Method for manufacturing busbar unit, busbar unit, and motor

Abstract

To provide a manufacturing method for a bus bar unit that can accurately position a shield and a bus bar without using a dedicated part.SOLUTION: Manufacturing steps for a bus bar unit include a preparation step of a mold 200, a first step of positioning a bus bar 34 and a shield 37 in the mold, and a second step for forming the bus bar holder. The first step has a step for causing a plurality of first positioning pins 211 to hold the bus bar by inserting the plurality of first positioning pins 211 into a plurality of bus bar through-holes H15, a step for arranging a shield inside the mold in a state in which a bottom surface of the shield is in contact with tips of the first positioning pins, a step for positioning the shield in the vertical direction by bringing a second positioning pin 212 into contact with the top surface of the shield, and a step for positioning the bus bar in the vertical direction by bringing a third positioning pin extending from the lower surface of the upper die to the lower side in contact with the upper surface of the bus bar.SELECTED DRAWING: Figure 8

Description

[Technical field]

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

[0002] There is known a motor including a busbar unit that connects an external power supply terminal and a coil. Patent Document 1 discloses a busbar unit in which busbars and positioning members made of insulating resin are alternately laminated. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6353723 Summary of the Invention [Problem to be solved by the invention]

[0004] In the configuration described in Patent Document 1, the busbar can be positioned in a planar direction by the positioning member, but it is difficult to position the busbar and the positioning member in the direction in which they are stacked. In addition, since it is necessary to prepare multiple members dedicated to positioning, there are problems in that the number of parts is large and the cost of the parts themselves is high. [Means for solving the problem]

[0005] According to one aspect of the present invention, there is provided a method for manufacturing a busbar unit applicable to connecting a coil in a motor to an external power supply. The busbar unit includes a busbar made of a plate-shaped conductor, a thin shield that blocks magnetic fields generated from the busbar, and a busbar holder that holds the busbar and the shield. The busbar has an arc-shaped busbar main body held by the busbar holder with the plate surface facing up and down, and a plurality of busbar through holes that penetrate the busbar in the plate thickness direction. The shield has portions that overlap with the plurality of busbar through holes when viewed from the up and down direction. The process for manufacturing the busbar unit includes a step of preparing a mold for insert molding the busbar and the shield, a first step of positioning the busbar and the shield within the mold, and a second step of, after the first step, injecting resin into the mold to mold the busbar holder. The first process includes the steps of: inserting a plurality of first positioning pins extending upward from the upper surface of the lower mold of the mold into a plurality of busbar through holes to hold the busbar on the first positioning pins; placing the shield within the mold with the lower surface of the shield in contact with the tips of the first positioning pins; bringing a second positioning pin extending downward from the lower surface of the upper mold of the mold into contact with the upper surface of the shield to position the shield in the vertical direction; and bringing a third positioning pin extending downward from the lower surface of the upper mold into contact with the upper surface of the busbar to position the busbar in the vertical direction.

[0006] According to one aspect of the present invention, there is provided a busbar unit applicable to connecting a coil in a motor to an external power source. The busbar unit includes a busbar made of a plate-shaped conductor, a thin shield that shields magnetic fields generated from the busbar, and a busbar holder that holds the busbar and the shield. The busbar has an arc-shaped busbar main body that is held by the busbar holder with the plate surface facing up and down, and a plurality of busbar through holes that penetrate the busbar in the plate thickness direction. The shield has portions that overlap with the plurality of busbar through holes when viewed from the up and down direction. The busbar holder has a plurality of first pin insertion holes that open on a lower surface of the busbar holder, extend upward, pass through the busbar through holes, and reach the lower surface of the shield, a second pin insertion hole that opens on an upper surface of the busbar holder, extend downward, and reach the upper surface of the shield, and a third pin insertion hole that opens on an upper surface of the busbar holder, extend downward, and reach the upper surface of the busbar.

[0007] According to one aspect of the present invention, there is provided a motor including a rotor rotatable around a central axis extending in a vertical direction, an annular stator located radially outside the rotor, and a rotational position detection unit located above the stator and detecting a rotational position of the rotor. The stator includes a stator body having a coil and a stator core, and a busbar unit located between the stator core and the rotational position detection unit. The busbar unit includes a busbar made of a plate-shaped conductor, a thin shield that blocks magnetic fields generated from the busbar, and a busbar holder that holds the busbar and the shield. The busbar includes an arc-shaped busbar main body held by the busbar holder with the plate surface facing in the vertical direction, a plurality of busbar through holes penetrating the busbar in the plate thickness direction, and a coil wiring portion and an external power supply wiring portion extending from different ends of the busbar main body. The shield includes a plurality of through hole shielding portions that overlap the plurality of busbar through holes when viewed in the vertical direction. The external power supply wiring portion extends linearly from an end of the busbar main body portion toward the outer periphery when viewed from the top-bottom direction, and is arranged side by side in the width direction of the external power supply wiring portion. Among the plurality of through hole shielding portions, some of the through hole shielding portions are located in the external power supply wiring portion, and other some of the through hole shielding portions are located in the busbar main body portion or the coil wiring portion. Effect of the Invention

[0008] According to one aspect of the present invention, there is provided a method for manufacturing a busbar unit that enables accurate positioning of a shield and a busbar without using dedicated parts. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a cross-sectional view of a motor according to an embodiment. [Diagram 2] FIG. 2 is a perspective view of the busbar unit. [Diagram 3] FIG. 3 is a plan view of the busbar unit as viewed from above. [Figure 4]FIG. 4 is a plan view of the busbar unit as viewed from below. [Diagram 5] FIG. 5 is a plan view of the bus bar group as viewed from above. [Figure 6] FIG. 6 is a plan view of the bus bar group and the shield as viewed from below. [Figure 7] FIG. 7 is a plan view of the bus bar group and the shield as viewed from above. [Figure 8] FIG. 8 is a cross-sectional view of a mold illustrating a manufacturing process of the busbar unit. [Figure 9] FIG. 9 is a cross-sectional view of a mold illustrating a manufacturing process of the busbar unit. [Figure 10] 10A to 10C are cross-sectional views of a mold illustrating a manufacturing process of the busbar unit. [Figure 11] FIG. 11 is a cross-sectional view of a mold illustrating a manufacturing process of a busbar unit. [Figure 12] 12A to 12C are cross-sectional views of a mold illustrating a manufacturing process of the bus bar unit. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0011] A motor 1 according to an embodiment will be described with reference to FIGS. In this embodiment, the direction in which the central axis J of the motor 1 shown in FIG. 1 extends is simply referred to as the "axial direction". In this embodiment, the axial direction is the up-down direction. The upper side (+Z) corresponds to one axial side, and the lower side (-Z) corresponds to the other axial side. Moreover, the radial direction centered on the central axis J is simply referred to as the "radial direction". Within the radial direction, the direction approaching the central axis J is referred to as the radial inner side, and the direction away from the central axis J is referred to as the radial outer side. In this embodiment, the radial inner side corresponds to one radial side, and the radial outer side corresponds to the other radial side. Moreover, the circumferential direction centered on the central axis J is simply referred to as the "circumferential direction". Note that the terms "upper" and "lower" are simply names used to describe the relative positional relationships of the various parts, and the actual positional relationships may be other than those indicated by these names.

[0012] The motor 1 of this embodiment is mounted, for example, on an electric power steering device (not shown). The electric power steering device is mounted on a steering mechanism for wheels of an automobile. The electric power steering device is a device that reduces steering force by using a motor.

[0013] As shown in Fig. 1, the motor 1 of this embodiment includes a rotor 20 centered on a central axis J, a stator 30 disposed radially outward of the rotor 20, a housing 11, a plurality of bearings 15, 16, and a rotational position detection unit 60 that detects the rotation of the rotor 20. In this embodiment, the rotational position detection unit 60 is a resolver. The rotational position detection unit 60 has a resolver rotor 61 and a resolver stator 62. The rotational position detection unit 60 is not limited to a resolver, and may be a type that uses a Hall element or an MR element.

[0014] The motor 1 is an inner rotor type motor. The rotor 20 rotates about a central axis J relative to the stator 30. Although not specifically shown, the motor 1 may include a board that controls the rotation of the rotor 20.

[0015] The housing 11 accommodates the rotor 20 and the stator 30. The housing 11 is cylindrical and extends in the axial direction. The housing 11 has a peripheral wall 11a, a top wall 11b, a bottom wall 11c, and a bearing retaining wall portion 11d. The peripheral wall 11a is cylindrical and extends in the axial direction. The top wall 11b closes an upper opening of the peripheral wall 11a. The bottom wall 11c closes a lower opening of the peripheral wall 11a. The bottom wall 11c holds a bearing 16. The bearing retaining wall portion 11d is fixed to the peripheral wall 11a. The bearing retaining wall portion 11d holds a bearing 15.

[0016] The rotor 20 has a shaft 21, a rotor core 22, and a magnet 23. The shaft 21 is cylindrical and extends in the axial direction. The shaft 21 may be cylindrical and extends in the axial direction. The shaft 21 is supported by a plurality of bearings 15, 16 so as to be rotatable about a central axis J. The plurality of bearings 15, 16 are spaced apart from one another in the axial direction and supported by the housing 11. That is, the shaft 21 is supported by the housing 11 via the plurality of bearings 15, 16.

[0017] The shaft 21 protrudes upward beyond the bearing 15. A resolver rotor 61 is connected to the upper end of the shaft 21. The resolver rotor 61 is rotatable around the central axis J together with the shaft 21. A resolver stator 62 is disposed above the bearing holding wall portion 11d that holds the bearing 15. The resolver stator 62 is annular and surrounds the resolver rotor 61 from the radially outer side. The resolver stator 62 is located above a busbar unit 36, which will be described later.

[0018] The rotor core 22 is cylindrical and extends in the axial direction. The rotor core 22 has an outer diameter larger than that of the shaft 21. The rotor core 22 has an axial length smaller than that of the shaft 21. The inner peripheral surface of the rotor core 22 is fixed to the outer peripheral surface of the shaft 21. The rotor core 22 is fixed to the shaft 21 by press-fitting, adhesive bonding, or the like. The rotor core 22 is located between a pair of bearings 15, 16 in the axial direction. The magnet 23 is fixed to the outer periphery of the rotor core 22.

[0019] The stator 30 faces the rotor 20 with a radial gap therebetween. The stator 30 surrounds the rotor 20 from the radial outside over the entire circumferential direction. The stator 30 includes a stator core 31, an insulator 32, a coil 33, and a busbar unit .

[0020] The stator core 31 is annular about the central axis J. The stator core 31 is cylindrical and extends in the axial direction. The stator core 31 surrounds the rotor 20 from the radially outer side. The stator core 31 is made of a plurality of electromagnetic steel plates laminated in the axial direction. The stator core 31 is fixed to the inner circumferential surface of the housing 11. The stator core 31 and the housing 11 are fixed to each other by, for example, shrink fitting or press fitting.

[0021] The stator core 31 has a core back 31a and a plurality of teeth 31b. The core back 31a is cylindrical and centered on the central axis J. A radially outer surface of the core back 31a is fixed to an inner peripheral surface of the peripheral wall 11a. The teeth 31b protrude radially inward from a radially inner surface of the core back 31a. The plurality of teeth 31b are arranged at intervals from one another in the circumferential direction. A radially inner surface of each tooth 31b faces a radially outer surface of the rotor 20 with a gap therebetween.

[0022] The insulator 32 is attached to the stator core 31. The insulator 32 is made of an insulating material. The insulator 32 is made of, for example, resin. The insulator 32 is attached to each of the multiple teeth 31b. The coil 33 is attached to the stator core 31 via the insulator 32. A plurality of coils 33 are provided and aligned in the circumferential direction.

[0023] The motor 1 of this embodiment is a three-phase motor. The three phases are a U phase, a V phase, and a W phase. In the case of a three-phase motor, each of the coils 33 of the U phase, the V phase, and the W phase is electrically connected to a busbar unit 36.

[0024] 1, the busbar unit 36 ​​is located on the upper side (+Z side) of the stator core 31. In the present embodiment, the busbar unit 36 ​​is located between the stator core 31 and the bearing retaining wall portion 11d. The busbar unit 36 ​​may be located above the bearing retaining wall portion 11d. The busbar unit 36 ​​overlaps with the resolver stator 62 when viewed in the axial direction.

[0025] 2, the busbar unit 36 ​​includes a busbar group 34 consisting of a plurality of busbars, and a busbar holder 35 that holds the busbar group 34. The busbar group 34 includes eight busbars 341U, 341V, 341W, 341G, 342U, 342V, 342W, and 342G. In this embodiment, the busbar group 34 is insert molded into the busbar holder 35.

[0026] As shown in FIG. 3, the busbar holder 35 has a holder main body 351 having an annular shape when viewed in the axial direction, three support legs 352 protruding radially outward from the outer circumferential surface of the holder main body 351, and a connector portion 353 protruding radially outward from the outer circumferential surface of the holder main body 351. The busbar holder 35 has an inner hole 35a extending along the central axis J. The busbar holder 35 is made of resin. Ends of a plurality of busbars protrude radially outward from the outer circumferential surface of the busbar holder 35. FIG. 5 shows the busbar group 34 arranged to be held by the busbar holder 35. Each busbar constituting the busbar group 34 extends circumferentially inside the busbar holder 35, and at least a part of a connection terminal portion described later and a coil wiring portion and an external power supply wiring portion described later are exposed to the outside of the busbar holder 35.

[0027] As shown in Figs. 2 to 4, the support legs 352 are disposed at three positions on the holder body 351. The three support legs 352 are disposed at 120° intervals in the circumferential direction when viewed from the axial direction. The support legs 352 extend radially outward from the outer circumferential surface of the holder body 351 and are L-shaped so as to bend downward at the radially outer end. The lower ends of the support legs 352 come into contact with the stator core 31 or the insulator 32. The support legs 352 position the busbar unit 36 ​​in the axial direction relative to the stator core 31 or the insulator 32. The number of the support legs 352 may be two or less or four or more. The busbar holder 35 may be configured without the support legs 352.

[0028] The busbar unit 36 ​​is configured to be connectable to two systems of three-phase coils. FIG. 3 shows a schematic coil configuration of the motor 1 of this embodiment. The six coils 33 are configured of two systems of three-phase coils. That is, the motor 1 has a first system coil group 331 including one set of a U-phase coil 33U, a V-phase coil 33V, and a W-phase coil 33W, and a second system coil group 332 including another set of a U-phase coil 33U, a V-phase coil 33V, and a W-phase coil 33W. The positions and the number of the coils 33 are not limited to the form shown in FIG. 3. For example, each of the U-phase coil 33U, the V-phase coil 33V, and the W-phase coil 33W may be configured of a plurality of coils.

[0029] 5, the busbar group 34 has a first system busbar group 341 and a second system busbar group 342. The first system busbar group 341 has a first U-phase busbar 341U, a first V-phase busbar 341V, a first W-phase busbar 341W, and a first neutral point busbar 341G. The second system busbar group 342 has a second U-phase busbar 342U, a second V-phase busbar 342V, a second W-phase busbar 342W, and a second neutral point busbar 342G.

[0030] That is, busbar unit 36 ​​has a plurality of U-phase busbars, a plurality of V-phase busbars, and a plurality of W-phase busbars. More specifically, busbar group 34 includes first U-phase busbar 341U and second U-phase busbar 342U constituting the U-phase busbar group, first V-phase busbar 341V and second V-phase busbar 342V constituting the V-phase busbar group, and first W-phase busbar 341W and second W-phase busbar 342W constituting the W-phase busbar group.

[0031] The three coils of the first system coil group 331 shown in Fig. 3 are connected to the first system busbar group 341. The U-phase coil 33U of the first system coil group 331 is connected to the first U-phase busbar 341U and the first neutral point busbar 341G. The V-phase coil 33V of the first system coil group 331 is connected to the first V-phase busbar 341V and the first neutral point busbar 341G. The W-phase coil 33W of the first system coil group 331 is connected to the first W-phase busbar 341W and the first neutral point busbar 341G.

[0032] The three coils of the second system coil group 332 are connected to the second system busbar group 342. The U-phase coil 33U of the second system coil group 332 is connected to the second U-phase busbar 342U and the second neutral point busbar 342G. The V-phase coil 33V of the second system coil group 332 is connected to the second V-phase busbar 342V and the second neutral point busbar 342G. The W-phase coil 33W of the second system coil group 332 is connected to the second W-phase busbar 342W and the second neutral point busbar 342G.

[0033] 5, the first U-phase busbar 341U has a main line portion 41U extending in a plane perpendicular to the central axis J with the plate surface facing the axial direction, a connection terminal portion Tc for connecting a coil located at one end of the main line portion 41U, and a connection terminal portion Te for connecting an external power source located at the other end of the main line portion 41U. The main line portion 41U has a plate surface facing the axial direction and a side surface facing a direction perpendicular to the axial direction. The main line portion 41U also has a busbar main body portion 1aU extending in an arc shape along the circumferential direction around the central axis J, a coil wiring portion 1bU extending linearly from one end of the busbar main body portion 1aU toward the outer periphery of the busbar unit 36, and an external power source wiring portion 1cU extending linearly from the other end of the busbar main body portion 1aU toward the outer periphery of the busbar unit 36.

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

[0035] The first V-phase busbar 341V has a main line portion 41V extending in a plane perpendicular to the central axis J with the plate surface facing the axial direction, a connection terminal portion Tc for connecting a coil located at one end of the main line portion 41V, and a connection terminal portion Te for connecting an external power source located at the other end of the main line portion 41V. The main line portion 41V has a plate surface facing the axial direction and a side surface facing a direction perpendicular to the axial direction. The main line portion 41V has a busbar main body portion 1aV extending in an arc shape along the circumferential direction around the central axis J, a coil wiring portion 1bV extending linearly from one end of the busbar main body portion 1aV to the outer periphery of the busbar unit 36, and an external power wiring portion 1cV extending linearly from the other end of the busbar main body portion 1aV to the outer periphery of the busbar unit 36.

[0036] The second V-phase busbar 342V, like the first V-phase busbar 341V, has a main line portion 42V, a connection terminal portion Tc for connecting a coil, and a connection terminal portion Te for connecting an external power supply. The main line portion 42V has a plate surface facing the axial direction and a side surface facing a direction perpendicular to the axial direction. The main line portion 42V has a busbar main body portion 2aV extending in an arc shape along the circumferential direction about the central axis J, a coil wiring portion 2bV extending linearly from one end of the busbar main body portion 2aV to the outer periphery side of the busbar unit 36, and an external power supply wiring portion 2cV extending linearly from the other end of the busbar main body portion 2aV to the outer periphery side of the busbar unit 36.

[0037] The first W-phase busbar 341W has a main line portion 41W extending in a plane perpendicular to the central axis J with the plate surface facing the axial direction, a connection terminal portion Tc for connecting a coil located at one end of the main line portion 41W, and a connection terminal portion Te for connecting an external power source located at the other end of the main line portion 41W. The main line portion 41W has a plate surface facing the axial direction and a side surface facing a direction perpendicular to the axial direction. The main line portion 41W has a busbar main body portion 1aW extending in an arc shape along the circumferential direction around the central axis J, a coil wiring portion 1bW extending linearly from one end of the busbar main body portion 1aW to the outer periphery side of the busbar unit 36, and an external power source wiring portion 1cW extending linearly from the other end of the busbar main body portion 1aW to the outer periphery side of the busbar unit 36.

[0038] The second W-phase busbar 342W, like the first W-phase busbar 341W, has a main line portion 42W, a connection terminal portion Tc for connecting a coil, and a connection terminal portion Te for connecting an external power supply. The main line portion 42W has a plate surface facing the axial direction and a side surface facing a direction perpendicular to the axial direction. The main line portion 42W has a busbar main body portion 2aW extending in an arc shape along the circumferential direction about the central axis J, a coil wiring portion 2bW extending linearly from one end of the busbar main body portion 2aW to the outer periphery side of the busbar unit 36, and an external power supply wiring portion 2cW extending linearly from the other end of the busbar main body portion 2aW to the outer periphery side of the busbar unit 36.

[0039] The first neutral point busbar 341G has a main line portion 41G extending in a plane perpendicular to the central axis J with the plate surface facing in the axial direction, one and other ends of the main line portion 41G, and three connection terminal portions Tc for connecting coils located in the circumferential center of the main line portion 41G. The main line portion 41G has a plate surface facing the axial direction and a side surface facing in a direction perpendicular to the axial direction. The main line portion 41G has a busbar main body portion 1aG extending in an arc shape along the circumferential direction around the central axis J, and one and other ends of the busbar main body portion 1aG and three coil wiring portions 1bG extending in a straight line from the circumferential center to the outer periphery of the busbar unit 36.

[0040] The second neutral point busbar 342G, like the first neutral point busbar 341G, has a main line portion 42G and three connection terminal portions Tc for connecting coils. The main line portion 42G has a plate surface facing the axial direction and a side surface facing a direction perpendicular to the axial direction. The main line portion 42G has a busbar main body portion 2aG extending in an arc shape along the circumferential direction around the central axis J, and three coil wiring portions 2bG extending in a straight line from one and the other ends of the busbar main body portion 2aG and the circumferential center portion to the outer periphery of the busbar unit 36.

[0041] The busbar unit 36 ​​may be configured without the first neutral point busbar 341G and the second neutral point busbar 342G. Using the first neutral point busbar 341G and the second neutral point busbar 342G makes it easier to simplify the wiring structure of the jumper wires that connect the coils 33 together, which is advantageous for improving productivity.

[0042] 5, the multiple bus bars constituting the bus bar group 34 are arranged in the circumferential direction centered on the central axis J. Of the multiple bus bars, the first W-phase bus bar 341W and the second W-phase bus bar 342W are located at the radially innermost positions. First V-phase bus bar 341V and first neutral point bus bar 341G are arranged radially outward from first W-phase bus bar 341W. First U-phase bus bar 341U is arranged radially outward from first V-phase bus bar 341V. A second V-phase bus bar 342V and a second neutral point bus bar 342G are arranged radially outward from second W-phase bus bar 342W. A second U-phase bus bar 342U is arranged radially outward from second V-phase bus bar 342V.

[0043] As shown in FIG. 5, the first system busbar group 341 and the second system busbar group 342 are respectively arranged in two adjacent regions with a first virtual line VL1 passing through the central axis J as a boundary when viewed in the axial direction. Furthermore, in this embodiment, the first U-phase busbar 341U and the second U-phase busbar 342U have shapes that are line-symmetrical with respect to the first virtual line VL1 as an axis of symmetry, and are arranged at positions that are line-symmetrical with respect to the first virtual line VL1 as an axis of symmetry. Similarly, the first V-phase busbar 341V and the second V-phase busbar 342V have shapes that are line-symmetrical with respect to the first virtual line VL1 as an axis of symmetry, and are arranged at positions that are line-symmetrical with respect to the first virtual line VL1 as an axis of symmetry. The first W-phase busbar 341W and the second W-phase busbar 342W have shapes that are line-symmetrical with respect to the first virtual line VL1 as an axis of symmetry, and are arranged at positions that are line-symmetrical with respect to the first virtual line VL1 as an axis of symmetry. First neutral point busbar 341G and second neutral point busbar 342G have shapes that are line-symmetrical with respect to first virtual line VL1, and are disposed at line-symmetrical positions.

[0044] The busbars are manufactured by bending blanks obtained by punching out a metal plate with a die. In this embodiment, two busbars arranged at symmetrical positions across the first virtual line VL1 have shapes that are line-symmetrical to each other, and therefore these two busbars can be manufactured using a common blank. That is, the first U-phase busbar 341U and the second U-phase busbar 342U can be manufactured from a common blank. Similarly, the first V-phase busbar 341V and the second V-phase busbar 342V, the first W-phase busbar 341W and the second W-phase busbar 342W, and the first neutral point busbar 341G and the second neutral point busbar 342G can also be manufactured using a common blank.

[0045] According to this embodiment, the eight bus bars constituting the bus bar unit 36 ​​can be manufactured from four types of blanks. This makes it possible to reduce the number of dies used to manufacture the bus bars, enabling the bus bars to be manufactured efficiently and at low cost. This allows the productivity of the bus bar unit 36 ​​to be improved.

[0046] In this embodiment, the busbars having line-symmetric shapes are arranged in line-symmetric positions about the first virtual line VL1. With this configuration, the first busbar group 341 and the second busbar group 342 are arranged in line-symmetric positions about the first virtual line VL1. The busbar holder 35 that holds the busbar group 34 can be easily formed into a ring shape that is close to a perfect circle, and can be easily arranged above the ring-shaped stator core 31.

[0047] In the present embodiment, both the shape and the arrangement of the paired busbars are configured to be line-symmetrical with respect to the first virtual line VL1, but the present invention is not limited to this configuration. The first U-phase busbar 341U and the second U-phase busbar 342U only need to have their main line portions 41U and 42U each having a shape that is line-symmetrical with respect to the first virtual line VL1. The same is true for the first V-phase busbar 341V and the second V-phase busbar 342V, the first W-phase busbar 341W and the second W-phase busbar 342W, and the first neutral point busbar 341G and the second neutral point busbar 342G. If the main line portions have shapes that are line-symmetrical with each other, it is possible to use the same blank for manufacturing the busbars, thereby improving the manufacturing efficiency of the busbars.

[0048] The shapes of the connection terminal portions Tc, Te, which are portions other than the main line portion, are changed according to the position and orientation of the lead wire extending from the coil 33. For example, the orientation of the opening of the coil connection connection terminal portion Tc that holds the lead wire from the coil 33 may differ between the first U-phase bus bar 341U and the second U-phase bus bar 342U. Even in this case, the two blanks, which differ only in shape at the portions forming the connection terminals Tc and Te, can be manufactured by using a common punched shape from a metal plate and performing only a small amount of cutting after punching, thereby reducing the number of dies used to manufacture the blanks.

[0049] In this embodiment, as shown in Fig. 5, the first U-phase busbar 341U, the second U-phase busbar 342U, the first V-phase busbar 341V, the second V-phase busbar 342V, the first W-phase busbar 341W, the second W-phase busbar 342W, the first neutral point busbar 341G, and the second neutral point busbar 342G are arranged at positions where they do not overlap each other when viewed from the axial direction. The eight busbars are arranged at positions where they overlap at least one other busbar when viewed from the radial direction. In this embodiment, the main line portions of the eight busbars are arranged on a common plane with the plate surfaces facing the axial direction. According to this configuration, the multiple busbars can be arranged in positions where they overlap when viewed from the radial direction, and the multiple busbars are arranged with their plate surfaces facing the axial direction, which significantly reduces the axial thickness of the busbar unit 36. By using the busbar unit 36 ​​of this embodiment, it is possible to realize a stator 30 and a motor 1 that are compact in the axial direction.

[0050] As shown in FIG. 5, each bus bar constituting bus bar group 34 has a wide portion that protrudes in a direction perpendicular to the axial direction from a side surface of the bus bar when viewed in the axial direction.

[0051] The first U-phase busbar 341U has a wide portion 1dU that protrudes from a side surface of the external power supply wiring portion 1cU toward the external power supply wiring portion 1cV (right side in FIG. 5) at an intersection between the busbar main body 1aU and the external power supply wiring portion 1cU. The second U-phase busbar 342U has a wide portion 2dU that protrudes from a side surface of the external power supply wiring portion 2cU toward the external power supply wiring portion 2cV (left side in FIG. 5) at an intersection between the busbar main body 2aU and the external power supply wiring portion 2cU.

[0052] The first U-phase busbar 341U has two busbar through holes H11, H12 penetrating the main line portion 41U in the plate thickness direction (axial direction) at the position of the wide portion 1dU. The second U-phase busbar 342U has two busbar through holes H21, H22 penetrating the main line portion 42U in the plate thickness direction at the position of the wide portion 2dU. The two busbar through holes H11, H12 of the first U-phase busbar 341U are aligned along the direction in which the external power supply wiring portion 1cU extends. The two busbar through holes H21, H22 of the second U-phase busbar 342U are aligned along the direction in which the external power supply wiring portion 2cU extends. The busbar through holes H11, H12 are holes into which support pins are inserted to fix each busbar in a mold when the busbar group 34 is insert-molded into the busbar holder 35. The same applies to the other bus bar through holes H13 to H19 and bus bar through holes H23 to H29 described later.

[0053] The first V-phase busbar 341V has a wide portion 1dV at an inner corner of the position where the busbar main body 1aV and the coil wiring portion 1bV intersect. The first V-phase busbar 341V has a wide portion 1eV at the intersection of the busbar main body 1aV and the external power supply wiring portion 1cV, which protrudes from a side surface of the external power supply wiring portion 1cV toward the external power supply wiring portion 1cW (right side in FIG. 5). The first V-phase busbar 341V has two busbar through holes H13 and H14 that penetrate the wide portions 1dV and 1eV in the plate thickness direction, respectively.

[0054] The second V-phase busbar 342V has a wide portion 2dV at an inner corner of the position where the busbar main body 2aV and the coil wiring portion 2bV intersect. The second V-phase busbar 342V has a wide portion 2eV at the intersection of the busbar main body 2aV and the external power supply wiring portion 2cV, which protrudes from the side surface of the external power supply wiring portion 2cV to the external power supply wiring portion 2cW side (left side in FIG. 5). The second V-phase busbar 342V has two busbar through holes H23 and H24 that penetrate the wide portions 2dV and 2eV in the plate thickness direction, respectively.

[0055] The first W-phase busbar 341W has a wide portion 1dW at an inner corner of a position where the busbar main body 1aW and the coil wiring portion 1bW intersect. The first W-phase busbar 341W has a wide portion 1eW at an intersection between the busbar main body 1aW and the external power supply wiring portion 1cW, which protrudes from a side surface of the external power supply wiring portion 1cW to the external power supply wiring portion 1cV side (left side in FIG. 5). The first W-phase busbar 341W has a wide portion 1fW at a center of the busbar main body 1aW, which protrudes radially outward from a side surface of the busbar main body 1aW. The first W-phase busbar 341W has three busbar through holes H15, H16, and H17 that penetrate the wide portions 1dW, 1eW, and 1fW in the plate thickness direction, respectively.

[0056] The second W-phase busbar 342W has a wide portion 2dW at an inner corner of a position where the busbar main body 2aW and the coil wiring portion 2bW intersect. The second W-phase busbar 342W has a wide portion 2eW at an intersection between the busbar main body 2aW and the external power supply wiring portion 2cW, which protrudes from a side surface of the external power supply wiring portion 2cW to the external power supply wiring portion 2cV side (right side in FIG. 5). The second W-phase busbar 342W has a wide portion 2fW at a center of the busbar main body 2aW, which protrudes radially outward from a side surface of the busbar main body 2aW. The second W-phase busbar 342W has three busbar through holes H25, H26, and H27 that penetrate the wide portions 2dW, 2eW, and 2fW in the plate thickness direction, respectively.

[0057] The first neutral point busbar 341G has a wide portion 1dG that protrudes circumferentially outward from a corner where the busbar main body 1aG and the coil wiring portion 1bG on one circumferential side are connected. The first neutral point busbar 341G has a wide portion 1eG that protrudes circumferentially outward from a corner where the busbar main body 1aG and the coil wiring portion 1bG on the other circumferential side are connected. The first neutral point busbar 341G has two busbar through holes H18, H19 that penetrate the wide portions 1dG, 1eG in the plate thickness direction, respectively.

[0058] The second neutral point busbar 342G has a wide portion 2dG that protrudes circumferentially outward from a corner where the busbar main body 2aG and the coil wiring portion 2bG on one circumferential side are connected. The second neutral point busbar 342G has a wide portion 2eG that protrudes circumferentially outward from a corner where the busbar main body 2aG and the coil wiring portion 2bG on the other circumferential side are connected. The second neutral point busbar 342G has two busbar through holes H28, H29 that penetrate the wide portions 2dG, 2eG in the plate thickness direction, respectively.

[0059] According to this embodiment, each busbar belonging to busbar group 34 has a wide portion that protrudes from a side surface of each busbar in a direction perpendicular to the axial direction when viewed in the axial direction, thereby preventing the electrical resistance of the busbar from increasing even when the busbar has a busbar through hole. In this embodiment, the through hole of the busbar may be located in the wide portion of the busbar, as in busbar through holes H13 to H19 and H23 to H29 shown in Fig. 5, or may be located near wide portions 1dU and 2dU, as in busbar through holes H11, H12, H21 and H22. By configuring the busbar through holes to be located in the wide portion, an increase in the electrical resistance of the busbar due to the through holes is almost eliminated, so that the through holes for inserting support pins can be located in any position.

[0060] In this embodiment, wide portion 1dV of first V-phase busbar 341V, wide portion 2dV of second V-phase busbar 342V, wide portion 1dW of first W-phase busbar 341W, and wide portion 2dW of second W-phase busbar 342W are located inside the corners where the respective busbars are bent. This configuration can increase the rigidity of each busbar. It is possible to reduce the bending of the busbars, which can improve the yield of busbar unit 36 ​​and reduce defects in the coil wiring.

[0061] In this embodiment, wide portions 1dv, 1eV of first V-phase busbar 341V and wide portions 2dV, 2eV of second V-phase busbar 342V are located at both circumferential ends of first V-phase busbar 341V and second V-phase busbar 342V, respectively. Similarly, wide portions 1dW, 1eW of first W-phase busbar 341W and wide portions 2dW, 2eW of second W-phase busbar 342W are located at both circumferential ends of first W-phase busbar 341W and second W-phase busbar 342W, respectively. According to these configurations, by providing the busbar through holes in the wide portion, it is possible to arrange the busbar through holes for inserting the support pins at both ends of the elongated busbar, so that even a relatively long busbar can be stably held. The positional accuracy of the busbar during insert molding can be improved. The yield of the busbar unit 36 ​​can be improved and defects in the coil wiring can be reduced.

[0062] In this embodiment, the first U-phase busbar 341U, the second U-phase busbar 342U, the first V-phase busbar 341V, the second V-phase busbar 342V, the first W-phase busbar 341W, and the second W-phase busbar 342W have external power supply wiring portions 1cU, 2cU, 1cV, 2cV, 1cW, and 2cW extending in a direction along the first virtual line VL1 in a part of the main line portions 41U, 42U, 41V, 42V, 41W, and 42W, respectively. An external power supply connection terminal portion Te extends from the tip of the external power supply wiring portions 1cU, 2cU, 1cV, 2cV, 1cW, and 2cW. The multiple external power supply wiring portions 1cU, 2cU, 1cV, 2cV, 1cW, and 2cW are arranged in a direction perpendicular to the first virtual line VL1 when viewed in the axial direction. The external power supply wiring portions 1cU, 2cU, 1cV, 2cV, 1cW, and 2cW are held by a connector portion 353 of the bus bar holder 35 shown in Figures 2 to 4. The respective tips of the external power supply wiring portions 1cU, 2cU, 1cV, 2cV, 1cW, and 2cW protrude from the connector portion 353 to the outer periphery of the bus bar unit 36.

[0063] According to this configuration, the multiple external power supply wiring portions 1cU, 2cU, 1cV, 2cV, 1cW, and 2cW are housed in a partial circumferential region of the bus bar holder 35, allowing the external power supply wiring portions to be arranged compactly. The multiple external power supply wiring portions are aligned along the first virtual line VL1, allowing both the external power supply wiring portions 1cU, 1cV, and 1cW of the first bus bar group 341 and the external power supply wiring portions 2cU, 2cV, and 2cW of the second bus bar group 342 to be arranged near the first virtual line VL1. The connectors to the two external power supplies can be configured compactly.

[0064] As shown in FIG. 5, the first system external power supply wiring sections 1cV, 1cW have wide portions 1eV, 1eW protruding from opposing side surfaces, and the two wide portions 1eV, 1eW overlap each other when viewed from the extension direction of the external power supply wiring sections 1cV, 1cW. Also in the second system, the external power supply wiring portions 2cV, 2cW have wide portions 2eV, 2eW protruding from opposing side surfaces, and the two wide portions 2eV, 2eW overlap each other when viewed from the extension direction of the external power supply wiring portions 2cV, 2cW. According to these configurations, two wide portions 1eV, 1eW are arranged in the gap between adjacent external power supply wiring portions 1cV, 1cW. Two wide portions 2eV, 2eW are arranged in the gap between external power supply wiring portions 2cV, 2cW. Since the wide portions 1eV, 1eW, 2eV, 2eW can be arranged efficiently, the connector to the external power supply can be configured compactly. In addition, since the width between the external power supply wiring portions is not excessively large, molding defects of the resin in the gap between the external power supply wiring portions can be suppressed.

[0065] In this embodiment, wide portion 1dU of first U-phase bus bar 341U is disposed between adjacent external power supply wiring portions 1cU and 1cV. Wide portion 2dU of second U-phase bus bar 342U is disposed between adjacent external power supply wiring portions 2cU and 2cV. This configuration prevents the gaps between adjacent external power supply wiring portions 1cU and 1cV and the gaps between adjacent external power supply wiring portions 2cU and 2cV from becoming excessively large, and suppresses molding defects of resin from occurring in the gaps between the external power supply wiring portions.

[0066] The busbar unit 36 ​​has a shield 37 that overlaps with the busbar group 34 when viewed in the axial direction. The shield 37 is a circular metal thin plate when viewed in the axial direction. The shield 37 is located on the upper side (+Z side) of the busbar group 34. In other words, the shield 37 is located between the busbar group 34 and the resolver stator 62 in the axial direction. The shield 37 shields the resolver stator 62, which is an electronic circuit part of the rotational position detection unit 60, from magnetism generated from the busbar group 34.

[0067] 6 and 7, when viewed in the axial direction, the inner peripheral edge of shield 37 is located slightly radially inward of the inner peripheral edge of busbar main body portion 1aW of first W-phase busbar 341W and the inner peripheral edge of busbar main body portion 2aW of second W-phase busbar 342W. When viewed in the axial direction, the outer peripheral edge of shield 37 substantially overlaps with the inner peripheral edge of busbar main body portion 1aU of first U-phase busbar 341U and the inner peripheral edge of busbar main body portion 2aU of second U-phase busbar 342U, as well as the inner peripheral edge of busbar main body portion 1aG of first neutral point busbar 341G and the inner peripheral edge of busbar main body portion 2aG of second neutral point busbar 342G.

[0068] 7, shield 37 covers busbar main body portion 1aV of first V-phase busbar 341V, busbar main body portion 2aV of second V-phase busbar 342V, busbar main body portion 1aW of first W-phase busbar 341W, and busbar main body portion 2aW of second W-phase busbar 342W from above. Shield 37 may also be sized to cover portions of first U-phase busbar 341U, second U-phase busbar 342U, first neutral point busbar 341G, and second neutral point busbar 342G, as necessary.

[0069] Figures 8 to 12 are explanatory views of the manufacturing process of the busbar unit 36. The cross-sectional views of the busbar and the shield shown in Figures 8 to 12 are cross-sectional views taken along lines VIII-VIII, IX-IX, XX, XI-XI, and XII-XII shown in Figure 7, respectively, with the right side corresponding to the central axis J side.

[0070] The busbar unit 36 ​​is manufactured by insert molding the busbar group 34 and the shield 37 together into the busbar holder 35. Most of the busbar group 34 is embedded in the busbar holder 35, with only the connection terminals Tc, Te located at the ends and their surroundings exposed from the busbar holder 35. Almost the entire shield 37 is embedded inside the busbar holder 35.

[0071] The process of manufacturing the busbar unit 36 ​​includes a preparation step of preparing a mold 200 (see FIG. 8) for insert molding the busbar group 34 and the shield 37, a first step of positioning the busbar group 34 and the shield 37 within the mold 200, and, after the first step, a second step of injecting resin into the mold 200 to form the busbar holder 35.

[0072] As shown in Fig. 8, the mold 200 has an upper mold 201 and a lower mold 202 arranged one above the other. In this embodiment, the lower mold 202 has a recess 202a that opens upward. The upper mold 201 is plate-shaped and covers the opening of the recess 202a from above. The mold 200 can seal the opening of the recess 202a by bringing a lower surface 201a of the upper mold 201 into contact with an upper end surface 202b of the lower mold 202. An internal space 203 of the mold 200 surrounded by the upper mold 201 and the lower mold 202 is filled with a resin material that will become the bus bar holder 35.

[0073] In the first step, the busbar group 34 and the shield 37 are placed in the recess 202a of the lower mold 202. As shown in Fig. 8 to Fig. 12, the busbar group 34 is placed on the bottom side of the recess 202a, and the shield 37 is placed above the busbar group 34. The busbar group 34 and the shield 37 are fixed at predetermined positions in the internal space 203 by a plurality of positioning pins extending upward from the bottom surface 202c of the lower mold 202 and a plurality of positioning pins extending downward from the lower surface 201a of the upper mold 201.

[0074] The mold 200 has a first positioning pin 211 extending upward from the bottom surface 202c of the lower mold 202 shown in Figure 8, a second positioning pin 212 extending downward from the lower surface 201a of the upper mold 201, a third positioning pin 213 extending downward from the lower surface 201a of the upper mold 201 shown in Figure 10, a fourth positioning pin 214 extending upward from the bottom surface 202c of the lower mold 202 shown in Figure 9, a fifth positioning pin 215 extending upward from the bottom surface 202c of the lower mold 202 shown in Figure 10, and a sixth positioning pin 216 extending upward from the bottom surface 202c of the lower mold 202 shown in Figure 12. The mold 200 has six kinds of positioning pins, namely, a first positioning pin 211 to a sixth positioning pin 216, each of which has a plurality of pins.

[0075] First positioning pins 211 are inserted into the busbar through holes H11 to H19 and H21 to H29 of the busbar group 34 installed in the recess 202a. The first positioning pins 211 are cylindrical. The first positioning pins 211 pass through the busbar through holes H11 to H19 and H21 to H29 from the bottom to the top. The top ends of the first positioning pins 211 protrude upward from the top ends of the busbar through holes H11 to H19 and H21 to H29.

[0076] Some of the bus bars in bus bar group 34 are supported from below by fifth positioning pin 215 shown in Fig. 10. Fifth positioning pin 215 is cylindrical and extends in the vertical direction. As shown in Fig. 6, fifth positioning pin 215 supports the lower surfaces of first V-phase bus bar 341V, first W-phase bus bar 341W, second V-phase bus bar 342V, and second W-phase bus bar 342W from below.

[0077] Fifth positioning pin 215 is disposed at the circumferential center of arc-shaped busbar main bodies 1aV, 2aV of the V-phase busbar. The fifth positioning pin 215 is disposed at two locations on each of the arc-shaped busbar main bodies 1aW and 2aW of the W-phase busbar. In the busbar main body 1aW, the fifth positioning pin 215 is disposed at an intermediate position between the wide portions 1dW and 1fW and an intermediate position between the wide portions 1eW and 1fW. In the busbar main body 2aW, the fifth positioning pin 215 is disposed at an intermediate position between the wide portions 2dW and 2fW and an intermediate position between the wide portions 2eW and 2fW.

[0078] First positioning pins 211 are inserted into busbar through holes H11 to H19, H21 to H29 of the eight busbars, and each busbar has two or more busbar through holes. With this configuration, each busbar is positioned by first positioning pins 211 in the horizontal direction perpendicular to the up-down direction.

[0079] After the busbar group 34 is placed in the recess 202a, a shield 37 is placed on the upper side of the busbar group 34. The shield 37 is supported by a first positioning pin 211 extending upward from the bottom surface of the lower mold 202, a fourth positioning pin 214, a sixth positioning pin 216, and a second positioning pin 212 extending downward from the top surface of the upper mold 201.

[0080] 8, first positioning pins 211 contact lower surface 37a of shield 37 from below. Specifically, six first positioning pins 211 passing through busbar through holes H13 and H14 of first V-phase busbar 341V, busbar through hole H15 of first W-phase busbar 341W, busbar through holes H23 and H24 of second V-phase busbar 342V, and busbar through hole H25 of second W-phase busbar 342W shown in FIG. 7 support shield 37 from below.

[0081] In the present embodiment, the six first positioning pins 211 supporting the shield 37 are disposed relatively dispersedly in the circumferential direction. The positions of the two first positioning pins 211 passing through the busbar through holes H15 and H25 are located on the opposite side of the central axis J from the positions of the two first positioning pins 211 passing through the busbar through holes H14 and H24, as viewed from above. The two first positioning pins 211 passing through the busbar through holes H13 and H23 are disposed relatively far from the four first positioning pins 211 passing through the busbar through holes H15, H25, H14, and H24 in the circumferential direction. According to this configuration, the first positioning pins 211 supporting the shield 37 from below are disposed at intervals without being biased in the circumferential direction, so that the shield 37 can be prevented from tilting or warping.

[0082] In this embodiment, the external power supply wiring parts 1cU, 1cV, 1cW, 2cU, 2cV, and 2cW have busbar through holes H11, H12, H14, H16, H21, H22, H24, and H26. According to this configuration, when the busbar unit 36 ​​is manufactured, the external power supply wiring parts 1cU, 1cV, 1cW, 2cU, 2cV, and 2cW are fixed in the horizontal direction by the first positioning pins 211 inserted into the busbar through holes H11, H12, H14, H16, H21, H22, H24, and H26, so that the positional accuracy of the external power supply wiring parts 1cU, 1cV, 1cW, 2cU, 2cV, and 2cW, which serve as connection terminals to the external power supply, can be improved. The busbar unit 36 ​​that is less likely to have poor connection with the external power supply can be manufactured.

[0083] In this embodiment, the busbars constituting the busbar group 34 may have busbar through holes in a range of ±45 degrees from the center position of the connector portion 353 where the multiple external power supply wiring portions 1cU, 1cV, 1cW, 2cU, 2cV, and 2cW are located in the circumferential direction centered on the central axis J. In this embodiment, the central axis J coincides with the central axis of the inner hole 35a of the busbar holder 35. FIG. 4 shows a second virtual line VL2 connecting the central axis J and the circumferential center position of the connector portion 353, and a range α of ±45 degrees in the circumferential direction from the second virtual line VL2. If the busbar through holes are arranged within the range α shown in FIG. 4, it is possible to obtain an effect of improving the positional accuracy of the multiple external power supply wiring portions 1cU, 1cV, 1cW, 2cU, 2cV, and 2cW by the first positioning pin 211.

[0084] When the first positioning pin 211 is in a position where it supports the shield 37 from below, the shield 37 shields the busbar through holes H13, H14, H15, H23, H24, and H25 as viewed from the top-bottom direction. That is, the shield 37 has a plurality of through hole shielding portions that overlap the busbar through holes H13, H14, H15, H23, H24, and H25 as viewed from the top-bottom direction. Among the plurality of through hole shielding portions in the shield 37, the through hole shielding portions that shield the busbar through holes H14 and H24 are located in the external power supply wiring portions 1cV and 2cV, and the through hole shielding portions that shield the other busbar through holes H13, H15, H23, and H25 are located in the busbar main body portions 1aV, 1aW, 2aV, and 2aW or the coil wiring portions 1bV, 1bW, 2bV, and 2bW.

[0085] The fourth positioning pin 214 is inserted into the shield through hole 37d shown in Figs. 6 and 7. The shield through hole 37d is a hole that penetrates the shield 37 in the up-down direction. The shield through hole 37d is disposed at a position that does not overlap with the bus bar group 34 when viewed in the up-down direction. The fourth positioning pin 214 is cylindrical. As shown in Fig. 9, the fourth positioning pin 214 extends upward from the bottom surface 202c of the lower mold 202 and is inserted into the shield through hole 37d from below. The upper end of the fourth positioning pin 214 protrudes upward beyond the upper surface of the shield 37. In this embodiment, the shield 37 has two shield through holes 37d.

[0086] As shown in FIG. 6, the sixth positioning pins 216 are located at three positions on the lower surface of the shield 37. The sixth positioning pins 216 are cylindrical. As shown in FIG. 12, the sixth positioning pins 216 extend upward from the bottom surface 202c of the lower mold 202 and contact the lower surface 37a of the shield 37. The sixth positioning pins 216 support the shield 37 from below together with the first positioning pins 211. That is, the shield 37 is supported from below by a total of nine positioning pins. The sixth positioning pins 216 are disposed at positions where the circumferential intervals of the six first positioning pins 211 supporting the shield 37 are wide. The sixth positioning pins 216 make it easier to hold the shield 37 in a horizontal position.

[0087] After the busbar group 34 and the shield 37 are placed in the recess 202a, the upper die 201 is moved downward and placed in the closed position. The closed position is a position where the lower surface 201a of the upper die 201 abuts against the upper end surface 202b of the lower die 202. By placing the upper die 201 in the closed position, the opening of the recess 202a is closed.

[0088] 8 to 11, the upper mold 201 has a second positioning pin 212 and a third positioning pin 213. The second positioning pin 212 and the third positioning pin 213 are both cylindrical pins extending downward from the lower surface 201a of the upper mold 201.

[0089] As shown in Figures 8 and 12, the second positioning pin 212 is disposed at a position overlapping the first positioning pin 211 and the sixth positioning pin 216, which support the shield 37 from below, as viewed from above. As shown in Figures 8 and 12, the second positioning pin 212 sandwiches the shield 37 between itself and the first positioning pin 211 and between itself and the sixth positioning pin 216, and fixes it in the vertical direction. Therefore, the step of disposing the upper mold 201 at the closed position is a step of bringing the second positioning pin 212 into contact with the upper surface 37b of the shield 37 to position the shield 37 in the vertical direction.

[0090] As shown in FIG. 7, the third positioning pin 213 is disposed at a position overlapping with the fifth positioning pin 215 (see FIG. 6) that supports the shield 37 from below, as viewed from above. The third positioning pin 213 passes through a shield notch 37c that is cut so as to penetrate the shield 37 from above and below. In the case of this embodiment, the shield notch 37c is a notch that opens toward the inside in the radial direction. As shown in FIG. 10, the third positioning pin 213 sandwiches the bus bar between itself and the fifth positioning pin 215 and fixes it in the vertical direction. Therefore, the process of disposing the upper mold 201 in the closed position is a process of bringing the third positioning pin 213 into contact with the upper surface of the bus bar to position the bus bar in the vertical direction.

[0091] Through the above-described first step, the busbar group 34 and the shield 37 are positioned and fixed in the internal space of the mold 200. In the subsequent second step, resin is injected into the mold 200 to form the busbar holder 35. Through the above-described steps, the busbar unit 36 ​​is manufactured.

[0092] According to the method for manufacturing the busbar unit 36 ​​of this embodiment, the busbar group 34 and the shield 37 can be positioned in the vertical and horizontal directions using positioning pins provided on the upper die 201 and the lower die 202. It is possible to easily manufacture the busbar unit 36 ​​in which the busbar group 34 and the shield 37 are accurately positioned, without using any dedicated parts for positioning the insert parts.

[0093] In the present embodiment, a configuration has been described in which both the busbar group 34 and the shield 37 can be positioned in the vertical and horizontal directions, but a configuration may be adopted in which a horizontal positioning mechanism for the shield 37 is not provided. That is, the busbar unit 36 ​​may be manufactured using a mold 200 that does not include the fourth positioning pin 214 that positions the shield 37 in the horizontal direction. If a shield 37 that is sufficiently large when viewed from the vertical direction is used, the magnetism generated from the busbar group 34 can be shielded even if the horizontal position of the shield 37 is slightly misaligned.

[0094] The busbar unit 36 ​​obtained by the manufacturing method of this embodiment has a plurality of pin insertion holes opening in the upper or lower surface of the busbar holder 35, as shown in FIGS.

[0095] 4, the busbar holder 35 has a plurality of first pin insertion holes Hp1 that open on the lower surface of the busbar holder 35 and extend upward. The first pin insertion holes Hp1 are holes that are formed by the first positioning pins 211 during the manufacturing process of the busbar unit 36. Therefore, the first pin insertion holes Hp1 are holes that pass through the busbar through holes and reach the lower surface of the shield 37.

[0096] 3, the busbar holder 35 has a plurality of second pin insertion holes Hp2 that open on the upper surface of the busbar holder 35 and extend downward. The second pin insertion holes Hp2 are holes that are formed by second positioning pins 212 during the manufacturing process of the busbar unit 36. The second positioning pins 212 are pins that press the shield 37 from above at positions that vertically overlap the first positioning pins 211 and the sixth positioning pins 216 that support the shield 37 from below. Therefore, the second pin insertion holes Hp2 are holes that extend downward from the upper surface of the busbar holder 35 and reach the upper surface 37b of the shield 37.

[0097] As shown in Fig. 3, the busbar holder 35 has a plurality of third pin insertion holes Hp3 that open on the upper surface of the busbar holder 35 and extend downward. The third pin insertion holes Hp3 are holes formed by third positioning pins 213 during the manufacturing process of the busbar unit 36. As shown in Figs. 10 and 11, the third positioning pins 213 hold the busbar by sandwiching it between themselves and fifth positioning pins 215 extending from the lower mold 202 from above and below. Therefore, the third pin insertion holes Hp3 are holes that extend downward from the upper surface of the busbar holder 35 and reach the upper surface of the busbar.

[0098] As shown in FIG. 3 and FIG. 4, the busbar holder 35 has a plurality of fourth pin insertion holes Hp4 that vertically penetrate the busbar holder 35. The fourth pin insertion holes Hp4 are holes that are formed by the fourth positioning pins 214 in the manufacturing process of the busbar unit 36. As shown in FIG. 9, the fourth positioning pins 214 extend upward from the lower die 202 and reach the upper die 201 through the shield through holes 37d. Therefore, the fourth pin insertion holes Hp4 are holes that extend upward from the lower surface of the busbar holder 35 and pass through the shield through holes 37d to reach the upper surface of the busbar holder 35. Note that the fourth positioning pins 214 may have a length that does not reach the upper die 201. In this case, the fourth pin insertion holes Hp4 open only to the lower surface of the busbar holder 35.

[0099] As shown in Fig. 4, the busbar holder 35 has a plurality of fifth pin insertion holes Hp5 that open on the lower surface of the busbar holder 35 and extend upward. The fifth pin insertion holes Hp5 are holes formed by the fifth positioning pins 215 during the manufacturing process of the busbar unit 36. As shown in Figs. 10 and 11, the fifth positioning pins 215 hold the busbar by sandwiching it between themselves and the third positioning pins 213 from above and below. Therefore, the fifth pin insertion holes Hp5 are holes that extend upward from the lower surface of the busbar holder 35 and reach the lower surface of the busbar.

[0100] 4, the busbar holder 35 has a plurality of sixth pin insertion holes Hp6 that open on the lower surface of the busbar holder 35 and extend upward. The sixth pin insertion holes Hp6 are holes that are formed by sixth positioning pins 216 during the manufacturing process of the busbar unit 36. The sixth positioning pins 216 hold the busbars by sandwiching them between themselves and the second positioning pins 212 from above and below, as shown in FIG. 12. Therefore, the sixth pin insertion holes Hp6 are holes that extend upward from the lower surface of the busbar holder 35 and reach the lower surface 37a of the shield 37.

[0101] The busbar unit obtained by the manufacturing method of this embodiment can be specified by the configuration having the above-mentioned multiple types of pin insertion holes. In the manufacturing process of the busbar unit 36, the fourth positioning pin 214, the fifth positioning pin 215, and the sixth positioning pin 216 are used as necessary. A busbar unit obtained by a manufacturing method that does not use one or more of the fourth positioning pin 214, the fifth positioning pin 215, and the sixth positioning pin 216 naturally does not have pin insertion holes corresponding to the unused positioning pins. [Explanation of symbols]

[0102] 1...motor, 1aG, 1aU, 1aV, 1aW, 2aG, 2aU, 2aV, 2aW...busbar main body, 1bG, 1bU, 1bV, 1bW, 2bG, 2bU, 2bV, 2bW...coil wiring section, 1cU, 1cV, 1cW, 2cU, 2cV, 2cW...external power supply wiring section, 1dG, 1dU, 1dv, 1dV, 1dW, 1eG, 1eV, 1eW, 1fW, 2dG, 2dU, 2dV, 2dW, 2eG, 2eV, 2eW, 2fW...wide section, 20...rotor, 30...stator, 31...stator core, 33...coil, 34...busbar group, 35...busbar holder, 35a...inner hole, 36...busbar unit, 37...shield, 37c...seal notch, 37d...shield through hole, 60...rotational position detection unit, 200...mold, 201...upper mold, 202...lower mold, 211...first positioning pin, 212...second positioning pin, 213...third positioning pin, 214...fourth positioning pin, 341U...first U-phase bus bar, 341V...first V-phase bus bar, 341W...first W-phase bus bar, 342U...second U-phase bus bar, 342V...second V-phase bus bar, 342W...second W-phase bus bar, 353...connector portion, H11-H19, H21-H29...busbar through holes, Hp1...first pin insertion hole, Hp2...second pin insertion hole, Hp3...third pin insertion hole, J...center axis, α...range

Claims

1. A method for manufacturing a busbar unit applicable to connecting a coil in a motor to an external power supply, comprising the steps of: the bus bar unit includes a plurality of bus bars each formed of a plate-shaped conductor, a thin plate-shaped shield for blocking magnetic fields generated from the bus bars, and a bus bar holder for holding the bus bars and the shield, each of the plurality of busbars has an arc-shaped busbar main body portion held by the busbar holder with a plate surface facing up or down, a plurality of busbar through holes penetrating the busbar in a plate thickness direction, a coil wiring portion and an external power supply wiring portion respectively extending from different ends of the busbar main body portion, and a wide portion protruding in a width direction from a side surface; the external power supply wiring portions of the plurality of bus bars extend linearly from ends of the bus bar main body portions toward an outer periphery when viewed in a top-bottom direction and are arranged side by side in a width direction of the external power supply wiring portions, Among the plurality of external power supply wiring sections aligned in the width direction, the external power supply wiring section disposed at an end in the direction in which the plurality of external power supply wiring sections are aligned has a first wide portion protruding from a side surface facing an adjacent external power supply wiring section, among the plurality of external power supply wiring parts aligned in the width direction, two of the external power supply wiring parts that are not arranged at an end in the direction in which the plurality of external power supply wiring parts are aligned and that are arranged adjacent to each other in the width direction each have a second wide portion protruding from a side surface facing each other, the second wide portions protruding from the opposing side surfaces overlap each other when viewed from a direction in which the external power supply wiring portion extends; the shield has portions overlapping with the plurality of bus bar through holes when viewed from above and below, The step of manufacturing the busbar unit includes: preparing a mold for insert molding the bus bar and the shield; a first step of positioning the bus bar and the shield within the die; a second step of molding the bus bar holder by injecting resin into the mold after the first step; having The first step comprises: a step of inserting a plurality of first positioning pins extending upward from an upper surface of a lower mold of the die into the plurality of bus bar through holes, thereby holding the bus bar by the first positioning pins; placing the shield in the mold with a bottom surface of the shield in contact with a tip of the first positioning pin; a step of bringing a second positioning pin extending downward from a lower surface of an upper mold of the mold into contact with an upper surface of the shield to position the shield in a vertical direction; a step of bringing a third positioning pin extending downward from a lower surface of the upper mold into contact with an upper surface of the bus bar to position the bus bar in a vertical direction; having A manufacturing method of a busbar unit.

2. A method for manufacturing a busbar unit as described in claim 1, wherein the second wide portion has a plurality of through holes.

3. The shield has a shield through hole penetrating the shield in a plate thickness direction, The mold has a fourth positioning pin extending upward from an upper surface of the lower mold or extending downward from a lower surface of the upper mold, The first step includes a step of inserting the fourth positioning pin into the shield through hole. A method for manufacturing the busbar unit according to claim 1 or 2.

4. The bus bar has the bus bar through hole at each end of the bus bar main body. A method for manufacturing the busbar unit according to claim 1 .

5. the bus bar includes a coil wiring portion and an external power supply wiring portion extending from different ends of the bus bar body, the external power supply wiring portions extend linearly from the ends of the bus bar main body portions toward the outer periphery when viewed in a top-bottom direction, and are arranged side by side in a width direction of the external power supply wiring portions, The bus bar has a bus bar through hole penetrating the external power supply wiring portion in a plate thickness direction. A method for manufacturing the busbar unit according to claim 1 .

6. the bus bar holder is annular and has an inner hole extending in a vertical direction, the bus bar has the bus bar through hole in a range of ±45 degrees from a central position of a connector portion where the plurality of external power supply wiring portions are located in a circumferential direction about a central axis of the inner hole. The method for manufacturing the busbar unit according to claim 5 .

7. The bus bar has a wide portion protruding in a width direction from a side surface of the bus bar. A method for manufacturing the busbar unit according to claim 1 .

8. The bus bar has the bus bar through hole in the wide portion. The method for manufacturing the busbar unit according to claim 7.

9. the bus bar has the wide portion at a portion where the bus bar is bent; A method for manufacturing the busbar unit according to claim 7 or 8.

10. A busbar unit applicable to connecting a coil in a motor to an external power supply, the magnetic field generating circuit includes a plurality of bus bars each made of a plate-shaped conductor, a thin plate-shaped shield for blocking magnetic fields generated from the bus bars, and a bus bar holder for holding the bus bars and the shield, each of the plurality of busbars has an arc-shaped busbar main body portion held by the busbar holder with a plate surface facing up or down, a plurality of busbar through holes penetrating the busbar in a plate thickness direction, a coil wiring portion and an external power supply wiring portion respectively extending from different ends of the busbar main body portion, and a wide portion protruding in a width direction from a side surface; the external power supply wiring portions of the plurality of bus bars extend linearly from ends of the bus bar main body portions toward an outer periphery when viewed in a top-bottom direction and are arranged side by side in a width direction of the external power supply wiring portions, Among the plurality of external power supply wiring sections aligned in the width direction, the external power supply wiring section disposed at an end in the direction in which the plurality of external power supply wiring sections are aligned has a first wide portion protruding from a side surface facing an adjacent external power supply wiring section, among the plurality of external power supply wiring parts aligned in the width direction, two of the external power supply wiring parts that are not arranged at an end in the direction in which the plurality of external power supply wiring parts are aligned and that are arranged adjacent to each other in the width direction each have a second wide portion protruding from a side surface facing each other, the second wide portions protruding from the opposing side surfaces overlap each other when viewed from a direction in which the external power supply wiring portion extends; the shield has portions overlapping with the plurality of bus bar through holes when viewed from above and below, The bus bar holder includes: a plurality of first pin insertion holes that open in a lower surface of the bus bar holder, extend upward, pass through the bus bar through holes, and reach a lower surface of the shield; a second pin insertion hole that opens at an upper surface of the bus bar holder, extends downward, and reaches an upper surface of the shield; a third pin insertion hole that opens at an upper surface of the bus bar holder, extends downward, and reaches an upper surface of the bus bar; having Busbar unit.

11. The plurality of bus bars include a first U-phase bus bar and a second U-phase bus bar constituting a U-phase bus bar group; a first V-phase bus bar and a second V-phase bus bar constituting a V-phase bus bar group; a first W-phase bus bar and a second W-phase bus bar constituting a W-phase bus bar group; Including, The busbar unit according to claim 10.

12. A motor including a rotor rotatable about a central axis extending in a vertical direction, an annular stator positioned radially outward of the rotor, and a rotational position detection unit positioned above the stator and detecting a rotational position of the rotor, The stator includes a stator body having a coil and a stator core, and the busbar unit according to claim 10 or 11, which is located between the stator core and the rotational position detection unit. Motor.

13. A motor including a rotor rotatable about a central axis extending in a vertical direction, an annular stator positioned radially outward of the rotor, and a rotational position detection unit positioned above the stator and detecting a rotational position of the rotor, the stator includes a stator body having a coil and a stator core, and a busbar unit located between the stator core and the rotational position detection unit; the busbar unit includes a plurality of busbars each formed of a plate-shaped conductor, a thin plate-shaped shield for blocking magnetic fields generated from the busbars, and a busbar holder for holding the busbars and the shield; each of the plurality of busbars has an arc-shaped busbar main body portion held by the busbar holder with a plate surface facing up or down, a plurality of busbar through holes penetrating the busbar in a plate thickness direction, a coil wiring portion and an external power supply wiring portion respectively extending from different ends of the busbar main body portion, and a wide portion protruding in a width direction from a side surface; the external power supply wiring portions extend linearly from the ends of the bus bar main body portions toward the outer periphery when viewed in a top-bottom direction, and are arranged side by side in a width direction of the external power supply wiring portions, the external power supply wiring portions of the plurality of bus bars extend linearly from ends of the bus bar main body portions toward an outer periphery when viewed in a top-bottom direction and are arranged side by side in a width direction of the external power supply wiring portions, Among the plurality of external power supply wiring sections aligned in the width direction, the external power supply wiring section disposed at an end in the direction in which the plurality of external power supply wiring sections are aligned has a first wide portion protruding from a side surface facing an adjacent external power supply wiring section, among the plurality of external power supply wiring parts aligned in the width direction, two of the external power supply wiring parts that are not arranged at an end in the direction in which the plurality of external power supply wiring parts are aligned and that are arranged adjacent to each other in the width direction each have a second wide portion protruding from a side surface facing each other, the second wide portions protruding from the opposing side surfaces overlap each other when viewed from a direction in which the external power supply wiring portion extends; the shield has a plurality of through hole shielding portions that overlap with the plurality of bus bar through holes when viewed from above and below, Among the plurality of through hole shielding portions, some of the through hole shielding portions are located in the external power supply wiring portion, and other of the through hole shielding portions are located in the bus bar main body portion or the coil wiring portion. Motor.

14. the bus bar holder is annular and has an inner hole extending in a vertical direction, the through hole shielding portion is located within a range of ±45 degrees from a central position of the connector portion where the plurality of external power supply wiring portions are located in a circumferential direction around a central axis of the inner hole; 14. The motor according to claim 13.

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