Drive device

Abstract

A drive device according to one embodiment of the present invention is provided with a rotor, a stator, a housing, a bearing, and a bearing holder that is positioned on one side of the stator in the axial direction and holds the bearing. The housing has a tubular inner tube section and an outer tube section centered on the central axis. A flow path portion is provided between the inner cylinder portion and the outer cylinder portion. The bearing holder is provided with: a main body part having a circular plate shape centered on a central axis; a bearing holding part for holding the bearing; a first fastening part fixed to the inner cylinder part; and a protruding portion protruding from the other side of the body portion in the axial direction from a surface facing the other side of the body portion in the axial direction. The protruding portion extends in the circumferential direction along an imaginary circle centered on the central axis when viewed from the axial direction, and is fitted into the inner circumferential surface of the inner tube portion. The main body portion is provided with a first through hole through which a lead wire extending from a coil of the stator passes. The first through hole is disposed on an imaginary circle when viewed from the axial direction.

Description

Technical Field

[0001] The present invention relates to a drive device.

[0002] This application claims priority based on Japanese Patent Application No. 2022-157698 filed in Japan on September 30, 2022, the contents of which are cited here. Background Art

[0003] As interest in electric vehicles has increased in recent years, various methods for cooling motors have been developed. As an example of a method for cooling a motor, a structure is known in which a water jacket surrounds the outer circumference of a stator to uniformly cool the stator. In such a structure, generally speaking, a bearing retainer that supports the bearing is fixed to the water jacket. For example, a protrusion provided on a bracket (bearing retainer) is inserted into a recessed portion of an end face of a cylindrical frame (water jacket) provided with a refrigerant passage, thereby positioning the bracket relative to the frame (for example, Patent Document 1).

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2012-228105 Summary of the invention

[0007] Problems to be solved by the invention

[0008] In the conventional structure, in order to provide the recessed portion on the end surface of the water jacket, it is necessary to ensure a sufficient thickness of the water jacket, which may lead to an increase in the size of the drive device.

[0009] In view of the above circumstances, one object of the present invention is to provide a driving device that can be reduced in size.

[0010] Means for solving problems

[0011] A driving device according to one embodiment of the present invention comprises: a rotor that can rotate around a central axis; a stator that surrounds the rotor from the radially outer side; a housing that surrounds the stator from the radially outer side and holds the stator; a bearing that supports the rotor so that it can rotate; and a bearing holder that is located on one side of the axial direction of the stator and holds the bearing. The housing comprises an inner cylindrical portion and an outer cylindrical portion that are cylindrical and centered on the central axis. A flow path portion is provided between the inner cylindrical portion and the outer cylindrical portion. The bearing holder comprises: a main body portion that is in the shape of a disk centered on the central axis; a bearing holding portion that holds the bearing; a first fastening portion that is fixed to the inner cylindrical portion; and a protrusion that protrudes from a surface of the main body portion that faces the other axial side to the other axial side. When viewed from the axial direction, the protrusion extends circumferentially along an imaginary circle centered on the central axis, and the protrusion is embedded in the inner circumferential surface of the inner cylindrical portion. A first through hole for passing a lead wire extending from a coil of the stator is provided in the main body portion. When viewed in the axial direction, the first through hole is arranged on the imaginary circle.

[0012] Effects of the Invention

[0013] According to one aspect of the present invention, it is possible to provide a driving device that can be reduced in size. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a conceptual diagram of the driving device according to the first embodiment.

[0015] Figure 2 It is a partial cross-sectional view of the driving device according to the first embodiment.

[0016] Figure 3 This is a front view of the bearing holder mounted on the drive device according to the first embodiment.

[0017] Figure 4 It is a perspective view of the bearing holder according to the first embodiment.

[0018] Figure 5 It is a partial perspective view of a protrusion of a modified example.

[0019] Figure 6 This is a front view of a bearing holder mounted on a drive device according to a second embodiment.

[0020] Figure 7 It is a perspective view of a bearing holder according to a second embodiment. DETAILED DESCRIPTION

[0021] In the following description, the gravity direction is defined and each part is described based on the positional relationship when the drive device 1 is mounted on a vehicle located on a horizontal road surface. In addition, in the drawings, an XYZ coordinate system is appropriately shown as a three-dimensional orthogonal coordinate system.

[0022] In the XYZ coordinate system, the Z-axis direction indicates the vertical direction (i.e., the up-down direction), the +Z direction is the upper side (the opposite side of the gravity direction), and the -Z direction is the lower side (the gravity direction). In addition, the X-axis direction is a direction perpendicular to the Z-axis direction, indicating the front-back direction of the vehicle equipped with the drive device 1. The Y-axis direction is a direction perpendicular to both the X-axis direction and the Z-axis direction, indicating the width direction (left-right direction) of the vehicle.

[0023] In the following description, unless otherwise specified, the direction parallel to the central axis J1 of the motor 2 (Y-axis direction) is referred to as the "axial direction", the radial direction centered on the central axis J1 is referred to as the "radial direction", and the circumferential direction centered on the central axis J1, that is, the direction around the central axis J1 is referred to as the "circumferential direction". However, the above-mentioned "parallel direction" also includes a substantially parallel direction. In addition, in the following description, the +Y direction in the axial direction of the central axis J1 is sometimes referred to as the axial one side, and the -Y direction is sometimes referred to as the axial other side.

[0024] <First embodiment>

[0025] <Drive device>

[0026] Figure 1 This is a conceptual diagram of the driving device 1 according to the first embodiment. Figure 2 It is a partial cross-sectional view of the driving device 1 according to the first embodiment.

[0027] The drive device 1 of the present embodiment is mounted on a vehicle using a motor as a power source, such as a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHV), or an electric vehicle (EV), and is used as the power source thereof.

[0028] like Figure 1 As shown, the drive device 1 includes a motor 2, a power transmission unit 4, an inverter (control unit) 7, a temperature sensor 81, a rotary transformer 29, a bearing holder 70, a housing 6, and a plurality of bearings 5A, 5B, and 5C. The housing 6 accommodates the motor 2, the power transmission unit 4, the inverter 7, the rotary transformer 29, the temperature sensor 81, and the bearing holder 70. The motor 2, the power transmission unit 4, and the inverter 7 are arranged on the central axis J1 inside the housing 6.

[0029] <Motor>

[0030] The motor 2 of this embodiment is an inner rotor type three-phase AC motor. The motor 2 has both the function of an electric motor and the function of a generator. In addition, the structure of the motor 2 is not limited to this embodiment, and for example, it can also be an AC motor with four or more phases.

[0031] The motor 2 includes a rotor 20 that is rotatable about a central axis J1 extending in the horizontal direction, and a stator 30 that is opposed to the rotor 20 with a gap therebetween. That is, the drive device 1 includes the rotor 20 and the stator 30. The motor 2 of this embodiment is an inner rotor type motor in which the rotor 20 is arranged inside the stator 30.

[0032] The rotor 20 includes a first shaft 21 , a rotor core 24 fixed to the outer peripheral surface of the first shaft 21 , a rotor magnet (not shown) fixed to the rotor core 24 , and a pair of fans 10A and 10B. The torque of the rotor 20 is transmitted to the power transmission unit 4 .

[0033] like Figure 2 As shown, the rotor core 24 is provided with a shaft insertion hole 24h and a plurality of air supply holes 24a, 24b. The shaft insertion hole 24h and the air supply holes 24a, 24b penetrate the rotor core 24 in the axial direction. The shaft insertion hole 24h and the air supply holes 24a, 24b are open at both end surfaces in the axial direction of the rotor core 24. The shaft insertion hole 24h extends in the axial direction with the central axis as the center. The first shaft 21 is inserted into the shaft insertion hole 24h.

[0034] A plurality of air supply holes 24a, 24b are arranged along the circumferential direction. The air supply holes 24a, 24b include a first air supply hole 24a and a second air supply hole 24b. The first air supply hole 24a and the second air supply hole 24b are alternately arranged along the circumferential direction. In the rotor 20 of the present embodiment, four first air supply holes 24a and four second air supply holes 24b are provided. The cross-sectional shapes of the first air supply hole 24a and the second air supply hole 24b are equal to each other. The flow directions of the air flowing inside the first air supply hole 24a and the second air supply hole 24b are different from each other.

[0035] The first shaft 21 extends axially with the central axis J1 as the center. The first shaft 21 is supported by bearings 5A and 5B so as to be rotatable. In the following description, one of the pair of bearings 5A and 5B supporting the first shaft 21, which is located on one axial side (+Y side), is sometimes referred to as the first bearing 5A, and the other one located on the other axial side (-Y side) is sometimes referred to as the second bearing 5B.

[0036] A resolver rotor 29a is fixed to an end portion on one axial side (+Y side) of the first shaft 21. In the present embodiment, the resolver rotor 29a is located on one axial side (+Y side) relative to the bearing 5A.

[0037] The pair of fans 10A and 10B are respectively fixed to the end surfaces on one side and the other side of the rotor core 24 in the axial direction. The pair of fans 10A and 10B rotate together with the rotor 20. The pair of fans 10A and 10B are mounted at different positions and directions relative to the rotor 20.

[0038] The pair of fans 10A and 10B allow air to flow through the air supply holes 24a and 24b and blow the air radially outward as the rotor 20 rotates. The air blown out from the fans 10A and 10B contacts the coil ends 31a and 31b arranged radially outward of the fans 10A and 10B. The fans 10A and 10B cool the rotor 20 and the coil ends 31a and 31b.

[0039] like Figure 1 As shown, the stator 30 is held by the housing 6. The stator 30 surrounds the rotor 20 from the radially outer side. The stator 30 includes an annular stator core 32 centered on the central axis J1, a coil 31 mounted on the stator core 32, a lead wire 31k led out from the coil 31, and an insulator (not shown) interposed between the stator core 32 and the coil 31.

[0040] The stator core 32 has an annular core back 32a and a plurality of teeth 32b extending radially inward from the core back 32a. The plurality of teeth 32b are arranged circumferentially. Coil wires are arranged between the teeth 32b arranged circumferentially. The coil wires between adjacent teeth 32b constitute the coil 31. That is, the coil 31 is arranged on the stator core 32. The insulator is made of an insulating material.

[0041] The coil 31 has a pair of coil ends 31a, 31b protruding axially from the end faces on both sides of the stator core 32. The coil ends 31a, 31b are formed by bundling a portion of the coil wire that connects the slots of the stator core 32. In the following description, when distinguishing a pair of coil ends 31a, 31b, the one on one axial side (+Y side) is referred to as the first coil end 31a, and the other on the other axial side (-Y side) is referred to as the second coil end 31b. That is, the stator 30 has the first coil end 31a located at the end on one axial side and the second coil end 31b located at the end on the other axial side.

[0042] The lead wire 31k extends from the coil 31 to one side (+Y side) in the axial direction. The stator 30 of this embodiment has three lead wires 31k corresponding to the U phase, the V phase, and the W phase. The lead wire 31k has a twisted conductor, a crimping terminal crimped to the front end of the conductor, and an insulating tube (not shown) covering the outer periphery of the coil wire. The lead wire 31k is connected to the lead wire connecting portion 7a of the bus bar 7b at the crimping terminal at the front end.

[0043] <Resolver>

[0044] The resolver 29 includes a resolver rotor 29a and a resolver stator (rotation sensor) 29b. The resolver rotor 29a includes a plurality of magnets arranged in the circumferential direction. The resolver rotor 29a rotates around the central axis J1 together with the rotor 20.

[0045] The rotary transformer stator 29b is fixed to the bearing holder 70. The rotary transformer stator 29b surrounds the rotary transformer rotor 29a from the radial outside. The rotary transformer stator 29b has a coil that is excited by the change in magnetic flux accompanying the rotation of the rotary transformer rotor 29a. The rotary transformer stator 29b detects the rotation angle of the rotor 20 based on the change in the excited magnetic flux. The rotary transformer stator 29b has a rotary transformer wiring 29c. The rotary transformer wiring 29c connects the rotary transformer stator 29b and the inverter 7. The rotary transformer wiring 29c supplies power to the rotary transformer stator 29b from the inverter 7. The rotary transformer wiring 29c outputs the result of the rotary transformer 29 detecting the rotation angle of the rotor 20 to the inverter 7.

[0046] <Temperature sensor>

[0047] The temperature sensor 81 is attached to the coil 31 of the stator 30 and measures the temperature of the coil 31. The temperature sensor 81 has a temperature sensor wiring 81a. The temperature sensor wiring 81a is connected to the inverter 7. The temperature sensor wiring 81a outputs the measurement result of the coil temperature by the temperature sensor 81 to the inverter 7.

[0048] <Inverter>

[0049] Figure 1 The inverter 7 shown is electrically connected to the motor 2. The inverter 7 is connected to a battery (not shown) mounted on the vehicle, converts the DC current supplied from the battery into AC current, and supplies it to the motor 2. In addition, the inverter 7 controls the motor 2 based on instructions from an external device and detection results of each sensor. The inverter 7 is arranged on one axial side (+Y side) relative to the motor 2. According to this embodiment, compared with the case where the inverter 7 is arranged on the radially outer side of the motor 2, the drive device 1 can be miniaturized in the radial direction.

[0050] The inverter 7 has a bus bar 7b. The bus bar 7b is a plate-shaped component made of a metal material with low resistance. The material of the bus bar 7b is, for example, copper. The bus bar 7b has a lead wire connection portion 7a at the end on the other axial side (-Y side). The lead wire 31k extending from the coil 31 is connected to the lead wire connection portion 7a. The inverter 7 of this embodiment has three bus bars 7b corresponding to the U phase, V phase and W phase. The inverter 7 passes an alternating current to the coil 31 of the stator 30 via the bus bar 7b. Figure 2As shown, an opening 61 for exposing the internal space to the radially outer side is provided in the housing 6. A worker and an assembling device (hereinafter, worker, etc.) insert a tool through the opening 61 to perform a connection operation of the lead wire connecting portion 7a.

[0051] <Power transmission unit>

[0052] like Figure 1 As shown, the power transmission unit 4 is arranged on the other axial side (-Y side) relative to the rotor 20. The power transmission unit 4 is connected to the rotor 20 and transmits the power of the rotor 20 to the output shaft 47. The power transmission unit 4 has a reduction gear 4a and a differential device 4b. The torque output from the motor 2 is transmitted to the differential device 4b via the reduction gear 4a. The reduction gear 4a is a parallel axis gear type reducer in which the rotation axis of each gear is arranged in parallel. When the vehicle turns, the differential device 4b absorbs the speed difference between the left and right wheels while transmitting the torque to the left and right wheels.

[0053] The reduction gear 4a includes a second shaft 44, a third shaft 45, a first gear 41, a second gear 42, and a third gear 43. The differential device 4b includes a ring gear 46g, a differential case 46, and a differential mechanism portion 46c disposed inside the differential case 46.

[0054] The second shaft 44 extends axially with the central axis J1 as the center. The second shaft 44 is arranged coaxially with the first shaft 21. The second shaft 44 is connected to the end of the other axial side (-Y side) of the first shaft 21 at the end of the one axial side (+Y side). The second shaft 44 rotates around the central axis J1 together with the first shaft 21.

[0055] The first gear 41 is provided on the outer peripheral surface of the second shaft 44. The first gear 41 rotates around the central axis J1 together with the second shaft 44. The third shaft 45 rotates around the intermediate axis J2 parallel to the central axis J1. The second gear 42 and the third gear 43 are arranged in parallel in the axial direction. The second gear 42 and the third gear 43 are provided on the outer peripheral surface of the third shaft 45. The second gear 42 and the third gear 43 are connected via the third shaft 45. The second gear 42 and the third gear 43 rotate around the intermediate axis J2. The second gear 42 meshes with the first gear 41. The third gear 43 meshes with the ring gear 46g of the differential device 4b.

[0056] The ring gear 46g rotates around the output axis J3 parallel to the central axis J1. The torque output from the motor 2 is transmitted to the ring gear 46g via the reduction gear 4a. The ring gear 46g is fixed to the differential case 46.

[0057] The differential case 46 includes a case portion 46b that accommodates a differential mechanism portion 46c therein and a differential case shaft 46a that protrudes axially to one side and the other side relative to the case portion 46b. The differential case shaft 46a is in a cylindrical shape extending axially with the output axis J3 as the center. The ring gear 46g is provided on the outer peripheral surface of the differential case shaft 46a. The differential case shaft 46a rotates together with the ring gear 46g with the output axis J3 as the center.

[0058] A pair of output shafts 47 are connected to the differential device 4b. The pair of output shafts 47 protrude from the differential case 46 of the differential device 4b to one side and the other side in the axial direction. The output shafts 47 are arranged on the inner side of the differential case shaft 46a. The output shafts 47 are rotatably supported on the inner peripheral surface of the differential case shaft 46a via bearings.

[0059] The torque output from the motor 2 is transmitted to the ring gear 46g of the differential device 4b via the second shaft 44, the first gear 41, the second gear 42, the third shaft 45, and the third gear 43 of the motor 2, and is output to the output shaft 47 via the differential mechanism portion 46c of the differential device 4b. The plurality of gears 41, 42, 43, and 46g of the power transmission unit 4 transmit the power of the motor 2 in the order of the second shaft 44, the third shaft 45, and the differential case shaft 46a.

[0060] <Casing>

[0061] The housing 6 has an inverter holder 6A, a housing body 6B, a gear cover 6C, and a water jacket 50. The inverter holder 6A, the housing body 6B, the gear cover 6C, and the water jacket 50 are different components. The inverter holder 6A is arranged on one axial side (+Y side) of the housing body 6B. The gear cover 6C is arranged on the other axial side (-Y side) of the housing body 6B. The water jacket 50 is arranged inside the housing body 6B.

[0062] The housing 6 is provided with a flow path 90 for the fluid L to flow. The fluid L is, for example, water or antifreeze. In addition, the fluid L may not be water. For example, the fluid L may be oil or other fluids. The flow path 90 includes an external pipe 97 passing through the outside of the housing 6 and a first flow path portion 91, a second flow path portion 92, a third flow path portion (flow path portion) 93, and a fourth flow path portion 94 passing through the inside of the housing 6.

[0063] The fluid L flows in the first flow path 91, the second flow path 92, the third flow path 93, and the fourth flow path 94 in the order of the first flow path 91, the second flow path 92, the third flow path 93, and the fourth flow path 94 in the housing 6. The fluid L mainly cools the inverter in the first flow path 91 and mainly cools the motor 2 in the third flow path 93.

[0064] The external pipe 97 is connected to the inverter holder 6A at the first connection portion 97a, and is connected to the housing body 6B at the second connection portion 97b. A radiator (not shown) for cooling the fluid L is arranged in the path of the external pipe 97. The external pipe 97 delivers the low-temperature fluid L into the housing 6 at the first connection portion 97a, and recovers the fluid L that has absorbed heat in the housing 6 and has a higher temperature at the second connection portion 97b.

[0065] The housing body 6B accommodates the motor 2 and is open on one axial side (+Y side). The housing body 6B has: an outer cylinder 65, which is cylindrical with the center axis J1 as the center; a partition wall 66, which is arranged on the other axial side (-Y side) of the outer cylinder 65 and covers the opening on the other axial side of the outer cylinder 65; and a concave portion 67, which is open on the other axial side (-Y side). That is, the housing 6 has a cylindrical outer cylinder 65 with the center axis J1 as the center.

[0066] The outer cylinder portion 65 surrounds the motor 2 from the radially outer side. The second flow path portion 92 and the fourth flow path portion 94 are provided in the outer cylinder portion 65. The second flow path portion 92 and the fourth flow path portion 94 are hole portions provided in the outer cylinder portion 65. The second flow path portion 92 extends in the axial direction inside the wall of the outer cylinder portion 65. The second flow path portion 92 connects the downstream side end portion of the first flow path portion 91 and the inlet portion 93a of the third flow path portion 93. The fourth flow path portion 94 extends in the radial direction. The fourth flow path portion 94 extends radially outward from the outlet portion 93b of the third flow path portion 93 and opens radially outward of the outer cylinder portion 65. The second connecting portion 97b of the external piping 97 is connected to the opening of the fourth flow path portion 94.

[0067] The partition wall portion 66 is provided with a shaft insertion hole 66h. A pair of bearings 5B and 5C and a sealing member 5S are arranged in the shaft insertion hole 66h. The bearing 5B supports the first shaft 21, and the bearing 5C supports the second shaft 44. The first shaft 21 and the second shaft 44 are connected to each other inside the shaft insertion hole 66h. The sealing member 5S is arranged between the two bearings 5B and 5C in the axial direction. The sealing member 5S seals between the inner peripheral surface of the shaft insertion hole 66h and the outer peripheral surface of the second shaft 44.

[0068] The gear cover 6C is fixed to the concave portion 67 of the housing body 6B. The gear cover 6C and the concave portion 67 constitute a storage space for storing the power transmission unit 4. The storage space of the power transmission unit 4 stores oil O. The oil O improves the lubricity of the power transmission unit 4.

[0069] The inverter holder 6A accommodates and supports the inverter 7. The inverter holder 6A covers the opening on one axial side (+Y side) of the case body 6B. The inverter holder 6A is provided with a first flow path 91 for cooling the inverter 7.

[0070] The water jacket 50 includes a cylindrical inner tube portion 51 centered on the central axis J1 and ribs 59 provided on the outer peripheral surface of the inner tube portion 51. That is, the housing 6 includes the inner tube portion 51. The inner tube portion 51 surrounds the stator 30 from the radially outer side and holds the stator 30. That is, the housing 6 surrounds the stator 30 from the radially outer side and holds the stator 30.

[0071] The inner cylinder 51 is arranged on the inner side of the outer cylinder 65. That is, the inner cylinder 51 is surrounded by the outer cylinder 65 from the radial outside. The outer diameter of the inner cylinder 51 is smaller than the inner diameter of the outer cylinder 65. Sealing portions 64c and 64d are arranged at both ends of the outer peripheral surface of the inner cylinder 51 in the axial direction. The sealing portions 64c and 64d of the present embodiment are O-rings arranged in grooves provided on the outer peripheral surface of the inner cylinder 51. The sealing portions 64c and 64d seal between the outer peripheral surface of the inner cylinder 51 and the outer cylinder 65. A gap that functions as the third flow path portion 93 is provided between the inner cylinder 51 and the outer cylinder 65 and between a pair of sealing portions 64c and 64d.

[0072] Here, one of the pair of sealing portions 64c, 64d located on one axial side (+Y side) is referred to as the first sealing portion 64d, and the other located on the other axial side (-Y side) is referred to as the second sealing portion 64c. In the present embodiment, the first sealing portion 64d is arranged between the inner tube portion 51 and the outer tube portion 65 and on one axial side (+Y side) of the third flow path portion 93, and the second sealing portion 64c is arranged on the other axial side (-Y side).

[0073] The rib 59 extends in a spiral shape with the central axis J1 as the center. The rib 59 has a front end portion located at the radially outer end. The front end portion of the rib 59 contacts the inner circumferential surface of the outer tube portion 65, or faces the inner circumferential surface of the outer tube portion 65 with a small gap therebetween. Thus, the rib 59 separates the outer circumferential surface of the inner tube portion 51 from the outer tube portion 65 to form a spiral third flow path portion 93.

[0074] The third flow path portion 93 is provided between the outer tube portion 65 and the inner tube portion 51. More specifically, the third flow path portion 93 is provided on the radially inner side of the outer tube portion 65 and on the radially outer side of the water jacket 50. The third flow path portion 93 extends in a spiral shape with the central axis J1 as the center. The third flow path portion 93 surrounds the stator 30 from the radially outer side. The fluid L flowing in the third flow path portion 93 cools the water jacket 50. The water jacket 50 contacts the stator core 32 and cools the stator core 32.

[0075] In the present embodiment, the case where the third flow path portion 93 extends in a spiral shape is described. However, the third flow path portion 93 only needs to surround the stator 30 and is not limited to the present embodiment. The third flow path portion 93 may also be a flow path that meanders in the axial direction or the circumferential direction. The flow path structure of the third flow path portion 93 can be determined according to the shape of the rib 59.

[0076] The inner circumferential surface of the inner tube portion 51 includes a fitting inner circumferential surface 50e, a first inner circumferential surface 50f, and a second inner circumferential surface 50g. The fitting inner circumferential surface 50e contacts the outer circumferential surface of the stator core. The stator core 32 is held on the fitting inner circumferential surface 50e. The inner diameters of the first inner circumferential surface 50f and the second inner circumferential surface 50g are larger than the inner diameter of the fitting inner circumferential surface 50e. The first inner circumferential surface 50f is located on one axial side (+Y side) of the fitting inner circumferential surface 50e. The second inner circumferential surface 50g is located on the other axial side (-Y side) of the fitting inner circumferential surface 50e.

[0077] The first inner peripheral surface 50f surrounds the first coil end 31a from the radially outer side via a gap. The second inner peripheral surface 50g surrounds the second coil end 31b from the radially outer side via a gap.

[0078] A plurality of first fins (fins) 55a and a plurality of second fins (fins) 55b are provided on the first inner peripheral surface 50f. Similarly, a plurality of third fins 55c are provided on the second inner peripheral surface 50g. A plurality of fins (first fins 55a and second fins 55b) arranged radially outward of the first coil end 31a and a plurality of third fins 55c arranged radially outward of the second coil end 31b are provided on the inner peripheral surface of the inner tube 51. The first fins 55a and the second fins 55b are respectively provided in the prescribed areas described later along the circumferential direction of the first inner peripheral surface 50f. The plurality of first fins 55a, the plurality of second fins 55b and the plurality of third fins 55c extend in the axial direction and are arranged in the circumferential direction, respectively.

[0079] The water jacket 50 is cooled by the fluid L flowing in the third flow path portion 93. According to the present embodiment, by providing the fins 55a, 55b, 55c on the inner peripheral surface of the water jacket 50, the surface area of ​​the water jacket 50 can be increased, and the cooling efficiency of the air in the space surrounded by the water jacket 50 can be improved.

[0080] According to the present embodiment, the first fin 55a, the second fin 55b, and the third fin 55c extend in the axial direction, respectively. Therefore, the first fin 55a, the second fin 55b, and the third fin 55c smoothly guide the air blown out from the fans 10A and 10B to the radially outer side and contacting the first inner peripheral surface 50f or the second inner peripheral surface 50g in the axial direction. Thus, the air inside the housing 6 can be circulated smoothly, and the cooling efficiency of the stator 30 and the rotor 20 can be improved.

[0081] <Bearing cage>

[0082] like Figure 2 As shown, the bearing holder 70 is located on one axial side (+Y side) of the stator 30. The bearing holder 70 covers the motor 2 from one axial side (+Y side). The bearing holder 70 is fixed to the end surface of the water jacket 50 on one axial side (+Y side).

[0083] The bearing holder 70 holds the first bearing (bearing) 5A. The first bearing 5A is disposed at an end portion on one axial side (+Y side) of the first shaft 21, and rotatably supports the rotor 20.

[0084] The bearing holder 70 is made of, for example, an aluminum alloy and is molded by die casting, etc. In addition, among the surfaces of the bearing holder 70 , surfaces serving as references during assembly are additionally cut using an end mill, etc.

[0085] Figure 3 It is a front view of the bearing holder 70 attached to the driving device 1 . Figure 4 It is a perspective view of the bearing retainer 70 .

[0086] The bearing holder 70 includes a main body portion 71 , a bearing holding portion 72 , a resolver holding portion 74 , a protruding portion 73 , and an outer edge portion 76 .

[0087] like Figure 4 As shown in FIG. 1 , the main body 71 is in the shape of a disk centered on the central axis J1. The bearing holding portion 72 is disposed at the center of the main body 71. That is, the main body 71 extends radially outward from the bearing holding portion 72.

[0088] A plurality of radial ribs 75 are provided on the surface of the main body 71 facing the other axial side (-Y side). The plurality of radial ribs 75 are arranged at equal intervals along the circumferential direction. Each radial rib 75 extends radially relative to the central axis J1. The radial inner end of the radial rib 75 is connected to the outer peripheral surface of the bearing retaining portion 72. The radial ribs 75 reinforce the main body 71 and the bearing retaining portion 72.

[0089] The main body 71 is provided with a central hole 71h, a first through hole 71a, and a second through hole 71b that penetrate in the axial direction. The central hole 71h is circular centered on the central axis J1. The end of the first shaft 21 on one axial side (+Y side) is inserted into the central hole 71h.

[0090] like Figure 3As shown, the first through hole 71a and the second through hole 71b are arranged along the circumferential direction centered on the central axis J1. The first through hole 71a and the second through hole 71b are respectively in the shape of long holes extending along the circumferential direction. The radial inner edge of the first through hole 71a and the radial inner edge of the second through hole 71b are roughly consistent in radial position. On the other hand, the radial outer edge of the first through hole 71a is arranged in a manner farther away from the central axis J1 than the radial inner edge of the second through hole 71b. In addition, the circumferential length of the first through hole 71a is sufficiently greater than the circumferential length of the second through hole 71b. Therefore, the opening area of ​​the first through hole 71a is sufficiently greater than the opening area of ​​the second through hole 71b.

[0091] The first through hole 71a allows the lead wire 31k extending from the coil 31 of the stator 30 to pass through. On the other hand, the second through hole 71b allows the temperature sensor wiring 81a extending from the temperature sensor 81 to pass through. The lead wire 31k and the temperature sensor wiring 81a passing through the first through hole 71a and the second through hole 71b are connected to the inverter 7 on one axial side (+Y side) of the bearing holder 70.

[0092] like Figure 2 As shown, the bearing holding portion 72 is cylindrical centered on the central axis J1. The bearing holding portion 72 protrudes from the surface of the main body 71 facing the other axial side (-Y side) toward the other axial side (-Y side). The bearing holding portion 72 surrounds the first bearing 5A from the radially outer side to hold the first bearing 5A. In addition, the bearing holding portion 72 surrounds the central hole 71h from the radially outer side.

[0093] The rotary transformer holding portion 74 is cylindrical centered on the central axis J1. The rotary transformer holding portion 74 protrudes from the surface of the main body 71 facing the axial one side (+Y side) toward the axial one side (+Y side). The rotary transformer holding portion 74 and the bearing holding portion 72 are respectively arranged on the axial one side (+Y side) and the axial other side (-Y side) across the main body 71. The rotary transformer holding portion 74 surrounds the rotary transformer stator 29b from the radial outside to hold the rotary transformer stator 29b.

[0094] like Figure 4 As shown, the outer edge portion 76 is provided along the outer edge of the main body portion 71. The outer edge portion 76 extends in a substantially annular shape along the circumferential direction with the central axis J1 as the center. A plurality of first fastening portions 76b are provided on the outer edge portion 76. The first fastening portions 76b are arranged at substantially equal intervals along the circumferential direction.

[0095] The first fastening portion 76b is provided with a hole portion 76a. Figure 2As shown, the first fixing screw 3 is inserted into the hole 76a and screwed into the surface of the inner tube 51 facing the axial one side (+Y side), thereby fixing the bearing holder 70 to the inner tube 51. That is, the first fastening portion 76b is fixed to the inner tube 51.

[0096] like Figure 4 As shown in FIG. 1 , five first fastening portions 76b are provided on the outer edge portion 76 of the present embodiment. The width dimension of the outer edge portion 76 along the radial direction increases at the first fastening portion 76b. That is, the outer edge portion 76 protrudes radially inward and outward at the first fastening portion 76b. According to the present embodiment, by setting the first fastening portion 76b wider than other parts of the outer edge portion 76, it is possible to fully ensure the first fastening portion 76b to be fastened to the first fixing screw 3 (see FIG. 1 ). Figure 2 )'s head and the area of ​​the fastening surface with the inner tube portion 51.

[0097] like Figure 4 As shown, the protrusion 73 protrudes from the surface of the main body 71 facing the other axial side (-Y side) toward the other axial side (-Y side). The bearing retainer 70 of this embodiment is provided with a protrusion 73. The protrusion 73 of this embodiment is a rib extending in an arc shape along the circumferential direction. The protrusion 73 is provided along the outer edge of the main body 71. In addition, the protrusion 73 is arranged on the radial inner side of the outer edge portion 76.

[0098] The protrusion 73 of this embodiment is provided in a region of 270° or more around the central axis J1. The protrusion 73 is interrupted at a portion where the first through hole 71a is provided. That is, the first through hole 71a is disposed between an end 73b on one circumferential side and an end 73c on the other circumferential side of the protrusion 73.

[0099] The protrusion 73 of this embodiment has a plurality of (five in this embodiment) detour portions 73d. Each detour portion 73d is located radially inward of the first fastening portion 76b. The protrusion 73 avoids the first fastening portion 76b at the detour portion 73d and detours radially inward. The protrusion 73 extends in a circumferentially curved manner at a constant curvature radius centered on the central axis J1 in the region other than the detour portion 73d.

[0100] The protrusion 73 has an outer side surface 73a facing radially outward. The outer side surface 73a is mainly a cylindrical surface centered on the central axis J1. In addition, the outer side surface 73a is concavely curved toward the radial inside at a portion where the detour portion 73d is provided.

[0101] like Figure 3As shown, when viewed from the axial direction, the protrusion 73 extends circumferentially along an imaginary circle VC centered on the central axis J1. In addition, the protrusion 73 is embedded in the inner peripheral surface of the inner tube portion 51. More specifically, the outer side surface 73a of the protrusion 73 and the first inner peripheral surface 50f of the inner tube portion 51 are radially opposed and embedded.

[0102] According to the present embodiment, the protrusion 73 provided on the bearing holder 70 is embedded in the inner side surface of the inner tube portion 51, so that the bearing holder 70 is positioned relative to the inner tube portion 51 in the radial direction. The stator 30 is fixed to the inner tube portion 51, so the rotor 20 is supported by the bearing holder 70 via the first bearing 5A. According to the present embodiment, the rotor 20 can be supported by the stator 30 with high precision, and the air gap between the stator 30 and the rotor 20 can be made uniform in the circumferential direction, thereby improving the driving efficiency of the motor 2.

[0103] The protrusion 73 of this embodiment is embedded in the inner circumferential surface of the inner tube portion 51. According to this embodiment, the radial thickness of the inner tube portion 51 can be reduced compared to the case where a recessed portion for fitting is provided on the end surface of one axial side (+Y side) of the inner tube portion 51. As a result, the drive device 1 can be miniaturized in the radial direction.

[0104] In the present embodiment, when viewed from the axial direction, the first through hole 71a is arranged on the imaginary circle VC. Thus, the protrusion 73 is formed into a shape interrupted at the portion where the first through hole 71a is provided. According to the present embodiment, compared with the case where the first through hole is arranged radially inside the imaginary circle VC avoiding the protrusion 73, the first through hole 71a can be arranged close to the radial outside. By arranging the first through hole 71a close to the radial outside, the lead wire 31k passing through the first through hole 71a can also be arranged radially outside, and in the connection operation of the lead wire 31k and the bus bar 7b, the operator and the like can easily approach the lead wire connection portion 7a from the radial outside. As a result, the assembly process of the drive device 1 can be simplified. In addition, according to the present embodiment, compared with the case where the protrusion is arranged at a position closer to the radial outside than the imaginary circle VC passing through the first through hole 71a avoiding the first through hole 71a, the bearing retainer 70 and the inner cylinder 51 can be miniaturized in the radial direction. According to the present embodiment, the drive device 1 can be reduced in size in the radial direction.

[0105] According to the present embodiment, the protrusion 73 and the first through hole 71a are arranged at different positions in the circumferential direction. The radial rigidity of the main body 71 is reduced at the portion where the first through hole 71a is provided. If the first through hole 71a is provided radially inside the protrusion 73, the bearing holder 70 may be deformed at the protrusion 73 due to the force received by the bearing holder 70 from the inner cylinder 51, thereby causing the support of the rotor 20 by the bearing holder 70 to become unstable. According to the present embodiment, even if a force is applied to the protrusion 73, the deformation of the bearing holder 70 can be suppressed.

[0106] According to the present embodiment, the bearing retainer 70 has a protrusion 73. In addition, the first through hole 71a of the present embodiment is located between the end 73b on one circumferential side of the protrusion 73 and the end 73c on the other circumferential side. According to the present embodiment, by making the protrusion 73 sufficiently long in the circumferential direction, the fitting length with the inner tube 51 can also be ensured to be large. As a result, it is easy to position the bearing retainer 70 relative to the inner tube 51, and the bearing retainer 70 is stably maintained. In addition, in the present embodiment, since the protrusion 73 extends within a range of more than 270° in the circumferential direction centered on the central axis J1, the stability of positioning can be further improved.

[0107] like Figure 4 As shown, the protrusion 73 of this embodiment can suppress the protrusion amount of the first fastening portion 76b to the radial outside by providing the detour portion 73d and fully ensure the fastening area of ​​the first fastening portion 76b. In addition, the detour portion 73d is embedded in the convex portion of the inner side surface of the inner tube portion 51, so that the bearing holder 70 can be suppressed from rotating relative to the inner tube portion 51. However, the protrusion 73 does not have to have the detour portion 73d. Figure 5 It is a partial stereoscopic view of the protrusion 273 of the modified example without the detour portion 73d. The protrusion 273 of this modified example extends in an arc shape along the circumferential direction in the same manner as the first embodiment. However, the protrusion 273 of this modified example also extends in an arc shape around the central axis J1 with a uniform radius of curvature on the radial inner side of the first fastening portion 276b. Therefore, the outer side surface 273b of the protrusion 273 becomes a uniform cylindrical surface centered on the central axis J1 within the entire length of the protrusion 273. According to this modified example, a uniform outer side surface 273b can be embedded in the inner circumferential surface of the inner cylinder portion 51, which can improve the positioning accuracy of the bearing retainer 70 relative to the inner cylinder portion 51.

[0108] like Figure 3As shown, the first inner circumferential surface 50f of the inner tube portion 51 can be divided into a first area A1 and a second area A2 in the circumferential direction. Here, the first area A1 is an area arranged radially outside the protrusion 73, and the second area A2 is an area arranged at a portion where the protrusion 73 is interrupted. The protrusion 73 is embedded in the first inner circumferential surface 50f of the inner tube portion 51 in the first area A1.

[0109] like Figure 2 As shown, among the plurality of fins provided on the first inner peripheral surface 50f, the first fin 55a is provided in the first region A1, and the second fin 55b is provided in the second region A2. Preferably, the end position P1 of the axial one side (+Y side) of the first fin 55a is closer to the axial other side (-Y side) than the end position P2 of the axial one side (+Y side) of the second fin 55b. That is, preferably, the end of the axial one side (+Y side) of the first fin 55a in the first region A1 is located closer to the axial other side (-Y side) than the end of the axial one side (+Y side) of the second fin 55b in the second region A2. Thus, it is possible to suppress the interference between the first fin 55a and the protrusion 73 when the protrusion 73 is embedded in the first region A1, and it is possible to provide the first fin 55a and the second fin 55b in the axial direction of the first inner peripheral surface 50f in the largest possible region.

[0110] like Figure 2 As shown, the protrusion 73 of the present embodiment is located at a position closer to the axial side (+Y side) than the first coil end 31a. Therefore, the insulation distance between the protrusion 73 and the first coil end 31a can be ensured. According to the present embodiment, the protrusion 73 is located at a position closer to the radial outside than the first coil end 31a. Therefore, it is easy to make the main body 71 of the bearing retainer 70 close to the coil 31 in the axial direction, and the axial dimension of the drive device 1 can be miniaturized.

[0111] In the present embodiment, the protrusion 73 is located at a position closer to the axial side (+Y side) than the first sealing portion 64d. According to the present embodiment, the first sealing portion 64d located at the axial side (+Y side) of the third flow path portion 93 does not overlap with the protrusion 73 in the radial direction. Therefore, according to the present embodiment, it is possible to suppress the radial enlargement of the inner cylinder portion 51. In addition, when viewed from the axial direction, the protrusion 73 of the present embodiment is arranged at a position different from the first sealing portion 64d. And, when viewed from the axial direction, the protrusion 73 overlaps with the third flow path portion 93.

[0112] In the bearing holder 70 of the present embodiment, both the protrusion 73 and the bearing holder 72 protrude from the surface of the main body 71 facing the other axial side (-Y side) toward the other axial side (-Y side). The outer side surface 73a of the protrusion 73 and the inner peripheral surface of the bearing holder 72 function as fitting surfaces, respectively, so it is preferred to implement cutting processing. According to the present embodiment, the protrusion 73 and the bearing holder 72 are both provided on the surface of the other axial side (-Y side) of the main body 71, so it is possible to perform cutting processing from the same direction (the other axial side). Thus, the workability of the cutting processing is improved. In addition, according to the present embodiment, both the protrusion 73 and the bearing holder 72 can be processed without removing the bearing holder 70 from the machine tool, so the coaxiality between the outer side surface 73a of the protrusion 73 and the inner peripheral surface of the bearing holder 72 can be improved. Thus, the position accuracy of the rotor 20 relative to the stator 30 can be improved.

[0113] According to the present embodiment, the resolver stator 29b is fixed to the bearing holder 70. In addition, the axial position of the resolver stator 29b overlaps with the axial position of the protrusion 73. According to the present embodiment, by arranging the protrusion 73 and the resolver stator 29b to overlap in the axial direction, the bearing holder 70 can be miniaturized in the axial direction, and the axial dimension of the drive device 1 can be miniaturized.

[0114] like Figure 3 As shown, the rotary transformer wiring 29c of the rotary transformer stator 29b is fixed to the bearing holder 70 in the path. More specifically, the rotary transformer wiring 29c is fixed to the surface of the main body 71 facing the axial side (+Y side) by the fixing tool 8. The fixing tool 8 is threadedly fastened to the main body 71, and a threaded hole for threading the fixing tool 8 is provided on the surface of the main body 71 facing the axial side. In the present embodiment, when viewed from the axial direction, the threaded fastening portion of the fixing tool overlaps with the protrusion 73. Therefore, when the threaded hole for threading the fixing tool 8 is provided in the main body 71, the threaded hole can be provided sufficiently deep, and the matching amount of the thread can be fully ensured.

[0115] <Second embodiment>

[0116] Figure 6 It is a front view of the bearing holder 170 attached to the driving device 101 of the second embodiment. Figure 7 It is a perspective view of a bearing holder 170 according to the second embodiment.

[0117] The following is based on Figure 6 and Figure 7A bearing holder 170 of a second embodiment of the present invention will be described. The structure of the bearing holder 170 of the drive device 101 of the present embodiment is different from that of the above embodiment. The same reference numerals are used for the same components as those of the above embodiment, and their description is omitted.

[0118] like Figure 7 As shown, the bearing holder 170 includes a main body portion 71, a bearing holding portion 72, and a rotary transformer holding portion 74 (see Figure 6 ), a plurality of protrusions 173 and an outer edge portion 76. The main body portion 71 is provided with a first through hole 71a and a second through hole 71b. In addition, the outer edge portion 76 is provided with a plurality of first fastening portions 76b arranged along the circumferential direction. That is, the bearing holder 170 has a plurality of first fastening portions 76b.

[0119] As in the above-mentioned embodiment, the protrusion 173 protrudes from the surface of the main body 71 facing the other axial side (-Y side) toward the other axial side (-Y side). In the bearing retainer 170 of this embodiment, three protrusions 173 are provided. Each protrusion 173 is a rib extending in a substantially arc shape along the circumferential direction. The protrusion 173 is provided along the outer edge of the main body 71. In addition, the protrusion 173 is arranged on the radial inner side of the outer edge portion 76.

[0120] like Figure 6 As shown, a plurality of protrusions 173 are arranged on an imaginary circle VC. The three protrusions 173 of the present embodiment are substantially the same shape and are arranged rotationally symmetrically around the central axis J1. In the following description, when the three protrusions 173 are distinguished from each other, they are referred to as the first protrusion 173A, the second protrusion 173B, and the third protrusion 173C. When the bearing retainer 170 is observed from one axial side (+Y side), the first protrusion 173A, the second protrusion 173B, and the third protrusion 173C are arranged in sequence clockwise.

[0121] In the present embodiment, the first through hole 71a is arranged between the first protrusion 173A and the third protrusion 173C in the circumferential direction. That is, when viewed from the axial direction, the first through hole 71a is arranged on the imaginary circle VC. In addition, the first through hole 71a is located between a pair of protrusions 173 adjacent to each other in the circumferential direction among the plurality of protrusions 173.

[0122] According to the present embodiment, compared with the case where the first through hole is arranged radially inside the imaginary circle VC while avoiding the protrusion 173, the first through hole 71a can be arranged close to the radial outside, and the lead wire 31k can also be arranged radially outside. As a result, in the connection operation between the lead wire 31k and the bus bar 7b, it is easy for the operator to approach the lead wire connection portion 7a from the radial outside. In addition, according to the present embodiment, compared with the case where the protrusion is arranged radially outside the imaginary circle VC passing through the first through hole 71a while avoiding the first through hole 71a, the bearing retainer 170 and the inner cylinder portion 51 can be miniaturized in the radial direction.

[0123] The bearing holder 170 of the present embodiment is provided with a plurality of protrusions 173 arranged in the circumferential direction. According to the bearing holder 170 of the present embodiment, it is possible to achieve weight reduction compared with the bearing holder 170 having the protrusions 173 connected in an integrated manner as in the above-mentioned embodiment. In addition, in the present embodiment, the case where the bearing holder 70 has three protrusions 173 is described, but the number of the protrusions 173 is not limited to the present embodiment, and may be two, or may be four or more.

[0124] Preferably, the protrusion 173 and the first fastening portion 76b are arranged at different positions in the circumferential direction. The first fastening portion 76b is easy to be enlarged in the radial direction in order to ensure the fastening area. By staggering the circumferential positions of the protrusion 173 and the first fastening portion 76b, the drive device 101 can be suppressed from being enlarged in the radial direction as a whole. In the bearing holder 170, the outer side surface 173a of the protrusion 173 and the fastening surface of the first fastening portion 76b are both contact surfaces with the inner tube portion 51. According to the present embodiment, by staggering the circumferential positions of the protrusion 173 and the first fastening portion 76b, the contact surface between the bearing holder 170 and the inner tube portion 51 can be dispersedly arranged in the circumferential direction. According to the present embodiment, when a force is applied between the bearing holder 170 and the inner tube portion 51, it is possible to suppress the bearing holder 170 and the inner tube portion 51 from being locally applied with a large force, causing them to be greatly deformed.

[0125] The inner tube portion 51 of the present embodiment has a plurality of (four in the present embodiment) second fastening portions 56 fixed to the outer tube portion 65 at the end portion on one axial side (+Y side). The plurality of second fastening portions 56 are arranged at equal intervals in the circumferential direction. A hole portion for inserting the second fixing screw 13 is provided in each of the plurality of second fastening portions 56. The second fastening portion 56 is fastened to the outer tube portion 65 by screwing the second fixing screw 13 into a threaded hole provided on the surface of the outer tube portion 65 facing the one axial side (+Y side).

[0126] In the present embodiment, it is preferred that the protrusion 173 and the second fastening portion 56 are arranged at different positions in the circumferential direction. In the present embodiment, the first protrusion 173A and the second protrusion 173B are arranged at different positions in the circumferential direction from the second fastening portion 56. However, a part of the third protrusion 173C overlaps with the circumferential position of the second fastening portion 56. The most preferred mode is a mode in which all the protrusions 173 and the second fastening portion 56 are arranged staggered in the circumferential direction.

[0127] By arranging the protrusion 173 and the second fastening portion 56 at different positions in the circumferential direction, when a force is applied from the bearing holder 170 to the outer tube portion 65 via the inner tube portion 51, the portions that may become the force transmission path can be dispersedly arranged in the circumferential direction. According to this embodiment, when a force is applied from the bearing holder 170 to the inner tube portion 51, it is possible to suppress a large force from being locally applied to the inner tube portion 51 and causing the inner tube portion 51 to be greatly deformed.

[0128] In the present embodiment, the protrusion 173 and the second through hole 71b are arranged at different positions in the circumferential direction. The radial rigidity of the main body 71 is reduced at the portion where the second through hole 71b is provided. If the second through hole 71b is provided radially inside the protrusion 173, it is possible that the bearing retainer 170 is deformed at the protrusion 173 due to the force received by the bearing retainer 170 from the inner cylinder 51, thereby causing the support of the rotor 20 by the bearing retainer 170 to become unstable. According to the present embodiment, even if a force is applied to the protrusion 173, the deformation of the bearing retainer 170 can be suppressed.

[0129] like Figure 6 As shown, in the present embodiment, the outer tube portion 65 is provided with a second flow path portion 92 extending in the axial direction. The protrusion 173 and the second flow path portion 92 are arranged at different positions in the circumferential direction. When a radial force is applied to the bearing holder 170, it is possible that a load is applied to the second flow path portion 92 of the outer tube portion 65 from the outer side surface 173a of the protrusion 173 via the inner tube portion 51. According to the present embodiment, the protrusion 173 and the second flow path portion 92 are arranged at different positions in the circumferential direction, so even if a radial force is applied to the bearing holder 170, it is possible to suppress a large load from being applied to the second flow path portion 92.

[0130] The various embodiments and modifications of the present invention have been described above, but each structure and combination thereof in each embodiment and modification is only an example, and addition, omission, substitution and other changes of the structure can be made within the scope of the gist of the present invention. In addition, the present invention is not limited by the embodiments.

[0131] For example, in the above embodiment, the coil is a bendable wire mounted on the stator, and the lead wire extending from the coil has a structure obtained by bundling a plurality of wires using a crimping terminal. However, the coil may also be a segmented coil composed of a highly rigid flat wire, and the lead wire extending from the coil is also a single flat wire.

[0132] In addition, the present technology can adopt the following structures.

[0133] (1) A drive device, comprising: a rotor, which is rotatable around a central axis; a stator, which surrounds the rotor from the radially outer side; a housing, which surrounds the stator from the radially outer side and holds the stator; a bearing, which supports the rotor so that it can rotate; and a bearing holder, which is located on one axial side of the stator and holds the bearing, the housing having a cylindrical inner tube portion and an outer tube portion centered on the central axis, a flow path portion being provided between the inner tube portion and the outer tube portion, and the bearing holder having: a main body portion, It is in the shape of a circular plate with the central axis as the center; a bearing retaining portion that retains the bearing; a first fastening portion that is fixed to the inner cylinder portion; and a protrusion that protrudes from the surface of the main body portion toward the other axial side, and when viewed from the axial direction, the protrusion extends circumferentially along an imaginary circle with the central axis as the center, and the protrusion is embedded in the inner circumferential surface of the inner cylinder portion. A first through hole is provided in the main body portion for the lead wire extending from the coil of the stator to pass through, and when viewed from the axial direction, the first through hole is arranged on the imaginary circle.

[0134] (2) The drive device according to (1), wherein the bearing holder has one protrusion, and the first through hole is located between an end portion on one side in the circumferential direction and an end portion on the other side in the circumferential direction of the protrusion.

[0135] (3) The drive device according to (1), wherein the bearing holder has a plurality of the protrusions arranged on the imaginary circle, and the first through hole is located between a pair of the protrusions that are adjacent to each other in the circumferential direction among the plurality of the protrusions.

[0136] (4) The drive device according to (3), wherein the bearing holder has a plurality of the first fastening portions arranged in a circumferential direction, and the protruding portion and the first fastening portions are arranged at different positions in the circumferential direction.

[0137] (5) A drive device according to (3) or (4), wherein the inner tube portion has a plurality of second fastening portions fixed to the outer tube portion at an end portion on one axial side, and the protrusion and the second fastening portions are arranged at different positions in the circumferential direction.

[0138] (6) A drive device according to any one of (3) to (5), wherein the drive device has a temperature sensor installed on the stator, and a second through hole is provided in the main body for passing a temperature sensor wiring extending from the temperature sensor, and the protrusion and the second through hole are arranged at different positions in the circumferential direction.

[0139] (7) A drive device according to any one of (1) to (6), wherein the stator has a first coil end located at one end portion in the axial direction and a second coil end located at the other end portion in the axial direction, and the protrusion is located closer to one side in the axial direction than the first coil end.

[0140] (8) A drive device according to any one of (1) to (7), wherein the stator has a first coil end located at one end of the axial direction and a second coil end located at the other end of the axial direction, and the protrusion is located radially outward of the first coil end.

[0141] (9) A drive device according to any one of (1) to (8), wherein the stator has a first coil end located at one end portion in the axial direction and a second coil end located at the other end portion in the axial direction, and a plurality of fins are provided on the inner circumferential surface of the inner cylinder portion and arranged radially outward of the first coil end portion, the plurality of fins extend in the axial direction and are arranged in the circumferential direction, the inner circumferential surface of the inner cylinder portion is divided into a first region and a second region in the circumferential direction, the protrusion is embedded in the inner circumferential surface of the inner cylinder portion in the first region, and the end portion on one axial side of the fin in the first region is located closer to the other axial side than the end portion on one axial side of the fin in the second region.

[0142] (10) A drive device according to any one of (1) to (9), wherein a sealing portion is arranged between the inner cylinder portion and the outer cylinder portion and on one axial side of the flow path portion, and the protrusion is located on the axial side of the sealing portion.

[0143] (11) The drive device according to any one of (1) to (10), wherein the bearing holding portion is cylindrical and protrudes toward the other axial side from a surface of the main body portion that faces the other axial side.

[0144] (12) A drive device according to any one of (1) to (11), wherein the drive device has a rotation sensor for detecting the rotation of the rotor, the rotation sensor is fixed to the bearing retainer, and the axial position of the rotation sensor overlaps the axial position of the protrusion.

[0145] (13) A drive device according to any one of (1) to (12), wherein the drive device has a power transmission part that is connected to the rotor and transmits the power of the rotor to the output shaft, and the power transmission part is arranged on the other axial side relative to the rotor.

[0146] Description of symbols

[0147] 1, 101: drive device; 2: motor; 4: power transmission part; 5A, 5B, 5C: bearing; 6: housing; 20: rotor; 29b: rotary transformer stator (rotation sensor); 30: stator; 31: coil; 31a: first coil end; 31b: second coil end; 31k: lead wire; 47: output shaft; 51: inner cylinder; 55a: fin; 55a: first fin (fin); 55b: second fin (fin); 56: second fastening part; 64c: sealing part; 64d : The first sealing portion (sealing portion); 65: the outer cylinder portion; 70, 170: the bearing retainer; 71: the main body; 71a: the first through hole; 71b: the second through hole; 72: the bearing retaining portion; 73, 173, 273: the protrusion; 73b, 73c: the end portion; 76b, 276b: the first fastening portion; 81: the temperature sensor; 81a: the temperature sensor wiring; 93: the third flow path portion (flow path portion); A1: the first area; A2: the second area; J1: the center axis; VC: the imaginary circle.

Claims

1. A driving device, comprising: A rotor capable of rotating about a central axis; a stator surrounding the rotor from the radial outside; A housing, which surrounds the stator from the radial outside and holds the stator; a bearing that rotatably supports the rotor; and A bearing retainer is located on one axial side of the stator to retain the bearing. The housing has a cylindrical inner tube portion and an outer tube portion centered on the central axis. A flow path is provided between the inner tube portion and the outer tube portion. The bearing retainer has: A main body, which is in the shape of a circular plate centered on the central axis; A bearing holding portion, which holds the bearing; a first fastening portion fixed to the inner cylindrical portion; as well as a protrusion protruding from a surface of the main body portion facing the other axial side to the other axial side, When viewed from the axial direction, the protrusion extends circumferentially along an imaginary circle centered on the central axis, and the protrusion is embedded in the inner circumferential surface of the inner cylindrical portion. The main body is provided with a first through hole through which a lead wire extending from the coil of the stator passes. When viewed in the axial direction, the first through hole is arranged on the imaginary circle.

2. The driving device according to claim 1, wherein: The bearing retainer has one protrusion. The first through hole is located between an end portion on one side in the circumferential direction and an end portion on the other side in the circumferential direction of the protruding portion.

3. The driving device according to claim 1, wherein: The bearing retainer has a plurality of protrusions arranged on the imaginary circle, The first through hole is located between a pair of the protrusions that are adjacent to each other in the circumferential direction among the plurality of protrusions.

4. The driving device according to claim 3, wherein: The bearing holder has a plurality of first fastening portions arranged along the circumferential direction, The protruding portion and the first fastening portion are arranged at different positions in the circumferential direction.

5. The driving device according to claim 3, wherein: The inner tube portion has a plurality of second fastening portions fixed to the outer tube portion at an end portion on one axial side. The protruding portion and the second fastening portion are arranged at different positions from each other in the circumferential direction.

6. The driving device according to claim 3, wherein: The drive device has a temperature sensor installed on the stator. The main body is provided with a second through hole through which a temperature sensor wiring extending from the temperature sensor passes. The protrusion and the second through hole are arranged at different positions in the circumferential direction.

7. The driving device according to claim 1, wherein: The stator has a first coil end located at one end portion in the axial direction and a second coil end portion located at the other end portion in the axial direction. The protruding portion is located on one side in the axial direction relative to the first coil end portion.

8. The driving device according to claim 1, wherein: The stator has a first coil end located at one end portion in the axial direction and a second coil end portion located at the other end portion in the axial direction. The protrusion is located radially outward of the first coil end.

9. The driving device according to claim 1, wherein: The stator has a first coil end located at one end portion in the axial direction and a second coil end portion located at the other end portion in the axial direction. A plurality of fins are provided on the inner peripheral surface of the inner cylindrical portion and are arranged radially outward of the first coil end. The plurality of fins extend in the axial direction and are arranged in the circumferential direction. The inner circumferential surface of the inner tube portion is divided into a first area and a second area in the circumferential direction. The protrusion is embedded in the inner peripheral surface of the inner tube portion in the first region, An end portion on one axial direction side of the fin in the first region is located closer to the other axial direction side than an end portion on one axial direction side of the fin in the second region.

10. The driving device according to claim 1, wherein: A sealing portion is arranged between the inner tube portion and the outer tube portion and on one axial side of the flow path portion. The protrusion is located on one side in the axial direction relative to the sealing portion.

11. The driving device according to claim 1, wherein: The bearing holding portion has a cylindrical shape and protrudes toward the other axial side from a surface of the main body portion that faces the other axial side.

12. The driving device according to claim 1, wherein: The drive device has a rotation sensor for detecting the rotation of the rotor. The rotation sensor is fixed to the bearing holder, The axial position of the rotation sensor overlaps with the axial position of the protrusion.

13. The driving device according to claim 1, wherein: The drive device includes a power transmission unit connected to the rotor to transmit the power of the rotor to the output shaft. The power transmission portion is arranged on the other axial side with respect to the rotor.

Images