JP7028170B2 - motor - Google Patents

Description

The present invention relates to a motor.

Patent Document 1 discloses an end plate fixed to an end face of a rotor core and provided with an oil flow path extending in the radial direction. The oil in the oil flow path is scattered toward the stator located radially outside the rotor core by centrifugal force to cool the stator.

Japanese Patent No. 5772544

The conventional end plate has a problem that a part of the oil enters between the rotor and the stator because the opening of the oil flow path faces outward in the radial direction, which lowers the rotation efficiency of the rotor.

In view of the above problems, one aspect of the present invention is to provide a motor that controls the scattering direction of oil to effectively cool the stator.

One aspect of the motor of the present invention is a rotor that rotates about a motor shaft, and
The rotor is provided with a stator located on the outer side in the radial direction.
The rotor is
A shaft extending along the motor shaft and
A rotor core that surrounds the shaft from the outside in the radial direction,
A lid located at the axial end of the rotor core and
A plate-shaped end plate located between the rotor core and the lid,
Have,
The stator has a coil end that projects axially from the end of the rotor core.
The shaft has an inner peripheral surface extending in the axial direction and a hollow portion to which oil is supplied to the inside, and a communication hole extending in the radial direction to communicate the hollow portion and the outside of the shaft. Provided,
The end plate has a first surface facing the axial end surface of the rotor core and a second surface facing the opposite side of the first surface.
The end plate has a plate through hole extending in the axial direction, a first recess located on the first surface and extending radially inward from the plate through hole, and a plate through hole located on the second surface. A groove-shaped second recess extending radially outward from the hole is provided.
The first recess opens radially inside the end plate and connects to the communication hole.
The axially oriented opening of the first recess is covered by the rotor core and
The axially oriented opening of the second recess has a covering portion covered by the lid portion and an open portion not covered by the lid portion.
The open portion is located at the radial end of the second recess and is located.
The plate through hole is covered with the lid portion in the axial direction .

According to one aspect of the present invention, there is provided a motor that controls the scattering direction of oil to effectively cool the stator.

FIG. 1 is a conceptual diagram of a motor unit of one embodiment. FIG. 2 is a perspective view of the motor unit of one embodiment. FIG. 3 is a side view of the motor unit of one embodiment. FIG. 4 is a cross-sectional view of the motor unit taken along the line IV-IV of FIG. FIG. 5 is a cross-sectional view of the rotor of one embodiment. FIG. 6 is a plan view of the end plate. FIG. 7 is a cross-sectional view of the end plate along lines VII-VII of FIG. FIG. 8 is a cross-sectional view of the end plate of the first modification. FIG. 9 is a plan view of the end plate of the second modification. FIG. 10 is a cross-sectional view of the motor unit of one embodiment and is a diagram showing a second oil passage. FIG. 11 is a perspective view of the motor unit of the embodiment in which a part of the housing is omitted. FIG. 12 is a plan view of the second reservoir of one embodiment. FIG. 13 is a perspective view of the second reservoir of the modified example. FIG. 14 is a cross-sectional view of the motor unit of one embodiment and is a diagram showing an outline of a sub-reservoir. FIG. 15 is a front view of the partition wall opening of one embodiment. FIG. 16 is a graph showing the relationship between the height of the liquid level of the oil accumulated in the lower side of the motor chamber in the motor unit of one embodiment and the area of the first region. FIG. 17 is a front view of the partition wall opening of the modified example. FIG. 18 is a graph showing the relationship between the height of the oil level accumulated in the lower side of the motor chamber and the area of the first region in the motor unit provided with the partition wall opening of the modified example. FIG. 19 is a side view showing the arrangement of each gear located inside the gear chamber in the motor unit of one embodiment. FIG. 20 is a plan view of a parking mechanism that can be adopted in the motor unit of one embodiment. FIG. 21 is a partial cross-sectional view showing a disconnection mechanism of the motor unit of the modified example 1. FIG. 22 is a conceptual diagram showing a state in which the motor and the speed reducing device are connected by the disconnection mechanism. FIG. 23 is a conceptual diagram showing a state in which the motor and the speed reducing device are separated by the disconnection mechanism.

Hereinafter, the motor according to the embodiment of the present invention will be described with reference to the drawings. The scope of the present invention is not limited to the following embodiments, and can be arbitrarily changed within the scope of the technical idea of the present invention. Further, in the following drawings, in order to make each configuration easy to understand, the scale and number of each structure may be different from the actual structure.

In the following description, the direction of gravity will be defined and described based on the positional relationship when the motor unit 1 is mounted on a vehicle located on a horizontal road surface. Further, 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 a vertical direction (that is, a vertical direction), the + Z direction is the upper side (opposite the gravity direction), and the −Z direction is the lower side (gravity direction). Further, the X-axis direction is a direction orthogonal to the Z-axis direction and indicates the front-rear direction of the vehicle on which the motor unit 1 is mounted, the + X direction is the front of the vehicle, and the −X direction is the rear of the vehicle. However, the + X direction may be the rear of the vehicle, and the −X direction may be the front of the vehicle. The Y-axis direction is a direction orthogonal to both the X-axis direction and the Z-axis direction, and is the width direction (left-right direction) of the vehicle.

Unless otherwise specified in the following description, the direction parallel to the motor shaft J2 of the motor 2 (Z-axis direction) is simply referred to as "axial direction", and the radial direction centered on the motor shaft J2 is simply referred to as "radial direction". The circumferential direction around the motor shaft J2, that is, the circumference of the motor shaft J2 is simply referred to as the "circumferential direction". Further, in the following description, "planar view" means a state viewed from the axial direction. However, the above "parallel direction" also includes a substantially parallel direction. Further, the above-mentioned "orthogonal direction" includes a direction substantially orthogonal to each other.

Hereinafter, the motor unit (electric drive device) 1 according to an exemplary embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a conceptual diagram of the motor unit 1 of the embodiment. FIG. 2 is a perspective view of the motor unit 1. FIG. 3 is a side view of the motor unit 1. FIG. 4 is a cross-sectional view of the motor unit 1 along the line IV-IV of FIG. In FIG. 4, a part of the internal structure of the differential device 5 is omitted.

The motor 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), and an electric vehicle (EV), and is used as the power source thereof.

As shown in FIG. 1, the motor unit 1 includes a motor (main motor) 2, a speed reducing device 4, a differential device 5, a housing 6, an oil O, and an oil passage 90 that supplies the oil O to the motor 2. And. Further, the motor unit 1 may have a parking mechanism 7 as shown by a virtual line in FIG.

As shown in FIG. 1, the motor 2 includes a rotor 20 that rotates about a motor shaft J2 that extends in the horizontal direction, and a stator 30 that is located on the radial outer side of the rotor 20. The speed reducer 4 is connected to the rotor 20 of the motor 2. The differential device 5 is connected to the motor 2 via the speed reducer 4. Inside the housing 6, a storage space 80 for accommodating the motor 2, the speed reducing device 4, and the differential device 5 is provided. The oil O is used for lubricating the speed reducing device 4 and the differential device 5, and is also used for cooling the motor 2. The oil O collects in the area below the accommodation space 80 in the vertical direction. Since the oil O has the functions of a lubricating oil and a cooling oil, it is preferable to use an oil O equivalent to an automatic transmission fluid (ATF) having a low viscosity. The oil passage 90 is a path of the oil O that supplies the oil O to the motor 2 from the region below the accommodation space 80. The oil passage 90 has a first oil passage 91 and a second oil passage 92.

In addition, in this specification, "oil passage" means the route of oil O circulating in accommodation space 80. Therefore, the "oil passage" is not only the "flow path" that forms a steady flow of oil in one direction, but also the path that temporarily retains the oil (for example, the reservoir) and the oil drips. It is a concept that also includes routes.

<Housing>
The motor 2, the speed reducing device 4, and the differential device 5 are housed in the housing space 80 provided inside the housing 6. The housing 6 holds the motor 2, the speed reducer 4, and the differential device 5 in the accommodation space 80. The housing 6 has a partition wall 61c. The accommodation space 80 of the housing 6 is divided into a motor chamber 81 and a gear chamber 82 by a partition wall 61c. The motor 2 is housed in the motor chamber 81. The speed reducing device 4 and the differential device 5 are housed in the gear chamber 82.

An oil reservoir P in which the oil O is accumulated is provided in the lower region of the accommodation space 80. In the present embodiment, the bottom portion 81a of the motor chamber 81 is located above the bottom portion 82a of the gear chamber 82. Further, a partition wall opening 68 is provided in a region below the partition wall 61c that separates the motor chamber 81 and the gear chamber 82. The partition wall opening 68 communicates the motor chamber 81 and the gear chamber 82. The partition wall opening 68 moves the oil O accumulated in the lower region of the motor chamber 81 to the gear chamber 82. Therefore, in the present embodiment, the oil sump P is provided in the lower region of the gear chamber 82.

A part of the differential device 5 is immersed in the oil sump P. The oil O accumulated in the oil reservoir P is scooped up by the operation of the differential device 5, and a part of the oil O is supplied to the first oil passage 91 and a part of the oil O is diffused into the gear chamber 82. The oil O diffused in the gear chamber 82 is supplied to each gear of the speed reducing device 4 and the differential device 5 in the gear chamber 82, and the oil O is distributed to the tooth surface of the gear. The oil O used in the speed reducing device 4 and the differential device 5 is dropped and collected in the oil sump P located below the gear chamber 82. The capacity of the oil sump P in the accommodation space 80 is set so that a part of the bearing of the differential device 5 is immersed in the oil O when the motor unit 1 is stopped.

The housing 6 is made of, for example, aluminum die-cast. The housing 6 constitutes the outer frame of the motor unit 1. The housing 6 has a motor accommodating portion 61, a gear accommodating portion 62, and a closing portion 63. The gear accommodating portion 62 is located on the left side of the motor accommodating portion 61. The closing portion 63 is located on the right side of the motor accommodating portion 61.

The motor accommodating portion 61 has a cylindrical peripheral wall portion 61a that surrounds the motor 2 from the outside in the radial direction, and a side plate portion 61b located on one side in the axial direction of the peripheral wall portion 61a. The space inside the peripheral wall portion 61a constitutes the motor chamber 81. The side plate portion 61b has a partition wall 61c and a protruding plate portion 61d. The partition wall 61c covers the opening on one side in the axial direction of the peripheral wall portion 61a. In addition to the partition wall opening 68 described above, the partition wall 61c is provided with an insertion hole 61f through which the shaft 21 of the motor 2 is inserted. The side plate portion 61b has a partition wall portion 61c and a protruding plate portion 61d projecting radially outward with respect to the peripheral wall portion 61a. The protruding plate portion 61d is provided with a first axle passage hole 61e through which a drive shaft (not shown) that supports the wheels passes.

The closing portion 63 is fixed to the motor accommodating portion 61. The closing portion 63 closes the opening on the opposite side of the peripheral wall portion 61a in the axial direction. That is, the closing portion 63 closes the opening of the cylindrical motor accommodating portion 61. The closing portion 63 has a closing portion main body 63a and a lid member 63b. The closed portion main body 63a has a tubular protruding portion 63d that protrudes into the accommodating space 80 located inside the motor accommodating portion 61. The protrusion 63d extends along the inner peripheral surface of the peripheral wall portion 61a. Further, the closed portion main body 63a is provided with a window portion 63c penetrating in the axial direction. The lid member 63b closes the window portion 63c from the outside of the accommodation space 80.

The gear accommodating portion 62 is fixed to the side plate portion 61b of the motor accommodating portion 61. The gear accommodating portion 62 has a concave shape that opens toward the side plate portion 61b. The opening of the gear accommodating portion 62 is covered with the side plate portion 61b. The space between the gear accommodating portion 62 and the side plate portion 61b constitutes a gear chamber 82 accommodating the speed reducing device 4 and the differential device 5. The gear accommodating portion 62 is provided with a second axle passage hole 62e. The second axle passage hole 62e overlaps with the first axle passage hole 61e when viewed from the axial direction.

As shown in FIG. 3, the gear accommodating portion 62 has a first reservoir (reservoir) 93 and a shaft supply flow path 94. The first reservoir 93 is located on a surface of the gear accommodating portion 62 facing the gear chamber 82 in the axial direction, and extends along the axial direction. The first reservoir 93 receives the oil O scooped up by the differential device 5. The shaft supply flow path 94 extends from the bottom of the first reservoir 93 toward the shaft 21 of the motor 2. The shaft supply flow path 94 is a flow path for supplying the oil O received in the first reservoir 93 to the inside of the hollow portion 22 of the shaft 21.

<Reducer>
As shown in FIG. 4, the speed reducing device 4 has a function of reducing the rotation speed of the motor 2 and increasing the torque output from the motor 2 according to the reduction ratio. The speed reducing device 4 transmits the torque output from the motor 2 to the differential device 5.

The reduction gear 4 has a first gear (intermediate drive gear) 41, a second gear (intermediate gear) 42, a third gear (file null drive gear) 43, and an intermediate shaft 45. The torque output from the motor 2 is transferred to the ring gear (gear) 51 of the differential device 5 via the shaft 21, the first gear 41, the second gear 42, the intermediate shaft 45, and the third gear 43 of the motor 2. Be transmitted. The gear ratio of each gear, the number of gears, and the like can be variously changed according to the required reduction ratio. The speed reducer 4 is a parallel shaft gear type speed reducer in which the shaft cores of the gears are arranged in parallel.

The first gear 41 is provided on the outer peripheral surface of the shaft 21 of the motor 2. The first gear 41 rotates around the motor shaft J2 together with the shaft 21.

The intermediate shaft 45 extends along an intermediate shaft J4 parallel to the motor shaft J2. The intermediate shaft 45 has a cylindrical shape centered on the intermediate shaft J4. The intermediate shaft 45 rotates about the intermediate shaft J4. The intermediate shaft 45 is rotatably supported by a pair of intermediate shaft holding bearings 87. One of the pair of intermediate shaft holding bearings 87 is held on the surface of the partition wall 61c facing the gear chamber 82 side. The other of the pair of intermediate shaft holding bearings 87 is held by the gear accommodating portion 62.

The second gear 42 and the third gear 43 are provided on the outer peripheral surface of the intermediate shaft 45. The second gear 42 and the third gear 43 are connected via an intermediate shaft 45. The second gear 42 and the third gear 43 rotate about the intermediate shaft J4. The second gear 42 meshes with the first gear 41. The third gear 43 meshes with the ring gear 51 of the differential device 5. The third gear 43 is located on the partition wall 61c side with respect to the second gear 42. In this embodiment, the intermediate shaft 45 and the third gear 43 are a single member.

<Differential device>
The differential device 5 is a device for transmitting the torque output from the motor 2 to the wheels of the vehicle. The differential device 5 has a function of transmitting the same torque to the axles 55 of both the left and right wheels while absorbing the speed difference between the left and right wheels when the vehicle turns. The differential device 5 has a ring gear 51, a gear housing 57, a pair of pinion gears (not shown), a pinion shaft (not shown), and a pair of side gears (not shown).

The ring gear 51 rotates about a differential shaft J5 parallel to the motor shaft J2. The torque output from the motor 2 is transmitted to the ring gear 51 via the speed reducer 4. That is, the ring gear 51 is connected to the motor 2 via another gear. The ring gear 51 is fixed to the outer periphery of the gear housing 57.

The gear housing 57 accommodates a pair of pinion gears and a pair of side gears. When torque is transmitted to the ring gear 51, the gear housing 57 rotates around the differential shaft J5 together with the ring gear 51.
A pair of pinion gears are bevel gears that face each other. The pair of pinion gears are supported by the pinion shaft.
The pair of side gears are bevel gears that mesh at right angles to the pair of pinion gears. Each pair of side gears has a fitting portion. Axles are fitted to the fitting portions. A pair of axles fitted to different fitting portions rotate around the differential shaft J5 with the same torque.

<Motor>
As shown in FIG. 4, the motor 2 is an inner rotor type motor including a stator 30 and a rotor 20 rotatably arranged inside the stator 30. The rotor 20 rotates by supplying electric power to the stator 30 from a battery (not shown). The torque of the motor 2 is transmitted to the differential device 5 via the speed reducing device 4.

(Stator)
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 the housing 6.

The stator core 32 has a plurality of magnetic pole teeth (not shown) in the radial direction from the inner peripheral surface of the annular yoke. The stator core 32 of the present embodiment has 48 slots formed between the magnetic pole teeth. A coil 31 is formed by winding a coil wire between the magnetic pole teeth.

The coil 31 has a coil end 31a projecting from the axial end face of the stator core 32. That is, the stator 30 has a coil end 31a. The coil end 31a projects axially from the end of the rotor core 24 of the rotor 20. The coil end 31a projects on both sides in the axial direction with respect to the rotor core 24.

(Rotor)
The rotor 20 includes a shaft (motor shaft) 21, a rotor core 24, a rotor magnet (permanent magnet) 25, a pair of plate-shaped end plates 26, a nut 29, and a washer (cover) 28.

(shaft)
The shaft 21 extends about a motor shaft J2 extending horizontally and in the width direction of the vehicle (direction orthogonal to the traveling direction of the vehicle). The shaft 21 has a first shaft portion 21A and a second shaft portion 21B coaxially connected to each other.

The shaft 21 is a hollow shaft provided with a hollow portion 22 having an inner peripheral surface extending along the motor shaft J2 inside. The hollow portion 22 includes a first hollow portion 22A located inside the first shaft portion 21A and a second hollow portion 22B located inside the second shaft portion 21B. The first hollow portion 22A and the second hollow portion 22B are aligned along the axial direction and communicate with each other.

The first shaft portion 21A is arranged in the motor chamber 81 of the accommodation space 80. The first shaft portion 21A is located inside the stator 30 in the radial direction and penetrates the rotor core 24 along the motor shaft J2. The first shaft portion 21A has a first end portion 21e located on the output side (that is, the speed reducing device 4 side) and a second end portion 21f located on the opposite side thereof.

The first shaft portion 21A is rotatably supported by a pair of first bearings 89. The pair of first bearings 89 support the first end 21e and the second end 21f of the first shaft portion 21A. One of the pair of first bearings 89 is held by the closing portion 63. The other of the pair of first bearings 89 is held on the surface of the partition wall 61c facing the motor chamber 81 side.

FIG. 5 is a cross-sectional view of the rotor 20. In FIG. 5, the second shaft portion 21B is illustrated by a virtual line.
The first shaft portion 21A is provided with a pair of communication holes 23. The communication hole 23 extends in the radial direction to communicate the outside of the shaft 21 with the hollow portion 22. That is, the shaft 21 is provided with a pair of communication holes 23. The pair of communication holes 23 are arranged along the axial direction. In the present specification, the hole from the outer peripheral surface of the shaft 21 to the outer peripheral surface through the hollow portion is referred to as one communication hole 23.

On the outer peripheral surface of the first shaft portion 21A, a flange portion (cover portion) 21c and a screw portion 21d arranged along the axial direction are provided. That is, a flange portion 21c and a screw portion 21d are provided on the outer peripheral surface of the shaft 21. The rotor core 24 is located between the flange portion 21c and the threaded portion 21d in the axial direction. A nut 29 is fastened to the screw portion 21d.

As shown in FIG. 4, the second shaft portion 21B is located coaxially with the first shaft portion 21A. The second shaft portion 21b has a third end portion 21g located on the side of the first shaft portion 21A and a fourth end portion 21h located on the opposite side thereof. The second shaft portion 21B is connected to the first end portion 21e of the first shaft portion 21A at the third end portion 21g.

The second shaft portion 21B is arranged in the gear chamber 82 of the accommodation space 80. The third end portion 21g of the second shaft portion 21B projects toward the motor chamber 81 side through the insertion hole 61f provided in the partition wall 61c and is connected to the first shaft portion 21A. A first gear 41 is provided on the outer peripheral surface of the second shaft portion 21B. The first gear 41 is a part of the speed reducing device 4. The first gear 41 transmits the output of the meshing shaft 21 with the second gear 42 to the second gear.

The second shaft portion 21B is rotatably supported by a pair of second bearings 88. One of the pair of second bearings 88 is held on the surface of the partition wall 61c facing the gear chamber 82 side. The other of the pair of second bearings 88 is held by the gear accommodating portion 62.

The hollow portion 22 opens in the axial direction at the second end portion 21f of the first shaft portion 21A and the fourth end portion 21h of the second shaft portion 21B. Oil O is supplied to the hollow portion 22 from the opening of the fourth end portion 21h. The oil O supplied to the hollow portion 22 flows from the fourth end portion 21h side toward the second end portion 21f side. The oil O supplied to the hollow portion 22 flows out to the outside of the shaft 21 through the communication hole 23.
In the following description, the fourth end portion 21h side may be referred to as the flow direction upstream side of the hollow portion 22, and the second end portion 21f side may be referred to as the flow direction downstream side of the hollow portion 22.

As shown in FIG. 5, the first hollow portion 22A includes a first region 22p having a different inner peripheral surface diameter, a second region (small diameter hollow portion) 22q, and a third region (large diameter hollow portion) 22r. Have. The diameters of the inner peripheral surfaces of the first region 22p, the second region 22q, and the third region 22r increase in this order. That is, the second region 22q has a larger inner diameter than the first region 22p, and the third region 22r has a larger inner diameter than the first region 22p and the third region 22r. The first region 22p, the second region 22q, and the third region 22r are arranged in this order from the downstream side to the upstream side in the flow direction. The first region 22p is located on the second end 21f side. The second region 22q is located between the first region 22p and the third region 22r in the axial direction. The third region 22r is located on the side of the first end portion 21e. That is, the third region 22r is located on the second shaft portion 21B side of the second region 22q.

One of the pair of communication holes 23 on the upstream side in the flow direction opens in the third region 22r. Further, in the second region 22q, the other communication hole 23 on the downstream side in the flow direction of the pair of communication holes 23 opens.

Further, the inner peripheral surface of the first hollow portion 22A is located between the first stepped surface 22s located between the first region 22p and the second region 22q, and between the second region 22q and the third region 22r. It has a second stepped surface (stepped surface) 22t. The first stepped surface 22s and the second stepped surface 22t face the second shaft portion 21B side. Further, the first stepped surface 22s and the second stepped surface 22t are inclined toward the upstream side in the flow direction toward the outer side in the radial direction.

The third end portion 21g of the second shaft portion 21B is inserted into the third region 22r of the first shaft portion 21A. A female spline 22e is provided in the third region 22r. On the other hand, a male spline 22g is provided on the outer peripheral surface of the third end portion 21g of the second shaft portion 21B. The female spline 22e and the male spline 22g fit together. As a result, the first shaft portion 21A and the second shaft portion 21B are connected.

A gap is provided between the end surface of the second shaft portion 21B facing the first shaft portion 21A side (that is, the end surface of the third end portion 21g) and the second stepped surface 22t. The gap between the end surface of the third end portion 21g and the second stepped surface 22t constitutes a concave groove 22u on the inner peripheral surface of the hollow portion 22. That is, a concave groove 22u extending along the circumferential direction is provided on the inner peripheral surface of the hollow portion 22, and the concave groove 22u is the end surface of the third end portion 21g of the second shaft portion 21B and the third region. It is composed of an inner peripheral surface of 22r and a second stepped surface 22t.

Of the pair of communication holes 23, one of the communication holes 23 located on the upstream side in the flow direction of the oil O opens in the hollow portion 22 in the concave groove 22u. Centrifugal force is applied to the oil O supplied into the hollow portion 22 as the shaft 21 rotates. Since the concave groove 22u is provided on the inner peripheral surface of the hollow portion 22, the oil O collects in the concave groove 22u due to the centrifugal force. According to the present embodiment, since the communication hole 23 opens in the concave groove 22u, the oil O accumulated in the concave groove 22u can be efficiently guided to the communication hole 23.

According to the present embodiment, the oil O can be stored by using the gap of the connecting portion between the first shaft portion 21A and the second shaft portion 21B as the concave groove 22u. Therefore, it is not necessary to perform special processing to provide the concave groove 22u for storing the oil O.

When a plurality of communication holes 23 arranged along the axial direction are provided, the oil O easily flows into the communication holes 23 located on the downstream side in the flow direction of the oil O, and flows into the communication holes 23 on the upstream side in the flow direction of the oil O. Oil O may be insufficient. According to the present embodiment, since the communication hole 23 located on the upstream side in the flow direction opens in the concave groove 22u, the oil O can be sufficiently flowed into the communication hole 23 located on the upstream side in the flow direction.

According to the present embodiment, the diameter of the hollow portion 22 gradually decreases from the upstream side to the downstream side in the flow direction. As a result, the oil O can be easily distributed from the upstream side to the downstream side of the hollow portion 22. Further, one of the pair of communication holes 23 on the upstream side opens in the third region 22r, and the other on the downstream side opens in the second region 22q. That is, the opening of the communication hole 23 on the downstream side is provided in a region where the diameter of the hollow portion 22 is smaller than that of the opening of the communication hole 23 on the upstream side. Therefore, the oil O can be sufficiently flowed into the communication hole 23 located on the downstream side.

A part of the female spline 22e is located in the gap between the end surface of the third end portion 21g and the second stepped surface 22t. Therefore, on the inner peripheral surface of the hollow portion 22, convex portions and concave portions derived from the female spline 22e and arranged along the circumferential direction are provided. When the cross-sectional shape of the hollow portion is circular around the motor shaft, even if the shaft rotates, the oil O in the hollow portion may idle with respect to the shaft, and centrifugal force may not be applied to the oil O. .. On the other hand, by providing convex portions and concave portions arranged along the circumferential direction in the hollow portion 22, the oil O can be rotated with the rotation of the shaft 21, and centrifugal force is applied to the oil O in the hollow portion 22. be able to. As a result, the oil O can be smoothly guided to the communication hole 23.

According to the present embodiment, splines (male splines 22g and female splines 22e) that spline fit each other are provided on the outer peripheral surface of the second shaft portion 21B and the inner peripheral surface of the third region 22r. Further, a part of the spline (female spline 22e) of the third region 22r is located in the concave groove 22u. Therefore, the female spline 22e used for fitting can be used to apply centrifugal force to the oil O in the hollow portion 22. That is, it is not necessary to process the inner peripheral surface of the hollow portion 22 to provide an uneven shape in order to apply centrifugal force to the oil O.

(Rotor core)
The rotor core 24 is formed by laminating silicon steel plates. The rotor core 24 is a cylinder extending along the axial direction. The rotor core 24 has a pair of axial end faces 24a facing opposite sides in the axial direction and an outer peripheral surface 24b facing outward in the radial direction.

The rotor core 24 is sandwiched between the nut 29 and the flange portion 21c together with the pair of end plates 26. A washer 28 is interposed between the nut 29 and the end plate 26.

The rotor core 24 is provided with one fitting hole 24c located at the center in the axial direction and penetrating along the axial direction, a plurality of magnet holding holes 24d, and a plurality of core through holes 24e. The fitting hole 24c, the magnet holding hole 24d, and the core through hole 24e are opened in the pair of axial end faces 24a.

The fitting hole 24c has a circular shape centered on the motor shaft J2. The shaft 21 is inserted and fitted into the fitting hole 24c. Therefore, the rotor core 24 surrounds the shaft 21 from the outside in the radial direction. The fitting of the shaft 21 and the fitting hole 24c is a gap fitting. Therefore, the deformation of the rotor core 24 due to the fitting of the shaft 21 is suppressed. A protrusion (not shown) protruding inward in the radial direction is provided on the inner peripheral surface of the fitting hole 24c. This protrusion fits into a keyway (not shown) provided on the outer peripheral surface of the shaft 21. As a result, the relative rotation between the rotor core 24 and the shaft 21 is suppressed.

The plurality of core through holes 24e are arranged side by side along the circumferential direction. The core through hole 24e is located radially inside the magnet holding hole 24d. The core through hole 24e serves to flow the oil O between the pair of axial end faces 24a.

The plurality of magnet holding holes 24d are arranged side by side along the circumferential direction. The rotor magnet 25 is inserted into the magnet holding hole 24d. The magnet holding hole 24d holds the rotor magnet 25. That is, the rotor 20 of the present embodiment is an embedded type (IPM (interior permanent magnet)) in which a rotor magnet 25 is embedded inside the rotor core 24.

The rotor magnet 25 is a permanent magnet. The plurality of rotor magnets 25 are inserted into the plurality of magnet holding holes 24d arranged in the circumferential direction and fixed to the rotor core 24. The plurality of rotor magnets 25 are arranged along the circumferential direction.

(end plate)
FIG. 6 is a plan view of the end plate 26. FIG. 7 is a cross-sectional view of the end plate 26 along the line VII-VII of FIG. In addition, in FIG. 6 and FIG. 7, other members of the motor unit 1 are shown by virtual lines.

As shown in FIG. 6, the end plate 26 is circular in a plan view. The end plate 26 is a metal plate. The end plate 26 is provided with a circular central hole 26i that penetrates along the axial direction. A key portion 26q is provided on the inner peripheral surface of the central hole 26i. The key portion 26q fits into the key groove 21k provided on the shaft 21. Relative rotation of the end plate 26 and the shaft 21 is suppressed by fitting the key portion 26q and the key groove 21k.

As shown in FIG. 5, the end plate 26 has a first surface 26a and a second surface 26b. The first surface 26a faces the axial end surface 24a of the rotor core 24. The second surface 26b faces the opposite side of the first surface 26a.

The pair of end plates 26 are located on both sides of the rotor core 24 in the axial direction, respectively. The pair of end plates 26 each come into contact with the pair of axial end faces 24a of the rotor core 24. One of the pair of end plates 26 (first end plate 26A) is located between one axial end surface 24a of the rotor core 24 and the flange portion 21c. The other of the pair of end plates 26 (second end plate 26B) is located between the other axial end face 24a of the rotor core 24 and the washer 28. The end plate 26 comes into contact with the axial end surface 24a on the first surface 26a. Further, the end plate 26 comes into contact with the flange portion 21c or the washer 28 on the second surface 26b.

According to this embodiment, the rotor core 24 and the pair of end plates 26 are sandwiched between the flange portion 21c and the nut 29. As a result, the pair of end plates 26 are pressed against the axial end faces 24a of the rotor core 24 from both sides in the axial direction. A frictional force is generated at the contact portion between the first surface 26a of the end plate 26 and the axial end surface 24a of the rotor core 24, whereby the relative rotation between the rotor core 24 and the shaft 21 can be suppressed.
When the rotor core and the shaft are fixed by press fitting, the rotor core is deformed and the magnetic path passing through the rotor core is changed, resulting in a large iron loss. In particular, in a motor for driving a vehicle as in the present embodiment, since the driving force is large, it is necessary to secure a large press-fitting allowance, and the iron loss of the rotor core tends to be large. According to this embodiment, the rotor core 24 is fixed to the shaft 21 via the end plate 26. Therefore, the fitting of the fitting hole 24c of the rotor core 24 and the shaft 21 can be fitted in a gap, the deformation of the rotor core 24 can be suppressed, and the motor 2 with high efficiency can be provided.

As shown in FIG. 7, the first surface 26a is provided with a recess 26f and an inclined surface 26e that surrounds the recess 26f from the outside in the radial direction. The recess 26f has a circular shape centered on the motor shaft J2 in a plan view. The recess 26f has a recess bottom surface 26g and a recess inner peripheral surface 26h. The bottom surface 26g of the recess is a plane orthogonal to the motor shaft J2. The recess inner peripheral surface 26h is located between the recess bottom surface 26g and the inclined surface 26e. The concave inner peripheral surface 26h is inclined in a direction in which the concave portion 26f becomes shallower from the inner side in the radial direction to the outer side in the radial direction. A gap is provided between the recess 26f and the axial end surface 24a of the rotor core 24. Oil O collects in this gap and cools the axial end surface 24a of the rotor core 24.

The inclined surface 26e is provided in a region located on the outermost side in the radial direction on the first surface 26a, and extends along the circumferential direction. The inclined surface 26e is inclined toward the rotor core 24 side at an inclination angle θ toward the outer side in the radial direction. Here, the inclination angle θ is an angle formed by a plane orthogonal to the motor shaft J2 and the inclination surface 26e.

The end plate 26 comes into contact with the axial end surface 24a of the rotor core 24 on the inclined surface 26e of the first surface 26a. Since the inclined surface 26e inclines toward the rotor core 24 toward the radial outer side, the inclined surface 26e comes into contact with the axial end surface 24a in the region on the outermost radial direction. As a result, the frictional force generated by the contact between the inclined surface 26e and the axial end surface 24a can be generated as outward as possible in the radial direction. Further, the normal stress between the inclined surface 26e and the axial end surface 24a can be increased toward the outer side in the radial direction. As a result, the limit value of the static frictional force can be increased toward the outer side in the radial direction. The holding torque that suppresses the relative rotation between the end plate 26 and the rotor core 24 is proportional to the distance from the axis of rotation and the frictional force. Therefore, according to the present embodiment, the holding torque for suppressing the relative rotation between the end plate 26 and the rotor core 24 can be increased, and the rotor core 24 can be firmly held with respect to the end plate 26. In order to obtain such an effect, the inclination angle θ of the inclined surface 26e is preferably 0.1 ° or more and 5 ° or less.

Further, the end plate 26 of the present embodiment comes into contact with the axial end surface 24a of the rotor core 24 on the inclined surface 26e. Therefore, the contact position between the end plate 26 and the rotor core 24 can be stabilized. Therefore, it is possible to suppress variations in the transmission torque between the end plate 26 and the rotor core 24, and the rotor core 24 can be reliably fixed to the shaft 21.

Further, according to the present embodiment, by providing the inclined surface 26e on the end plate 26, even if the flatness of the contact portion between the end plate 26 and the axial end surface 24a of the rotor core 24 varies, the contact is surely made. be able to. As will be described later, an oil flow path 26t (see FIG. 5) is provided inside the inclined surface 26e in the radial direction. Generally, when oil enters between the rotor core and the stator, the rotational efficiency of the rotor core decreases. When the inclined surface 26e comes into contact with the axial end surface 24a of the rotor core 24, the oil O of the oil flow path 26t penetrates into the gap between the outer peripheral surface 24b of the rotor core 24 and the stator 30 from between the end plate 26 and the rotor core 24. It can be suppressed.
The inclined surface 26e may have a configuration in which the inclination angle changes toward the outer side in the radial direction. Further, the inclined surface 26e may be a curved surface whose inclination angle changes toward the outer side in the radial direction.

As shown in FIG. 5, the inclined surface 26e closes the opening of the magnet holding hole 24d of the rotor core 24. As a result, the rotor magnet 25 held inside the magnet holding hole 24d is prevented from popping out from the opening of the magnet holding hole 24d. As a result, it is possible to prevent a part of the rotor magnet 25 from entering the driving portion in the accommodating recess.

As shown in FIG. 7, the second surface 26b is provided with a flat surface portion 26c and a chamfered portion 26d located at the outer edge of the flat surface portion 26c. The flat surface portion 26c is orthogonal to the motor shaft J2. The chamfered portion 26d is inclined toward the first surface 26a toward the outer side in the radial direction.

As shown in FIG. 5, the end plate 26 has two sets of a plate through hole 26p, a first concave groove (first concave portion) 26j, and a second concave groove (second concave portion) 26k. It will be provided. Hereinafter, one set of the two sets of plate through holes 26p, the first concave groove 26j, and the second concave groove 26k will be described, but the other set also has the same configuration.

The plate through hole 26p extends along the axial direction. The first concave groove 26j is located on the first surface 26a. The first concave groove 26j extends radially inward from the opening of the plate through hole 26p. The first concave groove 26j opens radially inward on the inner peripheral surface of the central hole 26i. The second concave groove 26k is located on the second surface 26b. The second concave groove 26k extends radially outward from the opening of the plate through hole 26p. The second concave groove 26k opens radially outward in the chamfered portion 26d.

The axially oriented opening of the first concave groove 26j of the end plate 26 is covered by the axial end surface 24a of the rotor core 24. Further, the radial opening of the first concave groove 26j is connected to the communication hole 23 of the shaft 21.

The oil O supplied to the inside of the hollow portion 22 of the shaft 21 flows radially outward through the communication hole 23. Further, the oil O flows into the first concave groove 26j from the radial outer opening of the communication hole 23. Further, the oil O passes through the plate through hole 26p, flows toward the first surface 26a and the second surface 26b, and is discharged to the outside of the rotor 20 through the second concave groove 26k. As shown in FIG. 4, the coil end 31a of the stator 30 is provided on the radial outer side of the end plate 26. The oil O discharged to the outside of the rotor 20 is supplied to the coil end 31a to cool the coil end 31a.

The first concave groove 26j, the plate through hole 26p, and the second concave groove 26k of the end plate 26 function as an oil flow path 26t. That is, the oil flow path 26t is composed of a first concave groove 26j, a plate through hole 26p, and a second concave groove 26k. The pair of end plates 26 are each provided with an oil flow path 26t that communicates with the communication hole 23 and extends along the radial direction to open.

According to the end plate 26 of the present embodiment, the plate through hole 26p, the first concave groove 26j, and the second concave groove 26k form the oil flow path 26t. Therefore, according to the present embodiment, the oil flow path 26t can be configured by an inexpensive part (end plate 26) manufactured by mold molding.

A core through hole 24e communicates with the first concave groove 26j of the pair of end plates 26. That is, the core through hole 24e connects the first concave grooves 26j of the pair of end plates 26 to each other. In other words, the core through hole 24e connects the oil flow paths 26t of the pair of end plates 26 to each other. Further, at least a part of the opening of the core through hole is located radially outside the plate through hole 26p.

According to the present embodiment, since the core through hole 24e connects the first concave grooves 26j of the pair of end plates 26 to each other, a part of the oil O passing through the first concave groove 26j is made into the core through hole 24e. Can be shed. As a result, the rotor core 24 can be cooled from the inside by the oil O in the core through hole 24e. Further, the rotor magnet 25 held by the rotor core 24 can be cooled via the rotor core 24.

According to the present embodiment, the opening of the core through hole 24e is located radially outside the plate through hole 26p of the pair of end plates 26. As a result, the oil O can be stored inside the core through hole 24e by the centrifugal force of the rotor 20, and the oil O can be supplied to the first concave groove 26j of the end plates 26 on both sides from the core through hole 24e. Further, when the oil O is insufficient in the first concave groove 26j on one side of the pair of end plates 26, the oil O can be supplied from the other side through the core through hole 24e. Therefore, substantially the same amount of oil O can be discharged from each end plate 26 to the coil end 31a, and stable cooling of the coil 31 becomes possible.

As shown in FIG. 5, of the pair of end plates 26, one of the pair of end plates 26 sandwiched between the flange portion 21c and the rotor core 24 is used as the first end plate 26A, and is sandwiched between the nut 29 and the rotor core 24. The other is the second end plate 26B.

In the first end plate 26A, a part of the radial inner side of the plate through hole 26p is covered with the flange portion 21c. Further, in the first end plate 26A, the opening of the second concave groove 26k facing the axial direction as a whole faces the outer side in the axial direction. In other words, in the first end plate 26A, the axially oriented opening of the second concave groove 26k is entirely exposed when viewed from the axial direction. That is, the second concave groove 26k of the first end plate 26A communicates with the outside at the opening facing the axial direction. In the first end plate 26A, the second concave groove 26k functions as a part of the plate through hole 26p and the entire axially oriented opening as the first opening 26s released from the washer 28. In the first end plate 26A, the oil O that has passed through the plate through hole 26p is discharged from the first opening portion 26s.

A washer 28 is interposed between the second end plate 26B and the nut 29. In the second end plate 26B, a part of the radial inner side of the plate through hole 26p and the axially facing opening of the second concave groove 26k is covered with a washer 28. Of the openings of the second concave groove 26k facing in the axial direction, the portion covered by the washer 28 is referred to as a covering portion, and the portion not covered by the washer 28 is referred to as an opening portion. That is, in the second end plate 26B, the axially oriented opening of the second groove 26k has a covering portion covered by the washer 28 and a second opening portion 26r not covered by the washer. The second concave groove 26k of the second end plate 26B faces the axial outer side at the second open portion 26r located at the radial outer end of the second concave groove 26k. In other words, the second concave groove 26k of the second end plate 26B is exposed at the second open portion 26r when viewed from the axial direction. That is, the second concave groove 26k of the second end plate 26B communicates with the outside at the second open portion 26r. The second open portion 26r is located at the radial outer end of the second concave groove 26k. In the second end plate 26B, the oil O that has passed through the plate through hole 26p is discharged from the second opening portion 26r.

According to the first end plate 26A and the second end plate 26B of the present embodiment, the second surface 26b is provided with the second concave groove 26k, so that the second surface is provided through the plate through hole 26p. The oil O flowing to the 26b side can be moved radially outward along the second concave groove 26k. Therefore, the oil O can be stably flowed to the second open portion 26r, and the oil O can be stably supplied to the coil end 31a of the stator 30.

According to the present embodiment, the flange portion 21c or the washer 28 functions as a lid portion covering the axial opening with respect to the second concave groove 26k of the first end plate 26A and the second end plate 26B, respectively. do. That is, the rotor 20 has a pair of lids (flange 21c and washer 28) located at the axial end of the rotor core 24 via the end plate 26. The lid portion (flange portion 21c and washer 28) covers the axially oriented opening of the plate through hole 26p from the outside, so that the oil O flowing out from the plate through hole 26p to the second surface 26b side is second concave. It is guided to flow along the groove 26k. According to the present embodiment, the behavior of the oil O can be controlled by the lid portion (flange portion 21c and washer 28) to prevent the oil O from infiltrating between the rotor core 24 and the stator 30.

According to the second end plate 26B of the present embodiment, the axially oriented opening of the second concave groove 26k is partially covered by the washer 28 and faces the axially outward side at the second opening 26r. That is, in the region of the second concave groove 26k reaching the second open portion 26r, the oil O does not overflow in the axial direction, and the oil O can be reliably moved to the second open portion 26r. As a result, the oil O can be stably discharged from the second opening portion 26r, and the oil O can be stably supplied to the coil end 31a.

According to the present embodiment, the second concave groove 26k faces the axially outward side in the axial direction in the second open portion 26r located at the radial end portion. Therefore, the oil O that has passed through the second concave groove 26k can be scattered in the axial direction from the second open portion 26r. As a result, the oil O can be scattered toward the coil end 31a projecting axially from the end of the rotor core 24, and the coil 31 of the coil end 31a can be effectively cooled.

In the first end plate 26A of the present embodiment, the first opening portion 26s is provided over a part of the plate through hole 26p and the entire opening facing the axial direction. However, as shown by the virtual line in FIG. 5, the flange portion 21c may cover a part of the axially oriented opening of the second concave groove 26k. In this case, the first open portion 26s of the first end plate 26A is located at the radial outer end like the second open portion 26r of the second end plate 26B, and is the second. The same effect as that of the opening portion 26r can be obtained.

In the present embodiment, the end plate 26 is provided with a groove-shaped first concave groove 26j and a second concave groove 26k. However, even a recess that is not groove-shaped can achieve the above-mentioned certain effect. By providing the first concave groove 26j and the second concave groove 26k extending along the radial direction, the oil O can be smoothly guided along the radial direction.

(First modification of the end plate)
FIG. 8 is a cross-sectional view of the end plate 126 of the first modification that can be adopted in this embodiment. The components having the same embodiment as those described above will be described with reference to the same reference numerals.
The end plate 126 of the first modification has a first surface 126a facing the rotor core 24 and a second surface 126b facing away from the first surface 126a, as in the above embodiment. .. Further, the end plate 126 is provided with a pair of plate through holes 126p, a pair of first concave grooves 126j, and a pair of second concave grooves 126k. The plate through hole 126p extends axially. The first concave groove 126j is located on the first surface 126a. The first concave groove 126j extends radially inward from the plate through hole 126p. The second concave groove 126k is located on the second surface 126b. The second concave groove 126k extends radially outward from the plate through hole 126p. The axially oriented opening of the second concave groove 126k is partially covered by the lid 128 and faces the axially outward side of the opening 126r. Here, the lid portion 128 is a washer 28 or a flange portion 21c (see FIG. 5).

In this modification, the bottom of the second concave groove 126k is provided with an inclined surface 126u in which the depth of the second concave groove 126k becomes shallower toward the outer side in the radial direction. The inclined surface 126u overlaps with the open portion 126r when viewed from the axial direction. According to this modification, by providing the inclined surface 126u in the second concave groove 126k, it is possible to impart an axial component to the flow of the oil O. The oil O can be scattered in the axial direction, and the oil O can be effectively scattered toward the coil end 31a that protrudes in the axial direction from the end of the rotor core 24.

(Second modification of the end plate)
FIG. 9 is a plan view of the end plate 226 of the second modification that can be adopted in the present embodiment. The components having the same embodiment as those described above will be described with reference to the same reference numerals.
The end plate 226 of the second modification has a first surface 226a and a second surface 226b facing opposite to the first surface 226a, as in the above embodiment. Further, the end plate 226 has a pair of plate through holes 226p, a pair of first concave grooves 226j, and a pair of second concave grooves 226k. The plate through hole 226p extends axially. The first concave groove 226j is located on the first surface 226a. The first concave groove 226j extends radially inward from the plate through hole 226p. The second concave groove 226k is located on the second surface 226b. The second concave groove 226k extends radially outward from the plate through hole 226p. The axially oriented opening of the second concave groove 226k is partially covered by the lid portion 228 and faces the axially outward side at the opening portion 226r. Here, the lid portion 228 is a washer 28 or a flange portion 21c (see FIG. 5).

The second concave groove 226k is a groove extending along the radial direction. Further, when viewed from the axial direction, the extending direction of the second concave groove 226k is inclined with respect to the radial direction. Further, the second concave groove 226k is curved so as to increase the inclination angle with respect to the radial direction toward the outer side in the radial direction. According to this modification, since the second concave groove 226k is inclined in the radial direction, centrifugal force is applied to the oil O passing through the second concave groove 226k from the wall surface of the inclined second concave groove 226k. Can be granted. As a result, the speed of the oil O scattered from the open portion 226r can be increased, and the oil O can be reliably applied to the coil end 31a even when the distance to the coil end 31a is long.

The pair of second concave grooves 226k of this modification have different shapes when viewed from the axial direction. One of the second concave grooves 226kA of the pair of second concave grooves 226k is slightly curved with respect to the other second concave groove 226kB when viewed from the axial direction, and the inclination angle with respect to the radial direction is small. That is, according to the present embodiment, the extending directions of the plurality of second concave grooves 226kA and 226kB when viewed from the axial direction have different angles with respect to the radial direction. Therefore, the magnitudes of the centrifugal forces applied to the oil O by the pair of second concave grooves 226kA and 226kB are different from each other. The oil O scattered from one second concave groove 226 kA has a higher speed and is scattered in a farther range than the oil O scattered from the other second concave groove 226 kB. That is, according to this modification, the oil O can be scattered in different regions in the plurality of second concave grooves 226kA and 226kB, and the oil O can be applied to a wide range of the coil end 31a.

<Oil channel>
As shown in FIG. 1, the oil passage 90 is located inside the housing 6, that is, in the accommodation space 80. 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 of the oil O that guides the oil O from the oil sump P (that is, the region below the accommodation space 80) to the oil sump P again via the motor 2. The oil passage 90 has a first oil passage (oil passage) 91 passing through the inside of the motor 2 and a second oil passage (oil passage) 92 passing through the outside of the motor 2. The oil O cools the motor 2 from the inside and the outside in the first oil passage 91 and the second oil passage 92. The oil passage 90 constitutes an oil cooling mechanism.

Both the first oil passage 91 and the second oil passage 92 are routes for supplying oil O from the oil sump P to the motor 2 and collecting the oil O in the oil sump P again. In the first oil passage 91 and the second oil passage 92, the oil O drops from the motor 2 and accumulates in the lower region of the motor chamber. The oil O 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 partition wall opening 68.

A cooler 97 for cooling the oil O is provided in the path of the first oil passage 91. The oil O that has passed through the first oil passage 91 and has been cooled by the cooler 97 joins the oil O that has passed through the second oil passage 92 in the oil reservoir P. In the oil sump P, the oil O that has passed through the first oil passage 91 and the second oil passage 92 mixes with each other and heat exchange is performed. Therefore, the cooling effect of the cooler 97 arranged in the path of the first oil passage 91 can be exerted on the oil O passing through the second oil passage 92. According to the present embodiment, one cooler 97 provided in one of the first oil passage 91 and the second oil passage 92 is used to cool the oil O in both oil passages. ..

Generally, the cooler is placed in a flow path through which the liquid flows constantly. In order to cool the two oil passages, it is conceivable to arrange coolers in the flow paths included in the two oil passages. In this case, it is necessary to use two coolers, which increases the cost. Further, in order to cool the two oil passages, it is conceivable to provide a flow path in the area where the two oil passages are merged and install a cooler in the flow path. In this case, since it is necessary to provide a flow path in the AC region, it is necessary to complicate the configuration of the flow path in the oil passage, resulting in high cost.
According to the present embodiment, a cooler is provided only in the first oil passage 91, and the oil O passing through the first oil passage 91 and the second oil passage 92 is mixed in the oil sump P to obtain a second oil passage. The oil passage 92 can be indirectly cooled. As a result, the oil O in the first oil passage 91 and the second oil passage 92 can be cooled by one cooler 97 without complicating the configuration of the flow path in the oil passage 90.
For such an effect, one of the first oil passage 91 and the second oil passage 92 has a cooler 97 for cooling the oil O, and the first oil passage 91 and the second oil have a cooler 97. This is an effect that can be achieved when the oil O flowing through the road 92 merges with the oil sump P.

The heat of the oil O is mainly dissipated through the cooler 97. Further, a part of the heat of the oil O is dissipated through the housing 6 because the oil O comes into contact with the inner surface of the housing 6. As shown in FIG. 1, an uneven heat sink portion 6b may be provided on the outer surface of the housing 6. The heat sink portion 6b promotes cooling of the motor 2 via the housing 6.

(First oil channel)
In the first oil passage 91, the oil O is scooped up from the oil sump P by the differential device 5 and guided to the inside of the rotor 20. Centrifugal force associated with the rotation of the rotor 20 is applied to the oil O inside the rotor 20. As a result, the oil O is evenly diffused toward the stator 30 that surrounds the rotor 20 from the outside in the radial direction to cool the stator 30.

The first oil passage 91 has a scooping path 91a, a shaft supply path (oil flow path) 91b, an in-shaft path 91c, and an in-rotor path 91d. Further, a first reservoir 93 is provided in the path of the first oil passage 91. The first reservoir 93 is provided in the accommodation space 80 (particularly the gear chamber 82).

The scooping path 91a is a path in which the oil O is scooped up from the oil sump P by the rotation of the ring gear 51 of the differential device 5 and the oil O is received in the first reservoir 93 (see FIG. 3).

As shown in FIG. 3, the first reservoir 93 is located above the motor shaft J2, the intermediate shaft J4, and the differential shaft J5 in the vertical direction. The first reservoir 93 is located between the intermediate axis J4 and the differential axis J5 in the vehicle front-rear direction (horizontal direction, X-axis direction). The first reservoir 93 is located between the motor shaft J2 and the differential shaft J5 in the vehicle front-rear direction (horizontal direction, X-axis direction). The first reservoir 93 is arranged on the side of the first gear 41. The first reservoir 93 opens upward.

As used herein, the term "reservoir" means a structure having a function of storing oil in a state where there is no steady flow of liquid in one direction. A "reservoir" differs from a "flow path" in that there is no steady flow of liquid. The accommodation space 80 of the motor unit 1 of the present embodiment is provided with a first reservoir 93, a second reservoir 98, and a sub-reservoir 95.

In the present embodiment, the differential shaft J5, which is the center of rotation of the ring gear 51, is arranged on the rear side of the vehicle with respect to the speed reducing device 4. The differential device 5 rotates upward in a region opposite to the speed reducer 4 when the vehicle moves forward. The oil O scooped up by the ring gear 51 of the differential device 5 goes around the opposite side of the speed reducing device 4 and falls on the upper side of the first reservoir 93 and accumulates in the first reservoir 93. That is, the first reservoir 93 receives the oil O raised by the ring gear 51. Further, when the liquid level of the oil sump P is high, such as immediately after the motor 2 is driven, the second gear 42 and the third gear 43 come into contact with the oil O of the oil sump P and scoop up the oil O. In such a case, the first reservoir 93 receives the oil O scooped up by the second gear 42 and the third gear 43 in addition to the ring gear 51.

The housing 6 has a gear chamber ceiling portion (ceiling portion) 64 that constitutes an upper wall of the gear chamber 82. The gear chamber ceiling portion 64 is located above the speed reducing device 4 and the differential device 5. Here, a virtual line (third line segment described later) L3 that virtually connects the motor shaft J2 and the differential shaft J5 when viewed from the axial direction of the motor shaft J2 is defined. The gear chamber ceiling portion 64 is substantially parallel to the virtual line L3. By making the ceiling portion 64 of the gear chamber substantially parallel to the virtual line L3, a sufficient area for passing the oil O that is scooped up by the ring gear 51 and scattered in the direction in which the virtual line L3 extends is sufficiently secured, and the oil O is supplied. It can be efficiently applied to the first gear 41 that rotates about the motor shaft J. Further, by making the ceiling portion 64 of the gear chamber substantially parallel to the virtual line L3, it is possible to prevent the housing 6 from becoming larger in the vertical direction.
Here, "substantially parallel" between the gear chamber ceiling portion 64 and the virtual line L3 means that the angle formed by the gear chamber ceiling portion 64 and the virtual line L3 is within 10 °. When the ceiling portion 64 of the gear chamber is curved, the angle formed by the tangent line and the virtual line L3 at all points of the curved line is within 10 °.
Further, within the range of 10 ° or less, it is preferable that the gear chamber ceiling portion 64 approaches the virtual line L3 toward the differential shaft J5 side or the motor shaft J2 side. As a result, the housing 6 can be miniaturized.

Further, the gear chamber ceiling portion 64 is a curved surface that is slightly curved in a direction approaching the virtual line L3 side from the differential shaft J5 side toward the motor shaft J2 side. The curved shape of the gear chamber ceiling portion 64 is substantially the same as the parabola drawn by the oil O scooped up by the ring gear 51, or is a curved surface slightly separated from the ring gear 51. A part of the oil O scooped up by the ring gear 51 reaches the first reservoir 93 directly. Further, the other part of the oil O scooped up by the ring gear 51 passes through the gear chamber ceiling portion 64 of the housing 6 and reaches the first reservoir 93. That is, the gear chamber ceiling portion 64 plays a role of inducing the oil O to the first reservoir 93.

The gear chamber ceiling portion 64 has a convex portion 65 projecting downward. The protrusion 65 is located above the first reservoir 93. The oil O propagating through the ceiling portion 64 of the gear chamber becomes a large droplet at the lower end of the convex portion 65, falls downward, and accumulates in the first reservoir 93. That is, the convex portion 65 guides the oil O propagating through the gear chamber ceiling portion 64 to the first reservoir 93.
In the present embodiment, the motor accommodating portion 61 and the gear accommodating portion 62 are fixed to each other by bolts 67. The convex portion 65 is provided in the gear chamber ceiling portion 64 by utilizing a thick portion around a screw hole into which a bolt 67 is inserted. In FIG. 3, other bolts for fixing the motor accommodating portion 61 and the gear accommodating portion 62 and other thick portions around the screw holes are not shown.

The gear chamber ceiling portion 64 has a plate-shaped eaves portion 66 extending along the axial direction. The eaves 66 protrudes downward. The lower end of the eaves 66 is located above the first reservoir 93. A part of the oil O that is scooped up and scattered by the ring gear 51 hits the eaves portion 66 and travels on the surface of the eaves portion 66. Similarly, the oil O that is scooped up and scattered by the second gear 42 and the third gear is received by the eaves portion 66 and travels on the surface of the eaves portion 66. The oil O becomes a large droplet at the lower end of the eaves 66, falls downward, and accumulates in the first reservoir 93. That is, the eaves portion 66 guides the scooped up oil O to the first reservoir 93.
The eaves portion 66 inclines from the differential shaft J5 side toward the motor shaft J2 side from the upper side to the lower side. Since the ring gear 51 has a larger diameter than the second gear 42 and the third gear 43, the scattering angle of the scattered oil O is close to horizontal. By arranging the eaves portion 66 so as to be inclined in the above-mentioned direction, the oil O scattered from the ring gear 51 can be smoothly adhered to the surface of the eaves portion 66 and dropped to the lower side.

The first reservoir 93 is located directly above the ring gear 51, the second gear 42 and the third gear 43. The opening of the first reservoir 93 overlaps with the ring gear 51, the second gear 42, and the third gear 43 when viewed in the vertical direction. Most of the oil pumped up by the gear is scattered directly above the gear being pumped up. By arranging the first reservoir 93 directly above the ring gear 51, the second gear 42, and the third gear 43, the oil O scooped up by each gear can be efficiently received.

The first reservoir 93 has a bottom portion 93a, a first side wall portion 93b, and a second side wall portion 93c. The bottom portion 93a, the first side wall portion 93b, and the second side wall portion 93c extend along the axial direction between the wall surfaces of the gear accommodating portion 62 and the protruding plate portion 61d of the motor accommodating portion. The first side wall portion 93b and the second side wall portion 93c extend upward from the bottom portion 93a. The first side wall portion 93b constitutes the wall surface of the first reservoir 93 on the differential device 5 side. The second side wall portion 93c constitutes the wall surface of the first reservoir 93 on the speed reducing device 4 side. That is, the first side wall portion 93b extends upward from the end portion of the bottom portion 93a on the differential shaft J5 side, and the second side wall portion 93c extends upward from the end portion of the bottom portion 93a on the motor shaft J2 side. The first reservoir 93 is located in a region surrounded by a bottom portion 93a, a first side wall portion 93b, a second side wall portion 93c, and a wall surface of a gear accommodating portion 62 and a protruding plate portion 61d of a motor accommodating portion. , Oil O is temporarily stored.

The height of the upper end portion of the first side wall portion 93b is located below the upper end portion of the second side wall portion 93c. The oil O is scooped up by the differential device 5 and scatters from the opposite side of the speed reducing device 4 toward the first reservoir 93. By lowering the height of the upper end portion of the first side wall portion 93b, the oil O scooped up by the differential device 5 can be efficiently stored in the first reservoir 93. Further, of the oil O that is scooped up and scattered by the ring gear 51, the oil O that exceeds the first side wall portion 93b can be applied to the second side wall portion 93c and guided to the first reservoir 93.

The second side wall portion 93c extends diagonally upward along the circumferential direction of the first gear 41. That is, the second side wall portion 93c inclines toward the motor shaft J2 toward the upper side. As a result, the second side wall portion 93c can receive the oil O scooped up by the differential device 5 in a wide range. In addition, the second side wall portion 93c can receive a wide range of oil O droplets traveling along the ceiling of the accommodation space 80.

A shaft supply flow path 94 opens toward the inside of the first reservoir 93 at the boundary between the bottom portion 93a and the second side wall portion 93c. The bottom portion 93a is slightly inclined downward toward the motor shaft J2 side in a plan view. That is, the bottom portion 93a is slightly inclined so as to be the lower end on the second side wall portion 93c side. Therefore, by providing the opening of the shaft supply flow path 94 between the bottom portion 93a and the second side wall portion 93c, the oil O in the first reservoir 93 can be efficiently supplied to the shaft supply flow path 94.

The shaft supply path 91b guides the oil O from the first reservoir 93 to the motor 2. The shaft supply path 91b is composed of a shaft supply flow path 94. The shaft supply flow path 94 extends from the first reservoir 93 toward the end of the shaft 21. The shaft supply flow path 94 extends linearly. The shaft supply flow path 94 inclines downward from the first reservoir 93 toward the end of the shaft 21. The shaft supply flow path 94 is formed by forming a hole penetrating inside and outside the accommodation space 80 in the gear accommodation portion 62. The outer opening of the machined hole is closed by a cap (not shown). The shaft supply flow path 94 guides the oil O accumulated in the first reservoir 93 from the end portion of the shaft 21 to the hollow portion 22.

As shown in FIG. 1, the in-shaft path 91c is a path through which the oil O passes through the hollow portion 22 of the shaft 21. Further, the rotor inner path 91d is a path that passes through the inside of the end plate 26 located at the axial end surface 24a of the rotor core 24 from the communication hole 23 of the shaft 21 and scatters to the stator 30 (see FIG. 5). That is, the first oil passage 91 has a path from the inside of the shaft 21 to pass through the rotor core 24.

In the in-shaft path 91c, centrifugal force is applied to the oil O inside the rotor 20 as the rotor 20 rotates. As a result, the oil O continuously scatters radially outward from the end plate 26. Further, as the oil O scatters, a negative pressure is generated in the path inside the rotor 20, the oil O accumulated in the first reservoir 93 is sucked into the inside of the rotor 20, and the path inside the rotor 20 is filled with the oil O. .. The oil O is also promoted to move into the rotor 20 by the capillary force in the first oil passage 91. The oil O that has reached the stator 30 takes heat from the stator 30.

(Second oil channel)
As shown in FIG. 1, in the second oil passage 92, the oil O is pulled up from the oil reservoir P to the upper side of the motor 2 and supplied to the motor 2. The oil O supplied to the motor 2 takes heat from the stator 30 while traveling along the outer peripheral surface of the stator 30, and cools the motor 2. The oil O that has traveled along the outer peripheral surface of the stator 30 drops downward and accumulates in the lower region of the motor chamber 81. The oil O in the second oil passage 92 joins the oil O in the first oil passage 91 in the region below the motor chamber 81. The oil O 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 partition wall opening 68.

FIG. 10 is a cross-sectional view of the motor unit 1. The cut surface of FIG. 10 is displaced in the axial direction in each region.
The second oil passage 92 has a first flow path 92a, a second flow path 92b, and a third flow path 92c. A pump 96, a cooler 97, and a second reservoir 98 are provided in the path of the second oil passage 92. In the second oil passage 92, the oil O passes through each part in the order of the first flow path 92a, the pump 96, the second flow path 92b, the cooler 97, the third flow path 92c, and the second reservoir 98. Then, it is supplied to the motor 2.

The pump 96 is an electric pump driven by electricity. The pump 96 is mounted in the pump mounting recess 6c provided on the outer surface of the housing 6. The pump 96 has a suction port 96a and a discharge port 96b. The suction port 96a and the discharge port 96b are connected via an internal flow path of the pump 96. Further, the suction port 96a is connected to the first flow path 92a. The discharge port 96b is connected to the second flow path 92b. The discharge port 96b is located above the suction port 96a. The pump 96 sucks oil O from the oil reservoir P through the first flow path 92a, and the motor 2 passes through the second flow path 92b, the cooler 97, the third flow path 92c, and the second reservoir 98. Supply to.

The amount of oil O supplied to the motor 2 by the pump 96 is appropriately controlled according to the driving state of the motor 2. Therefore, when the temperature of the motor 2 increases, such as when driving for a long time or when a high output is required, the driving output of the pump 96 is increased and the amount of oil O supplied to the motor 2 is increased.

The cooler 97 has an inlet 97a and an outlet 97b. The inflow port 97a and the outflow port 97b are connected via an internal flow path of the cooler 97. Further, the inflow port 97a is connected to the second flow path 92b. The outlet 97b is connected to the third flow path 92c. The inflow port 97a is located closer to (ie, lower) the pump 96 as compared to the outflow port 97b. Further, inside the cooler 97, a cooling water pipe (not shown) through which the cooling water supplied from the radiator passes is provided. The oil O passing through the inside of the cooler 97 is heat-exchanged with the cooling water to be cooled.

The pump 96 and the cooler 97 are fixed to the outer peripheral surface of the motor accommodating portion 61 of the housing 6. The pump 96 and the cooler 97 are located on the opposite sides of the motor shaft J2 in the horizontal direction from the differential device 5 when viewed from the axial direction of the motor shaft J2. Further, the pump 96 and the cooler 97 are arranged in the vertical direction. The cooler 97 is located above the pump 96. The cooler 97 overlaps with the pump 96 when viewed from the vertical direction.

According to the present embodiment, the pump 96 and the cooler 97 are located on opposite sides of the differential device 5 and the motor shaft J2, so that the space around the motor 2 can be effectively used. As a result, it is possible to reduce the size of the entire motor unit 1 along the horizontal direction, and it is possible to reduce the size of the motor unit 1.

According to this embodiment, the pump 96 and the cooler 97 are fixed to the outer peripheral surface of the housing 6. Therefore, the pump 96 and the cooler 97 can contribute to the miniaturization of the motor unit 1 as compared with the case where the pump 96 and the cooler 97 are provided outside the housing 6. In addition, the pump 96 and the cooler 97 are fixed to the outer peripheral surface of the housing 6 so that the first flow path 92a, the second flow path 92b, and the third flow path 92b pass through the inside of the wall portion 6a of the housing 6. The flow path 92c can form a flow path connecting the accommodation space 80 with the pump 96 and the cooler 97.

According to the present embodiment, since the cooler 97 is fixed to the outer peripheral surface of the housing 6, the distance between the accommodation space 80 and the cooler 97 can be shortened. As a result, the third flow path 97c connecting the cooler 97 and the accommodation space 80 can be shortened, and the cooled oil O can be supplied to the accommodation space 80 in a low temperature state.

The first flow path 92a, the second flow path 92b, and the third flow path 92c pass through the inside of the wall portion 6a of the housing 6 surrounding the accommodation space 80. The first flow path 92a can form the first flow path 92a, the second flow path 92b, and the third flow path 92c as holes formed in the wall portion 6a. Therefore, it is not necessary to prepare a separate pipe material, which can contribute to the reduction of the number of parts.
The first flow path 92a passes through the inside of the portion of the wall portion 6a located below the motor 2. The second flow path 92b passes through the inside of the portion of the wall portion 6a located on the horizontal side of the motor 2. Further, the third flow path 92c passes through the inside of the portion of the wall portion 6a located on the upper side of the motor 2.

The first flow path 92a connects the oil reservoir P and the pump 96. The first flow path 92a has a first end portion 92aa and a second end portion 92ab.
The first end 92aa is located upstream of the second oil passage 92 as compared to the second end 92ab. The first end 92aa opens into the accommodation space 80 below the differential device 5. The first end portion 92aa overlaps with the motor 2 when viewed from the vertical direction.
The second end portion 92ab opens in the pump mounting recess 6c and connects to the suction port 96a of the pump 96.

As described above, the differential device 5 and the pump 96 are located on opposite sides of the motor shaft J2 in the horizontal direction. The first flow path 92a extends so as to bridge the motor 2 on the opposite side in the horizontal direction. Further, the first flow path 92a passes under the motor 2.

According to the present embodiment, since the first flow path 92a passes under the motor 2, the dimension of the motor unit 1 can be reduced by effectively utilizing the area under the motor 2. As a result, the size of the motor unit 1 can be reduced.

At least a part of the first flow path 92a is overlapped with the second gear 42 and the ring gear 51 when viewed from the axial direction. As a result, the dimensions of the motor unit 1 when viewed from the axial direction can be reduced, and the size of the motor unit 1 can be reduced.
In this embodiment, of the plurality of gears (first gear 41, second gear 42, third gear 43, and ring gear 51) connected between the motor 2 and the differential device 5, the first gear is used. The case where the gear 42 and the ring gear 51 of No. 2 overlap with the first flow path 92a when viewed from the axial direction has been described. However, if at least one of the plurality of gears connected between the motor 2 and the differential device 5 overlaps with the first flow path 92a when viewed from the axial direction, the above-mentioned effect can be obtained. ..

The first flow path 92a extends from the lower side of the differential device 5 to the suction port 96a of the pump 96. The first flow path 92a is inclined upward and extends linearly from the first end 92aa toward the second end 92ab. Further, the suction port 96a of the pump 96 is located above the lower end of the differential device 5 and below the motor shaft J2.

It is preferable that the pump 96 is arranged at a position away from the road surface in order to prevent a stepping stone from the road surface from colliding with the motor unit 1 mounted on the vehicle. On the other hand, by arranging the suction port 96a of the pump 96 below the oil level of the oil sump P, it is possible to suppress the entrainment of air.

The suction port 96a of the present embodiment is located below the motor shaft J2. As a result, the suction port 96a can be easily arranged below the oil level of the oil sump P. Further, the suction port 96a of the present embodiment is located above the lower end of the differential device 5. This makes it possible to realize a structure in which the pump 96 is separated from the road surface. Further, by arranging the suction port 96a below the motor shaft J2, it becomes easy to form the first flow path 92a in a linear shape. Therefore, when a structure is adopted in which the first flow path 92a passes through the inside of the wall portion 6a of the housing 6, the ease of processing of the first flow path 92a can be improved.

The suction port 96a of the present embodiment is located below the liquid level of the oil sump P in the storage space 80. The height of the liquid level of the oil sump P varies as the oil O is supplied from the oil sump P to the first oil passage 91 and the second oil passage 92. The suction port 96a is located below the liquid level even when the height of the liquid level of the oil sump P is the lowest.
In FIG. 1, the suction port 96a is drawn located above the liquid level of the oil sump P. However, FIG. 1 is only a schematic diagram, and the actual suction port 96a is located below the liquid level of the oil sump P.

The second flow path 92b connects the pump 96 and the cooler 97. The second flow path 92b has a first end portion 92ba and a second end portion 92bb. The first end portion 92ba opens in the pump mounting recess 6c and is connected to the discharge port 96b of the pump 96. The first end portion 92ba is located on the upstream side of the second oil passage 92 as compared with the second end portion 92bb. The second end 92bb connects to the inflow port 97a of the cooler 97. The second end 92bb is located above the first end 92ba.

The second flow path 92b has a first road 92bd and a second road 92be. The first road 92b extends upward from the pump mounting recess 6c. The second road 92be extends horizontally from the upper end of the first road 92bd. The first road 92bd and the second road 92be are formed by processing holes extending from different directions in the wall portion 6a of the housing 6 and intersecting each other.

The third flow path 92c connects the cooler 97 and the accommodation space 80. The third flow path 92c extends linearly along the horizontal direction. The third flow path 92c has a first end 92ca and a second end 92cc. The first end portion 92ca is located on the upstream side of the second oil passage 92 as compared with the second end portion 92cc. The first end portion 92ca is connected to the outlet 97b of the cooler 97. The second end 92cc opens into the accommodation space 80 above the motor 2. That is, the third flow path 92c opens on the upper side of the motor 2 in the accommodation space 80. The second end 92cc of the third flow path 92c functions as a supply unit 99 for supplying the oil O to the second reservoir 98 located in the accommodation space 80. That is, the second oil passage 92 supplies the oil O to the second reservoir 98 in the supply unit 99.

The outlet 97b of the cooler 97 overlaps with the motor 2 in the axial direction of the motor shaft J2. That is, the outlet 97b of the cooler 97 is arranged so as to overlap the motor 2 when viewed from the radial direction. In other words, the outlet 97b of the cooler 97 is located between both ends of the stator 30 in the axial direction. Therefore, the third flow path 92c connecting the outlet 97b of the cooler 97 and the accommodation space 80 can be shortened, and the cooled oil O can be supplied to the accommodation space 80 in a low temperature state. Further, by arranging the third flow path 97c so as to overlap with the motor 2 in the radial direction, the axial dimension of the motor unit 1 can be reduced, and the size of the motor unit 1 can be reduced.

(Second reservoir)
FIG. 11 is a perspective view of the motor unit 1. Further, FIG. 12 is a plan view of the second reservoir 98. In FIG. 11, the motor accommodating portion 61 and the closing portion 63 of the housing 6 are not shown.

As shown in FIG. 11, the second reservoir (main reservoir) 98 is located in the motor chamber 81 of the accommodation space 80. The second reservoir 98 is located above the motor. The second reservoir 98 has a bottom portion (first bottom portion 98c and a second bottom portion 98g) and a side wall portion extending upward from the bottom portion (first side wall portion 98d, second side wall portion 98e, third side wall portion). 98f, a fourth side wall portion 98h, a fifth side wall portion 98i, a sixth side wall portion 98j and a seventh side wall portion 98n). The second reservoir 98 stores the oil O supplied to the motor chamber 81 via the supply portion 99 of the third flow path 92c in a space surrounded by the bottom portion and the side wall portion. The second reservoir 98 has a plurality of outlets (first outlet 98r, second outlet 98o, third outlet 98x, fourth outlet 98t, fifth outlet 98u and sixth outlet 98u). It has an outlet 98v). Each outlet supplies the oil O accumulated in the second reservoir 98 to the motor 2. That is, the second reservoir 98 supplies the oil O stored through the outlet to each part of the motor 2 from above.

According to the present embodiment, the second reservoir 98 is located on the upper side of the motor 2 and supplies the stored oil O to the upper side of the motor 2 from a plurality of outlets. Since the oil O flows from the upper side to the lower side along the outer peripheral surface of the motor 2 and takes heat from the motor 2, the entire motor 2 can be cooled.

As shown in FIG. 12, the second reservoir 98 has a first end 98p located on the gear chamber 82 side in the axial direction and a second end 98p located on the opposite side of the first end 98p in the axial direction. It has an end 98q and. Further, the second reservoir 98 has a gutter-shaped first storage portion 98A extending along the axial direction and a second storage portion located on the second end 98q side with respect to the first storage portion 98A. Has 98B.

The first storage portion 98A has a first bottom portion 98c, a first side wall portion 98d, a second side wall portion 98e, and a third side wall portion 98f. Further, the first storage unit 98A is provided with a first outlet 98r, a second outlet 98o, and a third outlet 98x.

The first bottom portion 98c has a rectangular shape with the axial direction as the longitudinal direction. Both ends of the first bottom portion 98c in the axial direction are located above the coil ends 31a provided at both ends of the stator 30. The first bottom 98c is provided with a first outlet 98r. The first outlet 98r is located in the region on the first end 98p side of the first bottom 98c.

The first side wall portion 98d and the second side wall portion 98e extend along the axial direction. Further, the first side wall portion 98e and the second side wall portion 98e face each other in the circumferential direction of the motor shaft J2.
The inflow port 98s is provided on the first side wall portion 98d. The inflow port 98s is a U-shaped notch that opens upward. A supply unit 99 is connected to the inflow port 98s. The inflow port 98s is located in the middle of the first side wall portion 98d in the axial direction. As a result, the inflow port 98s can flow the oil O to the first end portion 98p and the second end portion 98q side in the second reservoir 98, respectively.

The second side wall portion 98e is provided with a convex portion 98w protruding toward the first side wall portion 98d. The convex portion 98w is located in front of the inflow port 98s. The convex portion 98w has an inclined surface whose protrusion height decreases toward the first end portion 98p side and the second end portion 98q side from the center. The convex portion 98w smoothly divides the oil O flowing from the inflow port 98s to the second reservoir 98 into the first end portion 98p side and the second end portion 98q side.

A second outlet 98o is provided on the second side wall portion 98e. The second outlet 98o is located in the region on the first end 98p side of the second side wall portion 98e. The second outlet 98o is located in the vicinity of the first outlet 98r.

As shown in FIG. 11, the third side wall portion 98f is located on the side of the first end portion 98p of the second reservoir 98. The third side wall portion 98f is located above one coil end 31a of the stator 30. The height of the upper end portion of the third side wall portion 98f is lower than the height of the upper end portion of the first side wall portion 98d and the second side wall portion 98e. Further, the height of the upper end portion of the third side wall portion 98f is substantially equal to the height of the lower end portion of the opening of the second outlet 98o. The space above the second side wall portion 98e functions as a third outlet 98x through which the oil O flows out when the liquid level of the oil O accumulated in the second reservoir 98 becomes high.

The second storage portion 98B extends along the circumferential direction of the stator 30. The second storage portion 98B includes a second bottom portion 98g, a fourth side wall portion 98h, a fifth side wall portion 98i, a sixth side wall portion 98j, a seventh side wall portion 98n, and a step portion 98k. , Have.
Further, the second storage portion 98B is provided with a fourth outlet 98t, a fifth outlet 98u, a sixth outlet 98v, and an overflow portion 98y.

The second bottom 98g is located on the second end 98q side with respect to the first bottom 98c. The second bottom 98g is located below the first bottom 98c. A stepped portion 98k is provided at the boundary between the first bottom portion 98c and the second bottom portion 98g. The second storage unit 98B is located below the first storage unit 98A. The oil O that has flowed to the second end 98q side in the first storage portion 98A is stored in the second storage portion 98B.

The second bottom 98g is located above one coil end 31a of the stator 30. The second bottom portion 98 g is curved along the outer peripheral surface of the motor 2. As a result, the capacity of the oil O stored in the second reservoir 98 can be increased without increasing the size of the motor unit 1. The second bottom portion 98g is inclined downward from the portion overlapping the motor shaft J2 when viewed from the vertical direction toward both sides in the circumferential direction. The second storage unit 98B is connected to the first storage unit 98A on one side of the motor shaft J2 when viewed from the vertical direction.

As shown in FIG. 12, the second storage unit 98B is a region on one side of the motor shaft J2 when viewed from the vertical direction, and the region connected to the first storage unit 98A is the first region 98gA. The region on the other side of the motor shaft J2 is divided into a second region of 98 gB. At the boundary between the first region 98 gA and the second region 98 gB, the second bottom 98 g is the highest. The oil O that has flowed from the first storage portion 98A to the second storage portion 98B first accumulates in the first region 98 gA, and when the liquid level accumulated in the first region 98 gA reaches the height of the boundary line, the oil O Flows into the second region 98 gB. In this way, the boundary line functions as a weir 98gC provided at the second bottom 98g. That is, the second bottom portion 98g is provided with a weir 98gC projecting upward to partition the second storage portion 98B of the second reservoir 98 into the first region 98gA and the second region 98gB. The oil O flows into one region (first region 98 gA), and when the liquid level exceeds the weir 98 gC, it flows into the other region (second region 98 gB).

As will be described later, the sixth side wall portion 98j extending along the circumferential direction is provided with a fourth outlet 98t, a fifth outlet 98u, and a sixth outlet 98v arranged along the circumferential direction. Further, the fifth side wall portion 98i is provided with an overflow portion 98y. The fourth outlet 98t and the fifth outlet 98u open in the first region 98gA, and the sixth outlet 98v and the overflow portion 98y open in the second region 98gB. That is, the second reservoir 98 is provided with outlets in a plurality of regions (first region 98 gA and second region 98 gB) partitioned by the weir 98 gC, respectively. Therefore, the oil O flows out only from the fourth outlet 98t and the fifth outlet 98u until the liquid level of the first region 98gA exceeds the weir 98gC. Further, the oil O flows out from the fourth outlet 98t, the fifth outlet 98u, the sixth outlet 98v, and the overflow portion 98y after the liquid level of the first region 98gA exceeds the weir 98gC. Therefore, according to the present embodiment, the second reservoir 98 can increase the number of outlets to be discharged as the amount of oil O stored increases. In particular, when the load of the motor 2 becomes large and the temperature of the motor 2 becomes high, the supply amount of the oil O supplied to the second reservoir 98 by the pump 96 increases. Therefore, according to the present embodiment, when the motor 2 becomes hot, the supply point of the oil O to the motor 2 is increased to widen the cooling range, and the supply amount of the oil O supplied by the motor 2 is increased. be able to.

The fourth side wall portion 98h and the fifth side wall portion 98i are located at both ends in the circumferential direction of the second storage portion 98B. The fourth side wall portion 98h and the fifth side wall portion 98i face each other in the circumferential direction. The fourth side wall portion 98h and the fifth side wall portion 98i extend along the axial direction. The fourth side wall portion 98h extends continuously to the first side wall portion 98d toward the second end portion 98q.

The fifth side wall portion 98i is provided with an overflow portion 98y. The overflow portion 98y is a portion provided at the upper end of the fifth side wall portion 98i and has a locally low height. The overflow portion 98y is located above the lower end of the openings of the fourth outlet 98t, the fifth outlet 98u, and the sixth outlet 98v of the second storage portion 98B. Therefore, the oil O overflows from the overflow portion 98y after the liquid level in the second reservoir 98B becomes higher than the fourth outlet 98t, the fifth outlet 98u, and the sixth outlet 98v. A sub-reservoir 95, which will be described later, is provided below the overflow portion. The oil O overflowing from the overflow portion 98y is stored in the sub-reservoir 95.
In addition, in this specification, "overflowing" means that when the liquid in a reservoir reaches a certain liquid level, it flows out from the reservoir. Therefore, when the liquid flows out from the bottom of the reservoir, it does not correspond to "overflow".

The sixth side wall portion 98j is located on the second end portion 98q side of the second reservoir 98. The sixth side wall portion 96j extends along the circumferential direction. The sixth side wall portion 98j is located above one coil end 31a of the stator 30. The sixth side wall portion 98j is provided with a fourth outlet 98t, a fifth outlet 98u, and a sixth outlet 98v. The fourth outlet 98t, the fifth outlet 98u, and the sixth outlet 98v are holes provided in the sixth side wall portion 98j and penetrating the inside and outside of the second reservoir 98. The fourth outlet 98t, the fifth outlet 98u, and the sixth outlet 98v are arranged along the circumferential direction. As shown in FIG. 11, the fourth outlet 98t, the fifth outlet 98u, and the sixth outlet 98v have different heights. Therefore, according to the present embodiment, the number of outlets through which the oil O flows out can be increased according to the liquid level of the oil O in the second reservoir 98. As a result, the supply point of the oil O to the motor 2 can be increased to widen the cooling range, and the supply amount of the oil O supplied by the motor 2 can be increased.
It should be noted that such an effect can be achieved if at least two of the plurality of outlets provided in the second reservoir 98 have different heights from each other.

The seventh side wall portion 98n extends along the circumferential direction. The seventh side wall portion 98n faces the sixth side wall portion 98j in the axial direction. The seventh side wall portion 98n is continuous with the step portion 98k along the circumferential direction. The seventh side wall portion 97n is provided with an accommodating portion 98na for accommodating the fixing screw of the stator core 32.

According to the present embodiment, the second oil passage 92 supplies the oil O stored in the second reservoir 98 to the motor 2 from a plurality of outlets. Since each outlet supplies the oil O to the motor 2 at a constant flow rate, the cooling efficiency of the motor 2 by the oil O can be improved.

According to the present embodiment, the second reservoir 98 has a plurality of outlets (first outlet 98r, second outlet 98o, third outlet 98x, fourth outlet 98t, fifth outlet). It has an outlet 98u and a sixth outlet 98v). Therefore, the second reservoir 98 can supply the oil O to the motor 2 from a plurality of places at the same time, and can cool each part of the motor 2 at the same time.

According to this embodiment, the second reservoir 98 extends along the axial direction. Further, the second reservoir 98 is provided with outlets at both ends in the axial direction. Further, the outlets located at both ends in the axial direction of the second reservoir 98 are located above the coil end 31a. As a result, the coil 31 can be directly cooled by applying oil O to the coil ends 31a located at both ends in the axial direction of the stator 30. More specifically, the oil O applied to the coil 31 permeates through the gap between the conducting wires constituting the coil 31. The oil O that has soaked into the coil 31 takes heat from the coil while penetrating the entire coil 31 by the capillary force and gravity acting on the conduit. Further, the oil O collects at the lowermost portion of the inner peripheral surface of the stator core 32 and drips from both ends in the axial direction of the coil 31.
The effect of directly cooling the oil O by directly supplying the oil O to the coil end 31a is that at least two of the plurality of outlets are in the axial direction of the second reservoir 98. It is an effect that can be achieved by being located at both ends.

According to the present embodiment, the supply unit 99 for supplying the oil O to the second reservoir 98 is located between the outlets located at both ends of the second reservoir 98 in the axial direction. Therefore, the oil O supplied from the supply unit 99 can flow out the oil O from the outlets located at both ends.

(Modification example of the second reservoir)
FIG. 13 is a perspective view of a second reservoir 198 of a modification that can be adopted in this embodiment. The components having the same embodiment as those described above will be described with reference to the same reference numerals.
The second reservoir 198 of the modified example is a rectangular shallow box shape with an opening on the upper side. The second reservoir 198 has a central oil storage unit 198a and four oil supply units 198b located around the central oil storage unit 198a. The central oil storage section 198a and the four oil supply sections 198b are separated from each other.

The central oil storage unit 198a stores the oil O flowing in from the supply unit 99. The central oil storage portion 198a is separated from the oil supply portion 198b by a circular bottom surface 198ab and a cylindrical wall 198aa extending upward from the bottom surface 198ab.

The four oil supply units 198b are arranged so as to surround the central oil storage unit 198a. The oil supply unit 198b has a substantially rectangular shape. An outflow port 198c that communicates with the inside and outside of the oil supply unit 198b is provided in the vicinity of the corners of the two outer walls 198ba extending in different directions of the oil supply unit 198b. One of the two outlets 198c opens in the axial direction of the motor 2, and the other opens in the circumferential direction. Since each of the four oil supply units 198b has two outlets 198c, the second reservoir 198 has a total of eight outlets 198c.

The second reservoir 198 is installed above the stator 30 so that the bottom surface is horizontal. When the oil O supplied from the supply unit 99 fills the central oil storage unit 198a, it overflows from the cylindrical wall 198aa and flows into the four oil supply units 198b. Since the second reservoir 198 is installed horizontally and the cylindrical wall 198aa has the same height on the entire circumference, the oil O flows evenly into the four oil supply portions 198b. The oil O accumulates in the four oil supply units 198b and flows out from the outlet 198c to the outside.

The axial length of the second reservoir 198 is longer than the axial length of the stator core 32. The oil O is supplied from one oil supply unit 198b to the motor 2 via two outlets 198c facing in the axial direction and the circumferential direction. According to this modification, the second reservoir 198 can supply oil O to the motor 2 from a plurality of outlets in a plurality of directions.

(Secondary reservoir)
FIG. 14 is a cross-sectional view of the motor unit 1 showing an outline of the sub-reservoir 95. In FIG. 14, the protruding portion 63d provided in the closed portion 63 of the housing 6 is shown by a virtual line. Further, in FIG. 14, the oil O stored in the sub-reservoir 95 is highlighted by a dot pattern.
The sub-reservoir 95 receives the oil O overflowing from the second reservoir 98 in the second oil passage 92. That is, an auxiliary reservoir 95 for storing the oil O is provided in the path of the second oil passage 92. The second reservoir 98 functions as a main reservoir with respect to the sub-reservoir 95. The second reservoir 98 is located upstream of the second oil passage 92 with respect to the secondary reservoir 95.

The sub-reservoir 95 is located directly below the overflow portion 98y. That is, the sub-reservoir 95 and the overflow portion 98y overlap each other when viewed from the vertical direction. As a result, the oil O overflowing from the second reservoir 98 can be received by the sub-reservoir 95.

The sub-reservoir 95 has a first portion 95A located on one side in the circumferential direction with respect to the second reservoir 98 and a second portion 95B located on the other side in the circumferential direction. The first portion 95A and the second portion 95B are connected to each other. The sub-reservoir 95 has a total of four outlets 61k, two each in the first portion 95A and the second portion 95B. The four outlets 61k are arranged along the circumferential direction of the motor 2. Further, the heights of the plurality of outlets 61k are different from each other.

The sub-reservoir 95 is composed of an inner wall surface of an inner side surface 61 g of the motor accommodating portion 61 and an inner wall surface of the protruding portion 63d of the closed portion 63. The inner side surface 61g of the motor accommodating portion 61 has an inner peripheral surface 61i facing inward in the radial direction and a facing surface 61h facing the closed portion 63 side in the axial direction. The facing surface 61h comes into contact with the axially facing surface of the protrusion 63d. Oil O does not flow out from the contact portion between the protruding portion 63d and the facing surface 61h. According to the present embodiment, since the sub-reservoir 95 is configured as a gap between other members, it is not necessary to use other members, and an increase in the number of parts can be suppressed.

The facing surface 61h is provided with recesses 61j that are aligned along the circumferential direction and recessed in the axial direction. The recess 61j is recessed in a direction that increases the gap between the inner surface 61g of the motor accommodating portion 61 and the inner wall surface of the protrusion 63d. The oil O flows downward from the recess 61j. That is, the recess 61j constitutes the outlet 61k. The outlet 61k is located above the coil end 31a of the stator 30. Therefore, the oil O flowing out from the outlet 61k cools the coil 31 of the coil end 31a.
In this embodiment, a case where the concave portion 61j is provided on the inner side surface 61g at the contact portion between the inner side surface 61g of the motor accommodating portion 61 and the inner wall surface of the protruding portion 63d is exemplified. However, a recess may be provided on the inner wall surface of the protruding portion 63d.

According to the present embodiment, by providing the sub-reservoir 95 in addition to the second reservoir 98, the oil O flows out from the outlet 61k of the sub-reservoir 95 in addition to the outlet of the second reservoir 98. And can cool a wide range of the motor 2. Further, a plurality of outlets 61k of the sub-reservoir 95 are arranged side by side along the circumferential direction. As a result, the coil end 31a of the stator 30 can be cooled in a wide range. Further, since the heights of the plurality of outlets 61k are different from each other, the timing of outflow can be different depending on the liquid level of the oil O accumulated in the sub-reservoir 95.

According to the present embodiment, the oil O overflowing from the second reservoir 98 is stored in the sub-reservoir 95. The pump 96 increases the supply amount of oil O supplied to the second reservoir 98 when the motor 2 becomes a high load and the temperature rises. Therefore, when the motor 2 has a high load, the oil O overflows from the second reservoir 98, and the oil O can be supplied to the motor 2 even at the outlet 61k of the sub-reservoir 95. According to this embodiment, when the motor 2 has a high load, a wide range of the motor 2 can be cooled by the oil O. That is, by providing the sub-reservoir 95, the supply range of the oil O supplied to the motor 2 can be automatically expanded when the operation of the motor 2 changes from the steady state to the high load state.

Further, the lower end of the sub-reservoir 95 of the present embodiment is located above the motor shaft J2. Therefore, the outlet 61k of the sub-reservoir 95 is located above the motor shaft J2. The motor 2 has a substantially cylindrical shape. By setting the lower end of the sub-reservoir 95 above the motor shaft J2, the oil O flowing out from the outlet 61k can be transmitted along the surface of the motor 2 to cool the motor 2. Further, the motor 2 has the widest width in the horizontal cross section passing through the motor shaft J2. By locating the lower end of the sub-reservoir 95 above the motor shaft J2, the oil O traveling on the surface of the motor 2 passes through the region having the widest horizontal dimension of the motor. As a result, the motor 2 can be efficiently cooled.

(Intersection of the first oil passage and the second oil passage)
As shown in FIG. 1, in the driving state of the motor 2, the oil O is supplied to the motor 2 via the first oil passage 91 and the second oil passage 92. The oil O supplied to the motor 2 is dropped on the lower side while cooling the motor 2, and is accumulated in the lower region of the motor chamber 81. The oil O accumulated in the lower region of the motor chamber 81 moves to the gear chamber 82 through the partition wall opening 68 provided in the partition wall 61c.

FIG. 15 is a front view of the partition wall 61c of the housing 6 as viewed from the motor chamber 81 side.
The partition wall opening 68 is located below the insertion hole 61f through which the shaft 21 is inserted. The partition wall opening 68 has a first opening 68a and a second opening 68b located above the first opening 68a. The first opening 68a and the second opening 68b communicate the motor chamber 81 and the gear chamber 82, respectively.

As shown in FIG. 19, the lower end of the partition wall opening 68 (that is, the lower end of the first opening 68a) is located above the lower limit height Lmin of the oil O of the gear chamber 82 in the stationary state of the motor 2. do. Therefore, the partition wall opening 68 can move as much oil O as possible to the oil sump P in a stopped state in which the driving of the motor 2 is stopped.

As shown in FIG. 15, the first opening 68a is circular in a plan view. The lower end of the first opening 68a is located below the lower end of the stator 30. The first opening 68a is located in the vicinity of the bottom 81a of the motor chamber 81. Therefore, the first opening 68a moves the oil O to the gear chamber 82 until the oil O accumulated in the lower region of the motor chamber 81 is substantially exhausted.

The first opening 68a overlaps with the motor shaft J2 when viewed from the vertical direction. Further, the first opening 68a is located in the recess 61q provided on the inner peripheral surface of the peripheral wall portion 61a. Here, the peripheral wall portion 61a and the recess 61q will be described. The motor accommodating portion 61 of the housing 6 has a peripheral wall portion 61a having a cylindrical shape along the outer peripheral surface of the stator 30. A recess 61q recessed outward in the radial direction is provided on the inner peripheral surface of the peripheral wall portion 61a. The recess 61q extends along the axial direction. The recess 61q is located directly below the motor shaft J2. That is, the recess 61q overlaps with the motor shaft J2 when viewed from the vertical direction. Since the peripheral wall portion 61a has a cylindrical shape, the oil O in the motor chamber 81 travels along the inner peripheral surface of the peripheral wall portion 61a and collects inside the recess 61q. Since the first opening 68a is located in the recess 61q, the oil O in the motor chamber 81 collected inside the recess 61q can be efficiently moved to the gear chamber 82.

The second opening 68b is located above the first opening 68a. The second opening 68b is a rectangle whose longitudinal direction is the horizontal direction in a plan view. The second opening 68b has a larger opening area than the first opening 68a. Further, the second opening 68b has a larger width along the horizontal direction than the first opening 68a. The second opening 68b has a lower end 68c extending along the horizontal direction.

By driving the motor 2, the amount of oil O supplied to the motor 2 from the oil passage 90 (that is, the first oil passage 91 and the second oil passage 92) increases per unit time. As a result, the liquid level of the oil O accumulated in the lower region of the motor chamber 81 rises. In the partition wall opening 68, the region located below the liquid level of the oil O accumulated in the region below the motor chamber 81 is referred to as the first region S, and the region located above the liquid level is referred to as the second region R. Called. The partition wall opening 68 moves the oil O to the gear chamber 82 in the first region S. When the liquid level of the oil O accumulated in the lower region of the gear chamber 82 rises, the area of the first region S becomes large and the area of the second region R becomes small. When the area of the first region S becomes large, the amount of oil O transferred from the motor chamber 81 to the gear chamber 82 through the partition wall opening 68 increases.

The partition wall opening 68 of the present embodiment is arranged so that when the liquid level of the oil O in the motor chamber 81 becomes high, the amount of oil O moving from the motor chamber 81 to the gear chamber 82 via the partition wall opening 68 increases. Will be done. Therefore, it is suppressed that the liquid level of the oil O in the motor chamber 81 becomes too high. That is, it is possible to prevent the rotor 20 in the motor chamber 81 from being immersed in the oil O or excessively scooping up the oil O. Therefore, it is possible to prevent the rotational efficiency of the motor 2 from decreasing due to the flow resistance of the oil O.
In addition, according to the present embodiment, the oil O in the motor chamber 81 is moved to the gear chamber 82 side according to the height of the liquid level of the oil O in the motor chamber 81, so that the oil in the motor unit 1 is used. O can be effectively used. As a result, not only the amount of oil O used can be suppressed and the weight of the motor unit 1 can be reduced, but also the energy efficiency required for cooling the oil O can be improved.

As shown in FIG. 19, the lower end of the second opening 68b is the height of the liquid level of the oil O in the gear chamber 82 (upper limit height Lmin and lower limit height Lmin) regardless of whether the motor 2 is stationary or driven. Located on the upper side. Therefore, the second opening 68b does not submerge on the gear chamber 82 side. The second opening 68b can move the oil O to the gear chamber 82 regardless of the liquid level of the gear chamber 82, and can prevent the rotor 20 from being immersed in the oil O.

A change in the amount of movement of the oil O moving through the partition wall opening 68 with the rise of the liquid level of the oil O accumulated on the lower side of the motor chamber 81 will be described more specifically. Here, the liquid level of the oil O that collects on the lower side of the motor chamber 81 and reaches the lower end 68c of the second opening 68b is defined as the first liquid level OL. That is, the lower end of the second opening 68b is located at the first liquid level OL. The first liquid level OL is located above the lower end of the stator 30 and below the lower end of the rotor 20.

FIG. 16 is a graph showing the relationship between the height of the liquid level of the oil O accumulated under the motor chamber 81 and the area of the first region S. The area of the first region S has a correlation (substantially proportional relationship) with the flow rate of the oil O flowing out from the partition wall opening 68.

The oil O is supplied to the motor 2 together with the drive of the motor 2, and begins to accumulate in the lower region of the motor chamber 81. The oil O accumulated in the lower region of the motor chamber 81 moves from the motor chamber 81 to the gear chamber 82 via the first opening 68a. When the supply amount of oil O per unit time supplied to the motor 2 exceeds the flow rate of the oil O moving from the motor chamber 81 to the gear chamber 82 through the first opening 68a, the lower side of the motor chamber 81 The liquid level of oil O accumulated in the region of No. rises. When the liquid level reaches the first liquid level OL, the oil O flows out from the second opening 68b in addition to the first opening 68a. Since the second opening 68b has a larger width along the horizontal direction than the first opening 68a, the area of the first region S rapidly increases before and after the liquid level reaches the first liquid level OL. do. Along with this, the flow rate of the oil O flowing from the motor chamber 81 to the gear chamber 82 through the partition wall opening 68 rapidly increases. As described above, the first liquid level OL is set below the lower end of the rotor 20. Therefore, according to the present embodiment, it is possible to prevent the rotational efficiency of the rotor 20 in the motor chamber 81 from decreasing due to the flow resistance of the oil O.

The horizontal width of the second opening 68b is such that the flow rate of the oil O flowing out of the partition wall opening 68 when the liquid level reaches above the first liquid level OL is supplied to the motor 2 in the oil passage 90. It is preferable that the width is larger than that of the oil O. As a result, it is possible to prevent the liquid level of the oil O accumulated in the lower region of the motor chamber 81 from significantly exceeding the first liquid level OL, and to prevent the rotor 20 from being immersed in the oil O.

As shown in FIG. 1, the first oil passage 91 includes a pumping path 91a and an in-rotor path 91d. The hoisting path 91a moves the oil O from the gear chamber 82 to the motor chamber 81 by hoisting the oil) by the differential device 5. The amount of oil O scooped up by the differential device 5 depends on the rotation speed of the differential device 5. Therefore, the scooping path 91a increases or decreases the amount of oil O moving to the motor chamber 81 depending on the vehicle speed. Further, the rotor inner path 91d sucks the oil O from the gear chamber 82 side to the motor chamber 81 side by the centrifugal force of the rotor 20. Centrifugal force depends on the rotation speed of the rotor 20. Therefore, the rotor path 91d increases or decreases the amount of oil O moving to the motor chamber 81 depending on the vehicle speed. That is, in the first oil passage 91, the amount of oil O moving to the motor chamber 81 increases or decreases depending on the vehicle speed.

On the other hand, in the second oil passage 92, the oil O is moved from the gear chamber 82 to the motor chamber 81 by the pump (electric pump) 96. The amount of oil O supplied to the pump 96 is controlled, for example, based on the temperature measurement result of the motor 2. Therefore, in the second oil passage 92, the amount of oil O moving to the motor chamber 81 increases or decreases regardless of the vehicle speed.

The second oil passage 92 stops the supply of oil O to the motor 2 when the motor 2 is stationary. Further, the second oil passage 92 starts the movement of the oil O to the motor chamber 81 when the motor 2 is started. Therefore, when stopped, the liquid level of the oil sump P in the gear chamber 82 can be raised. As a result, the rotation of the motor 2 immediately after the start causes the second gear 42, the third gear 43, and the ring gear 51 to rotate in the oil reservoir P, so that the oil O can be distributed to the tooth surface.

According to the present embodiment, the second oil passage 92 pulls the oil O from the oil sump P regardless of the speed of the vehicle. Therefore, the second oil passage 92 can lower the height of the oil level of the oil sump P even when the vehicle travels at a low speed. As a result, it is possible to prevent the rotational efficiency of the gear in the gear chamber 82 from being lowered by the oil O in the oil sump P during low-speed traveling.

(Modified example of partition wall opening)
FIG. 17 is a front view of the partition wall opening 168 of the modified example that can be adopted in the present embodiment. The components having the same embodiment as those described above will be described with reference to the same reference numerals.
The partition wall opening 168 of the modified example has a long hole portion 168a extending in the vertical direction and a wide expansion portion 168b connected to the long hole portion 168a on the upper side of the long hole portion 168a. The lower end of the elongated hole portion 168a is located in the vicinity of the bottom portion 81a of the motor chamber 81. The elongated hole portion 168a overlaps with the motor shaft J2 when viewed from the vertical direction. The expansion portion 168b is wide in the horizontal direction with respect to the elongated hole portion 168a. The extension portion 168b is a rectangle whose longitudinal direction is the horizontal direction in a plan view. The extension 168b has a lower end 168c that extends horizontally. The lower end 168c is located at the above-mentioned first liquid level OL.
In the partition wall opening 168, the region located below the liquid level of the oil O is referred to as a first region S, and the region located above the liquid level is referred to as a second region R.

FIG. 18 is a graph showing the relationship between the height of the liquid level of the oil O accumulated under the motor chamber 81 and the area of the first region S in this modification.
When the liquid level reaches the first liquid level OL in this modification, the oil O flows out from the expansion portion 168b in addition to the elongated hole portion 168a, and the area of the first region S rapidly increases. Along with this, the flow rate of the oil O flowing from the motor chamber 81 to the gear chamber 82 through the partition wall opening 168 rapidly increases. Since the first liquid level OL is set below the lower end of the rotor 20, it is possible to prevent the rotational efficiency of the rotor 20 from decreasing due to the flow resistance of the oil O.

(Liquid level height of oil pool)
As shown in FIG. 1, in the first oil passage 91, the pump 96 is driven in the driving state of the motor 2 to supply oil O from the oil reservoir P to the motor 2. Further, in the first oil passage 91, in the driving state of the motor 2, the oil O is moved from the oil reservoir P to the first reservoir 93 by scooping up the differential device 5, and the oil O is supplied to the inside of the motor 2. do. That is, both the first oil passage 91 and the second oil passage 92 supply the oil O from the oil reservoir P to the motor 2 in the driving state of the motor 2. Therefore, in the driving state of the motor 2, the liquid level of the oil sump P located in the lower region of the gear chamber 82 is lowered. Further, since the oil O supplied to the motor 2 accumulates in the space below the motor chamber 81, the liquid level of the oil O accumulated in the region below the motor chamber 81 rises in the driving state of the motor 2. ..

On the other hand, in the stopped state of the motor 2, the first oil passage 91 and the second oil passage 92 stop the supply of oil O to the motor 2. As a result, the oil O dropped below the motor 2 once accumulates in the lower region of the motor chamber 81, and moves to the oil reservoir P in the lower region of the gear chamber 82 via the partition wall opening 68. Therefore, in the stopped state of the motor 2, the liquid level of the oil O accumulated in the lower region of the motor chamber is lowered, and the liquid level of the oil pool P located in the lower region of the gear chamber 82 is raised.

FIG. 19 is a side view showing the arrangement of each gear located inside the gear chamber 82. In FIG. 19, the gear accommodating portion 62 of the housing 6 and the bearings that support each shaft are omitted.
As shown in FIG. 19, according to the present embodiment, the height of the liquid level of the oil O accumulated in the oil reservoir P is such that the oil O is in the oil passage 90 (the first oil passage 91 and the second oil passage 92). It fluctuates between the upper limit height Lmax and the lower limit height Lmin. As shown in FIG. 1, a first reservoir 93 is provided in the first oil passage 91. Further, the second oil passage 92 is provided with a second reservoir 98 and a sub-reservoir 95 (omitted in FIG. 1, see FIG. 14). Further, oil O is collected in the lower region of the motor chamber 81 where the first oil passage 91 and the second oil passage 92 meet. In this way, several places where the oil O is collected are provided in the paths of the first oil passage 91 and the second oil passage 92. As a result, by supplying the oil O to the motor 2, the oil O accumulated in the oil reservoir P moves to the reservoir or the like in the above-mentioned path, and the liquid level of the oil reservoir P drops. As a result, the gear in the gear chamber 82 can be exposed from the oil O in the oil sump P, and the rotation efficiency of the gear can be improved.

As shown in FIG. 19, among a pair of gears (second gear 42 and third gear 43) rotating around the intermediate shaft J4, the lower end of the second gear 42 having a large diameter and connected to the motor 2. Is located below the upper limit height Lmax of the liquid level. Further, the lower end of the second gear 42 is located above the lower limit height Lmin of the liquid level.
Similarly, of the pair of gears (second gear 42 and third gear 43) that rotate about the intermediate shaft J4, the lower end of the third gear 43, which has a smaller diameter and is connected to the differential device 5, is liquid. It is located below the upper limit height Lmax of the surface. Further, the lower end of the third gear 43 is located above the lower limit height Lmin of the liquid level.

The liquid level of the oil sump P reaches the upper limit height Lmax when the motor 2 is stopped and the supply of oil O from the oil sump P to the motor 2 is stopped. According to the present embodiment, in the stopped state of the motor 2, a part of the second gear 42 and the third gear 43 can be in a state of being immersed in the oil O of the oil sump P. As a result, when the motor 2 is driven, the oil O can be immediately distributed to the tooth surfaces of the second gear 42 and the third gear 43, and the transmission efficiency between the gears can be improved.

The liquid level of the oil sump P reaches the lower limit height Lmin in a state where the motor 2 is driven with a high load and the supply of oil O from the oil sump P to the motor 2 is most promoted. According to the present embodiment, since the second gear 42 and the third gear 43 are located above the liquid level of the oil sump P in the driving state of the motor 2, the second gear 42 is caused by the flow resistance of the oil O. It is possible to suppress a decrease in rotational efficiency of the gear 42 and the third gear 43. Thereby, the driving efficiency of the motor unit 1 can be improved.

The lower end of the ring gear 51 provided in the differential device 5 and connected to the speed reducing device 4 and rotating about the differential shaft J5 is located below the liquid surface at the upper limit height Lmax and the lower limit height Lmin of the liquid level. ..
According to the present embodiment, at least a part of the ring gear 51 is located below the liquid level of the oil O of the oil sump P regardless of the fluctuation of the liquid level of the oil sump P. Therefore, even when the motor 2 is driven and the liquid level of the oil sump P becomes low, the ring gear 51 can scoop up the oil O from the oil sump P, and the oil O can be pumped from each gear in the gear chamber 82. Oil O can be supplied to the tooth surface of the wheel to increase the torque transmission efficiency between the gears.

(Summary of oil channels)
With reference to FIG. 1, the flow of oil O in the oil passage 90 accompanying the driving of the motor unit 1 will be described.
When the motor unit 1 is mounted on a hybrid vehicle or a plug-in hybrid vehicle, it is one of an engine mode driven only by an engine, a motor mode driven only by a motor 2, and a hybrid mode driven by both an engine and a motor. Drive in one mode.

In the engine mode, the motor 2 is stopped, but the differential device 5 is driven by the engine, so that the oil O is scooped up from the oil sump P. The oil O that has been scooped up accumulates in the first reservoir 93, but is not scattered toward the stator 30 because the rotor 20 does not rotate. Further, in the engine mode, the pump 96 is not driven and the oil O is not supplied to the second oil passage 92.

In the motor mode and the hybrid mode, when the vehicle climbs a slope, the output of the motor 2 increases and the amount of heat generated by the motor 2 increases. In such a case, the discharge amount of the pump 96 is increased to supply more oil O to the stator 30, thereby accelerating the cooling. On the other hand, when the vehicle goes down a slope (that is, when the motor 2 is not loaded), or when the motor 2 does not reach a high temperature state such as when the vehicle is started or used in a cold region, the pump is used. The discharge rate of 96 is reduced.

The second oil passage 92 can adjust the supply amount to the motor 2 by the pump 96 according to the temperature of the motor 2, the drive mode of the vehicle, and the like. According to this embodiment, the energy required for cooling the motor 2 can be made efficient. Such an effect can be achieved when the pump 96 is an electrically driven pump.
The discharge amount of the pump 96 can be managed based on the temperature data detected by the temperature sensor provided in the motor 2. Further, the temperature change of the motor 2 can be predicted by combining each data such as the operation history of the vehicle, the driving state, the posture of the vehicle, the outside air temperature, the weight of the occupant and the luggage. Based on the predicted value of this temperature change, the motor 2 may be managed so as not to be in a high temperature state.

According to the present embodiment, since the oil passage 90 supplies the oil O to the stator 30 from a plurality of places, the entire stator 30 can be efficiently cooled. Further, according to the present embodiment, the oil O functions as a cooling oil and a lubricating oil. Therefore, it is not necessary to separately provide a path for the cooling oil and a path for the lubricating oil, and the cost can be reduced.

(Countermeasures against contamination in oil channels)
The oil O used for cooling the motor unit 1 is used for lubricating the differential device 5 and the speed reducer 4. Therefore, there is a possibility that contamination such as metal powder generated by mechanical contact may be mixed in the oil O. Contamination may deteriorate the fluidity of oil O in the first oil passage 91 and the second oil passage 92. Contamination is removed by regular replacement of oil O. Further, one or both of the first oil passage 91 and the second oil passage 92 may be provided with means for capturing contamination. As an example, as shown in FIG. 9, a permanent magnet 98 m may be installed in the second reservoir 98 to magnetically capture the contamination and suppress the diffusion of the contamination. In this case, deterioration of the fluidity of the oil O can be suppressed.

(Arrangement of each axis)
The motor shaft J2, the intermediate shaft J4, and the differential shaft J5 extend parallel to each other along the horizontal direction. The intermediate shaft J4 and the differential shaft J5 are located below the motor shaft J2. Therefore, the speed reducer 4 and the differential device 5 are located below the motor 2.

When viewed from the axial direction of the motor shaft J2, the line segment that virtually connects the motor shaft J2 and the intermediate shaft J4 is defined as the first line segment L1, and the line segment that virtually connects the intermediate shaft J4 and the differential shaft J5. Is a second line segment L2, and a line segment that virtually connects the motor shaft J2 and the differential shaft J5 is a third line segment L3.

According to the present embodiment, the second line segment L2 extends along a substantially horizontal direction. That is, the intermediate axis J4 and the differential axis J5 are aligned substantially in the horizontal direction. Therefore, the speed reducing device 4 and the differential device 5 can be arranged along the horizontal direction, and the vertical dimension of the motor unit 1 can be reduced. Further, the oil O scooped up by the differential device 5 can be efficiently applied to the speed reducing device 4. As a result, oil O can be supplied to the tooth surface of the gear constituting the reduction gear 4 to improve the transmission efficiency of the gear. The diameter of the gears (second gear 42 and third gear 43) that rotate around the intermediate shaft J4 is smaller than the diameter of the ring gear 51 that rotates about the differential shaft J5. According to the present embodiment, since the second line segment L2 extends along the substantially horizontal direction, the intermediate axis J4 and the differential axis J5 are arranged along the substantially horizontal direction. Therefore, depending on the height of the liquid level of the oil sump P, only the ring gear 51 is immersed in the oil sump P, and the second gear 42 and the third gear 43 are not immersed in the oil sump P. Therefore, it is possible to suppress a decrease in the rotational efficiency of the second gear 42 and the third gear 43 while the ring gear 51 scoops up the oil O in the oil sump P.
In the present embodiment, the second line segment L2 is in a substantially horizontal direction within ± 10 ° with respect to the horizontal direction.

According to the present embodiment, the angle α formed by the second line segment L2 and the third line segment L3 is 30 ° ± 5 °. As a result, the transmission efficiency of the oil O pumped up by the differential device 5 between the first gear 41 and the second gear 42 can be improved, and a desired gear ratio can be realized.
When the angle α exceeds 35 °, it becomes difficult to supply the oil scooped up by the differential device to the gear (first gear) that rotates around the motor shaft. This may reduce the transmission efficiency between the first gear and the second gear. On the other hand, if the angle α is less than 25 °, the gear on the output side in the transmission process cannot be made sufficiently large, and the desired gear ratio is achieved in the three axes (motor shaft, intermediate shaft and differential shaft). Will be difficult.

According to the present embodiment, the first line segment L1 extends substantially in the vertical direction. That is, the motor shaft J2 and the intermediate shaft J4 are aligned substantially along the vertical direction. Therefore, the motor 2 and the speed reducer 4 can be arranged along the vertical direction, and the horizontal dimension of the motor unit 1 can be reduced. Further, by setting the first line segment L1 in the substantially vertical direction, the motor shaft J2 can be arranged close to the differential shaft J5, and the first gear 41 rotating about the motor shaft J2 can be placed on the first gear 41. The oil O scooped up by the differential device 5 can be supplied. Thereby, the transmission efficiency between the first gear 41 and the second gear 42 can be improved.
In the present embodiment, the direction in which the first line segment L1 is substantially vertical is a direction within ± 10 ° with respect to the vertical direction.

The length L1 of the first line segment, the length L2 of the second line segment, and the length L3 of the third line segment satisfy the following relationship.
L1: L2: L3 = 1: 1.4 to 1.7: 1.8 to 2.0
Further, the reduction ratio in the reduction mechanism from the motor 2 to the differential device 5 is 8 or more and 11 or less.
According to this embodiment, a desired gear ratio (8 or more and 11 or less) can be realized while maintaining the positional relationship between the motor shaft J2, the intermediate shaft J4, and the differential shaft J5 as described above.

<Parking mechanism>
FIG. 20 is a diagram showing a parking mechanism 7 that can be adopted in the motor unit 1 of the present embodiment.
The parking mechanism 7 is effective when the motor unit 1 is used in an electric vehicle (EV).
In a manual transmission vehicle driven by an engine, in addition to operating the side brake, by setting the transmission to a position other than neutral, it is possible to apply a load to the engine and bring about the braking action. In an automatic transmission vehicle, in addition to operating the side brake, the transmission can be locked by setting the shift lever to the parking position.
On the other hand, in an electric vehicle, since there is no braking mechanism for braking the vehicle other than the side brake, the motor unit 1 requires a parking mechanism 7.

The parking mechanism 7 includes a ring-shaped parking gear 71, a parking pole 72, a parking rod 73, and a parking lever 74. The parking gear 71 is arranged coaxially with the second gear (intermediate gear) 42 and the third gear 43 and the intermediate gear. The parking gear 71 is fixed to the intermediate shaft 45. The parking pole 72 has a protrusion 72a that bites into the groove of the parking gear 71 to prevent the parking gear 71 from rotating. The parking rod 73 is connected to the parking pole 72 and moves the protrusion 72a along the radial direction of the parking gear. The parking lever 74 is connected to the parking rod 73 and drives the parking rod 73.

When the motor 2 is operating, the parking pole 72 is retracted from the parking gear 71. On the other hand, when the shift lever is in the parking position, the parking pole 72 bites into the parking gear 71 and prevents the parking gear 71 from rotating.

The parking pole 72 is controlled by a parking motor (not shown) connected to the parking lever. Since the parking mechanism 7 can be electrified by using the parking motor, the components for driving the parking mechanism 7 can be simplified. Further, when the parking motor is used, the parking pole 72 can be driven by a push button, a paddle lever, or the like, so that the operability of the driver is improved. Such a mechanism is called a shift-by-wire system.
The parking mechanism 7 may be a manual type instead of an electric type using a shift-by-wire system. That is, the driver may drive the parking pole by mechanically pulling the wire connected to the parking lever.

According to this embodiment, the parking mechanism 7 is provided on the intermediate shaft 45. As a result, in the torque transmission process from the motor 2 to the axle 55, the braking torque for preventing the rotation of the parking gear 71 can be reduced as compared with the case where the parking mechanism 7 is provided in the gear behind the intermediate shaft. As a result, the structure of the parking mechanism can be made smaller and lighter. Further, when the parking mechanism 7 is electric, a small parking motor can be adopted. Further, when the parking mechanism is a manual type, the burden on the driver's operation can be reduced.

Further, according to the present embodiment, the parking mechanism 7 is located below the speed reducing device 4. Therefore, the parking pole 72 is in a state of being immersed in the oil O of the oil sump P, and the oil O is interposed between the parking gear 71 and the protrusion 72a of the parking pole 72 to smoothly attach and detach the protrusion 72a. be able to.
The parking mechanism 7 of the present embodiment is an example, and other conventionally known structures may be adopted. Further, the parking mechanism 7 may be arranged so as to apply a braking force to the shaft 21 or the ring gear 51 connected to the motor 2.

<Modification 1>
<Detachment mechanism>
FIG. 21 is a partial cross-sectional view showing the disconnection mechanism 107 of the motor unit 101 of the modified example 1.
As a modification 1, the motor unit 101 of the modification provided with the disconnection mechanism 107 in the torque transmission path from the motor 2 to the axle 55 will be described. The motor unit 101 of this modification is mainly different in that a disconnection mechanism 107 is provided on the shaft 121 of the motor 2. The components having the same embodiment as those described above will be described with reference to the same reference numerals.

The disconnection mechanism 107 is provided when the motor unit 101 is mounted on a hybrid electric vehicle (HEV) and a plug-in hybrid vehicle (PHV). The hybrid vehicle and the plug-in hybrid vehicle travel in any one of an engine mode driven only by the engine, a motor mode driven only by the motor 2, and a hybrid mode driven by both the engine and the motor. The disconnection mechanism 107 axles the power transmission mechanism (rotor 20, speed reducer 4, differential device 5 of the motor 2) of the motor unit 101 so that the stopped motor 2 does not become a load in an automobile traveling in the engine mode. Separate from 55.

As shown in FIG. 21, in this modification, the shaft 121 is a coaxially arranged first shaft portion 121A, a connecting shaft portion 121C and a second shaft portion 121B, and a connecting shaft portion 121C and a second shaft portion 121B. It has a disconnection mechanism 107 located between them. The first shaft portion 121A, the connecting shaft portion 121C, and the second shaft portion 121B are arranged in this order along the axial direction. That is, the connecting shaft portion 121C is located between the first shaft portion 121A and the second shaft portion 121B.

The shaft 121 is a hollow shaft provided with a hollow portion 122 having an inner peripheral surface extending along the motor shaft J2 inside. The hollow portion 122 includes a first hollow portion 122A located inside the first shaft portion 121A, a second hollow portion 122B located inside the second shaft portion 121B, and a third hollow portion 122 located inside the connecting shaft portion 121C. The hollow portion 122C and the like are included. The first hollow portion 122A, the second hollow portion 122B, and the third hollow portion 122C are arranged along the axial direction and communicate with each other.

The first shaft portion 121A is arranged in the motor chamber 81 of the accommodation space 80. The first shaft portion 121A is located inside the stator 30 in the radial direction and penetrates the rotor core 24 along the motor shaft J2.
The first shaft portion 121A has a first end portion 121e located on the output side (that is, the speed reducing device 4 side).

The first end portion 121e passes through the insertion hole 61f provided in the partition wall 61c from the motor chamber 81 side. The first hollow portion (second concave portion) 122A opens on the surface of the first end portion 121e facing the axial direction. The first end portion 121e is rotatably supported by a first bearing 89 held in contact with the surface of the partition wall 61c facing the motor chamber 81 side.
By holding the first bearing 89 in contact with the surface of the partition wall 61c facing the motor chamber 81 side, the axis alignment of the first shaft portion 121A can be performed at the portion of the housing 6 on the motor chamber 81 side. As a result, the alignment of the first shaft portion 121A with respect to the stator 30 can be performed with high accuracy.

The connection shaft portion 121C is arranged inside the insertion hole 61f. The connection shaft portion 121C is rotatably supported by a second bearing 188A which is held in contact with the surface of the partition wall 61c facing the gear chamber 82 side. The second bearing 188A is a ball bearing. The connecting shaft portion 121C is provided with a stepped surface 121q facing the partition wall 61c side. The step surface 121q comes into contact with the inner ring of the second bearing 188A.

According to this modification, the second bearing 188A is held on the surface of the partition wall 61c facing the gear chamber 82 side. Therefore, the connecting shaft portion 121C can be assembled to the first shaft portion 121A after the axis alignment of the first shaft portion 121A is performed. Therefore, the assembly process of the connection shaft portion 121C can be simplified.

The outer diameter of the second bearing 188A is larger than the outer diameter of the first bearing 89. When the disconnection mechanism 107 is operated, a large load is applied to the second bearing 188A in the axial direction and the circumferential direction. According to the second bearing 188A of this modification, by making the diameter larger than that of the first bearing 89, it is possible to secure sufficient strength against the load during operation of the disconnection mechanism 107. ..

The connection shaft portion 121C has a second end portion 121f, a third end portion 121g, and a connection flange portion 121h.

The second end portion 121f projects toward the motor chamber 81 side. The second end portion 121f is located on the side of the first shaft portion 121A and is connected to the first end portion 121e of the first shaft portion 121A. The second end portion 121f is housed in a first hollow portion 122A that opens into the first end portion 121e. The outer peripheral surface of the second end portion 121f is fitted to the inner peripheral surface of the first hollow portion 122A. By fitting the second end portion 121f into the first hollow portion 122A, the connecting portion between the first end portion 121e and the second end portion 121f can be miniaturized in the radial direction. As a result, it is possible to secure a space for arranging the first bearing 89 on the radial outer side of the first end portion 121e.

The third end portion 121g projects toward the gear chamber 82 side. The third end portion 121g is located on the opposite side of the second end portion 121f and on the side of the second shaft portion 121B. A first recess 121p is provided at an axially oriented end of the third end 121g.
The connection flange portion 121h extends radially outward of the third end portion 121g. The diameter of the connection flange portion 121h is larger than the smallest diameter portion of the insertion hole 61f.

According to this modification, the connecting shaft portion 121C is a separate member from the first shaft portion 121A. Therefore, by assembling the connecting shaft portion 121C to the first shaft portion 121A after the assembly step of the motor 2, the assembly can be performed in the same order as the assembly order when the disconnection mechanism 107 is not provided. Along with this, the shape of the parts other than the shaft 121 can be the same as when there is no disconnection mechanism 107. That is, according to this modification, it is possible to standardize the parts between the motor unit 101 having the disconnection mechanism 107 and the motor unit 1 not having the disconnection mechanism 107. Further, since the assembly order can be the same regardless of the presence or absence of the disconnection mechanism 107, it is possible to suppress the complexity of the component shape and the increase in the number of components. Therefore, according to this modification, it is possible to provide a highly versatile and low-cost motor unit 101.

The second shaft portion 121B is arranged in the gear chamber 82 of the accommodation space 80.
The second shaft portion 121B has a fourth end portion 121i and a fifth end portion 121j.

The fourth end portion 121i is located on the third end portion 121g side of the connection shaft portion 121C. Power transmission is selectively disconnected from the fourth end portion 121i and the connection flange portion 121h of the connection shaft portion 121C by the disconnection mechanism 107.

The fourth end 121i is housed in a first recess 121p provided in the third end 121g. Needle bearings (bearings) 121n are provided in the radial gaps between the third end portion 121g and the fourth end portion 121i. That is, according to this modification, the second shaft portion 121B is rotatably supported by the connecting shaft portion 121C at the fourth end portion 121i. Therefore, according to this modification, when the second shaft portion 121B and the connecting shaft portion 121C are separated by the disconnection mechanism 107, stable holding can be realized without hindering the relative rotation. It should be noted that such an effect can be achieved when one of the third end portion 121g and the fourth end portion 121i is provided with a first recess for accommodating the other via the needle bearing 121n. be.

In this modification, the needle bearing 121n is formed by arranging a plurality of columnar members in an annular shape, but the needle bearing 121n may be replaced with another bearing mechanism such as a ball bearing. However, by adopting the needle bearing, the radial dimensions of the third end portion 121g and the fourth end portion 121i can be reduced, and the motor unit 101 can be downsized.

As described above, the first shaft portion 121A, the connecting shaft portion 121C, and the second shaft portion 121B are each provided with a hollow portion 122 extending in the axial direction and communicating with each other. Similar to the above-described embodiment, the hollow portion 122 is supplied with oil O for cooling the inside of the motor from the second shaft portion 121B side toward the first shaft portion 121A side.
According to this modification, the connecting shaft portion 121C and the second shaft portion 121B are connected via the needle bearing 121n. Therefore, the third hollow portion 122C of the connecting shaft portion 121C and the second hollow portion 122B of the second shaft portion 121B can be connected to each other. As a result, the oil O can be supplied to the hollow portion 122 and used as an oil flow path.

The fifth end 121j is located on the opposite side of the fourth end 121i. The fifth end is rotatably supported by a third bearing 188B held in the housing. That is, the second shaft portion 121B is supported by the third bearing 188B at the fifth end portion 121j.
According to this modification, the second shaft portion 121B is supported by two bearings (needle bearing 121n and third bearing 188B) arranged in the axial direction. Similarly, the connecting shaft portion 121C is supported by two bearings (second bearing 188A and needle bearing 121n) arranged in the axial direction. The second shaft portion 121B and the connecting shaft portion 121C are rotatably supported at two points arranged in the axial direction, so that the second shaft portion 121B and the connecting shaft portion 121C can rotate stably without causing shaft shake.

A first gear 41 is provided on the outer peripheral surface of the second shaft portion 121B. The first gear 41 is located between the fourth end 121i and the fifth end 121j. The first gear 41 transmits power to the second gear 42 of the speed reducer 4. According to this modification, the first gear 41 is located between the second bearing 188A and the third bearing 188B. Therefore, the first gear 41 can rotate stably with respect to the motor shaft J2, and the torque generated by the motor 2 can be stably transmitted to the second gear 42.

The disconnection mechanism 107 surrounds the connection flange portion 121h of the connection shaft portion 121C and the fourth end portion 121i of the second shaft portion 121B from the outside in the radial direction. The disconnection mechanism 107 uses the drive unit 175 to switch between a state in which the connection flange portion 121h and the fourth end portion 121i are not mechanically connected and a state in which both are connected.

The disconnection mechanism 107 is located between the axial end surface of the motor 2 and the first gear 41 in the axial direction. The motor unit 101 adopts a three-axis structure of a motor shaft J2, an intermediate shaft J4, and a differential shaft J5. Further, in the axial direction, a third gear 43 is located between the axial end surface of the motor 2 and the first gear 41. The second gear 42 rotates synchronously with the second gear 42 connected to the first gear 41. A gap larger than the thickness of the third gear 43 is provided between the axial end surface of the motor 2 and the first gear 41. According to this modification, the disconnection mechanism 107 is arranged between the axial end surface of the motor 2 and the first gear 41. That is, the third gear 43 and the disconnection mechanism 107 are arranged at positions where they overlap in the axial direction. As a result, the internal space of the gear chamber 82 can be effectively used to reduce the size of the motor unit 101.

According to this modification, the disconnection mechanism is provided on the shaft 121 of the motor 2. That is, in the power transmission path from the motor 2 to the axle 55, the disconnection mechanism 107 is provided at the portion having the smallest torque. According to this modification, since the torque transmitted through the disconnection mechanism 107 is small, the disconnection mechanism can be miniaturized.

The disconnection mechanism 107 of this modification is referred to as a rotation synchronization device or a synchromesh mechanism. In this modification, the disconnection mechanism 107 is an example. As the disconnection mechanism, for example, a dog clutch mechanism or a multi-stage clutch mechanism may be adopted.

The disconnection mechanism 107 includes a sleeve 171, a clutch hub 172, a synchronizer ring 173, a key 174, and a drive unit (not shown).

The clutch hub 172 is fixed to the outer peripheral surface of the second shaft portion 121B. The clutch hub 172 rotates about the motor shaft J2 together with the second shaft portion 121B. An external tooth spline is provided on the outer periphery of the clutch hub 172.

The sleeve 171 is movable along the axial direction. The sleeve 171 meshes with the external tooth spline of the clutch hub 172 and rotates integrally with the sleeve 171. Further, a spline is provided on the inner peripheral surface of the sleeve 171. The spline of the sleeve 171 fits into the spline provided on the outer peripheral surface of the connecting flange portion 121h after the clutch hub 172 and the connecting flange portion 121h rotate synchronously. As a result, the second shaft portion 121B and the connecting shaft portion 121C are connected.

The key 174 is held by the sleeve 171. The key 174 moves axially with the sleeve 171. The key 174 matches the phases of the splines provided on the sleeve 171 and the connection flange portion 121h, respectively.

The synchronizer ring 173 moves in the axial direction together with the sleeve 171. The synchronizer ring 173 has a tapered surface whose inner diameter increases as it approaches the connection flange portion 121h side. On the other hand, the connection flange portion 121h is provided with a boss portion that protrudes toward the synchronizer ring 173 along the axial direction. The boss portion is provided with a tapered surface facing the synchronizer ring 173. The synchronizer ring 173 and the connecting flange portion 121h rotate synchronously by bringing the tapered surfaces into contact with each other.

The drive unit (not shown) is connected to the sleeve 171. The drive unit moves the sleeve 171 in the axial direction.

FIG. 22 is a conceptual diagram showing a state in which the motor 2 and the speed reducing device 4 are connected by the disconnection mechanism 107, and FIG. 23 is a concept showing a state in which the motor 2 and the speed reducing device 4 are separated by the disconnection mechanism 107. It is a figure.
As described above, the motor unit 101 provided with the disconnection mechanism 107 is mounted on a hybrid vehicle or a plug-in hybrid vehicle. In such a vehicle, when the mode of traveling using only the power of the engine and the mode of traveling using the power of the motor 2 are switched, the drive unit 175 operates and the connection shaft portion 121C and the second shaft portion 121B are operated. You can switch between connecting and disconnecting with.

The control regarding the disconnection mechanism 107 will be described. When the disconnection mechanism 107 switches from the disconnected state to the connected state, first, the rotation speed of the second shaft portion 121B is calculated from the rotation speed of the axle 55. Next, the rotation speed of the motor 2 is increased to the calculated rotation speed of the second shaft portion 121B. While the rotation speed of the motor 2 is increasing, the sleeve is moved by the drive unit 175, and the connection between the second shaft portion 121B and the connection shaft portion 121C is realized. After that, the position where the connection between the second shaft portion 121B and the connection shaft portion 121C is completed is calculated from the cumulative rotation speed of the drive unit 175. Finally, it is detected that the rotation speed of the motor 2 and the rotation speed of the second shaft portion 121B calculated from the rotation speed of the axle 55 are the same, and it is finally determined that the joining state is completed. Will be done.

<Control>
Each element such as the motor 2 of the motor unit 1, the pump 96, the drive unit 175 of the disconnection mechanism 107, and the parking motor of the parking mechanism 7 is centrally controlled by the micro control unit (MCU). The micro control unit may be provided integrally with the motor unit 1 or may be provided externally.

<Mounting on a vehicle>
The motor unit 1 can be applied to any of a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHV), and an electric vehicle (EV). Further, the motor unit 1 can be applied not only to passenger cars but also to freight vehicles (trucks) and the like. The motor unit 1 may be mounted on either the front side or the rear side of the vehicle, but it is preferably mounted on the rear side. Since the motor unit 1 of the present embodiment has a small vertical dimension, it can be compactly installed even on the rear side where the installation space is limited due to the restrictions of the luggage compartment and the minimum ground clearance.

Although the embodiments and modifications of the present invention have been described above, the configurations and combinations thereof in the embodiments are examples, and the configurations are added, omitted, replaced, and the like without departing from the spirit of the present invention. Other changes are possible. Further, the present invention is not limited to the embodiments.

1,101 ... Motor unit (electric drive device), 2 ... Motor, 4 ... Reducer, 5 ... Differential device, 6 ... Housing, 6a ... Wall, 20 ... Rotor, 21,121 ... Shaft, 21A, 121A ... 1st shaft part, 21B, 121B ... 2nd shaft part, 21c ... bearing part, 21c ... bearing part (lid part), 21d ... screw part, 21e, 121e ... first end part, 21f, 121f ... second end part , 21g, 121g ... 3rd end, 21h, 121i ... 4th end, 22,122 ... Hollow part, 22A, 122A ... 1st hollow part, 22q ... 2nd region (small diameter hollow part), 22r ... 3rd Region (large diameter hollow portion), 22t ... 2nd stepped surface (stepped surface), 22u ... concave groove, 23 ... communication hole, 24 ... rotor core, 24a ... axial end surface, 24b ... outer peripheral surface, 24d ... magnet holding hole, 24e ... Core through hole, 25 ... Rotor magnet, 26,126,226 ... End plate, 26a, 126a, 226a ... First surface, 26b, 126b, 226b ... Second surface, 26e, 126u ... Inclined surface, 26f , 61j, 61q ... concave groove, 26j, 126j, 226j ... first concave groove (first concave groove), 26k, 126k, 226k, 226kA, 226kB ... second concave groove (second concave groove), 26p, 126p , 226p ... Plate through hole, 26r ... Second opening (opening), 26s ... First opening (opening), 26t ... Oil flow path, 28 ... Washer (lid), 29 ... Nut, 30 ... Stator, 31 ... Coil, 31a ... Coil end, 32 ... Stator core, 41 ... First gear, 42 ... Second gear (intermediate gear), 43 ... Third gear, 51 ... Ring gear, 61 ... Motor housing , 61c ... partition wall, 61f ... insertion hole, 61k, 97b, 98r, 98o, 98x, 98t, 98u, 98v, 198c ... outlet, 63 ... closed part, 63d ... protruding part, 64 ... gear chamber ceiling part (ceiling part) ), 65 ... convex portion, 66 ... eaves portion, 68,168 ... partition wall opening, 68a ... first opening, 68b ... second opening, 80 ... accommodation space, 81 ... motor chamber, 82 ... gear chamber, 88, 188A ... 2nd bearing, 89 ... 1st bearing, 90 ... oil passage, 91 ... first oil passage (oil passage), 91a ... scooping path, 91b ... shaft supply path (oil flow path), 92 ... second oil passage (oil passage), 92a ... first flow path, 92b ... second flow path, 92c, 92aa, 92ba, 92ca ... first end, 92ab, 92bb, 92cc ... second. End, 97c ... 3rd flow path, 93 ... 1st reservoir (reservoir) ), 95 ... Sub-reservoir, 96 ... Pump (electric pump), 96a ... Suction port, 97 ... Cooler, 98, 198 ... Second reservoir (main reservoir), 98y ... Overflow part, 99 ... Supply part, 107 ... Detachment Mechanism, 121C ... Connection shaft part, 121h ... Connection flange part, 121j ... Fifth end part, 121n ... Needle bearing (bearing), 121p ... First concave part, 121q ... Step surface, 126r, 226r ... Open part, 128,228 ... lid, 168a ... long hole, 168b ... expansion, 98gC ... dam, J2 ... motor shaft, J4 ... intermediate shaft, J5 ... differential shaft, L1 ... first line segment, L2 ... second line segment , L3 ... 3rd line segment (virtual line), Lmax ... upper limit height, Lmin ... lower limit height, O ... oil, OL ... first liquid level, P ... oil pool, S ... first region

Claims (8)

A rotor that rotates around the motor shaft and
The rotor is provided with a stator located on the outer side in the radial direction.
The rotor is
A shaft extending along the motor shaft and
A rotor core that surrounds the shaft from the outside in the radial direction,
A lid located at the axial end of the rotor core and
A plate-shaped end plate located between the rotor core and the lid,
Have,
The stator has a coil end that projects axially from the end of the rotor core.
The shaft has an inner peripheral surface extending in the axial direction and a hollow portion to which oil is supplied to the inside, and a communication hole extending in the radial direction to communicate the hollow portion and the outside of the shaft. Provided,
The end plate has a first surface facing the axial end surface of the rotor core and a second surface facing the opposite side of the first surface.
The end plate has a plate through hole extending in the axial direction, a first recess located on the first surface and extending radially inward from the plate through hole, and a plate through hole located on the second surface. A groove-shaped second recess extending radially outward from the hole is provided.
The first recess opens radially inside the end plate and connects to the communication hole.
The axially oriented opening of the first recess is covered by the rotor core and
The axially oriented opening of the second recess has a covering portion covered by the lid portion and an open portion not covered by the lid portion.
The open portion is located at the radial outer end of the second recess.
The axially oriented opening of the plate through hole is covered by the lid.
motor. The bottom of the second recess is provided with an inclined surface in which the depth of the second recess becomes shallower toward the outside in the radial direction.
The motor according to claim 1 . The rotor has a pair of the end plates and a pair of the lids.
The end plate and the lid are arranged on one side and the other side in the axial direction of the rotor core, respectively.
The shaft is provided with a pair of communication holes connected to the first recesses of the pair of end plates.
The motor according to any one of claims 1 or 2 . The rotor core is provided with a core through hole that penetrates along the axial direction.
The core through hole connects the first recesses of each of the pair of end plates to each other.
At least a part of the opening of the core through hole is located radially outside the plate through hole.
The motor according to claim 3 . On the outer peripheral surface of the shaft, a flange portion and a screw portion arranged along the axial direction are provided.
The rotor core and the pair of end plates are sandwiched between the flange portion and a nut fastened to the screw portion.
A washer is interposed between the nut and the end plate,
One of the pair of lids is the collar.
The other of the pair of lids is the washer,
The motor according to claim 3 or 4 . The radial outer end of the second recess is a groove extending along the radial direction.
The direction in which the groove extends when viewed from the axial direction is inclined with respect to the radial direction.
The motor according to any one of claims 1 to 5 . The end plate is provided with a plurality of the second recesses.
The radial outer end of the second recess is a groove extending along the radial direction.
The extending direction of the groove of each of the plurality of second recesses when viewed from the axial direction has a different angle with respect to the radial direction.
The motor according to any one of claims 1 to 5 . The first surface is provided with an inclined surface that inclines toward the rotor core side toward the outside in the radial direction.
The inclined surface extends along the circumferential direction outside the first recess and comes into contact with the axial end surface of the rotor core.
The motor according to any one of claims 1 to 5 .

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