Busbar units, stators, motors

Abstract

To provide a busbar unit with excellent productivity.SOLUTION: A busbar unit applicable to a stator having a two-system connection configuration includes a busbar holder and a busbar 34 . Each busbar has a main wire portion extending in a plane perpendicular to the central axis with the plate surface facing the axial direction, and a connection terminal portion connected to the end of the main wire portion. With respect to a first imaginary line passing through the central axis of the stator when viewed in the axial direction as an axis of symmetry, the main line portion of a first U-phase busbar 341U and the main line portion of a second U-phase busbar 342U have a line symmetrical shape the main line portion of a first V-phase busbar 341V and the main line portion of a second V-phase busbar 342V have a line-symmetrical shape, and the main line portion of a first W-phase busbar 341W and the main line portion of a second W-phase busbar 342W have a line-symmetrical shape.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a busbar unit, a stator, and a motor. [Background technology]

[0002] There is known a three-phase motor that has redundancy achieved by a multiple-system connection configuration. A busbar unit having multiple busbars is used to connect the coils inside the motor (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6706583 Summary of the Invention [Problem to be solved by the invention]

[0004] In motors with multiple wiring systems, the coils are connected independently for each system, which means that a large number of bus bars are used. Furthermore, because the multiple bus bars have different shapes, many dies are required to manufacture the bus bars, which creates productivity issues in terms of efficiency and cost. [Means for solving the problem]

[0005] According to one aspect of the present invention, there is provided a busbar unit applicable to a stator having a two-system connection configuration. The busbar unit includes a busbar holder arranged on one axial side of a stator core positioned around a central axis of the stator, and a plurality of busbars made of plate-shaped conductors fixed to the busbar holder. The plurality of busbars include a first U-phase busbar and a second U-phase busbar constituting a U-phase busbar group, a first V-phase busbar and a second V-phase busbar constituting a V-phase busbar group, and a first W-phase busbar and a second W-phase busbar constituting a W-phase busbar group. Each of the busbars has a main line portion extending in a plane perpendicular to the central axis with the plate surface facing the axial direction, and a connection terminal portion connected to an end of the main line portion. When viewed in the axial direction, with a first virtual line passing through the central axis of the stator as an axis of symmetry, the main line portion of the first U-phase busbar and the main line portion of the second U-phase busbar have shapes that are line-symmetrical to each other, the main line portion of the first V-phase busbar and the main line portion of the second V-phase busbar have shapes that are line-symmetrical to each other, and the main line portion of the first W-phase busbar and the main line portion of the second W-phase busbar have shapes that are line-symmetrical to each other. Effect of the Invention

[0006] According to an aspect of the present invention, a busbar unit having excellent productivity is provided. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a cross-sectional view of a motor according to an embodiment. [Diagram 2] FIG. 2 is a perspective view of the busbar unit. [Diagram 3] FIG. 3 is a plan view of the busbar unit. [Figure 4] FIG. 4 is a plan view showing the bus bar group. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. A motor 1 according to an embodiment will be described with reference to FIGS. In this embodiment, the direction in which the central axis J of the motor 1 shown in FIG. 1 extends is simply referred to as the "axial direction". In this embodiment, the axial direction is the up-down direction. The upper side (+Z) corresponds to one axial side, and the lower side (-Z) corresponds to the other axial side. Moreover, the radial direction centered on the central axis J is simply referred to as the "radial direction". Within the radial direction, the direction approaching the central axis J is referred to as the radial inner side, and the direction away from the central axis J is referred to as the radial outer side. In this embodiment, the radial inner side corresponds to one radial side, and the radial outer side corresponds to the other radial side. Moreover, the circumferential direction centered on the central axis J is simply referred to as the "circumferential direction". Note that the terms "upper" and "lower" are simply names used to describe the relative positional relationships of the various parts, and the actual positional relationships may be other than those indicated by these names.

[0009] The motor 1 of this embodiment is mounted, for example, on an electric power steering device (not shown). The electric power steering device is mounted on a steering mechanism for wheels of an automobile. The electric power steering device is a device that reduces steering force by using a motor.

[0010] As shown in Fig. 1, the motor 1 of this embodiment includes a rotor 20 centered on a central axis J, a stator 30 disposed radially outward of the rotor 20, a housing 11, a plurality of bearings 15, 16, and a rotation detection unit 60 that detects the rotation of the rotor 20. The rotation detection unit 60 is, for example, a resolver. The rotation detection unit 60 has a resolver rotor 61 and a resolver stator 62. The rotation detection unit 60 is not limited to a resolver, and may be a type that uses a Hall element or an MR element.

[0011] The motor 1 is an inner rotor type motor. The rotor 20 rotates about a central axis J relative to the stator 30. Although not specifically shown, the motor 1 may include a board that controls the rotation of the rotor 20.

[0012] The housing 11 accommodates the rotor 20 and the stator 30. The housing 11 is cylindrical and extends in the axial direction. The housing 11 has a peripheral wall 11a, a top wall 11b, a bottom wall 11c, and a bearing retaining wall portion 11d. The peripheral wall 11a is cylindrical and extends in the axial direction. The top wall 11b closes an upper opening of the peripheral wall 11a. The bottom wall 11c closes a lower opening of the peripheral wall 11a. The bottom wall 11c holds a bearing 16. The bearing retaining wall portion 11d is fixed to the peripheral wall 11a. The bearing retaining wall portion 11d holds a bearing 15.

[0013] The rotor 20 has a shaft 21, a rotor core 22, and a magnet 23. The shaft 21 is cylindrical and extends in the axial direction. The shaft 21 may be cylindrical and extends in the axial direction. The shaft 21 is supported by a plurality of bearings 15, 16 so as to be rotatable about a central axis J. The plurality of bearings 15, 16 are spaced apart from one another in the axial direction and supported by the housing 11. That is, the shaft 21 is supported by the housing 11 via the plurality of bearings 15, 16.

[0014] The rotor core 22 is cylindrical and extends in the axial direction. The rotor core 22 has an outer diameter larger than that of the shaft 21. The rotor core 22 has an axial length smaller than that of the shaft 21. The inner peripheral surface of the rotor core 22 is fixed to the outer peripheral surface of the shaft 21. The rotor core 22 is fixed to the shaft 21 by press-fitting, adhesive bonding, or the like. The rotor core 22 is located between a pair of bearings 15, 16 in the axial direction. The magnet 23 is fixed to the outer periphery of the rotor core 22.

[0015] The stator 30 faces the rotor 20 with a radial gap therebetween. The stator 30 surrounds the rotor 20 from the radial outside over the entire circumferential direction. The stator 30 includes a stator core 31, an insulator 32, a coil 33, and a busbar unit .

[0016] The stator core 31 is annular about the central axis J. The stator core 31 is cylindrical and extends in the axial direction. The stator core 31 surrounds the rotor 20 from the radially outer side. The stator core 31 is made of a plurality of electromagnetic steel plates laminated in the axial direction. The stator core 31 is fixed to the inner circumferential surface of the housing 11. The stator core 31 and the housing 11 are fixed to each other by, for example, shrink fitting or press fitting.

[0017] The stator core 31 has a core back 31a and a plurality of teeth 31b. The core back 31a is cylindrical and centered on the central axis J. A radially outer surface of the core back 31a is fixed to an inner peripheral surface of the peripheral wall 11a. The teeth 31b protrude radially inward from a radially inner surface of the core back 31a. The plurality of teeth 31b are arranged at intervals from one another in the circumferential direction. A radially inner surface of each tooth 31b faces a radially outer surface of the rotor 20 with a gap therebetween.

[0018] The insulator 32 is attached to the stator core 31. The insulator 32 is made of an insulating material. The insulator 32 is made of, for example, resin. The insulator 32 is attached to each of the multiple teeth 31b. The coil 33 is attached to the stator core 31 via the insulator 32. A plurality of coils 33 are provided and aligned in the circumferential direction.

[0019] The motor 1 of this embodiment is a three-phase motor. The three phases are a U phase, a V phase, and a W phase. In the case of a three-phase motor, each of the coils 33 of the U phase, the V phase, and the W phase is electrically connected to a busbar unit 36.

[0020] 1, the busbar unit 36 ​​is located on the upper side (+Z side) of the stator core 31. In the present embodiment, the busbar unit 36 ​​is located between the stator core 31 and the bearing retaining wall portion 11d. The busbar unit 36 ​​may be located above the bearing retaining wall portion 11d.

[0021] 2, the busbar unit 36 ​​includes a busbar group 34 consisting of a plurality of busbars, and a busbar holder 35 that holds the busbar group 34. The busbar group 34 includes eight busbars 341U, 341V, 341W, 341G, 342U, 342V, 342W, and 342G. In this embodiment, the busbar group 34 is insert molded into the busbar holder 35.

[0022] As shown in Fig. 3, the busbar holder 35 has a holder main body 351 having an annular shape when viewed in the axial direction, three support legs 352 protruding radially outward from the outer circumferential surface of the holder main body 351, and a connector portion 353 protruding radially outward from the outer circumferential surface of the holder main body 351. The busbar holder 35 is made of resin. Ends of a plurality of busbars protrude radially outward from the outer circumferential surface of the busbar holder 35. Fig. 4 shows the busbar group 34 arranged to be held by the busbar holder 35. Each busbar constituting the busbar group 34 extends circumferentially inside the busbar holder 35, and at least a portion of a connection terminal portion described later and a coil wiring portion and an external power supply wiring portion described later are exposed to the outside of the busbar holder 35.

[0023] As shown in FIG. 3, the support legs 352 are disposed at three positions on the holder body 351. The three support legs 352 are disposed at 120° intervals in the circumferential direction when viewed from the axial direction. The support legs 352 extend radially outward from the outer circumferential surface of the holder body 351 and are L-shaped so as to bend downward at the radially outer end. The lower end of the support legs 352 contacts the stator core 31 or the insulator 32. The support legs 352 position the busbar unit 36 ​​in the axial direction relative to the stator core 31 or the insulator 32. The number of the support legs 352 may be two or less or four or more. The busbar holder 35 may be configured without the support legs 352.

[0024] The busbar unit 36 ​​is configured to be connectable to two systems of three-phase coils. FIG. 3 shows a schematic coil configuration of the motor 1 of this embodiment. The six coils 33 are configured of two systems of three-phase coils. That is, the motor 1 has a first system coil group 331 including one set of a U-phase coil 33U, a V-phase coil 33V, and a W-phase coil 33W, and a second system coil group 332 including another set of a U-phase coil 33U, a V-phase coil 33V, and a W-phase coil 33W. The positions and the number of the coils 33 are not limited to the form shown in FIG. 3. For example, each of the U-phase coil 33U, the V-phase coil 33V, and the W-phase coil 33W may be configured of a plurality of coils.

[0025] 4, the busbar group 34 has a first system busbar group 341 and a second system busbar group 342. The first system busbar group 341 has a first U-phase busbar 341U, a first V-phase busbar 341V, a first W-phase busbar 341W, and a first neutral point busbar 341G. The second system busbar group 342 has a second U-phase busbar 342U, a second V-phase busbar 342V, a second W-phase busbar 342W, and a second neutral point busbar 342G.

[0026] That is, busbar unit 36 ​​has a plurality of U-phase busbars, a plurality of V-phase busbars, and a plurality of W-phase busbars. More specifically, busbar group 34 includes first U-phase busbar 341U and second U-phase busbar 342U constituting the U-phase busbar group, first V-phase busbar 341V and second V-phase busbar 342V constituting the V-phase busbar group, and first W-phase busbar 341W and second W-phase busbar 342W constituting the W-phase busbar group.

[0027] The three coils of the first system coil group 331 shown in Fig. 3 are connected to the first system busbar group 341. The U-phase coil 33U of the first system coil group 331 is connected to the first U-phase busbar 341U and the first neutral point busbar 341G. The V-phase coil 33V of the first system coil group 331 is connected to the first V-phase busbar 341V and the first neutral point busbar 341G. The W-phase coil 33W of the first system coil group 331 is connected to the first W-phase busbar 341W and the first neutral point busbar 341G.

[0028] The three coils of the second system coil group 332 are connected to the second system busbar group 342. The U-phase coil 33U of the second system coil group 332 is connected to the second U-phase busbar 342U and the second neutral point busbar 342G. The V-phase coil 33V of the second system coil group 332 is connected to the second V-phase busbar 342V and the second neutral point busbar 342G. The W-phase coil 33W of the second system coil group 332 is connected to the second W-phase busbar 342W and the second neutral point busbar 342G.

[0029] 4, the first U-phase busbar 341U has a main line portion 41U extending in a plane perpendicular to the central axis with the plate surface facing the axial direction, a connection terminal portion Tc for connecting a coil located at one end of the main line portion 41U, and a connection terminal portion Te for connecting an external power source located at the other end of the main line portion 41U. The main line portion 41U has a plate surface facing the axial direction and a side surface facing a direction perpendicular to the axial direction. The main line portion 41U also has an arc portion 1aU extending in an arc shape along the circumferential direction around the central axis J, a coil wiring portion 1bU extending linearly from one end of the arc portion 1aU toward the outer periphery of the busbar unit 36, and an external power source wiring portion 1cU extending linearly from the other end of the arc portion 1aU toward the outer periphery of the busbar unit 36.

[0030] The second U-phase busbar 342U, like the first U-phase busbar 341U, has a main line portion 42U, a connection terminal portion Tc for connecting a coil, and a connection terminal portion Te for connecting an external power supply. The main line portion 42U has a plate surface facing the axial direction and a side surface facing a direction perpendicular to the axial direction. The main line portion 42U also has an arc portion 2aU extending in an arc shape along the circumferential direction around the central axis J, a coil wiring portion 2bU extending linearly from one end of the arc portion 2aU toward the outer periphery of the busbar unit 36, and an external power supply wiring portion 2cU extending linearly from the other end of the arc portion 2aU toward the outer periphery of the busbar unit 36.

[0031] The first V-phase busbar 341V has a main line portion 41V extending in a plane perpendicular to the central axis with the plate surface facing the axial direction, a connection terminal portion Tc for connecting a coil located at one end of the main line portion 41V, and a connection terminal portion Te for connecting an external power source located at the other end of the main line portion 41V. The main line portion 41V has a plate surface facing the axial direction and a side surface facing a direction perpendicular to the axial direction. The main line portion 41V also has an arc portion 1aV extending in an arc shape along the circumferential direction around the central axis J, a coil wiring portion 1bV extending linearly from one end of the arc portion 1aV to the outer periphery of the busbar unit 36, and an external power wiring portion 1cV extending linearly from the other end of the arc portion 1aV to the outer periphery of the busbar unit 36.

[0032] The second V-phase busbar 342V, like the first V-phase busbar 341V, has a main line portion 42V, a connection terminal portion Tc for connecting a coil, and a connection terminal portion Te for connecting an external power supply. The main line portion 42V has a plate surface facing the axial direction and a side surface facing a direction perpendicular to the axial direction. The main line portion 42V also has an arc portion 2aV extending in an arc shape along the circumferential direction around the central axis J, a coil wiring portion 2bV extending linearly from one end of the arc portion 2aV to the outer periphery of the busbar unit 36, and an external power supply wiring portion 2cV extending linearly from the other end of the arc portion 2aV to the outer periphery of the busbar unit 36.

[0033] The first W-phase busbar 341W has a main line portion 41W extending in a plane perpendicular to the central axis with the plate surface facing the axial direction, a connection terminal portion Tc for connecting a coil located at one end of the main line portion 41W, and a connection terminal portion Te for connecting an external power source located at the other end of the main line portion 41W. The main line portion 41W has a plate surface facing the axial direction and a side surface facing a direction perpendicular to the axial direction. The main line portion 41W also has an arc portion 1aW extending in an arc shape along the circumferential direction around the central axis J, a coil wiring portion 1bW extending linearly from one end of the arc portion 1aW to the outer periphery of the busbar unit 36, and an external power wiring portion 1cW extending linearly from the other end of the arc portion 1aW to the outer periphery of the busbar unit 36.

[0034] The second W-phase busbar 342W, like the first W-phase busbar 341W, has a main line portion 42W, a connection terminal portion Tc for connecting a coil, and a connection terminal portion Te for connecting an external power supply. The main line portion 42W has a plate surface facing the axial direction and a side surface facing a direction perpendicular to the axial direction. The main line portion 42W also has an arc portion 2aW extending in an arc shape along the circumferential direction around the central axis J, a coil wiring portion 2bW extending linearly from one end of the arc portion 2aW to the outer periphery of the busbar unit 36, and an external power supply wiring portion 2cW extending linearly from the other end of the arc portion 2aW to the outer periphery of the busbar unit 36.

[0035] The first neutral point busbar 341G has a main line portion 41G extending in a plane perpendicular to the central axis with the plate surface facing the axial direction, one and other ends of the main line portion 41G, and three connection terminal portions Tc for connecting coils located in the circumferential center of the main line portion 41G. The main line portion 41G has a plate surface facing the axial direction and a side surface facing a direction perpendicular to the axial direction. The main line portion 41G also has an arc portion 1aG extending in an arc shape along the circumferential direction around the central axis J, one and other ends of the arc portion 1aG, and three coil wiring portions 1bG extending in a straight line from the circumferential center to the outer periphery of the busbar unit 36.

[0036] The second neutral point busbar 342G, like the first neutral point busbar 341G, has a main line portion 42G and three connection terminal portions Tc for connecting coils. The main line portion 42G has a plate surface facing the axial direction and a side surface facing a direction perpendicular to the axial direction. The main line portion 42G also has an arc portion 2aG extending in an arc shape along the circumferential direction around the central axis J, and three coil wiring portions 2bG extending in a straight line from one and the other ends of the arc portion 2aG and the circumferential center portion to the outer periphery of the busbar unit 36.

[0037] The busbar unit 36 ​​may be configured without the first neutral point busbar 341G and the second neutral point busbar 342G. Using the first neutral point busbar 341G and the second neutral point busbar 342G makes it easier to simplify the wiring structure of the jumper wires that connect the coils 33 together, which is advantageous for improving productivity.

[0038] 4, the multiple bus bars constituting the bus bar group 34 are arranged in the circumferential direction centered on the central axis J. Of the multiple bus bars, the first W-phase bus bar 341W and the second W-phase bus bar 342W are located at the radially innermost positions.

[0039] First V-phase bus bar 341V and first neutral point bus bar 341G are arranged radially outward from first W-phase bus bar 341W. First U-phase bus bar 341U is arranged radially outward from first V-phase bus bar 341V.

[0040] A second V-phase bus bar 342V and a second neutral point bus bar 342G are arranged radially outward from second W-phase bus bar 342W. A second U-phase bus bar 342U is arranged radially outward from second V-phase bus bar 342V.

[0041] As shown in FIG. 4, the first system busbar group 341 and the second system busbar group 342 are respectively arranged in two adjacent regions with a first virtual line VL1 passing through the central axis J as a boundary when viewed in the axial direction. Furthermore, in this embodiment, the first U-phase busbar 341U and the second U-phase busbar 342U have shapes that are line-symmetrical with respect to the first virtual line VL1 as an axis of symmetry, and are arranged at positions that are line-symmetrical with respect to the first virtual line VL1 as an axis of symmetry. Similarly, the first V-phase busbar 341V and the second V-phase busbar 342V have shapes that are line-symmetrical with respect to the first virtual line VL1 as an axis of symmetry, and are arranged at positions that are line-symmetrical with respect to the first virtual line VL1 as an axis of symmetry. The first W-phase busbar 341W and the second W-phase busbar 342W have shapes that are line-symmetrical with respect to the first virtual line VL1 as an axis of symmetry, and are arranged at positions that are line-symmetrical with respect to the first virtual line VL1 as an axis of symmetry. First neutral point busbar 341G and second neutral point busbar 342G have shapes that are line-symmetrical with respect to first virtual line VL1, and are disposed at line-symmetrical positions.

[0042] The busbars are manufactured by bending blanks obtained by punching out a metal plate with a die. In this embodiment, two busbars arranged at symmetrical positions across the first virtual line VL1 have shapes that are line-symmetrical to each other, and therefore these two busbars can be manufactured using a common blank. That is, the first U-phase busbar 341U and the second U-phase busbar 342U can be manufactured from a common blank. Similarly, the first V-phase busbar 341V and the second V-phase busbar 342V, the first W-phase busbar 341W and the second W-phase busbar 342W, and the first neutral point busbar 341G and the second neutral point busbar 342G can also be manufactured using a common blank.

[0043] According to this embodiment, the eight bus bars constituting the bus bar unit 36 ​​can be manufactured from four types of blanks. This makes it possible to reduce the number of dies used to manufacture the bus bars, enabling the bus bars to be manufactured efficiently and at low cost. This allows the productivity of the bus bar unit 36 ​​to be improved.

[0044] In this embodiment, the busbars having line-symmetric shapes are arranged in line-symmetric positions about the first virtual line VL1. With this configuration, the first busbar group 341 and the second busbar group 342 are arranged in line-symmetric positions about the first virtual line VL1. The busbar holder 35 that holds the busbar group 34 can be easily formed into a ring shape that is close to a perfect circle, and can be easily arranged above the ring-shaped stator core 31.

[0045] In the present embodiment, both the shape and the arrangement of the paired busbars are configured to be line-symmetrical with respect to the first virtual line VL1, but the present invention is not limited to this configuration. The first U-phase busbar 341U and the second U-phase busbar 342U only need to have their main line portions 41U and 42U each having a shape that is line-symmetrical with respect to the first virtual line VL1. The same is true for the first V-phase busbar 341V and the second V-phase busbar 342V, the first W-phase busbar 341W and the second W-phase busbar 342W, and the first neutral point busbar 341G and the second neutral point busbar 342G. If the main line portions have shapes that are line-symmetrical with each other, it is possible to use the same blank for manufacturing the busbars, thereby improving the manufacturing efficiency of the busbars.

[0046] The shapes of the connection terminal portions Tc, Te, which are portions other than the main line portion, are changed according to the position and orientation of the lead wire extending from the coil 33. For example, the orientation of the opening of the coil connection connection terminal portion Tc that holds the lead wire from the coil 33 may differ between the first U-phase bus bar 341U and the second U-phase bus bar 342U. Even in this case, the two blanks, which differ only in shape at the portions forming the connection terminals Tc and Te, can be manufactured by using a common punched shape from a metal plate and performing only a small amount of cutting after punching, thereby reducing the number of dies used to manufacture the blanks.

[0047] In this embodiment, as shown in Fig. 4, the first U-phase busbar 341U, the second U-phase busbar 342U, the first V-phase busbar 341V, the second V-phase busbar 342V, the first W-phase busbar 341W, the second W-phase busbar 342W, the first neutral point busbar 341G, and the second neutral point busbar 342G are arranged at positions where they do not overlap each other when viewed from the axial direction. The eight busbars are arranged at positions where they overlap at least one other busbar when viewed from the radial direction. In this embodiment, the main line portions of the eight busbars are arranged on a common plane with the plate surfaces facing the axial direction. According to this configuration, the multiple busbars can be arranged in positions where they overlap when viewed from the radial direction, and the multiple busbars are arranged with their plate surfaces facing the axial direction, which significantly reduces the axial thickness of the busbar unit 36. By using the busbar unit 36 ​​of this embodiment, it is possible to realize a stator 30 and a motor 1 that are compact in the axial direction.

[0048] As shown in FIG. 4, each bus bar constituting bus bar group 34 has a wide portion that protrudes in a direction perpendicular to the axial direction from a side surface of the bus bar when viewed in the axial direction.

[0049] The first U-phase busbar 341U has a wide portion 1dU that protrudes from a side surface of the external power supply wiring portion 1cU toward the external power supply wiring portion 1cV (right side in FIG. 4) at an intersection between the arc portion 1aU and the external power supply wiring portion 1cU. The second U-phase busbar 342U has a wide portion 2dU that protrudes from a side surface of the external power supply wiring portion 2cU toward the external power supply wiring portion 2cV (left side in FIG. 4) at an intersection between the arc portion 2aU and the external power supply wiring portion 2cU.

[0050] The first U-phase busbar 341U has two through holes H11, H12 penetrating the main line portion 41U in the plate thickness direction (axial direction) at the position of the wide portion 1dU. The second U-phase busbar 342U has two through holes H21, H22 penetrating the main line portion 42U in the plate thickness direction at the position of the wide portion 2dU. The two through holes H11, H12 of the first U-phase busbar 341U are aligned along the direction in which the external power supply wiring portion 1cU extends. The two through holes H21, H22 of the second U-phase busbar 342U are aligned along the direction in which the external power supply wiring portion 2cU extends. The through holes H11, H12 are holes into which support pins are inserted to fix each busbar in a mold when the busbar group 34 is insert-molded into the busbar holder 35. The same applies to the other through holes H13 to H19 and through holes H23 to H29 described later.

[0051] The first V-phase busbar 341V has a wide portion 1dV at an inner corner of a position where the arc portion 1aV and the coil wiring portion 1bV intersect. The first V-phase busbar 341V has a wide portion 1eV at an intersection of the arc portion 1aV and the external power supply wiring portion 1cV, which protrudes from a side surface of the external power supply wiring portion 1cV toward the external power supply wiring portion 1cW (the right side in FIG. 4). The first V-phase busbar 341V has two through holes H13 and H14 that penetrate the wide portions 1dV and 1eV in the plate thickness direction, respectively.

[0052] The second V-phase busbar 342V has a wide portion 2dV at an inner corner of a position where the arc portion 2aV and the coil wiring portion 2bV intersect. The second V-phase busbar 342V has a wide portion 2eV at an intersection of the arc portion 2aV and the external power supply wiring portion 2cV, which protrudes from a side surface of the external power supply wiring portion 2cV toward the external power supply wiring portion 2cW (left side in FIG. 4). The second V-phase busbar 342V has two through holes H23 and H24 that penetrate the wide portions 2dV and 2eV in the plate thickness direction.

[0053] The first W-phase busbar 341W has a wide portion 1dW at an inner corner of a position where the arc portion 1aW and the coil wiring portion 1bW intersect. The first W-phase busbar 341W has a wide portion 1eW at an intersection of the arc portion 1aW and the external power supply wiring portion 1cW, which protrudes from a side surface of the external power supply wiring portion 1cW to the external power supply wiring portion 1cV side (left side in FIG. 4). The first W-phase busbar 341W has a wide portion 1fW at a center of the arc portion 1aW, which protrudes radially outward from a side surface of the arc portion 1aW. The first W-phase busbar 341W has three through holes H15, H16, and H17 that penetrate the wide portions 1dW, 1eW, and 1fW in the plate thickness direction, respectively.

[0054] The second W-phase busbar 342W has a wide portion 2dW at an inner corner of a position where the arc portion 2aW and the coil wiring portion 2bW intersect. The second W-phase busbar 342W has a wide portion 2eW at an intersection of the arc portion 2aW and the external power supply wiring portion 2cW, which protrudes from a side surface of the external power supply wiring portion 2cW to the external power supply wiring portion 2cV side (left side in FIG. 4). The second W-phase busbar 342W has a wide portion 2fW at a center of the arc portion 2aW, which protrudes radially outward from a side surface of the arc portion 2aW. The second W-phase busbar 342W has three through holes H25, H26, and H27 that penetrate the wide portions 2dW, 2eW, and 2fW in the plate thickness direction, respectively.

[0055] The first neutral point busbar 341G has a wide portion 1dG that protrudes outward in the circumferential direction from a corner where the arc portion 1aG and the coil wiring portion 1bG on one circumferential side are connected. The first neutral point busbar 341G has a wide portion 1eG that protrudes outward in the circumferential direction from a corner where the arc portion 1aG and the coil wiring portion 1bG on the other circumferential side are connected. The first neutral point busbar 341G has two through holes H18, H19 that penetrate the wide portions 1dG, 1eG in the plate thickness direction, respectively.

[0056] The second neutral point busbar 342G has a wide portion 2dG that protrudes outward in the circumferential direction from a corner where the arc portion 2aG and the coil wiring portion 2bG on one circumferential side are connected. The second neutral point busbar 342G has a wide portion 2eG that protrudes outward in the circumferential direction from a corner where the arc portion 2aG and the coil wiring portion 2bG on the other circumferential side are connected. The second neutral point busbar 342G has two through holes H28, H29 that penetrate the wide portions 2dG, 2eG in the plate thickness direction, respectively.

[0057] According to this embodiment, each busbar belonging to busbar group 34 has a wide portion that protrudes from a side surface of each busbar in a direction perpendicular to the axial direction when viewed in the axial direction, so that even if the busbar has a through hole, the electrical resistance of the busbar can be prevented from increasing. In this embodiment, the through holes of the busbar may be located in the wide portion of the busbar, as in the through holes H13 to H19 and H23 to H29 shown in Fig. 4, or may be located near the wide portions 1dU and 2dU, as in the through holes H11, H12, H21 and H22. By configuring the through holes to be located in the wide portion, an increase in the electrical resistance of the busbar due to the through holes is almost eliminated, so that the through holes for inserting support pins can be located in any position.

[0058] In this embodiment, wide portion 1dV of first V-phase busbar 341V, wide portion 2dV of second V-phase busbar 342V, wide portion 1dW of first W-phase busbar 341W, and wide portion 2dW of second W-phase busbar 342W are located inside the corners where the respective busbars are bent. This configuration can increase the rigidity of each busbar. It is possible to reduce the bending of the busbars, which can improve the yield of busbar unit 36 ​​and reduce defects in the coil wiring.

[0059] In this embodiment, wide portions 1dv, 1eV of first V-phase busbar 341V and wide portions 2dV, 2eV of second V-phase busbar 342V are located at both circumferential ends of first V-phase busbar 341V and second V-phase busbar 342V, respectively. Similarly, wide portions 1dW, 1eW of first W-phase busbar 341W and wide portions 2dW, 2eW of second W-phase busbar 342W are located at both circumferential ends of first W-phase busbar 341W and second W-phase busbar 342W, respectively. According to these configurations, by providing through holes in the wide portion, through holes for inserting support pins can be arranged at both ends of the elongated bus bar, so that even a relatively long bus bar can be stably held. The positional accuracy of the bus bar during insert molding can be improved. The yield of bus bar units 36 can be improved and defects in the coil wiring can be reduced.

[0060] In this embodiment, the first U-phase busbar 341U, the second U-phase busbar 342U, the first V-phase busbar 341V, the second V-phase busbar 342V, the first W-phase busbar 341W, and the second W-phase busbar 342W have external power supply wiring portions 1cU, 2cU, 1cV, 2cV, 1cW, and 2cW extending in a direction along the first virtual line VL1 in a part of the main line portions 41U, 42U, 41V, 42V, 41W, and 42W, respectively. An external power supply connection terminal portion Te extends from the tip of the external power supply wiring portions 1cU, 2cU, 1cV, 2cV, 1cW, and 2cW. The multiple external power supply wiring portions 1cU, 2cU, 1cV, 2cV, 1cW, and 2cW are arranged in a direction perpendicular to the first virtual line VL1 when viewed in the axial direction. The external power supply wiring portions 1cU, 2cU, 1cV, 2cV, 1cW, and 2cW are held by a connector portion 353 of the bus bar holder 35 shown in Figures 2 to 4. The respective tips of the external power supply wiring portions 1cU, 2cU, 1cV, 2cV, 1cW, and 2cW protrude from the connector portion 353 to the outer periphery of the bus bar unit 36. According to this configuration, the multiple external power supply wiring portions 1cU, 2cU, 1cV, 2cV, 1cW, and 2cW are housed in a partial circumferential region of the bus bar holder 35, allowing the external power supply wiring portions to be arranged compactly. The multiple external power supply wiring portions are aligned along the first virtual line VL1, allowing both the external power supply wiring portions 1cU, 1cV, and 1cW of the first bus bar group 341 and the external power supply wiring portions 2cU, 2cV, and 2cW of the second bus bar group 342 to be arranged near the first virtual line VL1. The connectors to the two external power supplies can be configured compactly.

[0061] As shown in FIG. 4, the first system external power supply wiring sections 1cV, 1cW have wide portions 1eV, 1eW protruding from opposing side surfaces, and the two wide portions 1eV, 1eW overlap each other when viewed from the extension direction of the external power supply wiring sections 1cV, 1cW. Also in the second system, the external power supply wiring portions 2cV, 2cW have wide portions 2eV, 2eW protruding from opposing side surfaces, and the two wide portions 2eV, 2eW overlap each other when viewed from the extension direction of the external power supply wiring portions 2cV, 2cW. According to these configurations, two wide portions 1eV, 1eW are arranged in the gap between adjacent external power supply wiring portions 1cV, 1cW. Two wide portions 2eV, 2eW are arranged in the gap between external power supply wiring portions 2cV, 2cW. Since the wide portions 1eV, 1eW, 2eV, 2eW can be arranged efficiently, the connector to the external power supply can be configured compactly. In addition, since the width between the external power supply wiring portions is not excessively large, molding defects of the resin in the gap between the external power supply wiring portions can be suppressed.

[0062] In this embodiment, wide portion 1dU of first U-phase bus bar 341U is disposed between adjacent external power supply wiring portions 1cU and 1cV. Wide portion 2dU of second U-phase bus bar 342U is disposed between adjacent external power supply wiring portions 2cU and 2cV. This configuration prevents the gaps between adjacent external power supply wiring portions 1cU and 1cV and the gaps between adjacent external power supply wiring portions 2cU and 2cV from becoming excessively large, and suppresses molding defects of resin from occurring in the gaps between the external power supply wiring portions. [Explanation of symbols]

[0063] 1...motor, 1cU, 1cV, 1cW, 2cU, 2cV, 2cW...external power supply wiring section, 1dG, 1dU, 1dv, 1dV, 1dW, 1eG, 1eV, 1eW, 1fW, 2dG, 2dU, 2dV, 2dW, 2eG, 2eV, 2eW, 2fW...wide section, 30...stator, 31...stator core, 34...busbar group, 35...busbar holder, 36...busbar unit, 41G, 41U, 41V, 41W, 42G, 42U, 42 V, 42W...main line section, 341G...first neutral busbar, 341U...busbar, 341U...first U-phase busbar, 341V...first V-phase busbar, 341W...first W-phase busbar, 342G...second neutral busbar, 342U...second U-phase busbar, 342V...second V-phase busbar, 342W...second W-phase busbar, H11~H19, H21~H29...through hole, J...center axis, Tc, Te...connection terminal section, VL1...first virtual line

Claims

1. A busbar unit applicable to a stator having a two-system wiring configuration, a bus bar holder disposed on one axial side of a stator core positioned around a central axis of the stator; a plurality of bus bars each having a plate-shaped conductor fixed to the bus bar holder; The plurality of bus bars include a first U-phase bus bar and a second U-phase bus bar constituting a U-phase bus bar group; a first V-phase bus bar and a second V-phase bus bar constituting a V-phase bus bar group; a first W-phase bus bar and a second W-phase bus bar constituting a W-phase bus bar group; Including, Each of the bus bars has a main line portion extending in a plane perpendicular to a central axis with a plate surface facing an axial direction, and a connection terminal portion connected to an end of the main line portion, When viewed in the axial direction, a first imaginary line passing through the central axis of the stator is used as an axis of symmetry, a main line portion of the first U-phase bus bar and a main line portion of the second U-phase bus bar have shapes that are axisymmetric to each other, a main line portion of the first V-phase bus bar and a main line portion of the second V-phase bus bar have shapes that are axisymmetric to each other, a main line portion of the first W-phase bus bar and a main line portion of the second W-phase bus bar have shapes that are axisymmetric to each other, the first U-phase bus bar, the second U-phase bus bar, the first V-phase bus bar, the second V-phase bus bar, the first W-phase bus bar, and the second W-phase bus bar each have, at a part of a main line portion thereof, an external power supply wiring portion extending in a direction along the first virtual line, The connection terminal portion for an external power supply extends from a tip of the external power supply wiring portion, The external power supply wiring portions of the plurality of bus bars are arranged in a direction perpendicular to the first imaginary line when viewed in the axial direction, each of the bus bars has a wide portion at a portion of a plate surface facing the axial direction, the wide portion protruding from a side surface of the bus bar in a direction perpendicular to the axial direction as viewed in the axial direction; At least two of the external power supply wiring portions of the plurality of bus bars have the wide portions protruding from side surfaces facing each other, the wide portions protruding from the opposing side surfaces overlap each other when viewed from a direction in which the external power supply wiring portion extends; Busbar unit.

2. the first U-phase busbar, the second U-phase busbar, the first V-phase busbar, the second V-phase busbar, the first W-phase busbar, and the second W-phase busbar are arranged at positions not overlapping with each other when viewed in the axial direction, but overlapping with at least one other busbar when viewed in the radial direction. The busbar unit according to claim 1 .

3. a main line portion of the first U-phase bus bar and a main line portion of the second U-phase bus bar are disposed at positions that are line-symmetrical with each other with respect to the first virtual line, a main line portion of the first V-phase bus bar and a main line portion of the second V-phase bus bar are disposed at positions symmetrical to each other with respect to the first virtual line, a main line portion of the first W-phase bus bar and a main line portion of the second W-phase bus bar are disposed at positions symmetrical to each other with respect to the first virtual line. The busbar unit according to claim 2 .

4. the plurality of bus bars include a first neutral point bus bar and a second neutral point bus bar that constitute a neutral point bus bar group, each of the first neutral point bus bar and the second neutral point bus bar has a main line portion extending in a plane perpendicular to a central axis with a plate surface oriented in an axial direction, and a connection terminal portion extending from an end of the main line portion; a main line portion of the first neutral point busbar and a main line portion of the second neutral point busbar have shapes that are line-symmetrical with each other with respect to the first virtual line. The busbar unit according to claim 1 .

5. the first neutral point busbar, the second neutral point busbar, the first U-phase busbar, the second U-phase busbar, the first V-phase busbar, the second V-phase busbar, the first W-phase busbar, and the second W-phase busbar are each arranged at a position not overlapping with one another when viewed in the axial direction, but overlapping with at least one other busbar when viewed in the radial direction. The busbar unit according to claim 4.

6. a main line portion of the first neutral point busbar and a main line portion of the second neutral point busbar are disposed in line-symmetrical positions with respect to the first virtual line. The busbar unit according to claim 5 .

7. each of the bus bars has a wide portion at a portion of a plate surface facing the axial direction, the wide portion protruding from a side surface of the bus bar in a direction perpendicular to the axial direction as viewed in the axial direction; The busbar unit according to claim 1 .

8. The wide portion has a through hole penetrating the bus bar in a plate thickness direction. The busbar unit according to claim 7.

9. The wide portion is located at a corner where the main line portion is bent as viewed in the axial direction. The busbar unit according to claim 7 or 8.

10. The wide portion is located at an end of the bus bar in the circumferential direction. The busbar unit according to any one of claims 7 to 9.

11. A stator comprising the busbar unit according to any one of claims 1 to 10.

12. A motor comprising the stator according to claim 11.

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