Motor device

Abstract

The motor device (11) of the present invention includes a motor (12) and a control device (13) having a base plate (32). The motor has a housing (21), a stator (23), a rotor (25) having an output shaft (25A), a bearing (22D), a bearing cage (22) for holding the bearing, and a busbar module (24). The bearing cage has a thick-walled portion (22A) having a terminal insertion hole that extends axially, and a thin-walled portion (22B) that is thinner axially than the thick-walled portion. The busbar module has a busbar cage (24A) for holding the busbar. The busbar has a motor terminal (24B). The busbar cage has a surrounding portion (24C) that surrounds a portion including the base end of the motor terminal, and the surrounding portion is inserted into the terminal insertion hole in a manner that does not extend axially through the terminal insertion hole. There is a space (SP) around the portion of the motor terminal exposed from the surrounding portion, which is the gap between the inner circumferential surface of the terminal insertion hole and the surface of the motor terminal.

Description

Technical Field

[0001] This invention relates to an electric motor device. Background Technology

[0002] For example, the motor assembly in Patent Document 1 includes a motor, a bearing cage, and a busbar unit. The busbar unit is disposed between the motor and the bearing cage. The busbar unit has multiple busbars and an electrically insulating busbar cage that houses these multiple busbars. The multiple busbars are respectively connected to multiple coils and are respectively inserted into multiple through holes in the bearing cage. The busbar cage has a holding portion for holding multiple terminals. The holding portion has multiple insertion portions that surround the portions of the multiple busbars inserted into the through holes. The multiple insertion portions are respectively inserted into or pressed into the multiple through holes. Contact between the inner surface of the through holes of the bearing cage and the surface of the busbars is avoided by the insertion portions.

[0003] The bearing cage has a thick-walled portion extending in the vertical direction of the motor shaft and a thin-walled portion that is thinner than the thick-walled portion. The thin-walled portion is provided around a plurality of through holes in the bearing cage. The thin-walled portion is formed by providing a recess on the surface of the bearing cage opposite to the busbar unit. The recess opens toward the side opposite to the busbar unit. The thin-walled portion is the thin-walled portion of the bearing cage remaining on the busbar unit side.

[0004] Patent document: JP 2020-099144

[0005] For motor units, it is required to stably support the motor terminals while ensuring the degree of freedom of the motor terminals at the ends, which are part of the busbar. Summary of the Invention

[0006] One aspect of this disclosure relates to an electric motor device comprising an electric motor and a control device having a substrate disposed at an end of the electric motor. The electric motor includes: a housing having an end wall at a first end opposite to the control device; a cylindrical stator having a plurality of windings and embedded in the inner circumferential surface of the housing; a rotor disposed inside the stator and not in contact with the stator, and having an output shaft extending axially through the stator; a bearing rotatably supporting the output shaft; a metal bearing cage mounted at a second end of the housing and holding the bearing; and a busbar module disposed between the stator and the bearing cage. The bearing cage has a thick-walled portion having a terminal through-hole extending axially, and a thin-walled portion with an axial thickness thinner than the thick-walled portion. The busbar module has a plurality of busbars and a resin busbar cage holding the busbars. The busbars have motor terminals that extend axially through the terminal through-hole in a manner not in contact with the inner circumferential surface of the terminal through-hole and are connected to the substrate. The busbar retainer has a surrounding portion that surrounds a portion including the base end of the motor terminal. The surrounding portion is inserted into the terminal insertion hole but does not penetrate the terminal insertion hole axially. A space exists around the portion of the motor terminal exposed from the surrounding portion; this space is the gap between the inner circumferential surface of the terminal insertion hole and the surface of the motor terminal. Attached Figure Description

[0007] Figure 1 This is a cross-sectional view of an embodiment of the motor device, cut along the axial direction.

[0008] Figure 2 It means Figure 1 A cross-sectional view of the main parts of the motor unit.

[0009] Figure 3 It means Figure 1 A sectional view of the main parts of the motor assembly in its first mounting position.

[0010] Figure 4 It means Figure 1 A sectional view of the main part of the motor assembly in the second mounting position.

[0011] Figure 5 It means Figure 1 A sectional view of the main part of the motor unit in the third mounting position.

[0012] Figure 6 It means Figure 1 A cross-sectional view of the main parts of the motor unit.

[0013] Figure 7 It means Figure 1 A cross-sectional view of the main parts of the motor unit. Detailed Implementation

[0014] The following describes a motor device according to one embodiment. Figure 1 As shown, the motor assembly 11 includes a motor 12 and a control device 13. The motor 12 is, for example, a three-phase brushless motor. The control device 13 is located at the axial end of the motor 12. The control device 13 controls the drive of the motor 12.

[0015] <Motor 12> First, the structure of motor 12 will be described. Motor 12 has a housing 21, a bearing cage 22, a stator 23, a busbar module 24, and a rotor 25.

[0016] The housing 21 has: a peripheral wall with a circular cross-sectional shape and an end wall that closes a first end of the peripheral wall. A second end of the peripheral wall is open to the outside. The second end is the end of the peripheral wall opposite to the first end. The first end of the peripheral wall is also the first end of the housing 21. The second end of the peripheral wall is also the second end of the housing 21. The housing 21 has a first bearing support portion 21A. The first bearing support portion 21A is disposed on the end wall of the housing 21. The first bearing support portion 21A is a spatial portion with a circular cross-sectional shape, connecting the interior and exterior of the housing 21. A first bearing 21B is installed in the first bearing support portion 21A.

[0017] The bearing cage 22 is mounted on the second end of the housing 21. The bearing cage 22 is embedded inside the second end of the housing 21. The bearing cage 22 has a thick-walled portion 22A, a thin-walled portion 22B, and a second bearing support portion 22C.

[0018] In the axial direction of the motor 12, the thick-walled portion 22A is thicker than the thin-walled portion 22B. The thick-walled portion 22A protrudes in the direction opposite to the stator 23 relative to the thin-walled portion 22B. That is, the outer surface of the thick-walled portion 22A is located further outward in the axial direction than the outer surface of the thin-walled portion 22B. The outer surface is the side of the thick-walled portion 22A and the thin-walled portion 22B facing from the first end of the housing 21 toward the second end. The outer side is the side of the housing 21 facing from the first end to the second end. The second bearing support portion 22C is provided on the inner surface of the bearing cage 22. The inner surface is the side of the bearing cage 22 facing from the second end of the housing 21 toward the first end.

[0019] The second bearing support portion 22C is a spatial portion with a circular cross-section, and openings on both the inner and outer surfaces of the bearing cage 22. The second bearing support portion 22C is coaxially configured with the first bearing support portion 21A. A second bearing 22D is mounted in the second bearing support portion 22C. The bearing cage 22 is made of, for example, a metal with excellent thermal conductivity such as aluminum. The bearing cage 22 also functions as a heat sink to promote heat dissipation.

[0020] The stator 23 is embedded in the inner circumferential surface of the housing 21. The stator 23 has a stator core 23A, a first insulator 23B, a second insulator 23C, multiple windings 23D, and a stator retaining member 23E. The stator core 23A is a cylindrical body with a circular cross-sectional shape. The first insulator 23B is disposed at a first end of the stator core 23A. The second insulator 23C is disposed at a second end of the stator core 23A. The windings 23D are wound around the stator core 23A via the first insulator 23B and the second insulator 23C. The stator retaining member 23E is a cylindrical body with a circular cross-sectional shape. The inner circumferential surface of the stator retaining member 23E is mounted on the outer circumferential surface of the stator core 23A. The stator 23 is supported inside the housing 21 by the stator retaining member 23E.

[0021] Busbar module 24 is disposed between bearing cage 22 and stator 23. Busbar module 24 is located at the end of stator 23. This end is the end of stator 23 on the bearing cage 22 side. Busbar module 24 has multiple metal busbars and resin busbar cage 24A. Busbar cage 24A is a cylindrical body with a circular cross-section. The portion of bearing cage 22 in which the second bearing support 22C is provided is inserted into the interior of busbar cage 24A in a non-contact manner. The axial position of bearing cage 22 overlaps with the axial position of second bearing 22D. Each busbar is formed by plastically deforming a metal sheet stamped into a predetermined shape. Each busbar is held by busbar cage 24A. Each busbar corresponds to one of the three phases. Each busbar is connected to the end of the winding 23E of the corresponding phase of the three phases.

[0022] Each busbar has a motor terminal 24B. Each motor terminal 24B is part of each busbar and is disposed on the periphery of the bearing cage 22. Furthermore, each motor terminal 24B is positioned radially outward from the outer peripheral surface of the stator 23. Each motor terminal 24B extends axially along the motor 12, protruding from the outer surface of the busbar cage 24A towards the outside of the busbar cage 24A. The outer surface is the axially opposite surface of the busbar cage 24A to the bearing cage 22. The outer side is the side of the busbar cage 24A facing the bearing cage 22. Although not shown in the figure, the motor terminals 24B are arranged in a row when viewed from a direction orthogonal to the axial direction of the motor 12. The ends of each motor terminal 24B penetrate axially through the periphery of the bearing cage 22 in a manner that does not contact the bearing cage 22 (specifically, the thick-walled portion 22A). Three-phase AC power is supplied to each of the three-phase windings 23D via each busbar. Detailed descriptions of the support structures for each motor terminal 24B will be provided later.

[0023] The rotor 25 has an output shaft 25A, a rotor core 25B, and a rotor magnet 25C. The output shaft 25A is rotatably supported via a first bearing 21B and a second bearing 22D. A first end of the output shaft 25A extends through the end wall of the housing 21 and protrudes outward without contacting it. A second end of the output shaft 25A extends toward the control device 13. The rotor core 25B is a cylindrical body with a circular cross-section and is mounted on the outer peripheral surface of the output shaft 25. The rotor magnet 25C is, for example, a cylindrical body with a circular cross-section and is mounted on the outer peripheral surface of the rotor core 25B. The rotor core 25B and the rotor magnet 25C are disposed inside the stator core 23A. A small gap is formed between the outer peripheral surface of the rotor magnet 25C and the inner peripheral surface of the stator core 23A.

[0024] <Control Device 13> Next, the structure of the control device 13 will be described. The control device 13 includes a control board 31, a power board 32, and a cover 33.

[0025] The control board 31 has electronic components for controlling the supply of power to the motor 12. The control board 31 is arranged to cover the outer surface of the thin-walled portion 22B of the bearing cage 22. The power board 32 has electronic components for supplying power to the motor 12 under the control of the control board 31. The power board 32 is located further outward in the axial direction than the control board 31. That is, in the axial direction of the motor 12, the power board 32 is further away from the stator 23 than the control board 31. The power board 32 is arranged to cover the outer surface of the thick-walled portion 22A of the control board 31 and the bearing cage 22. The ends of each motor terminal 24B pass through the power board 32 axially and are connected to the power board 32 by soldering.

[0026] The cover 33 is made of synthetic resin. The cover 33 is a box-shaped body with an opening facing the motor 12. The cover 33 is mounted on the second end of the housing 21. The cover 33 covers the second end of the housing 21.

[0027] The cover 33 has a power connector 33A. The power connector 33A extends in the direction opposite to the motor 12. The power connector 33A has a power terminal and a ground terminal. The power terminal and the ground terminal are connected to the power board 32 by soldering. A power plug, as a mating connector, is fitted into the power connector 33A. The power plug is connected to a DC power source such as a battery via a power cord. The DC power is supplied to the control board 31 and the power board 32 via the power terminal and the ground terminal.

[0028] The cover 33 has a signal connector 33B. The signal connector 33B extends in the opposite direction to the motor 12. The signal connector 33B has signal terminals. A signal plug, as a mating connector, engages with the signal connector 33B. The signal plug is connected to the upper control device via a signal line. The control board 31 and the upper control device transmit and receive signals via the signal terminals.

[0029] <Support Structure for Motor Terminal 24B> Next, the support structure for motor terminal 24B will be described. For example... Figure 2 As shown, the bearing cage 22 has a terminal insertion hole 22E. The terminal insertion hole 22E is provided in the thick-walled portion 22A. The terminal insertion hole 22E extends axially through the thick-walled portion 22A. The terminal insertion hole 22E is, for example, a stepped hole with a rectangular cross-section. The terminal insertion hole 22E allows three motor terminals 24B arranged in a row to pass through.

[0030] The terminal insertion hole 22E has a first hole portion 22E1 and a second hole portion 22E2. In the radial direction of the motor 12, the length of the first hole portion 22E1 is longer than the length of the second hole portion 22E2. The first hole portion 22E1 opens on the outer surface of the thick-walled portion 22A. A first stepped portion 22E3 is formed between the first hole portion 22E1 and the second hole portion 22E2. The first stepped portion 22E3 is a plane extending in the radial direction of the motor 12, i.e., in a direction orthogonal to the axial direction of the motor 12.

[0031] Busbar retainer 24A has a surrounding portion 24C. The surrounding portion 24C is the part of the busbar retainer 24A into which the terminal insertion holes 22E are inserted, and it also surrounds the base end portion including each motor terminal 24B. The base end is the end opposite to the end of the motor terminal 24B, and is the starting point from which the busbar retainer 24A rises towards the bearing retainer 22 from its outer surface. The portion including the base end of each motor terminal 24B is covered and held by the surrounding portion 24C. The surrounding portion 24C is, for example, a stepped columnar body with a rectangular cross-section.

[0032] The enclosure portion 24C has a first insertion portion 24C1 and a second insertion portion 24C2. The first insertion portion 24C1 is further away from the outer surface of the busbar holder 24A than the second insertion portion 24C2. In the radial direction of the motor 12, the length of the first insertion portion 24C1 is shorter than the length of the second insertion portion 24C2. A second stepped portion 24C3 is formed between the first insertion portion 24C1 and the second insertion portion 24C2. The second stepped portion 24C3 is a plane extending in the radial direction of the motor 12, that is, in a direction orthogonal to the axial direction of the motor 12. The enclosure portion 24C is a two-stage columnar body.

[0033] The first insertion part 24C1 is inserted into the first hole 22E1. However, the end of the first insertion part 24C1 is located inside the first hole 22E1. That is, the end of the first insertion part 24C1 does not penetrate the first hole 22E1 axially. A first gap is formed between the outer peripheral surface of the first insertion part 24C1 and the inner peripheral surface of the first hole 22E1. The second insertion part 24C2 is inserted into the second hole 22E2. A second gap is formed between the outer peripheral surface of the second insertion part 24C2 and the inner peripheral surface of the second hole 22E2. The second gap is wider than the first gap. The second stepped surface 24C3 is axially opposite to the first stepped surface 22E3.

[0034] Viewed from a direction orthogonal to the axis of the motor 12, a crank-shaped gap is formed between the outer peripheral surface of the enclosure 24C and the inner peripheral surface of the terminal insertion hole 22E. The crank shape is formed by alternating right-angle bends. The inner peripheral surface of the first hole 22E1, the first stepped portion 22E3, the outer peripheral surface of the first insertion portion 24C1, and the second stepped portion 24C3 form the first corner of the crank-shaped gap. The inner peripheral surface of the first stepped portion 22E3, the inner peripheral surface of the second hole 22E2, the second stepped portion 24C3, and the outer peripheral surface of the second insertion portion 24C2 form the second corner of the crank-shaped gap. The first and second corners correspond to the right-angle bends of the crank.

[0035] A third gap is formed between the outer peripheral surface of the portion of motor terminal 24B protruding from the enclosure 24C and the inner peripheral surface of the first hole 22E1. This third gap is wider than the first gap between the outer peripheral surface of the first insertion portion 24C1 and the inner peripheral surface of the first hole 22E1. Furthermore, the third gap is wider than the second gap between the outer peripheral surface of the second insertion portion 24C2 and the inner peripheral surface of the second hole 22E2. This third gap is the space SP surrounding the portion of motor terminal 24B exposed from the enclosure 24C.

[0036] <Function of this Embodiment> Next, the function of this embodiment will be explained. For example... Figure 2 As shown, the terminal insertion hole 22E has a first stepped portion 22E3. The surrounding portion 24C has a second stepped portion 24C3. The first stepped portion 22E3 and the second stepped portion 24C3 are opposite to each other in the axial direction of the motor 12. Therefore, the crank-shaped gap between the outer peripheral surface of the surrounding portion 24C and the inner peripheral surface of the terminal insertion hole 22E acts as a labyrinth structure.

[0037] like Figure 3 As shown, foreign matter FO1 may be generated inside the motor 12. Foreign matter FO1 includes, for example, dust, metal powder, resin powder, and splatter from the connection between the busbar and winding 23D. However, the crank-shaped gap acts as a labyrinth structure. Therefore, foreign matter FO1 generated inside the motor 12 has difficulty passing through the crank-shaped gap. This prevents foreign matter generated inside the motor 12 from intruding into the control device 13.

[0038] In addition, such as Figure 2 As shown, the engagement length L1 between the surrounding portion 24C and the terminal insertion hole 22E is ensured. The engagement length L1 is, for example, approximately half the total length L2 of the terminal insertion hole 22E, and is within an allowable range based on half the total length L2 of the terminal insertion hole 22E. The allowable range is set through experiments or simulations. Therefore, the length of the crank-shaped clearance is ensured in the axial direction of the motor 12. Therefore, regardless of the posture in which the motor assembly 11 is mounted on the mounting object, it is possible to prevent foreign matter FO1 generated inside the motor 12 from intruding into the control device 13.

[0039] The motor assembly 11 can be installed in various positions, such as a first mounting position, a second mounting position, and a third mounting position. Figure 3 As shown, the first mounting posture is that the surrounding part 24C faces upward (upward in the direction of gravity) towards the motor device 11. Figure 4 As shown, the second mounting posture is the posture in which the surrounding part 24C faces downward (downward in the direction of gravity) towards the motor device 11. Figure 5 As shown, the third mounting posture is the posture in which the surrounding part 24C faces the motor device 11 in a direction orthogonal to the direction of gravity. Regardless of whether the motor device 11 is mounted on the mounting object in the first, second, or third mounting posture, it is possible to prevent foreign matter FO1 from entering the control device 13 from inside the motor 12.

[0040] like Figure 6 As shown, the busbar module 24 may be tilted relative to the axial direction of the motor 12. However, the engagement length L1 between the surrounding portion 24C and the terminal insertion hole 22E is set such that when the busbar module 24 is tilted relative to the axial direction of the motor 12, the surrounding portion 24C contacts the inner peripheral surface of the terminal insertion hole 22E before the motor terminal 24B. Therefore, when the busbar module 24 is tilted relative to the axial direction of the motor 12, the surrounding portion 24C contacts the inner peripheral surface of the terminal insertion hole 22E before the motor terminal 24B. Specifically, the end corner of the first insertion portion 24C1 in the surrounding portion 24C contacts the inner peripheral surface of the first hole portion 22E1. This prevents the motor terminal 24B from contacting the inner peripheral surface of the terminal insertion hole 22E.

[0041] Terminal insertion hole 22E is provided in the thick-walled portion 22A of bearing cage 22. The thick-walled portion 22A has higher rigidity than the thin-walled portion 22B. Therefore, when busbar module 24 is axially tilted relative to motor 12 and the surrounding portion 24C contacts the inner peripheral surface of terminal insertion hole 22E, the surrounding portion 24C is stably supported by the inner peripheral surface of terminal insertion hole 22E.

[0042] Furthermore, when the busbar module 24 is tilted relative to the motor 12 axially, the longer the engagement length L1, the smaller the tilt of the motor terminal 24B. However, the longer the engagement length L1, the less of the motor terminal 24B is exposed from the enclosure 24C. Therefore, if the engagement length L1 is too long, the portion of the motor terminal 24B exposed from the enclosure 24C becomes difficult to bend. If the motor terminal 24B is difficult to bend, it may be difficult to insert the end of the motor terminal 24B into the motor terminal connection portion 32A of the power board 32 when assembling the motor device 11. The motor terminal connection portion 32A is a hole that penetrates the power board 32 along the thickness direction and is provided corresponding to each motor terminal 24B.

[0043] Therefore, in this embodiment, in order to ensure the flexibility of the portion of the motor terminal 24B exposed from the surrounding portion 24C, the engagement length L1 is set to approximately half of the total length L2 of the terminal insertion hole 22E. Therefore, when assembling the motor assembly 11, it is easy to insert the end of the motor terminal 24B into the motor terminal connection portion 32A of the power board 32.

[0044] Furthermore, a space SP exists around the portion of the motor terminal 24B exposed from the enclosure 24C. The space SP is the gap between the inner circumferential surface of the first hole 22E1 in the terminal insertion hole 22E and the surface of the motor terminal 24B. The presence of the space SP allows the portion of the motor terminal 24B exposed from the enclosure 24C to bend. That is, the flexibility of the portion of the motor terminal 24B exposed from the enclosure 24C is ensured.

[0045] like Figure 7 As shown, foreign matter FO2 may be generated inside the control device 13. Foreign matter FO2 includes, for example, dust and solder that has detached from the power board 32. However, a portion of the foreign matter FO2 remains inside the space SP. Therefore, the presence of the space SP prevents foreign matter FO2 from intruding from the control device 13 into the motor 12.

[0046] Furthermore, the crank-shaped gap between the outer peripheral surface of the surround portion 24C and the inner peripheral surface of the terminal insertion hole 22E acts as a labyrinth structure. Therefore, foreign objects FO2 generated inside the control device 13 have difficulty passing through the crank-shaped gap. This prevents foreign objects generated inside the control device 13 from entering the motor 12.

[0047] <Effects of the Embodiment> This embodiment has the following effects. (1) The busbar holder 24A has a surrounding portion 24C that surrounds the portion including the base end of the motor terminal 24B. The surrounding portion 24C is inserted into the terminal insertion hole 22E in such a way that it does not penetrate axially through the terminal insertion hole 22E provided in the thick-walled portion 22A. There is a space SP around the portion of the motor terminal 24B that is exposed from the surrounding portion 24C. The space SP is the gap between the inner peripheral surface of the terminal insertion hole 22E and the surface of the motor terminal 24B. According to this structure, the surrounding portion 24C is inserted into the terminal insertion hole 22E provided in the thick-walled portion 22A. The thick-walled portion 22A has higher rigidity than the thin-walled portion 22B. Therefore, the motor terminal 24B can be stably supported. In addition, there is a space SP around the portion of the motor terminal 24B that is exposed from the surrounding portion 24C. Since the degree of freedom of the end of the motor terminal 24B can be ensured, it is easy to connect the motor terminal 24B to the power board 32.

[0048] (2) The terminal insertion hole 22E has a first stepped portion 22E3. The surrounding portion 24 has a second stepped portion 24C3. The first stepped portion 22E3 and the second stepped portion 24C3 are opposite to each other in the axial direction of the motor 12. According to this structure, a crank-shaped gap is formed between the outer peripheral surface of the surrounding portion 24C and the inner peripheral surface of the terminal insertion hole 22E. The crank-shaped gap acts as a labyrinth structure. Therefore, foreign matter FO1 generated inside the motor 12 is difficult to pass through the crank-shaped gap. Thus, it is possible to suppress foreign matter generated inside the motor 12 from entering the control device 13. In addition, foreign matter FO2 generated inside the control device 13 is also difficult to pass through the crank-shaped gap. Therefore, it is possible to suppress foreign matter FO2 generated inside the control device 13 from entering the motor 12.

[0049] (3) The motor terminal 24B is located radially outward from the outer peripheral surface of the stator 23. As shown in this structure, depending on the product specifications, the motor terminal 24B is sometimes located radially outward from the outer peripheral surface of the stator 23.

[0050] (4) The thick-walled portion 22A protrudes in the opposite direction to the stator 23 relative to the thin-walled portion 22B. According to this structure, the axial length of the motor device 11 can be shortened compared to the case where the thick-walled portion 22A is thicker than the thin-walled portion 22B in the direction toward the stator 23.

[0051] (5) The busbar retainer 24A is a cylindrical body with a circular cross-section. The portion of the bearing retainer 22 that holds the second bearing 22D (i.e., the second bearing support portion 22C) is inserted into the busbar retainer 24A in a non-contact manner. As a result, the axial position of the second bearing 22D overlaps with the axial position of the busbar retainer 24A. With this structure, the internal space of the busbar retainer 24A, which is a dead space, can be effectively utilized. Furthermore, since the axial position of the second bearing 22D overlaps with the axial position of the busbar retainer 24A, the axial length of the motor assembly 11 can be shortened.

[0052] (6) The engagement length L1 of the surrounding portion 24C and the terminal insertion hole 22E is within the allowable range based on half of the total length L2 of the terminal insertion hole 22E. According to this structure, the motor terminal 24B can be stably supported while ensuring the degree of freedom of the end of the motor terminal 24B.

[0053] (7) The engagement length L1 between the surrounding portion 24C and the terminal insertion hole 22E is set such that when the busbar module 24 is axially inclined relative to the motor 12, the surrounding portion 24C contacts the inner peripheral surface of the terminal insertion hole 22E before the motor terminal 24B. Therefore, the contact between the motor terminal 24B and the inner peripheral surface of the terminal insertion hole 22E is suppressed.

[0054] (8) As a support structure for the motor terminal 24B, a rubber bushing fitted into the terminal insertion hole 22E can be considered to support the motor terminal 24B. In this case, a separate rubber bushing is required. According to this embodiment, the surrounding portion 24C supporting the motor terminal 24B is integrally formed with the busbar retainer 24A. Therefore, the motor terminal 24B can be stably supported without adding a rubber bushing. Therefore, it is possible to suppress the increase in assembly steps of the motor device 11 or the increase in product cost.

[0055] <Other Implementation Methods> This implementation method can also be implemented with the following modifications.

[0056] Winding 23D can also form a first winding group and a second winding group. When the winding 23D of motor 12 forms two winding groups, the power supply to the two winding groups by control device 13 is controlled independently for each group. Two sets of three-phase motor terminals 24B are provided.

Claims

1. An electric motor device comprising an electric motor and a control device having a base plate disposed at an end of the electric motor, the electric motor comprising: a housing having an end wall at a first end opposite to the control device; a cylindrical stator having a plurality of windings and embedded in the inner circumferential surface of the housing; a rotor disposed inside the stator and not in contact with the stator, and having an output shaft extending axially through the stator; a bearing rotatably supporting the output shaft; a metal bearing cage mounted at a second end of the housing and holding the bearing; and a busbar module disposed between the stator and the bearing cage, the bearing cage having a thick-walled portion having a terminal through-hole extending axially, and an axial... The busbar module has a thinner wall portion than the thick-walled portion, and includes a plurality of busbars and a resin busbar holder for holding the busbars. The busbars have motor terminals that pass through the terminal insertion holes axially without contacting the inner circumferential surface of the terminal insertion holes and are connected to the substrate. The busbar holder has a surrounding portion that surrounds a portion including the base end of the motor terminal. The surrounding portion is inserted into the terminal insertion hole without passing through it axially. There is a space around the portion of the motor terminal exposed from the surrounding portion, which is the gap between the inner circumferential surface of the terminal insertion hole and the surface of the motor terminal.

2. The electric machine device of claim 1, wherein, The terminal insertion hole and the surrounding portion each have stepped portions that are axially opposite to each other.

3. The electric machine device of claim 1 or 2, wherein, The motor terminals are located radially outward from the outer periphery of the stator.

4. The electric machine device of claim 1 or 2, wherein, The thick-walled portion protrudes in the opposite direction to the stator relative to the thin-walled portion.

5. The electric machine device of claim 1 or 2, wherein, The busbar retainer is a cylindrical body with a circular cross-section. The portion of the bearing retainer that holds the bearing is inserted into the busbar retainer in a non-contact manner, thereby aligning the axial position of the bearing with the axial position of the busbar retainer.

6. The electric machine device of claim 1 or 2, wherein, The engagement length between the surrounding portion and the terminal insertion hole is within an allowable range based on half the total length of the terminal insertion hole.

7. The electric machine device of claim 1 or 2, wherein, The engagement length between the surrounding portion and the terminal insertion hole is set such that when the busbar module is tilted relative to the axial direction of the motor, the surrounding portion contacts the inner circumferential surface of the terminal insertion hole before the motor terminal.

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