Drive unit

Abstract

To provide a driving device having a structure capable of facilitating the flow of a fluid into a passage.SOLUTION: A driving device 100 includes; a motor 20 having a rotor 21 and a stator 22 opposed to the rotor via a gap; a gear mechanism 30 connected to the rotor; a housing 10 having a motor housing 11 inside which the motor is housed, and a gear housing 12 inside which the gear mechanism is housed; a passage 90 at least a part of which is constituted by the housing; and a mechanical pump 70 connected to the passage. The housing has a partition wall part 13 which separates the interior of the motor housing from the interior of the gear housing. The passage includes: a partition wall passage portion 93 provided in the partition wall part; and a motor housing passage part 94 provided in the motor housing and connected to the partition wall passage part. A mechanical pump is connected to a rotating shaft provided in the motor or the gear mechanism and provided in the partition wall part.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a driving device.

Background Art

[0002] A driving device including a pump for sending oil is known. For example, Patent Document 1 describes a driving device mounted on an electric vehicle as such a driving device.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the driving device as described above, an oil passage for flowing oil by a pump is provided. If such an oil passage is simply provided in a housing or the like, the oil passage may become long and it may be difficult to send oil.

[0005] In view of the above circumstances, an object of the present invention is to provide a driving device having a structure that enables fluid to flow easily in a flow path.

Means for Solving the Problems

[0006] One embodiment of the drive device of the present invention comprises a motor having a rotor rotatable about a central axis and a stator facing the rotor with a gap between them, a gear mechanism connected to the rotor, a motor housing housing the motor and a gear housing housing the gear mechanism, a flow path formed at least in part by the housing, and a mechanical pump connected to the flow path. The housing has a partition wall separating the inside of the motor housing from the inside of the gear housing. The flow path has a partition wall flow path section provided in the partition wall section and a motor housing flow path section provided in the motor housing and connected to the partition wall flow path section. The mechanical pump is connected to a rotating shaft provided in the motor or the gear mechanism and is provided in the partition wall section. [Effects of the Invention]

[0007] According to one aspect of the present invention, a drive device can be made more efficient at facilitating the flow of fluid within a flow path. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a perspective view showing the drive unit of the first embodiment. [Figure 2] Figure 2 is a schematic cross-sectional view showing the drive device of the first embodiment. [Figure 3] Figure 3 is a cross-sectional view showing a mechanical pump according to the first embodiment. [Figure 4] Figure 4 is a cross-sectional view showing a part of the drive device of the second embodiment. [Figure 5] Figure 5 is a schematic cross-sectional view showing the drive device of the third embodiment. [Modes for carrying out the invention]

[0009] In the following description, the vertical direction will be defined and explained based on the positional relationship when the drive unit of the embodiment is mounted on a vehicle located on a horizontal road surface. In other words, the relative positional relationship with respect to the vertical direction described in the following embodiment only needs to be satisfied when the drive unit is mounted on a vehicle located on a horizontal road surface.

[0010] In the drawings, the XYZ coordinate system is shown as a three-dimensional Cartesian coordinate system where appropriate. In the XYZ coordinate system, the Z-axis direction is the vertical direction. The side in which the Z-axis arrow points (+Z side) is the vertically upward side, and the side opposite to the side in which the Z-axis arrow points (-Z side) is the vertically downward side. In the following description, the vertically upward side will simply be referred to as the "upper side," and the vertically downward side will simply be referred to as the "lower side." The X-axis direction is perpendicular to the Z-axis direction and is the longitudinal direction of the vehicle on which the drive unit is mounted. In the following embodiments, the side in which the X-axis arrow points (+X side) is the front of the vehicle, and the side opposite to the side in which the X-axis arrow points (-X side) is the rear of the vehicle. The Y-axis direction is perpendicular to both the X-axis direction and the Z-axis direction and is the lateral direction of the vehicle, i.e., the vehicle width direction. In the following embodiment, the side indicated by the Y-axis arrow (+Y side) is the left side of the vehicle, and the side opposite to the Y-axis arrow (-Y side) is the right side of the vehicle. The longitudinal and lateral directions are horizontal directions perpendicular to the vertical direction.

[0011] Note that the front-to-back positional relationship is not limited to the positional relationship of the embodiments described below. The side in which the X-axis arrow points (+X side) may be the rear of the vehicle, and the side opposite to the side in which the X-axis arrow points (-X side) may be the front of the vehicle. In this case, the side in which the Y-axis arrow points (+Y side) is the right side of the vehicle, and the side opposite to the side in which the Y-axis arrow points (-Y side) is the left side of the vehicle. Furthermore, in this specification, "parallel direction" includes substantially parallel directions, and "orthogonal direction" includes substantially orthogonal directions.

[0012] The central axis J1, as shown in the diagrams, is a virtual axis extending in a direction intersecting the vertical direction. More specifically, the central axis J1 extends in the Y-axis direction perpendicular to the vertical direction, that is, in the left-right direction of the vehicle. In the following description, unless otherwise specified, the direction parallel to the central axis J1 will be simply called the "axial direction," the radial direction centered on the central axis J1 will be simply called the "radial direction," and the circumferential direction centered on the central axis J1, that is, around the axis of the central axis J1, will be simply called the "circumferential direction." In the following embodiments, the left side (+Y side) will be called the "axial side," and the right side (-Y side) will be called the "axial side."

[0013] <First Embodiment> The drive unit 100 of this embodiment shown in Figure 1 is a drive unit mounted on a vehicle that rotates the axle 39. The vehicle on which the drive unit 100 is mounted is a vehicle that uses a motor as a power source, such as a hybrid electric vehicle (HEV), a plug-in hybrid vehicle (PHV), or an electric vehicle (EV). As shown in Figure 1, the drive unit 100 comprises a housing 10 and an inverter unit 50. As shown in Figure 2, the drive unit 100 comprises a motor 20, a gear mechanism 30, and a mechanical pump 70.

[0014] The housing 10 includes a motor housing 11 that houses the motor 20, a gear housing 12 that houses the gear mechanism 30, and a partition wall 13 that separates the interior of the motor housing 11 from the interior of the gear housing 12. In this embodiment, the gear housing 12 is connected to one axial side (+Y side) of the motor housing 11. The partition wall 13 separates the interior of the motor housing 11 from the interior of the gear housing 12 in the axial direction. The partition wall 13 has a hole 13a that penetrates the partition wall 13 in the axial direction. The partition wall 13 has a partition wall opening 13b that connects the interior of the motor housing 11 from the interior of the gear housing 12.

[0015] As shown in Figure 3, the partition wall portion 13 has a retaining hole portion 13c that is recessed from one axial side (+Y side) of the partition wall portion 13 to the other axial side (-Y side). The retaining hole portion 13c is a circular hole centered on the intermediate axis J2, which will be described later. The retaining hole portion 13c is a hole with a bottom on the other axial side. The retaining hole portion 13c has a large diameter hole portion 13d and a small diameter hole portion 13e. The large diameter hole portion 13d opens to one axial side of the partition wall portion 13. The small diameter hole portion 13e is connected to the other axial side of the large diameter hole portion 13d. The inner diameter of the small diameter hole portion 13e is smaller than the inner diameter of the large diameter hole portion 13d. An annular groove portion 13f extending around the intermediate axis J2 is provided on the inner circumferential surface of the small diameter hole portion 13e.

[0016] The motor housing 11 is substantially cylindrical in shape and extends in the axial direction. As shown in Figure 2, the motor housing 11 includes a motor housing body 11a and a motor cover 14. In this embodiment, the motor housing body 11a and the motor cover 14 are separate components. However, the motor housing body 11a and the motor cover 14 may be parts of the same single component.

[0017] The motor housing body 11a is the peripheral wall portion that surrounds the motor 20 around the central axis J1. The motor cover 14 is the wall portion on the other axial side (-Y side) of the wall portion that constitutes the motor housing 11. The motor cover 14 is located on the other axial side of the motor 20. In this embodiment, the motor cover 14 corresponds to the "first wall portion" which is positioned between the partition wall portion 13 and the internal space of the motor housing 11. A retaining hole portion 14a is provided on the surface of the motor cover 14 on one axial side (+Y side) that is recessed on the other axial side.

[0018] The gear housing 12 includes a gear housing body 12a and a gear cover 15. In this embodiment, the gear housing body 12a and the gear cover 15 are separate components. However, the gear housing body 12a and the gear cover 15 may be parts of the same single component.

[0019] The gear housing body 12a is a peripheral wall portion that surrounds the gear mechanism 30 around the central axis J1. The gear cover 15 is a wall portion on one axial side (+Y side) among the wall portions constituting the gear housing 12. The gear cover 15 is located on one axial side of the gear mechanism 30. The bottom portion located on the lower side of the gear housing 12 is located lower than the bottom portion located on the lower side of the motor housing 11.

[0020] Inside the gear housing 12, oil O as a fluid is accommodated. The oil O is stored in the lower region inside the gear housing 12. The oil O flows in the flow path 90 described later. In the present embodiment, the oil O is used as a refrigerant for cooling the motor 20. Further, the oil O is used as a lubricating oil for the gear mechanism 30 and each bearing described later. As the oil O, for example, in order to exhibit the functions of a refrigerant and a lubricating oil, it is preferable to use an oil equivalent to an automatic transmission lubricating oil (ATF: Automatic Transmission Fluid) having a relatively low viscosity.

[0021] The motor 20 has a rotor 21 that is rotatable about the central axis J1, and a stator 22 that faces the rotor 21 with a gap therebetween. The rotor 21 has a hollow motor shaft 23, a rotor core 24a fixed to the outer peripheral surface of the motor shaft 23, and a magnet 24b fixed to the rotor core 24a. The motor shaft 23 is cylindrical with openings on both axial sides about the central axis J1. The motor shaft 23 has through holes 23a that penetrate the wall portion of the motor shaft 23 in the radial direction from the inner peripheral surface to the outer peripheral surface of the motor shaft 23. A plurality of through holes 23a are provided at intervals in the circumferential direction.

[0022] The other axial end (-Y side) of the motor shaft 23 is supported by the motor cover 14 via a bearing 41. The other axial end (+Y side) of the motor shaft 23 is supported by the partition wall 13 via a bearing 42. The rotor 21 is rotatably supported around the central axis J1 by the bearings 41 and 42. In other words, in this embodiment, the drive unit 100 includes bearings 41 and 42 that rotatably support the rotor 21. Bearing 41 is held in a holding hole 14a of the motor cover 14 and supports the other axial end of the motor shaft 23. Bearing 42 is held in a hole 13a of the partition wall 13 and supports the other axial end of the motor shaft 23. Bearings 41 and 42 are, for example, ball bearings. In this embodiment, bearing 41 corresponds to the "second bearing".

[0023] The stator 22 is located radially outward from the rotor 21. The stator 22 is fixed inside the motor housing 11. The stator 22 has an annular stator core 25 surrounding the rotor 21 and a plurality of coils 26 attached to the stator core 25.

[0024] The gear mechanism 30 is connected to the rotor 21. More specifically, the gear mechanism 30 is connected to one axial end (+Y side) of the motor shaft 23. The gear mechanism 30 includes a reduction gear 31 and a differential gear 32. The reduction gear 31 is connected to one axial end of the motor shaft 23. The reduction gear 31 includes a first gear shaft 33, a first gear 34, a second gear 35, a third gear 36, and a second gear shaft 37. In other words, the gear mechanism 30 includes a first gear shaft 33, a first gear 34, a second gear 35, a third gear 36, and a second gear shaft 37.

[0025] The first gear shaft 33 is connected to one axial side (+Y side) of the motor shaft 23. The first gear shaft 33 is a hollow shaft extending in the axial direction. The first gear shaft 33 is cylindrical with a central axis J1 as its center and openings on both axial sides. The other axial end (-Y side) of the first gear shaft 33 is fitted inside the motor shaft 23. In this embodiment, the other axial end of the first gear shaft 33 is connected to one axial end of the motor shaft 23 by spline fitting. The first gear shaft 33 is rotatably supported around the central axis J1 by a bearing 43 held in the hole 13a of the partition wall 13 and a bearing 44 held in the gear cover 15. The bearings 43 and 44 are, for example, ball bearings.

[0026] The first gear 34 is fixed to the outer surface of the first gear shaft 33. Thus, the first gear 34 is connected to the rotor 21 via the first gear shaft 33. The first gear shaft 33 and the first gear 34 rotate together with the rotor 21 around the central axis J1.

[0027] The second gear shaft 37 extends in the axial direction. The second gear shaft 37 is cylindrical with an intermediate axis J2 that extends in the axial direction as its center. The intermediate axis J2 is a virtual axis parallel to the central axis J1. The intermediate axis J2 is located, for example, below the central axis J1. In this embodiment, the second gear shaft 37 is a shaft provided in the gear mechanism 30 and rotates together with the second gear 35. In this embodiment, the second gear shaft 37 corresponds to a "rotating shaft". As shown in Figure 3, the second gear shaft 37 has a second gear shaft body 37a that extends in the axial direction and a pump connecting portion 37b that is connected to the other axial side (-Y side) of the second gear shaft body 37a.

[0028] As shown in Figure 2, one axial end (+Y side) of the second gear shaft body 37a is rotatably supported by a bearing 45 held in the gear cover 15. As shown in Figure 3, the other axial end (-Y side) of the second gear shaft body 37a is rotatably supported by a bearing 46 held in the partition wall 13. The bearing 46 is held in a large-diameter hole 13d. The bearings 45 and 46 are, for example, ball bearings. In this embodiment, the bearing 46 is held in the partition wall 13 and corresponds to the "first bearing" that supports the second gear shaft 37 as a rotating shaft. The second gear shaft body 37a has a connecting hole 37e. The connecting hole 37e is recessed in one axial direction from the other axial end face of the second gear shaft body 37a.

[0029] The pump connector 37b is cylindrical in shape, extending axially around the intermediate shaft J2. The outer diameter of the pump connector 37b is smaller than the outer diameter of the second gear shaft body 37a. The pump connector 37b has a first connector 37c and a second connector 37d. The first connector 37c protrudes axially to the other side (-Y side) of the second gear shaft body 37a. The axial end of the first connector 37c is connected to the mechanical pump 70. The second connector 37d is connected to one side (+Y side) of the first connector 37c. The second connector 37d is fitted into the connector hole 37e. The second connector 37d is connected to the axial end of the second gear shaft body 37a by spline fitting. The outer diameter of the second connector 37d is larger than the outer diameter of the first connector 37c.

[0030] As shown in Figure 2, the second gear 35 and the third gear 36 are fixed to the outer circumferential surface of the second gear shaft 37. More specifically, the second gear 35 and the third gear 36 are fixed to the outer circumferential surface of the second gear shaft body 37a. The second gear 35 meshes with the first gear 34. The third gear 36 meshes with the ring gear 38 of the differential 32, which will be described later. The rotational speed of the first gear shaft 33 and the first gear 34 are the same as the rotational speed of the rotor 21. The rotational speed of the second gear 35, the rotational speed of the third gear 36, and the rotational speed of the second gear shaft 37 are smaller than the rotational speed of the rotor 21.

[0031] The differential gear 32 has a ring gear 38. Torque output from the motor 20 is transmitted to the ring gear 38 via the reduction gear 31. The lower end of the ring gear 38 is immersed in oil O stored in the gear housing 12. As the ring gear 38 rotates, the oil O is scooped up. The scooped-up oil O is supplied as lubricant to, for example, the reduction gear 31 and the differential gear 32. The differential gear 32 rotates the axle 39 around the differential shaft J3. The differential shaft J3 is a virtual shaft extending parallel to the central axis J1.

[0032] The mechanical pump 70 is located in the partition wall 13. The mechanical pump 70 is connected to the flow path 90, which will be described later. The mechanical pump 70 is connected to the other axial end (-Y side) of the second gear shaft 37. As shown in Figure 3, the mechanical pump 70 has an inner rotor 71 and an outer rotor 72 surrounding the inner rotor 71. The inner rotor 71 and the outer rotor 72 are annular in shape, surrounding the intermediate shaft J2. The first connecting portion 37c of the pump connecting portion 37b is fitted inside the inner rotor 71. The inner rotor 71 is connected to the pump connecting portion 37b in a way that prevents relative rotation around the intermediate shaft J2. Although not shown in the figure, multiple teeth are provided on the outer circumferential surface of the inner rotor 71 and the inner circumferential surface of the outer rotor 72. The teeth of the inner rotor 71 and the teeth of the outer rotor 72 mesh with each other.

[0033] The inner rotor 71 and outer rotor 72 are located within the small-diameter hole portion 13e of the retaining hole portion 13c. In this embodiment, the inner rotor 71 and outer rotor 72 are held within the retaining hole portion 13c by a retaining member 76. The retaining member 76 is a cylindrical member that opens to the other axial side (-Y side). The retaining member 76 is fitted into the small-diameter hole portion 13e. The retaining member 76 has a disc portion 76a located on one axial side (+Y side) of the inner rotor 71 and outer rotor 72, and a cylindrical portion 76b that protrudes from the outer peripheral edge of the disc portion 76a to the other axial side.

[0034] The disc portion 76a supports the inner rotor 71 and the outer rotor 72 from one axial side (+Y side). An annular recess 76c is provided on the outer peripheral edge of the axial side surface of the disc portion 76a, recessing toward the other axial side (-Y side). The disc portion 76a has a hole 76d that penetrates the disc portion 76a in the axial direction. The first connecting portion 37c is passed through the hole 76d in the axial direction. The inner rotor 71 and the outer rotor 72 are housed inside the cylindrical portion 76b. The other axial end of the cylindrical portion 76b is in contact with, for example, the bottom surface of the other axial side of the retaining hole portion 13c.

[0035] The retaining member 76 is supported from one axial side (+Y side) by a snap ring 77 fitted into the groove 13f. This prevents the retaining member 76 from moving in one axial direction. Although not shown in the figure, the snap ring 77 is C-shaped and surrounds the intermediate shaft J2. The snap ring 77 supports the annular recess 76c from one axial side. The opening on the other axial side (-Y side) of the retaining member 76 is closed by the bottom surface on the other axial side of the retaining hole 13c, thereby forming a pump chamber 73 that houses the inner rotor 71 and the outer rotor 72.

[0036] The mechanical pump 70 has an intake section 74 for drawing in oil O and a discharge section 75 for discharging oil O. In this embodiment, the discharge section 75 is located above the intake section 74. When the inner rotor 71 rotates as the second gear shaft 37 rotates, the outer rotor 72 that meshes with the inner rotor 71 also rotates. As the inner rotor 71 and outer rotor 72 rotate, oil O is drawn in between the inner rotor 71 and the outer rotor 72 via the intake section 74. The oil O drawn in between the inner rotor 71 and the outer rotor 72 is sent to the discharge section 75 as the inner rotor 71 and outer rotor 72 rotate, and is discharged from the discharge section 75 to the outside of the mechanical pump 70.

[0037] As shown in Figure 2, in this embodiment, the drive unit 100 includes a first storage section 61, a second storage section 62, and a third storage section 63. The first storage section 61, the second storage section 62, and the third storage section 63 are capable of storing oil O. The first storage section 61 and the second storage section 62 are located inside the gear housing 12. The third storage section 63 is located inside the motor housing 11.

[0038] The first storage section 61 is formed by the lower portion of the gear housing 12. The interior of the first storage section 61 is the lower region inside the gear housing 12. Part of the first storage section 61 is formed by the bottom of the gear housing 12. When oil O is stored in the first storage section 61, an oil reservoir P is formed in the lower region inside the gear housing 12. The lower end of the ring gear 38 is located inside the first storage section 61. The lower end of the ring gear 38 is the lower end of the gear mechanism 30. In other words, in this embodiment, the lower end of the gear mechanism 30 is located inside the first storage section 61. As a result, the lower end of the ring gear 38 is immersed in the oil reservoir P.

[0039] The second storage section 62 is located above the first storage section 61. In this embodiment, the second storage section 62 is located above the gear mechanism 30. The second storage section 62 is open upwards. The second storage section 62 is, for example, trough-shaped. At least a portion of the oil O scraped up by the ring gear 38 is stored inside the second storage section 62. The second storage section 62 has a plurality of supply ports 62a. The oil O stored in the second storage section 62 is supplied from the supply ports 62a to the bearings 43, 44, 45, 46 that rotatably support the first gear shaft 33 and the second gear shaft 37, and to the gear mechanism 30.

[0040] In this embodiment, the third storage section 63 is located inside the motor housing 11 on the other axial side (-Y side) of the stator 22. The third storage section 63 is located above the bearing 41 held by the motor cover 14 and below the motor housing flow path section 94, which will be described later. The third storage section 63 is open to the top. The third storage section 63 is, for example, trough-shaped. The third storage section 63 is capable of storing oil O flowing through the motor housing flow path section 94. The third storage section 63 has a supply port 63a for supplying oil O to the bearing 41 held by the motor cover 14.

[0041] In this embodiment, the drive unit 100 includes a flow path 90 which is at least partially formed by the housing 10. In this embodiment, the flow path 90 is an oil passage through which oil O flows. The flow path 90 includes a partition flow path section 93, a motor housing flow path section 94, a shaft internal flow path section 95, and a rotor core internal flow path section 96.

[0042] As shown in Figure 2, the partition channel section 93 is provided in the partition section 13. The partition channel section 93 has a first partition channel section 93a and a second partition channel section 93b. The first partition channel section 93a extends vertically. The lower end of the first partition channel section 93a opens into the interior of the first storage section 61. As shown in Figure 3, the upper end of the first partition channel section 93a is connected to the suction section 74 of the mechanical pump 70. The second partition channel section 93b is located above the first partition channel section 93a. The second partition channel section 93b extends vertically. The lower end of the second partition channel section 93b is connected to the discharge section 75 of the mechanical pump 70. In this embodiment, the partition channel section 93 is connected to the bearing 46 held in the large-diameter hole section 13d via the gap between the inner rotor 71 and the retaining member 76, the gap between the outer rotor 72 and the retaining member 76, and the gap between the hole 76d of the retaining member 76 and the second gear shaft 37.

[0043] As shown in Figure 2, the motor housing flow path section 94 is provided in the motor housing 11. In this specification, "the motor housing flow path section is provided in the motor housing" includes the motor housing flow path section being located in the internal space of the motor housing that houses the motor, and the motor housing flow path section being provided in the wall portion that constitutes the motor housing. In this embodiment, the motor housing flow path section 94 is located in the internal space of the motor housing 11 that houses the motor 20. The motor housing flow path section 94 is located above the stator 22. The motor housing flow path section 94 is located above the third storage section 63.

[0044] In this embodiment, the motor housing flow path 94 extends in the axial direction. The motor housing flow path 94 is connected to the partition wall flow path 93. More specifically, one axial end (+Y side) of the motor housing flow path 94 is connected to the upper end of the second partition wall flow path 93b. In this embodiment, the motor housing flow path 94 is composed of the interior of a tubular member 94p that extends in the axial direction and opens on both axial sides. One axial end (+Y side) of the tubular member 94p is held by the partition wall 13. The other axial end (-Y side) of the tubular member 94p is held by the motor cover 14.

[0045] The motor housing flow path section 94 is provided with a plurality of supply ports 94a. The supply ports 94a open downwards. In this embodiment, each supply port 94a is formed by a hole provided in the lower part of the wall of the pipe member 94p. The plurality of supply ports 94a include a supply port 94a that supplies oil O to the stator 22 from above, a supply port 94a that supplies oil O to the bearing 42 held by the partition wall section 13 from above, and a supply port 94a that supplies oil O to the third storage section 63 from above.

[0046] The internal shaft flow path 95 is at least partially comprised of the inside of the motor shaft 23. In this embodiment, the internal shaft flow path 95 is comprised of the inside of the motor shaft 23 and the inside of the first gear shaft 33. The internal shaft flow path 95 extends from the motor cover 14, through the partition wall 13 in the axial direction, to the gear cover 15. The internal shaft flow path 95 is connected to the motor housing flow path 94.

[0047] In this specification, "two flow channels are connected" means that fluid can flow from one of the two flow channels to the other. In this embodiment, a portion of the oil O flowing through the motor housing flow channel 94 is supplied from the supply port 94a to the third storage section 63, and then supplied from the supply port 63a of the third storage section 63 to the bearing 41. The oil O supplied to the bearing 41 flows from the holding hole 14a in which the bearing 41 is held into the other axial end (-Y side) of the motor shaft 23. This allows the oil O to flow from the motor housing flow channel 94 to the shaft internal flow channel 95.

[0048] The internal flow channel 96 of the rotor core is provided in the rotor core 24a. The internal flow channel 96 of the rotor core is connected to the internal flow channel 95 of the shaft via a through hole 23a. The internal flow channel 96 of the rotor core opens at both axial ends of the rotor core 24a.

[0049] When the motor 20 is driven, the second gear shaft 37 rotates around the intermediate shaft J2, causing the inner rotor 71 to rotate around the intermediate shaft J2 and the mechanical pump 70 to drive. When the mechanical pump 70 is driven, oil O from the oil reservoir P is drawn into the flow path 90 from the lower end of the first partition flow path 93a. The oil O drawn into the flow path 90 flows through the first partition flow path 93a, the mechanical pump 70, and the second partition flow path 93b in that order, and flows into the motor housing flow path 94. The oil O that flows into the motor housing flow path 94 is discharged into the motor housing 11 from multiple supply ports 94a. A portion of the oil O discharged from the multiple supply ports 94a is supplied to the bearing 42 and the stator 22. This allows oil O to be supplied to the bearing 42 as lubricant and the stator 22 to be cooled by the oil O. The oil O supplied to the bearing 42 and stator 22 from the supply port 94a falls downward and accumulates in the lower region of the motor housing 11. The oil O accumulated in the lower region of the motor housing 11 returns to the gear housing 12 through the partition opening 13b provided in the partition wall 13.

[0050] A portion of the oil O discharged from the multiple supply ports 94a is stored in the third storage section 63. The oil O stored in the third storage section 63 is supplied to the bearing 41 from the supply port 63a. At least a portion of the oil O supplied to the bearing 41 flows into the shaft internal flow section 95 through the retaining hole section 14a. A portion of the oil O that flows into the shaft internal flow section 95 flows into the rotor core internal flow section 96 through the through hole 23a. The oil O that flows into the rotor core internal flow section 96 is scattered radially outward from both axial ends of the rotor core 24a and supplied to the coil 26. This allows the stator 22 to be cooled more by the oil O. The oil O supplied from the rotor core internal flow section 96 to the coil 26 returns into the gear housing 12 through the partition opening 13b, similar to the oil O supplied from the supply port 94a to the bearing 42 and the stator 22.

[0051] Another portion of the oil O that flows into the shaft internal flow path 95 is supplied to the portion where the motor shaft 23 and the first gear shaft 33 are spline-fitted. Yet another portion of the oil O that flows into the shaft internal flow path 95 flows from the inside of the motor shaft 23 into the inside of the first gear shaft 33 and returns to the gear housing 12 from one axial end (+Y side) of the first gear shaft 33.

[0052] According to this embodiment, the drive unit 100 includes a mechanical pump 70 connected to the flow path 90. The mechanical pump 70 is connected to a second gear shaft 37, which is a rotating shaft provided in the gear mechanism 30. Therefore, as the second gear shaft 37 rotates in conjunction with the drive of the motor 20, the mechanical pump 70 is driven, allowing oil O to flow into the flow path 90. This makes it possible to flow oil O into the flow path 90 without using an electric pump. Consequently, circuits for controlling the electric pump and wiring connected to the electric pump become unnecessary, reducing the number of parts in the drive unit 100. Furthermore, the manufacturing cost of the drive unit 100 can be reduced. In addition, the drive unit 100 can be made smaller compared to the case where an electric pump is provided.

[0053] Furthermore, according to this embodiment, the mechanical pump 70 is provided in the partition wall 13. The flow path 90 has a partition wall flow path section 93 provided in the partition wall 13 and a motor housing flow path section 94 provided in the motor housing 11 and connected to the partition wall flow path section 93. By providing a part of the flow path 90 in the partition wall 13 in this way, it is possible to easily connect the inside of the motor housing 11 and the inside of the gear housing 12, which are separated by the partition wall 13, through the flow path 90. As a result, the overall length of the flow path 90 can be easily reduced. This reduces the pressure loss of the oil O flowing through the flow path 90. As a result, it is possible to easily flow the oil O into the flow path 90. As a result, the oil O can be suitably supplied to various parts such as the stator 22 via the flow path 90. In addition, since the mechanical pump 70 is provided in the partition wall 13, the mechanical pump 70 can be easily connected to the partition wall flow path section 93 provided in the partition wall 13. Furthermore, since there is no need to provide a separate passage connecting the mechanical pump 70 and the partition passage section 93 in another part, the overall length of the passage 90 can be made smaller. This further reduces the pressure loss of the oil O flowing through the passage 90. Therefore, it is possible to make it easier for the oil O to flow through the passage 90.

[0054] Furthermore, according to this embodiment, the partition channel 93 is connected to the bearing 46, which acts as the first bearing supporting the second gear shaft 37. Therefore, a portion of the oil O flowing through the partition channel 93 can be supplied to the bearing 46 that supports the second gear shaft 37, which acts as a rotating shaft connected to the mechanical pump 70.

[0055] Furthermore, according to this embodiment, the rotating shaft to which the mechanical pump 70 is connected is a second gear shaft 37 provided in the gear mechanism 30 and rotating together with the second gear 35. Here, the second gear 35 is a gear that meshes with the first gear 34 connected to the rotor 21. Therefore, the rotational speed of the second gear shaft 37, which rotates together with the second gear 35, can be made smaller than the rotational speed of the rotor 21. This makes it possible to reduce the rotational speed of the rotating shaft that drives the mechanical pump 70 compared to, for example, the case where the mechanical pump 70 is connected to the motor shaft 23 and the first gear shaft 33 that rotates together with the motor shaft 23. Consequently, it is possible to suppress excessive suction of oil O from the gear housing 12 by the mechanical pump 70. Therefore, it is possible to suppress a decrease in the amount of oil O stored in the first storage section 61, and to suppress a decrease in the amount of oil O scraped up by the ring gear 38 in the gear housing 12. This prevents a decrease in the amount of oil O supplied to the gear mechanism 30 as lubricant.

[0056] Furthermore, according to this embodiment, the flow path 90 has a shaft-internal flow path 95 which is at least partly formed inside the motor shaft 23 and connected to the motor housing flow path 94, and a rotor core-internal flow path 96 which is provided on the rotor core 24a and connected to the shaft-internal flow path 95. Therefore, the oil O that flows into the motor housing flow path 94 can flow into the shaft-internal flow path 95 and the rotor core-internal flow path 96. This allows the rotor 21 to be suitably cooled by the oil O. In particular, by suitably cooling the magnet 24b of the rotor 21, it is possible to suppress the temperature of the magnet 24b from becoming high and to suppress the demagnetization of the magnet 24b. Therefore, it is possible to suppress a decrease in the output torque of the motor 20. As a result, even if an inexpensive magnet with relatively low magnetic force is used as the magnet 24b, it is possible to maintain the output of the drive unit 100 while using an inexpensive magnet 24b.

[0057] Furthermore, according to this embodiment, the drive unit 100 is provided inside the motor housing 11 and includes a third storage section 63 as a storage section capable of storing oil O flowing through the motor housing flow path 94. The third storage section 63 has a supply port 63a for supplying oil O to the bearing 41, which is the second bearing. Therefore, at least a portion of the oil O flowing through the motor housing flow path 94 can be suitably supplied to the bearing 41 via the third storage section 63.

[0058] Furthermore, according to this embodiment, the motor housing 11 has a motor cover 14 as a first wall portion positioned between the motor housing 11 and the partition wall portion 13, with the internal space of the motor housing 11 in between. The supply port 63a supplies oil O to the bearing 41 held by the motor cover 14. Since the motor cover 14 is located on the opposite side of the motor housing 11 from the partition wall portion 13, the distance from the partition wall portion 13 to the motor cover 14 is relatively large. Therefore, it may be difficult to supply the oil O flowing from the partition wall flow path portion 93 to the motor housing flow path portion 94 to the bearing 41 held by the motor cover 14. In contrast, in this embodiment, as described above, a third storage portion 63 is provided, making it easier to supply oil O to the bearing 41 via the third storage portion 63. In other words, the configuration of supplying oil O to the bearing 41 via the third storage portion 63 is more useful when the bearing 41 is held by the motor cover 14.

[0059] Furthermore, according to this embodiment, the rotor 21 has a hollow motor shaft 23 into which oil O from the third reservoir 63 is supplied. Therefore, oil O flowing through the motor housing flow path 94 can be suitably supplied into the motor shaft 23 via the third reservoir 63. This allows the rotor 21 to be suitably cooled by the oil O.

[0060] <Second Embodiment> In the following, components similar to those in the embodiments described above may be omitted from explanation by using the same reference numerals as appropriate. As shown in Figure 4, in the drive device 200 of this embodiment, the second gear shaft 237 of the gear mechanism 230 is a hollow shaft. The second gear shaft 237 is a cylindrical tubular member that is centered on the intermediate shaft J2 and opens on both sides in the axial direction. The second gear shaft 237 corresponds to the "rotating shaft" to which the mechanical pump 70 is connected. The second gear shaft 237 has a second gear shaft body 237a and a pump connecting portion 237b.

[0061] The configuration of the second gear shaft body 237a is the same as that of the second gear shaft body 37a in the first embodiment, except that it is a hollow tubular member that opens on both sides in the axial direction. The configuration of the pump connecting portion 237b is the same as that of the pump connecting portion 37b in the first embodiment, except that it is a hollow tubular member that opens on both sides in the axial direction. The pump connecting portion 237b is spline-fitted and connected to the end of the second gear shaft body 237a on the other axial side (-Y side). The interior of the second gear shaft body 237a and the interior of the pump connecting portion 237b are connected to each other.

[0062] The flow path 290 in this embodiment has a gear shaft internal flow path portion 292 formed by the interior of the second gear shaft 237. The axial end (+Y side) of the gear shaft internal flow path portion 292 is formed by the interior of the axial end of the second gear shaft body 237a and is connected to a retaining recess 15a provided in the gear cover 15. A bearing 45 that supports the axial end of the second gear shaft 237 is held in the retaining recess 15a. Thus, the gear shaft internal flow path portion 292, i.e., the interior of the second gear shaft 237, is connected to the bearing 45 via the retaining recess 15a. In this embodiment, the gear cover 15 corresponds to a "second wall portion" positioned between it and the partition wall portion 13, with the internal space of the gear housing 12 in between. The bearing 45 corresponds to a "third bearing" held by the gear cover 15 as the second wall portion.

[0063] The other axial end (-Y) of the gear shaft internal passage section 292 is formed by the interior of the other axial end of the pump connection section 237b. The other axial end of the gear shaft internal passage section 292 is connected to the lower end of the second partition passage section 293b in the partition passage section 293. As a result, the interior of the second gear shaft 237 is connected to the partition passage section 293. In this embodiment, a portion of the oil O discharged from the discharge section 75 into the second partition passage section 293b flows into the gear shaft internal passage section 292 from the other axial end of the second gear shaft 237. The oil O that flows into the gear shaft internal passage section 292 flows to one axial side (+Y side) and flows into the retaining recess 15a. The oil O that flows into the retaining recess 15a is supplied to the bearing 45. The other configurations of the partition passage section 293 are the same as the other configurations of the partition passage section 93 in the first embodiment. The other configurations of the flow path 290 are the same as those of the flow path 90 in the first embodiment. The other configurations of the drive unit 200 are the same as those of the drive unit 100 in the first embodiment.

[0064] In this embodiment, the second gear shaft 237, which serves as the rotating shaft, is a hollow shaft. The interior of the second gear shaft 237 is connected to the partition channel 293. Therefore, a portion of the oil O flowing through the partition channel 293 can be supplied to the second gear shaft 237. Furthermore, in this embodiment, the gear cover 15, which serves as the second wall and is positioned between the partition 13 and the internal space of the gear housing 12, holds a bearing 45, which serves as the third bearing supporting the second gear shaft 237. The interior of the second gear shaft 237, that is, the gear shaft internal channel 292, is connected to the bearing 45. Therefore, a portion of the oil O flowing through the partition channel 293 can be supplied to the bearing 45 via the interior of the second gear shaft 237. In this embodiment as well, similar to the first embodiment, a portion of the oil O flowing through the partition channel 293 is also supplied to the bearing 46. Thus, in this embodiment, a portion of the oil O flowing through the partition channel 293 can be supplied to the bearings 45 and 46 that support both axial ends of the second gear shaft 237.

[0065] <Third Embodiment> In the following description, components similar to those in the embodiments described above may be omitted from explanation by using the same reference numerals as appropriate. As shown in Figure 5, the drive unit 300 of this embodiment includes a stator holder 380. The stator holder 380 is housed inside the motor housing 11. The stator holder 380 is cylindrical and surrounds the stator 22 around the central axis J1. The outer circumferential surface of the stator core 25 is fixed to the inner circumferential surface of the stator holder 380. The outer circumferential surface of the stator holder 380 is fixed to the inner circumferential surface of the motor housing 11. A groove 380a is provided on the outer circumferential surface of the stator holder 380. The radially outer opening of the groove 380a is closed by the inner circumferential surface of the motor housing 11, thereby forming a refrigerant flow path 381. A refrigerant W flows through the refrigerant flow path 381. The refrigerant W is, for example, water. The stator 22 is cooled by the refrigerant W flowing through the refrigerant flow path 381. Furthermore, the refrigerant W can be any type of refrigerant, as long as it is capable of cooling the stator 22.

[0066] In this embodiment, the motor housing flow path section 394 in the flow path 390 is provided within the wall portion constituting the motor housing 11. Therefore, there is no need to provide a separate member to provide the motor housing flow path section 394. The motor housing flow path section 394 has a first motor housing flow path section 394a and a second motor housing flow path section 394b. The first motor housing flow path section 394a is provided in the wall portion located on the upper side of the motor housing body 11a. The first motor housing flow path section 394a extends in the axial direction. One axial end (+Y side) of the first motor housing flow path section 394a is connected to the upper end of the partition wall flow path section 93. The second motor housing flow path section 394b is provided in the motor cover 14. The second motor housing flow path section 394b extends downward from the other axial end (-Y side) of the first motor housing flow path section 394a. The lower end of the second motor housing flow path section 394b is connected to the retaining hole 14a. As a result, the oil O that flows from the partition wall passage section 93 into the motor housing passage section 394 flows into the shaft internal passage section 95 via the retaining hole section 14a. The other configurations of the drive unit 300 are the same as those of the drive unit 100 in the first embodiment.

[0067] The present invention is not limited to the embodiments described above, and other configurations and methods may be adopted within the scope of the technical idea of ​​the present invention. The rotating shaft to which the mechanical pump is connected may be any shaft provided in the motor or gear mechanism. The rotating shaft to which the mechanical pump is connected may be the motor shaft or the first gear shaft of the gear mechanism connected to the motor shaft. The mechanical pump may have any configuration as long as it is connected to the rotating shaft and provided in the partition wall. The structure of the mechanical pump is not particularly limited.

[0068] The flow path may have any configuration as long as it includes a partition flow path and a motor housing flow path. The motor housing flow path may have any configuration as long as it is provided in the motor housing. The motor housing flow path may be, for example, made of a trough-shaped member. The shaft internal flow path and the rotor core internal flow path are not required. A storage section provided inside the motor housing and capable of storing the fluid flowing through the motor housing flow path may be directly connected to the motor housing flow path. The storage section is not required. In this case, the fluid in the motor housing flow path may be directly guided to the shaft internal flow path. The fluid flowing through the flow path may be of any type.

[0069] The applications of the drive unit to which the present invention is applied are not particularly limited. The drive unit may be mounted on a vehicle for purposes other than rotating an axle, for example, or on equipment other than a vehicle. The orientation of the drive unit when it is used is not particularly limited. The central axis of the motor may be inclined with respect to a horizontal direction perpendicular to the vertical direction, or it may extend in the vertical direction. The configurations described herein can be combined as appropriate, within the limits of what is not mutually contradictory. [Explanation of Symbols]

[0070] 10…Housing, 11…Motor housing, 12…Gear housing, 13…Bulkhead, 14…Motor cover (first wall), 15…Gear cover (second wall), 20…Motor, 21…Rotor, 22…Stator, 23…Motor shaft, 24a…Rotor core, 30, 230…Gear mechanism, 34…First gear, 35…Second gear, 37, 237…Second gear shaft (rotating shaft), 41…Bearing (second bearing) Ring), 45...Bearing (3rd bearing), 46...Bearing (1st bearing), 63...3rd reservoir (reservation section), 63a...Supply port, 70...Mechanical pump, 90, 290, 390...Flow channels, 93, 293...Partitioned flow channel section, 94, 394...Motor housing flow channel section, 95...Shaft internal flow channel section, 96...Rotor core internal flow channel section, 100, 200, 300...Drive unit, J1...Central shaft, O...Oil (fluid)

Claims

1. A motor having a rotor that can rotate about a central axis and a stator that faces the rotor with a gap between them, A gear mechanism connected to the rotor, A housing having a motor housing that houses the motor inside, and a gear housing that houses the gear mechanism inside, A flow path, at least a portion of which is formed by the housing, A mechanical pump connected to the aforementioned flow path, Storage section and Equipped with, The housing has a partition wall that separates the inside of the motor housing from the inside of the gear housing. The aforementioned flow path is The partition wall channel section provided in the partition wall section, A motor housing flow path section is provided in the motor housing and is connected to the partition wall flow path section, It has, The mechanical pump is connected to a rotating shaft provided in the motor or the gear mechanism, and is provided in the partition wall. The partition channel section comprises a first partition channel section and a second partition channel section. The first partition channel is connected to the suction section of the mechanical pump. The second partition channel section is connected to the discharge section of the mechanical pump. The aforementioned rotating shaft is a hollow shaft. One end of the second partition channel is connected to the inside of the rotating shaft, The other end of the second partition channel is connected to the motor housing channel above the stator. The storage section is provided inside the motor housing, capable of storing the fluid flowing through the motor housing passage, and opens upward. The motor housing flow path section has a plurality of first supply ports that open downward inside the motor housing and is located above the storage section. The aforementioned plurality of first supply ports are, A first supply port located on the upper side of the stator, A first supply port located above the storage section, Includes, The storage unit is a drive device having a second supply port for supplying the fluid to a bearing that rotatably supports the rotor.

2. The drive device according to claim 1, wherein the partition wall portion holds a bearing that supports the rotating shaft and connects to the partition wall flow path portion.

3. The gear mechanism is, A first gear connected to the rotor, A second gear that meshes with the first gear, It has, The drive device according to claim 1 or 2, wherein the rotating shaft is a shaft provided in the gear mechanism and rotates together with the second gear.

4. The rotor is A hollow motor shaft, A rotor core fixed to the motor shaft, It has, The aforementioned flow path is At least a portion of it is formed inside the motor shaft, and the shaft internal flow path is connected to the motor housing flow path, A rotor core is provided with a rotor core internal flow channel that is connected to the shaft internal flow channel, A drive device according to any one of claims 1 to 3, having the following features.

5. The motor housing has a first wall portion that is positioned between it and the partition wall portion, with the internal space of the motor housing being separated. The drive device according to any one of claims 1 to 4, wherein the second supply port supplies the fluid to the bearing that holds the rotor in the first wall and rotatably supports the rotor.

6. The drive device according to any one of claims 1 to 5, wherein the rotor has a hollow motor shaft into which the fluid in the reservoir is supplied.

7. The gear housing has a second wall portion that is positioned between it and the partition wall portion, with the internal space of the gear housing being separated. The drive device according to any one of claims 1 to 6, wherein the second wall portion holds a bearing that supports the rotating shaft and connects the inside of the rotating shaft.

8. The drive device according to any one of claims 1 to 7, wherein the motor housing flow path is provided within the wall portion constituting the motor housing.

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