WO2024070228A1 - Drive device - Google Patents

Abstract

One aspect of a drive device according to the present invention comprises a rotor, a stator, a housing, a bearing, and a bearing holder that is located on one side in the axial direction of the stator and that holds the bearing. The housing includes a cylindrical inner tube section centered on the central axis, and an outer tube section. A flow path section is provided between the inner tube section and the outer tube section. The bearing holder includes: a disc-shaped body section centered on the central axis; a bearing holding part that holds the bearing; a first fastening part fixed to the inner tube section; and a protruding part that protrudes toward the other side in the axial direction from the surface of the body section facing the other side in the axial direction. The protruding part extends in the circumferential direction running along an imaginary circle centered on the central axis when viewed from the axial direction, and fits to the inner circumferential surface of the inner tube section. A first through hole, through which a lead wire extending from a stator coil is passed, is provided in the body section. The first through hole is disposed on an imaginary circle when viewed from the axial direction.

Description

Drive unit

The present invention relates to a drive device.
This application claims priority based on Japanese Patent Application No. 2022-157698, filed in Japan on September 30, 2022, the contents of which are incorporated herein by reference.

With the growing interest in electric vehicles in recent years, various methods for cooling motors have been developed. One known example of a motor cooling method is a structure in which the outer circumference of the stator is surrounded by a water jacket to uniformly cool the stator. In such a structure, a bearing holder that supports the bearings is generally fixed to the water jacket. For example, the bracket (bearing holder) is positioned relative to the frame by inserting a protrusion on the bracket into a recess on the end face of a cylindrical frame (water jacket) in which a refrigerant passage is provided (for example, Patent Document 1).

JP 2012-228105 A

　In conventional structures, it is necessary to ensure that the water jacket is thick enough to provide a recess on the end face of the water jacket, which can lead to an increase in the size of the drive unit.

In view of the above, one of the objectives of the present invention is to provide a drive unit that can be made smaller.

One embodiment of the drive device of the present invention includes a rotor rotatable around a central axis, a stator surrounding the rotor from the radial outside, a housing surrounding the stator from the radial outside and holding the stator, a bearing supporting the rotor rotatably, and a bearing holder located on one axial side of the stator and holding the bearing. The housing has a cylindrical inner cylindrical portion centered on the central axis, and an outer cylindrical portion. A flow path portion is provided between the inner cylindrical portion and the outer cylindrical portion. The bearing holder has a disk-shaped main body portion centered on the central axis, a bearing holding portion that holds the bearing, a first fastening portion fixed to the inner cylindrical portion, and a protruding portion that protrudes to the other axial side from a surface of the main body portion facing the other axial side. The protruding portion extends circumferentially along a virtual circle centered on the central axis when viewed from the axial direction, and fits into the inner peripheral surface of the inner cylindrical 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 positioned on the imaginary circle when viewed in the axial direction.

One aspect of the present invention provides a drive device that can be made compact.

FIG. 1 is a conceptual diagram of a drive device according to a first embodiment. FIG. 2 is a partial cross-sectional view of the drive device of the first embodiment. FIG. 3 is a front view of a bearing holder attached to the drive device of the first embodiment. FIG. 4 is a perspective view of the bearing holder of the first embodiment. FIG. 5 is a partial perspective view of a modified protrusion. FIG. 6 is a front view of a bearing holder attached to the drive unit of the second embodiment. FIG. 7 is a perspective view of a bearing holder according to the second embodiment.

In the following explanation, each part will be explained by defining the direction of gravity based on the positional relationship when the drive unit 1 is mounted on a vehicle positioned on a horizontal road surface. In addition, in the drawings, the XYZ coordinate system is shown as a three-dimensional Cartesian coordinate system as appropriate.

In the XYZ coordinate system, the Z-axis direction indicates the vertical direction (i.e., up-down direction), the +Z direction is the upper side (opposite the direction of gravity), and the -Z direction is the lower side (direction of gravity). The X-axis direction is perpendicular to the Z-axis direction and indicates the front-to-rear direction of the vehicle on which the drive unit 1 is mounted. The Y-axis direction is perpendicular to both the X-axis and Z-axis directions and indicates the width direction (left-right direction) of the vehicle.

Unless otherwise specified in the following description, the direction parallel to the central axis J1 of the motor 2 (Y-axis direction) will be referred to simply as the "axial direction", the radial direction centered on the central axis J1 will be referred to simply as the "radial direction", and the circumferential direction centered on the central axis J1, i.e., around the axis of the central axis J1, will be referred to simply as the "circumferential direction". However, the above "parallel direction" also includes directions that are approximately parallel. Furthermore, in the following description, of the axial directions of the central axis J1, the +Y direction may be referred to simply as one axial side, and the -Y direction may be referred to simply as the other axial side.

First Embodiment
<Drive unit>
Fig. 1 is a conceptual diagram of a drive device 1 according to a first embodiment. Fig. 2 is a partial cross-sectional view of the drive device 1 according to the first embodiment.
The drive device 1 of this embodiment is mounted on a vehicle that uses 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.

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

<Motor>
The motor 2 in this embodiment is an inner rotor type three-phase AC motor. The motor 2 functions both as an electric motor and as a generator. The configuration of the motor 2 is not limited to this embodiment, and may be, for example, an AC motor with four or more phases.

The motor 2 includes a rotor 20 that can rotate around a central axis J1 that extends horizontally, and a stator 30 that faces the rotor 20 across a gap. That is, the drive unit 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 disposed inside the stator 30.

The rotor 20 has a first shaft 21, a rotor core 24 fixed to the outer circumferential 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.

As shown in FIG. 2, the rotor core 24 is provided with a shaft insertion hole 24h and multiple ventilation holes 24a, 24b. The shaft insertion hole 24h and the ventilation holes 24a, 24b penetrate the rotor core 24 in the axial direction. The shaft insertion hole 24h and the ventilation holes 24a, 24b open at both axial end faces of the rotor core 24. The shaft insertion hole 24h extends in the axial direction around the central axis. The first shaft 21 is inserted into the shaft insertion hole 24h.

The multiple air holes 24a, 24b are arranged in the circumferential direction. The air holes 24a, 24b include first air holes 24a and second air holes 24b. The first air holes 24a and the second air holes 24b are arranged alternately in the circumferential direction. The rotor 20 of this embodiment is provided with four first air holes 24a and four second air holes 24b. The cross-sectional shapes of the first air holes 24a and the second air holes 24b are the same. The first air holes 24a and the second air holes 24b have different flow directions of air flowing inside.

The first shaft 21 extends in the axial direction around the central axis J1. The first shaft 21 is rotatably supported by bearings 5A and 5B. In the following description, of the pair of bearings 5A and 5B supporting the first shaft 21, one located on one axial side (+Y side) may be referred to as the first bearing 5A, and the other located on the other axial side (-Y side) may be referred to as the second bearing 5B.

The resolver rotor 29a is fixed to the end of the first shaft 21 on one axial side (+Y side). In this embodiment, the resolver rotor 29a is located on one axial side (+Y side) of the bearing 5A.

The pair of fans 10A, 10B are fixed to the end faces of the rotor core 24 on one axial side and the other axial side, respectively. The pair of fans 10A, 10B rotate together with the rotor 20. The pair of fans 10A, 10B are attached to the rotor 20 in different positions and orientations.

As the rotor 20 rotates, the pair of fans 10A, 10B blow air through the air holes 24a, 24b and outward in the radial direction. The air blown out from the fans 10A, 10B hits the coil ends 31a, 31b located radially outward of the fans 10A, 10B. The fans 10A, 10B cool the rotor 20 and the coil ends 31a, 31b.

As shown in FIG. 1, the stator 30 is held in the housing 6. The stator 30 surrounds the rotor 20 from the radial outside. The stator 30 has an annular stator core 32 centered on the central axis J1, a coil 31 attached to the stator core 32, lead wires 31k drawn from the coil 31, and an insulator (not shown) interposed between the stator core 32 and the coil 31.

The stator core 32 has an annular core back portion 32a and a number of teeth 32b extending radially inward from the core back portion 32a. The teeth 32b are arranged in the circumferential direction. A coil wire is arranged between the teeth 32b arranged in the circumferential direction. The coil wire located between adjacent teeth 32b constitutes the coil 31. In other words, the coil 31 is arranged in the stator core 32. The insulator is made of an insulating material.

The coil 31 has a pair of coil ends 31a, 31b that protrude in the axial direction from both axial end faces of the stator core 32. The coil ends 31a, 31b are formed by bundling together parts of the coil wire that connects the slots of the stator core 32. In the following description, when distinguishing between the pair of coil ends 31a, 31b, the one on one axial side (+Y side) is called the first coil end 31a, and the other on the other axial side (-Y side) is called the second coil end 31b. In other words, 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.

The lead wire 31k extends from the coil 31 to one axial side (+Y side). In this embodiment, the stator 30 has three lead wires 31k corresponding to the U-phase, V-phase, and W-phase. The lead wire 31k has a twisted conductor, a crimp terminal crimped to its tip, and an insulating tube (not shown) that covers the outer periphery of the coil wire. The lead wire 31k is connected to the lead wire connection portion 7a of the bus bar 7b at the crimp terminal at the tip.

<Resolver>
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 together with the rotor 20 around the central axis J1.

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

<Temperature sensor>
The temperature sensor 81 is attached to the coil 31 of the stator 30 to measure 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.

<Inverter>
The inverter 7 shown in Fig. 1 is electrically connected to the motor 2. The inverter 7 is connected to a battery (not shown) mounted on the vehicle, and converts direct current supplied from the battery into alternating current and supplies it to the motor 2. The inverter 7 also controls the motor 2 based on commands from an external device and detection results of each sensor. The inverter 7 is disposed on one axial side (+Y side) of the motor 2. According to this embodiment, the drive device 1 can be made smaller in the radial direction than when the inverter 7 is disposed radially outside the motor 2.

The inverter 7 has a bus bar 7b. The bus bar 7b is a plate-shaped member made of a metal material with low electrical resistance. The material of the bus bar 7b is, for example, copper. The bus bar 7b has a lead wire connection part 7a at the end on the other axial side (-Y side). The lead wire connection part 7a is connected to the lead wire 31k extending from the coil 31. 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 AC current through the bus bar 7b to the coil 31 of the stator 30. As shown in FIG. 2, the housing 6 has an opening 61 that exposes the internal space radially outward. A worker or an assembly device (hereinafter, a worker, etc.) inserts a tool through the opening 61 to connect the lead wire connection part 7a.

<Power transmission section>
As shown in FIG. 1, the power transmission unit 4 is disposed on the other axial side (-Y side) of the rotor 20. The power transmission unit 4 is connected to the rotor 20 and transmits the power of the rotor 20 to an output shaft 47. The power transmission unit 4 has a reduction gear 4a and a differential gear 4b. Torque output from the motor 2 is transmitted to the differential gear 4b via the reduction gear 4a. The reduction gear 4a is a parallel shaft gear type reducer in which the rotation axes of the gears are arranged in parallel. When the vehicle turns, the differential gear 4b transmits the same torque to both the left and right wheels while absorbing the speed difference between the left and right wheels.

The reduction gear 4a has a second shaft 44, a third shaft 45, a first gear 41, a second gear 42, and a third gear 43. The differential gear 4b has a ring gear 46g, a differential case 46, and a differential mechanism part 46c arranged inside the differential case 46.

The second shaft 44 extends in the axial direction around the central axis J1. The second shaft 44 is arranged coaxially with the first shaft 21. The second shaft 44 is connected at its end on one axial side (+Y side) to the end on the other axial side (-Y side) of the first shaft 21. The second shaft 44 rotates around the central axis J1 together with the first shaft 21.

The first gear 41 is provided on the outer peripheral surface of the second shaft 44. The first gear 41 rotates together with the second shaft 44 around the central axis J1. 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 side by side 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.

The ring gear 46g rotates about an output axis J3 that is 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.

The differential case 46 has a case portion 46b that houses the differential mechanism portion 46c therein, and a differential case shaft 46a that protrudes from the case portion 46b on one axial side and the other axial side. The differential case shaft 46a is cylindrical and extends axially with the output axis J3 as its 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 its center.

The 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 on one axial side and the other axial side. The output shafts 47 are disposed inside the differential case shafts 46a. The output shafts 47 are rotatably supported on the inner peripheral surface of the differential case shafts 46a via bearings.

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 part 46c of the differential device 4b. The multiple gears 41, 42, 43, and 46g of the power transmission part 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.

<Housing>
The housing 6 has an inverter holder 6A, a housing main body 6B, a gear cover 6C, and a water jacket 50. The inverter holder 6A, the housing main body 6B, the gear cover 6C, and the water jacket 50 are each separate members. The inverter holder 6A is disposed on one axial side (+Y side) of the housing main body 6B. The gear cover 6C is disposed on the other axial side (-Y side) of the housing main body 6B. The water jacket 50 is disposed inside the housing main body 6B.

The housing 6 is provided with a flow path 90 through which the fluid L flows. The fluid L is, for example, water or antifreeze. Note that the fluid L does not have to be water. For example, the fluid L may be oil or another fluid. The flow path 90 includes an external pipe 97 that passes through the outside of the housing 6, and a first flow path section 91, a second flow path section 92, a third flow path section (flow path section) 93, and a fourth flow path section 94 that pass through the inside of the housing 6.

The fluid L flows through the first flow path section 91, the second flow path section 92, the third flow path section 93, and the fourth flow path section 94 in that order inside the housing 6. The fluid L mainly cools the inverter in the first flow path section 91, and mainly cools the motor 2 in the third flow path section 93.

The external pipe 97 is connected to the inverter holder 6A at the first connection part 97a, and to the housing main body 6B at the second connection part 97b. A radiator (not shown) for cooling the fluid L is arranged in the path of the external pipe 97. The external pipe 97 sends low-temperature fluid L into the housing 6 at the first connection part 97a, and recovers the fluid L whose temperature has increased by absorbing heat within the housing 6 at the second connection part 97b.

The housing body 6B houses the motor 2 and opens on one axial side (+Y side). The housing body 6B has a cylindrical outer tube portion 65 centered on the central axis J1, a partition portion 66 that is disposed on the other axial side (-Y side) of the outer tube portion 65 and covers the opening on the other axial side of the outer tube portion 65, and a recessed portion 67 that opens on the other axial side (-Y side). In other words, the housing 6 has a cylindrical outer tube portion 65 centered on the central axis J1.

The outer tubular portion 65 surrounds the motor 2 from the radial outside. The outer tubular portion 65 is provided with a second flow passage portion 92 and a fourth flow passage portion 94. The second flow passage portion 92 and the fourth flow passage portion 94 are holes provided in the outer tubular portion 65. The second flow passage portion 92 extends along the axial direction inside the wall of the outer tubular portion 65. The second flow passage portion 92 connects the downstream end of the first flow passage portion 91 and the inlet portion 93a of the third flow passage portion 93. The fourth flow passage portion 94 extends along the radial direction. The fourth flow passage portion 94 extends radially outward from the outlet portion 93b of the third flow passage portion 93 and opens radially outward of the outer tubular portion 65. The opening of the fourth flow passage portion 94 is connected to the second connecting portion 97b of the external piping 97.

A shaft insertion hole 66h is provided in the partition portion 66. A pair of bearings 5B, 5C and a seal member 5S are disposed 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 seal member 5S is disposed between the two bearings 5B, 5C in the axial direction. The seal member 5S seals between the inner circumferential surface of the shaft insertion hole 66h and the outer circumferential surface of the second shaft 44.

The gear cover 6C is fixed to the recessed portion 67 of the housing body 6B. The gear cover 6C and the recessed portion 67 form an accommodation space that accommodates the power transmission unit 4. Oil O is stored in the accommodation space for the power transmission unit 4. The oil O increases the lubricity of the power transmission unit 4.

The inverter holder 6A houses and supports the inverter 7. The inverter holder 6A covers the opening on one axial side (+Y side) of the housing body 6B. The inverter holder 6A is provided with a first flow passage portion 91 that cools the inverter 7.

The water jacket 50 has a cylindrical inner cylindrical portion 51 centered on the central axis J1, and ribs 59 provided on the outer peripheral surface of the inner cylindrical portion 51. That is, the housing 6 has the inner cylindrical portion 51. The inner cylindrical portion 51 surrounds the stator 30 from the radial outside and holds the stator 30. That is, the housing 6 surrounds the stator 30 from the radial outside and holds the stator 30.

The inner cylindrical portion 51 is disposed inside the outer cylindrical portion 65. That is, the inner cylindrical portion 51 is surrounded by the outer cylindrical portion 65 from the radial outside. The outer diameter of the inner cylindrical portion 51 is smaller than the inner diameter of the outer cylindrical portion 65. Seal portions 64c, 64d are disposed at both axial ends of the outer peripheral surface of the inner cylindrical portion 51. In this embodiment, the seal portions 64c, 64d are O-rings disposed in grooves provided on the outer peripheral surface of the inner cylindrical portion 51. The seal portions 64c, 64d seal between the outer peripheral surface of the inner cylindrical portion 51 and the outer cylindrical portion 65. Between the inner cylindrical portion 51 and the outer cylindrical portion 65, a gap that functions as a third flow path portion 93 is provided between the pair of seal portions 64c, 64d.

Here, of the pair of seal portions 64c, 64d, the one located on one axial side (+Y side) is referred to as the first seal portion 64d, and the other located on the other axial side (-Y side) is referred to as the second seal portion 64c. In this embodiment, the first seal portion 64d is disposed on one axial side (+Y side) of the third flow path portion 93 between the inner tubular portion 51 and the outer tubular portion 65, and the second seal portion 64c is disposed on the other axial side (-Y side).

The rib 59 extends spirally around the central axis J1. The rib 59 has a tip located at the radially outer end. The tip of the rib 59 contacts the inner circumferential surface of the outer tubular portion 65 or faces it with a small gap between them. As a result, the rib 59 separates the outer circumferential surface of the inner tubular portion 51 and the outer tubular portion 65, forming a spiral third flow path portion 93.

The third flow path portion 93 is provided between the outer cylindrical portion 65 and the inner cylindrical portion 51. More specifically, the third flow path portion 93 is provided radially inside the outer cylindrical portion 65 and radially outside the water jacket 50. The third flow path portion 93 extends spirally around the central axis J1. The third flow path portion 93 surrounds the stator 30 from the radial outside. The fluid L flowing through the third flow path portion 93 cools the water jacket 50. The water jacket 50 comes into contact with the stator core 32 and cools the stator core 32.

In this embodiment, the third flow path portion 93 extends in a spiral shape. However, the third flow path portion 93 is not limited to this embodiment as long as it surrounds the stator 30. The third flow path portion 93 may be a flow path that meanders in the axial or circumferential direction. The flow path configuration of the third flow path portion 93 can be determined by the shape of the rib 59.

The inner circumferential surface of the inner cylindrical portion 51 includes a mating inner circumferential surface 50e, a first inner circumferential surface 50f, and a second inner circumferential surface 50g. The mating inner circumferential surface 50e contacts the outer circumferential surface of the stator core. The stator core 32 is held by the mating 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 mating inner circumferential surface 50e. The first inner circumferential surface 50f is located on one axial side (+Y side) of the mating inner circumferential surface 50e. The second inner circumferential surface 50g is located on the other axial side (-Y side) of the mating inner circumferential surface 50e.

The first inner circumferential surface 50f surrounds the first coil end 31a from the radial outside via a gap. The second inner circumferential surface 50g surrounds the second coil end 31b from the radial outside via a gap.

The first inner peripheral surface 50f is provided with a plurality of first fins (fins) 55a and a plurality of second fins (fins) 55b. Similarly, the second inner peripheral surface 50g is provided with a plurality of third fins 55c. The inner peripheral surface of the inner cylindrical portion 51 is provided with a plurality of fins (first fins 55a and second fins 55b) arranged radially outward from the first coil end 31a, and a plurality of third fins 55c arranged radially outward from the second coil end 31b. The first fins 55a and the second fins 55b are each provided in a predetermined region along the circumferential direction of the first inner peripheral surface 50f, which will be described later. The first fins 55a, the second fins 55b, and the third fins 55c each extend along the axial direction and are arranged along the circumferential direction.

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

According to this embodiment, the first fin 55a, the second fin 55b, and the third fin 55c each extend along the axial direction. Therefore, the first fin 55a, the second fin 55b, and the third fin 55c smoothly guide the air that is blown outward in the radial direction from the fans 10A, 10B and hits the first inner circumferential surface 50f or the second inner circumferential surface 50g along the axial direction. This allows the air to circulate smoothly inside the housing 6, improving the cooling efficiency of the stator 30 and the rotor 20.

<Bearing holder>
2, 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 an end face of the water jacket 50 on one axial side (+Y side).

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

The bearing holder 70 is made of, for example, an aluminum alloy, and is formed by casting such as die casting. In addition, cutting is performed using an end mill or the like on the surfaces of the bearing holder 70 that serve as reference surfaces during assembly.

Fig. 3 is a front view of the bearing holder 70 attached to the drive device 1. Fig. 4 is a perspective view of the bearing holder 70.
The bearing holder 70 has a main body portion 71 , a bearing holding portion 72 , a resolver holding portion 74 , a protrusion 73 , and an outer edge portion 76 .

As shown in FIG. 4, the main body 71 is disk-shaped and centered on the central axis J1. The bearing holder 72 is disposed in the center of the main body 71. In other words, the main body 71 extends radially outward from the bearing holder 72.

A number of radial ribs 75 are provided on the surface of the main body 71 facing the other axial side (-Y side). The multiple radial ribs 75 are arranged at equal intervals along the circumferential direction. Each radial rib 75 extends radially from the central axis J1. The radially inner ends of the radial ribs 75 are connected to the outer peripheral surface of the bearing holder 72. The radial ribs 75 reinforce the main body 71 and the bearing holder 72.

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 and 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.

As shown in FIG. 3, the first through hole 71a and the second through hole 71b are arranged side by side in the circumferential direction centered on the central axis J1. The first through hole 71a and the second through hole 71b are each an elongated hole extending in the circumferential direction. The radially inner edge of the first through hole 71a and the radially inner edge of the second through hole 71b are approximately aligned in the radial direction. On the other hand, the radially outer edge of the first through hole 71a is arranged farther away from the central axis J1 than the radially inner edge of the second through hole 71b. In addition, the circumferential length of the first through hole 71a is sufficiently larger than the circumferential length of the second through hole 71b. Therefore, the opening area of the first through hole 71a is sufficiently larger than the opening area of the second through hole 71b.

The first through hole 71a passes the lead wire 31k extending from the coil 31 of the stator 30. Meanwhile, the second through hole 71b passes the temperature sensor wiring 81a extending from the temperature sensor 81. The lead wire 31k and 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.

As shown in FIG. 2, the bearing retaining portion 72 is cylindrical and centered on the central axis J1. The bearing retaining portion 72 protrudes toward the other axial side (-Y side) from the surface of the main body portion 71 facing that side. The bearing retaining portion 72 surrounds the first bearing 5A from the radial outside and retains the first bearing 5A. The bearing retaining portion 72 also surrounds the central hole 71h from the radial outside.

The resolver holding portion 74 is cylindrical and centered on the central axis J1. The resolver holding portion 74 protrudes to one axial side (+Y side) from a surface of the main body portion 71 facing that side. The resolver holding portion 74 and the bearing holding portion 72 are disposed on one axial side (+Y side) and the other axial side (-Y side) of the main body portion 71, respectively. The resolver holding portion 74 surrounds the resolver stator 29b from the radial outside and holds the resolver stator 29b.

As shown in FIG. 4, 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 centered on the central axis J1. 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.

The first fastening portions 76b each have a hole 76a. As shown in FIG. 2, the bearing holder 70 is fixed to the inner cylindrical portion 51 by inserting the first fixing screw 3 into the hole 76a and then screwing it to the surface of the inner cylindrical portion 51 facing one axial side (+Y side). In other words, the first fastening portions 76b are fixed to the inner cylindrical portion 51.

As shown in FIG. 4, five first fastening portions 76b are provided on the outer edge portion 76 of this embodiment. The outer edge portion 76 has a larger radial width at the first fastening portions 76b. That is, the outer edge portion 76 protrudes radially inward and outward at the first fastening portions 76b. According to this embodiment, the first fastening portions 76b are provided wider than other portions of the outer edge portion 76, thereby ensuring a sufficient contact area between the first fastening portions 76b and the head of the first fixing screw 3 (see FIG. 2) and a sufficient area of the fastening surface with the inner tubular portion 51.

As shown in FIG. 4, 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 holder 70 of this embodiment is provided with one protrusion 73. The protrusion 73 of this embodiment is a rib that extends in an arc shape along the circumferential direction. The protrusion 73 is provided along the outer edge of the main body 71. Furthermore, the protrusion 73 is positioned radially inward of the outer edge 76.

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

The protrusion 73 in this embodiment has multiple (five in this embodiment) detours 73d. Each detour 73d is located radially inward of the first fastening portion 76b. The protrusion 73 detours radially inward at the detours 73d to avoid the first fastening portion 76b. In the area other than the detours 73d, the protrusion 73 extends in a curved circumferential direction with a constant radius of curvature centered on the central axis J1.

The protrusion 73 has an outer surface 73a that faces radially outward. The outer surface 73a is a cylindrical surface that is mainly centered on the central axis J1. In addition, the outer surface 73a is curved concavely radially inward at the portion where the detour portion 73d is provided.

As shown in FIG. 3, the protrusion 73 extends circumferentially along an imaginary circle VC centered on the central axis J1 when viewed from the axial direction. The protrusion 73 also fits into the inner peripheral surface of the inner cylindrical portion 51. More specifically, the outer surface 73a of the protrusion 73 and the first inner peripheral surface 50f of the inner cylindrical portion 51 fit together in a radially opposed relationship.

In this embodiment, the protrusions 73 on the bearing holder 70 fit into the inner surface of the inner cylindrical portion 51, thereby positioning the bearing holder 70 radially relative to the inner cylindrical portion 51. The stator 30 is fixed to the inner cylindrical portion 51, and the rotor 20 is supported by the bearing holder 70 via the first bearing 5A. In this embodiment, the rotor 20 can be supported with high precision relative to the stator 30, 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.

The protrusion 73 in this embodiment fits into the inner peripheral surface of the inner tubular portion 51. According to this embodiment, the radial thickness of the inner tubular portion 51 can be made smaller than when a fitting recess is provided on the end face of the inner tubular portion 51 on one axial side (+Y side). As a result, the drive unit 1 can be made smaller in the radial direction.

In this embodiment, the first through hole 71a is disposed on the imaginary circle VC when viewed from the axial direction. As a result, the protruding portion 73 is interrupted at the portion where the first through hole 71a is provided. According to this embodiment, the first through hole 71a can be disposed radially outward, compared to the case where the first through hole is disposed radially inside the imaginary circle VC to avoid the protruding portion 73. By disposing the first through hole 71a radially outward, the lead wire 31k passing through the first through hole 71a can also be disposed radially outward, and in the connection work between the lead wire 31k and the bus bar 7b, it becomes easier for workers to access the lead wire connection portion 7a from the radial outside. As a result, the assembly process of the drive unit 1 can be simplified. According to this embodiment, the bearing holder 70 and the inner cylindrical portion 51 can be made smaller in the radial direction, compared to the case where the protruding portion is disposed radially outward from the imaginary circle VC passing through the first through hole 71a to avoid the first through hole 71a. According to this embodiment, the drive unit 1 can be made smaller in the radial direction.

According to this embodiment, the protrusion 73 and the first through hole 71a are disposed at different positions in the circumferential direction. The main body 71 has low radial rigidity in the portion where the first through hole 71a is provided. If the first through hole 71a is provided radially inward of the protrusion 73, the force received by the bearing holder 70 from the inner cylindrical portion 51 at the protrusion 73 may cause the bearing holder 70 to deform, causing the bearing holder 70 to become unstable in its support of the rotor 20. According to this embodiment, deformation of the bearing holder 70 can be suppressed even when force is applied to the protrusion 73.

According to this embodiment, the bearing holder 70 has one protrusion 73. The first through hole 71a in this 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 this embodiment, the protrusion 73 is made sufficiently long in the circumferential direction, so that a large fitting length with the inner cylindrical portion 51 can be ensured. As a result, it becomes easier to position the bearing holder 70 relative to the inner cylindrical portion 51, and the bearing holder 70 is held stably. Note that in this embodiment, the protrusion 73 extends over a range of 270° or more in the circumferential direction centered on the central axis J1, which further improves the stability of positioning.

4, the protrusion 73 of this embodiment is provided with a detour 73d, which suppresses the radially outward protrusion of the first fastening portion 76b while ensuring a sufficient fastening area of the first fastening portion 76b. In addition, the detour 73d fits into the convex portion on the inner surface of the inner cylindrical portion 51, thereby suppressing the rotation of the bearing holder 70 relative to the inner cylindrical portion 51. However, the protrusion 73 does not have to have the detour 73d. FIG. 5 is a partial perspective view of a protrusion 273 of a modified example that does not have a detour 73d. The protrusion 273 of this modified example extends in an arc shape along the circumferential direction as in the first embodiment. However, the protrusion 273 of this modified example extends in an arc shape around the central axis J1 with a uniform radius of curvature even on the radially inner side of the first fastening portion 276b. Therefore, the outer surface 273b of the protrusion 273 becomes a uniform cylindrical surface centered on the central axis J1 over the entire length of the protrusion 273. According to this modification, one uniform outer surface 273b can be fitted to the inner peripheral surface of the inner cylindrical portion 51, improving the positioning accuracy of the bearing holder 70 relative to the inner cylindrical portion 51.

As shown in FIG. 3, the first inner circumferential surface 50f of the inner tubular portion 51 can be divided into a first region A1 and a second region A2 in the circumferential direction. Here, the first region A1 is a region located radially outside the protrusion 73, and the second region A2 is a region located at the portion where the protrusion 73 ends. The protrusion 73 fits into the first inner circumferential surface 50f of the inner tubular portion 51 in the first region A1.

As shown in FIG. 2, among the multiple 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. It is preferable that the end position P1 on one axial side (+Y side) of the first fin 55a is located on the other axial side (-Y side) of the end position P2 on one axial side (+Y side) of the second fin 55b. In other words, it is preferable that the end on one axial side (+Y side) of the first fin 55a in the first region A1 is located on the other axial side (-Y side) of the end on one axial side (+Y side) of the second fin 55b in the second region A2. This makes it possible to provide the first fin 55a and the second fin 55b in as wide an area as possible in the axial direction of the first inner peripheral surface 50f while suppressing interference between the first fin 55a and the protrusion 73 with the protrusion 73 fitted in the first region A1.

As shown in FIG. 2, the protrusion 73 in this embodiment is located on one axial side (+Y side) of the first coil end 31a. This ensures an insulation distance between the protrusion 73 and the first coil end 31a. According to this embodiment, the protrusion 73 is located radially outward of the first coil end 31a. This makes it easier to bring the main body 71 of the bearing holder 70 closer to the coil 31 in the axial direction, and allows the axial dimension of the drive unit 1 to be reduced.

In this embodiment, the protrusion 73 is located on one axial side (+Y side) of the first seal portion 64d. According to this embodiment, the first seal portion 64d, which is located on one 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 this embodiment, the inner tube portion 51 can be prevented from becoming large in the radial direction. Furthermore, the protrusion 73 in this embodiment is located at a different position from the first seal portion 64d when viewed from the axial direction. Furthermore, the protrusion 73 overlaps with the third flow path portion 93 when viewed from the axial direction.

In the bearing holder 70 of this embodiment, the protruding portion 73 and the bearing holding portion 72 both protrude from the surface of the main body portion 71 facing the other axial side (-Y side) toward the other axial side (-Y side). The outer surface 73a of the protruding portion 73 and the inner peripheral surface of the bearing holding portion 72 are preferably cut to function as mating surfaces. According to this embodiment, since both the protruding portion 73 and the bearing holding portion 72 are provided on the surface of the other axial side (-Y side) of the main body portion 71, cutting can be performed from the same direction (other axial side). This improves the workability of the cutting process. In addition, according to this embodiment, since both the protruding portion 73 and the bearing holding portion 72 can be machined without removing the bearing holder 70 from the machine tool, the coaxiality of the outer surface 73a of the protruding portion 73 and the inner peripheral surface of the bearing holding portion 72 can be improved. This improves the positional accuracy of the rotor 20 relative to the stator 30.

According to this embodiment, the resolver stator 29b is fixed to the bearing holder 70. Furthermore, the axial position of the resolver stator 29b overlaps with the axial position of the protrusion 73. According to this embodiment, by arranging the protrusion 73 and the resolver stator 29b so as to overlap in the axial direction, the bearing holder 70 can be made smaller in the axial direction, and the axial dimension of the drive unit 1 can be made smaller.

As shown in FIG. 3, resolver wiring 29c of resolver stator 29b is fixed to bearing holder 70 in the path. More specifically, resolver wiring 29c is fixed by fixture 8 to a surface of main body 71 facing one axial side (+Y side). Fixture 8 is screwed to main body 71, and a screw hole for screwing fixture 8 is provided on the surface of main body 71 facing one axial side. In this embodiment, the screw portion of the fixture overlaps protrusion 73 when viewed from the axial direction. Therefore, when a screw hole for screwing fixture 8 is provided in main body 71, the screw hole can be provided sufficiently deep, and sufficient screw engagement can be ensured.

Second Embodiment
Fig. 6 is a front view of a bearing holder 170 attached to the driving device 101 of the second embodiment. Fig. 7 is a perspective view of the bearing holder 170 of the second embodiment.
A bearing holder 170 according to a second embodiment will be described below with reference to Fig. 6 and Fig. 7. The driving device 101 according to this embodiment differs from the above-described embodiment in the configuration of the bearing holder 170. Note that the same components as those in the above-described embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 7, the bearing holder 170 has a main body portion 71, a bearing holding portion 72, a resolver holding portion 74 (see FIG. 6), multiple 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. Furthermore, the outer edge portion 76 is provided with multiple first fastening portions 76b aligned in the circumferential direction. That is, the bearing holder 170 has multiple first fastening portions 76b.

Similar to the embodiment described above, the protrusions 173 protrude 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 holder 170 of this embodiment, three protrusions 173 are provided. Each protrusion 173 is a rib that extends in a substantially arc shape along the circumferential direction. The protrusions 173 are provided along the outer edge of the main body 71. Furthermore, the protrusions 173 are positioned radially inward of the outer edge 76.

As shown in FIG. 6, the multiple protrusions 173 are arranged on an imaginary circle VC. In this embodiment, the three protrusions 173 have substantially the same shape and are arranged rotationally symmetric about the central axis J1. In the following description, when the three protrusions 173 are to be distinguished from one another, they are referred to as the first protrusion 173A, the second protrusion 173B, and the third protrusion 173C. When the bearing holder 170 is viewed from one axial side (+Y side), the first protrusion 173A, the second protrusion 173B, and the third protrusion 173C are arranged in this order in a clockwise direction.

In this embodiment, the first through hole 71a is disposed between the first protrusion 173A and the third protrusion 173C in the circumferential direction. In other words, the first through hole 71a is disposed on the imaginary circle VC when viewed from the axial direction. The first through hole 71a is also located between a pair of protrusions 173 that are adjacent to each other in the circumferential direction among the multiple protrusions 173.

According to this embodiment, the first through hole 71a can be positioned radially outward, and the lead wire 31k can also be positioned radially outward, compared to when the first through hole is positioned radially inward of the virtual circle VC to avoid the protrusion 173. This makes it easier for workers to access the lead wire connection portion 7a from the radial outside when connecting the lead wire 31k to the bus bar 7b. Furthermore, according to this embodiment, the bearing holder 170 and the inner cylindrical portion 51 can be made smaller in the radial direction, compared to when the protrusion is positioned radially outward of the virtual circle VC that passes through the first through hole 71a to avoid the first through hole 71a.

The bearing holder 170 of this embodiment is provided with a plurality of protrusions 173 arranged in the circumferential direction. The bearing holder 170 of this embodiment can be made lighter than the bearing holder 170 having a continuous protrusion 173 as in the above-mentioned embodiment. Note that, although this embodiment has been described as having three protrusions 173, the number of protrusions 173 is not limited to this embodiment and may be two or four or more.

The protrusion 173 and the first fastening portion 76b are preferably disposed at different positions in the circumferential direction. The first fastening portion 76b tends to be large in the radial direction in order to secure a fastening area. By shifting the circumferential positions of the protrusion 173 and the first fastening portion 76b, the radial size of the entire drive device 101 can be suppressed. In the bearing holder 170, the outer surface 173a of the protrusion 173 and the fastening surface of the first fastening portion 76b are both contact surfaces with the inner cylindrical portion 51. According to this embodiment, by shifting the circumferential positions of the protrusion 173 and the first fastening portion 76b, the contact surfaces between the bearing holder 170 and the inner cylindrical portion 51 can be distributed in the circumferential direction. According to this embodiment, when a force is applied between the bearing holder 170 and the inner cylindrical portion 51, it is possible to suppress the bearing holder 170 and the inner cylindrical portion 51 from being significantly deformed due to a large force being applied locally.

The inner tubular portion 51 in this embodiment has a plurality of second fastening portions 56 (four in this embodiment) fixed to the outer tubular portion 65 at the end on one axial side (+Y side). The second fastening portions 56 are arranged at equal intervals in the circumferential direction. Each of the second fastening portions 56 is provided with a hole into which a second fixing screw 13 is inserted. The second fastening portions 56 are fastened to the outer tubular portion 65 by screwing the second fixing screws 13 into threaded holes provided on the surface of the outer tubular portion 65 facing one axial side (+Y side).

In this embodiment, it is preferable that the protrusions 173 and the second fastening portion 56 are positioned at different positions in the circumferential direction. In this embodiment, the first protrusions 173A and the second protrusions 173B are positioned at different positions in the circumferential direction from the second fastening portion 56. However, the third protrusions 173C partially overlap with the second fastening portion 56 in the circumferential direction. The most preferred embodiment is one in which all of the protrusions 173 are positioned circumferentially offset from the second fastening portion 56.

The protrusion 173 and the second fastening portion 56 are arranged at different positions in the circumferential direction, so that when a force is applied from the bearing holder 170 to the outer tubular portion 65 via the inner tubular portion 51, the portions that can become the force transmission path can be arranged in a distributed manner in the circumferential direction. According to this embodiment, when a force is applied from the bearing holder 170 to the inner tubular portion 51, it is possible to prevent the inner tubular portion 51 from being significantly deformed due to a large force being applied locally.

In this embodiment, the protrusion 173 and the second through hole 71b are disposed at different positions in the circumferential direction. The main body 71 has low radial rigidity in the portion where the second through hole 71b is provided. If the second through hole 71b is provided radially inside the protrusion 173, the force received by the bearing holder 170 from the inner cylindrical portion 51 at the protrusion 173 may cause the bearing holder 170 to deform, causing the bearing holder 170 to become unstable in its support of the rotor 20. According to this embodiment, deformation of the bearing holder 170 can be suppressed even when force is applied to the protrusion 173.

As shown in FIG. 6, the outer tubular portion 65 of this embodiment is provided with a second flow passage portion 92 extending in the axial direction. The protrusion 173 and the second flow passage portion 92 are arranged at different positions in the circumferential direction. When a radial force is applied to the bearing holder 170, there is a risk that a load will be applied from the outer surface 173a of the protrusion 173 to the second flow passage portion 92 of the outer tubular portion 65 via the inner tubular portion 51. According to this embodiment, since the protrusion 173 and the second flow passage portion 92 are arranged at different positions in the circumferential direction, it is possible to prevent a large load from being applied to the second flow passage portion 92 even when a radial force is applied to the bearing holder 170.

Various embodiments and variations of the present invention have been described above, but the configurations and combinations thereof in each embodiment and variation are merely examples, and additions, omissions, substitutions and other modifications of configurations are possible without departing from the spirit of the present invention. Furthermore, the present invention is not limited to the embodiments.

For example, in the above embodiment, the coil is a bendable conductor attached to the stator, and the lead wire extending from the coil has a structure in which multiple conductor wires are bundled together with a crimp terminal. However, the coil may be a segment coil made of a highly rigid rectangular wire, and the lead wire extending from the coil may also be a single rectangular wire.

The present technology can be configured as follows: (1) A rotor rotatable about a central axis, a stator surrounding the rotor from the radial outside, a housing surrounding the stator from the radial outside and holding the stator, a bearing rotatably supporting the rotor, and a bearing holder located on one axial side of the stator and holding the bearing, the housing having a cylindrical inner cylindrical portion centered on the central axis and an outer cylindrical portion, a flow path portion is provided between the inner cylindrical portion and the outer cylindrical portion, and the bearing holder is disposed on the central axis. A drive device having a disk-shaped main body part centered on a line, a bearing holding part that holds the bearing, a first fastening part fixed to the inner cylindrical part, and a protrusion that protrudes to the other axial direction side from a surface of the main body part facing the other axial direction side, the protrusion extending in the circumferential direction along a virtual circle centered on the central axis as viewed in the axial direction and fitting to an inner peripheral surface of the inner cylindrical part, the main body part being provided with a first through hole through which a lead wire extending from a coil of the stator passes, the first through hole being disposed on the virtual circle as viewed in the axial direction. (2) The drive device described in (1), in which the bearing holder has one of the protrusions, and the first through hole is located between an end portion on one circumferential side and an end portion on the other circumferential side of the protrusion. (3) The drive device described in (1), in which the bearing holder has a plurality of the protrusions arranged on the virtual circle, and the first through hole is located between a pair of the protrusions adjacent to each other in the circumferential direction among the plurality of the protrusions. (4) The driving device according to (3), wherein the bearing holder has a plurality of the first fastening portions arranged along the circumferential direction, and the protruding portion and the first fastening portion are disposed at different positions in the circumferential direction. (5) The driving device according to (3) or (4), wherein the inner cylindrical portion has a plurality of second fastening portions fixed to the outer cylindrical portion at an end portion on one axial side, and the protruding portion and the second fastening portion are disposed at different positions in the circumferential direction. (6) The driving device according to any one of (3) to (5), wherein the stator is provided with a temperature sensor attached thereto, and the main body portion is provided with a second through hole through which a temperature sensor wiring extending from the temperature sensor passes, and the protruding portion and the second through hole are disposed at different positions in the circumferential direction. (7) The driving device according to any one of (1) to (6), wherein the stator has a first coil end disposed at an end portion on one axial side and a second coil end disposed at an end portion on the other axial side, and the protruding portion is disposed on one axial side of the first coil end. (8) The drive device according to any one of (1) to (7), wherein the stator has a first coil end located at an end on one axial side and a second coil end located at an end on the other axial side, and the protruding portion is located radially outward of the first coil end. (9) The drive device according to any one of (1) to (8), wherein the stator has a first coil end located at an end on one axial side and a second coil end located at an end on the other axial side, and an inner circumferential surface of the inner cylindrical portion is provided with a plurality of fins arranged radially outward of the first coil end, extending along the axial direction, and aligned along the circumferential direction, the inner circumferential surface of the inner cylindrical portion being partitioned into a first region and a second region in the circumferential direction, the protruding portion fits into the inner circumferential surface of the inner cylindrical portion in the first region, and the end on one axial side of the fins in the first region is located on the other axial side of the end on one axial side of the fins in the second region. (10) The drive device according to any one of (1) to (9), in which a seal portion is disposed between the inner cylindrical portion and the outer cylindrical portion on one axial side of the flow passage portion, and the protruding portion is located on one axial side of the seal portion. (11) The drive device according to any one of (1) to (10), in which the bearing holder is cylindrical and protrudes on the other axial side from a surface of the main body portion facing the other axial side. (12) The drive device according to any one of (1) to (11), in which a rotation sensor that detects the rotation of the rotor is provided, the rotation sensor is fixed to the bearing holder, and the axial position of the rotation sensor overlaps with the axial position of the protruding portion. (13) The drive device according to any one of (1) to (12), in which a power transmission unit that is connected to the rotor and transmits the power of the rotor to an output shaft is provided, and the power transmission unit is located on the other axial side of the rotor.

1,101...Drive device, 2...Motor, 4...Power transmission section, 5A, 5B, 5C...Bearing, 6...Housing, 20...Rotor, 29b...Resolver stator (rotation sensor), 30...Stator, 31...Coil, 31a...First coil end, 31b...Second coil end, 31k...Outlet wire, 47...Output shaft, 51...Inner cylinder portion, 55a...Fin, 55a...First fin (fin), 55b...Second fin (fin), 56...Second fastening section, 64c ...sealing portion, 64d...first sealing portion (sealing portion), 65...outer cylinder portion, 70, 170...bearing holder, 71...main body portion, 71a...first through hole, 71b...second through hole, 72...bearing holding portion, 73, 173, 273...projection portion, 73b, 73c...end portion, 76b, 276b...first fastening portion, 81...temperature sensor, 81a...temperature sensor wiring, 93...third flow path portion (flow path portion), A1...first region, A2...second region, J1...center axis, VC...virtual circle

Claims (13)

1. A rotor rotatable about a central axis;
   a stator surrounding the rotor from the radially outer side;
   a housing that surrounds the stator from a radially outer side and holds the stator;
   a bearing that rotatably supports the rotor;
   a bearing holder located on one axial side of the stator and holding the bearing,
   The housing has an inner cylindrical portion and an outer cylindrical portion that are cylindrical and centered on the central axis line,
   A flow path is provided between the inner cylindrical portion and the outer cylindrical portion,
   The bearing holder includes:
   A disk-shaped main body having the central axis as a center;
   A bearing holder that holds the bearing;
   A first fastening portion fixed to the inner tubular portion;
   a protruding portion protruding from a surface of the main body portion facing the other axial direction to the other axial direction,
   the protrusion extends in a circumferential direction along a virtual circle centered on the central axis as viewed in the axial direction and fits into an inner peripheral surface of the inner cylindrical 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 the imaginary circle when viewed in the axial direction.
2. The bearing holder has one of the protrusions,
   The drive unit according to claim 1 , wherein the first through hole is located between an end portion on one circumferential side and an end portion on the other circumferential side of the protruding portion.
3. the bearing holder has a plurality of the protrusions arranged on the imaginary circle,
   The drive unit according to claim 1 , wherein the first through hole is located between a pair of the protruding portions that are adjacent to each other in a circumferential direction among the plurality of protruding portions.
4. the bearing holder has a plurality of the first fastening portions arranged along a circumferential direction,
   The drive unit according to claim 3 , wherein the protrusion and the first fastening portion are disposed at different positions in a circumferential direction.
5. the inner tubular portion has a plurality of second fastening portions fixed to the outer tubular portion at one end in the axial direction,
   The drive unit according to claim 3 , wherein the protruding portion and the second fastening portion are disposed at different positions from each other in a circumferential direction.
6. A temperature sensor is provided attached to the stator.
   The main body portion is provided with a second through hole through which a temperature sensor wire extending from the temperature sensor passes,
   The drive unit according to claim 3 , wherein the protrusion and the second through hole are disposed at different positions in a circumferential direction.
7. the stator has a first coil end located at one end in the axial direction and a second coil end located at the other end in the axial direction,
   The drive unit according to claim 1 , wherein the protruding portion is located on one axial side of the first coil end.
8. the stator has a first coil end located at one end in the axial direction and a second coil end located at the other end in the axial direction,
   The drive unit according to claim 1 , wherein the protruding portion is located radially outward of the first coil end.
9. the stator has a first coil end located at one end in the axial direction and a second coil end located at the other end in the axial direction,
   a plurality of fins are provided on an inner peripheral surface of the inner cylindrical portion, the fins being arranged radially outward of the first coil end, the fins extending along the axial direction, and the fins being arranged along the circumferential direction;
   The inner circumferential surface of the inner cylindrical portion is divided into a first region and a second region in a circumferential direction,
   the protrusion fits into an inner circumferential surface of the inner cylindrical portion in the first region,
   The drive unit according to claim 1 , wherein an end portion on one axial direction side of the fin in the first region is located on the other axial direction side of an end portion on one axial direction side of the fin in the second region.
10. a seal portion is disposed between the inner cylindrical portion and the outer cylindrical portion and on one axial side of the flow passage portion,
    The drive unit according to claim 1 , wherein the protruding portion is located on one axial side of the seal portion.
11. The drive device according to claim 1, wherein the bearing holder is cylindrical and protrudes in the other axial direction from a surface of the main body facing the other axial direction.
12. a rotation sensor that detects rotation of the rotor;
    The rotation sensor is fixed to the bearing holder,
    The drive device according to claim 1 , wherein an axial position of the rotation sensor overlaps with an axial position of the protrusion.
13. a power transmission section connected to the rotor and transmitting power of the rotor to an output shaft;
    The drive unit according to claim 1 , wherein the power transmission portion is disposed on the other axial side of the rotor.

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