Laser arc hybrid welding device

Abstract

The present invention provides a laser arc hybrid welding device. The laser arc hybrid welding device includes a laser welding torch and a welding torch. The laser welding torch includes a DOE. The DOE is configured to expand the irradiation area of ​​the laser in the width direction of the welding and adjust the shape of the irradiation area compared to a case where the DOE is not provided, so that the distribution of the heat input amount input by the laser in the width direction has a prescribed curve. The prescribed curve is a curve in which the heat input amount of the central part in the width direction is less than the heat input amount of the end part in the width direction.

Description

Technical Field

[0001] The present invention relates to a laser arc hybrid welding device using laser and arc. Background Art

[0002] Japanese Patent Application Laid-Open No. 2005-40806 discloses a laser irradiation arc welding method, which irradiates a laser beam to an arc generating portion while welding a weld joint in which at least one of the welded parts is a galvanized steel plate and has a gap at the joint portion. In this welding method, the irradiation portion of the laser beam is set to be defocused. Thus, by widely removing the galvanized layer to prevent zinc gas from mixing into the molten pool, the generation of pores and pits is suppressed, and the molten metal is fully filled in the entire gap.

[0003] If the heat input to the joint is large, the temperature (melting temperature) of the molten pool generated during welding increases, and the depth (dissolution depth) of the molten pool also becomes deeper. Therefore, the solidification rate of the molten pool becomes slow, and as a result, the amount of intermetallic compounds generated by welding (for example, alloys of aluminum and iron generated when welding an aluminum plate to a steel plate, etc.) increases. Since intermetallic compounds are more brittle than the parent material itself, if the amount of intermetallic compounds generated increases, the joint strength decreases. It should be noted that in the present invention, "heat input" refers to the total heat input (J) at a certain point or in a certain area until the end of welding. That is, in the present invention, "heat input" does not consider the size of the heat input at a certain moment (W), but considers the heat input time.

[0004] Usually, in order to maximize the irradiation energy density in the irradiation area, the laser is adjusted so as to focus in the irradiation area. However, in this case, the above-mentioned problem may occur due to the increase in the heat input to the joint. On the other hand, if the heat input is reduced, the joint area between the weld bead and the base material is reduced, and as a result, the joint strength may be reduced. The reduction in joint strength caused by the reduction in the joint area can be eliminated by increasing the width of the weld bead.

[0005] Since the welding method described in Japanese Patent Application Laid-Open No. 2005-40806 defocuses the focus of the laser, the heat input to the joint can be suppressed. However, since only the focus of the laser is defocused, the planar shape of the laser irradiation area is generally circular, so the distribution of the heat input in the width direction relative to the welding direction is the largest in the central part and decreases toward the end. Therefore, there is a possibility that the heat input is insufficient at a location far from the central part (for example, the end in the width direction), resulting in insufficient joint strength. Summary of the invention

[0006] The present invention is made to solve the above-mentioned problems, and an object of the present invention is to provide a laser arc hybrid welding device that can suppress the amount of heat input to the joint and form a wider welding bead width to ensure the joint strength.

[0007] The laser arc hybrid welding device of the present invention uses a laser and an arc, and is provided with: a laser welding torch configured to irradiate a laser to a joint; and a welding torch configured to generate an arc between the joint. The laser welding torch includes an adjustment mechanism configured to adjust the shape of an irradiation area of ​​the irradiated laser. The adjustment mechanism is configured to expand the irradiation area in the width direction of the weld and adjust the shape of the irradiation area compared to a case where the adjustment mechanism is not provided in the laser welding torch, so that the distribution of the heat input amount input by the laser in the width direction has a prescribed curve. The prescribed curve is a curve in which the heat input amount in the central part in the width direction is less than the heat input amount in the end part in the width direction.

[0008] In the welding device, by providing the above-mentioned adjustment mechanism, the irradiation area of ​​the laser is expanded in the width direction of the welding, and the heat input amount in the central part in the width direction is suppressed. Therefore, the welding device can suppress the heat input amount input to the joint part and form a wider welding bead width. As a result, the joint strength can be ensured.

[0009] The adjustment mechanism may adjust the shape of the irradiation region so that the irradiation region becomes a rectangle having opposite sides parallel to the advancing direction of the laser welding torch.

[0010] According to this welding device, the amount of heat input to the center portion in the width direction can be suppressed with a simple structure, and the amount of heat input to the end portions in the width direction can be increased.

[0011] The adjustment mechanism may further adjust the distribution of the irradiation energy density in the irradiation region so that the irradiation energy density of the laser light in the center portion in the width direction becomes lower than the irradiation energy density in the end portions in the width direction.

[0012] With such a structure, the heat input amount in the center portion in the width direction is less than the heat input amount in the end portions in the width direction. Therefore, the heat input amount in the width direction after arc welding can be balanced, and a welding bead with good quality can be formed.

[0013] The adjustment mechanism may adjust the shape of the irradiation area so that the length of the irradiation area in the center in the width direction along the traveling direction of the laser welding torch is shorter than the length of the irradiation area in the end portions in the width direction along the traveling direction.

[0014] This structure can also make the heat input amount in the center in the width direction less than the heat input amount in the end parts in the width direction. Therefore, the heat input amount in the width direction after arc welding can be balanced, and a good quality weld bead can be formed.

[0015] It is possible that the distribution of the sum of the heat input amount input by the laser and the heat input amount input by the arc in the width direction may have a prescribed heat distribution.

[0016] This makes it possible to form a desired heat distribution in the width direction by combining the heat input amount by the laser and the heat input amount by the arc, and to form a welding bead of good quality.

[0017] The welding device may further include a control device for adjusting the output of the welding torch. Furthermore, at least one of the adjustment of the shape of the irradiation area by the adjustment mechanism and the adjustment of the output of the welding torch by the control device may be performed so that the sum of the heat input amount by the laser and the heat input amount by the arc in the width direction has a predetermined heat distribution.

[0018] In the case where the mechanical properties of the weld are determined by the heat input to the weld and the heat distribution of each welding process, the desired mechanical properties can be obtained in the weld by adjusting the sum of the heat input by the laser and the heat input by the arc according to the above-mentioned welding device. In addition, especially in welding of dissimilar materials, it is necessary to control the amount of molten metal and its distribution on the basis of controlling the amount of intermetallic compound generated and its distribution. According to the above-mentioned welding device, by adjusting the curve of the heat input by the laser using the adjustment mechanism, the melting of the base material can be mainly adjusted, and the weld bead width, the depth of the molten pool (melting depth) and its distribution can be adjusted. In addition, by adjusting the output of the welding torch using the control device, the melting of the welding wire can be mainly adjusted, so that the amount of molten metal can be adjusted.

[0019] The predetermined curve may be a curve in which the amount of heat input to the center portion in the width direction is smaller than the amount of heat input to the ends in the width direction. Furthermore, the predetermined heat distribution may be uniform in the width direction.

[0020] The welding device can form a high-quality welding bead in which generated intermetallic compounds are not concentrated locally.

[0021] The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1This is a diagram showing the overall configuration of a laser arc hybrid welding device according to Embodiment 1 of the present invention.

[0023] Figure 2 This is a diagram schematically showing the structure of a laser welding torch.

[0024] Figure 3 It is a diagram showing an example of the planar shape of the laser irradiation area.

[0025] Figures 4A to 4C It is a graph showing the distribution of heat input amount in the welding width direction.

[0026] Figure 5 This is a diagram showing an example of a cross section of a joint portion in a fillet weld of a lap joint.

[0027] Figure 6 This is a diagram schematically showing the structure of a laser welding torch in the second embodiment.

[0028] Figure 7 It is a diagram showing an example of the planar shape of the laser irradiation area. DETAILED DESCRIPTION

[0029] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the same or corresponding parts in the drawings are marked with the same reference numerals, and their description will not be repeated.

[0030] [Implementation Method 1]

[0031] Figure 1 1 is a diagram showing the overall structure of a laser arc hybrid welding device according to Embodiment 1 of the present invention. Figure 1 The laser arc hybrid welding device 1 includes a welding torch 10 , a welding wire 20 , a welding power supply device 30 , a laser welding torch 40 , and a laser oscillator 60 .

[0032] The laser arc hybrid welding device 1 can be used for joining metals, especially for welding of dissimilar materials. For example, the laser arc hybrid welding device 1 can be used in welding aluminum alloy plates with molten galvanized steel plates such as GI materials and GA materials. For aluminum alloy plates, not only soft aluminum can be used, but also hard aluminum such as the 5000 series (such as 5052), 6000 series (such as 6063), and 7000 series (such as 7075) of the JIS standard can be used. Through the laser arc hybrid welding device 1, one side and the other side of the welded part 70 are joined, for example, by a fillet weld joint, a flared weld joint, etc.

[0033] The welding torch 10 and the welding power supply device 30 are devices for performing arc welding. The welding torch 10 supplies the welding wire 20 and the shielding gas (not shown) to the joint of the workpiece 70. The welding torch 10 receives the supply of welding current from the welding power supply device 30, generates an arc 25 between the front end of the welding wire 20 and the joint of the workpiece 70, and supplies the shielding gas (argon gas, carbon dioxide gas, etc.) to the welding part. Instead of the welding wire 20, an electrode (tungsten, etc.) of a consumable material may be used. That is, arc welding using the welding torch 10 may be either a consumable electrode type (MAG welding, MIG welding, etc.) or a non-consumable electrode type (TIG welding, etc.).

[0034] Welding power supply device 30 generates a welding voltage and a welding current for arc welding, and outputs the generated welding voltage and welding current to welding torch 10. Welding power supply device 30 also controls the feeding speed of welding wire 20 in welding torch 10.

[0035] The laser welding torch 40 and the laser oscillator 60 are devices for performing laser welding. The laser welding torch 40 receives the supply of laser light from the laser oscillator 60 and irradiates the joining portion of the workpiece 70 with the laser light.

[0036] In the laser arc hybrid welding device 1 of the present invention, the laser welding torch 40 includes an adjustment mechanism that adjusts the shape of the irradiation area of ​​the irradiated laser and the distribution of the irradiation energy density of the laser in the irradiation area. The adjustment mechanism expands the irradiation area in the width direction of the weld compared to a case where the adjustment mechanism is not provided. Moreover, the adjustment mechanism adjusts the shape of the irradiation area and the distribution of the irradiation energy density so that the distribution of the heat input (J) input by the laser in the welding width direction becomes a curve in which the heat input in the central part in the width direction is less than the heat input in the end parts in the width direction. In the present embodiment 1, as such an adjustment mechanism, a diffractive optical element (DOE: Diffractive Optical Element) is provided in the laser welding torch 40. The structure of the laser welding torch 40 is described later.

[0037] By providing such an adjustment mechanism in the laser welding torch 40 , the amount of heat input to the joint portion can be suppressed, and a wide welding bead width can be formed, thereby ensuring the joint strength. This point will be described in detail below.

[0038] As described above, if the amount of heat input (J) to the joint increases, the solidification rate of the molten pool will be slower, and the amount of intermetallic compounds generated by welding will increase. For example, when welding an aluminum alloy plate to a galvanized steel plate, an alloy of aluminum and iron (FeAl, Fe 3 Al, Fe 2 Al5 、FeAl 3 The more heat input to the joint, the more it is generated. Such intermetallic compounds are more brittle than the base material, so if the amount of intermetallic compounds generated increases, the joint strength decreases.

[0039] Generally, in order to increase the irradiation energy density in the irradiation area and effectively melt the component, the focus of the laser is adjusted to focus in the irradiation area. However, in this case, the amount of heat input to the joint portion increases, and as described above, the amount of intermetallic compound generated increases, the joint strength may decrease.

[0040] Therefore, in order to suppress the amount of intermetallic compounds generated, it is possible to suppress the amount of heat input, but if the amount of heat input is suppressed, the joining area between the weld bead and the base material is reduced, resulting in a possible reduction in the joining strength. By increasing the width of the weld bead, the reduction in joining strength caused by the reduction in the joining area can be eliminated.

[0041] It is conceivable to defocus the laser focus to suppress the heat input. However, since only the laser focus is defocused, the planar shape of the laser irradiation area is generally circular, so the distribution of heat input in the welding width direction is the largest in the central part and decreases toward the end. Therefore, there is a possibility that the heat input is insufficient at a location far from the central part (for example, the end in the width direction), resulting in insufficient joint strength.

[0042] Therefore, in the laser arc hybrid welding device 1 of the first embodiment, the DOE as the above-mentioned adjustment mechanism is provided in the laser welding torch 40. By providing such an adjustment mechanism (DOE), the heat input to the joint portion can be suppressed and a wider welding bead width can be formed. As a result, the joint strength of the joint portion can be ensured.

[0043] Figure 2 4 is a diagram schematically showing the structure of the laser welding torch 40. Figure 2 The laser welding torch 40 includes a DOE 41 and a lens 42 . The laser light outputted from the laser oscillator 60 is irradiated to the workpiece 70 through the DOE 41 and the lens 42 , and forms an irradiation region 80 in the workpiece 70 .

[0044] DOE 41 processes the laser light received from the laser oscillator 60 into a desired beam pattern by utilizing the diffraction phenomenon. Specifically, DOE 41 geometrically disperses the incident light received from the laser oscillator 60 and shapes the irradiated laser light so that the irradiated area 80 on the workpiece 70 is wider and roughly rectangular than when DOE 41 is not provided.

[0045] The lens 42 focuses the laser light processed by the DOE 41 and outputs the laser light toward the workpiece 70 .

[0046] Figure 3 is a diagram showing an example of the planar shape of the irradiation area 80. Figure 3 In FIG. 4 , the X-axis direction represents the traveling direction of the laser welding torch 40, and the Y-axis direction represents the width direction of the welding. Figure 3 , the laser is processed by DOE41 so that the irradiation area 80 becomes a roughly rectangular shape.

[0047] The dashed line group indicates the distribution of the irradiation energy density of the laser. As shown in the figure, in the irradiation area 80, the laser is shaped by the DOE 41 so that the irradiation energy density increases from the center C in the width direction (Y-axis direction) toward the ends in the width direction.

[0048] It should be noted that, in this example, the opposite sides of the irradiation area 80 parallel to the travel direction (X-axis direction) of the laser welding torch 40 are short sides, and the opposite sides parallel to the width direction (Y-axis direction) are long sides, but the irradiation area 80 can be a roughly square, or the opposite sides parallel to the travel direction (X-axis direction) of the laser welding torch 40 can be long sides.

[0049] Figures 4A to 4C It is a graph showing the distribution of heat input amount in the welding width direction. Figure 4A shows the distribution of heat input by the laser, Figure 4B The distribution of heat input by the arc is shown. Figure 4C The distribution of the sum of the heat input by the laser and the heat input by the arc is shown. That is, Figure 4C The distribution of the total heat input by the laser and the arc is shown. In each figure, the vertical axis represents the heat input Q, and the Y-axis direction represents the width direction of the weld. The heat input Q is the total heat input (J) from the start to the end of the weld at each point in the width direction.

[0050] Reference Figures 4A to 4C , by having Figure 3 The laser irradiation of the irradiation area 80 shown in FIG. 8 is performed, and the distribution of the heat input amount input by the laser is as shown in FIG. Figure 4A The curve shown is that the heat input amount is small in the center C in the width direction, and the heat input amount increases toward the end. It should be noted that, for reference only, when the plane shape of the laser irradiation area is assumed to be circular, even if the irradiation energy density in the center is reduced and the irradiation energy density in the peripheral part is increased in the irradiation area, the heat input amount increases in the center in the width direction and is likely to decrease toward the end in the width direction.

[0051] like Figure 4BAs shown in FIG. 1 , the distribution of heat input by the arc forms a curve in which the heat input is greater in the center C in the width direction and the heat input decreases toward the end. Figure 4C As shown, the heat distribution of the sum of the heat input amount by the laser and the heat input amount by the arc is approximately uniform in the width direction.

[0052] In other words, the curve of the heat input amount by the laser is determined in such a way that the curve of the heat input amount by the laser and the heat input amount by the arc is substantially uniform in the width direction, taking into account the curve of the heat input amount by the arc. Then, the shape of the irradiation area 80 of the laser and the irradiation energy density distribution ( Figure 3 The shape and irradiation energy density distribution shown in the figure) are used to determine the structure of DOE41 that realizes such an irradiation area 80.

[0053] Or, it can be that Figure 4A DOE41 is constructed in the form of a curve of the heat input amount input by laser as shown, and the output of the welding torch 10 is adjusted by the welding power supply device 30 (control device) so that the curve of the heat distribution of the sum of the heat input amount input by laser and the heat input amount input by arc is approximately uniform in the width direction.

[0054] Since the mechanical properties of the weld are determined by the heat input to the weld and the heat distribution of each welding process, the desired mechanical properties can be obtained at the weld by adjusting the sum of the heat input by the laser and the heat input by the arc as described above. In addition, by making the sum of the heat input by the laser and the heat input by the arc uniform in the width direction, a high-quality weld bead can be formed in which the generated intermetallic compounds are not concentrated locally.

[0055] It should be noted that, in particular, in welding of dissimilar materials (for example, welding of an aluminum alloy plate and a molten galvanized steel plate, etc.), it is necessary to control the amount of molten metal and its distribution on the basis of controlling the amount of intermetallic compound generated and its distribution. In this embodiment, by adjusting the curve of the heat input amount input by the laser using the adjustment mechanism as described above, the adjustment can be mainly made based on the melting of the base material, and the weld bead width, the depth of the molten pool (melting depth) and its distribution can be adjusted. In addition, by adjusting the output of the welding torch 10 using the welding power supply device 30, the adjustment can be mainly made based on the melting of the welding wire, and the amount of molten metal can be adjusted.

[0056] Figure 5 1 is a diagram showing an example of a cross section of a joint portion in a fillet weld of a lap joint. Figure 5In this example, the welded part 70 includes a GI material 71 and an aluminum alloy plate 72 stacked on the GI material 71. The welding bead 73 indicated by the solid line is a welding bead when fillet welding is performed using the laser arc hybrid welding device 1 of the present embodiment 1 (hereinafter, sometimes referred to as "welding device 1"). On the other hand, as a comparative example, the welding bead 75 indicated by the dotted line is a welding bead when fillet welding is performed using a laser arc hybrid welding device (hereinafter, referred to as "conventional type welding device") that does not have a DOE 41.

[0057] When welding is performed using an existing type of welding device, since the laser irradiation area is narrow (it should be noted that when the laser irradiation area is narrow, the width of the arc also becomes narrow) and the irradiation energy density in the central part of the irradiation area is high, the penetration depth of the base material is deep, and a welding bead 75 with a narrow contact portion 76 with the base material (GI material 71) is formed.

[0058] In contrast, when welding is performed using the welding device 1, since the laser irradiation area is wider (when the laser irradiation area is wider, the width of the arc also becomes wider), and the heat input in the central part of the irradiation area is suppressed and the heat input in the width direction is balanced, the depth of melting into the base material is suppressed, and the contact portion 74 in contact with the base material forms a wider welding bead 73 relative to the above-mentioned contact portion 76.

[0059] In this way, the solidification speed when the weld bead 73 is generated, which has a shallower dissolution depth to the base material than the weld bead 75 and a larger contact portion with the base material, is faster than the solidification speed when the weld bead 75 is generated. Therefore, the amount of intermetallic compounds generated at the weld bead 75 is smaller than the amount of intermetallic compounds generated at the weld bead 73. In addition, the contact portion 74 where the weld bead 73 contacts the base material (GI material 71) is larger than the contact portion 76 where the weld bead 75 contacts the base material. Based on the above, the bonding strength of the weld bead 75 is higher than the bonding strength of the weld bead 73.

[0060] As described above, according to the first embodiment, by setting Figure 3 The distribution of heat input in the width direction of the DOE41 in the laser irradiation area shown in FIG. Figures 4A to 4C Therefore, the heat input to the joint can be suppressed and a wider welding bead width can be formed. As a result, the joint strength of the joint can be ensured.

[0061] In addition, according to the first embodiment, by adjusting the distribution (curve) of the sum of the heat input amount by the laser and the heat input amount by the arc in the width direction, desired mechanical properties can be obtained at the welded portion. Furthermore, by making the distribution of the sum of the heat input amount by the laser and the heat input amount by the arc in the width direction uniform in the width direction, a high-quality weld bead can be formed in which the generated intermetallic compounds are not concentrated locally.

[0062] In addition, by adjusting the curve of the heat input amount input by the laser using the adjustment mechanism (DOE41) as described above, the melting of the base material can be adjusted, and the weld bead width, the depth of the molten pool (penetration depth) and its distribution can be adjusted. In addition, by adjusting the output of the welding torch 10 using the welding power supply device 30, the melting of the welding wire can be adjusted, and the amount of molten metal can be adjusted.

[0063] [Implementation Method 2]

[0064] In the first embodiment, DOE 41 is used as follows Figure 3 In the second embodiment, a laser scanning device capable of scanning the laser beam irradiated to the welded workpiece 70 is provided on the laser welding torch instead of the DOE, and the same irradiation area as in the first embodiment is formed by scanning the laser beam with the laser scanning device.

[0065] The overall structure of the laser arc hybrid welding device in the second embodiment is Figure 1 The laser arc hybrid welding devices 1 shown are identical.

[0066] Figure 6 FIG. 2 is a diagram schematically showing the structure of a laser welding torch in Embodiment 2. Figure 6 The laser welding torch 40A includes a scanning mirror 44 and an optical axis control device 45, which replaces the Figure 2 A DOE 41 is shown in a laser welding torch 40 .

[0067] The scanning mirror 44 and the optical axis control device 45 correspond to the adjustment mechanism in the present invention, and constitute a laser scanning device capable of scanning the laser on the workpiece 70. The scanning mirror 44 reflects the laser received from the laser oscillator 60 and outputs it to the lens 42. The scanning mirror 44 is configured to be able to change the direction by the optical axis control device 45, so that the irradiation position 81 of the laser irradiated through the lens 42 can be changed. The scanning mirror 44 includes, for example: an X scanning mirror, which can change the irradiation position 81 in the X direction; and a Y scanning mirror, which can change the irradiation position 81 in the Y direction.

[0068] The optical axis control device 45 includes: a driving device that changes the angle of the scanning mirror 44; and a control device that adjusts the irradiation position 81 of the laser by controlling the driving device (neither of which is shown in the figure). The driving device includes, for example: an X-axis motor that drives the X scanning mirror to rotate; and a Y-axis motor that drives the Y scanning mirror to rotate.

[0069] With such a structure, by scanning the laser on the workpiece 70, a layer similar to the layer to be welded can be formed on the workpiece 70. Figure 3 The irradiation area 80 shown in FIG. 8 is a rectangular irradiation area 82 which is equivalent to the irradiation area 80 shown in FIG. 8. It should be noted that by appropriately adjusting the output and / or scanning speed of the laser together with the scanning position of the laser, the irradiation area 82 can be adjusted as shown in FIG. Figure 3 A curve of the irradiation energy density within the irradiation area 82 is adjusted as shown in the dotted line.

[0070] As described above, the same effects as those of Embodiment 1 can be obtained according to Embodiment 2. In addition, according to Embodiment 2, the scanning mirror 44 and the optical axis control device 45 are used to form the irradiation area 82 having the desired shape and irradiation energy density distribution, so the degree of freedom in forming the desired irradiation area 82 is high.

[0071] [Modifications]

[0072] In the first embodiment, DOE 41 is used to form Figure 3 The irradiation area 80 of the laser beam is as shown. That is, the planar shape of the irradiation area 80 is rectangular, and the irradiation energy density is distributed in the irradiation area 80 so that the irradiation energy density increases from the center in the width direction toward the ends in the width direction.

[0073] However, the irradiation area 80 formed by the DOE 41 is not limited to having such a shape and irradiation energy density distribution. Figure 7 As shown, within the irradiation area 80, the length of the irradiation area in the center C in the width direction (Y-axis direction) along the welding progress direction (X-axis direction) is shorter than the length of the irradiation area at the end in the width direction, and the irradiation energy density in the width direction is roughly uniform.

[0074] By using the irradiation area 80 having such a shape and irradiation energy density distribution, it is also possible to obtain Figure 4A Therefore, the same effect as that of the first embodiment can be obtained.

[0075] It should be noted that, for the second embodiment, the laser welding torch 40A can also be used to form a Figure 7 The irradiation area 82 has the shape and irradiation energy density distribution as shown.

[0076] In addition, in each of the above-mentioned embodiments and modified examples, the curve of the heat input amount by the laser is determined in such a manner that the curve of the sum of the heat input amount by the laser and the heat input amount by the arc is substantially uniform in the width direction, or the output of the welding torch 10 is adjusted by the welding power supply device 30, but the curve of the sum of the heat input amount by the laser and the heat input amount by the arc in the width direction is not limited thereto. The curve of the sum of the heat input amount by the laser and the heat input amount by the arc may be a predetermined curve in which the heat input amount in the center portion in the width direction is greater than the heat input amount in the end portions in the width direction to the extent that the heat input amount in the center portion in the width direction does not become excessive, or may be a predetermined curve in which the heat input amount in the center portion is less than the heat input amount in the end portions.

[0077] Furthermore, in each of the above-mentioned embodiments and variations, the curve of the heat input amount input by the laser is as follows: Figure 4A Although the heat input decreases in the center in the width direction as shown in the figure, the heat input by the laser can also be made substantially uniform in the width direction. In this case, regarding the curve of the sum of the heat input by the laser and the heat input by the arc, although the heat input in the center is greater than that in the end, the heat input in the center can be suppressed and the distribution of the heat input in the width direction can be expanded compared to the case where the curve of the heat input by the laser is not adjusted.

[0078] The embodiments disclosed this time should be considered as illustrative in all aspects and not restrictive. The scope of the present invention is indicated by the scope of the claims, and all modifications within the scope and meaning equivalent to the scope of the claims are included.

Claims

1. A laser arc hybrid welding device, which uses laser and arc, wherein: The laser arc hybrid welding device comprises: a laser welding torch configured to irradiate a laser beam toward a joining portion; a welding torch configured to generate an arc between the welding torch and the joint; and a control device that adjusts the output of the welding torch, The laser welding torch includes an adjustment mechanism configured to adjust the shape of an irradiation area of ​​the irradiated laser. The adjustment mechanism is configured to expand the irradiation area in the width direction of welding and adjust the shape of the irradiation area compared to a case where the laser welding torch is not provided with the adjustment mechanism, so that the distribution of the heat input amount input by the laser in the width direction has a predetermined curve, The heat input refers to the total heat input at a certain point or area until the end of welding. It is not the amount of heat input at a certain moment, but also takes into account the heat input time. The predetermined curve is a curve in which the amount of heat input at the center portion in the width direction is smaller than the amount of heat input at the end portions in the width direction. The sum of the heat input amount input by the laser and the heat input amount input by the arc has a prescribed heat distribution in the width direction. The laser arc hybrid welding device performs at least one of the adjustment of the shape of the irradiation area by the adjustment mechanism and the adjustment of the output of the welding torch by the control device, so that the distribution of the sum of the heat input amount input by the laser and the heat input amount input by the arc in the width direction has the specified heat distribution, The prescribed heat distribution is uniform in the width direction, The adjustment mechanism further adjusts the distribution of irradiation energy density in the irradiation region so that the irradiation energy density of the laser light at the center portion in the width direction becomes lower than the irradiation energy density at the end portions in the width direction.

2. The laser arc hybrid welding device according to claim 1, wherein: The adjustment mechanism adjusts the shape of the irradiation region so that the irradiation region becomes a rectangle having opposite sides parallel to the advancing direction of the laser welding torch.

3. The laser arc hybrid welding device according to claim 1, wherein: The adjustment mechanism adjusts the shape of the irradiation area in such a manner that the length of the irradiation area in the center portion in the width direction along the traveling direction of the laser welding torch is shorter than the length of the irradiation area in the end portions in the width direction along the traveling direction.

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