JP6966977B2 - Laser welding method and laser welding equipment - Google Patents

Description

The present invention relates to a laser welding method and a laser welding apparatus.

In the laser welding method disclosed in Patent Document 1, the first metal member is placed on the table, and the second metal member is placed on the first metal member. The first and second metal members are attracted to and held by the table by the magnetic force generated by the magnetic field generator, and are welded by the laser beam emitted from above. According to this welding method, by utilizing the magnetic force, the adhesion between the first metal member and the second metal member is ensured better than the case where the first and second metal members are temporarily fixed by a jig. ..

Japanese Unexamined Patent Publication No. 8-333996

The laser welding method of Patent Document 1 has the following problems.

The top surface of the table is just a flat surface. Therefore, the penetration depth needs to be stopped inside the first metal member, and through welding, that is, welding in a mode in which the penetration depth reaches the lower surface of the first metal member cannot be performed. If through welding is performed, problems such as damage to the upper surface of the table and joining of the first metal member to the table may occur.

Since the keyhole does not penetrate, not through welding, welding defects such as blowholes may occur. Further, since it is not through welding, the amount of penetration cannot be determined from the appearance after welding.

Since the entire lower surface of the first metal member is in close contact with the upper surface of the table, the heat dissipation of welding heat is not good. Therefore, the penetration depth tends to change during welding due to the temperature rise of the first and second metal members due to the welding heat, which is not suitable for long-time welding and continuous welding.

An object of the present invention is to prevent or suppress the occurrence of welding defects such as blow holes while improving the welding quality by ensuring the adhesion between the first metal member and the second metal member during laser welding in laser welding. And.

The first aspect of the present invention is a laser welding method in which a first metal member and a second metal member made of a magnetic material are welded, and a table having a recess recessed from the upper surface and an arrangement below the table. The first metal member is placed on the upper surface of the table, and the second metal member is placed on the first metal member, and the second metal member is placed on the first metal member. Positioned above the recess, the second metal member is attracted to the table together with the first metal member by the magnetic attraction force generated by the magnetic field generated by the magnetic field generator, and the first metal member is attracted by the magnetic attraction force. While maintaining the state in which the first and second metal members are attracted to the table, the second metal member is irradiated with laser light from the laser oscillation system, and the first metal member and the second metal member are joined to each other. Provided is a laser welding method for forming a welded portion.

The irradiation conditions of the laser beam are set so that the penetration depth reaches the lower surface of the first metal member.

The second metal member is attracted to the table together with the first metal member by the magnetic attraction force generated by the magnetic field generated by the magnetic field generator. Therefore, high adhesion between the first metal member and the second metal member is ensured, and the welding quality is improved.

Since the second metal member is located above the recess of the table, the irradiation conditions of the laser beam from the laser oscillation system can be set so that the penetration depth reaches the lower surface of the first metal member. That is, the first metal member and the second metal member can be through-welded. Since the keyhole penetrates through the penetration welding, it is possible to prevent or suppress the occurrence of welding defects such as blowholes. Further, since it is through welding, the amount of penetration can be determined from the appearance after welding.

Since the lower surface of the first metal member in the portion where the second metal member is placed does not adhere to the upper surface of the table but covers the concave portion, the welding heat is effectively dissipated. As a result, it is possible to suppress the change in the penetration depth during welding due to the temperature rise of the first and second metal members, and it is suitable for long-time welding and continuous welding.

The outer contour of the recess in the plan view is smaller than the outer contour of the first metal member in the plan view, and larger than the outer contour of the second metal member in the plan view.

A copper plate may be removably arranged at the bottom of the recess.

Spatter generated during laser welding adheres to the copper plate. The spatter-attached copper plate can be removed from the recess to remove the spatter, or it can be replaced with a new copper plate. This makes it possible to suppress changes in welding characteristics due to adhesion of spatter.

The table may be cooled during irradiation with the laser beam.

The first metal member may be a magnetic material.

When the first metal member directly placed on the upper surface of the table is made of a magnetic material, the lower surface of the first metal member is entirely on the upper surface of the table except for the portion covering the recess due to the magnetic force generated by the magnetic force generator. Be restrained. As a result, the first metal member is held on the upper surface of the table in a state where deformation such as warpage is suppressed and has a high flatness, and the adhesion between the first metal member and the second metal member is further improved.

A second aspect of the present invention is a laser welding apparatus for welding a first metal member and a second metal member made of a magnetic material, the second metal member having a recessed recess from the upper surface. A table on which the first metal member is placed on the upper surface and a table on which the second metal member is placed so as to be located above the recess.
A laser beam is applied to the magnetic field generator and the second metal member, which are arranged below the table and generate a magnetic field that attracts the second metal member to the table by magnetic attraction together with the first metal member. Provided is a laser welding apparatus including a laser oscillation system for irradiating.

According to the laser welding method and the laser welding apparatus according to the present invention, welding defects such as blow holes are generated while improving the welding quality by ensuring the adhesion between the first metal member and the second metal member during laser welding. Can be prevented or suppressed. In addition, the amount of penetration can be determined from the appearance after welding. Further, the change in the penetration depth during welding can be suppressed, which is suitable for long-time welding and continuous welding.

The schematic perspective view of the manufacturing apparatus of the joined body which concerns on embodiment of this invention. The plan view of FIG. Sectional drawing taken along the line III-III of FIG. Sectional drawing along line IV-IV of FIG. A perspective view of an example of a joined body. Top view of the first alternative of the joint. The schematic diagram of the irradiation pattern in the junction of FIG. 6A. Top view of the second alternative of the joint. The schematic diagram of the irradiation pattern in the junction of FIG. 7A. Top view of the third alternative of the joint. The schematic diagram of the irradiation pattern in the junction of FIG. 8A. Top view of the fourth alternative of the joint. The schematic diagram of the irradiation pattern in the junction of FIG. 9A. Top view of the fifth alternative of the joint. The schematic diagram of the irradiation pattern in the junction of FIG. 10A. Top view of the sixth alternative of the joint. Top view of the seventh alternative of the joint. Top view of the eighth alternative of the joint.

1 to 4 show a laser welding apparatus 1 for executing the laser welding method according to the embodiment of the present invention. FIG. 5 shows a bonded body 2 manufactured by laser welding by the laser welding apparatus 1.

Referring to FIG. 5, the joint 2 includes a blank material (first metal member) 3 and a reinforcing material (second metal member) 4. In the present embodiment, the blank material 3 and the reinforcing material 4 are both made of carbon steel, which is an example of a magnetic material.

In the present embodiment, both the blank material 3 and the reinforcing material 4 are rectangular or elongated strip-shaped plates having a substantially uniform thickness. The outer contour of the reinforcing material 4 in a plan view is smaller than the outer contour of the blank material 3 in a plan view. That is, the width Wr of the reinforcing material 4 is narrower than the width Wb of the blank material 3, and the length Lr of the reinforcing material 4 is shorter than the length Lb of the blank material 3.

The reinforcing material 4 is superposed on the blank material 3 and fixed to the blank material 3 by laser welding. In the present embodiment, the joint body 2 includes a joint portion 6 composed of one continuous linear weld mark or a welded portion 5. The blank material 3 and the reinforcing material 4 are joined to each other by the joint portion 6. The joint portion 6 in the present embodiment has a so-called zigzag shape, and the linear first portion 6a extending inclined with respect to the longitudinal direction and the width direction of the blank material 3 and the blank at different angles from the first portion 6a. It is composed of alternating repetitions with a linear second portion 6b extending inclined with respect to the longitudinal direction and the width direction of the material 3. The joint portion 6 shown in FIG. 5 is only an example, and there are various alternatives to the specific form of the joint portion 6.

Referring to FIGS. 1 to 4, the laser welding device 1 includes a table 11, a magnetic field generator 12, a cooling device 13, a laser oscillation system 14, a moving device 15, and a control device 16.

The table 11 includes an upper surface 11a which is a flat surface. As will be described later, the blank material 3 on which the reinforcing material 4 is placed is placed on the upper surface 11a of the table 11.

The table 11 in this embodiment is made of mild steel except for the copper plate 17 described later. The table 11 may be made of a non-magnetic material or a magnetic material. When the table 11 is made of a magnetic material, the degree of concentration of the magnetic field generated by the magnetic field generator 12 described later on the blank material 3 and the reinforcing material 4 on the table 11 can be increased.

The table 11 is provided with a groove or a recess 11b that is recessed from the upper surface 11a. The recess 11b in the present embodiment is a rectangular parallelepiped space, which is defined by a pair of short side walls 11c facing each other, a pair of long side walls 11d facing each other, and a bottom wall 11e, and an upper end facing the bottom wall 11e. It constitutes an opening 11f that opens on the upper surface 11a.

The outer contour of the recess 11b in a plan view is rectangular and smaller than the outer contour of the blank material 3 in a plan view, but larger than the outer contour of the reinforcing material 4 in a plan view. That is, the width Wc of the recess 11b is narrower than the width Wb of the blank material 3, but wider than the width Wr of the reinforcing material 4. Further, the length Lc of the recess 11b is shorter than the length Lb of the blank material 3, but longer than the length Lr of the reinforcing material 4.

A copper plate 17 is removably arranged at the bottom of the recess 11b. That is, the surface of the bottom wall 11e that defines the recess 11b is made of copper.

The magnetic field generator 12 is arranged below the table 11. The magnetic field generator 12 in the present embodiment includes a plurality of electromagnets 18. The magnetic field generator 12 may include a permanent magnet instead of the electromagnet 18. The blank material 3 and the reinforcing material 4 are attracted to and held by the upper surface 11a of the table 11 by the magnetic attraction force generated by the magnetic field generated by the magnetic field generator 12.

The cooling device 13 cools the table 11 during laser welding. The cooling device 13 in the present embodiment includes a refrigerant flow path 11g provided in the table 11 and a refrigerant supply device 19 for supplying and circulating the temperature-controlled refrigerant to the refrigerant flow path 11g.

The laser oscillation system 14 includes elements necessary for generating laser light, such as a laser oscillation element, a drive circuit, and an optical system. The laser beam 21 is emitted downward from the laser oscillation system 14.

The moving device 15 moves the laser oscillation system 14. The laser oscillation system 14 is fixed to the movable arm 22 included in the moving device 15 in the present embodiment in a posture in which the laser beam 21 faces downward. The movable arm 22 moves the laser oscillation system 14 in two directions in the horizontal plane, that is, in the X direction and the Y direction so that the irradiation position of the laser beam 21 moves along the joint portion 6.

The control device 16 comprehensively controls the operation of various elements of the laser welding device 1, including the magnetic field generator 12, the cooling device 13, and the laser oscillation system 14.

Hereinafter, the operation of the laser welding apparatus 1, that is, the laser welding method executed by the laser welding apparatus 1 will be described.

First, the blank material 3 is placed on the upper surface 11a of the table 11 in a state where the reinforcing material 4 is placed on the blank material 3, that is, in a state where the lower surface of the reinforcing material 4 is overlapped on the upper surface of the blank material 3. That is, the lower surface of the blank material 3 is overlapped with the upper surface 11a of the table 11. At this time, the magnetic field generator 12 does not generate a magnetic field.

The blank material 3 is positioned on the upper surface 11a of the table 11 so that the blank material 3 closes the opening 11f of the recess 11b and the reinforcing material 4 is located above the recess 11b. Specifically, referring to FIG. 2, the entire outer contour (edge defining the opening 11f) in the plan view of the recess 11b is arranged in the region surrounded by the outer contour in the plan view of the blank material 3. .. Further, the entire outer contour of the reinforcing material 4 in the plan view is arranged in the region surrounded by the outer contour of the recess 11b in the plan view.

Next, the magnetic field generator 12 is activated to generate a magnetic field. The blank material 3 and the reinforcing material 4 are attracted to the table 11 by the magnetic attraction force generated by the magnetic field generated by the magnetic field generator 12. As a result, the blank material 3 is in close contact with the upper surface 11a of the table 11, and the reinforcing material 4 is in close contact with the upper surface of the blank material 3. Specifically, the lower surface of the blank material 3 is in close contact with the upper surface 11a of the table 11 except for the portion blocking the opening 11f of the recess 11b. Further, the entire lower surface of the reinforcing material 4 is in close contact with the upper surface of the blank material 3. As described above, the blank material 3 is held on the table 11 by the magnetic field generated by the magnetic field generator 12, and the reinforcing material 4 is temporarily fixed to the blank material 3.

Next, the laser oscillation system 14 is moved along a predetermined path by the moving device 15, and the reinforcing material 4 is irradiated with the laser beam 21 from the laser oscillation system 14 so that the above-mentioned joint portion 6 is formed. In addition, the reinforcing material 4 is laser-welded to the blank material 3. The table 11 is cooled by the cooling device 13 during the laser welding, that is, during the irradiation of the laser beam 21 from the laser oscillation system 14.

In the present embodiment, the irradiation conditions of the laser beam 21 from the laser oscillation system 14 are set so that the penetration depth reaches the lower surface of the blank material 3, that is, through welding.

The above laser welding method has the following advantages.

First, the blank material 3 and the reinforcing material 4 are attracted to the table 11 by the magnetic attraction force generated by the magnetic field generated by the magnetic field generator 12. Therefore, high adhesion between the upper surface of the blank material 3 and the reinforcing material 4 is ensured. That is, the entire lower surface of the reinforcing material 4 uniformly adheres to the upper surface of the blank material 3. By ensuring such high adhesion, welding defects and the like can be prevented or suppressed, and welding quality is improved.

In the present embodiment, not only the reinforcing material 4 but also the blank material 3 is made of a magnetic material. Assuming that the blank material 3 directly placed on the upper surface 11a of the table 11 is a magnetic material, the lower surface of the blank material is entirely covered with the table 11 except for the portion covering the recess 11b due to the magnetic force generated by the magnetic force generator 12. It is constrained by the upper surface 11a. As a result, the blank material 3 is held on the upper surface 11a of the table 11 in a state where deformation such as warpage is suppressed and has a high flatness, and the adhesion between the blank material 3 and the reinforcing material 4 is further improved.

Secondly, since the reinforcing material 4 is located above the recess 11b as described above, through welding is performed without causing problems such as damage to the upper surface 11a of the table 11 and joining of the blank material 3 to the table 11. Is possible. Since the keyhole penetrates through the penetration welding, it is possible to prevent or suppress the occurrence of welding defects such as blowholes. Further, since it is through welding, the amount of penetration can be determined from the appearance after welding.

Thirdly, since the lower surface of the blank material 3 in the portion where the reinforcing material 4 is placed does not adhere to the upper surface 11a of the table 11 but covers the recess 11b, the welding heat is effectively dissipated. NS. As a result, it is possible to suppress the change in the penetration depth during welding due to the temperature rise of the blank material 3 and the reinforcing material 4, and it is suitable for long-time welding and continuous welding. Further, since the table 11 is cooled by the cooling device 13, the welding heat can be dissipated more effectively.

Fourth, since the reinforcing material 4 is temporarily fixed to the blank material 3 by the magnetic attraction force generated by the magnetic field generated by the magnetic field generator 12, it is not necessary to use a jig or the like for clamping. Further, unlike the case where the reinforcing material 4 is temporarily fixed to the blank material 3 by a clamp using a jig, the entire surface of the reinforcing material 4 can be irradiated with the laser beam 21. That is, the joint portion 6 can be formed on the entire surface of the reinforcing material.

When spatter occurs during laser welding, it adheres to the surface of the copper plate 17 arranged at the bottom of the recess 11b. The copper plate 17 to which the spatter is attached can be taken out from the recess 11b to remove the spatter, or can be replaced with a new copper plate 17. This makes it possible to suppress changes in welding characteristics due to adhesion of spatter.

The blank material 3 may be a non-magnetic material. In this case, the reinforcing material 4 made of a magnetic material is attracted to the upper surface 11a of the table 11 by the magnetic attraction force generated by the magnetic field generated by the magnetic field generator 12, and accordingly, between the table 11 and the reinforcing material 4. The blank material 3 interposed therebetween is also attracted to the upper surface 11a of the table 11.

The recess 11b in this embodiment has a bottom wall 11e. However, the recess 11b may be in the form of penetrating the table 11 in the thickness direction. In this case, the upper surface of the magnetic generator 12 constitutes the bottom portion of the recess 11b, and the copper plate 17 is placed in this portion.

6A to 13 show various alternatives of the bonded body 2 that can be manufactured by laser welding by the laser welding apparatus 1. In these alternatives, the elements common to the junction 2 of the embodiment shown in FIG. 5 are designated by the same reference numerals. These alternative joints 2 differ from the joint 2 (FIG. 5) shown in FIG. 5 in the form of the joint 6 composed of the weld marks or the weld 5.

In the joint portion 6 shown in FIG. 6A, the closed figure (irradiation pattern 31) drawn by the irradiation position P1 of the laser beam 21 shown in FIG. 6B is in the moving direction indicated by the arrow MD from one end side to the other end side of the reinforcing material 4. It can be obtained by setting.

The irradiation pattern 31 of FIG. 6B has two wedge-shaped portions having a shape that widens in the direction of the movement direction MD, that is, an outer wedge-shaped portion 31b and an inner wedge-shaped portion 31b arranged inside the outer wedge-shaped portion 31b. It is provided with a shape portion 31c.

The outer wedge-shaped portion 31b includes a pair of hypotenuse portions 31d inclined with respect to the movement direction MD as a whole, and an arc-shaped tip portion 31e connecting these hypotenuse portions 31d. Each of the hypotenuse portions 31d has a linear first portion 31f having one end connected to the tip portion 31e, a linear second portion 31g having one end connected to the other end of the first portion 31f, and a second portion 31g. It has a third portion 31h to which one end is connected to the other end of the. In this example, the angle with respect to the moving direction MD is larger in the order of the second portion 31g, the first portion 31f, and the third portion 31h, and the third portion 31h extends in substantially the same direction as the moving direction MD. Further, in this example, the length of the second portion 31g is shorter than that of the first portion 31f and the second portion 31h.

The inner wedge-shaped portion 31c includes a pair of linear hypotenuse portions 31i that are inclined with respect to the moving direction MD, and an arc-shaped tip portion 31j that connects these hypotenuse portions 31i. The tip portion 31j of the inner wedge-shaped portion 31c generally overlaps with the tip portion 31e of the outer wedge-shaped portion 31b. Each of the hypotenuse portions 31i has a linear first portion 31m having one end connected to the tip portion 31j, a linear second portion 31n having one end connected to the other end of the first portion 31m, and a second portion 31n. It has a third portion 31o to which one end is connected to the other end of the.

The individual hypotenuse portions 31d of the outer wedge-shaped portion 31b are connected to the adjacent hypotenuse portions 31i of the inner wedge-shaped portion 31c via an arc-shaped reversing portion 31k.

Referring to FIG. 6A together, in the joint portion 6 obtained by the irradiation pattern 31 of FIG. 6B, the polygonal linear portion 6c having two curved portions corresponding to the hypotenuse portions 31i of the inner wedge-shaped portion 31c of the irradiation pattern 31. And the bent line-shaped portion 6d having two bent portions corresponding to the hypotenuse portion 31d of the outer wedge-shaped portion 31b are alternately provided, and the portions 6c and the portion 6d adjacent to each other are the portions 6e corresponding to the inverted portion 31k. Is connected by. The joint portion 6 of FIG. 6A is provided so that the portions 6c, 6d, and 6e do not overlap each other.

The joint portion 6 shown in FIG. 7A is obtained by moving the welding pattern 31 shown in FIG. 7B in the moving direction MD.

In the welding pattern 31 of FIG. 7B, the hypotenuse portion 31d of the outer wedge-shaped portion 31b has a linear first portion 31f having one end connected to the tip portion 31e and a third portion extending substantially in the same direction as the moving direction MD. It is composed of a portion 31h. Further, the hypotenuse portion 31i of the inner wedge-shaped portion 31c is linear. Other shapes of the welding pattern 31 of FIG. 7B are the same as those of FIG. 6B. In FIG. 7B, the same reference numerals are given to the elements common to those in FIG. 6B.

Referring to FIG. 7A together, in the joint portion 6 obtained by the irradiation pattern 31 of FIG. 7B, the linear portion 6f corresponding to the hypotenuse portion 31i of the inner wedge-shaped portion 31c of the irradiation pattern 31 and the outer wedge-shaped portion 31b. 6g of a polygonal line having a bent portion corresponding to the hypotenuse portion 31d of the above is alternately provided, and the portions 6f and the portion 6g adjacent to each other are connected by a portion 6h corresponding to the inverted portion 31k. The joint portion 6 of FIG. 7A is provided so that the portions 6f, 6g, and 6h do not overlap each other.

The joint portion 6 shown in FIG. 8A is obtained by moving the irradiation pattern 31 shown in FIG. 8B in the moving direction MD. The irradiation pattern 31 shown in FIG. 8B is the same as the irradiation pattern 31 of FIG. 6B, except that the hypotenuse portion 31i of the inner wedge-shaped portion 31c is linear. Therefore, the joint portion 6 shown in FIG. 8A has a linear portion 6i corresponding to the hypotenuse portion 31i of the inner wedge-shaped portion 31c of the irradiation pattern 31 and a bent portion corresponding to the hypotenuse portion 31d of the outer wedge-shaped portion 31b. The bent line-shaped portions 6j provided at the portions are alternately provided, and the portions 6i and the portions 6j adjacent to each other are connected by a portion 6g corresponding to the inversion portion 31k. The joint portion 6 of FIG. 8A is provided so that the portions 6i, 6j, and 6k do not overlap each other. In FIGS. 8A and 8B, the same elements as those in FIGS. 6A and 6B are designated by the same reference numerals.

The joint portion 6 shown in FIG. 9A is obtained by moving the irradiation pattern 31 shown in FIG. 9B in the moving direction MD. The irradiation pattern 31 shown in FIG. 9B is the same as that of FIG. 8B, but the moving speed of the virtual irradiation position P1 on the irradiation pattern 31 is set to be larger than the moving speed of the moving direction MD of the irradiation pattern 31. doing. Therefore, in the joint portion 6 shown in FIG. 9A, an intersection portion 6m where the welded portions 5 intersect is formed in the portion 6g corresponding to the inversion portion 31k. In FIGS. 9A and 9B, the same elements as those in FIGS. 8A and 8B are designated by the same reference numerals.

The joint portion 6 shown in FIG. 10A is obtained by moving the irradiation pattern 31 shown in FIG. 10B in the moving direction MD. The irradiation pattern 31 of FIG. 10B has four curved protrusions 31a having the same shape arranged at equal intervals (intervals of 90 degrees). Referring to FIG. 10A together, the joint portion 6 obtained by this irradiation pattern has a network-like structure in which the portions 6n corresponding to the protrusions 31a are provided two-dimensionally and continuously while overlapping with each other. , A plurality of intersections 6o are two-dimensionally distributed.

In the joint portion 6 shown in FIG. 11, a plurality of first linear portions 6p having the same length extending in the longitudinal direction of the blank material 3 and a plurality of second linear portions having the same length extending in the lateral direction of the blank material 3 The portions 6q are provided alternately. The joint portion 6 has an elongated crank-like shape due to the plurality of linear portions 6p and the second linear portion 6q. That is, the plurality of first linear portions 6p are arranged at regular intervals in the lateral direction of the blank material 3, and the ends of the individual first linear portions 6p pass through the second linear portion 6q. It is connected to another adjacent first linear portion 6p.

In the joint portion 6 shown in FIG. 12, a plurality of first linear portions 6p extending in the longitudinal direction of the blank material 3 and a plurality of second linear portions 6q extending in the lateral direction of the blank material 3 are alternately provided. , It has a spiral shape as a whole.

In the joint portion 6 shown in FIG. 13, a plurality of first linear portions 6p extending in the longitudinal direction of the blank material 3 and a plurality of second linear portions extending in the lateral direction of the blank material 3 are formed in the joint portion 6 as in FIG. The portions 6q are alternately provided, and have a spiral shape as a whole. Further, a linear first inclined portion 6r extending inclined with respect to the longitudinal direction and the width direction of the blank material 3 from the end portion of the first linear portion 6p constituting the innermost end of the spiral shape, and the first. A linear second inclined portion 6s extending inclined with respect to the longitudinal direction and the width direction of the blank material 3 at an angle different from the inclined portion 6r is alternately and repeatedly provided. The first and second inclined portions 6r and 6s have a zigzag shape. Further, the individual first inclined portion 6r and the individual second inclined portion 6s intersect with the plurality of first linear portions 6p, whereby the intersecting portion 6t is formed.

1 Laser welding equipment 2 Joined body 3 Blank material (first metal member)
4 Reinforcing material (second metal member)
5 Welded part 6 Joint part 6a 1st part 6b 2nd part 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6n part 6m, 6o, 6t Intersection part 6p 1st straight part 6q 2nd Linear part 6r 1st inclined part 6s 2nd inclined part 11 table 11a upper surface 11b recess 11c short side wall 11d long side wall 11e bottom wall 11f opening 11g refrigerant flow path 12 magnetic field generator 13 cooling device 14 laser oscillation system 15 moving device 16 control Device 17 Copper plate 18 Electromagnet 19 Refrigerant supply device 21 Laser light 22 Movable arm 31 Irradiation pattern 31a Protruding part 31b Outer wedge-shaped part 31c Inner wedge-shaped part 31d, 31i Oblique side part 31e, 31j Tip part 31f, 31m First part 31g, 31n 2nd part 31h, 31o 3rd part 31k Inversion part MD Moving direction P1 Irradiation position

Claims (7)

A laser welding method in which a first metal member and a second metal member made of a magnetic material are welded together.
A table having a recess recessed from the upper surface and a magnetic field generator arranged below the table are prepared.
The first metal member is placed on the upper surface of the table, the second metal member is placed on the first metal member, and the second metal member is positioned above the recess.
The second metal member is attracted to the table together with the first metal member by the magnetic attraction force generated by the magnetic field generated by the magnetic field generator.
While maintaining the state in which the first and second metal members are attracted to the table by the magnetic attraction, the second metal member is irradiated with laser light from the laser oscillation system, and the first metal member and the first metal member are described. A laser welding method for forming a welded portion to which a second metal member is joined. The laser welding method according to claim 1, wherein the irradiation condition of the laser beam is set so that the penetration depth reaches the lower surface of the first metal member. Claim 1 or claim that the outer contour of the concave portion in a plan view is smaller than the outer contour of the first metal member in a plan view and larger than the outer contour of the second metal member in a plan view. 2. The laser welding method according to 2. The laser welding method according to any one of claims 1 to 3, wherein a copper plate is removably arranged at the bottom of the recess. The laser welding method according to any one of claims 1 to 4, wherein the table is cooled during irradiation with the laser beam. The laser welding method according to any one of claims 1 to 5, wherein the first metal member is made of a magnetic material. A laser welding device that welds a first metal member and a second metal member made of a magnetic material.
The first metal member on which the second metal member is placed is placed on the upper surface so as to have a recess recessed from the upper surface and the second metal member is located above the recess. Table and
A magnetic field generator, which is arranged below the table and generates a magnetic field that attracts the second metal member to the table by magnetic attraction together with the first metal member.
A laser welding apparatus including a laser oscillation system that irradiates the second metal member with a laser beam.

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