WO2019202947A1

WO2019202947A1 - Motor unit

Info

Publication number: WO2019202947A1
Application number: PCT/JP2019/013733
Authority: WO
Inventors: 山口　康夫; 久嗣藤原; 中村　圭吾; 隆宏檜皮
Original assignee: 日本電産株式会社
Priority date: 2018-04-20
Filing date: 2019-03-28
Publication date: 2019-10-24
Also published as: CN111989234B; CN111989234A

Abstract

One aspect of this motor unit is a motor unit that rotates a wheel axle of a vehicle, the motor unit comprising: a motor having a motor shaft that rotates about a motor axle; a speed reducer connected to the motor shaft; a differential device that is connected to the speed reducer and that rotates the wheel axle about a differential axle; a housing having a motor-accommodating part that accommodates the motor, and a gear-accommodating part which accommodates the speed reducer and the differential device and inside of which oil is accommodated; and a storage part which opens vertically upward inside the gear-accommodating part, and which can store oil. The differential axle aligns with the motor axle. The motor shaft is a hollow shaft that opens at both sides in an axial direction. The wheel axle is passed through the interior of the motor shaft. One axial end of the motor shaft protrudes into the gear-accommodating part. Within the opening in one axial side of the motor shaft, a diametral gap between the motor shaft and the wheel axle is at least partially positioned inside the storage part.

Description

Motor unit

The present invention relates to a motor unit.

An electric drive device for driving a vehicle is known. For example, Patent Document 1 describes a configuration in which an output shaft passes through a hollow shaft of a motor.

Japanese publication: JP 2017-534032 A

In the above configuration, it is conceivable to cool the motor by supplying oil into the hollow shaft. However, since the output shaft is passed through the hollow shaft, it is necessary to supply oil to the gap between the hollow shaft and the output shaft, and it is difficult to supply oil to the inside of the hollow shaft. Therefore, there is a problem that it is difficult to secure a sufficient amount of oil to be supplied to the motor.

In view of the above circumstances, an object of the present invention is to provide a motor unit having a structure capable of improving the amount of oil supplied into a hollow motor shaft through which an axle is passed.

One aspect of the motor unit of the present invention is a motor unit that rotates an axle of a vehicle, the motor having a motor shaft that rotates about the motor shaft, a speed reduction device connected to the motor shaft, and the speed reduction A differential device that is connected to a device and rotates the axle around a differential shaft, a motor housing portion that houses the motor, and a gear housing that houses the speed reducer and the differential device and contains oil therein And a storage portion that opens upward in the vertical direction inside the gear housing portion and can store oil. The differential axis coincides with the motor axis. The motor shaft is a hollow shaft that opens on both sides in the axial direction. The axle is passed through the motor shaft. One end of the motor shaft in the axial direction protrudes into the gear housing portion. At least a part of the radial clearance between the motor shaft and the axle in the opening on one side in the axial direction of the motor shaft is located inside the storage portion.

According to one aspect of the present invention, in the motor unit, the amount of oil supplied into the hollow motor shaft through which the axle is passed can be improved.

FIG. 1 is a diagram schematically showing a power train including the motor unit of the present embodiment. FIG. 2 is a diagram schematically illustrating a power train including the motor unit of the present embodiment. FIG. 3 is a diagram schematically illustrating a power train including the motor unit of the present embodiment. FIG. 4 is a perspective view showing the motor unit of the present embodiment. FIG. 5 is a view of the motor unit of the present embodiment as viewed from the right side. FIG. 6 is a view of a part of the motor unit of this embodiment as viewed from above. FIG. 7 is a sectional view showing a part of the motor unit of the present embodiment, and is a sectional view taken along the line VII-VII in FIG. FIG. 8 is a sectional view showing a part of the motor unit of the present embodiment, and is a sectional view taken along the line VIII-VIII in FIG.

In the following description, the vertical direction is defined and described based on the positional relationship when the motor unit 10 of the present embodiment shown in each drawing is mounted on a vehicle located on a horizontal road surface. In the drawings, an XYZ coordinate system is appropriately shown as a three-dimensional orthogonal coordinate system. In the XYZ coordinate system, the Z-axis direction is the vertical direction. The + Z side is the upper side in the vertical direction, and the −Z side is the lower side in the vertical direction. In the following description, the upper side in the vertical direction is simply referred to as “upper side”, and the lower side in the vertical direction is simply referred to as “lower side”. The X-axis direction is a direction orthogonal to the Z-axis direction and is the front-rear direction of the vehicle on which the motor unit 10 is mounted. In the present embodiment, the + X side is the front side of the vehicle, and the −X side is the rear side 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 left-right direction (vehicle width direction) of the vehicle. In the present embodiment, the + Y side is the left side of the vehicle, and the -Y side is the right side of the vehicle. In the present embodiment, the right side corresponds to one side in the axial direction.

Note that the positional relationship in the front-rear direction is not limited to the positional relationship of the present embodiment, and the + X side may be the rear side of the vehicle, and the −X side may be the front side of the vehicle. In this case, the + Y side is the right side of the vehicle, and the -Y side is the left side of the vehicle.

The motor shaft J1 shown as appropriate in each drawing extends in the Y-axis direction, that is, the left-right direction of the vehicle. In the following description, unless otherwise specified, the direction parallel to the motor shaft J1 is simply referred to as “axial direction”, the radial direction around the motor shaft J1 is simply referred to as “radial direction”, and the motor shaft J1 is The central circumferential direction, that is, the axis around the motor shaft J1 is simply referred to as “circumferential direction”. In the present specification, the “parallel direction” includes a substantially parallel direction, and the “perpendicular direction” includes a substantially orthogonal direction.

As shown in FIGS. 1 to 3, the motor unit 10 of the present embodiment is provided in the power train 1. The power train 1 includes a motor unit 10, an engine 2, and a battery 3. The powertrain 1 is mounted on a vehicle that uses the motor unit 10 and the engine 2 as power sources, such as a hybrid vehicle (HEV) and a plug-in hybrid vehicle (PHV).

Engine 2 is an internal combustion engine that burns fuel such as gasoline and light oil. The engine 2 is, for example, a gasoline engine or a diesel engine. The engine 2 of the present embodiment is a so-called horizontal engine in which the direction of the crankshaft 2a coincides with the left-right direction of the vehicle, that is, the axial direction. The battery 3 supplies power to the motor unit 10.

The motor unit 10 of this embodiment is mounted on a vehicle including the engine 2 and rotates the axle AX of the vehicle. The motor unit 10 includes a housing 11, a motor 20 having a motor shaft 22 that rotates about a motor shaft J <b> 1, a speed reduction device 30, a differential device 50, a generator 40, and a clutch mechanism 60.

The housing 11 accommodates the motor 20, the reduction gear 30, the differential device 50, the generator 40 and the clutch mechanism 60. As shown in FIGS. 4 to 6, the housing 11 includes a motor housing portion 12 and a gear housing portion 13. The motor housing portion 12 is a portion that houses the motor 20. The motor housing portion 12 has a cylindrical shape that extends in the axial direction about the motor shaft J1. The gear housing portion 13 is a portion that houses the reduction gear device 30, the generator 40, and the differential device 50. The gear housing part 13 is located on the right side of the motor housing part 12. The gear housing part 13 projects forward from the motor housing part 12.

As shown in FIG. 7, oil O is accommodated in the housing 11. More specifically, oil O is accommodated in the motor accommodating portion 12 and the gear accommodating portion 13, respectively. In the lower region of the motor accommodating portion 12, an oil reservoir OR1 in which the oil O is accumulated is provided. An oil reservoir OR2 in which oil O is accumulated is provided in the lower region of the gear housing portion 13. In FIG. 7, the oil level of the oil sump OR1 in the motor accommodating part 12 is located above the oil level of the oil sump OR2 in the gear accommodating part 13, for example. For example, the oil level of the oil reservoir OR1 is positioned below the rotor 21 described later when the motor 20 is driven. Thereby, it can suppress that rotation of the rotor 21 is inhibited by the oil O of the oil reservoir OR1. In FIG. 7, the illustration of the engine shaft J2, the generator 40, and the clutch mechanism 60 is omitted.

The housing 11 further includes a partition wall portion 14 and a bearing holding wall portion 15. The partition wall part 14 partitions the motor housing part 12 and the gear housing part 13. The partition wall portion 14 has a hole portion 14a that penetrates the partition wall portion 14 in the axial direction. The axle 14 and the motor shaft 22 are passed through the hole 14a. A bearing 27b that rotatably supports the motor shaft 22 is fitted and held in the hole 14a.

The partition wall portion 14 has an oil passage 14 b that connects the inside of the motor housing portion 12 and the inside of the gear housing portion 13. The oil passage 14b penetrates the partition wall portion 14 in the axial direction. In the present embodiment, the oil passage 14b extends linearly along the axial direction. The oil passage 14b is located below the hole 14a. The oil O in the motor housing portion 12 can move into the gear housing portion 13 through the oil passage 14b.

The bearing holding wall portion 15 extends radially inward from the inner peripheral surface of the motor housing portion 12. The bearing holding wall portion 15 is located on the left side of a stator 24 described later. The interior of the motor housing portion 12 is partitioned in the axial direction by the bearing holding wall portion 15. The bearing holding wall portion 15 has a hole portion 15a penetrating the bearing holding wall portion 15 in the axial direction. The axle AX and the motor shaft 22 are passed through the hole 15a. A bearing 27a that rotatably supports the motor shaft 22 is fitted and held in the hole 15a. The bearing holding wall portion 15 has a through portion 15b at the lower end. The through portion 15 b connects the portions of the interior of the motor housing portion 12 that are partitioned in the axial direction by the bearing holding wall portion 15. Since the penetrating portion 15 b is provided, the oil reservoir OR <b> 1 is provided across the axially opposite sides of the bearing holding wall portion 15 in the motor housing portion 12.

The motor 20 outputs torque that rotates the axle AX. The torque of the motor 20 is transmitted to the axle AX via the speed reduction device 30 and the differential device 50. In the present embodiment, the motor 20 also has a function as a generator. For example, the motor 20 functions as a generator during regeneration.

The motor 20 has a rotor 21 and a stator 24. The rotor 21 has a motor shaft 22 and a rotor body 23. The rotor body 23 is fixed to the outer peripheral surface of the motor shaft 22. Although illustration is omitted, the rotor main body 23 includes a rotor core and a rotor magnet.

The motor shaft 22 extends in the axial direction around the motor shaft J1. The motor shaft 22 is a hollow shaft that opens on both sides in the axial direction. As shown in FIG. 8, the outer shape of the motor shaft 22 viewed along the axial direction is a circular shape centered on the motor shaft J1. As shown in FIG. 7, the motor shaft 22 is supported by

bearings

27a and 27b so as to be rotatable around the motor axis J1. The

bearings

27a and 27b are ball bearings, for example. The bearing 27 a is held by the bearing holding wall 15 and supports a portion of the motor shaft 22 on the left side of the rotor body 23. The bearing 27 b is held by the partition wall portion 14 and supports a portion of the motor shaft 22 on the right side of the rotor body 23.

The right end of the motor shaft 22 protrudes into the gear housing 13 through the hole 14a. A speed reducer 30 is connected to the right end of the motor shaft 22. The left end of the motor shaft 22 projects through the hole 15a to the left side of the bearing holding wall 15 in the motor housing 12.

The motor shaft 22 has shaft through

holes

22 a, 22 b, 22 c, and 22 d that connect the inside of the motor shaft 22 and the outer peripheral surface of the motor shaft 22. In the present embodiment, a plurality of shaft through

holes

22a, 22b, 22c, and 22d are provided along the circumferential direction. The shaft through holes 22 a and 22 b are provided in a portion of the motor shaft 22 located between the partition wall portion 14 and the bearing holding wall portion 15 in the axial direction. The shaft through hole 22 a is provided in a portion of the motor shaft 22 on the left side of the rotor body 23. The shaft through hole 22 b is provided in a portion on the right side of the rotor body 23 in the motor shaft 22. The shaft through holes 22a and 22b are opposed to a coil 26, which will be described later, via a gap in the radial direction.

The shaft through hole 22c is provided in a portion of the motor shaft 22 located in the hole 15a. The shaft through hole 22c opens into the hole 15a. The shaft through hole 22d is provided in a portion of the motor shaft 22 located in the hole 14a. The shaft through hole 22d opens inside the hole 14a.

The stator 24 faces the rotor 21 in the radial direction through a gap. The stator 24 is located on the radially outer side of the rotor 21. The stator 24 includes a stator core 25, an insulator (not shown), and a plurality of coils 26. The plurality of coils 26 are attached to the stator core 25 via an insulator (not shown). The stator 24 is fixed inside the motor housing portion 12. The lower end of the stator 24 is immersed in the oil reservoir OR1.

The reduction gear 30 reduces the rotational speed of the motor 20 and increases the torque output from the motor 20 according to the reduction ratio. The reduction gear 30 transmits the torque output from the motor 20 to the differential device 50. The reduction gear device 30 includes a motor drive gear 31, a counter gear 32, a drive gear 33, and a counter shaft 34. The motor drive gear 31 is fixed to the motor shaft 22. Thereby, the reduction gear device 30 is connected to the motor shaft 22. In the present embodiment, the motor drive gear 31 is fixed to the right end of the motor shaft 22.

The counter gear 32 rotates around a counter shaft J3 parallel to the motor shaft J1. The counter shaft J3 is located on the radially outer side of the motor shaft J1. In the present embodiment, the counter shaft J3 is located above the motor shaft J1. As shown in FIG. 5, the counter shaft J3 is located on the front side of the motor shaft J1.

As shown in FIG. 7, the counter gear 32 meshes with the motor drive gear 31. The counter gear 32 is located above the motor drive gear 31. The drive gear 33 is located on the right side of the counter gear 32. The drive gear 33 rotates around the counter shaft J3 together with the counter gear 32. The outer diameter of the drive gear 33 is smaller than the outer diameter of the counter gear 32.

The counter shaft 34 extends in the axial direction around the counter axis J3. The counter shaft 34 is supported by the

bearings

35a and 35b so as to be rotatable around the counter axis J3. The

bearings

35a and 35b are ball bearings, for example. The

bearings

35 a and 35 b are respectively held on the wall portions on both sides in the axial direction of the gear housing portion 13. A counter gear 32 and a drive gear 33 are fixed to the outer peripheral surface of the counter shaft 34. Therefore, the counter gear 32 and the drive gear 33 are connected via the counter shaft 34.

The torque output from the motor shaft 22 of the motor 20 is transmitted to the differential device 50 through the motor drive gear 31, the counter gear 32, and the drive gear 33 in this order. The gear ratio of each gear, the number of gears, and the like can be variously changed according to the required reduction ratio. In the present embodiment, the speed reduction device 30 is a parallel shaft gear type speed reducer in which the shaft cores of the respective gears are arranged in parallel.

The differential device 50 is connected to the speed reducer 30. The differential device 50 is a device for transmitting torque output from the motor 20 to the wheels H of the vehicle. The differential device 50 transmits torque to the axle AX and rotates the axle AX around the differential axis. The differential shaft of the differential device 50 coincides with the motor shaft J1. A pair of axles AX are provided with the differential device 50 sandwiched in the axial direction. The pair of axles AX extends in the axial direction. The axle AX has a columnar shape centered on the motor shaft J1. The left axle AX of the pair of axles AX is passed through the inside of the motor shaft 22 that is a hollow shaft. Therefore, compared with the case where the motor shaft J1 and the differential shaft are not coaxially arranged, the motor unit 10 can be easily downsized in the radial direction. Therefore, according to this embodiment, the motor unit 10 including the generator 40 connected to the engine 2 can be downsized. The left axle AX of the pair of axles AX penetrates the motor shaft 22 in the axial direction.

In each of the pair of axles AX, the axial end opposite to the side connected to the differential device 50 out of the axial end of the axle AX protrudes from the housing 11 in the axial direction. As shown in FIGS. 1 to 3, in each of the pair of axles AX, wheels H are respectively attached to axial ends protruding from the housing 11 of the axles AX.

The differential device 50 includes a ring gear 51, a pair of pinion gears (not shown), a pinion shaft (not shown), and a pair of side gears (not shown). In the present embodiment, the ring gear 51 is located on the right side of the motor shaft 22 and the motor drive gear 31. The ring gear 51 rotates around the differential shaft (motor shaft J1). Ring gear 51 meshes with drive gear 33. Thereby, the torque output from the motor 20 is transmitted to the ring gear 51 via the reduction gear 30. As shown in FIG. 7, the lower end portion of the ring gear 51 is immersed in the oil reservoir OR <b> 2 in the gear housing portion 13. Thereby, the oil O is scraped up when the ring gear 51 rotates. The oil O that has been scooped up becomes mist and is sprayed inside the gear housing 13. Thereby, oil O can be supplied to each part arrange | positioned inside the gear accommodating part 13. FIG.

The generator 40 shown in FIGS. 1 to 3 generates power by the power of the engine 2. The electric power generated by the generator 40 is charged in the battery 3 that supplies electric power to the motor 20 or is supplied to the stator 24 of the motor 20 without going through the battery 3. Thus, the generator 40 can supply electric power to the motor 20. In the present embodiment, the generator 40 also has a function as a motor. For example, the generator 40 functions as a motor (starter) when starting the engine 2.

As shown in FIG. 6, in this embodiment, the generator 40 is connected to the reduction gear device 30 via the clutch mechanism 60. Thus, the power of the engine 2 is transmitted to the differential device 50 via the generator 40, the clutch mechanism 60, and the speed reduction device 30. The generator 40 is located in front of the speed reduction device 30 and the differential device 50. As shown in FIGS. 1 to 3, the generator 40 includes a rotor 41 and a stator 44. The rotor 41 includes an engine drive shaft 42 that rotates about an engine axis J2 that is parallel to the motor axis J1, and a rotor body 43.

The engine shaft J2 is located on the outer side in the radial direction of the motor shaft J1. As shown in FIG. 5, in this embodiment, the engine shaft J2 is located in front of the motor shaft J1 and the counter shaft J3. The motor shaft J1 and the engine shaft J2 are located at substantially the same position in the vertical direction. In the present embodiment, the engine shaft J2 is positioned slightly above the motor shaft J1. As shown in FIGS. 1 to 3, the rotor main body 43 is fixed to the outer peripheral surface of the engine drive shaft 42. Although illustration is omitted, the rotor main body 43 has a rotor core and a rotor magnet.

The engine drive shaft 42 has a cylindrical shape extending in the axial direction around the engine axis J2. As shown in FIG. 4, the right end of the engine drive shaft 42 protrudes outside the housing 11. As shown in FIGS. 1 to 3, the right end of the engine drive shaft 42 is connected to the engine 2 via a damper 2b. Thereby, the motor unit 10 is connected to the engine 2. The damper 2b functions as a torque limiter. The damper 2b reduces vibrations caused by sudden torque fluctuations such as when the engine 2 is suddenly accelerated by the engine 2. The engine drive shaft 42 is rotated around the engine axis J2 by the engine 2. That is, the rotor 41 is rotated by the power of the engine 2. Thereby, a voltage is generated in the stator 44 by electromagnetic induction, and the generator 40 can generate power.

Thus, according to this embodiment, the power of the engine 2 is transmitted to the engine drive shaft 42 of the generator 40 without a gear. Therefore, the number of shafts and gears necessary for transmitting power from the engine 2 to the axle AX can be reduced. Therefore, the motor unit 10 can be further reduced in size and weight.

Although illustration is omitted, the engine drive shaft 42 has an oil passage extending in the axial direction therein. Although not shown, the engine drive shaft 42 has a shaft through hole that connects an oil passage provided inside and the outer peripheral surface of the engine drive shaft 42. A plurality of shaft through holes of the engine drive shaft 42 are provided, for example, similarly to the shaft through

holes

22a, 22b, 22c, and 22d of the motor shaft 22.

The stator 44 faces the rotor 41 in the radial direction of the engine shaft J2 through a gap. The stator 44 is located outside the rotor 41 in the radial direction of the engine shaft J2. The stator 24 includes a stator core 45, an insulator (not shown), and a plurality of coils 46. The plurality of coils 46 are attached to the stator core 45 via an insulator (not shown). The stator 44 is fixed inside the gear housing portion 13.

The clutch mechanism 60 switches between disconnection and connection between the generator 40 and the reduction gear 30. The clutch mechanism 60 of the present embodiment is referred to as a rotation synchronization device or a synchromesh mechanism, for example. The clutch mechanism 60 includes a clutch shaft 61, a first flange portion 62, a second flange portion 63, an engine drive gear 64, a movable portion 65, and a synchronizer ring (not shown). Further, as shown in FIGS. 4 to 6, the clutch mechanism 60 has a drive unit 66. The drive part 66 is attached to the upper wall part of the gear housing part 13. For example, the drive unit 66 is driven by power supplied from the battery 3.

As shown in FIGS. 1 to 3, the clutch shaft 61 is located on the left side of the engine drive shaft 42 and extends in the axial direction about the engine axis J2. Although illustration is omitted, the clutch shaft 61 has an oil passage extending in the axial direction therein. The oil passage inside the clutch shaft 61 is connected to the oil passage inside the engine drive shaft 42 when the clutch shaft 61 and the engine drive shaft 42 are connected. Although not shown, the clutch shaft 61 has a shaft through hole that connects an oil passage provided inside and the outer peripheral surface of the clutch shaft 61. A plurality of shaft through holes of the clutch shaft 61 are provided in the same manner as the shaft through

holes

22a, 22b, 22c, 22d of the motor shaft 22, for example.

The first flange portion 62 extends outward from the left end portion of the engine drive shaft 42 in the radial direction of the engine shaft J2. The second flange portion 63 extends outward from the right end portion of the clutch shaft 61 in the radial direction of the engine shaft J2. Although not shown, external splines are provided on the outer peripheral surface of the first flange portion 62 and the outer peripheral surface of the second flange portion 63, respectively.

The engine drive gear 64 is fixed to the left end of the clutch shaft 61. The engine drive gear 64 rotates around the engine axis J2 together with the clutch shaft 61. When the clutch mechanism 60 is connected to the generator 40, the engine drive gear 64 is rotated by the engine 2 via the generator 40. The engine drive gear 64 meshes with the counter gear 32. Thereby, the generator 40 is connected to the reduction gear 30.

The movable part 65 is moved in the axial direction by the drive part 66. Although illustration is omitted, the movable portion 65 has a cylindrical shape surrounding the engine shaft J2. Although illustration is omitted, an internal spline is provided on the inner peripheral surface of the movable portion 65. The movable portion 65 surrounds the outside of the second flange portion 63 in the radial direction of the engine shaft J2, and the internal tooth spline meshes with the external tooth spline of the second flange portion 63. Accordingly, the movable portion 65 rotates together with the clutch shaft 61, the second flange portion 63, and the engine drive gear 64.

When the movable part 65 is moved in the axial direction by the drive part 66, the disconnection and connection between the clutch mechanism 60 and the generator 40 are switched. 1 and 2 show a state in which the generator 40 and the speed reduction device 30 are disconnected, and FIG. 3 shows a state in which the power generator 40 and the speed reduction device 30 are connected. As shown in FIG. 3, when the movable portion 65 moves to the right from the state shown in FIGS. 1 and 2, the internal splines of the movable portion 65 mesh with the external splines of the first flange portion 62. Accordingly, the first flange portion 62 and the second flange portion 63 are connected via the movable portion 65, and the engine drive shaft 42 and the clutch shaft 61 are connected. Therefore, the generator 40 and the reduction gear device 30 are connected via the clutch mechanism 60.

On the other hand, as shown in FIGS. 1 and 2, when the movable portion 65 moves to the left from the state shown in FIG. 2, the internal tooth spline of the movable portion 65 is disengaged from the external tooth spline of the first flange portion 62. The connection between the portion 62 and the second flange portion 63 is disconnected. Therefore, the connection between the engine drive shaft 42 and the clutch shaft 61 is disconnected, and the connection between the generator 40 and the reduction gear 30 is disconnected.

As described above, the clutch mechanism 60 can switch between disconnection and connection between the generator 40 and the speed reduction device 30 by moving the movable portion 65 in the axial direction by the drive portion 66. In this embodiment, the power of the engine 2 is transmitted to the differential device 50 via the generator 40, the clutch mechanism 60, and the speed reducer 30 when the power generator 40 and the speed reducer 30 are connected by the clutch mechanism 60. Is done. On the other hand, when the clutch mechanism 60 is disconnected from the generator 40, the power of the engine 2 is not transmitted to the differential device 50.

A synchronizer ring (not shown) is fixed to the movable portion 65. The synchronizer ring moves in the axial direction together with the movable portion 65. In the synchronizer ring, when the movable portion 65 moves to the right side to connect the generator 40 and the speed reducer 30, the internal tooth spline of the movable portion 65 is engaged with the external tooth spline of the first flange portion 62. And a contact surface that contacts the first flange portion 62. Thereby, the synchronizer ring and the first flange portion 62 are synchronously rotated by the frictional force between the synchronizer ring and the first flange portion 62, and the engine drive shaft 42 and the clutch shaft 61 are synchronously rotated. Therefore, the engine drive shaft 42 and the clutch shaft 61 can be connected via the movable portion 65 in a state where the engine drive shaft 42 and the clutch shaft 61 are synchronously rotated. Therefore, when the generator 40 and the reduction gear 30 are connected by the clutch mechanism 60, it is possible to suppress a large impact from being applied to the engine drive shaft 42 and the clutch shaft 61.

As shown in FIG. 7, the motor unit 10 further includes a storage unit 70. The storage part 70 is located inside the gear housing part 13. The reservoir 70 opens to the upper side and can store the oil O. In the present embodiment, the storage unit 70 has, for example, a rectangular parallelepiped box shape that opens upward. The oil O inside the gear housing part 13 is stored inside the storage part 70. Here, in the present embodiment, as described above, the lower end of the ring gear 51 is immersed in the oil reservoir OR2, so that the oil O of the oil reservoir OR2 is scraped up by the ring gear 51. Thereby, the oil O scraped up by the ring gear 51 is sprayed into the gear housing portion 13 and is easily collected in the storage portion 70. Therefore, the oil O in the gear housing part 13 can be efficiently collected in the storage part 70. A part of the oil O that falls after being supplied to the generator 40 by an oil pump (not shown) to be described later is also stored in the storage unit 70.

The reservoir 70 covers the right end of the motor shaft 22. That is, the right end portion of the motor shaft 22 is located inside the storage portion 70. Accordingly, at least a part of the radial gap between the motor shaft 22 and the axle AX in the opening on the right side of the motor shaft 22 is located inside the storage unit 70. Therefore, when the oil O accumulates in the reservoir 70 and the oil level of the oil O in the reservoir 70 reaches the radial gap between the motor shaft 22 and the axle AX, the oil O in the reservoir 70 is caused by negative pressure. The air is sucked into the radial gap between the motor shaft 22 and the axle AX. Thereby, the oil O etc. which were spread | dispersed in the gear accommodating part 13 by the ring gear 51 can be collected efficiently, and it can supply to the inside of the motor shaft 22. FIG. Therefore, according to the present embodiment, the supply amount of the oil O into the motor shaft 22 can be improved even when the axle AX is passed through the hollow motor shaft 22. Thereby, the motor 20 can be cooled suitably.

In the present embodiment, the radial clearance between the motor shaft 22 and the axle AX in the opening on the right side of the motor shaft 22 is entirely located inside the storage unit 70. Therefore, the oil O stored in the storage unit 70 is more easily sucked into the motor shaft 22. The oil O sucked into the motor shaft 22 flows to the left side through a radial gap between the motor shaft 22 and the axle AX.

Here, according to the present embodiment, the motor shaft 22 has shaft through

holes

22 a, 22 b, 22 c, and 22 d that connect the inside of the motor shaft 22 and the outer peripheral surface of the motor shaft 22. Therefore, the oil O supplied into the motor shaft 22 is ejected to the outside in the radial direction of the motor shaft 22 through the shaft through

holes

22a, 22b, 22c, and 22d. Thereby, the oil O can be supplied to the stator 24 and the

bearings

27a and 27b. Therefore, the stator 24 can be suitably cooled by the oil O, and lubricating oil can be suitably supplied to the

bearings

27a and 27b. In the present embodiment, the oil O ejected from the shaft through holes 22 a and 22 b is supplied to the coil 26. The oil O ejected from the shaft through

holes

22c and 22d is supplied to the

bearings

27a and 27b.

The oil O ejected from the shaft through-

holes

22a, 22b, 22c, and 22d is supplied to each part and then falls into the oil reservoir OR1 of the motor housing part 12. Of the oil O supplied into the motor shaft 22, the oil O that has not been ejected from the shaft through

holes

22 a, 22 b, 22 c, 22 d is discharged from the opening on the left side of the motor shaft 22. The oil O discharged from the opening on the left side of the motor shaft 22 falls to a portion on the left side of the bearing holding wall portion 15 in the oil reservoir OR1 of the motor housing portion 12. At least a portion of the oil O stored in the motor housing portion 12, that is, at least a portion of the oil O in the oil reservoir OR1 flows into the gear housing portion 13 through the oil passage 14b. Thereby, the oil O supplied to the motor 20 from the oil reservoir OR <b> 2 in the gear housing portion 13 can be returned to the gear housing portion 13.

In this embodiment, the motor drive gear 31 is accommodated in the storage unit 70. In the present embodiment, the upper end portion of the motor drive gear 31 protrudes upward from the opening of the storage portion 70, for example. As shown in FIG. 7 and FIG. 8, in the present embodiment, the storage unit 70 includes a bottom wall portion 71, axial

side wall portions

72 and 73, and front and rear direction

side wall portions

74 and 75. As shown in FIG. 7, the bottom wall portion 71 extends to the right from a portion of the partition wall portion 14 above the oil passage 14b. The bottom wall portion 71 is located above the oil level of the oil reservoir OR2 in the gear housing portion 13.

The axial

side wall portions

72 and 73 extend upward from the end portions on both axial sides of the bottom wall portion 71. The axial side wall 72 extends upward from the right end of the partition wall 14. The axial side wall 72 has a hole 72 a that passes through the axial side wall 72 in the axial direction. Although not shown, the hole 72a has a circular shape centered on the motor shaft J1. The axle shaft AX is passed through the hole 72a.

The axial side wall 73 extends upward from the left end of the bottom wall 71. In the present embodiment, the axial side wall 73 is a portion of the partition wall 14 that overlaps with the axial side wall 72 when viewed in the axial direction. That is, a part of the wall part that constitutes the storage part 70 in this embodiment is a part of the partition wall part 14. Thus, since the storage part 70 can be made using a part of the partition wall part 14, the preparation of the storage part 70 is easy. The axial side wall 73 is provided with a hole 14a.

As shown in FIG. 8, the front and rear

side wall portions

74 and 75 extend upward from the end portions on both sides in the front and rear direction of the bottom wall portion 71. The front-rear direction side wall 74 extends upward from the front end of the bottom wall 71. The front-rear direction side wall portion 74 connects the end portions on the front side of the axial

side wall portions

72 and 73. The front-rear direction side wall 75 extends upward from the rear end of the bottom wall 71. The front-rear direction side wall 75 connects the end portions on the rear side of the

axial side walls

72, 73.

The bottom wall 71, the axial side wall 72, and the front and

rear side walls

74, 75 are each plate-shaped. The bottom wall portion 71, the axial side wall portion 72, and the front and rear direction

side wall portions

74 and 75 are part of the same single member. In this embodiment, the storage part 70 can be easily made by fixing the single member which has the bottom wall part 71, the axial direction side wall part 72, and the front-back direction

side wall parts

74 and 75 to the partition wall part 14. FIG. it can.

The motor unit 10 further includes an oil pump (not shown). The oil pump is a mechanical pump attached to the engine drive shaft 42, for example. The oil pump sucks up the oil O from the oil reservoir OR2 in the gear housing 13 and supplies the oil O to an oil passage (not shown) provided in the engine drive shaft 42 and in the clutch shaft 61. Thereby, the rotor 41 of the generator 40 can be cooled. The oil O supplied to the oil passage inside the engine drive shaft 42 is ejected to the outside of the engine drive shaft 42 through a shaft through hole that connects the oil passage inside the engine drive shaft 42 and the outer peripheral surface of the engine drive shaft 42. The The jetted oil O is supplied to a bearing (not shown) that supports the stator 44 and the engine drive shaft 42 of the generator 40. Thereby, the stator 44 can be cooled, and lubricating oil can be supplied to a bearing (not shown). The oil O supplied to the stator 44 and a bearing (not shown) falls to the oil reservoir OR2 in the gear housing portion 13.

The oil pump supplies oil O to the motor 20 as well. The oil pump supplies oil O from the upper side to the stator 24 via an oil passage (not shown) provided in the upper wall portion of the motor housing portion 12. Thereby, the stator 24 can be cooled more. The oil O supplied to the motor 20 by the oil pump falls into the oil reservoir OR1 in the motor housing portion 12.

In this embodiment, the oil pump is driven by the power of the engine 2. Therefore, the oil pump can be driven freely if the engine 2 is driven even when the clutch mechanism 60 is disconnected from the generator 40. The oil pump may be an electric oil pump.

The power train 1 further includes an inverter (not shown). The inverter (not shown) is electrically connected to the stator 24 of the motor 20 and the stator 44 of the generator 40. The power supplied to the

stators

24 and 44 can be adjusted by the inverter. The inverter is housed in, for example, an inverter case that houses the inverter. The inverter case is fixed to the outer surface of the housing 11. The inverter is controlled by an electronic control device (not shown).

The vehicle on which the motor unit 10 is mounted has three types of travel modes, EV mode, series mode, and parallel mode. These travel modes are alternatively selected by an electronic control unit (not shown) according to the vehicle state, the travel state, the driver's requested output, and the like. FIG. 1 shows a power train 1 in the EV mode. FIG. 2 shows the power train 1 in the series mode. FIG. 3 shows the power train 1 in the parallel mode.

As shown in FIG. 1, the EV mode is a traveling mode in which the vehicle is driven only by the motor 20 using the charging power of the battery 3 while the engine 2 and the generator 40 are stopped. The EV mode is selected when the traveling load is low or the battery charge level is high. In the EV mode, the clutch mechanism 60 is in a state where the generator 40 and the speed reduction device 30 are disconnected. When the rotor 21 is rotated by supplying electric power from the battery 3, the rotation of the motor shaft 22 is transmitted in the order of the motor drive gear 31, the counter gear 32, the counter shaft 34, the drive gear 33, the ring gear 51, and the axle AX. . As a result, the axle 20 and the wheels H can be rotated by the motor 20, and the vehicle can be driven.

As shown in FIG. 2, the series mode is a traveling mode in which the generator 2 is driven by the engine 2 to generate electric power, and the vehicle is driven by the motor 20 using the electric power. The electric power generated by the generator 40 in the series mode is supplied to both the battery 3 and the motor 20, for example. Thereby, the battery 3 can be charged. The series mode is selected when the traveling load is medium or when the battery charge level is low. In the series mode, the clutch mechanism 60 is in a state where the generator 40 and the speed reduction device 30 are disconnected. In the series mode, rotation transmission from the motor 20 to the axle AX is the same as in the EV mode.

In this embodiment, since the clutch mechanism 60 is provided, the power of the motor 20 can be prevented from being transmitted to the generator 40 and the engine 2 in the EV mode and the series mode described above. Therefore, an increase in the load applied to the motor 20 can be suppressed, and power generation can be suitably performed by the generator 40 in the series mode.

As shown in FIG. 3, the parallel mode is a traveling mode in which the vehicle is driven mainly by the engine 2 and the driving of the vehicle is assisted by the motor 20 as necessary, and is selected when the traveling load is high. In the parallel mode, the clutch mechanism 60 is in a state where the generator 40 and the speed reduction device 30 are connected. As a result, the power of the engine 2 is transmitted to the axle AX via the generator 40, the clutch mechanism 60, the speed reduction device 30, and the differential device 50. More specifically, when the rotor 41 of the generator 40 is rotated by the engine 2, the rotation of the engine drive shaft 42 is changed to the first flange portion 62, the movable portion 65, the second flange portion 63, the clutch shaft 61, and the engine drive. The gear 64, the counter gear 32, the counter shaft 34, the drive gear 33, the ring gear 51, and the axle AX are transmitted in this order. Thereby, the axle shaft AX and the wheel H can be rotated by the engine 2, and the vehicle can be run.

In the parallel mode, the rotation of the motor shaft 22 is transmitted from the motor drive gear 31 to the counter gear 32. Thereby, the rotation operation of the engine 2 can be assisted by the motor 20. Thus, according to the present embodiment, since the counter gear 32 meshes with both the engine drive gear 64 and the motor drive gear 31, the counter gear 32 has the power of the engine 2 and the power of the motor 20 in the parallel mode. Both are communicated. Therefore, the power transmission path from the counter gear 32 to the axle AX can be supplied by the power transmission path from the engine 2 to the axle AX and the power transmission path from the motor 20 to the axle AX. Thereby, the number of shafts and gears necessary for transmitting power from the motor 20 and the engine 2 to the axle AX can be reduced. Therefore, the motor unit 10 can be further reduced in size and weight.

Further, according to the present embodiment, the reduction ratio of the rotation of the motor 20 can be changed by changing the number of teeth of the motor drive gear 31, and the rotation of the engine 2 can be changed by changing the number of teeth of the engine drive gear 64. The reduction ratio can be changed. That is, by changing the number of teeth of each drive gear, the reduction ratio of the motor 20 and the reduction ratio of the engine 2 can be individually changed, and can be made different from each other. Thereby, the reduction ratio of the motor 20 and the reduction ratio of the engine 2 can be set to suitable values, respectively. Therefore, the vehicle can be driven efficiently regardless of whether the motor 20 or the engine 2 is driven by either one or both.

Also, as described above, the oil pump (not shown) in the present embodiment is driven by the power of the engine 2 and is not driven in the EV mode in which the engine 2 is stopped. In this case, since the oil O is not supplied to the motor 20 by the oil pump, the motor 20 may be insufficiently cooled. On the other hand, since the ring gear 51 is driven in any mode, cooling using the oil O scraped up by the ring gear 51 is performed in any mode. However, it is difficult to supply the oil O to the gap between the motor shaft 22 and the axle AX by simply scooping up the oil O by the ring gear 51.

In contrast, according to the present embodiment, the oil O can be efficiently supplied to the gap between the motor shaft 22 and the axle AX by the storage unit 70 as described above. Therefore, the oil O scraped up by the ring gear 51 can be efficiently collected and supplied to the motor 20. Thereby, even in the EV mode and the series mode in which the oil pump is not driven, it is easy to sufficiently supply the oil 20 to the motor 20 and it is possible to suppress the cooling of the motor 20 from being insufficient.

The present invention is not limited to the above-described embodiment, and other configurations can be adopted. The wall part which comprises a storage part does not need to contain a part of partition wall part. Only a part of the radial gap between the motor shaft and the axle of the opening on the right side of the motor shaft may be located inside the reservoir. Oil O may be supplied to the reservoir by an oil pump. The housing may not have a partition wall portion. The configuration of the clutch mechanism is not particularly limited. The clutch mechanism may not be provided. In this case, the engine power may not be transmitted to the differential device, but may be used only for power generation by the generator. The configuration of the speed reduction mechanism is not particularly limited. The configuration of the differential device is not particularly limited. In the reduction gear, the gear that meshes with the motor drive gear and the gear that meshes with the engine drive gear may be different gears. The configuration of the generator is not particularly limited. The generator may not be provided. The oil pump may not be provided.

The vehicle on which the motor unit of the above-described embodiment is mounted may be a vehicle other than a vehicle that uses a motor unit and an engine as power sources as long as the axle is rotated by the motor unit, and is not particularly limited. . For example, the motor unit of the above-described embodiment may be mounted on an electric vehicle (EV) that does not include an engine. Moreover, each structure demonstrated in this specification can be suitably combined in the range which is not mutually contradictory.

Claims

A motor unit for rotating the axle of a vehicle,
A motor having a motor shaft that rotates about the motor shaft;
A reduction gear connected to the motor shaft;
A differential device connected to the speed reducer and rotating the axle around a differential axis;
A housing having a motor housing portion that houses the motor, and a gear housing portion that houses the speed reduction device and the differential device and in which oil is housed.
A storage portion that opens upward in the vertical direction inside the gear housing portion and can store oil; and
With
The differential axis coincides with the motor axis;
The motor shaft is a hollow shaft that opens on both sides in the axial direction,
The axle is passed through the motor shaft,
One end of the motor shaft in the axial direction protrudes into the gear housing portion,
A motor unit in which at least a part of a radial clearance between the motor shaft and the axle in the opening on one side in the axial direction of the motor shaft is located inside the storage portion.
The differential device has a ring gear that rotates about the differential axis,
An oil sump for storing oil is provided in a region on the lower side in the vertical direction of the gear housing portion,
The motor unit according to claim 1, wherein an end of the ring gear on a lower side in the vertical direction is immersed in the oil reservoir.
3. The motor unit according to claim 1, wherein the motor shaft has a shaft through hole that connects the inside of the motor shaft and the outer peripheral surface of the motor shaft.
The housing has a partition wall portion that partitions the motor housing portion and the gear housing portion,
The motor unit according to any one of claims 1 to 3, wherein a part of the wall part constituting the storage part is a part of the partition wall part.
Oil is stored inside the motor storage portion,
The partition wall has an oil passage that connects the inside of the motor housing and the inside of the gear housing,
The oil in the motor housing portion is movable to the inside of the gear housing portion through the oil passage.
The motor unit according to claim 4.