WO2019098166A1

WO2019098166A1 - Motor unit

Info

Publication number: WO2019098166A1
Application number: PCT/JP2018/041917
Authority: WO
Inventors: 山口　康夫; 勇樹石川; 慶介福永
Original assignee: 日本電産株式会社
Priority date: 2017-11-14
Filing date: 2018-11-13
Publication date: 2019-05-23
Also published as: CN111295535B; CN117028539A; CN111295535A

Abstract

This motor unit is provided with: a motor having a shaft that rotates about a motor axis; a speed reduction device being connected to the shaft and having an intermediate gear that rotates about an intermediate axis; a differential device being connected to the speed reduction device and having a ring gear that rotates about a differential axis; a housing that is provided with a gear chamber for accommodating the speed reduction device and the differential device; and oil that is pooled in the gear chamber. The motor axis, the intermediate axis, and the differential axis extend in parallel with each other in the horizontal direction. The intermediate axis and the differential axis are located below the motor axis. The ring gear is at least partially soaked in the oil that is pooled in the lower area of the gear chamber. The housing has a first oil receiving part that is located below the intermediate gear and that extends along the tooth top circle of the intermediate gear. In the first oil receiving part, oil scooped up from the lower area in the gear chamber by rotation of the ring gear is pooled. The oil pooled in the first oil receiving part is scooped up by the intermediate gear.

Description

Motor unit

The present invention relates to a motor unit.

Patent Document 1 describes a structure in which oil accumulated in the bottom of a case is scraped up by the rotation of a gear.

Japanese Published Gazette: Japanese Patent Laid-Open No. 2014-20450

The motor unit preferably picks up the oil and distributes the oil to the gears regardless of the direction of rotation of the motor. With such a configuration of the motor unit, oil can be distributed to the gears not only when the vehicle moves forward but also when the vehicle moves backward. Further, since there is no restriction on the rotational direction of the motor when moving the vehicle forward, the degree of freedom of the arrangement of the motor unit with respect to the vehicle can be increased, and the common motor unit can be mounted on various vehicles. On the other hand, there are various restrictions on the arrangement of each gear in the motor unit from the viewpoint of safety and gear ratio setting. Therefore, in the conventional motor unit, when the motor rotates in the reverse direction, the oil can not be distributed to the gears by the scraping by the gears.

SUMMARY OF THE INVENTION In view of the above-described problems, one aspect of the present invention aims to provide a motor unit capable of scraping oil in a gear chamber regardless of the rotation direction of an axle and distributing the oil to each gear.

One aspect of the motor unit according to the present invention includes a motor having a shaft rotating about a motor shaft, a reduction gear having an intermediate gear connected to the shaft and rotating about an intermediate shaft, and the reduction gear A differential gear having a ring gear that rotates about a differential shaft, a housing provided with the reduction gear and a gear chamber for accommodating the differential gear, and oil accumulated in a lower region of the gear chamber. The motor shaft, the intermediate shaft and the differential shaft extend in parallel in the horizontal direction. The intermediate shaft and the differential shaft are located below the motor shaft. At least a portion of the ring gear is immersed in the oil collected in the lower region of the gear chamber. The housing has a first oil receiver located below the intermediate gear and extending along a tip circle of the intermediate gear. The oil scooped up from the lower region of the gear chamber by the rotation of the ring gear is accumulated in the first oil receiving portion. The oil accumulated in the first oil receiving portion is scooped up by the intermediate gear.

According to one aspect of the present invention, there is provided, for example, a motor unit capable of scraping oil in a gear chamber regardless of the rotational direction of an axle.

FIG. 1 is a conceptual view of a motor unit according to the first embodiment. FIG. 2 is a side view of the motor unit of the first embodiment. FIG. 3 is a conceptual view showing a part of a motor unit of a modification. FIG. 4 is a side view of the motor unit of the second embodiment. FIG. 5 is a cross-sectional view of the motor unit taken along the line VV of FIG.

Hereinafter, a motor according to an 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. Moreover, in the following drawings, in order to make each structure intelligible, a scale, the number, etc. in an actual structure and each structure may be varied.

In the following description, the direction of gravity is defined and described based on the positional relationship when the motor unit 1 is mounted on a vehicle located on a horizontal road surface. In the drawings, an XYZ coordinate system is shown as a three-dimensional orthogonal coordinate system as appropriate. In the XYZ coordinate system, the Z-axis direction indicates the vertical direction (that is, the vertical direction), the + Z direction is the upper side (opposite the gravity direction), and the -Z direction is the lower side (gravity direction). 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 vehicle front, and the −X direction is the vehicle rear. 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 noted in the following description, the direction (Z-axis direction) parallel to the motor axis J2 of the motor 2 is simply referred to as “axial direction”, and the radial direction centered on the motor axis J2 is simply referred to as “radial direction”. The circumferential direction around the motor axis J2, that is, around the axis of the motor axis J2, is simply referred to as "circumferential direction". Furthermore, in the following description, “plan view” means a state viewed from the axial direction. However, the above-mentioned "parallel direction" also includes a substantially parallel direction. Further, the above-mentioned "orthogonal direction" also includes a substantially orthogonal direction.

First Embodiment
Hereinafter, a motor unit (electric drive apparatus) 1 according to an exemplary first embodiment of the present invention will be described based on the drawings. FIG. 1 is a conceptual view of a motor unit 1 according to an embodiment. FIG. 2 is a side view of the motor unit 1.

The motor unit 1 is mounted on a vehicle having a motor as a power source such as a hybrid vehicle (HEV), a plug-in hybrid vehicle (PHV), an electric vehicle (EV), and used as the power source.

As shown in FIG. 1, the motor unit 1 includes a motor (main motor) 2, a reduction gear 4, a differential device 5, a housing 6 and an oil O. An interior of the housing 6 is provided with a housing space 80 for housing the motor 2, the reduction gear 4 and the differential gear 5. The housing space 80 is divided into a motor chamber 81 housing the motor 2 and a gear chamber 82 housing the reduction gear 4 and the differential gear 5.

<Motor>
The motor 2 is accommodated in a motor chamber 81 of the housing 6. The motor 2 includes a rotor 20 and a stator 30 located radially outward of the rotor 20. The motor 2 is an inner rotor type motor including a stator 30 and a rotor 20 rotatably disposed inside the stator 30.

The rotor 20 rotates by supplying power to the stator 30 from a battery (not shown). The rotor 20 has a shaft (motor shaft) 21, a rotor core 24, and a rotor magnet (not shown). That is, the motor 2 has a shaft 21, a rotor core 24, and a rotor magnet. The rotor 20 rotates about a motor axis J2 extending in the horizontal direction. The torque of the rotor 20 is transmitted to the differential 5 via the reduction gear 4.

The shaft 21 extends around a motor axis J2 extending in the horizontal direction and the width direction of the vehicle. The shaft 21 rotates about the motor axis J2. The shaft 21 is a hollow shaft provided with a hollow portion 22 having an inner circumferential surface extending along the motor axis J2.

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

The rotor core 24 is configured by laminating silicon steel plates. The rotor core 24 is a cylindrical body extending along the axial direction. A plurality of rotor magnets (not shown) are fixed to the rotor core 24. The plurality of rotor magnets are arranged along the circumferential direction with the magnetic poles alternately.

The stator 30 surrounds the rotor 20 from the radially outer side. The stator 30 has a stator core 32, a coil 31, and an insulator (not shown) interposed between the stator core 32 and the coil 31. The stator 30 is held by the housing 6. The stator core 32 has a plurality of magnetic pole teeth (not shown) radially inward from the inner circumferential surface of the annular yoke. A coil wire is wound around the pole teeth. The coil wire wound around the pole teeth constitutes a coil 31. The coil 31 has a coil end 31 a protruding from the axial end surface of the stator core 32. The coil end 31 a protrudes in the axial direction more than the end of the rotor core 24 of the rotor 20. The coil end 31 a protrudes on both sides in the axial direction with respect to the rotor core 24.

<Reduction gear>
The reduction gear 4 has a function of reducing the rotational speed of the motor 2 and increasing the torque output from the motor 2 according to the reduction ratio. The reduction gear 4 is connected to the shaft 21 of the motor 2. The reduction gear 4 transmits the torque output from the motor 2 to the differential 5.

The reduction gear 4 has a pinion gear 41, an intermediate shaft 45, and a pair of

intermediate gears

42 and 43 fixed to the intermediate shaft 45. The torque output from the motor 2 is transmitted to the ring gear 51 of the differential 5 through the shaft 21 of the motor 2, the pinion gear 41, and the pair of

intermediate gears

42 and 43. The gear ratio of each gear, the number of gears, etc. can be variously changed according to the required reduction ratio. The reduction gear 4 is a reduction gear of a parallel axis gear type in which axes of the respective gears are arranged in parallel.

The pinion gear 41 is fixed to the outer peripheral surface of the shaft 21 of the motor 2. The pinion gear 41 rotates around the motor shaft J2 together with the shaft 21.

The intermediate shaft 45 extends along an intermediate axis J4 parallel to the motor axis J2. The middle shaft 45 rotates around the middle axis J4.

The intermediate gears 42 and 43 have a large diameter gear (intermediate gear) 42 and a small diameter gear (intermediate gear) 43 aligned in the axial direction. The large diameter gear 42 and the small diameter gear 43 are provided on the outer peripheral surface of the intermediate shaft 45. The large diameter gear 42 and the small diameter gear 43 are connected via an intermediate shaft 45. The large diameter gear 42 and the small diameter gear 43 rotate about the intermediate shaft J4. At least two of the large diameter gear 42, the small diameter gear 43 and the intermediate shaft 45 may be composed of a single member. The large diameter gear 42 meshes with the pinion gear 41. The small diameter gear 43 meshes with the ring gear 51 of the differential device 5.

<Differential device>
The differential device 5 is connected to the motor 2 via the reduction gear 4. The differential 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 the left and right wheels while absorbing the speed difference between the left and right wheels when the vehicle is turning.

The differential 5 has a ring gear 51, a gear housing (not shown), 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 axis J5 parallel to the motor axis J2. The torque output from the motor 2 is transmitted to the ring gear 51 via the reduction gear 4.

<Housing>
The housing 6 holds the motor 2, the reduction gear 4 and the differential 5 in the housing space 80. The housing 6 has a partition wall 61c. The partition wall 61 c divides the housing space 80 of the housing 6 into a motor chamber 81 and a gear chamber 82. That is, the motor chamber 81 and the gear chamber 82 are provided in the housing 6. The motor 2 is accommodated in the motor chamber 81. In the gear chamber 82, the reduction gear 4 and the differential 5 are accommodated.

The partition wall 61c is provided with a shaft passage hole 61f and a partition opening 68. The shaft passage hole 61 f and the partition opening 68 communicate the motor chamber 81 with the gear chamber 82. The shaft 21 passes through the shaft passage hole 61 f. The partition opening 68 is located below the shaft passage hole 61 f. The partition wall opening 68 is provided in the vicinity of the bottom 81 a of the motor chamber 81. The bottom 81 a of the motor chamber 81 is located above the bottom 82 a of the gear chamber 82. Therefore, the oil O which has cooled the motor 2 moves from the motor chamber 81 to the gear chamber 82 through the partition opening 68.

In the lower region of the gear chamber 82, an oil reservoir P in which the oil O is accumulated is provided. In the following description, the lower region in the gear chamber 82 is referred to as an oil reservoir P. A part of the differential device 5 is immersed in the oil reservoir P. That is, at least a part of the ring gear 51 is immersed in the oil O accumulated in the oil reservoir P.

The oil O accumulated in the oil reservoir P is scooped up by the operation of the reduction gear 4 and the differential device 5 and a part is supplied to the first oil passage 91 and a part is diffused in the gear chamber 82. The oil O diffused to the gear chamber 82 is supplied to the gears of the reduction gear 4 and the differential gear 5 in the gear chamber 82 and spreads the oil O on the tooth surfaces of the gears. The oil O supplied to the reduction gear 4 and the differential device 5 and used for lubrication is dropped and collected in an oil reservoir P located below the gear chamber 82. The capacity of the oil O in the housing space 80 is set to such an extent that a part of the bearing of the differential 5 is immersed in the oil O when the motor unit 1 is stopped.

The housing 6 has a first oil receiving portion 69, a second oil receiving portion 93, and an oil introduction passage 94. The first oil receiving portion 69, the second oil receiving portion 93, and the oil introduction path 94 are disposed in the gear chamber 82 of the gear housing portion 62. The first oil receptacle 69 and the second oil receptacle 93 open upward. The first oil receiving portion 69 and the second oil receiving portion 93 function as a reservoir for temporarily storing oil. The oil introduction path 94 connects the second oil receiving portion 93 and the inside of the shaft 21.

As shown in FIG. 2, the first oil receiving portion 69 is located below the

intermediate gears

42, 43. The first oil receiving portion 69 extends along the tip circle of the

intermediate gears

42, 43. More specifically, the first oil receiving portion 69 is located below the large diameter gear 42 of the pair of intermediate gears 42 and 73 and extends along the tip circle of the large diameter gear 42. The oil O picked up by the differential device 5 is accumulated in the first oil receiving portion 69.

The oil O accumulated in the first oil receiving portion 69 is scooped up by the rotation of the large diameter gear 42. Since the first oil receiving portion 69 extends along the tip circle of the large diameter gear 42, the oil O accumulated in the first oil receiving portion 69 is efficiently scraped up to the upper side.

The first oil receiving portion 69 is provided on the lower side of the

intermediate gears

42 and 43 in the range of an angle θ centered on the intermediate shaft J4 when viewed in the axial direction of the motor shaft J2. The angle θ is preferably 120 ° or more and 140 ° or less. By setting the angle θ to 120 ° or more, the oil O can be sufficiently accumulated on the lower side of the

intermediate gears

42 and 43. Further, by setting the angle θ to 140 ° or less, the storage amount of the oil O accumulated in the first oil receiving portion 69 does not become excessive. Therefore, the decrease in the rotation efficiency of the large diameter gear 42 can be suppressed by the oil O accumulated in the first oil receiving portion 69.

In the present embodiment, the first oil receiving portion 69 extends along a tip circle of the large diameter gear 42 of the pair of

intermediate gears

42 and 43. However, the first oil receiving portion 69 may extend along the tip circle of the small diameter gear 43. The small diameter gear 43 meshes with the ring gear 51 disposed adjacent in the horizontal direction. Therefore, when the first oil receiving portion 69 is provided along the tip circle of the small diameter gear 43, the first oil receiving portion 69 is made large to prevent interference between the first oil receiving portion 69 and the ring gear 51. It is difficult to do. On the other hand, in the case where the first oil receiving portion 69 is provided along the tip circle of the large diameter gear 42, interference is facilitated by axially shifting the first oil receiving portion 69 and the ring gear 51. It can be suppressed. The large diameter gear 42 is larger in diameter than the small diameter gear 43. Therefore, the oil O accumulated in the first oil receiving portion 69 can be efficiently scraped up. From the above reasons, it is preferable that the first oil receiving portion 69 extend along the tip circle of the large diameter gear 42.

The second oil receiver 93 is located above the intermediate shaft J4 and the differential shaft J5 in the vertical direction. The second oil receiver 93 is located between the intermediate shaft J4 and the differential shaft J5 in the vehicle front-rear direction (that is, the horizontal direction). The second oil receiver 93 is disposed on the horizontal side of the pinion gear 41. That is, the second oil receiving portion 93 and the shaft 21 are arranged in the horizontal direction. The second oil receiver 93 opens upward. The oil O picked up by the ring gear 51 from the oil reservoir P is collected in the second oil receiving portion 93. The oil O picked up by the large diameter gear (intermediate gear) 42 from the first oil receiving portion 69 is accumulated in the second oil receiving portion 93.

The opening of the second oil receiving portion 93 overlaps the ring gear 51, the large diameter gear 42 and the small diameter gear 43 when viewed from the vertical direction. Most of the oil scooped up by the gear splashes directly above the scooped gear. By arranging the second oil receiving portion 93 immediately above the ring gear 51, the large diameter gear 42 and the small diameter gear 43, the oil O picked up by each gear can be efficiently received.

The second oil receiving portion 93 has a bottom 93a, a first side wall 93b, and a second side wall 93c. The first side wall 93 b and the second side wall 93 c extend upward from the bottom 93 a. The first side wall portion 93 b constitutes a wall surface of the second oil receiving portion 93 on the differential device 5 side. The second side wall portion 93 c constitutes a wall surface of the second oil receiving portion 93 on the reduction gear 4 side. That is, the first side wall 93b extends upward from the end of the bottom 93a on the differential shaft J5 side, and the second side wall 93c extends upward from the end of the bottom 93a on the motor shaft J2 side. The second oil receiver 93 is surrounded by the bottom 93a, the first side wall 93b, the second side wall 93c, and the wall of the gear housing 62 and the projecting plate 61d of the motor housing. Temporarily store oil O in the area.

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 scattered from the opposite side of the reduction gear 4 toward the second oil receiving portion 93. By lowering the height of the upper end portion of the first side wall portion 93b, the oil O scraped up by the differential device 5 can be efficiently stored in the second oil receiving portion 93. Further, the oil O exceeding the first side wall 93b among the oil O scraped up and scattered by the ring gear 51 and the large diameter gear 42 is applied to the second side wall 93c and is guided to the second oil receiving part 93 it can.

The second side wall 93 c extends obliquely upward along the circumferential direction of the pinion gear 41. That is, the second side wall 93c inclines toward the motor shaft J2 as it goes upward. Thus, the second side wall 93 c can receive the oil O scraped up by the differential device 5 in a wide range. In addition, the second side wall 93 c can receive a droplet of oil O which travels along the ceiling of the accommodation space 80 in a wide range.

An oil introduction passage 94 opens toward the inside of the second oil receiving portion 93 at the boundary between the bottom portion 93 a and the second side wall portion 93 c. The bottom 93 a is slightly inclined downward as it goes to the motor axis J 2 in plan view. That is, the bottom 93a is slightly inclined to be the lower end on the second side wall 93c side. Therefore, the oil O in the second oil receiving portion 93 can be efficiently supplied to the oil introduction passage 94 by providing the opening of the oil introduction passage 94 between the bottom 93 a and the second side wall 93 c.

The oil introduction passage 94 extends from the bottom of the second oil receiver 93 toward the shaft 21. The oil introduction passage 94 guides the oil O accumulated in the second oil receiving portion 93 from the end of the shaft 21 to the hollow portion 22. The oil introduction passage 94 extends in a straight line. The oil introduction passage 94 inclines downward from the second oil receiving portion 93 toward the end of the shaft 21. The oil introduction path 94 is formed by processing a linearly extending hole on the wall surface to which the second oil receiving portion 93 of the housing 6 is connected.

The housing 6 has a gear chamber ceiling portion (ceiling portion) 64 that constitutes the upper wall of the gear chamber 82. The gear chamber ceiling 64 is located above the reduction gear 4 and the differential 5. Here, when viewed in the axial direction of the motor axis J2, an imaginary line (third line segment to be described later) L3 is defined which virtually connects the motor axis J2 and the differential axis J5. The gear chamber ceiling 64 is substantially parallel to the virtual line L3. By making the gear chamber ceiling portion 64 substantially parallel to the virtual line L3, a region where oil O which is scraped up by the ring gear 51 and the large diameter gear 42 and scattered in the direction in which the virtual line L3 extends is sufficiently secured. The oil O can be efficiently applied to the pinion gear 41 rotating about the motor axis J2. Further, by making the gear chamber ceiling portion 64 substantially parallel to the virtual line L3, it is possible to suppress the housing 6 from being enlarged in the vertical direction.
In addition, the gear room ceiling part 64 and the virtual line L3 make an angle of the gear room ceiling part 64 and the virtual line L3 to be within 10 degrees as "substantially parallel" here. When the gear chamber ceiling portion 64 is curved, the angle between the tangent line and the imaginary line L3 at all points of the curved line is within 10 °.
In the range of 10 ° or less, the gear chamber ceiling portion 64 preferably approaches the virtual line L3 as it goes from the differential shaft J5 side to the motor shaft J2 side. Thereby, the housing 6 can be miniaturized.

Further, the gear chamber ceiling portion 64 is a curved surface which is slightly curved in a direction approaching the virtual line L3 as it goes from the differential axis J5 side to the motor axis J2 side. The curved shape of the gear chamber ceiling portion 64 is substantially the same as a parabola drawn by the oil O picked up by the ring gear 51 or a curved surface slightly away from the ring gear 51. A portion of the oil O scraped up by the ring gear 51 directly reaches the second oil receiving portion 93. Further, another part of the oil O scraped up by the ring gear 51 travels along the gear chamber ceiling 64 of the housing 6 and reaches the second oil receiver 93. That is, the gear chamber ceiling portion 64 plays a role of guiding the oil O to the second oil receiving portion 93.

The gear chamber ceiling portion 64 has a convex portion 65 projecting downward. The convex portion 65 is located on the upper side of the second oil receiving portion 93. The oil O transmitted to the gear chamber ceiling portion 64 is a large droplet at the lower end of the convex portion 65 and falls downward and is collected in the second oil receiving portion 93. That is, the convex portion 65 guides the oil O transmitted along the gear chamber ceiling portion 64 to the second oil receiving portion 93.
In the present embodiment, the motor housing 61 and the gear housing 62 are fixed to each other by bolts 67. The convex portion 65 is provided in the gear chamber ceiling portion 64 using a thick portion around a screw hole into which the bolt 67 is inserted. In FIG. 2, illustration of other bolts for fixing the motor housing 61 and the gear housing 62 and other thick parts around the screw holes is omitted.

The gear chamber ceiling 64 has a plate-like flange 66 extending along the axial direction. The collar 66 projects downward. The lower end of the collar 66 is located above the second oil receiver 93. A part of the oil O scraped up and scattered by the ring gear 51 strikes the ridge 66 and travels along the surface of the ridge 66. Similarly, the oil O scraped up and scattered by the large diameter gear 42 is received by the flange 66 and travels along the surface of the flange 66. The oil O becomes a large droplet at the lower end of the collar portion 66 and drops downward and accumulates in the second oil receiving portion 93. That is, the collar portion 66 guides the scraped oil O to the second oil receiving portion 93.
The flange portion 66 is inclined from the differential shaft J5 side to the motor shaft J2 side as it goes from the upper side to the lower side. The ring gear 51 has a large diameter as compared with the large diameter gear 42 and the small diameter gear 43, so the scattering angle of the oil O that is scattered is close to horizontal. By disposing the flange 66 in an inclined manner in the above direction, the oil O scattered from the ring gear 51 can be smoothly attached to the surface of the flange 66 and dropped downward.

(Arrangement of each axis)
The motor axis J2, the intermediate axis J4 and the differential axis J5 extend parallel to one another along the horizontal direction. The intermediate shaft J4 and the differential shaft J5 are located below the motor shaft J2. Therefore, the reduction gear 4 and the differential 5 are located below the motor 2.

A line segment virtually connecting the motor axis J2 and the intermediate axis J4 is a first line segment L1 when viewed from the axial direction of the motor axis J2, and a line segment virtually connecting the intermediate axis J4 and the differential axis J5 Is a second line segment L2, and a line segment that virtually connects the motor axis J2 and the differential axis J5 is a third line segment L3.

According to the present embodiment, the second line segment L2 extends along the substantially horizontal direction. That is, the intermediate shaft J4 and the differential shaft J5 are aligned substantially in the horizontal direction. Therefore, the reduction gear 4 and the differential device 5 can be arranged in the horizontal direction, and the size of the motor unit 1 in the vertical direction can be reduced. Further, the oil O scraped up by the differential device 5 can be efficiently applied to the reduction gear 4. Thereby, oil O can be supplied to the tooth surface of the gear which comprises the reduction gear 4, and the transmission efficiency of a gear can be raised. The diameter of the gears (the large diameter gear 42 and the small diameter gear 43) rotating about the intermediate shaft J4 is smaller than the diameter of the ring gear 51 rotating about the differential shaft J5. According to this embodiment, since the second line segment L2 extends along the substantially horizontal direction, the intermediate axis J4 and the differential axis J5 are disposed along the substantially horizontal direction. Therefore, depending on the liquid level of the oil reservoir P, only the ring gear 51 is immersed in the oil reservoir P, and the large diameter gear 42 and the small diameter gear 43 are not immersed in the oil reservoir P. Therefore, while the oil O of the oil reservoir P is scooped up by the ring gear 51, it is possible to suppress the decrease in the rotational efficiency of the large diameter gear 42 and the small diameter gear 43.
In the present embodiment, the substantially horizontal direction of the second line segment L2 is a direction within ± 10 ° with respect to the horizontal direction.

According to the present embodiment, an angle α between the second line segment L2 and the third line segment L3 is 30 ° ± 5 °. As a result, the transmission efficiency between the pinion gear 41 and the large diameter gear 42 of the oil O scraped up by the differential device 5 can be enhanced, and a desired gear ratio can be realized.
If the angle α exceeds 35 °, it becomes difficult to supply the oil scraped up by the differential device to the gear (pinion gear) that rotates about the motor shaft. As a result, the transmission efficiency between the pinion gear and the large diameter gear may be reduced. On the other hand, if the angle α is less than 25 °, the output side gear in the transmission process can not be made sufficiently large, and the desired gear ratio is achieved in three axes (motor shaft, intermediate shaft and differential shaft) It becomes difficult.

According to the present embodiment, the first line segment L1 extends along the substantially vertical direction. That is, the motor shaft J2 and the intermediate shaft J4 are aligned along the substantially vertical direction. Therefore, the motor 2 and the reduction gear 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 disposed close to the differential shaft J5, and the pinion gear 41 that rotates about the motor shaft J2 is a differential gear. It is possible to supply the oil O scraped up with 5. Thereby, the transmission efficiency between the pinion gear 41 and the large diameter gear 42 can be enhanced.
In the present embodiment, the substantially vertical direction of the first line segment L1 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 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.

<Oil>
The oil O is used to lubricate the reduction gear 4 and the differential gear 5. The oil O is also used for cooling the motor 2. The oil O accumulates in the lower region (i.e., oil reservoir P) in the gear chamber 82. It is preferable to use an oil O equivalent to a low viscosity lubricating oil for automatic transmission (ATF: Automatic Transmission Fluid) in order to perform the functions of a lubricating oil and a cooling oil.

As shown in FIG. 1, the oil O circulates in the oil passage 90 in the motor unit 1. The oil path 90 is a path of oil O which supplies the oil O from the oil reservoir P to the motor 2.

In the present specification, the “oil passage” means a passage of oil O circulating in the storage space 80. Therefore, the "oil path" is not only a "flow path" that forms a steady flow of oil in one direction in a steady manner, but also a path (for example, a reservoir) for temporarily retaining oil and dripping oil It is a concept that also includes the route.

The oil passage 90 is located inside the housing 6, that is, in the storage 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 path 90 is a path of the oil O which leads the oil O from the oil reservoir P through the motor 2 to the oil reservoir P again. 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 first oil passage 91 and the second oil passage 92 are paths for supplying the oil O from the oil reservoir P to the motor 2 and recovering the oil O in the oil reservoir P again. In the first oil passage 91 and the second oil passage 92, the oil O drips from the motor 2 and accumulates in the lower region in the motor chamber 81. The oil O accumulated in the lower region in the motor chamber 81 moves to the lower region (i.e., the oil reservoir P) in the gear chamber 82 through the partition opening 68.

In the path of the first oil passage 91, a cooler 97 for cooling the oil O is provided. The oil O passing through the first oil passage 91 and cooled by the cooler 97 merges with the oil O passing through the second oil passage 92 in the oil reservoir P. In the oil reservoir P, the oils O which have passed through the first oil passage 91 and the second oil passage 92 are mixed with each other to perform heat exchange. Therefore, the oil O which is disposed in the path of the first oil passage 91 and cools the cooler 97 can be exerted also on the oil O passing through the second oil passage 92. According to this 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 disposed in the flow path in which the liquid constantly flows. In order to cool the two oil passages, a configuration is conceivable in which a cooler is disposed in each of the flow passages 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 passage in a region where the two oil passages are joined and install a cooler in the flow passage. In this case, since it is necessary to provide a flow path in the alternating current area, the structure of the flow path in the oil path needs to be complicated, resulting in an increase in cost.
According to the present embodiment, the 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 reservoir P, whereby the second The oil passage 92 can be indirectly cooled. Thus, 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 passage in the oil passage 90.
In addition, such an effect has the cooler 97 which cools the oil O in any one of the 1st oil path 91 and the 2nd oil path 92, and the 1st oil path 91 and the 2nd oil This is an effect that can be achieved when the oil O flowing through the passage 92 joins at the oil reservoir P.

The heat of the oil O is dissipated mainly through the cooler 97. Further, part of the heat of the oil O is also dissipated through the housing 6 because the oil O contacts the inner surface of the housing 6. In addition, as shown in FIG. 1, the uneven heat sink part 6b may be provided in the outer surface of the housing 6. As shown in FIG. The heat sink portion 6 b promotes cooling of the motor 2 via the housing 6.

(First oil path)
In the first oil passage 91, the oil O is scooped up from the oil reservoir P by the differential device 5 and guided to the inside of the rotor 20. The oil O is given a centrifugal force associated with the rotation of the rotor 20 inside the rotor 20. Thus, the oil O is uniformly diffused toward the stator 30 surrounding the rotor 20 from the radial outer side, and cools the stator 30.

The first oil passage 91 has a scraping passage 91a, an oil supply passage 91b, an in-shaft passage 91c, and an in-rotor passage 91d. In addition, in the path of the first oil passage 91, a second oil receiving portion 93 is provided. The second oil receiving portion 93 is provided in the housing space 80 (in particular, the gear chamber 82).

The scraping path 91a is a path for scraping the oil O from the oil reservoir P by the rotation of the ring gear 51 and the large diameter gear 42 and receiving the oil O at the second oil receiving portion 93 (see FIG. 2). The scraping path 91a has a first scraping path 91aa and a second scraping path 91ab. Whether the oil O passes through the first raking path 91 aa or the second raking path 91 ab is determined depending on the rotational direction of the motor 2.

As shown in FIG. 2, the motor 2 rotates in a first rotation direction T1 and a second rotation direction T2. In FIG. 2, the solid line indicates the rotational direction of each gear when the motor 2 rotates in the first rotational direction T1, and the rotational direction of each gear when the motor 2 rotates in the second rotational direction T2 It shows with a dashed dotted line.

In the present embodiment, a case where the motor unit 1 causes the vehicle to move forward when the motor 2 rotates in the first rotation direction T1 and causes the motor 2 to reverse the vehicle in the second rotation direction T2 will be described. However, when the motor 2 rotates in the first rotation direction T1, the motor unit 1 may cause the vehicle to move backward, and the motor 2 may move the vehicle forward in the second rotation direction T2.

When the motor 2 rotates in the first rotation direction T1, the oil O is supplied to the second oil receiving portion 93 through the first scraping path 91aa. Further, when the motor 2 is rotated in the second rotational direction T2, the oil O is supplied to the second oil receiving portion 93 through the second scraping path 91ab.

First, the case where the motor 2 is rotated in the first rotation direction T1 and the oil O is supplied to the second oil receiving portion 93 through the first scraping path 91aa will be described.

In the present embodiment, the differential shaft J5, which is the rotation center of the ring gear 51, is disposed on the vehicle rear side with respect to the reduction gear 4. The ring gear 51 rotates upward in a region opposite to the reduction gear 4 when the motor 2 rotates in the first rotation direction T1. The ring gear 51 scoops the oil O accumulated on the lower side of the gear chamber 82 upward in the vertical direction.

The oil O scraped up from the oil reservoir P by the rotation of the ring gear 51 falls from the upper side of each gear (the pinion gear 41, the large diameter gear 42 and the small diameter gear 43) in the gear chamber 82 and is supplied to the tooth surface of each gear. . Thereby, the transmission efficiency of the power of each gear can be improved.

The oil O scraped up by the rotation of the ring gear 51 falls on the upper side of the second oil receiver 93 around the opposite side of the reduction gear 4 and is collected in the second oil receiver 93. That is, when the motor 2 rotates in the first rotation direction T1, the second oil receiving portion 93 receives the oil O scraped up by the rotation of the ring gear 51 from the oil reservoir P. When the liquid level of the oil reservoir P is high immediately after the motor 2 is driven, the pair of intermediate gears (large diameter gear 42 and small diameter gear 43) contact the oil O of the oil reservoir P and scoop the oil O. In such a case, the second oil receiving portion 93 receives not only the ring gear 51 but also the oil O scraped up by the large diameter gear 42 and the small diameter gear 43.

Next, the case where the motor 2 rotates in the second rotation direction T2 and the oil O is supplied to the second oil receiving portion 93 through the second scraping path 91ab will be described.

The ring gear 51 of the differential device 5 rotates upward in a region on the side of the reduction gear 4 when the motor 2 rotates in the second rotation direction T2. The ring gear 51 scrapes the oil O accumulated in the oil reservoir P upward in the vertical direction. The oil O scraped up by the rotation of the ring gear 51 is collected in the first oil receiving portion 69 located below the

intermediate gears

42, 43.

The intermediate gears 42 and 43 of the reduction gear 4 rotate upward in the region on the differential device 5 side when the motor 2 rotates in the second rotation direction T2. The large diameter gear 42 which is one of the pair of

intermediate gears

42 and 43 scoops the oil O accumulated in the first oil receiving portion 69 upward in the vertical direction.

The oil O scraped up by the rotation of the large diameter gear 42 descends from the upper side of each gear (the pinion gear 41 and the small diameter gear 43) in the gear chamber 82 and is supplied to the tooth surface of each gear. Thereby, the transmission efficiency of the power of each gear can be improved.

Further, the oil O scraped up by the rotation of the large diameter gear 42 passes between the reduction gear 4 and the differential device 5 and falls on the upper side of the second oil receiving portion 93 and accumulates in the second oil receiving portion 93. . That is, when the motor 2 is rotated in the second rotation direction T2, the second oil receiver 93 receives the oil O picked up by the large diameter gear 42 from the first oil receiver 69.

According to this embodiment, the oil O can be scooped up by the gear even when the motor 2 rotates in any direction. Therefore, the oil O can be spread over the tooth surfaces of the gears whether the vehicle is moving forward or backward. Further, the oil O can be spread over the tooth surface of each gear regardless of whether the rotation direction of the motor 2 for advancing the vehicle is the first rotation direction T1 or the second rotation direction T2. . Therefore, the degree of freedom of the attitude of the motor unit 1 with respect to the vehicle can be enhanced. Further, according to the present embodiment, even when the motor 2 rotates in any direction, the oil O can be accumulated in the second oil receiving portion 93 by scraping the oil O with the gear. As described later, the oil O stored in the second oil receiving portion 93 is supplied to the motor 2 to cool the motor 2. That is, regardless of the rotation direction of the motor 2, the motor 2 can be cooled efficiently.

In the present embodiment, the second oil receiving portion 93 and the shaft 21 are arranged in the horizontal direction. Therefore, the second oil receiving portion 93 and the pinion gear 41 are disposed at the same height. Therefore, the scraping height of the oil O for storing the oil O in the second oil receiving portion 93 and the scraping height of the oil O for supplying the oil O to the tooth surface of the pinion gear 41 substantially coincide with each other. . Therefore, the oil O can be supplied to the second oil receiving portion 93 and the oil O can be efficiently supplied to the tooth surface of the pinion gear 41 by scraping the oil O by the gears.

Further, the second oil receiving portion 93 of the present embodiment is located between the intermediate shaft J4 and the differential shaft J5 in the horizontal direction. That is, the second oil receiving portion 93 is disposed at a position where the oil O is susceptible to being scooped up against the oil O of both the large diameter gear 42 and the ring gear 51. Therefore, the oil O can be efficiently received by the second oil receiving portion 93 against the scraping of the oil O by the large diameter gear 42 and the ring gear 51.

As shown in FIG. 1, the oil supply flow passage 91 b guides the oil O to the motor 2 from the second oil receiving portion 93. The oil supply passage 91 b is constituted by the oil introduction passage 94.

The shaft inner path 91 c is a path through which the oil O passes in the hollow portion 22 of the shaft 21. Further, the rotor inner path 91 d is a path which passes through the inside of the rotor core 24 from the communication hole 23 of the shaft 21 and scatters to the stator 30.

In the shaft inner path 91 c, centrifugal force is applied to the oil O inside the rotor 20 as the rotor 20 rotates. Thus, the oil O continuously splashes radially outward from the end plate 26. In addition, as the oil O is scattered, the pressure in the path inside the rotor 20 becomes negative pressure, and the oil O accumulated in the second oil receiving portion 93 is sucked into the rotor 20 and the oil O flows in the path inside the rotor 20 It is filled.

The oil O that has reached the stator 30 removes heat from the stator 30. The oil O which has cooled the stator 30 is dropped downward, and is accumulated in the lower region in the motor chamber 81. The oil O accumulated in the lower region in the motor chamber 81 moves to the gear chamber 82 through the partition opening 68 provided in the partition 61 c.

According to the present embodiment, the first oil passage 91 includes the scraping path 91a and the rotor inner path 91d. The scraping path 91 a moves the oil O from the gear chamber 82 to the motor chamber 81 by scraping the oil O by the differential device 5. The amount of oil O picked up by the differential 5 depends on the number of revolutions of the differential 5. Therefore, the scraping path 91a increases or decreases the amount of movement of the oil O to the motor chamber 81 depending on the vehicle speed. Further, the rotor inner path 91 d sucks the oil O from the gear chamber 82 side to the motor chamber 81 side by the centrifugal force of the rotor 20. The centrifugal force depends on the rotational speed of the rotor 20. Therefore, the rotor inner path 91d increases or decreases the amount of movement of the oil O to the motor chamber 81 depending on the vehicle speed. That is, in the first oil passage 91, the amount of movement of the oil O to the motor chamber 81 increases or decreases depending on the vehicle speed.

(Second oil path)
As shown in FIG. 1, the oil O is pulled up from the oil reservoir P to the upper side of the motor 2 in the second oil passage 92 and supplied to the motor 2. The oil O supplied to the motor 2 takes heat from the stator 30 while cooling along the outer peripheral surface of the stator 30 to cool the motor 2. The oil O transmitted along the outer peripheral surface of the stator 30 drips downward and accumulates in the lower region in the motor chamber 81. The oil O of the second oil passage 92 merges with the oil O of the first oil passage 91 in the lower region of the motor chamber 81. The oil O accumulated in the lower region in the motor chamber 81 moves to the lower region (i.e., the oil reservoir P) in the gear chamber 82 through the partition opening 68.

The second oil passage 92 has a first flow passage 92a, a second flow passage 92b, and a third flow passage 92c. In the path of the second oil passage 92, a pump 96, a cooler 97, and a reservoir 98 are provided. In the second oil passage 92, the oil O passes through each portion in the order of the first passage 92a, the pump 96, the second passage 92b, the cooler 97, the third passage 92c, and the reservoir 98, It is supplied to the motor 2.

The first flow passage 92 a, the second flow passage 92 b and the third flow passage 92 c pass through the inside of the wall 6 a of the housing 6 surrounding the accommodation space 80. The first flow path 92 a connects the oil reservoir P and the pump 96. The second flow path 92 b connects the pump 96 and the cooler 97. The third flow path 92 c connects the cooler 97 and the storage space 80.

The pump 96 is an electric pump driven by electricity. The pump 96 sucks up the oil O from the oil reservoir P via the first flow passage 92a and supplies it to the motor 2 via the second flow passage 92b, the cooler 97, the third flow passage 92c and the reservoir 98. .

The amount of oil O supplied to the motor 2 by the pump 96 is appropriately controlled in accordance with the driving state of the motor 2. Therefore, when the temperature of the motor 2 is increased, for example, when a long time drive or a high output is required, the drive output of the pump 96 is increased and the amount of oil O supplied to the motor 2 is increased.

The cooler 97 is connected to a first flow passage 92 a and a second flow passage 92 b. The first flow path 92 a and the second flow path 92 b are connected via the internal flow path of the cooler 97. 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 cooled by heat exchange with the cooling water.

The reservoir 98 is located in the motor chamber 81 of the accommodation space 80. The reservoir 98 is located above the motor. The reservoir 98 stores oil O supplied to the motor chamber 81 via the third flow path 92c. The reservoir 98 has a plurality of outlets 98a. The oil O accumulated in the reservoir 98 is supplied to the motor 2 from each outlet 98 a. The oil O flowing out from the outlet 98 a of the reservoir 98 flows from the upper side to the lower side along the outer peripheral surface of the motor 2 to remove the heat of the motor 2. Thereby, the whole motor 2 can be cooled.

The reservoir 98 extends along the axial direction. The outlets 98 a of the reservoir 98 are provided at both axial ends of the reservoir 98. The outlet 98a is located above the coil end 31a. As a result, oil O can be applied to the coil ends 31a located at both axial ends of the stator 30 to directly cool the coils 31.

The oil O which has cooled the coil 31 is dropped downward, and is accumulated in the lower region in the motor chamber 81. The oil O accumulated in the lower region in the motor chamber 81 moves to the gear chamber 82 through the partition opening 68 provided in the partition 61 c.

According to this embodiment, the second oil passage 92 moves the oil O 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 based on, for example, the temperature measurement result of the motor 2. Therefore, in the second oil passage 92, the amount of movement of the oil O 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 at rest. The second oil passage 92 starts the movement of the oil O to the motor chamber 81 when the motor 2 is started. Therefore, the liquid level of the oil reservoir P in the gear chamber 82 can be raised at the time of stop. As a result, the large diameter gear 42, the small diameter gear 43 and the ring gear 51 can be rotated in the oil reservoir P by the rotation of the motor 2 immediately after start-up, so that the oil O can spread over the tooth surface.

(Modification)
The introduction structure of the oil O into the shaft 121 which can be adopted in the above embodiment will be described as a modification. FIG. 3 is a conceptual view showing the tip of the shaft 121 and the second oil receiver 193 in the motor unit of the modification.
In addition, about the component of the aspect same as the above-mentioned embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

As in the above-described embodiment, the oil O is supplied to the second oil receiver 193 through the first scraping path 91 aa and the second scraping path 91 ab. More specifically, the second oil receiving portion 193 is scooped up by the rotation of the large diameter gear 42 from the oil O scraped up by the rotation of the ring gear 51 from the oil reservoir P and the first oil receiving portion 69. Oil accumulates (see Figure 1).

The shaft 121 rotating around the motor axis J2 is a hollow shaft. That is, the shaft 121 is provided with a hollow portion 122 extending along the motor axis J2. The tip of the shaft 121 is closed. Further, the tip of the shaft 121 is accommodated in the second oil receiver 193. That is, at least a part of the second oil receiver 193 surrounds a part of the outer periphery of the shaft 121.

The shaft 121 is provided with a through hole 121 a connecting the outside of the shaft 121 and the hollow portion 122 in a region surrounded by the second oil receiving portion 193. The through holes 121a extend in the radial direction. The through hole 121 a introduces the oil O accumulated in the second oil receiving portion 193 into the inside (hollow portion 122) of the shaft 121.

According to this modification, even if the housing is not provided with the flow passage (corresponding to the oil introduction passage 94 shown in FIG. 1) connecting the second oil receiving portion 193 and the inside of the shaft 121 in the housing, the shaft Oil O can be introduced into the inside of 121.

Second Embodiment
Next, a motor unit 201 of the second embodiment will be described.
FIG. 4 is a side view of the motor unit 201. As shown in FIG. FIG. 5 is a cross-sectional view of the motor unit 201 taken along the line VV of FIG. The motor unit 201 according to the second embodiment mainly differs in the configuration of the housing 206 from the above-described embodiment.
In addition, about the component of the aspect same as the above-mentioned embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

The motor unit 201 includes the motor 2 (omitted in FIGS. 4 and 5), the reduction gear 204, the differential device 5, the housing 206, and the oil O, as in the above-described embodiment. Also, the motor unit 201 of the present embodiment has an inverter 203.

The reduction gear 204 has a pinion gear 41, an intermediate shaft 45, and a pair of

intermediate gears

42 and 43 fixed to the intermediate shaft 45, as in the above-described embodiment. The pair of

intermediate gears

42 and 43 are classified into the large diameter gear 42 and the small diameter gear 43. The torque output from the motor 2 is transmitted to the ring gear 51 of the differential 5 through the shaft 21 of the motor 2, the pinion gear 41, and the pair of

intermediate gears

42 and 43.

Inside the housing 206, a housing space 80 for housing the motor 2, the reduction gear 204 and the differential 5 is provided. The housing space 80 is divided into a motor chamber 81 (not shown in FIGS. 4 and 5) for housing the motor 2 and a gear chamber 82 for housing the reduction gear 204 and the differential device 5.

In the lower region of the gear chamber 82, an oil reservoir P in which the oil O is accumulated is provided. A part of the differential device 5 is immersed in the oil reservoir P. That is, at least a part of the ring gear 51 is immersed in the oil O accumulated in the oil reservoir P.

As shown in FIG. 5, the housing 206 has a first member 206A and a second member 206B. The first member 206A and the second member 206B are aligned along the axial direction. The first member 206A has a concave shape that opens in the axial direction toward the second member 206B. Similarly, the second member 206B has a concave shape that opens in the axial direction toward the first member 206A. The first member 206A and the second member 206B face each other to form a gear chamber 82. That is, the first member 206A and the second member 206B surround the gear chamber 82. The first member 206A has a first facing surface (facing surface) 206Aa that constitutes an inner wall surface facing in the axial direction of the gear chamber 82. Similarly, the second member 206B has a second facing surface (facing surface) 206Ba that constitutes an inner wall surface facing the axial direction of the gear chamber 82. The first facing surface 206Aa and the second facing surface 206Ba face each other in the axial direction.

As shown in FIG. 4, the housing 206 includes a first oil receiving portion 269, a second oil receiving portion 293, a first oil guiding portion 265, a second oil guiding portion 266, and an oil introducing passage. And 94. The first oil receiving portion 269, the second oil receiving portion 293, the first oil guiding portion 265, the second oil guiding portion 266, and the oil introducing passage 94 are disposed in the gear chamber 82. The first oil receiver 269 and the second oil receiver 293 open upward. The first oil receiver 269 and the second oil receiver 293 function as a reservoir for temporarily storing oil. The first oil guiding portion 265 and the second oil guiding portion 266 induce the oil O in the gear chamber 82. The oil introduction path 94 connects the second oil receiving portion 293 and the inside of the shaft 21.

The first oil receiving portion 269 is located below the large diameter gear 42 and extends in an arc along the tip circle of the large diameter gear 42. The oil O picked up by the ring gear 51 is accumulated in the first oil receiving portion 269.

The first oil receiving portion 269 overlaps the large diameter gear 42 in the axial direction. A part of the large diameter gear 42 is immersed in the oil O accumulated in the first oil receiving portion 269. The oil O accumulated in the first oil receiving portion 269 is scooped up by the rotation of the large diameter gear 42. Since the first oil receiving portion 269 extends along the tip circle of the large diameter gear 42, the oil O accumulated in the first oil receiving portion 269 is efficiently scraped upward.

As shown in FIG. 5, the first oil receiving portion 269 is composed of a first rib 269a and a second rib 269b. The first rib 269a is provided on the first member 206A, and the second rib 269b is provided on the second member 206B. That is, the first member 206A has a first rib 269a, and the second member 206B has a second rib 269b.

The first rib 269a protrudes from the first opposing surface 206Aa of the first member 206A in a substantially uniform cross-sectional shape in the axial direction. The second rib 269b axially protrudes from the second opposing surface 206Ba of the second member 206B. The first rib 269a and the second rib 269b abut each other. Thus, the first rib 269a and the second rib 269b constitute a first oil receiving portion 269.

According to the present embodiment, the first oil receiving portion 269 is composed of the first rib 269a and the second rib 269b. The first oil receiving portion 269 is surrounded from both sides in the axial direction by the first opposing surface 206Aa of the first member 206A and the second opposing surface 206Ba of the second member 206B. As a result, the oil O can be reliably stored in the first oil receiving portion 269.

According to the present embodiment, the first oil receiving portion 269 extends in the axial direction from the first facing surface 206Aa to the second facing surface 206Ba. That is, the first oil receiving portion 269 is disposed over the entire length of the gear chamber 82 in the axial direction. Therefore, the first oil receiving portion 269 overlaps not only the large diameter gear 42 but also the ring gear 51 in the axial direction. Therefore, the first oil receiving portion 269 can efficiently receive the oil O scraped up by the ring gear 51.

In the present embodiment, the first oil receiver 269 is configured as a part of the first member 206A and the second member 206B. However, the first oil receiver 269 may be a separate member fixed to the first member 206A or the second member 206B.

As shown in FIG. 4, the first oil guiding portion 265 extends in the shape of a rib along the vertical direction. The first oil guiding portion 265 extends in an arc along the tip of the small diameter gear 43. As shown in FIG. 5, the first oil guiding portion 265 axially protrudes from the first opposing surface 206Aa of the first member 206A. The first oil guiding portion 265 is located immediately above the first oil receiving portion 269. That is, the first oil guiding portion 265 is located on the upper side of the first oil receiving portion 269, and at least a part thereof overlaps the first oil receiving portion 269 when viewed in the vertical direction.

According to the present embodiment, the first oil guiding portion 265 overlaps the ring gear 51 in the axial direction. Therefore, the oil O scraped up by the ring gear 51 hits the first oil guiding portion 265. Since the first oil guiding portion 265 is positioned immediately above the first oil receiving portion 269, the oil O that has hit the first oil guiding portion 265 is dropped to the first oil receiving portion 269.

As shown in FIG. 4, the second oil guiding portion 266 extends in the shape of a rib along the vertical direction. The second oil guiding portion 266 extends in an arc along the tip circle of the large diameter gear 42. The second oil guiding portion 266 is located on the side of the differential shaft J5 in the horizontal direction with respect to the large diameter gear 42. The second oil guiding portion 266 overlaps the large diameter gear 42 in the axial direction. Further, the second oil guiding portion 266 overlaps with a second oil receiving portion 293 described later in the axial direction.

According to the present embodiment, the second oil guiding portion 266 overlaps the large diameter gear 42 in the axial direction. For this reason, the oil O scraped up by the large diameter gear 42 hits the second oil guiding portion 266. The second oil guiding portion 266 guides the oil O scraped up by the large diameter gear 42 to the second oil receiving portion 293.

As shown in FIG. 5, the second oil guiding portion 266 axially protrudes from the second opposing surface 206Ba of the second member 206B. The second oil guiding portion 266 does not overlap with the ring gear 51 in the axial direction. For this reason, the second oil guiding portion 266 does not disturb the path of the oil O which is scooped up by the ring gear 51 and received by the first oil receiving portion 269.

As shown in FIG. 4, the second oil receiving portion 293 is located above the intermediate axis J4 and the differential axis J5 in the vertical direction. The second oil receiver 293 is located between the intermediate shaft J4 and the differential shaft J5 in the longitudinal direction of the vehicle (ie, in the horizontal direction). The second oil receiver 293 is disposed on the horizontal side of the pinion gear 41. That is, the second oil receiving portion 293 and the shaft 21 are arranged in the horizontal direction. The second oil receiver 293 opens upward.

In the second oil receiving portion 293, the oil O scraped up by the ring gear 51 from the oil reservoir P is collected. In the second oil receiving portion 293, the oil O scraped up by the large diameter gear (intermediate gear) 42 from the first oil receiving portion 269 is collected.

As shown in FIG. 5, the second oil receiving portion 293 is configured by abutting a pair of ribs 293c and 293d axially protruding from the first opposing surface 206Aa and the second opposing surface 206Ba. Therefore, the second oil receiver 293 is disposed along the entire axial length of the gear chamber 82. The second oil receiver 293 overlaps the large diameter gear 42 and the ring gear 51 in the axial direction. Therefore, the second oil receiving portion 293 can efficiently receive the oil O scraped up by the large diameter gear 42 and the ring gear 51.

As shown in FIG. 4, the second oil receiver 293 has a bottom 293a and a side wall 293b extending upward from the bottom 293a. Second oil receiving portion 293 temporarily stores oil O in a region surrounded by bottom portion 293a and side wall portion 293b.

Side wall portion 293 b includes a first wall portion 293 ba and a second wall portion 293 bb. The first wall portion 293ba and the second wall portion 293bb extend upward from the bottom portion 293a, respectively. The first wall portion 293 ba constitutes a wall surface of the second oil receiving portion 293 on the differential device 5 side. The second wall portion 293bb constitutes a wall surface of the second oil receiving portion 293 on the side of the reduction gear 204. That is, the first wall portion 293ba extends upward from the end portion of the bottom portion 293a on the differential shaft J5 side, and the second wall portion 293bb extends upward from the end portion of the bottom portion 293a on the motor axis J2 side. The upper end of the first wall 293ba is located below the upper end of the second wall 293bb.

The first wall portion 293ba faces the second oil guiding portion 266 in the horizontal direction. Further, the upper end of the first wall 293 ba is located below the upper end of the second oil guiding portion 266. That is, the upper end of the second oil guiding portion 266 extends above the first wall portion 293ba. For this reason, the oil O which is scooped up by the large diameter gear 42 and hits the second oil guiding portion 266 is smoothly guided to the second oil receiving portion 293.

The second wall portion 293bb extends obliquely upward along the circumferential direction of the pinion gear 41. That is, the second wall portion 293bb inclines toward the motor axis J2 as it goes upward. Thereby, the second wall portion 293bb can receive the oil O scraped up by the ring gear 51 and the large diameter gear 42 in a wide range.

As shown in FIG. 2, the pinion gear 41 (i.e., the motor 2) is rotatable in a first rotation direction T1 and a second rotation direction T2. The motor unit 201 can be considered to drive the front wheels of the vehicle and drive the rear wheels of the vehicle. Motor unit 201 is arranged with inverter 203 directed to the inside of the vehicle from the viewpoint of protection of inverter 203. Therefore, in the motor unit 201, when the vehicle moves forward, the case where the pinion gear 41 rotates in the first rotation direction T1 and the case where the pinion gear 41 rotates in the second rotation direction T2 are assumed.

When the pinion gear 41 rotates in the first rotation direction T1, the ring gear 51 rotates upward in a region opposite to the reduction gear 204. The ring gear 51 scoops the oil O accumulated on the lower side of the gear chamber 82 upward in the vertical direction.

Further, the oil O scraped up by the rotation of the ring gear 51 falls on the upper side of the second oil receiving portion 293 around the opposite side of the reduction gear 204 and is collected in the second oil receiving portion 293. That is, when the pinion gear 41 is rotated in the first rotation direction T1, the second oil receiver 293 receives the oil O scraped up by the rotation of the ring gear 51 from the oil reservoir P.

When the pinion gear 41 rotates in the second rotation direction T2, the ring gear 51 rotates upward in a region on the reduction gear 204 side. The ring gear 51 scrapes the oil O accumulated in the oil reservoir P upward in the vertical direction. The oil O scraped up by the rotation of the ring gear 51 drops on the first oil guiding portion 265 and drops in a first oil receiving portion 269 located below the large diameter gear 42.

The large diameter gear 42 rotates upward in the region on the differential device 5 side when the pinion gear 41 rotates in the second rotation direction T2. The large diameter gear 42 scrapes the oil O accumulated in the first oil receiving portion 269 upward in the vertical direction.

Further, the oil O scraped up by the rotation of the large diameter gear 42 is guided to the second oil guiding portion 266, falls on the upper side of the second oil receiving portion 293, and is accumulated in the second oil receiving portion 293. That is, the second oil receiver 293 receives the oil O picked up by the large diameter gear 42 from the first oil receiver 269 when the pinion gear 41 rotates in the second rotation direction T2.

According to the present embodiment, even when the pinion gear 41 rotates in any direction, the oil O can be scooped up by the gear. Therefore, the oil O can be spread over the tooth surfaces of the gears whether the vehicle is moving forward or backward. Further, the oil O can be spread over the tooth surface of each gear regardless of whether the rotation direction of the pinion gear 41 for advancing the vehicle is the first rotation direction T1 or the second rotation direction T2. . Therefore, the degree of freedom of the attitude of the motor unit 201 with respect to the vehicle can be enhanced. That is, even if it is a front wheel drive vehicle or a rear wheel drive vehicle, the common motor unit 201 can be adopted.

Further, according to the present embodiment, even when the pinion gear 41 rotates in any direction, the oil O can be accumulated in the second oil receiving portion 293 by scraping the oil O with the gear. The oil O accumulated in the second oil receiver 293 is supplied to the motor 2 to cool the motor 2. That is, regardless of the rotation direction of the motor 2, the motor 2 can be cooled efficiently.

The motor axis J2, the intermediate axis J4 and the differential axis J5 extend parallel to one another along the horizontal direction. The intermediate shaft J4 and the differential shaft J5 are located below the motor shaft J2. Therefore, the reduction gear 204 and the differential 5 are located below the motor 2.

As shown in FIG. 4, when viewed in the axial direction of the motor axis J2, a line segment virtually connecting the motor axis J2 and the intermediate axis J4 is defined as a first line segment L1, and the intermediate axis J4 and the differential axis J5 Is a second line segment L2, and a line segment virtually connecting the motor axis J2 and the differential axis J5 is a third line segment L3.

The second line segment L2 extends in the range of ± 30 ° or less with respect to the substantially horizontal direction. According to the present embodiment, the reduction gear 204 and the differential device 5 can be arranged in the horizontal direction, and the size of the motor unit 201 in the vertical direction can be reduced. Further, according to the present embodiment, the oil O scraped up by the differential device 5 can be efficiently applied to the reduction gear 204. Thereby, oil O can be supplied to the tooth surface of the gear which comprises the reduction gear 204, and the transmission efficiency of a gear can be raised.

The first line segment L1 extends in a direction within ± 30 ° with respect to the vertical direction. According to this embodiment, the motor 2 and the reduction gear 204 can be arranged along the vertical direction, and the dimension of the motor unit 201 in the horizontal direction can be reduced. Further, according to the present embodiment, the motor shaft J2 can be disposed close to the differential shaft J5, and the oil O picked up by the differential device 5 is held in the pinion gear 41 rotating about the motor shaft J2. It can be supplied. Thereby, the transmission efficiency between the pinion gear 41 and the large diameter gear 42 can be enhanced.

In the present embodiment, 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 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.

Although the embodiments and modifications of the present invention have been described above, the respective configurations and combinations thereof in the embodiments are merely examples, and additions, omissions, replacements, and configurations of the configurations are possible within the scope of the present invention. Other modifications are possible. Further, the present invention is not limited by the embodiments.

1, 201: motor unit, 2: motor, 4, 204: reduction gear, 5: differential device, 6, 206: housing, 21, 121: shaft, 41: pinion gear, 42: large diameter gear (intermediate gear), 43 small diameter gear (intermediate gear) 51

ring gear

69, 269 first oil receiving portion 80 housing space 81 motor chamber 82

gear chamber

93, 193, 293 second oil receiver Part: 94 Oil introduction path 121a Through hole 206A first member 206Aa first opposing surface (opposite surface) 206B second member 206Ba second opposing surface (opposite surface) 265 ... 1st oil induction part, 266 ... 2nd oil induction part, 293a ... bottom part, 293b ... side wall part, 293ba ... 1st wall part, 293bb ... 2nd wall part, 296a ... 1st rib (rib) ), 296b Second rib (rib), J2 ... Motor axis, J4 ... Intermediate axis, J5 ... Differential axis, L1 ... First segment, L2 ... Second segment, L3 ... Third segment, O ... Oil, P: Oil reservoir

Claims

A motor having a shaft that rotates about a motor axis;
A reduction gear having an intermediate gear connected to the shaft and rotating about an intermediate shaft;
A differential gear having a ring gear connected to the reduction gear and rotating about a differential shaft;
A housing provided with a gear chamber for accommodating the reduction gear and the differential device;
And oil accumulated in a lower region of the gear chamber,
The motor shaft, the intermediate shaft and the differential shaft extend horizontally in parallel with one another,
The intermediate shaft and the differential shaft are located below the motor shaft,
At least a portion of the ring gear is immersed in the oil collected in the lower region of the gear chamber,
The housing has a first oil receiver located below the intermediate gear and extending along a tip circle of the intermediate gear.
In the first oil receiving portion, the oil scraped up by the rotation of the ring gear from the lower region of the gear chamber is accumulated,
The oil accumulated in the first oil receiving portion is scooped up by the intermediate gear.
Motor unit.
The housing has a first member and a second member arranged along the axial direction and surrounding the gear chamber,
The first member and the second member each have an opposing surface opposed to each other in the axial direction, and a rib projecting along the axial direction from the opposing surface,
The rib of the first member and the rib of the second member are abutted against each other to constitute the first oil receiver.
The motor unit according to claim 1.
The first oil receiver overlaps with the ring gear in the axial direction.
A motor unit according to claim 1 or 2.
The housing has a first oil guiding portion located immediately above the first oil receiving portion and extending in the vertical direction.
The first oil guiding portion overlaps the ring gear in the axial direction.
The motor unit according to any one of claims 1 to 3.
The shaft is a hollow shaft,
The housing is
A second oil receiver located above the intermediate shaft and the differential shaft in the vertical direction and located between the intermediate shaft and the differential shaft in the horizontal direction;
An oil introduction passage connecting the second oil receiving portion and the inside of the shaft;
In the second oil receiving portion, the oil scraped up by the rotation of the ring gear from the lower region of the gear chamber and the oil scraped out by the rotation of the intermediate gear from the first oil receiving portion At least one will accumulate,
The motor unit according to any one of claims 1 to 4.
The shaft is a hollow shaft,
The housing is
And a second oil receiver located between the intermediate shaft and the differential shaft in the horizontal direction above the intermediate shaft and the differential shaft,
The second oil receiver at least partially surrounds a portion of the outer periphery of the shaft,
The shaft is provided with a through hole through which the oil accumulated in the second oil receiving portion is introduced into the shaft.
In the second oil receiving portion, the oil scraped up by the rotation of the ring gear from the lower region of the gear chamber and the oil scraped out by the rotation of the intermediate gear from the first oil receiving portion At least one will accumulate,
The motor unit according to any one of claims 1 to 4.
The housing has a second oil guiding portion which is located on the differential shaft side in the horizontal direction with respect to the intermediate gear and extends in the vertical direction along a tip circle of the intermediate gear.
The second oil receiver has a bottom and a side wall extending upward from the bottom.
The side wall portion includes a first wall portion facing the second oil guiding portion in the horizontal direction,
The upper end of the second oil guiding portion extends upward from the first wall portion,
A motor unit according to claim 5 or 6.
The second oil receiving portion and the shaft are horizontally aligned;
A motor unit according to any one of claims 5 to 7.
The first oil receiving portion is provided in a range of 120 ° or more and 140 ° or less centering on the intermediate shaft on the lower side of the intermediate gear when viewed from the axial direction of the motor shaft.
A motor unit according to any one of claims 1 to 8.
The intermediate gear has a large diameter gear and a small diameter gear aligned along an axial direction,
The large diameter gear meshes with a pinion gear fixed to the shaft,
The small diameter gear meshes with the ring gear,
The first oil receiving portion extends along a tip circle of the large diameter gear.
The motor unit according to any one of claims 1 to 9.
Seen from the axial direction of the motor shaft,
A line segment virtually connecting the motor shaft and the intermediate shaft is a first line segment,
A line segment virtually connecting the intermediate axis and the differential axis is a second line segment,
When a line segment virtually connecting the motor shaft and the differential axis is a third line segment:
The first line segment extends substantially in the vertical direction,
The second line segment extends substantially horizontally.
The motor unit according to any one of claims 1 to 10.