Method for joining metal members and structure for joining metal members

Abstract

To provide a metallic member joining method capable of suppressing the increasing size and complication of a device for joining a metallic member, a member joining method, and a metallic member joining structure.SOLUTION: A metallic member joining method includes a step S4 of joining first and second metallic members 11 and 12 together by melting either of the first and second metallic members 11 and 12 without pushing the second metallic member 12 in the state of inserting a shank 12a of the second metallic member 12 into a through-hole 11 of the first metallic member 11.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a method for joining metal members. Law and metal member joining structure. [Background technology]

[0002] 2. Description of the Related Art Conventionally, a method for joining metal members is known (see, for example, Patent Document 1).

[0003] The above-mentioned Patent Document 1 discloses a method for joining metal members, which joins a first joining member made of metal and a second joining member made of metal. The method for joining metal members includes a step of forming a welding boss on the first joining member. The method for joining metal members includes a step of forming an insertion hole into which the welding boss can be inserted on the second joining member. The method for joining metal members includes a step of inserting the welding boss into the insertion hole and then pressing a heated thermal crimping tool against the tip of the welding boss protruding from the insertion hole. In this way, in the method for joining metal members of the above-mentioned Patent Document 1, the welding boss softened by heating with the thermal crimping tool is shaped, thereby joining the first joining member and the second joining member made of metal. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2018-83329 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the joining method of metal members of Patent Document 1, when the step of pressing a heated thermal crimping tool against the tip of the welding boss protruding from the insertion hole is performed, if the first joining member and the second joining member are made of a material with low rigidity, it is necessary to clamp (sandwich and fix in position) the first joining member and the second joining member in order to prevent the welding boss from moving due to the pressing of the thermal crimping tool. In this case, the joining method of metal members of Patent Document 1 requires a dedicated clamping device for clamping the first joining member and the second joining member. Therefore, in the joining method of metal members of Patent Document 1, the device for joining metal members becomes large and complicated by the clamping device, so it is desired to suppress the increase in size and complexity of the device for joining metal members. Furthermore, when the first and second joining members are joined by entirely melting both the first and second joining members and welding them alone, the area of ​​the compounds (intermetallic compounds) generated by welding the first and second joining members becomes large, which causes a problem in that the joining strength between the first and second joining members is reduced due to the compounds.

[0006] The present invention has been made to solve the above-mentioned problems, and one object of the present invention is to provide a method for joining metal members that can suppress an increase in size and complexity of an apparatus for joining the metal members. Law and to provide a metal member joining structure. [Means for solving the problem]

[0007] In order to achieve the above object, a method for joining metal members in a first aspect of the present invention includes a first metal member preparation step of preparing a first metal member made of metal having a through hole; a second metal member preparation step of preparing a second metal member separate from the first metal member having a shaft portion insertable into the through hole of the first metal member; an insertion step of inserting the shaft portion of the second metal member into the through hole of the first metal member; and, with the shaft portion of the second metal member inserted into the through hole of the first metal member, melting either the first metal member or the second metal member without pressing the second metal member. and using an engagement portion formed by melting and solidifying either the molten first metal member or the molten second metal member into a groove portion or a tapered portion between the inner surface of the through hole and the shaft portion,and a joining step of joining the first metal member and the second metal member.

[0008] In the method for joining metal members according to the first aspect of the present invention, as described above, in a state in which the shaft portion of the second metal member is inserted into the through hole of the first metal member, one of the first metal member and the second metal member is melted without pressing the second metal member. and using an engagement portion formed by melting and solidifying either the molten first metal member or the molten second metal member into a groove portion or a tapered portion between the inner surface of the through hole and the shaft portion, A joining step is provided for joining the first metal member and the second metal member. As a result, since external force is unlikely to be applied to the second metal member, even if the first metal member and the second metal member are made of a material with low rigidity, there is no need to melt either the first metal member or the second metal member while the second metal member is sandwiched and fixed in position. As a result, the size and complexity of the device for joining the metal members can be suppressed by not providing a dedicated clamp device for sandwiching and fixing the second metal member. In addition, since both the first metal member and the second metal member are not melted overall, it is possible to suppress an increase in the area of ​​the compound (intermetallic compound) generated due to welding the first metal member and the second metal member. As a result, it is possible to suppress a decrease in the joint strength between the first metal member and the second metal member caused by the compound.

[0009] In the method for joining metal members according to the above-mentioned first aspect, the joining step preferably includes a step of melting and joining either the first metal member or the second metal member by a high-density energy beam or a high-temperature heat source without pressing the second metal member.

[0010] With this configuration, it is possible to melt either the first metal member or the second metal member from a position away from the second metal member by the high-density energy beam, so that it is possible to prevent a load from being applied to the second metal member when melting either the first metal member or the second metal member. Also, a high-temperature heat source having a high heat source temperature can melt either the first metal member or the second metal member by merely coming into slight contact with either the first metal member or the second metal member, so it is possible to reduce the load applied to the second metal member when melting either the first metal member or the second metal member.

[0011] In the above-mentioned method for joining metal members according to the first aspect, the second metal member preparation step preferably includes a step of preparing a rod-shaped second metal member having a shaft portion with a tip portion that is thinner than other portions.

[0012] With this configuration, the shaft portion can be formed by cutting or pressing, and therefore the processing method for forming the shaft portion can be simplified.

[0013] The aforementioned method for joining metal members according to the first aspect preferably further comprises the step of forming a non-circular anti-rotation portion in at least one of the through hole or the shaft portion for preventing rotation of the shaft portion relative to the through hole.

[0014] With this configuration, the rotation of the shaft portion within the through hole can be restricted by the anti-rotation portion, so that the first metal member and the second metal member can be positioned in the rotation direction of the shaft portion.

[0015] In the above-mentioned method for joining metal members according to the first aspect, the joining step preferably includes a step of irradiating a high-density energy beam to melt both the first metal member and the second metal member to partially join the first metal member and the second metal member by welding, and melting either the first metal member or the second metal member to join the first metal member and the second metal member.

[0016] With this configuration, the rotation of the shaft portion within the through hole can be restricted by the areas where the first metal member and the second metal member are partially welded together, so that the first metal member and the second metal member can be joined in a way that prevents them from moving in the rotational direction of the shaft portion.

[0017] In the above-mentioned method for joining metal members using a high-density energy beam, the joining step preferably includes a step of melting and joining either the first metal member or the second metal member by a laser as a high-density energy beam, without pressing the second metal member.

[0018] With this configuration, either the first metal member or the second metal member can be melted by a simple method, thereby making it possible to prevent the device for joining the metal members from becoming complicated.

[0019] In the above-described method for joining metal members according to the first aspect, the second metal member is preferably a coil inserted into a slot provided in the stator, the shaft portion being a coil end of the coil protruding outside the slot of the stator in the axial direction, and the joining step includes a step of melting and joining either the stator coil or the stator busbar without pressing the stator coil, with the shaft portion of the stator coil as the second metal member inserted into a through hole of the stator busbar as the first metal member.

[0020] With this configuration, external force is unlikely to be applied to the stator coil, so there is no need to melt either the stator busbar or the stator coil while the stator coil is clamped and fixed in position. As a result, there is no need to provide a dedicated clamp device for clamping and fixing the stator coil in position, which makes it possible to prevent the device for joining metal members from becoming too large.

[0023] The first aspect of this invention 2The metal member joining structure in this aspect includes a first metal member made of a metal and having a through hole formed therein, and a second metal member including a shaft portion inserted into the through hole of the first metal member and provided separately from the first metal member, the shaft portion being: A tapered portion between the inner surface of the through hole of the first metal member and the shaft portion is The tip is melted and solidified. The engagement portion formed The second metal member has Using the engagement part The first metal member is engaged with the second metal member, and when viewed from the direction in which the shaft portion is inserted, the first metal member and the second metal member are joined via a partially welded welded portion.

[0024] The first aspect of this invention 2 In the metal member joining structure in this aspect, as described above, the first metal member and the second metal member are partially joined when viewed from the insertion direction of the shaft portion. This makes it possible to restrict rotation of the shaft portion within the through hole, thereby obtaining a metal member joining structure that can join the first metal member and the second metal member in a manner that prevents them from moving in the rotation direction of the shaft portion.

[0025] In the method for joining metal members according to the first aspect, the following configuration is also possible.

[0026] (Additional note 1) That is, in the method for joining metal members according to the above-mentioned aspect, the method further includes a step of forming a tapered portion at the tip of the through hole of the first metal member, the tapered portion expanding in a direction perpendicular to the insertion direction as it approaches the insertion direction, and the joining step includes a step of melting the second metal member and pouring a portion of the molten second joining member into the tapered portion in the through hole.

[0027] With this configuration, the molten second metal member can easily flow deep into the through hole, so that the space between the second metal member and the through hole can be easily filled with the molten second metal member.

[0028] (Additional note 2) In the above-mentioned method for joining metal members including the second metal member preparation step, the insertion step includes a step of inserting the shaft portion of the second metal member into the through hole of the first metal member until the end face on the shaft portion side of the other part of the rod-shaped second metal member abuts against the first metal member.

[0029] With this configuration, the first metal member and the second metal member can be joined by sandwiching the first metal member between the end face on the shaft side of the other portion of the rod-shaped second metal member and the shaft portion of the second metal member melted and solidified in the through hole. As a result, the first metal member and the second metal member are joined by sandwiching the first metal member between the end face on the shaft side of the other portion of the rod-shaped second metal member and the shaft portion of the second metal member melted and solidified in the through hole, so that the first metal member and the second metal member can be firmly joined.

[0030] (Additional note 3) In the method for joining metal members according to the above first aspect, the first metal member preparation step further includes a step of forming a groove portion in the through hole that is recessed in a direction perpendicular to an insertion direction in which the shaft portion of the second metal member is inserted into the through hole of the first metal member, and the joining step includes a step of melting the second metal member and pouring a portion of the molten second metal member into the groove portion in the through hole.

[0031] With this configuration, a portion of the second metal member solidified in the groove portion can position the first metal member and the second metal member in both the insertion direction and the direction opposite to the insertion direction, making it easier to process the second metal member compared to a case in which positioning structures for the insertion direction and the direction opposite to the insertion direction are formed separately in the first metal member and the second metal member.

[0032] (Additional note 4) In the method for joining metal members, which includes the step of forming a shaft portion thinner than the other portions, the inserting step includes a step of inserting and fitting the shaft portion of the second metal member into the through hole of the first metal member, and the second metal member preparing step includes a step of forming an elongated portion by making the portion of the shaft portion thinner than the portion that fits into the through hole.

[0033] With this configuration, the elongated portion is thinner than the other portions and can be melted more easily, thereby improving the efficiency of the process of melting the shaft portion.

[0034] (Additional note 5) In the above-mentioned method for joining metal members using a high-density energy beam, the second metal member preparation step includes a recess formed by recessing an end face on the insertion direction side along which the shaft portion of the second metal member is inserted into the through hole of the first metal member in a direction opposite to the insertion direction, and the joining step includes a step of joining the second metal member by irradiating a laser as a high-density energy beam onto the recess.

[0035] With this configuration, the laser can be diffused inside the recess of the second metal member, so that the energy of the laser can be reliably absorbed by the second metal member. As a result, even if a laser with low absorption rate for the second metal member is used, the second metal member can be melted. [Brief description of the drawings]

[0036] [Figure 1] 1 is a perspective view showing a motor to which the methods for joining metal members according to the first to seventh embodiments are applied. [Diagram 2] FIG. 2 is a perspective view of a cross section taken along line 101-101 in FIG. [Diagram 3] FIG. 2 is a schematic cross-sectional view taken along line 101-101 in FIG. [Figure 4] 4 is a flowchart showing a method for joining metal members according to the first embodiment. [Diagram 5]4A to 4C are cross-sectional views showing a step of forming a shaft portion of a segment coil and a through hole in a busbar ring in the method for joining metal members according to the first embodiment. [Figure 6] 4 is a cross-sectional view showing a step in which the shaft portion of the segment coil is inserted into the through hole of the busbar ring in the method for joining metal members of the first embodiment. FIG. [Figure 7] 2 is a plan view showing a state in which the shaft portion of the segment coil is inserted into the through hole of the busbar ring in the joining method of metal members of the first embodiment. FIG. [Figure 8] 4 is a cross-sectional view showing a process of irradiating a laser onto a shaft portion of a segment coil in the method for joining metal members according to the first embodiment. FIG. [Figure 9] 1 is a plan view showing the state in which the molten shaft portion of the segment coil has solidified in the method for joining metal members of the first embodiment. FIG. [Figure 10] 11 is a cross-sectional view showing a segment coil and a bus bar ring joined by a method for joining metal members of a second embodiment. FIG. [Figure 11] 10 is a flowchart showing a method for joining metal members according to a second embodiment. [Figure 12] 11 is a cross-sectional view showing a step of forming a shaft portion of a segment coil and a through hole of a bus bar ring in a joining method of metal members according to a second embodiment. FIG. [Figure 13] 11 is a cross-sectional view showing a step in which the shaft portion of the segment coil is inserted into the through hole of the busbar ring in the method for joining metal members of the second embodiment. FIG. [Figure 14] 13 is a cross-sectional view showing a step of irradiating a bus bar ring with a laser in the method for joining metal members according to the second embodiment. FIG. [Figure 15] 13 is a plan view showing a segment coil and a bus bar ring joined by the method for joining metal members of a third embodiment. FIG. [Figure 16] 16(A) to 16(G) are plan views showing modified examples of a segment coil and a bus bar ring joined by the method for joining metal members according to the third embodiment. [Figure 17]10 is a flowchart showing a method for joining metal members according to a third embodiment. [Figure 18] 13 is a cross-sectional view showing a segment coil and a bus bar ring joined by a method for joining metal members according to a fourth embodiment. FIG. [Figure 19] 19(A) and 19(B) are cross-sectional views showing modified examples of a segment coil and a bus bar ring joined by the method for joining metal members according to the fourth embodiment. [Figure 20] 13 is a flowchart showing a method for joining metal members according to a fourth embodiment. [Figure 21] 13 is a plan view showing a segment coil and a bus bar ring joined by the method for joining metal members of a fifth embodiment. FIG. [Figure 22] 13 is a cross-sectional view showing a segment coil and a bus bar ring joined by the method for joining metal members of a fifth embodiment. FIG. [Figure 23] 13 is a flowchart showing a method for joining metal members according to a fifth embodiment. [Figure 24] 13 is a cross-sectional view showing a process of irradiating a laser onto a shaft portion of a segment coil in a method for joining metal members according to a fifth embodiment. FIG. [Diagram 25] 13 is a plan view showing the state in which the molten shaft portion of the segment coil has solidified in the method for joining metal members of the fifth embodiment. FIG. [Figure 26] 13 is a flowchart showing a method for joining metal members according to a sixth embodiment. [Figure 27] 13 is a cross-sectional view showing a step of forming a shaft portion of a segment coil and a through hole of a bus bar ring in a joining method of metal members according to a sixth embodiment. FIG. [Figure 28] A cross-sectional view showing a process of irradiating a laser to an elongated portion of a shaft of a segment coil in a method for joining metal members according to a sixth embodiment. [Figure 29] 13 is a flowchart showing a method for joining metal members according to a seventh embodiment. [Diagram 30]13 is a cross-sectional view showing a step of forming a shaft portion of a segment coil and a through hole of a bus bar ring in a joining method of metal members according to the seventh embodiment. FIG. [Diagram 31] A cross-sectional view showing a process of irradiating a laser onto a recess in the shaft portion of a segment coil in a method for joining metal members according to a seventh embodiment. [Diagram 32] 13 is a cross-sectional view showing a modified example of a segment coil and a bus bar ring joined by the method for joining metal members according to the first to seventh embodiments. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0037] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0038] [First embodiment] The configuration of a method for joining metal members will be described with reference to Figs. 1 to 9.

[0039] The following describes the configuration of a stator 1 provided in a motor 100, as shown in Fig. 1. Specifically, the motor 100 includes a stator 1 and a rotor (not shown).

[0040] As shown in FIG. 1 to FIG. 3, the stator 1 is a busbar ring. Gu 1 1 (An example of the "first metal member" and "bus bar" in the claims) And, segment carp Rule 1 2 (An example of the "second metal member," "second member," and "coil" in the claims.) and a slot 13. The bus bar ring 11 is made of aluminum.

[0041] As shown in Fig. 2 and Fig. 3, the busbar ring 11 has a through hole 11a for connecting the tip end of the segment coil 12 to the busbar ring 11. The through hole 11a penetrates the busbar ring 11 in the thickness direction. The through hole 11a has a tapered portion 111. In a direction A (an example of an "insertion direction" in the claims) in which a shaft portion 12a (described later) of the segment coil 12 is inserted into the through hole 11a of the busbar ring 11, the tapered portion 111 widens in a direction perpendicular to the direction A toward the tip of the through hole 11a of the busbar ring 11 in the direction A.

[0042] The segment coil 12 is formed of a different type of metal from the busbar ring 11. The segment coil 12 is formed of copper. The segment coil 12 is provided separately from the busbar ring 11. The segment coil 12 is formed in a rod shape. The segment coil 12 is a coil inserted into a slot 13 provided in the stator 1. The segment coil 12 has a shaft portion 12a. The shaft portion 12a is formed by making the tip portion of the rod-shaped segment coil 12 thinner than the other portion 12b. The shaft portion 12a is a coil end of the coil protruding outside the slot 13 of the stator 1 in the C direction (an example of the "axial direction" in the claims). The C direction is a direction parallel to the direction along the central axis of rotation Rc of the motor 100.

[0043] The shaft portion 12 a has an engagement portion 121 , a backup portion 122 , and a fitting portion 123 .

[0044] The engaging portion 121 is formed by melting the tip of the shaft portion 12a. The engaging portion 121 has a tapered shape in the A direction that expands in a direction perpendicular to the A direction toward the tip of the segment coil 12 in the A direction. The engaging portion 121 also has a portion that protrudes in the A direction from the tip of the through hole 11a in the A direction. The backup portion 122 is an end surface on the shaft portion 12a side of the other portion 12b other than the shaft portion 12a of the segment coil 12. The backup portion 122 is an abutment surface that abuts against the busbar ring 11. The fitting portion 123 is a portion between the engaging portion 121 and the fitting portion 123 of the segment coil 12. The fitting portion 123 is a portion that fits into the through hole 11a. The fitting portion 123 is fitted into the through hole 11a by clearance fit.

[0045] The slots 13 are grooves recessed into the inner circumferential surface 1a of the stator 1. The slots 13 extend along the direction C. In the slots 13, a portion of the segment coil 12 is disposed.

[0046] (Method of joining metal components) Hereinafter, the method for joining metal members according to the first embodiment will be described with reference to Fig. 4 to Fig. 9. The method for joining metal members is a method for joining the busbar ring 11 and the segment coil 12 in such a way that no load is applied to the segment coil 12.

[0047] In step S1, a busbar ring 11 having a through hole 11a with a tapered portion 111 is prepared (see FIG. 5). That is, step S1 includes a step of forming the through hole 11a in the metal busbar ring 11, and a step of forming, in the direction A, a tapered portion 111 that widens in a direction perpendicular to the direction A as it approaches the direction A at the tip of the through hole 11a of the busbar ring 11. The through hole 11a is formed by cutting. Note that step S1 is an example of a "first metal member preparation step" in the claims.

[0048] In step S2, a segment coil 12 having a shaft portion 12a that can be inserted into the through hole 11a of the busbar ring 11 is prepared separately from the busbar ring 11 (see FIG. 5). That is, in step S2, a segment coil 12 having a shaft portion 12a in which the tip portion of the segment coil 12 is made thinner than the other portion 12b is prepared. Also, in step S2, the shaft portion 12a that can be inserted into the through hole 11a of the busbar ring 11 is formed in the segment coil 12 separate from the busbar ring 11. In step S2, the shaft portion 12a is formed by making the tip portion of the rod-shaped segment coil 12 thinner than the other portion 12b. The shaft portion 12a is formed by cutting. Note that step S2 is an example of a "second metal member preparation step" in the claims.

[0049] In step S3, the shaft portion 12a of the segment coil 12 is fitted into the through hole 11a of the busbar ring 11 (see Figs. 6 and 7). Step S3 includes a step of inserting and fitting the shaft portion 12a of the segment coil 12 into the through hole 11a of the busbar ring 11. Step S3 includes a step of inserting the shaft portion 12a of the segment coil 12 into the through hole 11a of the busbar ring 11 until the end face (backup portion 122) on the shaft portion 12a side of the other part 12b of the rod-shaped segment coil 12 abuts against the busbar ring 11. Note that step S3 is an example of an "insertion step" in the claims.

[0050] In step S4, the shaft portion 12a of the segment coil 12 is irradiated with a laser L (an example of a "high density energy beam" in the claims) (see Figures 8 and 9). Here, the laser L is a green laser. As a result, the shaft portion 12a melts, and the molten shaft portion 12a flows into the space in which the tapered portion 111 of the through hole 11a is provided. Then, the molten shaft portion 12a in the space in which the tapered portion 111 is provided is cooled by the outside air and solidifies (see Figure 9). Note that step S4 is an example of a "joining step" in the claims.

[0051] That is, step S4 is a step of melting the segment coil 12 and joining the busbar ring 11 and the segment coil 12 without pressing the segment coil 12 with the shaft portion 12a of the segment coil 12 inserted into the through hole 11a of the busbar ring 11. Specifically, step S4 is a step of melting and joining the segment coil 12 by the laser L as a high-density energy beam without pressing the segment coil 12 by not abutting a melting portion having a laser L or the like with the segment coil 12. Thus, in step S4, the segment coil 12 and the segment coil 12 of the busbar ring 11 are melted.

[0052] After step S4, the method for joining metal members is completed.

[0053] (Effects of the first embodiment) In the first embodiment, the following effects can be obtained.

[0054] In the first embodiment, as described above, the method for joining metal members includes step S4 of melting the segment coil 12 without pressing the segment coil 12 in a state where the shaft portion 12a of the segment coil 12 is inserted into the through hole 11a of the busbar ring 11 to join the busbar ring 11 and the segment coil 12. As a result, since an external force is unlikely to be applied to the segment coil 12, even if the segment coil 12 and the busbar ring 11 are made of a material with low rigidity, it is not necessary to melt the segment coil 12 in a state where the segment coil 12 is sandwiched and fixed in position. As a result, it is possible to suppress the increase in size and complexity of the device for joining metal members by not providing a dedicated clamp device for sandwiching and fixing the segment coil 12 in position. In addition, since both the segment coil 12 and the busbar ring 11 are not melted as a whole, it is possible to suppress an increase in the area of ​​the compound (intermetallic compound) generated due to welding the segment coil 12 and the busbar ring 11. As a result, it is possible to suppress a decrease in the joint strength between the segment coil 12 and the busbar ring 11 caused by the compound.

[0055] In the first embodiment, as described above, the method for joining metal members includes step S4 of melting and joining the segment coil 12 by using the laser L (high-density energy beam) without pressing the segment coil 12. This allows the segment coil 12 to be melted by the laser L from a position away from the segment coil 12, so that no load is applied to the segment coil 12 when the segment coil 12 is melted.

[0056] In the first embodiment, as described above, the method for joining metal members includes step S2 of preparing a segment coil 12 having a shaft portion 12a in which the tip portion of the rod-shaped segment coil 12 is thinner than the other portions. This allows the shaft portion 12a to be formed by cutting or pressing, making it easier to process the shaft portion 12a.

[0057] In the first embodiment, as described above, the method for joining metal members includes step S4 of melting and joining the segment coil 12 with the laser L as a high-density energy beam without pressing the segment coil 12. This allows the segment coil 12 to be melted by a simple method, thereby preventing the device for joining the metal members from becoming complicated.

[0058] In the first embodiment, as described above, the segment coil 12 is a coil inserted into the slot 13 provided in the stator 1. The shaft portion 12a is a coil end of the coil protruding outside the slot 13 of the stator 1 in the C direction. The joining method of the metal members includes step S4 of melting and joining the segment coil 12 of the stator 1 without pressing the segment coil 12 of the stator 1 in a state where the shaft portion 12a of the segment coil 12 of the stator 1 is inserted into the through hole 11a of the busbar ring 11 of the stator 1. As a result, since an external force is unlikely to be applied to the segment coil 12 of the stator 1, there is no need to melt the segment coil 12 of the stator 1 in a state where the segment coil 12 of the stator 1 is sandwiched and fixed in position. As a result, the size of the device for joining the metal members can be suppressed by not providing a dedicated clamp device for sandwiching and fixing the segment coil 12 of the stator 1.

[0059] [Second embodiment] Next, a method for joining metal members according to a second embodiment will be described with reference to Fig. 10 to Fig. 14. In particular, unlike the method for joining metal members according to the first embodiment, in the method for joining metal members according to the second embodiment, a tapered portion 2120 is formed on the shaft portion 212a of the segment coil 212. Note that in the second embodiment, the same reference numerals are used for configurations similar to those in the first embodiment, and descriptions thereof will be omitted.

[0060] As shown in FIG. 10, the motor 200 includes a stator 201 and a rotor (not shown).

[0061] The stator 201 is a busbar ring. Gu 2 11 (An example of the "first metal member" and "bus bar" in the claims) And, segment carp Rule 2 12 (An example of the "second metal member," "second member," and "coil" in the claims.) It includes:

[0062] The bus bar ring 211 has a through hole 211a formed therein for connecting the tip end of the segment coil 212 to the bus bar ring 211. The through hole 211a has a tapered portion 2111.

[0063] The segment coil 212 has a shaft portion 212a. The shaft portion 212a has an engagement portion 2121, a backup portion 122, and a fitting portion 123.

[0064] The engaging portion 2121 has a tapered shape in the A direction that widens in a direction perpendicular to the A direction toward the tip of the segment coil 212 in the A direction. In addition, in the A direction, the position of the engaging portion 2121 is substantially the same as the position of the tip of the through hole 211a. Note that other configurations of the second embodiment are similar to those of the first embodiment, and therefore description thereof will be omitted.

[0065] (Method of joining metal components) Hereinafter, a method for joining metal members according to the second embodiment will be described with reference to Fig. 11 to Fig. 14. The method for joining metal members is a method for joining the bus bar ring 211 and the segment coil 212 without applying a load to the segment coil 212.

[0066] In step S201, a busbar ring 211 having a through hole 211a is prepared (see FIG. 12). That is, step S201 includes a step of forming the through hole 211a in the metal busbar ring 211. The through hole 211a is formed by cutting. In step S202, a segment coil 212 having a tapered shaft portion 212a that can be inserted into the through hole 211a of the busbar ring 211 is prepared (see FIG. 12). In step S202, the shaft portion 212a having a tapered engagement portion 2121 is formed in the segment coil 212. The shaft portion 212a is formed by cutting. Note that step S201 is an example of a "first metal member preparation step" in the claims. Also, step S202 is an example of a "second metal member preparation step" in the claims.

[0067] In step S3, the shaft portion 212a of the segment coil 212 is fitted into the through hole 211a of the busbar ring 211 (see FIG. 13). In step S204, a laser L (one example of the "high density energy beam" in the claims) is irradiated near the through hole 211a of the busbar ring 211 (see FIG. 14). Here, the laser L is a green laser. As a result, a portion of the busbar ring 211 near the through hole 211a is melted, and the molten busbar ring 211 flows into the space provided between the through hole 211a and the shaft portion 212a. Then, the molten busbar ring 211 in the space provided between the through hole 211a and the shaft portion 212a is cooled by the outside air and solidified (see FIG. 10). In this way, in step S204, the busbar ring 211 of the segment coil 212 and the busbar ring 211 is melted. After step S204, the joining method of metal members is completed. Step S204 is an example of the "joining step" in the claims.

[0068] (Effects of the second embodiment) In the second embodiment, the following effects can be obtained.

[0069] In the second embodiment, as in the first embodiment, the method for joining metal members includes step S204 of melting the busbar ring 211 to join the busbar ring 211 and the segment coil 212 without pressing the segment coil 212 in a state where the shaft portion 212a of the segment coil 212 is inserted into the through hole 211a of the busbar ring 211. This makes it possible to prevent the device for joining metal members from becoming larger and more complicated. Note that other effects of the second embodiment are similar to those of the first embodiment, and therefore description thereof will be omitted.

[0070] [Third embodiment] Next, a method for joining metal members according to a third embodiment will be described with reference to Figures 15 to 17. In particular, unlike the method for joining metal members according to the first embodiment, the method for joining metal members according to the third embodiment has a rotation prevention portion 3111 formed in a through hole 311a of a bus bar ring 311. Note that in the third embodiment, the same components as those in the first embodiment are denoted by the same reference numerals and description thereof will be omitted.

[0071] As shown in FIG. 15, a motor 300 includes a stator 301 and a rotor (not shown).

[0072] The stator 301 is a busbar ring. Gu 3 11 (An example of the "first metal member" and "bus bar" in the claims) And, segment carp Rule 1 2 (An example of the "second metal member," "second member," and "coil" in the claims.) It includes:

[0073] As shown in FIG. 15, the busbar ring 311 has a through hole 311a for connecting the tip of the segment coil 12 to the busbar ring 311. The through hole 311a penetrates the busbar ring 311 in the thickness direction. The through hole 311a has a rotation stopper 3111. The rotation stopper 3111 is configured to stop the rotation of the shaft portion 12a relative to the through hole 311a at the through hole 311a. The rotation stopper 3111 has a non-circular shape in a plan view. Specifically, the rotation stopper 3111 has a substantially rectangular shape in a plan view.

[0074] The anti-rotation portion 3111 has modified examples as shown in Figs. 16(A) to 16(G).

[0075] The anti-rotation portion 3111 shown in Fig. 16(A) to Fig. 16(C) is provided in the through hole 311a. The anti-rotation portion 3111 shown in Fig. 16(A) has a substantially elliptical shape in a plan view. The anti-rotation portion 3111 shown in Fig. 16(B) has a substantially groove shape in a plan view. Note that a plurality of the substantially groove-shaped anti-rotation portions 3111 may be provided in the through hole 311a. The anti-rotation portion 3111 shown in Fig. 16(C) has a plurality (two) substantially triangular grooves and a plurality (two) grooves in a plan view.

[0076] The anti-rotation portion 3111 shown in FIG. 16(D) to FIG. 16(G) is provided in a through hole 311a and a shaft portion 312a. The anti-rotation portion 3111 shown in FIG. 16(D) has a through hole 311a having a substantially rectangular shape and a shaft portion 312a having a substantially rectangular shape in a plan view. The anti-rotation portion 3111 shown in FIG. 16(E) has a through hole 311a having a substantially elliptical shape and a shaft portion 312a having a substantially rectangular shape in a plan view. The anti-rotation portion 3111 shown in FIG. 16(F) has a through hole 311a having a substantially groove shape and a shaft portion 312a having a substantially rectangular shape in a plan view. It has a substantially groove shape. The anti-rotation portion 3111 shown in FIG. 16(G) has a plurality (two) triangular grooves and a plurality (two) grooves in a plan view. The other configurations of the third embodiment are the same as those of the first embodiment, so the description will be omitted.

[0077] (Method of joining metal components) Hereinafter, a method for joining metal members according to the third embodiment will be described with reference to Fig. 17. The method for joining metal members is a method for joining a bus bar ring 311 and a segment coil 12 (312) together, which can prevent a load from being applied to the segment coil 12.

[0078] In step S301, a busbar ring 311 having through holes 311a with anti-rotation portions 3111 is prepared (see FIG. 15). That is, in step S301, through holes 311a with anti-rotation portions 3111 are formed in the busbar ring 311. Note that step S301 is an example of a "first metal member preparation step" in the claims. Here, the contents of steps S2 to S4 are the same as the contents of steps S2 to S4 in the first embodiment, and therefore description thereof will be omitted.

[0079] (Effects of the third embodiment) In the third embodiment, the following effects can be obtained.

[0080] In the third embodiment, similarly to the first embodiment, the method for joining metal members includes step S4 of melting the segment coil 12 (312) to join the busbar ring 311 and the segment coil 12 (312) without pressing the segment coil 12 (312a) in a state where the shaft portion 12a (312a) of the segment coil 12 (312) is inserted into the through hole 311a of the busbar ring 311. This makes it possible to prevent the device for joining metal members from becoming large and complicated.

[0081] In the third embodiment, as described above, the method for joining metal members includes step S1 of forming a non-circular anti-rotation portion 3111 that stops the rotation of the shaft portion 12a (312a) relative to the through hole 311a in at least one of the through hole 311a or the shaft portion 12a (312a). This allows the anti-rotation portion 3111 to restrict the rotation of the shaft portion 12a (312a) in the through hole 311a, so that the busbar ring 311 and the segment coil 12 (312) can be positioned in the rotation direction of the shaft portion 12a (312a). Note that other effects of the third embodiment are similar to those of the first embodiment, so a description thereof will be omitted.

[0082] [Fourth embodiment] Next, a method for joining metal members according to a fourth embodiment will be described with reference to Fig. 18 to Fig. 20. In particular, unlike the method for joining metal members according to the first embodiment, in the method for joining metal members according to the fourth embodiment, a backup portion is not formed in the segment coil 412. Note that in the fourth embodiment, the same reference numerals are used for configurations similar to those in the first embodiment, and descriptions thereof will be omitted.

[0083] As shown in FIG. 18, a motor 400 includes a stator 401 and a rotor (not shown).

[0084] The stator 401 is a busbar ring. Gu4 11 (An example of the "first metal member" and "bus bar" in the claims) And, segment carp Rule 4 12 (An example of the "second metal member," "second member," and "segment coil" in the claims.) It includes:

[0085] Busbar ring 411 has through hole 411a and groove 411b. Groove 411b is formed by recessing the inner surface of through hole 411a in a direction perpendicular to direction A (an example of the "insertion direction" in the claims).

[0086] The segment coil 412 is made of a different type of metal from the busbar ring 411. The segment coil 412 is formed in a rod shape. The segment coil 412 has a protruding portion 412a and a fitting portion 123. The protruding portion 412a protrudes in a direction perpendicular to the A direction in a cross section perpendicular to the A direction. The protruding portion 412a may be provided on the entire outer circumferential surface of the segment coil 412, or may be provided on a part of the outer circumferential surface of the segment coil 412. The segment coil 412 is positioned in the A direction by the engagement between the groove portion 411b and the protruding portion 412a.

[0087] Moreover, the protrusion 412a has a modified form as shown in FIG. 19(A) and FIG. 19(B).

[0088] The protrusion 412a shown in Fig. 19(A) is formed in a substantially spiral shape on the outer peripheral surface of the segment coil 412. The protrusion 412a shown in Fig. 19(B) may be formed in a substantially tapered shape on the outer peripheral surface of the segment coil 412. Note that other configurations of the fourth embodiment are similar to those of the first embodiment, and therefore description thereof will be omitted.

[0089] (Method of joining metal components) Hereinafter, a method for joining metal members according to the fourth embodiment will be described with reference to Fig. 20. The method for joining metal members is a method for joining the bus bar ring 411 and the segment coil 412 together, which can prevent a load from being applied to the segment coil 412.

[0090] In step S401, a busbar ring 411 having a through hole 411a with a groove 411b is prepared (see FIG. 18). That is, in step S401, a through hole 411a with a groove 411b is formed in the busbar ring 411. Step S401 is a step of forming a groove 411b recessed in a direction perpendicular to the A direction in the through hole 411a. Note that step S401 is an example of a "first metal member preparation step" in the claims. Here, the contents of steps S2 and S3 are the same as those of steps S2 and S3 in the first embodiment, and therefore description thereof will be omitted.

[0091] In step S404, a laser L (an example of the "high density energy beam" in the claims) is irradiated to the tip portion (shaft portion) of the segment coil 412. Here, step S404 is a step of melting the segment coil 412 and pouring a part of the molten segment coil 312 into the groove portion 411b in the through hole 411a. Note that step S404 is an example of the "joining step" in the claims.

[0092] (Effects of the fourth embodiment) In the fourth embodiment, the following effects can be obtained.

[0093] In the fourth embodiment, as in the first embodiment, the method for joining metal members includes step S4 of melting the segment coil 412 to join the busbar ring 411 and the segment coil 412 without pressing the segment coil 412 with the tip portion (shaft portion) of the segment coil 412 inserted into the through hole 411a of the busbar ring 411. This makes it possible to prevent the device for joining metal members from becoming larger and more complicated. Note that other effects of the fourth embodiment are similar to those of the first embodiment, and therefore description thereof will be omitted.

[0094] [Fifth embodiment] Next, a method for joining metal members according to a fifth embodiment will be described with reference to Fig. 21 to Fig. 25. In particular, unlike the method for joining metal members according to the first embodiment, in the method for joining metal members according to the fifth embodiment, a laser L is irradiated so as to join a part of the shaft portion 512a of the segment coil 512 and a part of the bus bar ring 11. Note that in the fifth embodiment, the same reference numerals are used for configurations similar to those in the first embodiment, and descriptions thereof will be omitted.

[0095] As shown in FIGS. 21 and 22, the motor 500 includes a stator 501 and a rotor (not shown).

[0096] The stator 501 is a busbar ring. Gu 1 1 (An example of the "first metal member" and "bus bar" in the claims) And, segment carp Ru5 12 (An example of the "second metal member," "second member," and "segment coil" in the claims.) and weld 513.

[0097] The segment coil 512 has a shaft portion 512a. The shaft portion 512a has a melt-solidified portion 5121, a backup portion 122, and a fitting portion 123. The melt-solidified portion 5121 is formed by melting and solidifying the tip portion of the shaft portion 512a.

[0098] The molten solidified portion 5121 is formed by melting and solidifying the tip of the shaft portion 512a. The segment coil 512 is engaged with the busbar ring 11 via the molten solidified portion 5121. The molten solidified portion 5121 has a tapered shape that expands in a direction perpendicular to the A direction toward the tip of the segment coil 512 in the A direction. In addition, the molten solidified portion 5121 has a portion that protrudes in the A direction from the tip of the through hole 11a in the A direction. The backup portion 122 is an end surface on the shaft portion 512a side of the other portion 12b other than the shaft portion 512a of the segment coil 512. The backup portion 122 is an abutting surface that abuts against the busbar ring 11. The fitting portion 123 is a portion between the molten solidified portion 5121 and the fitting portion 123 of the segment coil 512. The fitting portion 123 is a portion that fits into the through hole 11a. The fitting portion 123 is fitted into the through hole 11a with a clearance fit.

[0099] The welded portion 513 is formed by solidifying (welding) a part of the busbar ring 11 and a part of the segment coil 512 melted by a laser L (an example of a "high density energy beam" in the claims) in a mixed state. That is, the welded portion 513 joins the busbar ring 11 and the segment coil 512 by welding them partially, not entirely. As a result, the busbar ring 11 and the segment coil 512 are partially joined via the welded portion 513, so that the rotation of the segment coil 512 is restricted. In this way, the welded portion 513 is a rotation stopper portion that restricts the rotation of the segment coil 512. The other configurations of the fifth embodiment are similar to those of the first embodiment, so that a description thereof will be omitted.

[0100] (Method of joining metal components) Hereinafter, a method for joining metal members will be described with reference to Fig. 23 to Fig. 25. The method for joining metal members is a joining method that can prevent a load from being applied to the segment coil 512 when joining the bus bar ring 11 and the segment coil 512.

[0101] The contents of steps S1 to S3 are the same as those of steps S1 to S3 of the joining method of metal members of the first embodiment, so that the description will be omitted. In step S504, the laser L is intermittently irradiated so as to cross the shaft portion 512a of the segment coil 512 in a plan view. That is, in step S504, the laser L is irradiated to melt both the bus bar ring 11 and the segment coil 512 to partially weld and join the bus bar ring 11 and the segment coil 512, and either the segment coil 512 or the bus bar ring 11 is melted to join the segment coil 512 and the bus bar ring 11 by welding. In this way, in step S504, the bus bar ring 11 and the segment coil 512 are joined by welding partially, not entirely. Note that step S504 is an example of a "joining step" in the claims. After step S504, the joining method of metal members ends.

[0102] (Effects of the fifth embodiment) In the fifth embodiment, the following effects can be obtained.

[0103] In the fifth embodiment, similarly to the first embodiment, the method for joining metal members includes step S504 of melting the segment coil 512 to join the busbar ring 11 and the segment coil 512 without pressing the segment coil 512 in a state where the shaft portion 512a of the segment coil 512 is inserted into the through hole 11a of the busbar ring 11. This makes it possible to prevent the device for joining metal members from becoming larger and more complicated.

[0104] Also, in the fifth embodiment, as described above, step S504 is a step of irradiating the laser L to melt both the segment coil 512 and the busbar ring 11 to partially join the segment coil 512 and the busbar ring 11 by welding, and melting the segment coil 512 to join the segment coil 512 and the busbar ring 11. As a result, the portion (welded portion 513) where the segment coil 512 and the busbar ring 11 are partially welded can restrict rotation within the through hole 11a of the shaft portion 512a, so that the segment coil 512 and the busbar ring 11 can be joined so as to prevent movement in the rotation direction of the shaft portion 12a.

[0105] In the fifth embodiment, as described above, the metal member joining structure includes a metal busbar ring 11 having a through hole 11a formed therein, and a segment coil 512 including a shaft portion 512a inserted into the through hole 11a of the busbar ring 11 and provided separately from the busbar ring 11. The shaft portion 512a has a molten solidified portion 5121 in which a tip portion is melted and solidified. The segment coil 512 is engaged with the busbar ring 11 via the molten solidified portion 5121. When viewed from the A direction, the molten solidified portion 5121 and the edge portion of the through hole 11a in the busbar ring 11 are joined via a welded portion 513 that is partially welded. This makes it possible to restrict the rotation of the shaft portion 512a in the through hole 11a, and therefore it is possible to obtain a metal member joining structure that can join the busbar ring 11 and the segment coil 512 so as to prevent the busbar ring 11 from moving in the rotation direction of the shaft portion 512a. Note that other effects of the fifth embodiment are similar to those of the first embodiment, and therefore will not be described.

[0106] [Sixth embodiment] Next, a method for joining metal members according to a sixth embodiment will be described with reference to Fig. 26 to Fig. 28. In particular, unlike the method for joining metal members according to the first embodiment, the method for joining metal members according to the sixth embodiment irradiates a laser L onto an elongated portion 6121 of an axis portion 12a of a segment coil 612. Note that in the sixth embodiment, the same components as those in the first embodiment are denoted by the same reference numerals and description thereof will be omitted.

[0107] (Method of joining metal components) Hereinafter, a method for joining metal members according to the sixth embodiment will be described with reference to Figs. 26 to 28. Gu 1 1 (An example of the "first metal member" and "bus bar" in the claims) And, segment carp Ru6 12 (An example of the "second metal member," "second member," and "segment coil" in the claims.) This is a joining method that makes it possible to avoid placing a load on the segment coil 12 when joining the above.

[0108] The contents of step S1 and step S3 are the same as those of step S1 and step S3 of the joining method of metal members of the first embodiment, and therefore the description will be omitted. In step S602, a segment coil 612 having an axial portion 12a with an elongated portion 6121 is prepared (see FIG. 27). That is, in step S602, the axial portion 12a and the elongated portion 6121 are formed in the segment coil 612. Step S602 is a step of forming the elongated portion 6121 by thinning the portion of the axial portion 12a on the tip side from the portion to be fitted into the through hole 11a. Note that step S602 is an example of a "second metal member preparation step" in the claims.

[0109] In step S604, the elongated portion 6121 of the shaft portion 12a of the segment coil 612 is irradiated with a laser L (see FIG. 28). That is, in step S604, the elongated portion 6121 of the segment coil 12 is melted by irradiating the laser L, and the molten elongated portion 6121 flows into the space where the tapered portion 111 of the through hole 11a is provided. Then, the molten shaft portion 12a in the space where the tapered portion 111 is provided is cooled by the outside air and solidifies. After step S604, the joining method of metal members is completed. Note that step S604 is an example of a "joining step" in the claims.

[0110] (Effects of the sixth embodiment) In the sixth embodiment, the following effects can be obtained.

[0111] In the sixth embodiment, as in the first embodiment, the method for joining metal members includes step S604 of melting the segment coil 612 to join the busbar ring 11 and the segment coil 612 without pressing the segment coil 612 in a state where the shaft portion 12a of the segment coil 612 is inserted into the through hole 11a of the busbar ring 11. This makes it possible to prevent the device for joining metal members from becoming larger and more complicated. Note that other effects of the sixth embodiment are similar to those of the first embodiment, and therefore description thereof will be omitted.

[0112] [Seventh embodiment] Next, a method for joining metal members according to a seventh embodiment will be described with reference to Fig. 29 to Fig. 31. In particular, unlike the method for joining metal members according to the first embodiment, in the method for joining metal members according to the seventh embodiment, a laser L is irradiated onto a recess 7121 of an axis portion 712a of a segment coil 712. Note that in the seventh embodiment, the same reference numerals are used for configurations similar to those in the first embodiment, and description thereof will be omitted.

[0113] (Method of joining metal components) Hereinafter, a method for joining metal members according to the seventh embodiment will be described with reference to Figs. 29 to 31. (An example of the "first metal member" and "bus bar" in the claims) and segment coil 712 (An example of the "second metal member," "second member," and "segment coil" in the claims.) This is a joining method that can prevent a load from being applied to the segment coil 712 when joining the two.

[0114] The contents of step S1 and step S3 are the same as those of step S1 and step S3 of the joining method of metal members of the first embodiment, and therefore the description will be omitted. In step S702, a segment coil 712 having an axis portion 712a with a recess 7121 is prepared (see FIG. 30). That is, in step S702, the axis portion 712a and the recess 7121 are formed in the segment coil 712 (see FIG. 30). That is, step S702 is a step of forming the recess 7121 by recessing the axis portion 712a of the segment coil 712 in the direction opposite to the A direction (an example of the "insertion direction" in the claims). Note that step S702 is an example of the "second metal member preparation step" in the claims.

[0115] In step S704, the recess 7121 of the shaft portion 712a of the segment coil 612 is irradiated with a laser L (see FIG. 31). That is, step S704 is a step of joining the segment coil 712 and the busbar ring 11 by irradiating the recess 7121 with the laser L as a high-density energy beam. As a result, by irradiating the laser L, the portion around the recess 7121 of the segment coil 712 melts, and the molten shaft portion 712a flows into the space in which the tapered portion 111 of the through hole 11a is provided. Then, the molten shaft portion 712a in the space in which the tapered portion 111 is provided is cooled by the outside air and solidified. After step S704, the joining method of the metal members is completed. Note that step S702 is an example of a "joining step" in the claims.

[0116] (Effects of the Seventh Embodiment) In the seventh embodiment, the following effects can be obtained.

[0117] In the seventh embodiment, as in the first embodiment, the method for joining metal members includes step S704 of melting the segment coil 712 to join the busbar ring 11 and the segment coil 712 without pressing the segment coil 712 in a state where the shaft portion 712a of the segment coil 712 is inserted into the through hole 11a of the busbar ring 11. This makes it possible to prevent the device for joining metal members from becoming larger and more complicated. Note that other effects of the seventh embodiment are similar to those of the first embodiment, and therefore description thereof will be omitted.

[0118] [Variations] The above-described embodiments disclosed herein should be considered as illustrative and not restrictive in all respects. The scope of the present invention is indicated by the claims, not by the description of the above-described embodiments, and further includes all modifications (variations) within the meaning and scope of the claims.

[0119] For example, in the first to seventh embodiments, the busbar rings 11 (211, 311, 411: first member) are formed of aluminum, but the present invention is not limited thereto. In the present invention, the first member may be formed of a metal other than aluminum, a resin, or the like. Here, when the first member is made of resin, the method for joining members includes a first member preparation step of preparing a first member made of resin and having a through hole. The method for joining members includes a second member preparation step of preparing a second member made of metal and separate from the first member, the second member having an axial portion that can be inserted into the through hole of the first member. The method for joining members includes an insertion step of inserting the axial portion of the second member into the through hole of the first member. The method for joining members includes a joining step of melting the second member without pressing the second member in a state in which the axial portion of the second member is inserted into the through hole of the first member, to join the first member and the second member. This makes it difficult for external forces to be applied to the second member, so that even if the second member is made of a material with low rigidity, there is no need to melt the second member while it is clamped and fixed in position. As a result, a method for joining members can be obtained that can prevent the device for joining members from becoming larger and more complicated by not requiring a dedicated clamp device for clamping and fixing the second member in position.

[0120] In the above first to seventh embodiments, the segment coils 12 (212, 412, 512, 612, 712, 812: second metal member) are formed of copper as a metal different from that of the busbar rings 11 (211, 311, 411: first metal member), but the present invention is not limited to this. In the present invention, the second metal member may be formed of a metal (for example, copper) of the same material as the first metal member.

[0121] In the first to seventh embodiments, the busbar ring 11 (211, 311, 411: first metal member) and the segment coil 12 (212, 412, 512, 612, 712, 812: second metal member) are joined together, but the present invention is not limited to this. In the present invention, a flat wire coil as the first metal member and a flat wire coil as the second metal member may be joined together.

[0122] In the first to seventh embodiments, an example is shown in which the laser L is irradiated onto the shaft portion 12a (212a, 412a, 512a, 712a) of the segment coil 12 (212, 412, 512, 612, 712, 812: second metal member), but the present invention is not limited to this. In the present invention, the shaft portion of the second metal member may be melted by contacting a high-temperature heat source such as a heater with the shaft portion of the second metal member. This allows the high-temperature heat source to melt the segment coil by only slightly contacting the segment coil, thereby reducing the load on the segment coil when melting the segment coil.

[0123] In the first to seventh embodiments, the laser L (high-density energy beam) is a green laser, but the present invention is not limited to this. In the present invention, the high-density energy beam may be an electron beam.

[0124] In the first to seventh embodiments, an example has been shown in which the shaft portion 12a (212a, 412a, 512a, 712a) of the segment coil 12 (212, 412, 512, 612, 712, 812: second metal member) and the through hole 11a (211a, 311a, 811a) of the busbar ring 11 (211, 311, 411: first metal member) are arranged coaxially in the A direction (insertion direction), but the present invention is not limited to this. In the present invention, the shaft portion of the second metal member and the through hole of the busbar ring do not have to be arranged coaxially in the insertion direction (they may be eccentric).

[0125] In the above first to seventh embodiments, the method for joining metal members includes step S2 (S202, S602, S702) of forming a shaft portion by making the tip portion of the rod-shaped segment coil 12 (212, 412, 512, 612, 712, 812: second metal member) thinner than the other portions, but the present invention is not limited to this. In the present invention, the method for joining metal members does not have to include the step of forming a shaft portion by making the tip portion of the rod-shaped second metal member thinner than the other portions.

[0126] In the first to seventh embodiments, an example of joining the through hole 11a (211a, 311a, 811a) of the busbar ring 11 (211, 311, 411: first metal member) and the rod-shaped segment coil 12 (212, 412, 512, 612, 712, 812: second metal member) is shown, but the present invention is not limited thereto. In the present invention, the first metal member and the second metal member may have a joining structure having a cross-sectional shape like the modified example shown in FIG. 32(A) to FIG. 32(F) as an example of joining. The through hole 811a shown in FIG. 32(A) has a circular arc-shaped portion 811. The through hole 811a shown in FIG. 32(B) has a step portion 811. The through hole 811a shown in FIG. 32(C) does not have a specific shape. The through hole 811a shown in FIG. 32(D) has a step portion 811 having an inclined surface. 32(E) has a step portion 811 having a recess. It has an arc-shaped portion 811. The through hole 811a shown in FIG.

[0127] In addition, in the above first to seventh embodiments, the method for joining metal members is applied to the motor 100 (200, 300, 400, 500, 600, 700, 800) by way of example, but the present invention is not limited thereto. In the present invention, the method for joining metal members may be applied to devices other than motors. [Explanation of symbols]

[0128] 1 Stator 11, 211, 311, 411 Busbar ring (first metal member, busbar) 11a, 211a, 311a, 411a, 811a through hole 12, 212, 312, 412, 512, 612, 712 Segment coil (second metal member, second member, coil) 12a, 212a, 312a, 512a, 712a Shaft 12b Other parts 13 Slots 121, 2121 Engagement part 513 Welding 3111 Anti-rotation part 5121 Melted and solidified part L Laser

Claims

1. A first metal member preparation step of preparing a first metal member made of metal and having a through hole; a second metal member preparation step of preparing a second metal member separate from the first metal member, the second metal member having a shaft portion that can be inserted into the through hole of the first metal member; an inserting step of inserting the shaft portion of the second metal member into the through hole of the first metal member; a joining step of melting either the first metal member or the second metal member without pressing the second metal member with the shaft portion of the second metal member inserted into the through hole of the first metal member, and joining the first metal member and the second metal member using an engaging portion formed by flowing the molten either the first metal member or the second metal member into a groove portion or a tapered portion between an inner surface of the through hole and the shaft portion and melting and solidifying the first metal member and the second metal member.

2. 2. The method for joining metal members according to claim 1, wherein the joining step includes a step of melting and joining either the first metal member or the second metal member by a high-density energy beam or a high-temperature heat source without pressing the second metal member.

3. 3. The method for joining metal members according to claim 1 or 2, wherein the second metal member preparation step includes a step of preparing the second metal member having a shaft portion in which the tip portion of the rod-shaped second metal member is thinner than other portions.

4. The method for joining metal members according to any one of claims 1 to 3, further comprising a step of forming a non-circular anti-rotation portion in at least one of the through hole or the shaft portion to stop rotation of the shaft portion relative to the through hole.

5. The method for joining metal members according to any one of claims 1 to 3, wherein the joining step includes a step of melting both the first metal member and the second metal member by irradiating a high-density energy beam to partially join the first metal member and the second metal member by welding, and melting either the first metal member or the second metal member to join the first metal member and the second metal member.

6. The joining step is performed by melting either the first metal member or the second metal member with a laser as the high-density energy beam without pressing the second metal member. The method for joining metal members according to claim 2 , further comprising the step of: bonding the metal members together by placing the metal members in a position where the metal members are joined together.

7. the second metal member is a coil inserted into a slot provided in a stator, the shaft portion is a coil end of the coil protruding outside the slot of the stator in the axial direction, The method for joining metal members according to any one of claims 1 to 6, wherein the joining step includes a step of melting and joining either the coil of the stator or the busbar of the stator without pressing the coil of the stator, with the shaft portion of the coil of the stator as the second metal member inserted into the through hole of the busbar of the stator as the first metal member.

8. A first metal member made of metal and having a through hole formed therein; a second metal member including a shaft portion inserted into the through hole of the first metal member and provided separately from the first metal member; the shaft portion has an engagement portion formed by melting and solidifying a tip portion at a tapered portion between the shaft portion and an inner surface of the through hole of the first metal member, the second metal member is engaged with the first metal member by using the engaging portion, A metal member joining structure, wherein, when viewed from the insertion direction of the shaft portion, the first metal member and the second metal member are joined via a partially welded welded portion.

Images