417] The output power of the first laser and the second laser is 500 W to 3 kW.

[0418] (Note 9)

[0419] The welding method according to Supplementary Note 6 is characterized in that:

[0420] The energy density of the laser light irradiated in the third step is lower than the energy density of the laser light irradiated in the first step and the second step.

[0421] (Note 10)

[0422] The welding method according to Supplement 1 is characterized in that:

[0423] There is a gap between the first component and the second component,

[0424] The irradiation time of the first step is the time until a part of the first molten portion enters the gap.

[0425] The irradiation time of the second step is the time until a part of the second molten portion enters the gap.

[0426] The irradiation time in the third step is a time until the first molten portion and the second molten portion that are joined become uniform.

[0427] (Note 11)

[0428] The welding method according to Supplement 1 is characterized in that:

[0429] The wavelength of the second laser light is 780 nm to 1100 nm.

[0430] (Note 12)

[0431] The welding method according to Supplementary Note 11 is characterized in that:

[0432] The focusing diameter of the second laser beam is one tenth or less of the focusing diameter of the first laser beam.

[0433] (Note 13)

[0434] The welding method according to Supplementary Note 11 is characterized in that:

[0435] The focusing diameter of the second laser beam is 10 μm to 100 μm.

[0436] (Note 14)

[0437] The welding method according to Supplement 1 is characterized in that:

[0438] The first member and the second member are rectangular conductors having a rectangular cross section constituting a stator coil.

[0439] The end portions of two rectangular conductors disposed opposite to the laser device are butted against each other and welded using the laser and the second laser, thereby forming a molten bead on the end surface.

[0440] (Note 15)

[0441] The welding method according to Supplement 1 is characterized in that:

[0442] From the time of or before the irradiation of the first laser and the second laser until the end of the irradiation or longer, nitrogen gas is blown to the end surface at a flow rate of 5L / min to 100L / min and at an inclination angle of 0 to 90° relative to the end surface.

[0443] (Note 16)

[0444] A laser device is a laser device for welding the end surfaces of a first component and a second component that are butted against each other, characterized in that:

[0445] have:

[0446] a first oscillator for oscillating a first laser beam;

[0447] a second oscillator oscillating a second laser beam having a wavelength different from that of the first laser beam;

[0448] One or more galvanometer scanning units for irradiating the first laser beam and the second laser beam by displacing them in arbitrary directions;

[0449] a control unit that controls the first oscillator, the second oscillator, and the galvanometer scanning unit,

[0450] The laser device irradiates the first component with the first laser and the second laser to form a first melting portion, and irradiates the second component with the first laser and the second laser to form a second melting portion. When the first melting portion and the second melting portion are combined, the first melting portion and the second melting portion combined are irradiated with the first laser and the second laser to form a melting portion.

[0451] (Note 17)

[0452] The laser device according to Supplementary Note 16 is characterized in that:

[0453] The laser device reciprocates the first laser and the second laser in a substantially straight line at a specified position of the first component to form the first melting portion, and reciprocates the first laser and the second laser in a substantially straight line at a specified position of the second component to form the second melting portion. When the first melting portion and the second melting portion are combined, the first laser and the second laser are irradiated across the first component and the second component.

[0454] (Note 18)

[0455] The laser device according to Supplementary Note 17 is characterized in that:

[0456] The laser device further includes a combining unit for superimposing the first laser light and the second laser light on the same optical axis.

[0457] The galvanometer scanning unit irradiates the first member and the second member with the first laser beam and the second laser beam whose optical axes coincide with each other.

[0458] (Note 19)

[0459] The laser device according to Supplementary Note 17 is characterized in that:

[0460] The laser device further comprises an input unit for receiving input from a user.

[0461] The input unit receives various parameters for controlling the first oscillator, the second oscillator, and the galvanometer scanning unit, and outputs the received parameters to the control unit.

[0462] The control unit controls the first oscillator, the second oscillator, and the galvanometer scanning unit based on the parameter acquired via the input unit.

[0463] (Note 20)

[0464] The welding method according to Supplement 1 is characterized in that:

[0465] When there is a gap between the first component and the second component, the molten portion formed by the laser melting at the end faces of each of the first component and the second component enters the gap, whereby, in a state where the two molten portions are combined, the laser is irradiated along a prescribed scanning trajectory passing through the vicinity of the center of the combined molten portions.

[0466] (Note 21)

[0467] The welding method according to Supplementary Note 20 is characterized in that

[0468] The welding method

[0469] The method comprises the steps of obtaining position information of the first component and the second component using an image processing unit,

[0470] Based on the acquired position information, scanning of the laser is controlled.

[0471] (Note 22)

[0472] The welding method according to Supplement 1 is characterized in that:

[0473] There is a step difference caused by positional deviation in the height direction on the end surfaces of the first component and the second component.

[0474] In the first step, the higher end surface of the first component and the second component is irradiated with laser light to be melted.

[0475] In the second step, the lower end surface of the first component and the second component is irradiated with laser light to be melted.

[0476] The melting amount in the first step is larger than the melting amount in the second step.

[0477] (Note 23)

[0478] The welding method according to Supplementary Note 22 is characterized in that:

[0479] The welding method further comprises:

[0480] A step of detecting the heights of the first component and the second component using an image processing unit.

[0481] (Note 24)

[0482] The welding method according to Supplementary Note 23 is characterized in that

[0483] The welding method further comprises:

[0484] a step of acquiring the step difference between the first component and the second component using the image processing unit,

[0485] In the first step, the laser beam is irradiated by adding additional irradiation energy corresponding to the step difference amount to the reference irradiation energy.

[0486] In the second step, laser light is irradiated at a reference irradiation energy.

[0487] (Note 25)

[0488] A welding method for butting the front ends of two right angle wires, irradiating the end faces thereof with a laser, and welding the two right angle wires, characterized in that:

[0489] On the two end faces, there is a step difference caused by the positional deviation of the two straight lines in the height direction.

[0490] The welding method comprises:

[0491] The first step is to irradiate the end surface of the higher straight line with laser light to melt it;

[0492] A second step of irradiating the end face of the lower straight line with laser light to melt it;

[0493] The melting amount in the first step is larger than the melting amount in the second step.

[0494] (Note 26)

[0495] The welding method according to Supplementary Note 25 is characterized in that

[0496] The welding method further comprises:

[0497] The method includes the step of detecting the heights of the two rectangular lines using an image processing unit.

[0498] (Note 27)

[0499] The welding method according to Supplementary Note 26 is characterized in that

[0500] The welding method further comprises:

[0501] The step of obtaining the step difference between the two rectangular lines using the image processing unit,

[0502] In the first step, the laser beam is irradiated by adding additional irradiation energy corresponding to the step difference amount to the reference irradiation energy.

[0503] In the second step, laser light is irradiated at a reference irradiation energy.

[0504] (Note 28)

[0505] The welding method according to Supplementary Note 27 is characterized in that

[0506] The reference irradiation energy is determined by at least one of the power of the laser device, the laser wavelength, the size of the rectangular wire, and the material of the rectangular wire.

[0507] (Note 29)

[0508] The welding method according to Supplementary Note 27 is characterized in that

[0509] The reference irradiation energy is energy required to melt the entire end surface of the rectangular wire.

[0510] (Note 30)

[0511] The welding method according to Supplementary Note 27 is characterized in that

[0512] The additional irradiation energy increases as the step difference amount increases.

[0513] (Note 31)

[0514] The welding method according to Supplementary Note 27 is characterized in that

[0515] There is a gap between the two straight lines caused by position deviation.

[0516] The welding method further comprises:

[0517] The step of obtaining a gap amount indicating the size of a gap between the two rectangular lines using the image processing unit,

[0518] In the first step, the laser beam is irradiated by adding additional irradiation energy corresponding to the step amount and the gap amount to the reference irradiation energy.

[0519] In the second step, laser irradiation is performed by adding additional irradiation energy corresponding to the gap amount to the reference irradiation energy.

[0520] (Note 32)

[0521] The welding method according to Supplementary Note 31 is characterized in that

[0522] The additional irradiation energy increases as the gap between the two rectangular lines increases.

[0523] (Note 33)

[0524] The welding method according to Supplement 30 or Supplement 32 is characterized in that:

[0525] The laser device stores a table recording additional energy corresponding to the step amount and the gap amount.

[0526] The welding method determines the additional energy by referring to the table.

[0527] (Note 34)

[0528] The welding method according to Supplementary Note 25 is characterized in that

[0529] The welding method further comprises:

[0530] After the second step, a third step is performed in which the laser beam is irradiated across the two rectangular lines to stir the molten portion.

[0531] (Note 35)

[0532] The welding method according to Supplementary Note 34 is characterized in that:

[0533] In the third step, the energy of the laser beam irradiated to the molten portion is lower than the energy of the laser beam irradiated in the first and second steps so that the laser beam does not penetrate below the molten portion.

[0534] (Note 36)

[0535] The welding method according to Supplementary Note 35 is characterized in that:

[0536] In the third step, the focal position of the laser beam is shifted upward from the molten portion.

[0537] (Note 37)

[0538] The welding method according to Supplementary Note 25 is characterized in that

[0539] In the first step and the second step, the laser beam is reciprocatedly irradiated to a predetermined position of each rectangular line end surface close to the butting surface.

[0540] (Note 38)

[0541] A laser device is a laser device that butts the front ends of two straight-angle wires of different heights and irradiates the end faces with laser to perform front end butt welding, characterized in that:

[0542] have:

[0543] An image processing unit for detecting the heights of the two straight lines;

[0544] a first oscillator for oscillating a first laser beam;

[0545] a second oscillator oscillating a second laser beam having a wavelength different from that of the first laser beam;

[0546] One or more galvanometer scanning units for irradiating the first laser beam and the second laser beam by displacing them in arbitrary directions;

[0547] a control unit that controls the first oscillator, the second oscillator, and the galvanometer scanning unit,

[0548] The end surface of the high flat angle line is irradiated with the first laser and the second laser to melt it, and then the end surface of the low flat angle line is irradiated with the first laser and the second laser to melt it,

[0549] The melting amount of the high flat angle wire is greater than that of the low flat angle wire.

[0550] (Note 39)

[0551] A welding method is a method of welding the two rectangular wires by butting the front ends of the two rectangular wires together, making the end faces thereof face a laser device, and irradiating the end faces with a laser to weld the two rectangular wires, characterized in that:

[0552] When there is a gap between the two rectangular lines, the end faces of each of the two rectangular lines form a molten portion through laser melting and enter the gap, thereby irradiating the laser with a prescribed scanning trajectory passing through the vicinity of the center of the combined molten portion in a state where the two molten portions are combined.

[0553] (Note 40)

[0554] The welding method according to Supplementary Note 39 is characterized in that

[0555] The welding method

[0556] The method comprises the steps of obtaining the position information of the two straight angle lines by using an image processing unit,

[0557] Based on the acquired position information, scanning of the laser is controlled.

[0558] (Note 41)

[0559] The welding method according to Supplementary Note 40 is characterized in that

[0560] The welding method

[0561] Using the acquired position information, measure the middle point of the two straight angle lines,

[0562] The laser is irradiated with the scanning trajectory crossing the two rectangular lines and passing through the middle point.

[0563] (Note 42)

[0564] The welding method according to Supplementary Note 40 is characterized in that

[0565] The welding method

[0566] Using the acquired position information, measure the center point of each end surface of the two straight angle lines,

[0567] The laser beam is irradiated along the scanning trajectory that crosses the two rectangular lines and passes through the center points of the end surfaces of the two rectangular lines.

[0568] (Note 43)

[0569] The welding method according to Supplementary Note 40 is characterized in that

[0570] The welding method

[0571] The laser beam is irradiated along the scanning track that is substantially in the shape of an 8 and spans the two rectangular lines.

[0572] (Note 44)

[0573] The welding method according to any one of Supplementary Notes 41 to 43, characterized in that:

[0574] The laser device holds processing pattern data representing the prescribed scanning trajectory,

[0575] The welding method further comprises:

[0576] The step of correcting the processing pattern data according to the state of the gap using the acquired position information.

[0577] (Note 45)

[0578] The welding method according to Supplementary Note 39 is characterized in that

[0579] In an xy orthogonal coordinate system with an arbitrary point on the stage on which the flat angle line is placed as the origin,

[0580] The gap is generated when the two rectangular lines are relatively offset in the x-axis direction, relatively offset in the y-axis direction, relatively offset in both the x-axis direction and the y-axis direction, or relatively rotated in the xy plane.

[0581] (Note 46)

[0582] The welding method according to Supplement 45 is characterized in that

[0583] The welding method further comprises:

[0584] A step of detecting a relative offset of the two straight angle lines according to the acquired position information;

[0585] The step of comparing the detected offset with a preset threshold;

[0586] If the detected deviation exceeds the threshold, it is determined that welding is impossible.

[0587] (Note 47)

[0588] The welding method according to Supplementary Note 39 is characterized in that

[0589] The focal position of the laser beam is shifted upward from the molten portion.

[0590] (Note 48)

[0591] The welding method according to Supplementary Note 39 is characterized in that

[0592] The laser is used to stir the combined molten portion to form a molten bead of a desired size or shape.

[0593] (Note 49)

[0594] A welding method is a method of welding the two rectangular wires by butting the front ends of the two rectangular wires together, making the end faces thereof face a laser device, and irradiating the end faces with a laser to weld the two rectangular wires, characterized in that:

[0595] When there is a gap between the two rectangular lines, the laser is irradiated along a predetermined scanning trajectory passing through the vicinity of the center of the joined fusion zone in a state where the end surfaces of the two rectangular lines are joined by the fusion zones formed by the laser melting.

[0596] (Note 50)

[0597] A laser device is a laser device that butts the front ends of two right angle wires and irradiates the end faces with laser to perform front end butt welding, and is characterized by:

[0598] have:

[0599] An image processing unit, which detects position information of the two straight angle lines;

[0600] a first oscillator for oscillating a first laser beam;

[0601] a second oscillator oscillating a second laser beam having a wavelength different from that of the first laser beam;

[0602] One or more galvanometer scanning units for irradiating the first laser beam and the second laser beam by displacing them in arbitrary directions;

[0603] a control unit that controls the first oscillator, the second oscillator, and the galvanometer scanning unit,

[0604] When there is a gap between the two rectangular lines, the end faces of each of the two rectangular lines form a molten portion through laser melting and enter the gap, thereby irradiating the laser with a prescribed scanning trajectory passing through the vicinity of the center of the combined molten portion in a state where the two molten portions are combined.

[0605] (Note 51)

[0606] A method for manufacturing a stator, which is a method for manufacturing a stator for a motor, is characterized by:

[0607] The stator includes: a cylindrical stator core having a plurality of slots arranged in a circumferential direction; and a plurality of rectangular conductors inserted into the slots and joined to each other to form segment coils.

[0608] The end faces of the corresponding two rectangular conductors are butted against each other and face the laser device, a welding pattern is selected from a plurality of welding patterns according to the peripheral conditions of the corresponding two rectangular conductors, and the end faces are irradiated with laser using the selected welding pattern to weld the end faces.

[0609] (Note 52)

[0610] The method for manufacturing a stator according to Supplementary Note 51 is characterized in that:

[0611] A welding pattern is selected according to whether or not other components exist near the two rectangular conductors to be welded.

[0612] (Note 53)

[0613] The method for manufacturing a stator according to Supplementary Note 52 is characterized in that:

[0614] The welding pattern is a drawing pattern representing the irradiation trajectory of the laser on the end surface.

[0615] irradiating the laser beam with a first drawing pattern when no other components are present near the two rectangular conductors to be welded;

[0616] When other members exist near the two rectangular conductors to be welded, the laser beam is irradiated with a second drawing pattern different from the first drawing pattern.

[0617] (Note 54)

[0618] The method for manufacturing a stator according to Supplementary Note 53 is characterized in that:

[0619] The processing time when welding is performed by irradiating the laser beam with the first drawing pattern is shorter than the processing time when welding is performed by irradiating the laser beam with the second drawing pattern.

[0620] (Note 55)

[0621] The method for manufacturing a stator according to Supplementary Note 54 is characterized in that:

[0622] The other member protrudes more from the axial end surface of the stator core than the rectangular conductor.

[0623] The first drawing pattern is an irradiation trajectory that accelerates the melting of the rectangular conductor.

[0624] The second drawing pattern is an irradiation track in which the laser light is reflected by a molten bead generated on the end surface of the rectangular conductor, thereby suppressing the reflected light from irradiating the component.

[0625] (Note 56)

[0626] The method for manufacturing a stator according to Supplementary Note 55 is characterized in that:

[0627] The manufacturing method of the stator

[0628] The area on the welding surface where the reflected light is irradiated to the component when the laser passes through is defined as an irradiation prohibited area,

[0629] The second drawing pattern is an irradiation track that passes through a region on the welding surface excluding the irradiation prohibited region.

[0630] (Note 57)

[0631] The method for manufacturing a stator according to Supplementary Note 56 is characterized in that:

[0632] The manufacturing method of the stator

[0633] The irradiation prohibited area is determined using at least one of the distance between the two rectangular conductors to be welded and the component located near the two rectangular conductors, the size of the component, the size of the molten bead, the curved surface shape of the molten bead, and the area of ​​the weld surface.

[0634] (Note 58)

[0635] The method for manufacturing a stator according to Supplementary Note 57 is characterized in that:

[0636] The other components are wires for connecting electricity to the outside.

[0637] (Note 59)

[0638] The method for manufacturing a stator according to Supplementary Note 52 is characterized in that:

[0639] The laser light is a mixed laser light in which a first laser light and a second laser light having different wavelengths are superimposed on the same optical axis.

[0640] (Note 60)

[0641] The method for manufacturing a stator according to Supplementary Note 59 is characterized in that:

[0642] The first laser wavelength is 300-600 nm,

[0643] The second laser wavelength is 780nm to 1100nm.

[0644] (Note 61)

[0645] The method for manufacturing a stator according to Supplementary Note 60 is characterized in that:

[0646] The second drawing pattern irradiates the laser beam in a figure-8 trajectory across the two rectangular conductors to be welded.

[0647] (Note 62)

[0648] The method for manufacturing a stator according to Supplementary Note 60 is characterized in that:

[0649] The second drawing pattern straddles the two rectangular conductors to be welded, and irradiates the laser light in an oblique direction.

[0650] (Note 63)

[0651] The method for manufacturing a stator according to Supplementary Note 61 or 62, characterized in that:

[0652] The first drawing pattern spans over the two rectangular conductors to be welded, and the laser beam is irradiated in a rotational manner with a predetermined rotation diameter.

[0653] (Note 64)

[0654] The method for manufacturing a stator according to Supplementary Note 63 is characterized in that:

[0655] The manufacturing method of the stator

[0656] The first drawing pattern or the second drawing pattern is selected while referring to information indicating the arrangement state of a plurality of rectangular conductors and other members to be welded.

[0657] (Note 65)

[0658] The method for manufacturing a stator according to Supplementary Note 64 is characterized in that:

[0659] The manufacturing method of the stator

[0660] The stator is analyzed by image processing to generate the information indicating the arrangement state of the plurality of rectangular conductors and the other members to be welded.

[0661] (Note 66)

[0662] A laser device, which is a laser device for manufacturing a stator for a motor, characterized in that:

[0663] The stator includes: a cylindrical stator core having a plurality of slots arranged in a circumferential direction; and a plurality of rectangular conductors inserted into the slots and joined to each other to form segment coils.

[0664] The laser device comprises:

[0665] a first oscillator for oscillating a first laser beam;

[0666] a second oscillator oscillating a second laser beam having a wavelength different from that of the first laser beam;

[0667] a combining unit for superimposing the first laser beam and the second laser beam on the same optical axis;

[0668] a galvanometer scanning unit for irradiating the first laser light and the second laser light whose optical axes coincide with each other by displacing them in an arbitrary direction;

[0669] a stage for mounting the stator so that the end faces of the two corresponding rectangular conductors are butted against each other and face the galvanometer scanning part;

[0670] A control unit controls the first oscillator, the second oscillator and the galvanometer scanning unit, selects a welding pattern from a plurality of welding patterns according to the surrounding conditions of the corresponding two rectangular conductors, irradiates the end face with a laser using the selected welding pattern, and welds the end face.

[0671] (Note 67)

[0672] The laser device according to Supplementary Note 66 is characterized in that:

[0673] The laser device also includes:

[0674] An input unit that inputs information indicating arrangement conditions of a plurality of rectangular conductors and other components in the stator;

[0675] a storage unit for storing the input information,

[0676] The control unit refers to the information stored in the storage unit and selects the one welding pattern from the plurality of welding patterns.

[0677] (Note 68)

[0678] The laser device according to Supplementary Note 66 is characterized in that:

[0679] The laser device also includes:

[0680] an image processing unit for analyzing the arrangement of the plurality of rectangular conductors and other components in the stator;

[0681] a storage unit for storing the analysis result of the image processing unit,

[0682] The control unit refers to the analysis result stored in the storage unit and selects the one welding pattern from the plurality of welding patterns.

[0683] (Note 69)

[0684] A laser processing device, comprising:

[0685] A combining unit that overlaps a plurality of laser beams having different wavelengths on the same optical axis;

[0686] a focus shift section that adjusts the focal length of the laser light overlapped by the combining section;

[0687] A galvanometer scanning unit is located downstream of the focus shift unit and shifts the direction of the optical axis of the laser beam toward the object to be processed.

[0688] The adjustment of the focal length by the focus shift unit and the displacement of the direction of the optical axis by the galvanometer scanning unit are synchronized.

[0689] (Note 70)

[0690] The laser processing device according to Supplementary Note 69, wherein no lens for passing the laser light is provided between the galvanometer scanning unit and the object to be processed.

[0691] (Supplementary Note 71)

[0692] The laser processing device according to Supplement 69 or Supplement 70, wherein:

[0693] The focus shift unit includes a lens that adjusts the focal length of the laser light by moving forward and backward along the optical axis of the laser light.

[0694] The combining section is arranged downstream of the lens included in the focus shift section.

[0695] (Supplementary Note 72)

[0696] According to the laser processing device described in Note 69, Note 70, or Note 71, the focus shift unit has a lens for expanding the diameter of the laser overlapped by the combiner and a lens for reducing the diameter of the laser passing through the lens, so that the relative distance between the two lenses along the optical axis of the laser is expanded and reduced synchronously with the displacement of the direction of the optical axis of the galvanometer scanning unit.

[0697] (Supplementary Note 73)

[0698] The laser processing device according to Supplement 69, Supplement 70, Supplement 71 or Supplement 72,

[0699] It is a device that welds objects by irradiating them with laser.

[0700] The laser beam in which the blue laser beam and the infrared laser beam are superimposed is irradiated onto the object to be processed via the combining unit, the focus shift unit, and the galvanometer scanning unit.

[0701] Description of Reference Numerals

[0702] 1 Laser processing equipment

[0703] 2. 1st oscillator (blue semiconductor laser)

[0704] 3. Second oscillator (infrared fiber laser)

[0705] 9 Image Processing Unit

[0706] 10 Hybrid Galvanometer Scanner

[0707] 11 Workbench

[0708] 12 Control PC (galvanometer PC)

[0709] 13 PLC

[0710] 14 Laser Controller

[0711] 50 Stator

[0712] 52 rectangular conductor, rectangular wire (first part, second part)

[0713] 100 Control Panel

[0714] 101 lighting fixtures

[0715] 102 Camera

[0716] 103 Controller

[0717] 201 Control Department

[0718] 202 Storage

[0719] 203 Input

[0720] 204 Ministry of Communications

[0721] 205 Display

Claims

1. A welding method, characterized in that: The invention relates to a welding method in which the end surfaces of the first component and the second component are arranged opposite to a laser device and welded by laser, and the method comprises: In a first step, the first component is irradiated with the laser to form a first molten portion; In a second step, the second component is irradiated with the laser to form a second molten portion; In a third step, when the first molten portion and the second molten portion are combined, the combined first molten portion and the second molten portion are irradiated with the laser to form a single molten portion. The laser light is composed of a first laser light and a second laser light having wavelengths different from each other.

2. The welding method according to claim 1, characterized in that: The focusing diameter of the second laser is smaller than the focusing diameter of the first laser. In the first step, the first molten portion is formed by reciprocatingly irradiating a predetermined position of the first member in a substantially linear manner. In the second step, the second molten portion is formed by reciprocatingly irradiating a predetermined position of the second member in a substantially linear manner. In the third step, when the first molten portion and the second molten portion are joined, the laser beam is irradiated across the first member and the second member.

3. The welding method according to claim 2, characterized in that: In the first step and the second step, The predetermined position is a position close to a butting surface between the first member and the second member.

4. The welding method according to claim 1, characterized in that: In the third step, the laser beam is scanned in any shape such as an ellipse, a circle, a polygon, a straight line or an 8-shape across the first component and the second component.

5. The welding method according to claim 1, characterized in that: In the third step, the laser beam is irradiated at a fixed point substantially at the center of the first molten portion and the second molten portion that are joined.

6. The welding method according to claim 1, characterized in that: The wavelength of the first laser is 300 to 600 nm.

7. The welding method according to claim 6, characterized in that: The focusing area of ​​the first laser beam is 1% to 30% of the total area of ​​the end face.

8. The welding method according to claim 6, characterized in that: The output power of the first laser and the second laser is 500 W to 3 kW.

9. The welding method according to claim 6, characterized in that: The energy density of the laser light irradiated in the third step is lower than the energy density of the laser light irradiated in the first step and the second step.

10. The welding method according to claim 1, characterized in that: There is a gap between the first component and the second component, The irradiation time of the first step is the time until a part of the first molten portion enters the gap. The irradiation time of the second step is the time until a part of the second molten portion enters the gap. The irradiation time in the third step is a time until the first molten portion and the second molten portion that are joined become uniform.

11. The welding method according to claim 1, characterized in that: The wavelength of the second laser light is 780 nm to 1100 nm.

12. The welding method according to claim 11, characterized in that: The focusing diameter of the second laser beam is one tenth or less of the focusing diameter of the first laser beam.

13. The welding method according to claim 11, characterized in that: The focusing diameter of the second laser beam is 10 μm to 100 μm.

14. The welding method according to claim 1, characterized in that: The first member and the second member are rectangular conductors having a rectangular cross section constituting a stator coil. The end portions of two rectangular conductors disposed opposite to the laser device are butted against each other and welded using the laser and the second laser, thereby forming a molten bead on the end surface.

15. The welding method according to claim 1, characterized in that: When there is a gap between the first component and the second component, the molten portion formed by the laser melting at the end faces of each of the first component and the second component enters the gap, whereby, in a state where the two molten portions are combined, the laser is irradiated along a prescribed scanning trajectory passing through the vicinity of the center of the combined molten portions.

16. The welding method according to claim 15, characterized in that: The welding method The method comprises the steps of obtaining position information of the first component and the second component using an image processing unit, Based on the acquired position information, scanning of the laser is controlled.

17. The welding method according to claim 1, characterized in that: There is a step difference caused by positional deviation in the height direction on the end surfaces of the first component and the second component. In the first step, the higher end surface of the first component and the second component is irradiated with laser light to be melted. In the second step, the lower end surface of the first component and the second component is irradiated with laser light to be melted. The melting amount in the first step is larger than the melting amount in the second step.

18. The welding method according to claim 17, characterized in that: The welding method further comprises: A step of detecting the heights of the first component and the second component using an image processing unit.

19. The welding method according to claim 18, characterized in that: The welding method further comprises: a step of acquiring the step difference between the first component and the second component using the image processing unit, In the first step, the laser beam is irradiated by adding additional irradiation energy corresponding to the step difference amount to the reference irradiation energy. In the second step, laser light is irradiated at a reference irradiation energy.

20. A laser processing device, characterized in that: This is a laser device that welds the end surfaces of the first component and the second component that are butted against each other. It has: a first oscillator for oscillating a first laser beam; a second oscillator oscillating a second laser beam having a wavelength different from that of the first laser beam; One or more galvanometer scanning units for irradiating the first laser beam and the second laser beam by displacing them in arbitrary directions; a control unit that controls the first oscillator, the second oscillator, and the galvanometer scanning unit, The laser device irradiates the first component with the first laser and the second laser to form a first melting portion, and irradiates the second component with the first laser and the second laser to form a second melting portion. When the first melting portion and the second melting portion are combined, the first melting portion and the second melting portion combined are irradiated with the first laser and the second laser to form a melting portion.

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