Drive unit

Abstract

To provide a drive unit capable of smoothly supplying oil to a bearing while suppressing electrolytic corrosion of the bearing.SOLUTION: A drive unit includes a motor with a motor shaft, a bearing, a housing having a bearing holder 65, an insulating member 70 interposed between the bearing and the bearing holder 65, and an oil passage where oil flows. The bearing holder 65 has a holding cylinder 66 holding the bearing from the radially outer side, and a holding bottom 67 extending radially inward from one axial end of the holding cylinder 66. The insulating member 70 has an insulating cylinder 76 extending axially along the holding cylinder 66, and an insulating bottom 77 located at one axial end of the holding bottom 67 and radially extending along the holding bottom 67. The holding cylinder 66 is provided with a penetration 66a penetrating radially inside and outside. The oil passage has a first route arranged inside the penetration 66a and a second route 99 connecting the first route and the bearing.SELECTED DRAWING: Figure 4

Description

[Technical Field]

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

[0002] In recent years, the development of drive systems for vehicles has progressed with the spread of electric and hybrid vehicles. Such drive systems often store oil inside to improve bearing lubrication. However, in the motors of drive systems, a potential difference occurs between the rotor and stator due to high-frequency induction. This potential difference may cause electrolytic corrosion in the bearings that rotatably support the rotor. Patent Document 1 discloses a configuration that uses an insulating sleeve to hold the bearing as a countermeasure against electrolytic corrosion. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-255564 Summary of the Invention [Problem to be solved by the invention]

[0004] When the bearing is held from the radially outside by an insulating member, there is a problem in that it is difficult to secure a path for supplying oil from the radially outside of the bearing to increase the lubrication of the bearing.

[0005] In view of the above-mentioned problems, one aspect of the present invention aims to provide a drive device that enables smooth supply of oil to bearings while suppressing electrolytic corrosion of the bearings. [Means for solving the problem]

[0006] One aspect of the drive device of the present invention includes a motor having a motor shaft that rotates about a motor axis, a bearing that rotatably supports the motor shaft, a housing that accommodates the motor and holds the bearing in a bearing holder, an insulating member interposed between the bearing and the bearing holder, oil contained inside the housing, and an oil passage through which the oil flows. The bearing holder includes a cylindrical holder portion that holds the bearing from the radially outer side and a holding bottom portion that extends radially inward from one axial end of the cylindrical holder portion. The insulating member includes an insulating cylindrical portion that extends axially along the cylindrical holder portion and an insulating bottom portion located at one axial end of the holding bottom and extending radially along the holding bottom portion. The cylindrical holder portion is provided with a through-portion that penetrates radially from the inside to the outside. The oil passage includes a first passage disposed inside the through-portion and a second passage connecting the first passage and the bearing. [Effects of the Invention]

[0007] According to one aspect of the present invention, there is provided a drive device that enables smooth supply of oil to bearings while suppressing electrolytic corrosion of the bearings. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a conceptual diagram of a drive device according to one embodiment. [Figure 2] FIG. 2 is a plan view of the first wall portion of one embodiment. [Figure 3] FIG. 3 is a perspective view of an insulating member according to an embodiment. [Figure 4] FIG. 4 is a perspective view of an insulating member and a bearing holder according to one embodiment. [Figure 5] 5 is a cross-sectional view of the insulating member and the bearing holder taken along line VV in FIG. [Figure 6] FIG. 6 is a perspective view of an insulating member and a bearing holder according to one embodiment, seen from a different direction than FIG. [Figure 7]FIG. 7 is a perspective view of an insulating member and a bearing holding portion of the first modification. [Figure 8] FIG. 8 is a perspective view of an insulating member and a bearing holder according to the second modification. [Figure 9] FIG. 9 is a perspective view of an insulating member and a bearing holder according to the third modification. [Figure 10] FIG. 10 is a perspective view of an insulating member and a bearing holder according to the fourth modification. [Figure 11] FIG. 11 is a cross-sectional view of an insulating member and a bearing holder according to the fifth modification. [Figure 12] FIG. 12 is a perspective view of an insulating member and a bearing holder according to the sixth modification. [Figure 13] FIG. 13 is a perspective view of an insulating member and a bearing holder according to the seventh modification. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, a motor according to an embodiment of the present invention will be described with reference to the drawings. In the following explanation, the direction of gravity is defined based on the positional relationship when the drive unit 1 is mounted on a vehicle positioned on a horizontal road surface. The Y axis is also indicated appropriately in the drawings. The Y axis direction indicates the width direction (left-right direction) of the vehicle.

[0010] In the following description, unless otherwise specified, the direction parallel to the motor axis J2 of the motor 2 (the Y-axis direction) may be simply referred to as the "axial direction." Furthermore, the left side of the vehicle (i.e., the +Y side) may be simply referred to as one axial side, and the right side of the vehicle (i.e., the -Y side) may be simply referred to as the other axial side. Furthermore, the radial direction centered on the motor axis J2 may be simply referred to as the "radial direction," and the circumferential direction centered on the motor axis J2, i.e., around the axis of the motor axis J2, may be simply referred to as the "circumferential direction."

[0011] FIG. 1 is a conceptual diagram of a driving device 1 according to one embodiment. The drive unit 1 drives a vehicle. The drive unit 1 is mounted on a vehicle powered by a motor, 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 for the vehicle.

[0012] The drive device 1 includes a motor 2, a power transmission mechanism 3, a housing 6, oil O, a pump 96, a cooler 97, an oil passage 90 through which the oil O flows, a supply pipe (oil supply section) 95, a plurality of bearings 16, 16A, insulating members 70, 70A, and a static eliminator 9. Inside the housing 6, there is provided an accommodation space 80 partitioned into a motor chamber 81 that accommodates the motor 2 and a gear chamber 82 that accommodates the power transmission mechanism 3.

[0013] <Motor> The motor 2 is accommodated in a motor chamber 81 of the housing 6. The motor 2 includes a rotor 20 and a stator 30 located radially outside the rotor 20. The motor 2 is an inner rotor type motor that includes the stator 30 and the rotor 20 rotatably arranged inside the stator 30.

[0014] The rotor 20 rotates when power is supplied to the stator 30 from a battery (not shown). The rotor 20 has a motor shaft 21, a rotor core 24, and a rotor magnet (not shown). That is, the motor 2 has the motor shaft 21, the rotor core 24, and the rotor magnet. The rotor 20 rotates about the motor axis J2. The torque of the rotor 20 is transmitted to the power transmission mechanism 3.

[0015] The motor shaft 21 extends about the motor axis J2 and rotates about the motor axis J2. The motor shaft 21 is a hollow shaft that includes a hollow portion 22 having an inner circumferential surface that extends along the motor axis J2.

[0016] The motor shaft 21 extends across the motor chamber 81 and the gear chamber 82 of the housing 6. One end of the motor shaft 21 protrudes toward the gear chamber 82. A pinion gear 41 is fixed to the end of the motor shaft 21 that protrudes into the gear chamber 82.

[0017] The motor shaft 21 is rotatably supported by bearings 16 and 16A in the motor chamber 81. That is, the bearings 16 and 16A rotatably support the motor shaft 21. The bearing 16A supports the motor shaft 21 at the middle of the motor shaft 21. On the other hand, the bearing 16 supports the end of the motor shaft 21 on one axial side (+Y side).

[0018] The rotor core 24 is made of laminated silicon steel plates. The rotor core 24 is a cylindrical body extending along the axial direction. A plurality of rotor magnets (not shown) are fixed to the rotor core 24. The plurality of rotor magnets are arranged along the circumferential direction with their magnetic poles alternating.

[0019] The stator 30 surrounds the rotor 20 from the radially outer side. The stator 30 has a stator core 32, a coil 31, and an insulator (not shown) interposed between the stator core 32 and the coil 31. The stator 30 is held in a housing 6. The stator core 32 has a plurality of magnetic pole teeth (not shown) extending radially inward from the inner circumferential surface of the annular yoke. A coil wire is wound between the magnetic pole teeth. The coil wire wound around the magnetic pole teeth forms the coil 31.

[0020] <Power transmission mechanism> The power transmission mechanism 3 is housed in the gear chamber 82. The power transmission mechanism 3 is connected to the motor shaft 21. The power transmission mechanism 3 has a plurality of transmission shafts (an intermediate shaft 45 and an output shaft 55) and a plurality of gears (a pinion gear 41, a counter gear 42, a drive gear 43, and a ring gear 51) provided on the outer circumferential surfaces of the transmission shafts. The power transmission mechanism 3 transmits the power of the motor 2 by the plurality of gears.

[0021] The power transmission mechanism 3 has a reduction gear 4 and a differential gear 5. The reduction gear 4 has the function of reducing the rotational speed of the motor 2 and increasing the torque output from the motor 2 in accordance with the reduction ratio. The reduction gear 4 is connected to the motor shaft 21 of the motor 2. The reduction gear 4 transmits the torque output from the motor 2 to the differential gear 5. The differential gear 5 is a device for transmitting the torque output from the motor 2 to the wheels of the vehicle. When the vehicle turns, the differential gear 5 has the function of transmitting the same torque to a pair of output shafts 55 while absorbing the speed difference between the left and right wheels.

[0022] The reduction gear 4 has a pinion gear 41, an intermediate shaft 45, and a counter gear 42 and a drive gear 43 fixed to the intermediate shaft 45. Torque output from the motor 2 is transmitted to a ring gear 51 of the differential device 5 via the motor shaft 21 of the motor 2, the pinion gear 41, the counter gear 42, and the drive gear 43. The gear ratio of each gear, the number of gears, and the like can be changed in various ways depending on the required reduction ratio. The reduction gear 4 is a parallel-shaft gear type reducer in which the axes of the gears are arranged in parallel.

[0023] The pinion gear 41 is fixed to the outer peripheral surface of the motor shaft 21 of the motor 2. The pinion gear 41 rotates together with the motor shaft 21 about the motor axis J2.

[0024] The intermediate shaft 45 extends along an intermediate axis J4 that is parallel to the motor axis J2. The intermediate shaft 45 rotates about the intermediate axis J4. The intermediate shaft 45 is rotatably supported on the inner surface of the housing 6 via a bearing.

[0025] The counter gear 42 and the drive gear 43 are arranged side by side in the axial direction. The counter gear 42 and the drive gear 43 are provided on the outer circumferential surface of the intermediate shaft 45. The counter gear 42 and the drive gear 43 are connected via the intermediate shaft 45. The counter gear 42 and the drive gear 43 rotate about the intermediate axis J4. At least two of the counter gear 42, the drive gear 43, and the intermediate shaft 45 may be formed from a single member. The counter gear 42 meshes with the pinion gear 41. The drive gear 43 meshes with the ring gear 51 of the differential device 5.

[0026] The differential device 5 has a ring gear 51 and a pair of output shafts 55. The ring gear 51 rotates about a differential axis J5 that is parallel to the motor axis J2. Torque output from the motor 2 is transmitted to the ring gear 51 via the reduction gear 4. The pair of output shafts 55 extend along the axial direction. A side gear is connected to each end of the pair of output shafts 55, and a wheel is connected to each end of the pair of output shafts 55. The pair of output shafts 55 transmit the torque of the motor 2 to the road surface via the wheels.

[0027] <Housing> The housing 6 accommodates the motor 2 and the power transmission mechanism 3 therein. The housing 6 has a first wall portion (wall portion) 62 and a second wall portion 64 extending along a plane perpendicular to the axial direction. The first wall portion 62 is disposed on one axial side (+Y side) of the motor 2. The second wall portion 64 is disposed on the other axial side (-Y side) of the motor 2. The second wall portion 64 is also disposed between the motor 2 and the power transmission mechanism 3. A portion of the second wall portion 64 divides the storage space 80 within the housing 6 into a motor chamber 81 and a gear chamber 82.

[0028] The first wall portion 62 is provided with a first shaft passing hole 62f, a first opening 62a, a second opening 62b, a bearing holding portion 65, a static eliminator holding portion 68, and a cover fixing portion 69. The static eliminator holding portion 68 holds the static eliminator 9. The bearing holding portion 65 holds the bearing 16. An insulating member 70 is interposed between the bearing 16 and the bearing holding portion 65.

[0029] A cover 6A is fixed to the first wall portion 62. The cover 6A is fixed to a cover fixing portion 69. A sensor chamber 83 is provided between the first wall portion 62 and the cover 6A. The cover 6A covers the first shaft passing hole 62f, the first opening 62a, and the second opening 62b of the first wall portion 62 from one axial side (+Y side).

[0030] FIG. 2 is a plan view of the first wall portion 62 as seen from the motor chamber 81 side. The first shaft passing hole 62f, the first opening 62a, and the second opening 62b axially penetrate the first wall portion 62. One axial end of the motor shaft 21 passes through the first shaft passing hole 62f. The first opening 62a is provided for arranging, for example, a rotation sensor (not shown) that measures the rotation speed of the motor shaft 21 and a harness (not shown) for the rotation sensor. The second opening 62b is located below the first shaft passing hole 62f and the first opening 62a. In this embodiment, the second opening 62b is located directly below the motor axis J2. The second opening 62b is provided for returning oil O that has entered the sensor chamber 83 from the first shaft passing hole 62f or the first opening 62a to the motor chamber 81.

[0031] 1, the second wall portion 64 is provided with a second shaft passing hole 64f, a third opening 64g, and a bearing holding portion 65A. The bearing holding portion 65A holds the bearing 16A. An insulating member 70A is interposed between the bearing 16A and the bearing holding portion 65A.

[0032] The second shaft passing hole 64f and the third opening 64g axially penetrate the second wall portion 64. The motor shaft 21 passes through the second shaft passing hole 64f. The third opening 64g is provided near the bottom of the motor chamber 81. The oil O that has cooled the motor 2 inside the motor chamber 81 moves from the motor chamber 81 to the oil sump P in the gear chamber 82 via the third opening 64g.

[0033] The bearing retaining portion 65 of the first wall portion 62 and the bearing retaining portion 65A of the second wall portion 64 are both disposed on the motor axis J2. The housing 6 retains the bearing 16A in the bearing retaining portion 65A, and retains the bearing 16 in the bearing retaining portion 65. The specific configurations of the bearing retaining portions 65, 65A will be described in detail later.

[0034] A catch tank 93 is disposed within the gear chamber 82 of the housing 6. The catch tank 93 is open at the top. The catch tank 93 functions as a reservoir that temporarily stores oil. The oil O scooped up by the counter gear 42 accumulates in the catch tank 93.

[0035] <Static eliminator> The static eliminator 9 is held by the static eliminator holding portion 68 of the housing 6. The static eliminator 9 is annular and surrounds the motor shaft 21. In this embodiment, the static eliminator 9 is annular and centered on the motor axis J2. The static eliminator 9 surrounds the end of the motor shaft 21 on one axial side (+Y side) from the radial outside.

[0036] The static eliminator 9 has an annular base centered on the motor axis J2 and a brush portion provided around the entire radial inner edge of the base. The static eliminator 9 is fixed to the static eliminator holder 68 at the base. Therefore, the static eliminator 9 is in electrical contact with the housing 6 at the base. The brush portion of the static eliminator 9 is in contact with the outer peripheral surface of the motor shaft 21. That is, the brush portion of the static eliminator 9 is in electrical contact with the rotor 20. In this specification, "a certain object is in electrical contact with another object" means that an electric current can flow between the certain object and the other object.

[0037] According to this embodiment, the motor shaft 21 and the housing 6 are electrically connected via the static eliminator 9. Therefore, the current generated in the motor shaft 21 can be passed through the housing 6. This prevents current from flowing through the bearings electrically connected to the motor shaft 21, thereby preventing electrolytic corrosion from occurring in the bearings.

[0038] The static eliminator 9 of this embodiment has been described as passing a current directly from the motor shaft 21 to the housing 6. However, the static eliminator 9 can be effective as long as it is provided in a portion electrically connected to the motor shaft 21. That is, the static eliminator 9 may be provided on the motor shaft 21 or any one of the multiple transmission shafts (intermediate shaft 45 and output shaft 55). In this case, the static eliminator 9 electrically connects the shaft and the housing 6 to release the charge on the shaft to the housing 6.

[0039] The relative positions of the insulating member 70 and the static eliminator 9 in the drive device 1 will be described in more detail. In a typical motor, a high-frequency circulating current is generated in a closed circuit connecting the motor shaft, one bearing, the housing, the other bearing, and the motor shaft. Here, the one bearing is the bearing on the power transmission side, which corresponds to bearing 16A in this embodiment, and the other bearing corresponds to bearing 16.

[0040] In this embodiment, insulating members 70 and 70A are attached to the bearings 16 and 16A, respectively. This breaks the closed circuit and prevents the generation of circulating current. Furthermore, according to this embodiment, a static eliminator 9 is further provided to eliminate static electricity, thereby suppressing the potential difference generated in the closed circuit and preventing electrolytic corrosion from occurring in the bearings 16 and 16A.

[0041] The preferred position for attaching the static eliminator 9 varies depending on the position of the bearings to which the insulating members 70 and 70A are attached. In FIG. 1, the positions at which the insulating members 70 and 70A or the static eliminator 9 can be arranged are designated Position A, Position B, and Position C, respectively. Position A is the support position for the motor shaft 21 on one axial side (+Y side) of the motor 2. Position B is the support position for the motor shaft 21 on the other axial side (-Y side) of the motor 2. Position C is the support position for the transmission shafts (motor shaft 21, intermediate shaft 45, and output shaft 55) in the gear chamber 82. Although not shown in FIG. 1, Position C also includes a portion that supports one axial side (+Y side) of the intermediate shaft 45.

[0042] When the insulating member 70 is attached only to the position A, the current flowing through the motor shaft 21 is induced to the position B, so that the static eliminator 9 is preferably attached to the position B. When the insulating member 70 is attached only to the position B, the current flowing through the motor shaft 21 is induced to the position A, so that the static eliminator 9 is preferably attached to the position A. When the insulating member 70 is attached to positions A and B, the current flowing through the motor shaft 21 is induced toward the gear chamber 82, so it is preferable that the static eliminator 9 be attached to either position C.

[0043] <Oil> The oil O is contained inside the housing. The oil O is used to lubricate the reduction gear 4 and the differential gear 5. The oil O is also used to cool the motor 2. The oil O accumulates in a lower region (i.e., oil reservoir P) inside the gear chamber 82. Since the oil O functions as a lubricating oil and a cooling oil, it is preferable to use oil equivalent to low-viscosity automatic transmission lubricating oil (ATF: Automatic Transmission Fluid).

[0044] 1, the oil O circulates in an oil passage 90 in the drive device 1. The oil passage 90 is a path for supplying the oil O from an oil reservoir P to the motor 2.

[0045] In this specification, the term "oil passage" refers to a path through which the oil O circulates in the accommodation space 80. Therefore, the term "oil passage" is a concept that includes not only a "flow path" that forms a steady flow of oil in one direction, but also a path that temporarily retains oil (for example, one that functions as a reservoir such as a catch tank) and a path through which oil drips.

[0046] The oil passage 90 is configured to straddle the motor chamber 81 and the gear chamber 82 of the accommodation space 80. The oil passage 90 is a path for the oil O that guides the oil O from the oil sump P through the motor 2 and back to the oil sump P. The oil passage 90 has a first oil passage 91 and a second oil passage 92.

[0047] The first oil passage 91 and the second oil passage 92 are both paths that supply oil O from the oil reservoir P to the motor 2 and then collect the oil back into the oil reservoir P. In the first oil passage 91 and the second oil passage 92, the oil O drips from the motor 2 and accumulates in a lower region within the motor chamber 81. The oil O that has accumulated in the lower region of the motor chamber 81 moves to the lower region of the gear chamber 82 (that is, the oil reservoir P) through the third opening 64g.

[0048] In the first oil passage 91, the oil O is scooped up from the oil reservoir P by the counter gear 42 and led to the catch tank 93. A portion of the oil O scooped up by the counter gear 42 is led to the bearings to enhance the lubrication of the bearings. Another portion of the oil O scooped up by the counter gear 42 falls onto each gear in the gear chamber 82 from above and is supplied to the tooth surfaces of each gear.

[0049] A portion of the oil O accumulated in the catch tank 93 passes through the first oil introduction passage 68b and is supplied to the inside of the motor shaft 21. Another portion of the oil O accumulated in the catch tank 93 is supplied to the bearing in the gear chamber 82.

[0050] Centrifugal force is applied to the oil O supplied to the hollow portion 22 of the motor shaft 21 as the rotor 20 rotates. The oil O continuously splashes outward in the inclined direction from holes provided in the rotor 20, cooling the stator 30. Upon reaching the stator 30, the oil O drips downward while absorbing heat from the stator 30, and accumulates in a lower region within the motor chamber 81. The oil O accumulated in the lower region within the motor chamber 81 moves to the gear chamber 82 via a third opening 64g provided in the second wall portion 64.

[0051] A pump 96, a cooler 97, and a supply pipe 95 are provided in the second oil passage 92. The pump 96 pumps the oil O through the second oil passage 92. The cooler 97 cools the oil O passing through the second oil passage 92.

[0052] The supply pipe 95 is disposed in the upper region of the motor chamber 81. The supply pipe 95 is disposed directly above the motor 2. That is, the supply pipe 95 is disposed above the motor 2 inside the housing 6. The supply pipe 95 extends along the axial direction. The supply pipe 95 is connected to the first wall portion 62 and the second wall portion 64. The supply pipe 95 is disposed above the motor 2 inside the motor chamber 81. The supply pipe 95 is provided with a discharge hole 95a that opens toward the motor 2. That is, the supply pipe 95 is provided with a discharge hole 95a that discharges the oil O.

[0053] In the present embodiment, the oil supply unit is provided as a pipe-shaped supply pipe 95 through which the oil O flows. However, the oil supply unit may have other configurations. For example, the oil supply unit may be a trough-shaped unit that stores the oil O and drips the oil from a discharge hole provided at the bottom.

[0054] In the second oil passage 92, the oil O is sucked up by a pump 96 and cooled by a cooler 97 before reaching the supply pipe 95. The oil O flowing through the supply pipe 95 is discharged toward the motor 2 from a discharge hole 95a provided in the supply pipe 95. The oil O discharged from the supply pipe 95 is supplied to the motor 2 from above the motor 2. A portion of the oil O discharged from the supply pipe 95 is supplied to the bearings 16, 16A. Here, the paths through which the oil discharged from the discharge hole 95a of the supply pipe 95 reaches the bearing 16 are referred to as a guide path 94, a first path 98, and a second path 99, in order from the upstream side. That is, the oil passage 90 has the guide path 94, the first path 98, and the second path 99.

[0055] The oil O supplied to the motor 2 flows along the outer peripheral surface of the stator 30, absorbing heat from the stator 30 and cooling the motor 2. The oil O that flows along the outer peripheral surface of the stator 30 drips downward and accumulates in a lower region within the motor chamber 81. The oil O in the second oil passage 92 merges with the oil O in the first oil passage 91 in the lower region within the motor chamber 81. The oil O that has accumulated in the lower region within the motor chamber 81 moves to the lower region within the gear chamber 82 (i.e., oil reservoir P) via the third opening 64g.

[0056] Here, the guide path 94 will be described with reference to Fig. 2. The first path 98 and the second path 99 will be described in detail later together with the holding structure of the bearing 16.

[0057] A plurality of ribs 62d are provided on a surface 62c of the first wall portion 62 facing the motor chamber 81. The plurality of ribs 62d protrude toward the other axial side (-Y side). The plurality of ribs 62d extend radially outward from the bearing holding portion 65. The plurality of ribs 62d are arranged side by side in the circumferential direction. The circumferential distance between the ribs 62d arranged side by side in the circumferential direction becomes closer as one moves from the radially outer side to the radially inner side.

[0058] The guide path 94 is provided between circumferentially adjacent ribs 62d. The ribs 62d arranged on one circumferential side and the other circumferential side of the guide path 94 are referred to as the first rib 62da and the second rib 62db, respectively. The first rib 62da and the second rib 62db are located above the bearing holder 65. That is, the first rib 62da and the second rib 62db extend upward from the bearing holder 65. The second rib 62db extends parallel to the vertical direction. The first rib 62da extends at a slight incline with respect to the vertical direction. More specifically, the first rib 62da inclines in a direction away from the second rib 62db as it extends upward. An inlet of the first path 98 is provided between the connection portion of the first rib 62da with the bearing holder 65 and the connection portion of the second rib 62db with the bearing holder 65.

[0059] The oil O discharged from the supply pipe 95 hits the side surface of the first rib 62da. The side surface of the first rib 62da that the oil O hits faces the second rib 62db. The oil O that reaches the first rib 62da flows downward along the side surface of the first rib 62da and reaches the first path 98 provided in the bearing holder 65. As described above, the guide path 94 is formed by the side surface of the rib 62d of the first wall portion 62 and is a path that guides the oil O discharged from the supply pipe 95 to the inlet of the first path 98. As will be described later, the first path 98 is disposed inside the through-hole 66a of the bearing holder 65. According to this embodiment, the guide path 94 guides the oil O dripping from the discharge hole 95a to the through-hole 66a located below the discharge hole 95a of the supply pipe 95. According to this embodiment, the oil O discharged from the discharge hole 95a can be smoothly guided to the first path 98.

[0060] <Bearing holder and insulating member> Next, a description will be given of the configuration of the bearing holder 65 and the insulating member 70. As described above, the bearing holder 65 holds the bearing 16. Here, a specific description will be given of the bearing holding portion 65 of the first wall portion 62 and the insulating member 70 held by the bearing holding portion 65. However, it is preferable that the bearing holding portion 65A and the insulating member 70A of the second wall portion 64 have a similar configuration.

[0061] Fig. 3 is a perspective view of the insulating member 70. Fig. 4 is a perspective view of the bearing holder 65 to which the insulating member 70 is attached. Fig. 5 is a cross-sectional view of the insulating member 70 and the bearing holder 65 taken along line VV in Fig. 4. Fig. 6 is a perspective view of the bearing holder 65 to which the insulating member 70 is attached, seen from a different direction than Fig. 4.

[0062] As shown in FIG. 4, the bearing holder 65 has a holder cylinder portion 66 and a holder bottom portion 67 . The retaining cylindrical portion 66 protrudes from the edge of the first shaft passing hole 62f toward the other axial side (-Y side). The retaining cylindrical portion 66 is cylindrical and has its center on the motor axis J2. The retaining cylindrical portion 66 holds the bearing 16 from the radially outer side.

[0063] The retaining cylindrical portion 66 is provided with a through-hole 66a that penetrates from the inside to the outside in the radial direction. In this embodiment, the through-hole 66a is a notch that opens at the end of the retaining cylindrical portion 66 on the other axial side (-Y side). In this embodiment, the through-hole 66a penetrates in the up-down direction. A supply pipe 95 that discharges oil O downward is arranged above the through-hole 66a. Oil O is supplied to the through-hole 66a from the supply pipe 95. As a result, the through-hole 66a functions as a first path 98 that guides oil O from the outside to the inside in the radial direction of the retaining cylindrical portion 66. In other words, the first path 98 is arranged inside the through-hole 66a.

[0064] The retaining bottom portion 67 extends radially inward from the end portion on one axial side (+Y side) of the retaining cylindrical portion 66. The inner edge of the retaining bottom portion 67 is circular, as viewed from the axial direction, with the motor axis J2 as its center. The retaining bottom portion 67 extends annularly along the circumferential direction of the motor axis J2. The retaining bottom portion 67 supports the bearing 16 from one axial side (+Y side).

[0065] 4 and 6, the retaining bottom 67 has a retaining bottom surface 67a, a first step (step) 67c, a second step (step) 67e, and a groove 67b. The retaining bottom surface 67a is the surface facing the other axial side (-Y side) of the retaining bottom 67. The first step 67c and the second step 67e protrude from the retaining bottom surface 67a toward the other axial side (-Y side). The first step 67c and the second step 67e have the same protruding height.

[0066] As shown in FIG. 2, the first step 67c and the second step 67e are disposed at different positions in the circumferential direction. The first step 67c and the second step 67e are each provided across the entire radial width of the retaining bottom 67. The first step 67c and the second step 67e each extend along the circumferential direction. In this embodiment, the dimension d1 of the first step 67c along the circumferential direction is greater than the dimension d2 of the second step 67e along the circumferential direction. The first step 67c is disposed radially inward of the first opening 62a. On the other hand, the second step 67e is disposed radially inward of the second opening 62b.

[0067] As shown in FIG. 4, the groove 67b is provided in the first step 67c. The groove 67b is disposed radially inside the through-hole 66a. The groove 67b extends along the radial direction. The radially outer end of the groove 67b is connected to the through-hole 66a. Oil O that has passed through the inside of the through-hole 66a flows in the groove 67b. Therefore, the groove 67b functions as a second path 99 that is connected to the first path 98 inside the through-hole 66a. In other words, the second path 99 is disposed inside the groove 67b.

[0068] As shown in FIG. 3 , the insulating member 70 of this embodiment is cup-shaped and has an insulating cylindrical portion 76 and an insulating bottom portion 77. The insulating member 70 is made of an insulating material. The insulating member 70 of this embodiment is made of an aluminum alloy whose surface has been anodized. By performing the anodization, an insulating coating made of aluminum oxide is provided on the surface of the aluminum alloy. Therefore, the aluminum alloy that has been anodized becomes insulating as a whole and can be used as the insulating member 70.

[0069] As shown in Fig. 4, the insulating cylindrical portion 76 has a cylindrical shape centered on the motor axis J2. The insulating cylindrical portion 76 extends in the axial direction along the retaining cylindrical portion 66 of the bearing retaining portion 65. The insulating cylindrical portion 76 is disposed between the inner peripheral surface of the retaining cylindrical portion 66 and the outer peripheral surface of the outer ring of the bearing 16. As a result, the insulating cylindrical portion 76 prevents direct contact between the retaining cylindrical portion 66 and the bearing 16 and prevents current from flowing through the bearing 16.

[0070] The insulating bottom portion 77 is located at the end of one axial side (+Y side) of the insulating cylindrical portion 76. The inner edge of the insulating bottom portion 77 is circular, when viewed from the axial direction, with its center on the motor axis line J2. The insulating bottom portion 77 extends annularly in the radial direction of the motor axis line J2. The insulating bottom portion 77 extends radially along the retaining bottom portion 67. The insulating bottom portion 77 is disposed between the retaining bottom portion 67 and the bearing 16. The insulating bottom portion 77 prevents direct contact between the insulating bottom portion 77 and the bearing 16, thereby preventing current from flowing through the bearing 16.

[0071] The outer peripheral surface of the insulating cylindrical portion 76 is provided with a large diameter portion 76p and a small diameter portion 76q. The large diameter portion 76p and the small diameter portion 76q are arranged side by side along the axial direction. The large diameter portion 76p is provided in a region of the outer peripheral surface of the insulating cylindrical portion 76 opposite the insulating bottom portion 77. The small diameter portion 76q is provided in a region of the outer peripheral surface of the insulating cylindrical portion 76 on the insulating bottom portion 77 side. The diameter of the small diameter portion 76q is smaller than the diameter of the large diameter portion 76p. The diameter of the large diameter portion 76p is approximately the same as the inner diameter of the holding cylindrical portion 66. On the other hand, the diameter of the small diameter portion 76q is smaller than the inner diameter of the holding cylindrical portion 66.

[0072] In the process of attaching the insulating member 70 to the bearing holder 65, the area of ​​the insulating bottom portion 77 of the insulating cylindrical portion 76 is likely to come into contact with the edge portion of the holder cylindrical portion 66. The insulating coating may be damaged by contact with the edge portion of another member.

[0073] According to this embodiment, a small diameter portion 76q is provided in an area of ​​the outer circumferential surface of the insulating cylindrical portion 76 that is likely to come into contact with other members. Because the small diameter portion 76q is smaller than the inner diameter of the retaining cylindrical portion 66, a gap is generated between the small diameter portion 76q and the inner circumferential surface of the retaining cylindrical portion 66 when the insulating member 70 is attached to the bearing retaining portion 65. According to this embodiment, even if the insulating coating of the small diameter portion 76q is damaged, electrical connection between the insulating member 70 and the bearing retaining portion 65 can be prevented.

[0074] In this embodiment, the corners 76r connecting the outer circumferential surface of the insulating cylindrical portion 76 and the insulating bottom portion have a smoothly curved shape. That is, the corners 76r are rounded. According to this embodiment, it is easier to form a coating (an anodized aluminum coating in this embodiment) of the insulating member 70 evenly on the corners 76r, compared to when the corners 76r have a sharp shape. Furthermore, when the insulating member 70 is press-fitted into the bearing holder 65, localized stress is less likely to be applied to a portion of the corners 76r, which can prevent damage to the insulating coating on the corners 76r.

[0075] As shown in FIG. 2, the insulating bottom portion 77 is provided with a first slit (slit) 77a and a second slit (slit) 77e. The first slit 77a and the second slit 77e extend in the radial direction. The first slit 77a and the second slit 77e each reach the entire radial width of the insulating bottom portion 77. The first slit 77a and the second slit 77e also extend in the circumferential direction. In this embodiment, the dimension of the first slit 77a in the circumferential direction is greater than the dimension of the second slit 77e in the circumferential direction.

[0076] As shown in Fig. 4, the first step 67c is inserted into the first slit 77a. That is, the first step 67c is inserted into the first slit 77a. The dimension of the first slit 77a along the circumferential direction is the same as or slightly larger than the dimension of the first step 67c along the circumferential direction. Therefore, the first step 67c functions as a rotation stopper for the insulating member 70.

[0077] As shown in FIG. 6, the second step 67e is inserted into the second slit 77e. That is, the second step 67e is inserted into the second slit 77e. The circumferential dimension of the second slit 77e is the same as or slightly larger than the circumferential dimension of the second step 67e. The second step 67e, together with the first step 67c, functions as a rotation stopper for the insulating member 70. Note that in this embodiment, the holding bottom 67 is provided with two steps (the first step 67c and the second step 67e), each of which functions as a rotation stopper, but either one of them can function as a rotation stopper.

[0078] As shown in FIG. 5, the first path 98 is disposed inside the notched through-hole 66a provided in the retaining cylindrical portion 66. The second path 99 is disposed inside the groove 67b provided in the retaining bottom portion 67 and the first slit 77a in the insulating bottom portion 77. The first path 98 and the second path 99 are disposed so as to be connected to each other. The oil O discharged from the discharge hole 95a (see FIG. 2) of the supply pipe 95 described above reaches the first path 98. The oil O passes through the first path 98 and reaches the radially inner side of the retaining cylindrical portion 66. The oil O further passes through the second path 99 and reaches the radially inner side of the insulating cylindrical portion 76, where it is supplied to the bearing 16. In this manner, the second path 99 connects the first path 98 and the bearing 16.

[0079] According to this embodiment, the insulating member 70 is used to ensure insulation between the housing 6 and the bearing 16, and oil O can be supplied to the bearing 16 disposed inside the insulating member 70 via the first path 98 and the second path 99. Therefore, according to this embodiment, electrolytic corrosion of the bearing 16 can be suppressed, and the bearing 16 can be provided with lubrication to operate smoothly.

[0080] According to this embodiment, the second path 99 passes through the groove 67b provided in the first step 67c of the retaining bottom 67. The first step 67c fits into the first slit 77a of the insulating bottom 77. Therefore, the second path 99 is disposed inside the first slit 77a. This allows the second path 99 to smoothly guide the oil O to the bearing 16 inside the insulating bottom 77 via the first slit 77a.

[0081] According to this embodiment, the second path 99 is disposed inside the groove portion 67b extending along the radial direction, which prevents the oil O from spreading and flowing out, and allows the oil O to be guided in a concentrated manner to the bearing 16, thereby more reliably improving the lubrication of the bearing 16.

[0082] As shown in FIG. 2, the first wall portion 62 extends radially outward from the bearing holder 65. The first wall portion 62 is provided with a first opening 62a located radially outward from the first step 67c and a second opening 62b located radially outward from the second step 67e. If the first wall portion 62 has the first opening 62a and the second opening 62b, stress concentration may occur near the first opening 62a and the second opening 62b, potentially reducing the strength and rigidity of the first wall portion 62. However, the bearing holder 65 has locally increased strength and rigidity by increasing the thickness of the holder bottom 67 at the first step 67c and the second step 67e.

[0083] According to this embodiment, the first wall portion 62 is reinforced by the first step portion 67c disposed radially inward of the first opening 62a and the second step portion 67e disposed radially inward of the second opening 62b, thereby preventing a local decrease in the strength and rigidity of the first wall portion 62 near the first opening 62a and the second opening 62b.

[0084] In this embodiment, the retaining bottom 67 has two steps 67c and 67e, and the first wall 62 is provided with two openings 62a and 62b. More specifically, the retaining bottom 67 has a first step 67c and a second step 67e as steps. The first wall 62 is also provided with a first opening 62a located radially outward from the first step 67c and a second opening 62b located radially outward from the second step 67e.

[0085] In this embodiment, the dimension d1 of the first step 67c along the circumferential direction is larger than the dimension d2 of the second step 67e along the circumferential direction. Furthermore, the dimension d3 of the first opening 62a along the circumferential direction is larger than the dimension d4 of the second opening 62b along the circumferential direction. That is, according to this embodiment, a relatively large step (first step 67c) is disposed inside the relatively large opening (first opening 62a). Furthermore, a relatively small step (second step 67e) is disposed inside the relatively small opening (second opening 62b). This allows the steps to be effectively disposed inside the portion where strength is reduced, thereby enabling the first wall portion 62 to be effectively disposed.

[0086] <Modification> The following describes the configurations of the insulating member and bearing holder of modified examples that can be employed in the above-described embodiment. In the description of each modified example, the same reference numerals are used to designate components that are the same as those in the already-described embodiment or modified example, and the description thereof will be omitted.

[0087] (Variation 1) FIG. 7 is a perspective view of an insulating member 170 and a bearing holder 165 of the first modification. Similar to the above-described embodiment, the bearing holder 165 has a holder tubular portion 66 and a holder bottom portion 167. The holder tubular portion 66 of this modified example has the same configuration as the above-described embodiment. A notched through-portion 66a is provided in the holder tubular portion 66. Similar to the above-described embodiment, the first path 98 through which the oil O passes is disposed inside the notched through-portion 66a provided in the holder tubular portion 66. Furthermore, unlike the above-described embodiment, the holder bottom portion 167 of this modified example does not have a step portion and has a uniform cross-sectional shape along the circumferential direction.

[0088] Similar to the above-described embodiment, the insulating member 170 is cup-shaped and has an insulating tubular portion 176 and an insulating bottom portion 177. The insulating tubular portion 176 is cylindrical and centered on the motor axis J2. The insulating tubular portion 176 extends in the axial direction along the retaining tubular portion 66. The insulating bottom portion 177 is located at the end of the insulating tubular portion 176 on one axial side (+Y side). The insulating bottom portion 177 extends in the radial direction along the retaining bottom portion 167.

[0089] A slit 177a is provided in the insulating bottom portion 177. The slit 177a extends in the radial direction. The slit 177a reaches the entire radial width of the insulating bottom portion 177. The slit 177a is disposed radially inside the through-hole 66a of the holding cylindrical portion 66. A second path 199 through which the oil O passes is disposed inside the slit 177a.

[0090] The first path 98 and the second path 199 are arranged to be connected to each other. The oil O passes through the first path 98 and reaches the radially inner side of the retaining cylindrical portion 66. The oil O then passes through the second path 199 and reaches the radially inner side of the insulating cylindrical portion 176, and is supplied to the bearing. In this manner, the second path 199 connects the first path 98 and the bearing. According to this modification, the oil O can be effectively supplied to the bearing through the first path 98 and the second path 199.

[0091] (Variation 2) 8 is a perspective view of a bearing holder 265 of Modified Example 2 and an insulating member 170 attached to the bearing holder 265. In this modified example, the insulating member 170 has the same configuration as that of Modified Example 1, and therefore a description thereof will be omitted.

[0092] Similar to the above-described embodiment, the bearing holder 265 has a holder tube 66 and a holder bottom 267. The holder tube 66 of this modification has the same configuration as the above-described embodiment. The holder tube 66 is provided with a notched through-portion 66a.

[0093] Unlike the above-described embodiment, the retaining bottom portion 267 of this modified example does not have a step portion. The retaining bottom portion 267 has a retaining bottom surface 267a and a groove portion 267b. The retaining bottom surface 267a is a surface facing the other axial side (-Y side) of the retaining bottom portion 267. The groove portion 267b is provided on the retaining bottom surface 267a. The groove portion 267b extends in the radial direction. The radially outer end of the groove portion 267b is connected to the through portion 66a. When the insulating member 170 is attached to the bearing retaining portion 265, the groove portion 267b overlaps with the slit 177a when viewed from the axial direction.

[0094] In this modified example, the second path 299 through which the oil O passes is disposed inside the slit 177a and the groove portion 267b. The first path 98 and the second path 299 are disposed so as to be connected to each other. The oil O passes through the first path 98 and reaches the radially inner side of the retaining cylindrical portion 66. The oil O then passes through the second path 299 and reaches the radially inner side of the insulating cylindrical portion 176, and is supplied to the bearing. In this manner, the second path 299 connects the first path 98 and the bearing. According to this modified example, the oil O can be effectively supplied to the bearing through the first path 98 and the second path 299.

[0095] (Variation 3) 9 is a perspective view of a bearing holder 365 of Modified Example 3 and an insulating member 170 attached to the bearing holder 365. In this modified example, the insulating member 170 has the same configuration as that of Modified Example 1, and therefore a description thereof will be omitted.

[0096] Similar to the above-described embodiment, the bearing holder 365 has a holder tube 66 and a holder bottom 367. The holder tube 66 of this modification has the same configuration as the above-described embodiment. The holder tube 66 is provided with a notched through-portion 66a.

[0097] The holding bottom portion 367 of this modified example has a holding bottom surface 367a, a step portion 367c, and a groove portion 367b. The holding bottom surface 367a is a surface facing the other axial side (-Y side) of the holding bottom portion 367. The step portion 367c protrudes from the holding bottom surface 367a toward the other axial side (-Y side). The step portion 367c is provided across the entire radial width of the holding bottom surface 367a. The step portion 367c is inserted into the slit 177a of the insulating member 170. As a result, the step portion 367c functions as a rotation stopper for the insulating member 170.

[0098] The groove 367b is provided in the step portion 367c. The groove 367b is disposed radially inside the through portion 66a. The groove 367b extends along the radial direction. The radially outer end of the groove 367b is connected to the through portion 66a. The second path 399 is disposed inside the groove 367b.

[0099] In this modification, the second path 399 through which the oil O passes is disposed inside the slit 177a and the groove 367b. The first path 98 and the second path 399 are disposed so as to be connected to each other. The oil O passes through the first path 98 and reaches the radially inner side of the retaining tube portion 66. The oil O then passes through the second path 399 and reaches the radially inner side of the insulating tube portion 176, and is supplied to the bearing. In this manner, the second path 399 connects the first path 98 and the bearing. According to this modification, the oil O can be effectively supplied to the bearing through the first path 98 and the second path 399.

[0100] (Variation 4) FIG. 10 is a perspective view of an insulating member 470 and a bearing holder 465 of the fourth modification. Similar to the above-described embodiment, the bearing holder 465 has a holder tube 66 and a holder bottom 467. The holder tube 66 of this modified example has the same configuration as the above-described embodiment. A notched through-portion 66a is provided in the holder tube 66. Similar to the above-described embodiment, the first path 98 through which the oil O passes is disposed inside the notched through-portion 66a provided in the holder tube 66.

[0101] The retaining bottom 467 of this modified example does not have a step portion, unlike the above-described embodiment. The retaining bottom 467 has a retaining bottom surface 467a and a groove portion 467b. The retaining bottom surface 467a is a surface facing the other axial side (-Y side) of the retaining bottom 467. The groove portion 467b is provided on the retaining bottom surface 467a. The groove portion 467b extends in the radial direction. The radially outer end of the groove portion 467b is connected to the through portion 66a. A second path 499, through which the oil O passes, is arranged inside the groove portion 467b.

[0102] Similar to the above-described embodiment, the insulating member 470 is cup-shaped and includes an insulating tubular portion 476 and an insulating bottom portion 477. The insulating tubular portion 476 is cylindrical and centered on the motor axis J2. The insulating tubular portion 476 extends in the axial direction along the retaining tubular portion 66. The insulating bottom portion 477 is located at one axial end (+Y side) of the insulating tubular portion 476. The insulating bottom portion 477 extends in the radial direction along the retaining bottom portion 467. The insulating tubular portion 476 and the insulating bottom portion 477 of this modification do not have slits or through-holes. Therefore, the insulating tubular portion 476 and the insulating bottom portion 477 have a uniform cross-sectional shape along the circumferential direction. The insulating bottom portion 477 of this modification covers the groove portion 467b of the retaining bottom portion 467 from the other axial end (-Y side). This prevents oil O passing through the groove portion 467b from leaking out of the groove portion 467b.

[0103] According to this modification, the first path 98 and the second path 499 are arranged to be connected to each other. The oil O passes through the first path 98 and reaches the radially inner side of the retaining cylindrical portion 66. The oil O then passes through the second path 499 and reaches the radially inner side of the insulating cylindrical portion 476, and is supplied to the bearing. In this manner, the second path 499 connects the first path 98 and the bearing. According to this modification, the oil O can be effectively supplied to the bearing through the first path 98 and the second path 499.

[0104] (Variation 5) 11 is a cross-sectional view of a bearing holder 565 of Modification 5 and an insulating member 470 attached to the bearing holder 565. In this modification, the insulating member 470 has the same configuration as that of Modification 4, and therefore a description thereof will be omitted. Similar to the above-described embodiment, the bearing holder 565 has a holder tube 66 and a holder bottom 567. The holder tube 66 of this modified example has the same configuration as the above-described embodiment. A notched through-portion 66a is provided in the holder tube 66. Similar to the above-described embodiment, the first path 98 through which the oil O passes is disposed inside the notched through-portion 66a provided in the holder tube 66.

[0105] The retaining bottom portion 567 of this modified example has a retaining bottom surface 567a, an opposing bottom surface 567d, and a groove portion 567b. The retaining bottom surface 567a and the opposing bottom surface 567d face the other axial side (+Y side). The retaining bottom surface 567a and the opposing bottom surface 567d each extend circumferentially with a uniform radial width. The opposing bottom surface 567d is located radially inward and on one axial side (+Y side) of the retaining bottom surface 567a. Therefore, the retaining bottom surface 567a and the opposing bottom surface 567d are arranged in a stepped manner, with the one axial side (+Y side) positioned radially inward. The retaining bottom surface 567a contacts the insulating member 470. The retaining bottom surface 567a supports the insulating bottom portion 477 of the insulating member 470 from one axial side. On the other hand, the opposing bottom surface 567d does not contact the insulating bottom portion 477. The opposing bottom surface 567d is disposed opposite the insulating bottom portion 477 with a gap S in the axial direction therebetween.

[0106] The groove 567b is provided in the holding bottom surface 567a. The groove 567b extends radially. The bottom surface of the groove 567b is continuous with the opposing bottom surface 567d. The radially outer end of the groove 567b is continuous with the through portion 66a. The radially inner end of the groove 567b is continuous with the gap S between the opposing bottom surface 567d and the insulating bottom portion 477.

[0107] According to this modification, the second path 599 through which the oil O passes is arranged between the groove 567b and the insulating bottom 477, and between the opposing bottom surface 567d and the insulating bottom 477 (i.e., in the gap S). The first path 98 and the second path 599 are arranged to be connected to each other. The oil O passes through the first path 98 and reaches the groove 567b. Furthermore, the oil O passes through the second path 599 in the groove 567b and in the gap S and is supplied to the bearing 16. In this way, the second path 599 connects the first path 98 and the bearing 16. According to this modification, the oil O can be effectively supplied to the bearing 16 through the first path 98 and the second path 599.

[0108] (Variation 6) 12 is a perspective view of an insulating member 670 of Modification 6 and a bearing holder 165 to which the insulating member 670 is attached. The bearing holder 165 of this modification has the same configuration as Modification 1. That is, the bearing holder 165 has a retaining cylindrical portion 66 in which a through-hole 66a is provided, and a retaining bottom portion 667 having a uniform cross-sectional shape along the circumferential direction. A first path 98 through which the oil O passes is disposed inside the through-hole 66a.

[0109] Similar to the above-described embodiment, the insulating member 670 is cup-shaped and includes an insulating tubular portion 676 and an insulating bottom portion 677. The insulating tubular portion 676 is cylindrical and centered on the motor axis J2. The insulating tubular portion 676 extends in the axial direction along the retaining tubular portion 667. The insulating bottom portion 677 is located at the end of the insulating tubular portion 676 on one axial side (+Y side). The insulating bottom portion 677 extends in the radial direction along the retaining bottom portion 667.

[0110] An insulating penetrating portion 676a that penetrates radially is provided in the insulating tube portion 676. The insulating penetrating portion 676a overlaps the penetrating portion 66a when viewed radially. Therefore, the oil O that has passed through the first path 98 flows into the insulating penetrating portion 676a. That is, a second path 699 is disposed inside the insulating penetrating portion 676a.

[0111] The insulating penetrating portion 676a in this modified example is a circular hole when viewed from the radial direction. However, the insulating penetrating portion 676a is not limited to the configuration of this modified example as long as it penetrates the insulating cylindrical portion 676 in the radial direction. For example, the insulating penetrating portion 676a may have a notch shape that opens at the end of the insulating cylindrical portion 676 on the other axial side (-Y side).

[0112] The first path 98 and the second path 699 are arranged to be connected to each other. The oil O passes through the first path 98 and reaches the radially inner side of the retaining tube portion 66. Furthermore, the oil O passes through the second path 699 and reaches the radially inner side of the insulating tube portion 676, and is supplied to the bearing. In this manner, the second path 699 connects the first path 98 and the bearing. According to this modification, the oil O can be effectively supplied to the bearing through the first path 98 and the second path 699.

[0113] (Variation 7) FIG. 13 is a perspective view of an insulating member 770 and a bearing holder 765 of the seventh modification. Similar to the above-described embodiment, the bearing holder 765 has a holder tube 66 and a holder bottom 767. The holder tube 66 of this modified example has the same configuration as the above-described embodiment. A notched through-portion 66a is provided in the holder tube 66. Similar to the above-described embodiment, the first path 98 through which the oil O passes is disposed inside the notched through-portion 66a provided in the holder tube 66.

[0114] The retaining bottom portion 767 of this modified example has a retaining bottom surface 767a and a step portion 767c. The retaining bottom surface 767a is the surface facing the other axial side (-Y side) of the retaining bottom portion 767. The step portion 767c protrudes from the retaining bottom surface 767a toward the other axial side (-Y side). The step portion 767c is provided across the entire radial width of the retaining bottom surface 767a.

[0115] Similar to the above-described embodiment, insulating member 770 has insulating tubular portion 776 and insulating bottom portion 777. Insulating member 770 is C-shaped with slits 776a, 777a that connect insulating tubular portion 776 and insulating bottom portion 777. That is, the slit of insulating tubular portion 776 (hereinafter referred to as first slit 776a) and the slit of insulating bottom portion 777 (second slit 777a) are connected to each other.

[0116] The step 767c of the holding bottom 767 fits into the second slit 777a of the insulating bottom 777. This prevents the insulating member 770 from rotating relative to the bearing holding portion 765. That is, the step 767c functions as a stopper for the insulating member 770.

[0117] The first slit 776a of the insulating cylindrical portion 776 overlaps in the radial direction with the through portion 66a of the holding cylindrical portion 66. Therefore, the second path 799 through which the oil O passes is disposed inside the first slit 776a.

[0118] The first path 98 and the second path 799 are arranged to be connected to each other. The oil O passes through the first path 98 and reaches the radially inner side of the retaining tube portion 66. Furthermore, the oil O passes through the second path 799 in the first gap portion 776a and reaches the radially inner side of the insulating tube portion 776, and is supplied to the bearing. In this manner, the second path 799 connects the first path 98 and the bearing. According to this modification, the oil O can be effectively supplied to the bearing through the first path 98 and the second path 799.

[0119] Although the embodiments and modifications of the present invention have been described above, the configurations and their combinations in the embodiments are merely examples, and additions, omissions, substitutions, and other modifications of the configurations are possible without departing from the spirit of the present invention. Furthermore, the present invention is not limited to the embodiments. [Explanation of symbols]

[0120] 1...drive device, 2...motor, 3...power transmission mechanism, 6...housing, 9...static elimination device, 16, 16A...bearing, 21...motor shaft, 62...first wall portion (wall portion), 62a...first opening (opening), 62b...second opening (opening), 64...second wall portion (wall portion), 65, 65A, 165, 265, 365, 465, 565, 7 65...bearing holding portion, 66...holding tube portion, 66a...through portion, 67,167,267,367,467,567,667,767...holding bottom portion, 67a,267a,367a,467a,567a,767a...holding bottom surface, 67b,267b,367b,467b,567b...groove portion, 67c...first step portion (step portion), 67e...second The stepped portion (step portion), 70, 70A, 170, 470, 670, 770...insulating member, 76, 176, 476, 676, 776...insulating cylinder portion, 77, 177, 477, 677, 777...insulating bottom portion, 77a...first slit (slit), 77e...second slit (slit), 90...oil passage, 94...guide path, 95...supply pipe (oil supply part), 95a...discharge hole, 98...first path, 99, 199, 299, 399, 499, 599, 699, 799...second path, 177a...slit, 367c, 767c...step portion, 567d...opposing bottom surface, 676a...insulation penetration portion, 776a, 777a...slit portion, d1, d2, d3, d4...dimension, J, J2...motor axis, O...oil

Claims

1. a motor having a motor shaft that rotates about a motor axis; a bearing that rotatably supports the motor shaft; a housing that accommodates the motor therein and holds the bearing in a bearing holding portion; an insulating member interposed between the bearing and the bearing holder; oil contained inside the housing; an oil passage through which the oil flows, The bearing holding portion is a retaining cylindrical portion that retains the bearing from the radially outer side; a retaining bottom portion extending radially inward from one axial end of the retaining cylindrical portion, The insulating member is an insulating cylindrical portion extending axially along the holding cylindrical portion; an insulating bottom portion located at one axial end of the holding bottom portion and extending radially along the holding bottom portion, The retaining cylindrical portion is provided with a through-hole that penetrates from the inside to the outside in the radial direction, The oil passage is a first passage disposed inside the through-portion; a second path connecting the first path and the bearing, The holding bottom is a holding bottom surface facing the other axial side; a groove portion provided on the holding bottom surface and extending in a radial direction, the second path is disposed inside the groove; an opening on the other axial side of the groove portion is covered by the insulating bottom portion; Drive unit.

2. a motor having a motor shaft that rotates about a motor axis; a bearing that rotatably supports the motor shaft; a housing that accommodates the motor therein and holds the bearing in a bearing holding portion; an insulating member interposed between the bearing and the bearing holder; oil contained inside the housing; an oil passage through which the oil flows, The bearing holding portion is a retaining cylindrical portion that retains the bearing from the radially outer side; a retaining bottom portion extending radially inward from one axial end of the retaining cylindrical portion, The insulating member is an insulating cylindrical portion extending axially along the holding cylindrical portion; an insulating bottom portion located at one axial end of the holding bottom portion and extending radially along the holding bottom portion, The retaining cylindrical portion is provided with a through-hole that penetrates from the inside to the outside in the radial direction, The oil passage is a first passage disposed inside the through-portion; a second path connecting the first path and the bearing, The insulating bottom portion is provided with a slit extending in a radial direction, The second path is disposed inside the slit. Drive unit.

3. a motor having a motor shaft that rotates about a motor axis; a bearing that rotatably supports the motor shaft; a housing that accommodates the motor therein and holds the bearing in a bearing holding portion; an insulating member interposed between the bearing and the bearing holder; oil contained inside the housing; an oil passage through which the oil flows, The bearing holding portion is a retaining cylindrical portion that retains the bearing from the radially outer side; a retaining bottom portion extending radially inward from one axial end of the retaining cylindrical portion, The insulating member is an insulating cylindrical portion extending axially along the holding cylindrical portion; an insulating bottom portion located at one axial end of the holding bottom portion and extending radially along the holding bottom portion, The retaining cylindrical portion is provided with a through-hole that penetrates from the inside to the outside in the radial direction, The oil passage is a first passage disposed inside the through-portion; a second path connecting the first path and the bearing, The insulating bottom portion is provided with a slit extending in a radial direction, The holding bottom is a holding bottom surface facing the other axial side; a groove portion provided on the holding bottom surface, overlapping the slit when viewed from the axial direction, and extending in the radial direction; the second path is disposed inside the slit and the groove; Drive unit.

4. a motor having a motor shaft that rotates about a motor axis; a bearing that rotatably supports the motor shaft; a housing that accommodates the motor therein and holds the bearing in a bearing holding portion; an insulating member interposed between the bearing and the bearing holder; oil contained inside the housing; an oil passage through which the oil flows, The bearing holding portion is a retaining cylindrical portion that retains the bearing from the radially outer side; a retaining bottom portion extending radially inward from one axial end of the retaining cylindrical portion, The insulating member is an insulating cylindrical portion extending axially along the holding cylindrical portion; an insulating bottom portion located at one axial end of the holding bottom portion and extending radially along the holding bottom portion, The retaining cylindrical portion is provided with a through-hole that penetrates from the inside to the outside in the radial direction, The oil passage is a first passage disposed inside the through-portion; a second path connecting the first path and the bearing, The insulating bottom portion is provided with a slit extending in a radial direction, The holding bottom is a holding bottom surface facing the other axial side; a step portion that protrudes from the holding bottom surface toward the other axial direction and is inserted into the slit; a groove portion extending in a radial direction and provided in the step portion, The second path is disposed inside the groove. Drive unit.

5. a motor having a motor shaft that rotates about a motor axis; a bearing that rotatably supports the motor shaft; a housing that accommodates the motor therein and holds the bearing in a bearing holding portion; an insulating member interposed between the bearing and the bearing holder; oil contained inside the housing; an oil passage through which the oil flows, The bearing holding portion is a retaining cylindrical portion that retains the bearing from the radially outer side; a retaining bottom portion extending radially inward from one axial end of the retaining cylindrical portion, The insulating member is an insulating cylindrical portion extending axially along the holding cylindrical portion; an insulating bottom portion located at one axial end of the holding bottom portion and extending radially along the holding bottom portion, The retaining cylindrical portion is provided with a through-hole that penetrates from the inside to the outside in the radial direction, The oil passage is a first passage disposed inside the through-portion; a second path connecting the first path and the bearing, The holding bottom is a holding bottom surface facing the other axial side; an opposing bottom surface facing the other axial side and positioned radially inward and on one axial side of the holding bottom surface; a groove portion provided on the holding bottom surface and extending in a radial direction, the insulating member contacts the bottom holding surface, the second path is disposed between the groove and the insulating bottom, and between the opposing bottom surface and the insulating bottom; Drive unit.

6. a motor having a motor shaft that rotates about a motor axis; a bearing that rotatably supports the motor shaft; a housing that accommodates the motor therein and holds the bearing in a bearing holding portion; an insulating member interposed between the bearing and the bearing holder; oil contained inside the housing; an oil passage through which the oil flows, The bearing holding portion is a retaining cylindrical portion that retains the bearing from the radially outer side; a retaining bottom portion extending radially inward from one axial end of the retaining cylindrical portion, The insulating member is an insulating cylindrical portion extending axially along the holding cylindrical portion; an insulating bottom portion located at one axial end of the holding bottom portion and extending radially along the holding bottom portion, The retaining cylindrical portion is provided with a through-hole that penetrates from the inside to the outside in the radial direction, The oil passage is a first passage disposed inside the through-portion; a second path connecting the first path and the bearing, the insulating member is C-shaped and has a slit portion that is continuous with the insulating cylindrical portion and the insulating bottom portion. Drive unit.

7. The second path is disposed inside the gap. The drive device according to claim 6.

8. a motor having a motor shaft that rotates about a motor axis; a bearing that rotatably supports the motor shaft; a housing that accommodates the motor therein and holds the bearing in a bearing holding portion; an insulating member interposed between the bearing and the bearing holder; oil contained inside the housing; an oil passage through which the oil flows, The bearing holding portion is a retaining cylindrical portion that retains the bearing from the radially outer side; a retaining bottom portion extending radially inward from one axial end of the retaining cylindrical portion, The insulating member is an insulating cylindrical portion extending axially along the holding cylindrical portion; an insulating bottom portion located at one axial end of the holding bottom portion and extending radially along the holding bottom portion, The retaining cylindrical portion is provided with a through-hole that penetrates from the inside to the outside in the radial direction, The oil passage is a first passage disposed inside the through-portion; a second path connecting the first path and the bearing, The insulating bottom portion is provided with a slit extending in a radial direction, The holding bottom is a holding bottom surface facing the other axial side; a step portion that protrudes from the holding bottom surface toward the other axial side and is inserted into the slit, Drive unit.

9. the housing has a wall portion extending radially outward from the bearing retaining portion, The wall portion is provided with an opening located radially outward of the step portion. The drive device according to claim 8.

10. the holding bottom portion has a first step portion and a second step portion as the step portion, The wall portion has: a first opening located radially outward of the first step; a second opening located radially outward of the second step portion, a dimension of the first step portion along the circumferential direction is greater than a dimension of the second step portion along the circumferential direction; The dimension of the first opening along the circumferential direction is larger than the dimension of the second opening along the circumferential direction. The drive device according to claim 9.

11. an oil supply unit disposed inside the housing above the motor and having a discharge hole for discharging the oil; The through-hole is located below the discharge hole, The oil passage has a guide path that guides the oil dripping from the discharge hole to the through-hole. The drive device according to any one of claims 1 to 10.

12. a power transmission mechanism connected to the motor shaft, the power transmission mechanism includes a plurality of transmission shafts and a plurality of gears provided on outer peripheral surfaces of the transmission shafts, a static eliminator is provided on the motor shaft and any one of the plurality of transmission shafts, electrically connecting the shaft and the housing; A drive device according to any one of claims 1 to 11.

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