JP7192776B2 - motor - Google Patents

Description

The present invention relates to motors.

A known three-phase motor is provided with a bus bar for connecting coils (for example, Patent Document 1). On the other hand, in recent years, there has been a demand for a motor in which redundancy is ensured by forming a three-phase motor into a multi-system connection configuration.

Japanese Patent Publication No. 2016-208578

A motor having a plurality of systems has a problem that the number of bus bars increases, resulting in an increase in the size of the motor.

In view of the above problems, it is an object of one embodiment of the present invention to provide a motor that employs a plurality of systems and can be downsized.

A motor according to the present invention includes a rotor that rotates around a vertically extending central axis, a stator that faces the rotor in a radial direction with a gap therebetween, and a busbar unit that is provided above the stator. The stator has a plurality of systems of coil groups, with a U-phase coil, a V-phase coil, and a W-phase coil as one system of coil groups, and the coil groups of different systems are arranged symmetrically about a central axis. The busbar unit has a plurality of phase busbars connected to lead wires drawn out from the respective phase coils, and a busbar holder holding the plurality of phase busbars, wherein the phase busbar a busbar main body portion extending along a circumferential direction; a coil terminal located at one end of the busbar main body portion and extending in one radial direction with respect to the busbar main body portion and connected to the lead wire; and an external connection terminal positioned at the other end of the bus bar and extending upward, wherein the phase bus bar is plate-shaped and arranged with a thickness direction perpendicular to at least the axial direction of the bus bar main body, Of the plurality of phase bus bars, the phase bus bar having the longest length along the circumferential direction of the bus bar main body radially overlaps at least a portion of the other phase bus bars, and the busbar holder has a clamping portion for holding the plurality of phase busbars in a thickness direction, Among them, the phase bus bar having the longest length along the circumferential direction of the bus bar body portion is held by the clamping portion in a region that does not radially overlap other phase bus bars. .

According to one aspect of the present invention, it is possible to provide a motor that can be downsized while adopting a plurality of systems.

FIG. 1 is a cross-sectional view of a motor of one embodiment. FIG. 2 is a plan view of the stator of one embodiment. FIG. 3 is a schematic diagram showing connection of each coil of the stator of one embodiment. FIG. 4 is a schematic diagram showing two systems of Y-connection formed by the coils of one embodiment. FIG. 5 is a perspective view of the busbar unit of one embodiment. FIG. 6 is an exploded perspective view of the busbar unit of one embodiment. FIG. 7 is a plan view of the busbar unit of one embodiment. FIG. 8 is a cross-sectional view taken along line VIII--VIII of FIG. FIG. 9 is a bottom view of the busbar unit of one embodiment. 10 is a schematic cross-sectional view taken along line XX of FIG. 9. FIG. FIG. 11 is a schematic diagram showing an electric power steering device according to one embodiment.

Hereinafter, motors according to embodiments of the present invention will be described with reference to the drawings. It should be noted that the scope of the present invention is not limited to the following embodiments, and can be arbitrarily changed within the scope of the technical idea of the present invention. Also, in the drawings below, in order to make each configuration easier to understand, there are cases where the actual structure and the scale, number, etc. of each structure are different.

Each drawing shows an XYZ coordinate system as a three-dimensional orthogonal coordinate system as appropriate. In the XYZ coordinate system, the Z-axis direction is parallel to the axial direction of the central axis J shown in FIG. The X-axis direction is a direction perpendicular to the Z-axis direction and is the horizontal direction in FIG. The Y-axis direction is a direction orthogonal to both the X-axis direction and the Z-axis direction.

In the following description, the positive side in the Z-axis direction (+Z side) is called the "upper side", and the negative side in the Z-axis direction (-Z side) is called the "lower side". Note that the upper side and the lower side are directions used for explanation only, and do not limit the actual positional relationship and direction. In addition, unless otherwise specified, the direction parallel to the central axis J (the Z-axis direction) is simply referred to as the "axial direction" or the "vertical direction", and the radial direction around the central axis J is simply referred to as the "radial direction". The circumferential direction around the central axis J, that is, the circumference of the central axis J is simply called the "circumferential direction". Furthermore, in the following description, "planar view" means a state viewed from the axial direction.

[Motor] FIG. 1 is a sectional view of a motor 1 of this embodiment. The motor 1 of this embodiment is a three-phase AC motor. Further, the motor 1 of this embodiment is an inner rotor type motor.

The motor 1 includes a rotor 20 having a shaft 21 , a stator 30 , a busbar unit 60 , a housing 40 , an upper bearing (bearing) 6A, a lower bearing 6B, and a bearing holder 10 . The motor 1 is connected to an external device (controller) 9 via external connection terminals 71 c , 72 c , 73 c extending upward from the bus bar unit 60 . The rotation of the rotor 20 of the motor 1 is controlled by the external device 9 .

[Housing] The housing 40 is cylindrical and opens upward (+Z side). Housing 40 accommodates rotor 20 and stator 30 . Housing 40 has a tubular portion 45 , a bottom portion 49 and a lower bearing retainer 48 .

The cylindrical portion 45 surrounds the stator 30 from the radial outside. In this embodiment, the tubular portion 45 is cylindrical with the central axis J as the center. The bottom portion 49 is positioned at the lower end of the tubular portion 45 . Bottom portion 49 is positioned below stator 30 . The lower bearing holding portion 48 is positioned at the center of the bottom portion 49 in plan view. The lower bearing holding portion 48 holds the lower bearing 6B. The lower bearing holding portion 48 has a holding cylinder portion 48a extending axially about the central axis J, and a lower end projecting portion 48b extending radially inward from the lower end of the holding cylinder portion 48a. A hole portion 48c that penetrates in the axial direction is provided in the center of the lower end projecting portion 48b in plan view.

[Rotor] The rotor 20 rotates about the central axis J. As shown in FIG. The rotor 20 has a shaft 21 , a rotor core 24 and rotor magnets 23 . The shaft 21 is arranged along the central axis J centered on the central axis J extending in the vertical direction (axial direction). The shaft 21 is rotatably supported around the central axis J by the upper bearing 6A and the lower bearing 6B.

Rotor core 24 is fixed to shaft 21 . The rotor core 24 surrounds the shaft 21 in the circumferential direction. A rotor magnet 23 is fixed to the rotor core 24 . More specifically, the rotor magnet 23 is fixed to the outer surface of the rotor core 24 along the circumferential direction. Rotor core 24 and rotor magnet 23 rotate together with shaft 21 .

[Upper Bearing and Lower Bearing] The upper bearing 6A rotatably supports the shaft 21 provided on the rotor 20 above the rotor core 24. As shown in FIG. The upper bearing 6A is supported by a bearing holder 10. As shown in FIG. The lower bearing 6</b>B rotatably supports the shaft 21 provided on the rotor 20 below the rotor core 24 . The lower bearing 6B is supported by the lower bearing holding portion 48 of the housing 40. As shown in FIG.

[Bearing Holder] The bearing holder 10 is positioned above the stator 30 (+Z side). Moreover, the bearing holder 10 is located above the busbar unit 60 which will be described later. A bearing holder 10 holds the upper bearing 6A. Also, the bearing holder 10 is held by the cylindrical portion 45 of the housing 40 . The planar view (XY plane view) shape of the bearing holder 10 is a circular shape concentric with the central axis J, for example.

The bearing holder 10 includes a disk-shaped bearing holder main body 16, an upper bearing holding part 18 positioned radially inside the bearing holder main body 16, and a fitting cylinder positioned radially outside the bearing holder main body 16. a portion 15; The upper bearing holding portion 18, the bearing holder body portion 16, and the fitting tubular portion 15 are arranged in this order from the radially inner side toward the outer side.

The bearing holder body portion 16 extends along a plane orthogonal to the axial direction. The bearing holder body portion 16 is provided with through holes 16a through which the external connection terminals 71c, 72c, and 73c of the busbar unit 60 are inserted.

The upper bearing holding portion 18 holds the upper bearing 6A. The upper bearing holding portion 18 is positioned at the center of the bearing holder 10 in plan view. The upper bearing holding portion 18 has a holding tubular portion 18a extending axially about the central axis J, and an upper end projecting portion 18b extending radially inward from the upper end of the holding tubular portion 18a. The upper end projecting portion 18b positions the upper bearing 6A in the vertical direction. A hole portion 18c that penetrates in the axial direction is provided in the center of the upper end projecting portion 18b in plan view. The upper end of the shaft 21 is inserted through the hole 18c.

The fitting cylinder portion 15 extends downward from the outer edge of the bearing holder body portion 16 . The fitting tubular portion 15 extends in a tubular shape along the circumferential direction. The fitting tubular portion 15 is fitted to face the inner peripheral surface 45c of the tubular portion 45 in the radial direction. The bearing holder 10 is thereby fixed to the housing 40 .

[Stator] The stator 30 is annularly arranged around the central axis J. As shown in FIG. The stator 30 radially faces the rotor 20 with a gap therebetween. The stator 30 surrounds the radially outer side of the rotor 20 . Stator 30 is fixed to inner peripheral surface 45 c of tubular portion 45 of housing 40 . The stator 30 has a stator core 31 , an upper insulator (insulator) 35 , a lower insulator 34 and coils 33 .

2 is a plan view of the stator 30. FIG. 2 shows part of coil terminals 71a, 72a, 73a, 81a, and 82a of the busbar unit 60, which will be described later.

The stator core 31 is composed of a plurality of core pieces 32 annularly arranged along the circumferential direction. In the stator core 31, circumferentially adjacent core pieces 32 are connected to each other. That is, the stator core 31 is configured by connecting a plurality of core pieces 32 along the circumferential direction.

The core piece 32 has a core back portion 32a, teeth portions 32b, and an umbrella portion 32c. That is, the stator core 31 has a plurality of core back portions 32a, a plurality of tooth portions 32b, and a plurality of umbrella portions 32c. The stator core 31 of this embodiment is composed of 12 core pieces 32 . Therefore, the stator 30 of this embodiment has twelve teeth 32b. The number of core pieces 32 and teeth 32b is not limited to this.

The core back portion 32a extends along the circumferential direction. The core-back portion 32a is connected to the core-back portion 32a of the adjacent core piece 32 at the end facing the circumferential direction. The core back portions 32a adjacent to each other in the circumferential direction are joined by welding or the like. As a result, the core back portions 32a of all the core pieces 32 are annularly coupled.

The tooth portion 32b extends radially inward from the center in the circumferential direction of the core back portion 32a. A coil 33 is wound around the tooth portion 32b with an upper insulator 35 and a lower insulator 34 interposed therebetween.

The umbrella portion 32c is located at the tip (diameter direction inner end) of the tooth portion 32b. The circumferential dimension of the umbrella portion 32c is larger than the circumferential dimension of the teeth portion 32b and smaller than the circumferential dimension of the core-back portion 32a. A surface of the umbrella portion 32 c facing radially inward faces the rotor magnet 23 of the rotor 20 .

Moreover, the stator core 31 of the present embodiment is composed of a plurality of core pieces 32 as so-called split cores. However, the core piece forming the stator core 31 may be a curling core in which the adjacent core back portions 32a are partially connected to each other and bent into an annular shape after the coil 33 is wound.

As shown in FIG. 1 , the upper insulator 35 covers at least the upper side of the tooth portion 32 b on the upper surface of the stator core 31 . Similarly, the lower insulator 34 covers at least the lower side of the tooth portion 32b on the lower surface of the stator core 31 . That is, the upper insulator 35 covers the upper surface of the tooth portion 32b, and the lower insulator 34 covers the lower surface of the tooth portion 32b. Upper insulator 35 and lower insulator 34 are made of an insulating material. The upper insulator 35 and the lower insulator 34 have the same configuration except that they are provided on opposite sides of the stator core 31 in the vertical direction.

As shown in FIG. 2 , the upper insulator 35 has a plurality of insulator pieces 36 positioned above each core piece 32 . Although illustration is omitted, the lower insulator 34 has a plurality of insulator pieces 36 like the upper insulator 35 .

The insulator pieces 36 of the upper insulator 35 are provided in the same number as the core pieces 32 (12 pieces in this embodiment). One insulator piece 36 is arranged above one core piece 32 . The plurality of insulator pieces 36 are annularly arranged along the circumferential direction.

The insulator piece 36 has a base portion 36b, a first standing wall portion 36a, and a second standing wall portion 36c. The base portion 36b is positioned above the tooth portion 32b and covers the upper surface of the tooth portion 32b. The first standing wall portion 36a protrudes upward from the radially outer end portion of the base portion 36b and extends along the circumferential direction. The first standing wall portion 36a is positioned above the core back portion 32a. The second standing wall portion 36c protrudes upward from the radially inner end portion of the base portion 36b and extends along the circumferential direction. The second standing wall portion 36c is positioned above the umbrella portion 32c.

A coil 33 is wound around the base portion 36b. The first vertical wall portion 36a and the second vertical wall portion 36c face each other in the radial direction with the base portion 36b interposed therebetween. The first standing wall portion 36a and the second standing wall portion 36c guide the coil 33 wound around the base portion 36b from the radially outer side and the inner side, respectively.

The first standing wall portion 36a has a pair of end faces 36d facing both sides in the circumferential direction and an outer peripheral face 36e facing radially outward. End faces 36d of adjacent insulator pieces 36 face each other in the circumferential direction. A chamfer 36f is provided between the first standing wall portion 36a and the outer peripheral surface 36e. Between the chamfers 36f of the adjacent insulator pieces 36, V-shaped leg accommodation portions 37 are provided when viewed from the axial direction. That is, the upper insulator 35 is provided with the leg accommodation portion 37 .

Conventionally, there has been known a structure in which a recessed portion provided on an outer peripheral surface facing radially outward of one insulator piece is used as a leg accommodating portion. On the other hand, according to the present embodiment, the leg accommodating portion 37 is provided by radially abutting the chamfers 36f of the pair of insulator pieces 36 arranged in the circumferential direction. For this reason, it is not necessary to provide a recess in one insulator piece 36, and when the insulator piece 36 is manufactured by injection molding, the degree of freedom in the extraction direction of the insulator piece 36 can be increased. As a result, the insulator piece 36 can be manufactured at low cost.

The leg accommodation portion 37 is V-shaped, as viewed in the axial direction, which is open on one side in the radial direction (diametrically outward in this embodiment) and narrows toward the other side (radially inwardly in this embodiment). is. The leg accommodation portion 37 is positioned above the boundary portion between the adjacent core pieces 32 when viewed in the axial direction.

The leg portion accommodation portion 37 accommodates the leg portion 65 of the busbar unit 60 which will be described later. The leg portion 65 fits into the V-shape of the leg portion accommodating portion 37 . That is, the leg portion 65 has a V shape that narrows toward the other side in the radial direction (the radially inner side in the present embodiment) when viewed in the axial direction.

The coil 33 is configured by winding a coil wire around the tooth portion 32 b via the upper insulator 35 and the lower insulator 34 . Therefore, the plurality of coils 33 are arranged annularly along the circumferential direction.

In this embodiment, the stator 30 is provided with 12 coils 33 . The twelve coils 33 are continuously wound with a pair of coils 33 as one set. The two coils 33 that are continuously wound are connected via a connecting wire 33b. The crossover wire 33 b passes above the coil 33 . The crossover wire 33b is insulated from the coil 33 by an insulating tube (not shown).

One lead wire 33 a extends upward from each coil 33 . The lead wire 33a corresponds to the winding start and winding end of the two coils 33 which are continuously wound. Therefore, one lead wire 33 a extends from one coil 33 . The lead wire 33a is connected to coil terminals 71a, 72a, 73a, 81a, and 82a, which will be described later. The coil terminals 71a, 72a, 73a, 81a, 82a are the coil terminals 71a, 72a, 73a of the phase busbars 71, 72, 73 and the coil terminals 81a, 82a of the neutral point busbars 81, 82. ,are categorized.

FIG. 3 is a schematic diagram showing connection of each coil 33 of the stator 30. As shown in FIG. The 12 coils 33 of the stator 30 include four U-phase coils U1a, U1b, U2a and U2b, four V-phase coils V1a, V1b, V2a and V2b, and four W-phase coils W1a, W1b, W2a and W2b. and consists of

FIG. 4 is a schematic diagram showing a two-system Y-connection composed of 12 coils 33. As shown in FIG. As shown in FIG. 4 , the stator 30 includes a U-phase coil, a V-phase coil, and a W-phase coil as one coil group, and a plurality of systems (in this embodiment, two systems) of coil groups (first system of coils). It has a coil group 7 and a second system of coil group 8). That is, the stator 30 has two coil groups 7 and 8 classified into a first coil group 7 and a second coil group.

The coil group 7 of the first system has U-phase coils U1a and U1b, V-phase coils V1a and V1b, and W-phase coils W1a and W1b. The second system coil group 8 has U-phase coils U2a and U2b, V-phase coils V2a and V2b, and W-phase coils W2a and W2b. That is, two coils 33 are provided for one phase of each system. Two coils 33 of each phase of each system are connected by a connecting wire 33b. In other words, in each system, a plurality of U-phase coils, a plurality of V-phase coils, and a plurality of W-phase coils are provided, and are provided across a plurality of teeth portions 32b via connecting wires 33b.

In the coil group 7 of the first system, U-phase coils U1a and U1b, V-phase coils V1a and V1b, and W-phase coils W1a and W1b are connected to each other by Y-connection. Similarly, in coil group 8 of the second system, U-phase coils U2a and U2b, V-phase coils V2a and V2b, and W-phase coils W2a and W2b are connected to each other by Y-connection.

As shown in FIG. 3, one lead line 33a of the two U-phase coils U1a and U1b of the first system connected via a connecting wire 33b is connected to a U-phase bus bar 71A of a first system phase bus bar group 70A, which will be described later. , and the other lead wire 33 a is connected to the first system neutral point bus bar 81 .

Similarly, one lead wire 33a of the two V-phase coils V1a and V1b of the first system connected via a connecting wire 33b is connected to the V-phase bus bar 72A of the first system phase bus bar group 70A, Lead line 33 a is connected to first system neutral point bus bar 81 .

In addition, one lead wire 33a of the two W-phase coils W1a and W1b of the first system connected via the connecting wire 33b is connected to the W-phase bus bar 73A of the first system phase bus bar group 70A, and the other lead wire Line 33 a is connected to first system neutral point bus bar 81 .

As described above, one ends of the U-phase coils U1a, U1b, V-phase coils V1a, V1b, and W-phase coils W1a, W1b of the first system are connected to different phase bus bars 71, 72, 73, respectively. That is, the plurality of phase bus bars 71, 72, 73 are connected to lead wires 33a drawn out from the coils 33 of the respective phases. The other ends of the U-phase coils U1a and U1b, the V-phase coils V1a and V1b, and the W-phase coils W1a and W1b of the first system are connected to the neutral point bus bar 81 of the first system. That is, one first system neutral point bus bar 81 is connected to the lead wire 33a drawn out from the coil 33 of each phase. As a result, the U-phase coils U1a and U1b, the V-phase coils V1a and V1b, and the W-phase coils W1a and W1b of the first system form a Y connection.

The connection configuration of each phase coil 33 of the second system coil group 8 is the same as the connection configuration of each phase coil of the first system coil group 7 . That is, the U-phase coils U2a and U2b of the second system are connected to the U-phase bus bar 71B of the second system and the neutral point bus bar 82 of the second system. The V-phase coils V2a and V2b of the second system are connected to the V-phase bus bar 72B of the second system and the neutral point bus bar 82 of the second system. The W-phase coils W2a and W2b of the second system are connected to the W-phase bus bar 73B of the second system and the neutral point bus bar 82 of the second system. As a result, the U-phase coils U2a and U2b, the V-phase coils V2a and V2b, and the W-phase coils W2a and W2b of the second system form a Y connection.

According to this embodiment, the stator 30 has a plurality of coil groups (the first coil group 7 and the second coil group 8). In the stator 30, the coil groups 7 and 8 of different systems are arranged symmetrically around the central axis J. As shown in FIG. Thereby, the redundancy of the motor 1 can be ensured. That is, even if one of the coil groups 7 and 8 of the plurality of systems fails, the motor 1 can be driven smoothly by using the other coil groups.

[Busbar Unit] The busbar unit 60 is provided in the motor 1 . The busbar unit 60 is positioned between the stator 30 and the bearing holder 10 in the axial direction. That is, the busbar unit 60 is provided above the stator 30 and below the bearing holder 10 .

FIG. 5 is a perspective view of the busbar unit 60. FIG. 6 is an exploded perspective view of the busbar unit 60. FIG. FIG. 7 is a plan view of the busbar unit 60. FIG.

The busbar unit 60 includes a busbar holder 61, a pair of terminal supports (external connection terminal supports) 66, a first system phase busbar group 70A, a second system phase busbar group 70B, and a first system neutral point busbar. 81 and a second system neutral point bus bar 82 .

The first system phase bus bar group 70A and the first system neutral point bus bar 81 are connected to the first system coil group 7 . The second system phase bus bar group 70B and the second system neutral point bus bar 82 are connected to the second system coil group 8 .

The first system phase busbar group 70A and the second system phase busbar group 70B are fixed to one axial side (in this embodiment, the upper side) of the busbar holder 61, and the first system neutral point busbar 81 and the second system phase busbar group 70B The neutral point busbar 82 is fixed to the other axial side (lower side in the present embodiment) of the busbar holder 61 . In this specification, "one side" and "the other side" do not indicate a specific direction. That is, the above description can be rephrased as follows. The first system phase busbar 81 and the second system neutral point busbar 82 are fixed to one axial side of the busbar holder 61, and the first system phase busbar group 70A and the second system phase busbar group 70B are It is fixed to the other side of the busbar holder 61 in the axial direction.

The first system phase busbar group 70A has a U-phase busbar 71A, a V-phase busbar 72A, and a W-phase busbar 73A. Similarly, the second system phase busbar group 70B has a U-phase busbar 71B, a V-phase busbar 72B, and a W-phase busbar 73B.

In the following description, the U-phase busbars 71A and 71B of different systems are simply referred to as the U-phase busbar 71 when not distinguished from each other. Further, when the V-phase busbars 72A and 72B of different systems are not distinguished, they are simply referred to as the V-phase busbar 72 . When the W-phase busbars 73A and 73B of different systems are not distinguished, they are simply referred to as the W-phase busbar 73 . Further, the U-phase busbar 71, the V-phase busbar 72 and the W-phase busbar 73 are simply referred to as phase busbars 71, 72 and 73 when not distinguished from each other. Similarly, the first system neutral point busbar 81 and the second system neutral point busbar 82 are simply referred to as neutral point busbars 81 and 82 when not distinguished from each other.

The U-phase busbars 71A and 71B, the V-phase busbars 72A and 72B, and the W-phase busbars 73A and 73B are phase busbars (first busbars). That is, the plurality of phase bus bars 71, 72, and 73 are connected to U-phase coils U1a, U1b, U2a, and U2b, V-phase coils V1a, V1b, It includes phase bus bars connected to V2a, V2b and W-phase coils W1a, W1b, W2a, W2b, respectively.

(Busbar Holder) As shown in FIG. 1, the busbar holder 61 is provided above the stator 30 . Busbar holder 61 holds phase busbars 71 , 72 , 73 and neutral point busbars 81 , 82 . The busbar holder 61 is made of a resin material.

As shown in FIG. 6, the busbar holder 61 includes a holder main body (busbar holder main body) 62, a pair of base portions 63, a plurality of (six in this embodiment) clamping portions 64, and a plurality of (six in this embodiment) 6) legs 65.

The holder main body 62 has an annular shape centered on the central axis J when viewed from the axial direction. The holder main body 62 is positioned between the phase busbars 71, 72, 73 and the neutral point busbars 81, 82 in the axial direction. Further, the holder body portion 62 has an upper surface 62a facing upward and a lower surface 62b facing downward. A plurality of phase bus bars 71 , 72 , 73 are arranged on the upper surface 62 a of the holder body portion 62 . A plurality of neutral point bus bars 81 and 82 are arranged on the lower surface 62 b of the holder body portion 62 .

As shown in FIG. 1, the lower surface 62b of the holder body portion 62 is provided with a first wall portion 62c and a second wall portion 62d. That is, the busbar holder 61 has a first wall portion 62c and a second wall portion 62d. The first wall portion 62c and the second wall portion 62d axially protrude from the lower surface 62b. Further, the first wall portion 62c and the second wall portion 62d each extend along the circumferential direction. The first wall portion 62c is positioned radially outward with respect to the neutral point busbars 81 and 82 . The second wall portion 62d is positioned radially inward with respect to the neutral point bus bars 81,82. Therefore, the neutral point bus bars 81, 82 are located between the first wall portion 62c and the second wall portion 62d in the radial direction and extend along the circumferential direction.

A plurality of shaft portions 67a, 68a, 69a and a plurality of welding portions 67b, 68b, 69b located at the tips of the shaft portions 67a, 68a, 69a are provided on the lower surface 62b of the holder main body portion 62, respectively. That is, the busbar holder 61 has a plurality of shaft portions 67a, 68a, 69a and a plurality of welding portions 67b, 68b, 69b. As described below with reference to FIG. 10 , the plurality of welded portions 67 b , 68 b , 69 b fix the neutral point busbars 81 , 82 to the busbar holder 61 .

As shown in FIG. 6 , the base portion 63 protrudes upward from the upper surface 62 a of the holder body portion 62 . The pair of base portions 63 are located on opposite sides with the central axis J interposed therebetween. One of the pair of base portions 63 holds the external connection terminals 71c, 72c, 73c of the first system phase busbar group 70A, and the other holds the external connection terminals 71c, 72c of the second system phase busbar group 70B. , 73c.

The base portion 63 has an upper surface 63a facing upward. A terminal support 66 is mounted on the upper surface 63 a of the base portion 63 . The upper surface 63a is provided with four grooves (recesses) 63d. That is, the busbar holder 61 is provided with a concave groove 63d. A portion of the V-phase bus bar 72, a portion of the W-phase bus bar 73, and two U-phase bus bars 71 of different systems (a first U-phase bus bar 71A and a second A part of the system U-phase bus bar 71B) is inserted. Thereby, the base portion 63 holds the plurality of phase bus bars 71 , 72 , 73 .

As shown in FIG. 1, the upper surface 63a of the base portion 63 is provided with a shaft portion 63b extending upward and a welding portion 63c positioned at the upper end of the shaft portion 63b. That is, the busbar holder 61 has a shaft portion 63b and a welding portion 63c.

The shaft portion 63b passes through a fixing hole 66h provided in the terminal support 66. As shown in FIG. The welded portion 63c extends to the outside of the fixing hole 66h on the upper side of the fixing hole 66h of the terminal support 66 when viewed from the axial direction. The welded portion 63c has a hemispherical shape that protrudes upward. The welded portion 63c is formed by melting the upper end portion of the shaft portion 63b with heat. The welded portion 63c prevents the terminal support 66 from slipping out of the shaft portion 63b. The terminal support 66 is fixed to the busbar holder 61 by providing the welding portion 63c.

As shown in FIG. 7, the holding portion 64 is provided on the upper surface 62a of the holder body portion 62. As shown in FIG. The holding portion 64 has a pair of claw portions 64a extending upward from the upper surface 62a. The pair of claw portions 64a sandwich and hold the phase bus bars 71, 72, 73 from the thickness direction. That is, the holding portion 64 holds the plurality of phase bus bars 71, 72, 73 from the thickness direction. In the present embodiment, the holding portions 64 are provided in the same number (six) as the phase bus bars 71 , 72 , 73 provided on the upper side of the bus bar holder 61 . Therefore, one phase bus bar 71 , 72 , 73 is held by one holding portion 64 . Note that the number of holding portions 64 may be more than six.

A plurality of legs 65 (six in this embodiment) are provided on the busbar holder 61 . The plurality of legs 65 are arranged at equal intervals around the central axis. The busbar holder 61 is supported by the stator 30 at leg portions 65 .

As shown in FIG. 6, the leg portion 65 includes a radially extending portion 65a extending radially outward from the outer edge of the holder main body portion 62, and a lower side extending downward from the radially outer tip of the radially extending portion 65a. and an extension portion 65b. That is, the leg portion 65 extends downward with respect to the holder body portion 62 .

As shown in FIG. 9, the lower end portion 65c of the leg portion 65 has a V shape that narrows radially inward when viewed in the axial direction. As shown in FIG. 2 , the V-shaped lower end portion 65 c is accommodated in the leg accommodation portion 37 provided in the upper insulator 35 . Also, the leg portion 65 contacts the upper surface of the stator 30 at the lower end surface. As described above, the leg accommodation portion 37 has a V shape that is the same shape as or similar to the lower end portion 65c of the leg portion 65 when viewed from the axial direction. The leg portion 65 is housed in the leg portion housing portion 37 , so that the busbar holder 61 is positioned with respect to the stator 30 in a plane perpendicular to the axial direction.

The leg accommodation portion 37 is provided above the boundary portion between the core pieces 32 adjacent in the circumferential direction. The leg portion 65 accommodated in the leg portion accommodating portion 37 is provided above the boundary portion between the core pieces 32 adjacent in the circumferential direction. That is, the legs 65 are arranged so as to overlap the boundary between the core pieces 32 adjacent in the circumferential direction when viewed in the axial direction.

According to the present embodiment, the lower end portion 65c of the leg portion 65 and the leg portion accommodating portion 37 are formed in a V shape that tapers toward one side in the radial direction, so that the leg portion 65 relative to the leg portion accommodating portion 37 is formed in a V shape. can be easily inserted. In addition, each leg portion 65 contacts the V-shaped wall portion of the leg accommodation portion 37 when viewed from the axial direction facing one side and the other side in the circumferential direction. Therefore, the positioning accuracy of the busbar holder 61 in the circumferential direction can be improved. Note that the leg accommodation portion 37 may have a shape other than the V shape. For example, the same effect can be obtained even with a trapezoidal shape or a semicircular shape.

As shown in FIG. 2, a straight line connecting the lead wire 33a drawn from each coil 33 and the center axis J when viewed from the axial direction is assumed to be a virtual line VL. When viewed from the axial direction, the leg portion 65 is positioned between the imaginary lines VL of the lead wires 33a of the pair of coils 33 adjacent in the circumferential direction. The lead wire 33a is connected to any one of coil terminals 71a, 72a, 73a, 81a, and 82a provided to the plurality of phase busbars 71, 72, and 73 and the plurality of neutral point busbars 81 and 82, respectively. connected to

According to the present embodiment, the leg portion 65 is arranged between the pair of virtual lines VL arranged in the circumferential direction, so that the leg portion 65 and the coil terminals 71a, 72a, 73a, 81a, 82a can be shifted. Thereby, interference between the leg portion 65 and the coil terminals 71a, 72a, 73a, 81a, 82a and the lead wire 33a can be suppressed. In addition, the legs 65 are unlikely to interfere with the welding process between the coil terminals 71a, 72a, 73a, 81a, 82a and the lead wires 33a.

In this embodiment, the plurality of coil terminals 71a, 72a, 73a, 81a, 82a are alternately arranged along the circumferential direction at a first interval and a second interval narrower than the first interval. Therefore, the plurality of virtual lines VL extending radially from the central axis J alternately extend along the circumferential direction at a first angle α and a second angle β smaller than the first angle α. The leg portion 65 of this embodiment is positioned between a pair of virtual lines VL forming the first angle α. Regardless of whether the leg portion 65 is arranged between the pair of virtual lines VL forming the first angle α or between the pair of virtual lines VL forming the second angle β, the leg A certain effect of suppressing interference between the portion 65 and the lead wire 33a can be obtained. Further, as shown in the present embodiment, by arranging the leg portion 65 between a pair of virtual lines VL forming the first angle α, there is an effect of suppressing interference between the leg portion 65 and the lead line 33a. can be further increased.

When viewed from the axial direction, the leg portion 65 is positioned between a pair of coil terminals (for example, a pair of coil terminals 81a and 73a) connected to the lead wires 33a of a pair of coils 33 adjacent in the circumferential direction. . According to the present embodiment, even if the leg portion 65 and the coil terminals 81a and 73a are aligned in the radial direction, the leg portion 65 and the coil terminals 81a and 73a are displaced in the circumferential direction. Therefore, interference between the leg portion 65 and the coil terminals 81a and 73a can be suppressed.

According to the present embodiment, the arrangement described above suppresses interference between the leg portion 65 and the coil terminals 71a, 72a, 73a, 81a, and 82a. There is no need to displace 81a and 82a in the axial direction. More specifically, as shown in FIG. 5, a portion of the leg portion 65 can be arranged so as to axially overlap with a portion of the coil terminals 82a. By arranging at least a portion of the leg portion 65 so as to axially overlap the coil terminal 82a, the axial dimension of the busbar unit 60 can be reduced.

(Phase Busbar (First Busbar, Busbar)) A plurality of phase busbars 71 , 72 , 73 are fixed above the busbar holder 61 . The plurality of phase busbars 71, 72, 73 are classified into a first system phase busbar group 70A and a second system phase busbar group 70B. As described above, the first system phase busbar group 70A and the second system phase busbar group 70B have the U-phase busbar 71, the V-phase busbar 72, and the W-phase busbar 73, respectively.

The U-phase busbars 71 of the first system phase busbar group 70A and the second system phase busbar group 70B have the same shape. The V-phase busbars 72 have the same shape, and the W-phase busbars 73 of the first system phase busbar group 70A and the second system phase busbar group 70B have the same shape.

As shown in FIG. 6, the U-phase bus bar 71 has a bus bar body portion 71b, coil terminals 71a, external connection terminals 71c, and projecting portions 71e. Similarly, the V-phase bus bar 72 has a bus bar body portion 72b, coil terminals 72a, external connection terminals 72c, and projecting portions 72e. Further, the W-phase bus bar 73 has a bus bar body portion 73b, coil terminals 73a, external connection terminals 73c, and projecting portions 73e.

The busbar body portions 71b, 72b, 73b extend along planes perpendicular to the axial direction. The busbar main body portions 71b, 72b, 73b each extend along the circumferential direction. The busbar main body portions 71b, 72b, and 73b are arranged with the direction orthogonal to the axial direction as the thickness direction.

The coil terminals 71a, 72a, 73a are located at one ends of the busbar body portions 71b, 72b, 73b, respectively. The coil terminals 71a, 72a, 73a extend radially outward from the busbar body portions 71b, 72b, 73b. The coil terminals 71a, 72a, and 73a may extend radially inward with respect to the busbar body portions 71b, 72b, and 73b. That is, the coil terminals 71a, 72a, 73a need only extend radially to one side with respect to the busbar body portions 71b, 72b, 73b.

The coil terminals 71a, 72a, 73a are connected to the lead wire 33a. The coil terminals 71a, 72a, and 73a are portions that hold the lead wire 33a. Each of the coil terminals 71a, 72a, and 73a has a substantially U shape that opens radially inward when viewed from above. The coil terminals 71a, 72a, and 73a are arranged with the thickness direction perpendicular to the axial direction.

The external connection terminals 71c, 72c, and 73c are located at the ends (other ends) of the busbar main bodies 71b, 72b, and 73b opposite to the coil terminals 71a, 72a, and 73a, respectively. The external connection terminals 71c, 72c, 73c extend upward from the busbar body portions 71b, 72b, 73b.

The three external connection terminals 71c, 72c, and 73c are provided in the first system phase busbar group 70A and the second system phase busbar group 70B, respectively. The external connection terminals 71c, 72c, 73c of the first system phase busbar group 70A and the external connection terminals 71c, 72c, 73c of the second system phase busbar group 70B are arranged on opposite sides of the central axis J. .

The external connection terminals 71c, 72c, and 73c are arranged with the direction orthogonal to the axial direction as the thickness direction. Further, the external connection terminals 71c of the U-phase bus bar 71 are arranged with the direction perpendicular to the radial direction as the plate width direction. On the other hand, the external connection terminals 72c and 73c of the V-phase bus bar 72 and the W-phase bus bar 73 are arranged with the board width direction perpendicular to the board width direction of the external connection terminal 71c of the U-phase bus bar 71. FIG.

As shown in FIG. 6, the projecting portions 71e, 72e, 73e extend from the connection portions between the busbar main body portions 71b, 72b, 73b and the external connection terminals 71c, 72c, 73c to the opposite side of the busbar main body portion 71b. The protrusions 71e, 72e, and 73e are arranged with the direction orthogonal to the axial direction as the thickness direction.

The phase busbars 71, 72, and 73 are formed by recessed grooves ( recess) 63d. Therefore, the phase busbars 71, 72, 73 are held by the busbar holder 61 at the roots of the external connection terminals 71c, 72c, 73c. Therefore, the busbar holder 61 can stably support the stress received when the external connection terminals 71c, 72c, and 73c are inserted into the socket of the external device.

According to the present embodiment, the busbar main body portions 71b, 72b, 73b and the projecting portions 71e, 72e, 73e are located at the roots of the external connection terminals 71c, 72c, 73c in the plate width direction of the external connection terminals 71c, 72c, 73c. extending on both sides. The busbar body portions 71b, 72b, 73b and the projecting portions 71e, 72e, 73e suppress rattling of the external connection terminals 71c, 72c, 73c in the plate width direction inside the concave groove 63d. As a result, the stability of inserting the external connection terminals 71c, 72c, and 73c into the sockets of the external device can be enhanced.

In the phase busbars 71, 72, 73, the full width of the busbar body portions 71b, 72b, 73b and the full width of the projecting portions 71e, 72e, 73e overlap in the axial direction. Therefore, the stability of the external connection terminals 71c, 72c, and 73c can be enhanced, and the effect of suppressing rattling on both sides in the width direction of the external connection terminals 71c, 72c, and 73c can be enhanced.

As shown in FIG. 7, the U-phase bus bar 71 is the phase bus bar having the longest length along the circumferential direction of the bus bar body portion among the three types of phase bus bars 71, 72, and 73. As shown in FIG. The busbar main body portion 71b of the U-phase busbar 71 is located radially inside the busbar main body portions 72b and 73b of the other phase busbars (the V-phase busbar 72 and the W-phase busbar 73). More specifically, the busbar main body portion 71b of the U-phase busbar 71 is positioned radially inside the V-phase busbar 72 belonging to the same busbar group and the W-phase busbar 73 belonging to the other busbar group. do.

The phase busbars 71, 72, 73 of the present embodiment are radially overlapped in the busbar main body portions 71b, 72b, 73b. Therefore, by arranging the busbar main body portions 71b, 72b, 73b so that the thickness direction thereof is perpendicular to the axial direction, the phase busbars 71, 72, 73 can be arranged compactly in the radial direction. As a result, the radial dimension of the busbar unit 60 can be reduced.

According to the present embodiment, among the plurality of phase bus bars 71, 72, and 73, the U-phase bus bar 71 having the longest length along the circumferential direction of the bus bar body 71b is the other phase bus bar (that is, the V phase bus bar). It radially overlaps with at least part of the phase bus bar 72 and the W-phase bus bar 73). In addition, the busbar main body portion 71b of the U-phase busbar 71 is located on the side opposite to the direction in which the coil terminals 72a and 73a of the other phase busbars extend in the radial direction. Therefore, the busbar body portion 71b of the U-phase busbar 71 is sufficiently spaced radially from the lead wires 33a connected to the coil terminals 72a and 73a of the V-phase busbar 72 and the W-phase busbar 73. Can be placed apart. As a result, insulation can be ensured without separating the busbar body portion 71b of the U-phase busbar 71 and the lead wire 33a with a wall or the like.

In the present embodiment, the V-phase bus bar 72 and the W-phase bus bar 73 are held by the holding portion 64 in the radially extending regions of the coil terminals 72a and 73a. On the other hand, the U-phase busbar 71 is held by the sandwiching portion 64 in the busbar body portion 71b. The holding portion 64 that holds the U-phase busbar 71 does not radially overlap the V-phase busbar 72 and the W-phase busbar 73 in the radial direction. That is, of the plurality of phase bus bars 71, 72, and 73, the U-phase bus bar 71, which has the longest length along the circumferential direction of the bus bar main body 71b, is a region that does not radially overlap the other phase bus bars. The busbar body portion 71b is held by the clamping portion 64 . In other words, the busbar body portion 71b of the U-phase busbar 71 radially overlaps the V-phase busbar 72 and the W-phase busbar 73 in the region not held by the holding portion 64 . Therefore, the U-phase busbar 71, the V-phase busbar 72, and the W-phase busbar 73 can be arranged close to each other in the radial direction.

The busbar body portion 71b of the U-phase busbar 71 extends 180° around the central axis J along the circumferential direction. Therefore, the external connection terminal 71c located at one end of the busbar main body portion 71b and the coil terminal 71a located at the other end of the busbar main body portion 71b are arranged on opposite sides of the central axis J. As a result, the external connection terminals 71c, 72c, 73c of one system can be connected while reducing the circumferential dimension of the body portions 72b, 73b of the other phase busbars (the V-phase busbar 72 and the W-phase busbar 73). can be placed side by side. In this embodiment, the U-phase bus bar 71 is the phase bus bar having the longest length in the circumferential direction of the bus bar main body among the plurality of phase bus bars 71 , 72 , and 73 . However, if the busbar body portions 72b, 73b of the V-phase busbar 72 or the W-phase busbar 73 are longer than the busbar body portions of the other phase busbars, the busbar body portions 72b of these phase busbars 72, 73 , 73b extend around the central axis J by 180°.

In the present embodiment, the external connection terminals 71c, 72c, 73c of the phase bus bars 71, 72, 73 of the same phase and of different systems are located on opposite sides of the central axis J. That is, the external connection terminals 71c, 72c, 73c of the pair of phase bus bars 71, 72, 73 connected to the same phase coils 33 of the first system coil group 7 and the second system coil group 8 are connected to the center They are arranged on opposite sides of the axis J. Thereby, the three external connection terminals 71c, 72c, and 73c of the first system and the second system can be arranged symmetrically with the central axis J as the center. As a result, even if the circumferential position of the motor 1 is rotated by 180°, the motor 1 can be connected to the external device, and the process of connecting the motor 1 to the external device can be simplified.

When viewed from the axial direction, one external connection terminal 71c and the other coil terminal 71a of the first system U-phase bus bar 71A and the second system U-phase bus bar 71B are partially connected to each other. overlaps with A busbar body portion 71b of the U-phase busbar 71A has a crank portion 71d extending in the axial direction in the vicinity of the base of the external connection terminal 71c. By providing the crank portion 71d in the busbar main body portion 71b, the external connection terminal 71c is offset upward, and interference with the coil terminal 71a is suppressed.

As shown in FIG. 6, the busbar body portions 72b and 73b of the V-phase busbar 72 and the W-phase busbar 73 do not have a portion corresponding to the crank portion 71d of the U-phase busbar 71. As shown in FIG. Therefore, the busbar body portions 72b and 73b of the V-phase busbar 72 and the W-phase busbar 73 extend only within a plane perpendicular to the axial direction.

In the phase busbars 71, 72, 73, the busbar main bodies 71b, 72b, 73b and the coil terminals 71a, 72a, 73a are formed by bending a plate member extending in one direction. In the V-phase bus bar 72 and the W-phase bus bar 73, the full width of the bus bar main body portions 72b and 73b and the full width of the coil terminals 72a and 73a overlap in the axial direction. Therefore, when the V-phase bus bar 72 and the W-phase bus bar 73 are manufactured by press working, compared to the case where the coil terminals extend upward or downward with respect to the bus bar main body, the V-phase It is possible to increase the number of the busbars 72 for the W-phase and the number of the busbars 73 for the W-phase.

(Terminal Support (External Connection Terminal Support)) The terminal support 66 is fixed to the upper side of the busbar holder 61 . The terminal support 66 covers the upper surface 63 a of the base portion 63 of the busbar holder 61 . The terminal support 66 is made of a resin material.

The terminal support 66 has a terminal support body portion 66a, three support portions 66b extending upward from the terminal support body portion 66a in a columnar shape, and a convex portion 66d projecting downward from the terminal support body portion 66a. The support portion 66b has a cylindrical shape. The three support portions 66b are arranged along the circumferential direction.

As shown in FIG. 1, the terminal support body portion 66a is provided with a fixing hole 66h penetrating in the axial direction. The shaft portion 63b of the busbar holder 61 is inserted into the fixing hole 66h.

Each of the three support portions 66b is provided with a holding hole 66c penetrating therethrough in the axial direction. That is, the terminal support 66 is provided with three holding holes 66c. External connection terminals 71c, 72c, and 73c of the U-phase bus bar 71, the V-phase bus bar 72, and the W-phase bus bar 73 are inserted into the three holding holes 66c, respectively. Thereby, the three holding holes 66c hold the external connection terminals 71c, 72c, and 73c.

The external connection terminals 71c, 72c, and 73c are inserted from below the holding holes 66c and protrude above the support portion 66b. The external connection terminals 71c, 72c, and 73c pass through the through holes 16a of the bearing holder 10 in the area surrounded by the support portion 66b.

According to this embodiment, the external connection terminals 71 c , 72 c , 73 c are held by the holding holes 66 c of the terminal support 66 . This can improve the stability of the external connection terminals 71c, 72c, and 73c when they are inserted into the sockets of the external devices.

According to this embodiment, the external connection terminals 71 c , 72 c , 73 c are surrounded by the support portion 66 b of the terminal support 66 . Therefore, when the busbar unit 60 is arranged below the bearing holder 10 and the external connection terminals 71c, 72c, 73c are inserted into the through holes 16a of the bearing holder 10, the external connection terminals 71c, 72c, 73c and the through holes 16a A support portion 66b can be interposed between the inner peripheral surface of the As a result, insulation between the external connection terminals 71c, 72c, 73c and the bearing holder 10 can be ensured.

As shown in FIG. 6, the convex portion 66d extends like a plate downward from the terminal support body portion 66a. The convex portion 66 d fits into the concave groove 63 d of the busbar holder 61 . Thereby, the reliability of holding the terminal support 66 by the busbar holder 61 can be enhanced. Moreover, as a result, the reliability of holding the external connection terminals 71c, 72c, and 73c held by the terminal support 66 can be enhanced.

As described above, the busbar body portions 71b, 72b, 73b of the phase busbars 71, 72, 73 are inserted into the grooves 63d. The convex portion 66d fits into the concave groove 63d from the upper side of the busbar body portions 71b, 72b, 73b. As a result, the phase bus bars 71, 72, 73 are held from above in the concave grooves 63d, so that the phase bus bars 71, 72, 73 can be stably held in the bus bar unit 60. FIG.

Of the three projections 66d, the two projections 66d that hold down the busbar body portions 72b and 73b of the V-phase busbar 72 and the W-phase busbar 73 extend downward along the external connection terminals 72c and 73c, respectively. It extends and fits into the concave groove 63d. Therefore, these two protrusions 66d can press the vicinity of the roots of the external connection terminals 72c and 73c from above, thereby increasing the effect of stabilizing the external connection terminals 72c and 73c.

FIG. 8 is a cross-sectional view taken along line VIII--VIII of FIG. FIG. 8 illustrates the fixing structure of the V-phase bus bar 72 inserted into the concave groove 63d. Although the description is omitted here, a similar fixing structure is adopted for the U-phase bus bar 71 and the W-phase bus bar 73 that are inserted into the other grooves 63d.

The upper opening of the groove 63d is provided with a tapered portion 63e whose groove width increases toward the upper side. The provision of the tapered portion 63e facilitates the step of inserting the phase bus bar 72 and the convex portion 66d into the concave groove 63d.

A tip surface 66f of the convex portion 66d contacts the surface of the phase bus bar 72 facing upward. A welded portion 66e that joins to the inner surface of the concave groove 63d is provided at the tip of the convex portion 66d. The welded portion 66e is formed by melting and solidifying the tip of the convex portion 66d. The welded portion 66e is joined to the wall surface of the recessed groove 63d and the companion bus bar 72 during the solidification process. Thereby, the terminal support 66 can be firmly fixed to the busbar holder 61 . In addition, it is possible to effectively prevent the phase bus bar 72 from slipping out of the concave groove 63d. In this embodiment, the case where the welded portion 66e is provided at the tip portion of the convex portion 66d is exemplified. In addition, it is sufficient if the welded portion 66e is provided on at least a part of the convex portion 66d.

The terminal support 66 is made of a resin material including a first resin portion 66A and a second resin portion 66B integrally molded. That is, the terminal support 66 is formed by two-color molding. That is, the terminal support 66 is molded by two-color molding of the first resin portion 66A and the second resin portion 66B.

The second resin portion 66B is a thermoplastic resin material having a melting point lower than that of the first resin portion 66A. The terminal support body portion 66a and the support portion 66b are composed of the first resin portion 66A. On the other hand, the convex portion 66d is composed of the second resin portion 66B.

According to this embodiment, the welded portion 66e is composed of the second resin portion 66B having a low melting point. Therefore, the welding part 66e can be easily formed by heating the terminal support 66 with the convex part 66d inserted into the concave groove 63d. In addition, in this embodiment, the case where the whole convex part 66d is comprised from the 2nd resin part 66B was illustrated. However, it is sufficient that a part of the portion of the convex portion 66d that fits into the concave groove 63d is composed of the second resin portion 66B.

A procedure for fixing the terminal support 66 to the busbar holder 61 in the method of manufacturing the busbar unit 60 will be described. First, a busbar mounting process for mounting the phase busbars 71 , 72 , 73 to the busbar holder 61 is performed. In the step of attaching the phase busbars, the phase busbars 71 , 72 , 73 are inserted into the concave grooves 63 d provided in the busbar holder 61 .

Next, a terminal support mounting step (external connection terminal support mounting step) for mounting the terminal support 66 on the busbar holder 61 is performed. In the terminal support mounting process, first, the external connection terminals 71 c , 72 c , and 73 c are inserted into the holding holes 66 c of the terminal support 66 . Next, the convex portion 66d of the terminal support 66 is fitted into the concave groove 63d from above the phase busbars 71, 72, 73. As shown in FIG. Further, heat is applied to the terminal support 66 to partially melt and further solidify the convex portion 66d, thereby forming a welding portion 66e to be joined to the inner surface of the concave groove 63d.

In the procedure for forming the welded portion 66e, current may be applied to the phase bus bars 71, 72, 73 to partially melt the convex portion 66d. By applying current to the phase bus bars 71, 72, 73, the phase bus bars 71, 72, 73 generate heat due to Joule heat. This heat is transmitted to the convex portion 66d and partially melts the convex portion 66d. When forming the welding portion 66e by applying current to the phase bus bars 71, 72, 73, only the tip portion of the convex portion 66d can be locally heated. Therefore, the welded portion 66 e can be formed without affecting other portions of the terminal support 66 . Note that the current value to be supplied to the phase bus bars 71, 72, and 73 when forming the welded portion 66e by Joule heat is sufficiently larger than the current value when the motor 1 is driven.

(Neutral Point Busbar (Second Busbar, Busbar)) As described above, the stator 30 of the present embodiment has two coil groups 7 and 8 (see FIG. 4). A plurality of neutral point bus bars 81 and 82 are provided in the same number as the number of coil groups (that is, the number of systems). Therefore, the busbar unit 60 of this embodiment has two neutral point busbars 81 and 82 .

9 is a bottom view of the busbar unit 60. FIG. As shown in FIG. 9, the neutral point busbars 81 and 82 have busbar body portions 81b and 82b and three coil terminals 81a and 82a. Neutral point bus bars 81 and 82 are plate-shaped. In the neutral point busbars 81 and 82, at least the busbar body portions 81b and 82b are arranged with the axial direction as the thickness direction.

The busbar body portions 81b, 82b extend along planes perpendicular to the axial direction. The busbar body portions 81b and 82b each extend in the circumferential direction in a 240° region around the central axis J. As shown in FIG. At least a portion of the busbar main body portions 81 b and 82 b is exposed from the busbar holder 61 . That is, the neutral point busbars 81 and 82 are not resin insert-molded in the busbar holder 61 .

The coil terminals 81a and 82a are connected to the lead wire 33a. The coil terminals 81a and 82a include portions for gripping the lead wire 33a. Each of the coil terminals 81a and 82a has a substantially U shape opening radially inward when viewed from above. The coil terminals 81a and 82a are arranged with the thickness direction perpendicular to the axial direction.

The three coil terminals 81a and 82a are arranged at equal intervals along the length direction (that is, the circumferential direction) of the busbar body portions 81b and 82b, respectively. Of the three coil terminals 81a and 82a, two coil terminals 81a and 82a are located at both ends of the busbar main body portions 81b and 82b, and the remaining one coil terminal 81a and 82a is the two coil terminals described above. It is located between 81a and 82a.

The coil terminals 81a, 82a extend radially away from the busbar body portions 81b, 82b. More specifically, the coil terminals 81a, 82a extend radially outward from the busbar body portions 81b, 82b.

Note that the coil terminals 81a and 82a may extend radially inward with respect to the busbar body portions 81b and 82b. In other words, the coil terminals 81a and 82a may extend radially to one side with respect to the busbar body portions 81b and 82b.

The coil terminals 81a, 82a of the neutral point busbars 81, 82 and the coil terminals 71a, 72a, 73a of the phase busbars 71, 72, 73 are connected to the respective busbar main bodies 81b, 82b, 71b, 72b, 73b. It extends in the same radial direction. By arranging in this way, the coil terminals 81a, 82a, 71a, 72a, 73a of the neutral point busbars 81, 82 and the phase busbars 71, 72, 73 protrude with respect to the busbar holder 61 in the radial direction. can be oriented. Therefore, the radial positions of the lead wires 33a extending from the stator 30 and connected to the coil terminals 81a, 82a, 71a, 72a, and 73a can be aligned. As a result, the structure of the busbar holder 61 for insulating the neutral point busbars 81, 82 and the phase busbars 71, 72, 73 from the lead wire 33a (eg, the first wall portion 62c in the present embodiment) is less complicated. . In addition, by arranging in this way, when viewed from the axial direction, the coil terminals 71a, 72a, 73a of the plurality of phase busbars 71, 72, 73 and the coil terminals 81a of the plurality of neutral point busbars 81, 82 , 82a line up on a single imaginary circle VC around the central axis J. FIG. Therefore, in the welding process, by rotating the busbar unit 60 and the stator 30 around the central axis J, the lead wires 33a and the coil terminals 81a, 82a, 71a, 72a, 72a, 81a, 81a, 72a, 81a, 81a, 81a, 81a, 81a, 81a, 81a, 81a, 81a, 81a, 81a, 81a can 73a can be welded together. This simplifies the welding process.

The coil terminals 81a, 82a extend downward from the busbar body portions 81b, 82b. That is, the coil terminals 81a, 82a extend away from the phase bus bars 71, 72, 73 in the axial direction. As a result, the coil terminals 81a, 82a can be arranged apart from the coil terminals 71a, 72a, 73a of the phase bus bars 71, 72, 73 in the axial direction, and mutual interference can be suppressed. In addition, in the welding process between the coil terminals of one of the neutral point bus bars 81, 82 and the phase bus bars 71, 72, 73 and the lead wire 33a, the welding workability of the other coil terminal deteriorates. can be suppressed.

The plurality of neutral point busbars 81 and 82 are classified into a first system neutral point busbar 81 and a second system neutral point busbar 82 . The first system neutral point bus bar 81 is connected to the lead wires 33a of the coils 33 of each phase (U phase, V phase, W phase) of one system coil group (first system coil group 7). Similarly, the second system neutral point bus bar 82 is connected to the lead wires 33a of the coils 33 of each phase (U phase, V phase, W phase) of one system coil group (second system coil group 8). be done. The coil terminals 71a, 72a, 73a of the phase busbars 71, 72, 73 and the coil terminals 81a, 82a of the neutral busbars 81, 82 are arranged alternately along the circumferential direction.

As shown in FIG. 6 , the multiple neutral point busbars 81 and 82 are fixed to the lower side of the busbar holder 61 . At least a portion of the plurality of neutral point bus bars 81 and 82 overlap each other when viewed in the axial direction.

The plurality of neutral point busbars 81 and 82 are plate members in which at least the busbar body portions 81b and 82b are arranged with the axial direction as the thickness direction. That is, the neutral point bus bars 81 and 82 of this embodiment are of the so-called flat type. Therefore, even when a plurality of neutral point bus bars 81 and 82 are stacked in the axial direction, the dimension in the axial direction is unlikely to increase.

According to the present embodiment, of the phase bus bars 71, 72, 73 and the neutral point bus bars 81, 82, the neutral point bus bars 81, 82 are of the flat type. On the other hand, the phase busbars 71, 72, 73 are of a so-called vertical type in which the busbar main bodies 71b, 72b, 73b are arranged with the axial direction as the thickness direction. Generally, at least three phase bus bars 71 , 72 , 73 are required corresponding to the U-phase, V-phase, and W-phase coils 33 . Therefore, when the phase busbars 71, 72, and 73 are of the flat type and stacked in the axial direction, it is necessary to stack three or more layers corresponding to each phase busbar. Also, an insulating layer is provided between the stacked busbars. Therefore, when it is necessary to stack three or more layers, the dimension in the axial direction is the sum of the plate thickness of the three bus bars and the thickness of the insulating layer therebetween. The effect of miniaturization in the axial direction is reduced. According to the present embodiment, by laminating two systems of neutral point bus bars 81 and 82 as a flat type, it is possible to enhance the effect of reducing the dimension in the axial direction. In this embodiment, the insulating layer provided between the axially overlapping busbars is an air layer.

As shown in FIG. 9, the plurality of neutral point bus bars 81, 82 are arranged between a first wall portion 62c and a second wall portion 62d provided in the holder main body portion 62, and extend in the circumferential direction. extend along. The first wall portion 62c and the second wall portion 62d are arranged to sandwich the busbar body portions 81b, 82b of the neutral point busbars 81, 82 in the radial direction.

According to the present embodiment, the first wall portion 62c is positioned between the busbar body portions 81b, 82b of the neutral point busbars 81, 82 and the lead wire 33a when viewed from the axial direction. This makes it possible to easily insulate the neutral point bus bars 81 and 82 from the lead wire 33a.

According to this embodiment, the neutral point bus bars 81 and 82 are sandwiched between the first wall portion 62c and the second wall portion 62d from the inside and outside in the radial direction. Therefore, the neutral point bus bars 81 and 82 can be easily positioned in the radial direction.

According to the present embodiment, the rigidity of the holder body portion 62 can be increased by providing the first wall portion 62c and the second wall portion 62d to the holder body portion 62 .

The first wall portion 62c is provided with a first notch portion 62ca and a second notch portion 62cb. Further, only the second notch portion 62db is provided in the second wall portion 62d. The neutral point bus bars 81, 82 are radially exposed at the first notch 62ca or the second notch 62cb, 62db.

The coil terminals 81a, 82a of the neutral point bus bars 81, 82 pass through the first notch 62ca. By providing the first notch portion 62ca, a structure in which the coil terminals 81a and 82a are directly extended radially outward from the busbar main body portions 81b and 82b can be adopted. In other words, the coil terminals 81a and 82a do not need to have portions extending downward to climb over the first wall portion 62c, and the neutral point bus bars 81 and 82 can be manufactured at low cost.

The second notch portions 62cb and 62db radially overlap wide portions 81s and 82s of neutral point bus bars 81 and 82, which will be described later. By providing the second notch portions 62cb and 62db, it is possible to prevent the wide portions 81s and 82s from interfering with the busbar holder 61 .

In this embodiment, some of the second cutouts 62cb allow the coil terminals 81a to pass therethrough. That is, some of the second cutouts 62cb also function as cutouts for allowing the coil terminals 81a to pass therethrough.

Of the plurality of second cutouts 62cb provided in the first wall portion 62c, at least some of the second cutouts 62cb are arranged radially out of alignment with the lead wire 33a. By arranging the second notch 62cb radially out of alignment with the lead wire 33a, it is easy to ensure insulation between the busbar body portions 81b and 82b exposed from the second notch 62cb and the lead wire 33a. Note that all the second cutouts 62cb may be arranged radially out of alignment with the lead wires 33a.

In the following description, one of the plurality of neutral point bus bars 81 and 82 located on the holder main body 62 side (that is, on the bus bar holder 61 side) is referred to as a first layer bus bar 81 . The other one of the plurality of neutral point busbars 81 and 82 located outside the first layer busbar 81 with respect to the holder main body 62 (busbar holder 61 side) is referred to as a second layer busbar 82 . Also, in the following description, the first layer bus bar 81 and the second layer bus bar 82 are collectively referred to as neutral point bus bars 81 and 82 . A first layer bus bar 81 is a first system neutral point bus bar 81 connected to the first system coil group 7 , and a second layer bus bar 82 connected to the second system coil group 8 is a second system neutral point bus bar 81 . It is the neutral point bus bar 82 .

10 is a schematic cross-sectional view taken along line XX of FIG. 9. FIG. A busbar main body portion 81b of the first layer busbar 81 is provided with a fixing hole (through hole) 81h and a passage hole (through hole) 81i penetrating in the axial direction. A busbar main body portion 82b of the second layer busbar 82 is provided with a fixing hole (through hole) 82h and a retraction hole (through hole) 82i penetrating in the axial direction.

In the present embodiment, the fixing holes 81h and 82h, the passage hole 81i and the retraction hole 82i are surrounded from all sides by the busbar body portions 81b and 82b. However, the fixing holes 81h, 82h, the passage hole 81i, and the retraction hole 82i may be notch-shaped as long as they penetrate in the axial direction. That is, the fixing holes 81h, 82h, the passage hole 81i, and the retraction hole 82i need only be surrounded from three sides by the busbar body portions 81b, 82b, and the entire interior region is surrounded by the busbar body portions 81b, 82b. It doesn't have to be.

A plurality of shaft portions 67a, 68a, 69a and a plurality of welding portions 67b, 68b, 69b located at the tips of the shaft portions 67a, 68a, 69a are provided on the lower surface 62b of the holder main body portion 62, respectively. The welded portions 67b, 68b, and 69b are hemispherical and convex downward. The welded portions 67b, 68b, 69b are formed by melting the tip portions of the shaft portions 67a, 68a, 69a with heat.

As shown in FIG. 9, the plurality of shaft portions 67a, 68a, 69a includes three first shaft portions 67a, two second shaft portions 68a, and one third shaft portion 69a. The plurality of welding portions 67b, 68b, and 69b includes a first welding portion 67b positioned at the tip of the first shaft portion 67a, a second welding portion 68b positioned at the tip of the second shaft portion 68a, and a third shaft portion 68b. and a third welding portion 69b located at the tip of the portion 69a.

The first shaft portion 67 a and the first welding portion 67 b are provided to fix the first layer bus bar 81 . The second shaft portion 68 a , the third shaft portion 69 a , the second welding portion 68 b and the third welding portion 69 b are provided for fixing the second layer bus bar 82 . Therefore, first layer bus bar 81 and second layer bus bar 82 are each fixed by three welded portions.

The first welded portion 67b, the second welded portion 68b, and the third welded portion 69b are arranged on a single imaginary circle around the central axis J. As shown in FIG. Therefore, in the heat crimping process for forming the first welded portion 67b, the second welded portion 68b, and the third welded portion 69b, by rotating the busbar unit 60 around the central axis J, the heat crimping jig is moved radially. No need to move. This simplifies the heat crimping process. In FIG. 9, illustration of a virtual circle in which the first welded portion 67b, the second welded portion 68b, and the third welded portion 69b are arranged is omitted. This virtual circle is a circle containing the arc-shaped line XX shown in FIG.

As shown in FIG. 10, the first shaft portion 67a passes through the fixing hole 81h of the first layer bus bar 81. As shown in FIG. The first welded portion 67 b is positioned below the first layer bus bar 81 . The first welded portion 67b extends to the outside of the fixing hole 81h of the first layer bus bar 81 when viewed in the axial direction. The first welding portion 67b has a first fixing surface 67d facing upward in a portion extending outward from the first shaft portion 67a. The first fixing surface 67 d contacts the bottom surface 81 p of the first layer bus bar 81 . In addition, the upper surface 81q of the first layer bus bar 81 contacts the lower surface 62b of the holder body portion 62. As shown in FIG. That is, the first layer bus bar 81 is sandwiched between the holder body portion 62 and the first welding portion 67b. Thereby, the first welding portion 67 b fixes the first layer bus bar 81 .

The retraction hole 82i of the second layer bus bar 82 is located in the region where the first layer bus bar 81 and the second layer bus bar 82 overlap when viewed in the axial direction, and is located below the first welding portion 67b fixing the first layer bus bar 81. Located in That is, the retraction hole 82i overlaps the first welded portion 67b when viewed from the axial direction. As shown in FIG. 9, the first welded portion 67b is located inside the inner peripheral surface of the evacuation hole 82i when viewed in the axial direction. That is, the first welded portion 67b is arranged in the hole of the retraction hole 82i when viewed from the axial direction.

According to the present embodiment, since the second layer bus bar 82 is provided with the retraction hole 82i, when the first layer bus bar 81 is fixed in the region where the first layer bus bar 81 and the second layer bus bar 82 overlap, Interference between the first welded portion 67b and the second layer bus bar 82 can be suppressed even if the first layer bus bar 81 and the second layer bus bar 82 are arranged close to each other in the axial direction.

That is, according to this embodiment, the first layer bus bar 81 can be fixed in the region where the first layer bus bar 81 and the second layer bus bar 82 overlap. Therefore, the welding portions 67b for fixing the first layer busbar 81 can be arranged in a well-balanced manner in the longitudinal direction of the busbar main body portion 81b of the first layer busbar 81 . In addition, since the first layer bus bar 81 and the second layer bus bar 82 can be arranged close to each other, the size of the bus bar unit 60 can be reduced in the axial direction.

As shown in FIG. 10, the second shaft portion 68a is provided with a stepped surface 68c facing the opposite side of the holder main body portion 62 (that is, the opposite side of the busbar holder 61, the lower side). The diameter of the second shaft portion 68a on the base end side (upper side) of the stepped surface 68c is larger than the diameter of the tip side (lower side) of the stepped surface 68c.

The second shaft portion 68 a passes through the passage hole 81 i of the first layer bus bar 81 and the fixing hole 82 h of the second layer bus bar 82 . The lower surface 81p of the first layer bus bar 81 is located above the stepped surface 68c. Therefore, the passage hole 81i of the first layer bus bar 81 is inserted through the second shaft portion 68a on the base end side of the stepped surface 68c.

On the other hand, the second layer bus bar 82 is positioned below the step surface 68c. The upper surface 82q of the second layer bus bar 82 contacts the stepped surface 68c. Therefore, the fixing hole 82h of the second layer bus bar 82 is inserted through the second shaft portion 68a on the distal end side of the stepped surface 68c.

The second welded portion 68 b is positioned below the second layer bus bar 82 . The second welded portion 68b extends to the outside of the fixing hole 82h of the second layer bus bar 82 when viewed in the axial direction. The second welded portion 68b has a second fixing surface 68d facing upward in a portion that spreads outward with respect to the second shaft portion 68a. The second fixing surface 68 d contacts the bottom surface 82 p of the second layer bus bar 82 . Since the upper surface 82q of the second layer bus bar 82 contacts the step surface 68c, the second layer bus bar 82 is sandwiched between the step surface 68c and the second welding portion 68b. Thereby, the second welded portion 68 b fixes the second layer bus bar 82 .

According to this embodiment, the second layer bus bar 82 can be fixed in the region where the first layer bus bar 81 and the second layer bus bar 82 overlap. Further, since the second shaft portion 68a passes through the passage hole 81i of the first layer bus bar 81, the first layer bus bar 81 can be positioned within a plane perpendicular to the axial direction. At least part of the outer peripheral surface of the second shaft portion 68a may be in contact with the inner peripheral surface of the passage hole 81i in a region on the base end side (upper side) of the stepped surface 68c. In this case, the positioning accuracy of the first layer bus bar 81 by the second shaft portion 68a can be improved.

As shown in FIG. 10, a lower surface 62b of the holder main body 62 is provided with a stepped portion 62e protruding downward. The stepped portion 62e has a stepped portion lower surface 62f facing downward. The third shaft portion 69a protrudes downward from the step portion lower surface 62f. The stepped portion lower surface 62f is arranged in a region of the lower surface 62b of the holder main body portion 62 where only the second layer bus bar 82 is provided. The upper surface 82q of the second layer bus bar 82 contacts the lower surface 62f of the step portion.

The third shaft portion 69a passes through the fixing hole 82h of the second layer busbar 82 in a region where the first layer busbar 81 and the second layer busbar 82 do not overlap. The third welded portion 69 b is positioned below the second layer bus bar 82 . The third welded portion 69b extends to the outside of the fixing hole 82h of the second layer bus bar 82 when viewed in the axial direction. The third welded portion 69b has a third fixing surface 69d facing upward at a portion that spreads outward with respect to the third shaft portion 69a. The third fixing surface 69 d contacts the bottom surface 82 p of the second layer bus bar 82 . That is, the second layer bus bar 82 is sandwiched between the stepped portion 62e of the holder body portion 62 and the third welding portion 69b. Thereby, the third welded portion 69b fixes the second layer bus bar 82 .

An insulating sheet (insulating member) 4 may be sandwiched between the first layer bus bar 81 and the second layer bus bar 82, as indicated by a phantom line (double-dot chain line) in FIG. That is, the busbar unit 60 may have the insulating sheet 4 interposed between the multiple neutral point busbars 81 and 82 . The insulating sheet 4 is provided with a hole portion 4h for avoiding interference with the first welding portion 67b and the second shaft portion 68a. By providing the insulating sheet 4 between the first layer bus bar 81 and the second layer bus bar 82, the reliability of the insulation between the first layer bus bar 81 and the second layer bus bar 82 can be enhanced.

In FIG. 9, the phase busbars 71, 72, 73 arranged above the busbar holder 61 are shown as hidden lines (broken lines). As shown in FIG. 9, the neutral point bus bars 81, 82 and the phase bus bars 71, 72, 73 at least partially overlap each other when viewed in the axial direction. As a result, the size of the busbar unit 60 can be reduced in the radial direction. A holder main body 62 of the busbar holder 61 is interposed between the phase busbars 71 , 72 , 73 and the neutral point busbars 81 , 82 in the axial direction. As a result, even when the phase busbars 71, 72, 73 and the neutral point busbars 81, 82 are overlapped with each other when viewed in the axial direction, the phase busbars 71, 72, 73 and the neutral point busbar 81 , 82 is easily ensured.

The welded portions 67b, 68b, 69b are arranged to be displaced from the phase bus bars 71, 72, 73 when viewed in the axial direction. As described above, the welding portions 67b, 68b, 69b are formed by melting the resin at the tips of the shaft portions 67a, 68a, 69a. Therefore, heat is applied to the busbar holder 61 to form the welded portions 67b, 68b, 69b. A portion of the holder main body 62 that overlaps with the welded portions 67b, 68b, 69b when viewed in the axial direction may be slightly deformed by heat during molding of the welded portions 67b, 68b, 69b. By arranging the welded portions 67b, 68b, and 69b so as to be offset from the phase busbars 71, 72, and 73 when viewed from the axial direction, the deformation when the welded portions 67b, 68b, and 69b are melted is the phase busbars 71 and 69b. It is possible to suppress the influence on the positional accuracy of 72 and 73 . Thereby, the positional accuracy of the phase bus bars 71, 72, 73 can be improved.

In the present embodiment, of the plurality of phase bus bars 71, 72, and 73, the U-phase bus bar 71, which has the longest length along the circumferential direction of the bus bar main bodies 71b, 72b, and 73b, has a diameter greater than that of the welded portions 67b and 68b. Pass the direction inside. U-phase bus bar 71 extends radially inward from welded portions 67b and 68b and extends along the circumferential direction, so that U-phase bus bar 71 can be shortened. As a result, the weight of the motor 1 can be reduced, and the material cost of the U-phase bus bar 71 can be saved.

In the present embodiment, the plurality of phase busbars 71, 72, 73 are plate-shaped, and are of a vertical type in which the busbar main bodies 71b, 72b, 73b are arranged with the direction orthogonal to the axial direction as the thickness direction. . When the phase bus bars 71, 72, 73 are of the vertical type, the phase bus bars 71, 72, 73 and the welding portions 67b, 68b, 69b are arranged so as not to overlap when viewed from the axial direction. However, the radial dimension of the busbar unit 60 is less likely to increase.

In the present embodiment, one welded portion 67b of the six welded portions 67b, 68b, 69b is located at the base of the coil terminal 81a of the first layer bus bar 81. As shown in FIG. That is, one welded portion 67b radially overlaps with the coil terminal 81a. By arranging in this way, it is easy to secure the positional accuracy of the coil terminal 81a and suppress the vibration of the coil terminal 81a. In this embodiment, the case where only one welded portion 67b is located at the base of the coil terminal 81a has been described. However, all the welded parts 67b, 68b, 69b may be positioned at the base of the coil terminal 81a.

The busbar body portion 81b of the first layer busbar 81 has a wide portion 81s provided around the passage hole 81i. Similarly, the busbar body portion 82b of the second layer busbar 82 has a wide portion 82s provided around the retraction hole 82i. The wide portions 81s and 82s extend outward in the width direction in a circular shape whose center coincides with the center of the passage hole 81i or the retraction hole 82i.

According to the present embodiment, by providing the wide portions 81s and 82s, the cross-sectional areas of the busbar main body portions 81b and 82b are reduced even if the neutral point busbars 81 and 82 are provided with the passage hole 81i or the retraction hole 82i. never An increase in electrical resistance of the neutral point bus bars 81 and 82 can be suppressed.

In the present embodiment, the stator 30 has two coil groups (the first coil group 7 and the second coil group 8), and the busbar unit 60 includes 6 coils corresponding to the phases of the two systems. The motor 1 having the two phase busbars 71, 72, 73 and the two neutral point busbars 81, 82 corresponding to the two systems has been described. However, the number of systems is not limited. For example, the stator 30 may have only three or more coil groups, and the busbar unit 60 may have three or more phase busbars and neutral point busbars corresponding to the coil groups.

Next, an embodiment of a device equipped with the motor 1 of this embodiment will be described. FIG. 11 is a schematic diagram of an electric power steering device equipped with the motor 1 of this embodiment. The electric power steering device 2 is mounted on a steering mechanism for wheels of an automobile. The electric power steering device 2 is a device that reduces steering force by hydraulic pressure. The electric power steering device 2 includes a motor 1 , a steering shaft 214 , an oil pump 216 and a control valve 217 .

Steering shaft 214 transmits input from steering 211 to axle 213 having wheels 212 . The oil pump 216 generates hydraulic pressure in the power cylinder 215 that transmits hydraulic driving force to the axle 213 . A control valve 217 controls the oil in the oil pump 216 . In the electric power steering device 2 , the motor 1 is mounted as a drive source for the oil pump 216 . It should be noted that the motor 1 of the present embodiment is not limited to the electric power steering device, and may be mounted on any device.

The embodiments and modifications of the present invention have been described above, but each configuration and combination thereof in the embodiments and modifications are examples, and additions and omissions of configurations may be made without departing from the scope of the present invention. , substitutions and other modifications are possible. Moreover, the present invention is not limited by the embodiments.

Claims (10)

a rotor that rotates around a vertically extending central axis;
a stator radially opposed to the rotor with a gap therebetween;
a busbar unit provided above the stator,
The stator has a plurality of systems of the coil groups, with a U-phase coil, a V-phase coil, and a W-phase coil as one system of coil groups,
The coil groups of different systems are arranged symmetrically about the central axis,
The busbar unit is
a plurality of phase bus bars each connected to a lead wire drawn out from each phase coil;
a busbar holder that holds the plurality of phase busbars,
The phase bus bar is
a busbar main body portion extending along the circumferential direction;
a coil terminal positioned at one end of the busbar main body portion, extending in one radial direction with respect to the busbar main body portion, and connected to the lead wire;
an external connection terminal positioned at the other end of the busbar main body portion and extending upward;
The phase bus bar is plate-shaped, and at least the bus bar main body portion is arranged with the direction orthogonal to the axial direction as the thickness direction,
Of the plurality of phase bus bars, the phase bus bar having the longest length along the circumferential direction of the bus bar main body radially overlaps at least a portion of the other phase bus bars, passes through the side opposite to the direction in which the coil terminal of the phase bus bar extends ,
The busbar holder has a clamping portion that holds the plurality of phase busbars in a thickness direction,
Among the plurality of phase bus bars, the phase bus bar having the longest length along the circumferential direction of the bus bar main body portion is located in a region that does not radially overlap the other phase bus bars, and the bus bar main body portion A motor held in a clamp . The stator has two coil groups classified into a first coil group and a second coil group,
2. The phase bus bars of claim 1, wherein the plurality of phase bus bars include phase bus bars connected to U-phase coils, V-phase coils, and W-phase coils of the first coil group and the second coil group, respectively. motor described in . The external connection terminals of the pair of phase bus bars connected to the same phase coils of the first system coil group and the second system coil group are arranged on opposite sides of a central axis. Item 3. The motor according to item 2. Among the plurality of phase bus bars, the phase bus bar having the longest length in the circumferential direction of the bus bar main body is arranged such that the coil terminals and the external connection terminals are arranged on opposite sides of the central axis. 4. The motor according to any one of claims 1 to 3. the coil terminals of the plurality of phase busbars extend radially outward with respect to the busbar main body,
Among the plurality of phase bus bars, the phase bus bar having the longest length along the circumferential direction of the bus bar main body overlaps at least a part of the other phase bus bars in the radial direction and overlaps with the other phase bus bars. Motor according to any one of claims 1 to 4 , located radially inward. The busbar unit is held by the busbar holder and has the same number of neutral point busbars as the number of systems of the coil group,
The neutral point bus bar is connected to the lead wire of each phase coil of the coil group of one system,
The neutral point busbar is
a busbar body extending along a plane perpendicular to the axial direction;
a plurality of coil terminals extending in one radial direction with respect to the busbar main body and connected to the lead wires;
The coil terminal of the neutral point bus bar and the coil terminal of the phase bus bar extend in the same radial direction with respect to each of the bus bar body portions. motor described in . 7. The motor according to claim 6 , wherein said neutral point bus bar and said phase bus bar at least partially overlap each other when viewed in the axial direction. 8. The motor according to claim 6 , wherein said neutral point bus bar is plate - shaped, and at least said bus bar main body portion is arranged with its axial direction as its thickness direction. The stator has a plurality of teeth around which coils are wound,
The system according to any one of claims 1 to 8 , wherein a plurality of U-phase coils, V-phase coils, and W-phase coils are provided in each system, and are provided across the plurality of teeth portions via connecting wires. motor. The motor according to any one of claims 1 to 9 , wherein the stator has 12 teeth around which coils are wound.

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