JP7364310B2 - Method for connecting rectangular conductive wire and method for manufacturing stator of rotating electric machine - Google Patents

Description

The present disclosure relates to a method for connecting rectangular conductive wires and a method for manufacturing a stator for a rotating electric machine.

For example, in a rotating electrical machine such as an electric motor or a generator, a stator is configured by, for example, a stator winding attached to a stator core. In addition, for example, in rotating electric machines, square wires with a rectangular cross section (square conductor wire) are used instead of round wires with a circular cross section as winding wires in order to improve the space factor of the windings due to the demand for miniaturization and improved efficiency. It is now possible to
Further, for example, in a rotating electrical machine, a device in which a plurality of segment conductors made of rectangular wires are connected and used as a stator winding is known (see, for example, Patent Document 1).

Japanese Patent Application Publication No. 2014-7794

For example, in Patent Document 1, as a method for joining conductors in a rotating electric machine, a plate-shaped conductive plate is installed on the tip end surface of each of two segment conductors to be joined, and a laser is irradiated to connect the two segment conductors. Disclosed is the welding of each tip to a conductive plate.
In the conductor joining method described in Patent Document 1, the current flowing between the two segment conductors mainly flows through the conductive plate. However, if the contact between the tip surface of the segment conductor and the surface of the conductive plate opposite to the tip surface is not good, the current flowing between the segment conductor and the conductive plate will mainly flow between the tip of the segment conductor and the conductive plate. It flows through the portion where the plate is joined in a skewering manner, that is, through the melted region that is formed to elongate in the direction in which the segment conductor extends during laser irradiation. The cross-sectional area of the joined portion is smaller than the area of the tip surface of the segment conductor. Therefore, it may become difficult to flow a sufficiently large current between the two segment conductors.

In view of the above-mentioned circumstances, at least one embodiment of the present disclosure aims to provide a method for connecting rectangular conductive wires that allows a sufficient current to flow at the connection portion between the conductive wires.

(1) A method for connecting a rectangular conductive wire according to at least one embodiment of the present disclosure includes:
With the first end surface of the first conductive wire having a rectangular cross section and the second end surface of the second conductive wire having a rectangular cross section being adjacent to each other, the first end surface and arranging a cover member to cover at least a portion of the second end surface;
An energy beam is irradiated to the covering member disposed across the first end surface and the second end surface, melting the entire covering member, and melting the covering member, the end of the first conductive wire, and the first conductive wire. generating a molten layer in which the ends of the two conductive wires are fused;
Equipped with

According to the method (1) above, the entire covering member is melted to generate a molten layer in which the covering member, the end of the first conducting wire, and the end of the second conducting wire are melted, so that the first conducting wire and the end of the second conducting wire are melted. The size of the connection part where the two conductors are connected by welding can be secured. This allows sufficient current to flow through the connection. Therefore, the reliability of the connection between the first conductive wire and the second conductive wire can be improved.
Further, according to the method (1) above, since at least a portion of the first end surface and the second end surface is covered with the covering member across the first end surface and the second end surface, for example, the end of the first conductive wire and the second end surface are covered with the covering member. Even if a gap exists between the conductor and the end of the conductor, it is possible to prevent the irradiated energy beam from passing through the gap and resulting in insufficient generation of the molten layer.
Further, according to the method (1) above, it is possible to prevent the irradiated energy beam from passing through the gap as described above, so there is no need to increase the output of the energy beam unnecessarily, and the energy beam It is possible to suppress the performance required of the irradiation device for outputting from becoming excessive.

(2) In some embodiments, in the method of (1) above, the step of arranging the cover member includes an end facing portion formed to face the first end surface and the second end surface; The cover member has a side facing portion formed to face at least a portion of the side surface of the first conducting wire and the second conducting wire, and the covering member has a side facing portion formed to face at least a portion of the side surface of the first conducting wire and the second conducting wire. placed so as to cover at least a portion of the

According to the method (2) above, the side facing portion and at least part of the side surfaces of the first conductive wire and the second conductive wire come into contact with each other, thereby preventing misalignment between the first conductive wire or the second conductive wire and the cover member. It can be prevented.

(3) In some embodiments, in the method (1) or (2) above, the step of arranging the cover member includes the first end surface and the extension of the second conductive wire with respect to the first end surface. The cover member is disposed so as to straddle the second end surface that is disposed at a position protruding in the direction in which the cover member is disposed.

According to the method (3) above, even if the positions of the first end surface and the second end surface are shifted in the extending direction of the first conductor or the second conductor, the arrangement can be made astride the first end surface and the second end surface. By irradiating the covered member with an energy beam, the above-mentioned molten layer can be generated.

(4) In some embodiments, in any of the methods (1) to (3) above, the step of generating the molten layer includes irradiating the entire covering member with the energy beam while scanning. is melted to generate a molten layer in which the covering member, the end of the first conductive wire, and the end of the second conductive wire are melted.

According to the method (4) above, the above-mentioned molten layer can be efficiently generated.

(5) In some embodiments, in any of the methods (1) to (3) above, the step of generating the molten layer includes forming an edge of the first end surface and the second end surface of the covering member. The energy beam is irradiated to a portion covering a region where the edges of the end face are adjacent to each other, melting the entire covering member, and melting the covering member, the end of the first conductive wire, and the second conductive wire. A molten layer is generated in which the ends are fused.

According to the method (5) above, it is possible to suppress the shape of the molten layer described above from being different between the first conducting wire side and the second conducting wire side.

(6) In some embodiments, in any of the methods (1) to (5) above, the step of arranging the cover member includes straddling the first end face and the second end face facing upward, respectively. A covering member is arranged to cover at least a portion of the first end face and the second end face.

According to the method (6) above, there is less need to temporarily fasten the placed cover member to the first conductive wire and the second conductive wire, and the effort and cost required for temporary fastening can be suppressed.

(7) In some embodiments, in any of the methods (1) to (6) above, the step of arranging the cover member is formed so as to face the first end surface and the second end surface. The covering member having a plate thickness of 0.1 mm or more and 0.5 mm or less at the end facing portion thereof is disposed astride the first end surface and the second end surface.

As a result of intensive study by the inventors, as long as the plate thickness of the end facing portion is 0.1 mm or more, even if there is a gap between the end of the first conductor and the end of the second conductor, It has been found that it is possible to prevent the irradiated energy beam from penetrating the cover member and passing through the gap. In addition, as a result of intensive study by the inventors, it was found that the time required to generate the above-mentioned molten layer does not change much depending on the presence or absence of the cover member, as long as the plate thickness of the end facing portion is 0.5 mm or less. Ta.
According to the method (7) above, the above-mentioned molten layer can be efficiently generated.

(8) In some embodiments, in any of the methods (1) to (7) above, the step of arranging the covering member includes the step of arranging the covering member, which is made of the same material as the first conducting wire and the second conducting wire. A cover member is disposed across the first end surface and the second end surface.

According to the method (8) above, since the composition of the above-mentioned molten layer becomes the same as that of the first conductive wire and the second conductive wire, the influence on the electrical characteristics can be suppressed.

(9) In some embodiments, in any of the methods (1) to (7) above, the step of arranging the cover member includes the cover member having a material different from that of the first conductive wire and the second conductive wire. A member is disposed across the first end surface and the second end surface.

According to the method (9) above, the above-mentioned molten layer can be efficiently generated if the covering member is made of a material whose energy beam absorption rate is higher than that of the first conductive wire and the second conductive wire, for example.

(10) In some embodiments, in any of the methods (1) to (9) above, the step of arranging the covering member includes the step of arranging the covering member in the rectangular cross section whose length on one side is 1 mm or more and 5 mm or less. The cover member may be disposed astride the first end surface of the first conductive wire and the second end surface of the second conductive wire, the length of one side of which is rectangular in cross section, being 1 mm or more and 5 mm or less.

(11) In some embodiments, in any of the methods (1) to (10) above,
Inserting the first conductive wire from one end of one of the plurality of slots toward the other end in a stator core of a rotating electric machine, and protruding the first end surface from the other end to the outside of the one slot. the step of
Inserting the second conductive wire from one end to the other end of another slot different from the one slot to cause the second end surface to protrude from the other end to the outside of the other slot;
arranging the first end surface and the second end surface protruding to the outside of the slot adjacent to each other;
Furthermore,
The step of arranging the cover members is performed after the step of arranging them next to each other is performed.

According to the method (11) above, the windings of the stator of the rotating electric machine can be efficiently connected.

(12) A method for manufacturing a stator for a rotating electrical machine according to at least one embodiment of the present disclosure,
A first conductive wire having a rectangular cross section is inserted from one end of one slot of a plurality of slots in a stator core of a rotating electric machine toward the other end, and the first end surface of the first conductive wire is passed from the other end to the a step of protruding to the outside of the first slot;
A second conductive wire having a rectangular cross section is inserted from one end of another slot different from the first slot toward the other end, and a second end surface of the second conductor is extended from the other end to the outside of the other slot. A step to make it stand out;
arranging the first end surface and the second end surface protruding to the outside of the slot adjacent to each other;
arranging a cover member so as to cover at least a portion of the first end surface and the second end surface, spanning the first end surface and the second end surface that are arranged next to each other;
An energy beam is irradiated to the covering member disposed across the first end surface and the second end surface, melting the entire covering member, and melting the covering member, the end of the first conductive wire, and the first conductive wire. generating a molten layer in which the ends of the two conductive wires are fused;
Equipped with

According to the method (12) above, a stator for a rotating electrical machine can be efficiently manufactured.

According to at least one embodiment of the present disclosure, it is possible to provide a method for connecting rectangular conductive wires that allows a sufficient current to flow in the connection portion between the conductive wires.

1 is a diagram schematically showing the configuration of a rotating electrical machine according to some embodiments. FIG. 2 is a perspective view of a housing and stator according to some embodiments. FIG. 3 is a schematic perspective view of segment conductors that constitute a stator winding. FIG. 3 is a schematic diagram for explaining a procedure for forming stator windings according to some embodiments. FIG. 3 is a schematic diagram showing the vicinity of the end portions in a state where the end surfaces are arranged next to each other. FIG. 3 is a schematic diagram showing a state in which a cover member is placed across two end faces that are placed next to each other. FIG. 3 is a schematic view from above of a cover member disposed straddling two end faces disposed next to each other. FIG. 3 is a schematic perspective view of an example of a cover member according to some embodiments. FIG. 6 is a schematic diagram showing a state immediately after laser beam irradiation is started after a covering member is placed on the end face of a segment conductor. FIG. 3 is a schematic diagram showing a state immediately after starting laser beam irradiation. FIG. 3 is a diagram schematically showing the state of formation of a molten layer. It is a figure which shows an example of other embodiment regarding irradiation of a laser beam. FIG. 7 is a schematic diagram illustrating how cover members are placed on end faces that are placed next to each other. FIG. 7 is a schematic diagram showing a state after a covering member is disposed on the end face when the positions of the first end face and the second end face are shifted in the extending direction of the first conductive wire and the second conductive wire. 3 is a flowchart illustrating processing steps in a method for manufacturing a stator of a rotating electric machine according to some embodiments.

Hereinafter, some embodiments of the present invention will be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the components described as the embodiments or shown in the drawings are not intended to limit the scope of the present invention thereto, and are merely illustrative examples. do not have.
For example, expressions expressing relative or absolute positioning such as "in a certain direction,""along a certain direction,""parallel,""orthogonal,""centered,""concentric," or "coaxial" are strictly In addition to representing such an arrangement, it also represents a state in which they are relatively displaced with a tolerance or an angle or distance that allows the same function to be obtained.
For example, expressions such as "same,""equal," and "homogeneous" that indicate that things are in an equal state do not only mean that things are exactly equal, but also have tolerances or differences in the degree to which the same function can be obtained. It also represents the existing state.
For example, expressions expressing shapes such as squares and cylinders do not only refer to shapes such as squares and cylinders in a strict geometric sense, but also include uneven parts and chamfers to the extent that the same effect can be obtained. Shapes including parts, etc. shall also be expressed.
On the other hand, the expressions "comprising,""comprising,""comprising,""containing," or "having" one component are not exclusive expressions that exclude the presence of other components.

(Summary of configuration of rotating electrical machine 1)
FIG. 1 is a diagram schematically showing the configuration of a rotating electrical machine according to some embodiments. FIG. 1 illustrates a cross section of a portion of a rotating electrical machine according to some embodiments. The rotating electrical machine 1 shown in FIG. 1 may be used as an electric motor or as a generator.
The rotating electric machine 1 according to some embodiments includes a housing 3 and a stator 10 fixed inside the housing 3. The stator 10 includes a stator core 11 and a stator winding 13. A rotor 5 is rotatably held inside the stator core 11 via a gap. The rotor 5 is fixed to a cylindrical shaft 7. The housing 3, stator 10, and rotor 5 are arranged inside a case 9. Case 9 rotatably supports shaft 7.
In the following description, the direction in which the axis AX of the shaft 7 extends is also simply referred to as the axial direction, the circumferential direction around the axis AX is also simply referred to as the circumferential direction, and the radial direction around the axis AX is also simply referred to as the radial direction. .

FIG. 2 is a perspective view of the housing 3 and stator 10 according to some embodiments. Note that the stator 10 shown in FIG. 2 is in a state before end portions 25 of segment conductors 20, which will be described later, are connected to each other by welding.
FIG. 3 is a schematic perspective view of the segment conductor 20 constituting the stator winding 13, showing a state before being attached to the stator core 11.

In the stator 10 according to some embodiments, in order to improve the space factor of the winding due to the demand for downsizing and improving efficiency of the rotating electric machine 1, the stator winding 13 is made of square wire (square conductor wire) having a rectangular cross section. )2 is used. In some embodiments, the rectangular conductive wire 2 is formed into a segment conductor 20 having a U-shape as shown in FIG. That is, in some embodiments, the segment conductor 20 has a U-shaped portion 21 bent into a U-shape, and two linear portions 23 extending linearly from the U-shaped portion 21.
Although not shown in FIG. 3, the surface of the rectangular conductive wire 2 used in the segment conductor 20 according to some embodiments is coated with an insulating coating 29 (see FIG. 5) such as enamel. It's okay.
In the stator 10 according to some embodiments, the stator windings are connected by welding the ends 25 of the plurality of segment conductors 20 inserted through the plurality of slots 15 of the stator core 11. 13 is formed.

(Outline of procedure for forming stator winding 13)
FIG. 4 is a schematic diagram for explaining a procedure for forming the stator winding 13 according to some embodiments. In addition, in FIG. 4, the stator 10 is seen from the inside in the radial direction and shows a state in which it is expanded along the circumferential direction.
For convenience of explanation, FIG. 4 will be described with reference to two segment conductors 20 out of a large number of segment conductors 20, in which end portions 25 of straight portions 23 are connected by welding as described later. In the following description, when it is necessary to distinguish between the two segment conductors 20, one segment conductor 20 will be referred to as the first segment conductor 20A, and the other segment conductor 20 will be referred to as the second segment conductor 20B. . Further, the rectangular conductive wire 2 constituting the first segment conductor 20A is also referred to as the first conductive wire 2A, and the rectangular conductive wire 2 constituting the second segment conductor 20B is also referred to as the second conductive wire 2B.

In some embodiments, stator winding 13 is formed as follows.
For example, in some embodiments, segment conductors 20 as shown in FIG. 3 are inserted into slots 15 of stator core 11 from the axial direction. At this time, the straight portion 23 of the segment conductor 20 is inserted into two slots 15 spaced apart from each other across the plurality of slots 15 . For example, in some embodiments, with the stator core 11 maintained in an attitude such that the axial direction of the stator core 11 is in the same direction as the vertical direction, the segment conductors 20 is inserted into the slot 15 from the bottom to the top.
In this way, the straight part 23 is inserted from one end of the slot 15 toward the other end, so that the end surface 27 on the tip side of the straight part 23 projects from the other end of the slot 15 to the outside of the slot 15.

Next, in order to electrically connect the ends 25 to each other by welding, one end 25 of the first segment conductor 20A and one end 25 of the second segment conductor 20B are brought close to each other, and the first segment The end surface 27 of one end 25 of the conductor 20A and the end surface 27 of one end 25 of the second segment conductor 20B are arranged adjacent to each other. Specifically, as shown by the arrow b in FIG. approach the end 25 of. Then, as shown by arrow c in FIG. 4, the respective ends 25 are bent so that the end surfaces 27 of the ends 25 that are close to each other face in the same direction, for example, upward. Thereby, the end surface 27 of one end 25 of the first segment conductor 20A and the end surface 27 of one end 25 of the second segment conductor 20B are arranged adjacent to each other.
FIG. 5 is a schematic diagram showing the vicinity of the end portion 25 in a state where the end surfaces 27 are arranged next to each other as described above. As shown in FIG. 5, in some embodiments, one end 25 of the first segment conductor 20A and one end 25 of the second segment conductor 20B are lined up along the radial direction. They may be lined up along the direction.
Note that it is desirable that the insulation coating 29 at the end portion 25 be removed in advance.
In the following description, the end surface 27 of the first segment conductor 20A (first conducting wire 2A) is also referred to as the first end surface 27A, and the end surface 27 of the second segment conductor 20B (second conducting wire 2B) is also referred to as the second end surface 27B.

Next, the adjacent end portions 25 are connected by welding. In some embodiments, prior to welding the end portions 25 together, the cover member 40 is placed across the two end surfaces 27 that are placed next to each other, as shown by the arrow d in FIGS. 4 and 5. . Then, by irradiating the cover member 40 disposed on the end surface 27 with an energy beam (for example, a laser beam), the end portions 25 together with the cover member 40 are melted and connected. Hereinafter, methods for connecting rectangular conductive wires according to some embodiments will be described in detail. Note that FIG. 6 is a schematic diagram showing a state in which the cover member 40 is placed across two end surfaces 27 that are placed next to each other. Moreover, FIG. 7 is a schematic diagram of the cover member 40 disposed straddling two end surfaces 27 disposed next to each other, viewed from above.

(About how to connect square conductor wire)
In some embodiments, the ends 25 of the segment conductors 20 are welded together using a laser beam as described above. However, as shown in FIG. 5, for example, even if the straight portion 23 whose end portion 25 projects outward from the slot 15 of the stator 10 is bent and the end surfaces 27 are arranged next to each other, one of the first conducting wires 2A A gap 17 may occur between the end 25 of the second conducting wire 2B and one end 25 of the second conducting wire 2B.

There are various reasons why this gap 17 occurs, and the following are some examples. For example, even if the straight portion 23 is bent as described above and the side surface 25a of one end 25 of the first conductive wire 2A and the side surface 25a of one end 25 of the second conductive wire 2B are brought into contact with each other, It is conceivable that the side surfaces 25a of the end portions 25 become separated due to springback of the rectangular conducting wire 2. In particular, as shown in FIG. 5, when the surface of the rectangular conducting wire 2 is coated with an insulating coating 29, the distance between the ends 25 is increased by the thickness of the insulating coating 29. , it is also considered that the gap 17 is more likely to occur.
Furthermore, if the segment conductor 20 moves relative to the stator core 11 due to the gap between the slot 15 and the straight portion 23, a gap 17 will be created.

When the ends 25 of the segment conductors 20 are connected by welding using an energy beam such as a laser beam, the molten layer generated by the laser beam and the connection formed by solidifying the molten layer are the two ends. It is desirable that the shape is not distorted, such as being biased toward either side of the portion 25. Therefore, it is desirable that the laser beam be applied to a region where the edge 27a of one end surface 27 and the edge 27a of the other end surface 27 are adjacent to each other.
However, if the gap 17 as described above exists, the irradiated laser beam may escape through the gap 17 and the end face 27 may not be sufficiently heated.

Therefore, in the method for connecting rectangular conductive wires according to some embodiments, prior to welding the end portions 25 together, as shown by arrow d in FIGS. 4 and 5, two end surfaces arranged next to each other are A cover member 40 is disposed across 27.
As a result, the covering member 40 covers the two end faces 27 arranged next to each other, so even if a gap 17 exists between the adjacent ends 25, the irradiated laser beam will escape through the gap 17. The cover member 40 suppresses this. Thereby, even if the gap 17 exists between the adjacent end portions 25, the end surfaces 27 can be sufficiently heated, so that the reliability of the connection between the adjacent end portions 25 by welding can be improved.

FIG. 8 is a schematic perspective view of an example of the cover member 40 according to some embodiments. In FIG. 8, the cover member 40 is depicted in such a position that the surface facing the end surface 27 of the segment conductor 20 is exposed. The cover member 40 according to some embodiments includes an end facing portion 41 formed to face a first end surface 27A and a second end surface 27B arranged next to each other, and a first conductive wire 2A and a second conductive wire 2B. and a side facing portion 43 formed to face at least a portion of the side surface 25a of the side surface 25a. That is, for example, the cover member 40 according to some embodiments is a cap-shaped member having the end facing portion 41 as a top plate. In the cover member 40 shown in FIG. 8, the side facing portions 43 are formed along the entire circumference of the end facing portions 41; There may be areas that are not specifically formed.

In some embodiments, the cover member 40 is arranged so that the end facing portion 41 covers at least a portion of the first end surface 27A and the second end surface 27B.
As a result, the side facing portions 43 come into contact with at least a portion of the side surfaces 25a of the first conductive wire 2A and the second conductive wire 2B, thereby preventing misalignment between the first conductive wire 2A or the second conductive wire 2B and the cover member 40. It can be prevented. Note that if the side facing portions 43 are provided at two locations separated with the end facing portion 41 in between, the movement of at least one of the first conducting wire 2A or the second conducting wire 2B is restricted by the two side facing portions 43. can. Further, as shown in FIG. 8, if the side facing portion 43 is provided over the entire circumference of the edge of the end facing portion 41, the first conductive wire 2A and the It is possible to prevent the two conductive wires 2B from being misaligned with each other.

FIG. 9 is a schematic diagram showing a state immediately after laser beam irradiation is started after the cover member 40 is placed on the end face 27 of the segment conductor 20, and is a view from above of the cover member 40. Similarly, FIG. 10 is a schematic diagram showing a state immediately after starting laser beam irradiation, and is a diagram of the cover member 40 and the segment conductor 20 viewed from the circumferential direction.
In some embodiments, for example, the laser beam 51 is applied to the cover member 40 disposed on the end surface 27 such that the edge 27a of the first end surface 27A and the edge 27a of the second end surface 27B are adjacent to each other. Irradiate the area. In other words, in some embodiments, when the first end surface 27A and the second end surface 27B arranged next to each other are viewed from above, the centroid of the projection plane including the first end surface 27A and the second end surface 27B A laser beam 51 is irradiated toward G.
In some embodiments, as shown in FIG. 11, the entire cover member 40 is melted to melt the cover member 40, the end 25 of the first conducting wire 2A, and the end 25 of the second conducting wire 2B. A molten layer 55 is generated. FIG. 11 is a diagram schematically showing how the molten layer 55 is formed. Note that the connection portion 57 is formed by solidifying the molten layer 55. The connecting portion 57 is a portion that electrically connects the end portion 25 of the first conducting wire 2A and the end portion 25 of the second conducting wire 2B.

According to some embodiments, the entire covering member 40 is melted to generate a molten layer 55 in which the covering member 40, the end portion 25 of the first conductive wire 2A, and the end portion 25 of the second conductive wire 2B are melted. , the size of the connecting portion 57 where the first conducting wire 2A and the second conducting wire 2B are connected by welding can be ensured. This allows sufficient current to flow through the connection portion 57. Therefore, the reliability of the connection between the first conducting wire 2A and the second conducting wire 2B can be improved. Here, the "sufficient current" is preferably a current equivalent to the allowable current that can be passed through the first conductive wire 2A and the second conductive wire 2B, for example.
Further, according to some embodiments, at least a portion of the first end surface 27A and the second end surface 27B is covered with the covering member 40 across the first end surface 27A and the second end surface 27B. Even if a gap 17 exists between the end 25 and the end 25 of the second conducting wire 2B, the irradiated laser beam passes through the gap 17, resulting in insufficient generation of the molten layer 55. You can prevent this from happening.
Further, according to some embodiments, since the existence of the gap 17 is allowed, high precision is no longer required for alignment between the first end surface 27A and the second end surface 27B, which is required for manufacturing the stator 10. Time and manufacturing costs can be reduced.
According to some embodiments, since the covering member 40 is disposed on the first end surface 27A and the second end surface 27B, the first conductive wire 2A and the first conducting wire 2A and the Since energy is used to melt the cover member 40 itself rather than heat transmitted to the end portion 25 of the second conducting wire 2B, the cover member 40 is preferentially melted. Thereafter, thermal energy is transmitted from the melted cover member 40 to the ends 25 of the first conductive wire 2A and the second conductive wire 2B, and the ends 25 of the first conductive wire 2A and the second conductive wire 2B can be efficiently melted.

FIG. 12 is a diagram showing an example of another embodiment regarding laser beam irradiation. In some embodiments, when the cover member 40 is irradiated with the laser beam 51, when the cover member 40 is viewed from above, that is, from the laser beam emission end side, within the region where the end opposing portion 41 exists. The laser beam 51 may be irradiated while scanning. In this case, for example, as shown in FIG. 12, scanning of the laser beam 51 is started from the centroid position of the first end face 27A or the centroid position of the second end face 27B when viewed from above, and The laser beam 51 may scan in a circular manner within the area where the laser beam 41 exists.

FIG. 13 is a schematic diagram showing how the cover members 40 are arranged on the end faces 27 arranged next to each other. Note that FIG. 13 shows a case where the positions of the first end surface 27A and the second end surface 27B are shifted in the extending direction of the first conductive wire 2A and the second conductive wire 2B. In the example shown in FIG. 13, the second end surface 27B is arranged at a position protruding from the first end surface 27A in the extending direction of the second conducting wire 2B.
FIG. 14 shows the arrangement of the cover member 40 on the end surface 27 when the positions of the first end surface 27A and the second end surface 27B are shifted in the extending direction of the first conductive wire 2A and the second conductive wire 2B as shown in FIG. FIG. 3 is a schematic diagram showing the state after the
As shown in FIG. 14, when the positions of the first end surface 27A and the second end surface 27B are shifted in the extending direction of the first conductive wire 2A and the second conductive wire 2B, when the cover member 40 is placed on the end surface 27, the cover member 40 is placed on the end surface 27. Although the member 40 is in a tilted state with respect to the end surface 27, the cover member 40 is prevented from slipping down by contacting the side surface 25a of the end portion 25. Therefore, as shown in FIG. 14, even if the positions of the first end surface 27A and the second end surface 27B are shifted in the extending direction of the first conductive wire 2A or the second conductive wire 2B, the first end surface 27A and the second end surface 27B The molten layer 55 can be generated by irradiating the laser beam onto the covering member 40 disposed across the two.

(About manufacturing method of stator of rotating electric machine)
A method for manufacturing a stator for a rotating electric machine using the above-described method for connecting rectangular conductive wires will be described.
FIG. 15 is a flowchart illustrating a processing procedure in a method for manufacturing a stator of a rotating electric machine according to some embodiments. A method of manufacturing a stator for a rotating electrical machine according to some embodiments includes an insertion step S1, a bending step S3, an arrangement step S5, and a welding step S7.
In the insertion step S1, the first conducting wire 2A having a rectangular cross section is inserted from one end of one slot 15 of the plurality of slots 15 in the stator core 11 of the rotating electrical machine 1 toward the other end. This includes the step of causing the first end surface 27A of the slot 15 to protrude from the other end to the outside of the slot 15. Further, in the insertion step S1, the second conductive wire 2B having a rectangular cross section is inserted from one end to the other end of another slot 15 different from the one slot 15, and the second end surface 27B of the second conductive wire 2B is inserted. This includes the step of protruding from the other end to the outside of the other slot 15.
In the insertion step S1, as described above, the segment conductor 20 as shown in FIG. 3 is inserted into the slot 15 of the stator core 11 from the axial direction.

The bending step S3 is a step of arranging the first end surface 27A and the second end surface 27B, which are protruded to the outside of the slot 15, adjacent to each other. In the bending step S3, as described above, one end 25 of the first segment conductor 20A and one end 25 of the second segment conductor 20B are brought close to each other, and the one end 25 of the first segment conductor 20A is and the end surface 27 of one end 25 of the second segment conductor 20B are arranged adjacent to each other.

The arrangement step S5 is a step of arranging the cover member 40 so as to cover at least a portion of the first end surface 27A and the second end surface 27B, spanning the first end surface 27A and the second end surface 27B that are arranged next to each other. In the placement step S5, as described above, the cover member 40 is placed across the two end surfaces 27 that are placed next to each other.

In the welding process S7, an energy beam such as a laser beam is irradiated to the cover member 40 disposed across the first end face 27A and the second end face 27B to melt the entire cover member 40 and separate the cover member 40 and the second end face 27B. This is a step of forming a connecting portion 57 by generating a molten layer 55 in which the end portion 25 of the first conducting wire 2A and the end portion 25 of the second conducting wire 2B are melted. In the welding step S7, as described above, the covering member 40 disposed on the end face 27 is irradiated with a laser beam to melt and connect the end portion 25 together with the covering member 40.
The method for manufacturing a stator for a rotating electric machine described above can efficiently manufacture the stator 10 for the rotating electric machine 1.

The connection method of the above-mentioned rectangular conducting wire can be summarized as follows.
A method for connecting a rectangular conducting wire according to some embodiments includes connecting the first end surface 27A and the second end surface 27B across the first end surface 27A and the second end surface 27B in a state where the first end surface 27A and the second end surface 27B are adjacent to each other. This includes an arrangement step S5 of arranging the cover member 40 so as to cover at least a portion of the second end surface 27B. In addition, the method for connecting rectangular conductive wires according to some embodiments includes irradiating an energy beam such as a laser beam onto the cover member 40 disposed across the first end surface 27A and the second end surface 27B. The process includes a welding step S7 in which the entirety of the wire 40 is melted to form a molten layer 55 in which the cover member 40, the end portion 25 of the first conducting wire 2A, and the end portion 25 of the second conducting wire 2B are melted.
In the method for connecting rectangular conductive wires according to some embodiments, the above-described molten layer 55 is generated, so that the size of the connecting portion 57 can be ensured. This allows sufficient current to flow through the connection portion 57. Therefore, the reliability of the connection between the first conducting wire 2A and the second conducting wire 2B can be improved.
Furthermore, in the method for connecting square conductive wires according to some embodiments, at least a portion of the first end surface 27A and the second end surface 27B is covered with the covering member 40 across the first end surface 27A and the second end surface 27B. For example, even if the gap 17 described above exists, it is possible to prevent the irradiated laser beam from passing through the gap 17 and resulting in insufficient generation of the molten layer 55.
Furthermore, according to the connection method of the rectangular conductive wire according to some embodiments, it is possible to prevent the irradiated laser beam from passing through the gap 17 as described above, so that the output of the laser beam is unnecessary. Therefore, it is possible to suppress the performance required of the irradiation device for outputting the laser beam from becoming excessive.

In the method for connecting rectangular conductive wires according to some embodiments, in the arrangement step S5, as shown in FIGS. The cover member 40 can also be placed astride the second end surface 27B, which is placed at a position protruding in the direction.
Therefore, as shown in FIG. 14, even if the positions of the first end surface 27A and the second end surface 27B are shifted in the extending direction of the first conductive wire 2A or the second conductive wire 2B, the first end surface 27A and the second end surface 27B The molten layer 55 can be generated by irradiating the laser beam onto the covering member 40 disposed across the two.

In the rectangular conducting wire connection method according to some embodiments, in the welding step S7, as shown in FIG. 12, the laser beam 51 is scanned and irradiated to melt the entire cover member 40. A molten layer 55 may be generated in which the end portion 25 of the first conducting wire 2A and the end portion 25 of the second conducting wire 2B are melted.
Thereby, the above-mentioned molten layer can be efficiently generated.

In the method for connecting rectangular conductive wires according to some embodiments, in the welding step S7, a region of the cover member 40 where the edge 27a of the first end surface 27A and the edge 27a of the second end surface 27B are adjacent to each other. A laser beam 51 is irradiated to the covering portion to melt the entire covering member 40 to form a molten layer 55 in which the covering member 40, the end 25 of the first conducting wire 2A, and the end 25 of the second conducting wire 2B are melted. You may also generate one.
Thereby, it is possible to suppress the shape of the above-mentioned molten layer 55 from being different between the first conducting wire 2A side and the second conducting wire 2B side. That is, it is possible to suppress the shape of the molten layer 55 from becoming a distorted shape such as being biased toward either of the two ends 25 of the first conductive wire 2A and the second conductive wire 2B.

In the method for connecting rectangular conductive wires according to some embodiments, in the arrangement step S5, at least a portion of the first end surface 27A and the second end surface 27B is straddled over the first end surface 27A and the second end surface 27B facing upward, respectively. It is preferable to arrange the cover member 40 so as to cover the.
This reduces the need to temporarily fasten the placed cover member 40 to the first conductive wire 2A and the second conductive wire 2B, and it is possible to suppress the effort and cost required for temporary fastening.
Note that, for example, when the first end surface 27A and the second end surface 27B face downward, in the arrangement step S5, the cover member 40 placed across the first end surface 27A and the second end surface 27B is placed over the first conductive wire 2A. It is best to temporarily fix it to the second conducting wire 2B.

In the method for connecting rectangular conductive wires according to some embodiments, in the arrangement step S5, the covering member 40 whose end facing portion 41 has a thickness of 0.1 mm or more and 0.5 mm or less is connected to the first end surface 27A and the second end surface 27A. It is preferable to arrange it so as to straddle the end surface 27B.

As a result of intensive study by the inventors, if the plate thickness of the end facing portion 41 is 0.1 mm or more, the gap 17 between the end 25 of the first conducting wire 2A and the end 25 of the second conducting wire 2B It has been found that even if the irradiated laser beam is present, it is possible to prevent the irradiated laser beam from penetrating the cover member 40 and passing through the gap 17. Further, as a result of intensive studies by the inventors, the time required to generate the above-mentioned molten layer 55 hardly changes depending on the presence or absence of the cover member 40 as long as the thickness of the end facing portion 41 is 0.5 mm or less. That's what I found out.
Therefore, according to the method for connecting rectangular conductive wires according to some embodiments, the above-mentioned molten layer 55 can be efficiently generated.

In the method for connecting square conductive wires according to some embodiments, in the arrangement step S5, a cover member 40 made of the same material as the first conductive wire 2A and the second conductive wire 2B is attached to the first end surface 27A and the second end surface 27B. It is best to place them astride each other.
Thereby, the composition of the molten layer 55 becomes the same as that of the first conducting wire 2A and the second conducting wire 2B, so that the influence on the electrical characteristics can be suppressed.

In addition, in the connection method of the rectangular conducting wire according to some embodiments, in the arrangement step S5, the covering member 40, which is made of a different material from the first conducting wire 2A and the second conducting wire 2B, is connected to the first end surface 27A and the second end surface 27B. It may be placed across.
Thus, for example, if the cover member 40 is made of a material whose laser beam absorption rate is higher than that of the first conductive wire 2A and the second conductive wire 2B, the molten layer 55 can be efficiently generated.

In the method for connecting square conductive wires according to some embodiments, in the arrangement step S5, the first end surface 27A of the first conductive wire 2A having a length of one side of the rectangular cross section of 1 mm or more and 5 mm or less, and one side of the rectangular cross section. The cover member 40 may be disposed astride the second end surface 27B of the second conducting wire 2B having a length of 1 mm or more and 5 mm or less.

In the method for connecting rectangular conductive wires according to some embodiments, in the insertion step S1, one slot 15 out of a plurality of slots 15 in the stator core 11 of the rotating electrical machine 1 is inserted into a rectangular shape from one end to the other end. It is preferable to include a step of inserting the first conductive wire 2A having a cross section and causing the first end surface 27A of the first conductive wire 2A to protrude from the other end to the outside of the one slot 15. In addition, in the method for connecting rectangular conductive wires according to some embodiments, in the insertion step S1, a second conductive wire having a rectangular cross section from one end to the other end of another slot 15 different from the one slot 15 is inserted. 2B and causing the second end surface 27B of the second conductive wire 2B to protrude from the other end to the outside of the other slot 15.
This method of connecting rectangular conducting wires can efficiently connect the windings of the stator of a rotating electric machine.

The present invention is not limited to the embodiments described above, and also includes forms in which modifications are added to the embodiments described above, and forms in which these forms are appropriately combined.
For example, the methods for connecting rectangular conductive wires according to some of the embodiments described above may be applied to connection of conductive wires other than the rectangular conductive wire 2 of the rotating electric machine 1.
Further, in some embodiments described above, as shown in FIG. 7, for example, the cover member 40 straddles the first end surface 27A and the second end surface 27B and covers the entire first end surface 27A and the second end surface 27B. There is. However, in some embodiments, the cover member 40 does not necessarily have to cover the entire first end surface 27A and second end surface 27B, and may be able to prevent the laser beam 51 from passing through the gap 17 described above. For example, it is sufficient to cover at least a portion of the first end surface 27A and the second end surface 27B.

1 Rotating electrical machine 2 Square wire (square conductor wire)
2A First conducting wire 2B Second conducting wire 10 Stator 11 Stator core 13 Stator winding 15 Slot 20 Segment conductor 20A First segment conductor 20B Second segment conductor 25 End portion 27 End surface 27A First end surface 27B Second end surface 40 Cover Member 41 End facing part 43 Side facing part 51 Laser beam 55 Melted layer 57 Connection part

Claims (11)

With the first end surface of the first conductive wire having a rectangular cross section and the second end surface of the second conductive wire having a rectangular cross section being adjacent to each other, the first end surface and arranging a cover member to cover at least a portion of the second end surface;
An energy beam is irradiated to the covering member disposed across the first end surface and the second end surface, melting the entire covering member, and melting the covering member, the end of the first conductive wire, and the first conductive wire. generating a molten layer in which the ends of the two conductive wires are fused;
Equipped with
The step of arranging the cover member includes an end facing portion formed to face the first end face and the second end face, and at least a portion of the side surface of the first conductive wire and the second conductive wire. A method for connecting a rectangular conducting wire, comprising arranging the cover member having side facing portions formed in the following manner so that the end facing portions cover at least a portion of the first end face and the second end face. The step of arranging the cover member includes placing the cover member across the first end face and the second end face, which is disposed at a position protruding from the first end face in the extending direction of the second conductive wire. A method for connecting rectangular conductive wires according to claim 1 . The step of generating the melted layer includes scanning and irradiating the energy beam to melt the entire covering member so that the covering member, the end of the first conductive wire, and the end of the second conductive wire are irradiated with the energy beam while scanning. 3. The method for connecting rectangular conductive wires according to claim 1 , wherein a molten layer is formed. The step of generating the molten layer includes irradiating the energy beam to a portion of the covering member that covers a region where the edge of the first end surface and the edge of the second end surface are adjacent to each other. The angle according to any one of claims 1 to 2 , wherein the entire covering member is melted to produce a molten layer in which the covering member, an end of the first conductive wire, and an end of the second conductive wire are melted. How to connect type conductors. 2. The step of arranging the covering member includes arranging the covering member so as to span over the first end face and the second end face facing upward, respectively, and cover at least a portion of the first end face and the second end face. 5. A method for connecting a rectangular conducting wire according to any one of items 1 to 4 . The step of arranging the cover member includes placing the cover member, the end facing portion of which is formed to face the first end face and the second end face, has a plate thickness of 0.1 mm or more and 0.5 mm or less. The method for connecting rectangular conductive wires according to any one of claims 1 to 5 , wherein the rectangular conductive wire is arranged across the first end surface and the second end surface. 7. The step of arranging the covering member includes arranging the covering member, which is made of the same material as the first conductive wire and the second conductive wire, across the first end surface and the second end surface. The method for connecting the rectangular conductor described in item (1) above. Any one of claims 1 to 6 , wherein the step of arranging the covering member includes arranging the covering member, which is made of a different material from the first conductive wire and the second conductive wire, across the first end surface and the second end surface. A method for connecting a rectangular conductor according to item 1. The step of arranging the cover member includes the step of arranging the first end face of the first conductive wire, in which the length of one side of the rectangular cross section is 1 mm or more and 5 mm or less; The method for connecting a rectangular conductive wire according to any one of claims 1 to 8 , wherein the cover member is arranged astride the second end surface of the second conductive wire. Inserting the first conductive wire from one end of one of the plurality of slots toward the other end in a stator core of a rotating electric machine, and protruding the first end surface from the other end to the outside of the one slot. the step of
Inserting the second conductive wire from one end to the other end of another slot different from the one slot to cause the second end surface to protrude from the other end to the outside of the other slot;
arranging the first end surface and the second end surface protruding to the outside of the slot adjacent to each other;
Furthermore,
10. The method for connecting rectangular conductive wires according to claim 1, wherein the step of arranging the cover members is performed after the step of arranging the cover members next to each other. A first conductive wire having a rectangular cross section is inserted from one end of one slot of a plurality of slots in a stator core of a rotating electric machine toward the other end, and the first end surface of the first conductive wire is passed from the other end to the a step of protruding to the outside of the first slot;
A second conductive wire having a rectangular cross section is inserted from one end of another slot different from the first slot toward the other end, and a second end surface of the second conductor is extended from the other end to the outside of the other slot. A step to make it stand out;
arranging the first end surface and the second end surface protruding to the outside of the slot adjacent to each other;
arranging a cover member so as to cover at least a portion of the first end surface and the second end surface, spanning the first end surface and the second end surface that are arranged next to each other;
An energy beam is irradiated to the covering member disposed across the first end surface and the second end surface, melting the entire covering member, and melting the covering member, the end of the first conductive wire, and the first conductive wire. generating a molten layer in which the ends of the two conductive wires are fused;
Equipped with
The step of arranging the cover member includes an end facing portion formed to face the first end face and the second end face, and at least a portion of the side surface of the first conductive wire and the second conductive wire. A method for manufacturing a stator for a rotating electric machine, wherein the cover member having a side facing portion formed as shown in the figure is arranged so that the end facing portion covers at least a portion of the first end face and the second end face. .