Drive device

Abstract

A drive device according to one embodiment of the present invention is provided with: a motor having a motor shaft capable of rotating about a motor axis; a transmission mechanism located on one side in the axial direction of the motor and having a plurality of gears for transmitting the power of the motor; a plurality of bearings that support the transmission mechanism; a housing provided with a motor chamber in which the motor is housed and a gear chamber in which the transmission mechanism is housed; a flow path through which a fluid flows, at least a part of the flow path being provided in the housing; and a pump that is disposed in the flow path and that sucks fluid from an inflow port that opens in the gear chamber and delivers the fluid by pressure. The gear chamber is provided with a partition wall that partitions the gear chamber into a first region and a second region. A ring gear having the largest diameter among the plurality of gears is disposed in the first region. An inflow port is disposed in the second region. The housing has a cylindrical portion that holds the bearing. The flow path has: a first flow path part that supplies a fluid to the inner peripheral surface of the cylindrical part; and a second flow path portion extending from the inner peripheral surface of the cylindrical portion to an opening end located in the first region.

Description

Technical Field

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

[0002] This application claims priority based on Japanese Patent Application No. 2022-212388 filed in Japan on December 28, 2022, the contents of which are cited here. Background Art

[0003] In recent years, as a drive device mounted on an electric vehicle, a drive device having a housing having a motor chamber for accommodating a motor, a gear chamber for accommodating a transmission mechanism, and a partition wall separating the two chambers is known. In addition, a fluid such as oil is stored inside such a drive device, and the fluid is used to lubricate the gears and bearings in the drive device and cool the motor. Patent document 1 discloses a structure for supplying fluid to a motor using a pump.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2019-106776 Summary of the invention

[0007] Problems to be solved by the invention

[0008] When the gear is lifted, the gear sometimes draws air into the fluid, so the pump sucks the air (bubbles) in the fluid, which may reduce the pump's efficiency in pumping the fluid. Therefore, it is considered to set a partition wall around the gear to prevent the bubbles in the fluid from reaching the pump's suction port. However, in this case, there is the following problem: as the gear lifts the fluid, the fluid level around the gear decreases, and the lifting amount of the gear decreases.

[0009] One object of one embodiment of the present invention is to provide a driving device capable of ensuring the lifting amount of a fluid by a gear while suppressing suction of air bubbles by a pump.

[0010] Means for solving problems

[0011] A drive device according to one embodiment of the present invention comprises: a motor having a motor shaft rotatable about a motor axis; a transmission mechanism located on one side of the motor in the axial direction and having a plurality of gears for transmitting the power of the motor; a plurality of bearings supporting the transmission mechanism; a housing provided with a motor chamber for accommodating the motor and a gear chamber for accommodating the transmission mechanism; a flow path for flowing a fluid, at least a portion of which is provided in the housing; and a pump arranged in the flow path and sucking the fluid from an inlet opening in the gear chamber and delivering the fluid under pressure. A partition wall is provided in the gear chamber for dividing the gear chamber into a first area and a second area. A ring gear having the largest diameter among the plurality of gears is arranged in the first area. The inlet is arranged in the second area. The housing has a cylindrical portion for holding the bearing. The flow path comprises a first flow path portion for supplying the fluid to the inner peripheral surface of the cylindrical portion; and a second flow path portion extending from the inner peripheral surface of the cylindrical portion to the opening end located in the first area.

[0012] Effects of the Invention

[0013] According to one aspect of the present invention, it is possible to provide a driving device capable of ensuring the lifting amount of a fluid by a gear while suppressing suction of air bubbles by a pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a conceptual diagram of a driving device according to one embodiment.

[0015] Figure 2 It is a front view of the gear chamber and the partition wall of one embodiment.

[0016] Figure 3 This is a front view of the gear cover according to one embodiment as viewed from the gear chamber side.

[0017] Figure 4 is a schematic diagram of a partition wall according to an embodiment.

[0018] Figure 5 It is a perspective view of a gear cover according to one embodiment.

[0019] Figure 6 This is a perspective view showing a part of the gear cover according to one embodiment.

[0020] Figure 7 It is a schematic diagram of the terminal flow path portion of a modified example. DETAILED DESCRIPTION

[0021] Hereinafter, a drive device according to an embodiment of the present invention will be described with reference to the drawings. In the following description, the vertical direction is defined based on the positional relationship when the drive device 1 according to the present embodiment is mounted on a vehicle (not shown) located on a horizontal road surface.

[0022] In the accompanying drawings, the XYZ coordinate system is appropriately shown as a three-dimensional orthogonal coordinate system. In the XYZ coordinate system, the Z-axis direction is the up-down direction. The up-down direction is, for example, 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 present embodiment, the upper side in the vertical direction is referred to as the "upper side", and the lower side in the vertical direction is referred to as the "lower side". The X-axis direction is a direction perpendicular to the Z-axis direction, and is the front-to-back direction of the vehicle equipped with the drive device 1. 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 perpendicular to both the X-axis direction and the Z-axis direction, and is the left-to-right direction of the vehicle, that is, the vehicle width direction. The Y-axis direction is equivalent to the axial direction of the first axis J1, the second axis J2, and the third axis J3 described later. The front-to-back direction and the left-to-right direction are horizontal directions perpendicular to the vertical direction.

[0023] The first axis J1, the second axis J2, and the third axis J3 appropriately shown in the respective figures are parallel to each other and extend along the Y-axis direction (i.e., the left-right direction of the vehicle, the direction along the horizontal plane). In the present embodiment, unless otherwise specified, the direction parallel to the first axis J1 is referred to as "axial", the radial direction centered on the first axis J1 is referred to as "radial", and the circumferential direction centered on the first axis J1, i.e., the direction around the first axis J1 is referred to as "circumferential". In addition, in the following description, one axial side refers to the +Y side in the direction along the Y-axis, and the other axial side refers to the -Y side in the direction along the Y-axis. In addition, in the present embodiment, "parallel directions" include substantially parallel directions, and "vertical directions" include substantially vertical directions.

[0024] Figure 1 It is a conceptual diagram of the driving device 1 .

[0025] The drive device 1 of this embodiment is mounted on an electric vehicle (EV) and used as its power source. Alternatively, the drive device 1 may be mounted on a vehicle using a motor as a power source, such as a hybrid electric vehicle (HEV) or a plug-in hybrid electric vehicle (PHV).

[0026] like Figure 1As shown, the drive device 1 includes a motor 2, a transmission mechanism 3, a plurality of bearings B1, B2, B3, B4, B5, B6, B7, an inverter 7, a housing 6, a fluid O, a pump 8, and a cooler 9. The motor 2, the transmission mechanism 3, the plurality of bearings B1, B2, B3, B4, B5, B6, B7, and the inverter 7 are accommodated in the housing 6. The plurality of bearings B1, B2, B3, B4, B5, B6, B7 respectively support the transmission mechanism 3 and the rotor 20 of the motor 2. The fluid O is stored in the housing 6. The pump 8 and the cooler 9 are fixed to the outer side surface of the housing 6.

[0027] <Motor>

[0028] The motor 2 of the present embodiment is a three-phase AC motor. The motor 2 has both the function of an electric motor and the function of a generator. The motor 2 is located on the other axial side (-Y side) of the transmission mechanism 3. The motor 2 has a rotor 20 that rotates around a first axis (motor axis) J1 extending in the horizontal direction and a stator 25 located radially outside the rotor 20. The motor 2 of the present embodiment is an inner rotor type motor in which the rotor 20 is arranged on the inner side of the stator 25. The structure of the motor 2 is not limited to the present embodiment.

[0029] The rotor 20 rotates around a first axis J1 extending in the horizontal direction. The rotor 20 includes a motor shaft 21, a rotor core 24 fixed to the outer peripheral surface of the motor shaft 21, and a rotor magnet (not shown) fixed to the rotor core.

[0030] The motor shaft 21 extends axially with the first axis J1 as the center. The motor shaft 21 rotates with the first axis J1 as the center. The end of the motor shaft 21 on one axial side (+Y side) is connected to the first shaft 46 of the transmission mechanism 3. Thus, the torque of the rotor 20 is transmitted to the transmission mechanism 3. The motor shaft 21 is a hollow shaft. A hole extending radially outward from the hollow portion 21h is provided in the motor shaft 21. The motor shaft 21 is rotatably supported by the housing 6 via bearings B5 and B6.

[0031] The stator 25 is held by the housing 6. The stator 25 surrounds the rotor 20 from the radially outer side. The outer peripheral surface of the stator 25 faces the inner peripheral surface of the housing 6. The stator 25 has an annular stator core 27 centered on the first axis J1 and a coil 26 attached to the stator core 27. The stator core 27 is fixed to the housing 6.

[0032] The coil 26 is respectively mounted on each tooth portion of the stator core 27 via an insulator (not shown). The coil 26 is composed of a plurality of coil wires. In addition, the coil 26 can also be composed by connecting a plurality of rod-shaped conductors. The coil 26 has coil ends protruding from both axial ends of the stator core 27. A bus bar 30 is connected to the coil 26. An alternating current is supplied to the coil 26 via the bus bar 30.

[0033] <Transmission mechanism>

[0034] The transmission mechanism 3 is located on one axial side (+Y side) of the motor 2. The transmission mechanism 3 has a plurality of gears 41, 42, 43, 51 for transmitting the power of the motor 2. The transmission mechanism 3 reduces the rotation output from the motor 2 and increases the torque output from the motor 2 and outputs it from the output shaft 55.

[0035] The transmission mechanism 3 includes a first shaft 46, a first gear 41, a second shaft 45, a second gear 42, a third gear 43, a differential device 5, and an output shaft 55. The first shaft 46 and the second shaft 45 are hollow shafts, respectively. The first shaft 46, the second shaft 45, and the output shaft 55 extend parallel to each other.

[0036] The first shaft 46 and the first gear 41 are arranged around the first axis J1. The first shaft 46 extends in the axial direction of the first axis J1. The first shaft 46 is connected to the motor shaft 21 at the end on the other axial side (-Y side). The first gear 41 is provided on the outer peripheral surface of the first shaft 46. The first gear 41 rotates together with the first shaft 46 around the first axis J1. The first shaft 46 is rotatably supported by the housing 6 via bearings B1 and B2.

[0037] The second shaft 45, the second gear 42 and the third gear 43 are arranged around the second axis J2 parallel to the first axis J1. The second shaft 45 extends along the axial direction of the second axis J2. The second shaft 45 is rotatably supported on the housing 6 via bearings B3 and B4. The second gear 42 and the third gear 43 are arranged on the outer peripheral surface of the second shaft 45 at intervals from each other in the axial direction. The second gear 42 and the third gear 43 rotate around the second axis J2 together with the second shaft 45. The second gear 42 meshes with the first gear 41. The third gear 43 meshes with the ring gear 51 of the differential device 5.

[0038] The differential device 5 has a ring gear 51 and a differential mechanism 5a. The differential device 5 meshes with the third gear 43 at the ring gear 51. The ring gear 51 rotates around the third axis J3 parallel to the first axis J1. The ring gear 51 is the gear with the largest diameter among the multiple gears of the transmission mechanism 3. The ring gear 51 is rotatably supported on the housing 6 via a bearing B7. The rotation of the ring gear 51 is transmitted to the differential mechanism 5a, and then output from the output shaft 55 connected to the differential mechanism 5a. When the vehicle turns, the differential mechanism 5a absorbs the speed difference between the left and right wheels while transmitting torque to the output shafts 55 of the left and right wheels. The output shaft 55 extends along the third axis J3. The output shaft 55 is connected to the wheels.

[0039] The torque output from the motor 2 is transmitted to the ring gear 51 of the differential device 5 via the motor shaft 21, the first shaft 46, the first gear 41, the second gear 42, the second shaft 45, and the third gear 43, and further transmitted to the wheels via the differential mechanism 5a and the output shaft 55. In this way, the transmission mechanism 3 transmits the torque of the motor 2 to the wheels of the vehicle.

[0040] <Inverter>

[0041] The inverter 7 converts a direct current supplied from a battery (not shown) into an alternating current. The inverter 7 is connected to the coil 26 of the stator 25 via a bus bar 30. The inverter 7 supplies electric power to the motor 2 via the bus bar 30 to control the motor 2.

[0042] <Housing>

[0043] The housing 6 is provided with a motor chamber 6A for accommodating the motor 2, a gear chamber 6B for accommodating the transmission mechanism 3, and an inverter chamber 6C for accommodating the inverter 7. The gear chamber 6B is located on one axial side (+Y side) of the motor chamber 6A. In addition, the inverter chamber 6C is located on the upper side (+Z side) of the motor chamber 6A.

[0044] The housing 6 stores a fluid O. The housing 6 is provided with a flow path 90. The fluid O circulates in the housing 6 through the flow path 90. The fluid O functions as a refrigerant for cooling the motor 2 and as a lubricant for the transmission mechanism 3. As the fluid O, in order to function as a lubricating oil and a cooling oil, it is preferable to use an oil equivalent to an automatic transmission lubricating oil (ATF: Automatic Transmission Fluid) having a relatively low viscosity.

[0045] The fluid O is stored in the lower region of the internal space of the housing 6. That is, the fluid O is stored in the lower region of the housing 6. Hereinafter, the region in the lower region of the housing 6 where the fluid O is stored is referred to as a storage portion P. In the housing 6 of the present embodiment, the bottom surface of the motor chamber 6A and the bottom surface of the gear chamber 6B are substantially aligned in the vertical direction. Therefore, the storage portion P is provided across the lower region of the motor chamber 6A and the lower region of the housing 6.

[0046] The ring gear 51 is immersed in the fluid O in the reservoir P. The ring gear 51 lifts the fluid O in the reservoir P and spreads it into the gear chamber 6B as it rotates about the third axis J3. The fluid O lifted by the ring gear 51 is supplied to each gear in the gear chamber 6B and is used to lubricate the gear tooth surfaces.

[0047] The fluid O in the reservoir P is delivered to the upper region of the motor chamber 6A and the upper region of the gear chamber 6B through the flow path 90. The fluid O delivered to the upper region of the motor chamber 6A cools the motor 2 along the surface of the motor 2, and then drips to the reservoir P in the lower region of the motor chamber 6A. The fluid O delivered to the upper region of the gear chamber 6B lubricates the gears of the transmission mechanism 3 and the bearings supporting the transmission mechanism 3, and then drips to the reservoir P in the lower region of the gear chamber 6B.

[0048] The housing 6 is formed by combining a plurality of components. The housing 6 includes: a housing body (first component) 61; a motor cover 63, which is located on the other axial side (-Y side) of the housing body 61; a gear cover (second component) 62, which is located on one axial side (+Y side) of the housing body 61; and an inverter cover 64, which is located on the upper side (+Z side) of the housing body 61. The housing body 61 and the motor cover 63 are connected in the axial direction to form a motor chamber 6A. The housing body 61 and the gear cover 62 are connected in the axial direction to form a gear chamber 6B. The housing body 61 and the inverter cover 64 are connected in the substantially vertical direction to form an inverter chamber 6C.

[0049] The housing body 61 has a partition wall 65 that partitions the motor chamber 6A and the gear chamber 6B. The partition wall 65 extends along a plane perpendicular to the first axis J1. The partition wall 65 supports the shafts of the motor 2 and the transmission mechanism 3 via bearings.

[0050] The partition wall 65 is provided with a pump communication hole 65a, a partition wall opening 65b, and a shaft insertion hole 65c. The pump communication hole 65a, the partition wall opening 65b, and the shaft insertion hole 65c penetrate the partition wall 65. The pump communication hole 65a, the partition wall opening 65b, and the shaft insertion hole 65c connect the motor chamber 6A and the gear chamber 6B so that they communicate with each other.

[0051] The shaft insertion hole 65c is substantially circular with the first axis J1 as the center when viewed from the axial direction. The shaft insertion hole 65c is provided with a bearing B5 for holding the motor shaft 21 and a bearing B2 for holding the first shaft 46. The motor shaft 21 and the first shaft 46 are connected to each other inside the shaft insertion hole 65c.

[0052] Figure 2 It is a front view of the gear chamber 6B and the partition wall 65 .

[0053] like Figure 2 As shown, the partition wall opening 65b and the pump communication hole 65a are arranged at the lower end of the partition wall 65. Figure 1 The positional relationship between the partition wall opening 65b and the pump communication hole 65a shown is schematic and does not represent the actual position. Figure 2 As shown, the actual partition wall opening 65b and the pump communication hole 65a are arranged side by side on the upper side of the bottom surface of the gear chamber 6B.

[0054] like Figure 1 As shown, the pump communication hole 65a opens in the motor chamber 6A and the gear chamber 6B. A merging flow path 91a opens in the path of the pump communication hole 65a. The merging flow path 91a is connected to the suction port 8c of the pump 8.

[0055] like Figure 2 As shown, the end of the upstream side of the confluent flow path portion 91a is opened across the side and bottom of the pump communication hole 65a. The pump 8 of this embodiment is arranged on the rear side (-X side) of the vehicle relative to the pump communication hole 65a. The confluent flow path portion 91a extends in the front-to-back direction. The confluent flow path portion 91a is gently inclined toward the upper side (+Z side) as it moves toward the rear side (-X side) of the vehicle between the pump communication hole 65a and the suction port 8c of the pump.

[0056] like Figure 1 As shown, the area of ​​the pump communication hole 65a that is closer to the gear chamber 6B than the opening of the merging flow path portion 91a constitutes the first branch flow path portion 91b. In addition, the area of ​​the pump communication hole 65a that is closer to the motor chamber 6A than the opening of the merging flow path portion 91a constitutes the second branch flow path portion 91c. The first branch flow path portion 91b opens in the gear chamber 6B, and the second branch flow path portion 91c opens in the motor chamber 6A. The first branch flow path portion 91b, the second branch flow path portion 91c, and the merging flow path portion 91a constitute the suction flow path portion 91.

[0057] Here, the opening of the first branch flow path portion 91b to the gear chamber 6B is referred to as the first inlet (inlet) 91p, and the opening of the second branch flow path portion 91c to the motor chamber 6A is referred to as the second inlet 91q. The fluid O in the gear chamber 6B flows into the suction flow path portion 91 from the first inlet 91p. On the other hand, the fluid O in the motor chamber 6A flows into the suction flow path portion 91 from the second inlet 91q. The fluid O flowing in from the gear chamber 6B and the motor chamber 6A respectively merges in the pump connecting hole 65a and is sucked into the pump 8 through the merged flow path portion 91a. According to the present embodiment, the pump 8 can suck in the fluid O from either the motor chamber 6A or the gear chamber 6B via the first branch flow path portion 91b and the second branch flow path portion 91c.

[0058] Here, in the case of a structure in which the suction flow path portion connected to the pump is opened only in the gear chamber, in order to guide the fluid to the gear chamber, the gear chamber may be arranged at a position lower than the motor chamber, etc., resulting in restrictions on the structure of the housing. In contrast, according to the present embodiment, the pump 8 sucks the fluid O from either the gear chamber 6B or the motor chamber 6A, so the degree of freedom of the structure of the housing 6 can be increased to achieve miniaturization of the drive device 1. In particular, when the bottom surfaces of the motor chamber 6A and the gear chamber 6B are set to be substantially the same height in the vertical direction as in the present embodiment, the projection area of ​​the motor chamber 6A projected onto the gear chamber 6B in the axial direction can be expanded, and the size of the drive device 1 viewed from the axial direction can be miniaturized.

[0059] Figure 3 This is a front view of the gear cover 62 as seen from the gear chamber 6B side.

[0060] The gear cover 62 has a side wall portion 62w covering the gear chamber 6B from one axial side (+Y side). That is, the housing 6 has the side wall portion 62w. The side wall portion 62w extends along a plane (XZ plane) perpendicular to the axial direction.

[0061] The side wall portion 62w is provided with a first cylindrical portion 62a, a second cylindrical portion 62b, and a third cylindrical portion 62c. That is, the housing 6 has the first cylindrical portion 62a, the second cylindrical portion 62b, and the third cylindrical portion 62c. The first cylindrical portion 62a, the second cylindrical portion 62b, and the third cylindrical portion 62c protrude from the surface of the side wall portion 62w facing the other axial side (-Y side) toward the other axial side.

[0062] The first cylindrical portion 62a is cylindrical with the first axis J1 as the center. The first cylindrical portion 62a holds the bearing B1. The first cylindrical portion 62a supports the first shaft 46 rotatably via the bearing B1. The second cylindrical portion 62b is cylindrical with the second axis J2 as the center. The second cylindrical portion 62b holds the bearing B3. The second cylindrical portion 62b supports the second shaft 45 rotatably via the bearing B3. The outer side surface of the second cylindrical portion 62b is connected to the outer side surface of the first cylindrical portion 62a. The third cylindrical portion 62c is cylindrical with the third axis J3 as the center. The third cylindrical portion 62c holds the bearing B7. The third cylindrical portion 62c supports the ring gear 51 rotatably via the bearing B7.

[0063] like Figure 2 and Figure 3 As shown in FIG. 1 , the gear chamber 6B is provided with a partition wall 67 extending in a curved manner along the tooth top of the ring gear 51. The partition wall 67 is composed of a first portion 67P ( Figure 2 ) and the second portion 67Q ( Figure 3) are connected. The partition wall 67 extends in a substantially circular arc shape with the third axis J3 as the center. The partition wall 67 is curved along the tooth top of the ring gear 51. The partition wall 67 guides the fluid O in the storage portion P along the tooth top of the ring gear 51 in the circumferential direction around the third axis J3 through the surface of the third axis J3 facing the radial inner side. The ring gear 51 can effectively lift the fluid O through the partition wall 67.

[0064] like Figure 2 As shown, the partition wall 67 is located between the first inlet 91p and the ring gear 51. The partition wall 67 divides the gear chamber 6B into a first area A1 where the ring gear 51 is arranged and a second area A2 where the first inlet 91p is arranged. According to the present embodiment, it is possible to suppress the bubbles generated by the stirring of the fluid O by the ring gear 51 from invading the suction flow path portion 91 through the first inlet 91p. Thus, it is possible to suppress the bubbles from invading the suction port 8c of the pump 8, and it is possible to suppress the reduction in the pressure delivery efficiency of the pump 8 caused by the suction of the bubbles.

[0065] In the present specification, the first area A1 and the second area A2 are areas partitioned by the partition wall 67 in the gear chamber 6B, and are located below the upper end of the partition wall 67 in the gear chamber 6B.

[0066] In the present embodiment, the inlet (first inlet 91p) disposed in the second area A2 is a part of the housing 6. However, the inlet may be any other structure as long as it is an inlet portion of the gear chamber 6B opening for the fluid O to flow in and guide the fluid O into the pump 8. As an example, the inlet may be a suction port of the pump 8 that is directly opened in the gear chamber 6B. In addition, the inlet (first inlet 91p) may not be disposed on the upper side of the bottom surface of the gear chamber 6B. For example, the inlet (first inlet 91p) may also be disposed on the bottom surface of the gear chamber 6B.

[0067] In this embodiment, the partition wall 67 is described as being curved along the tooth top of the ring gear 51. However, as long as the partition wall 67 is located between the first inlet 91p and the ring gear 51, it can suppress the inflow of bubbles into the first inlet 91p, and its structure is not limited to this embodiment.

[0068] like Figure 3 As shown, a first communicating hole 67a and a second communicating hole 67b are provided on the partition wall 67. The communicating hole 67a and the second communicating hole 67b penetrate the partition wall 67 in the thickness direction. The first communicating hole 67a is located at the lower end of the partition wall 67. On the other hand, the second communicating hole 67b is located above the first communicating hole 67a.

[0069] By providing the partition wall 67 in the gear chamber 6B, the fluid O accumulated in the second area A2 is not easy to flow freely into the periphery of the ring gear 51 (the first area A1). Therefore, the fluid O that moves to the second area A2 due to the lifting of the fluid O in the first area A1 by the ring gear 51 is not easy to flow into the first area A1. By lifting the fluid O in the first area A1 by the ring gear 51, the liquid level of the fluid O in the first area A1 is lowered, so the lifting amount of the fluid O by the ring gear 51 is reduced, and the supply of the fluid O to each gear in the gear chamber 6B may be insufficient. According to the present embodiment, by providing the first connecting hole 67a and the second connecting hole 67b in the partition wall 67, the fluid O can be guided from the second area A2 to the first area A1, thereby suppressing the reduction in the lifting amount of the fluid O by the ring gear 51. In addition, this effect can be obtained as long as at least one connecting hole (the first connecting hole 67a or the second connecting hole 67b) is provided in the partition wall 67. That is, it is sufficient that at least one of the first communication hole 67 a and the second communication hole 67 b is provided in the partition wall 67 , and a plurality of communication holes may be provided.

[0070] According to the present embodiment, by providing the first connecting hole 67a at the lower end of the partition wall 67, the fluid O can be moved from the second area A2 to the first area A1 regardless of the height of the liquid level in the second area A2, and the shortage of the fluid O in the first area A1 can be supplemented from the second area A2. In addition, the dividing wall 67 of the present embodiment extends in a substantially circular arc shape along the tooth top of the ring gear 51. Thus, the dividing wall 67 can make it easy for the fluid O in the first area A1 to flow along the rotation direction of the ring gear 51 together with the ring gear 51. If the cross-sectional area of ​​the first connecting hole 67a provided at the lower end of the dividing wall 67 is too large, the fluid flowing along the rotation direction of the ring gear 51 together with the ring gear 51 in the first area A1 flows into the second area A2 through the first connecting hole 67a, and the fluid O may not be sufficiently lifted. According to the present embodiment, by providing a plurality of communicating holes (the first communicating hole 67a and the second communicating hole 67b), even if the cross-sectional area of ​​each communicating hole is reduced, the supply amount of the fluid O from the second area A2 to the first area A1 can be ensured, the lifting of the fluid O by the ring gear 51 can be appropriately performed, and the reduction in the liquid level of the fluid O in the first area A1 can be suppressed. In addition, in the present embodiment, the cross-sectional area of ​​the second communicating hole 67b is larger than the cross-sectional area of ​​the first communicating hole 67a. Therefore, by suppressing the movement of the fluid O from the first area A1 to the second area A2 via the first communicating hole 67a, the reduction in the liquid level of the fluid O in the first area A1 is suppressed, and when the liquid level of the fluid O in the second area A2 is increased, the movement amount of the fluid O from the second area A2 to the first area A1 via the second communicating hole 67b can be ensured. In addition, the “cross-sectional area” of the first communication hole 67 a and the second communication hole 67 b refers to the flow path cross-sectional area in the cross-sectional area intersecting the flow direction of the fluid O passing through the first communication hole 67 a and the second communication hole 67 b .

[0071] Figure 4 Schematic diagram of the partition wall 67 .

[0072] The partition wall 67 is formed by the first part 67P which is a part of the housing body 61 and the second part 67Q which is a part of the gear cover 62 being butted in the axial direction. The end surface of the second part 67Q which faces the other axial side (-Y side) is provided with notches 67c and 67e. The end surface of the first part 67P which faces the one axial side (+Y side) covers the openings of the notches 67c and 67e. The first connecting hole 67a is provided in the area surrounded by the inner edge of the notch 67e and the end surface of the first part 67P. The second connecting hole 67b is provided in the area surrounded by the inner edge of the notch 67c and the end surface of the first part 67P. That is, the first connecting hole 67a and the second connecting hole 67b are formed by combining the first part 67P which is provided with the notches 67c and 67e and the second part 67Q which is not provided with the notches.

[0073] According to the present embodiment, the first communication hole 67a and the second communication hole 67b can be formed on the partition wall 67 without performing post-processing such as drilling, thereby reducing the manufacturing cost of the drive device 1. In addition, compared with the case where the first communication hole 67a and the second communication hole 67b are formed by drilling, the degree of freedom of the shape and position of the first communication hole 67a and the second communication hole 67b can be increased, and the first communication hole 67a and the second communication hole 67b of a more preferred size can be formed at a more preferred position.

[0074] like Figure 1 As shown, in the transmission mechanism 3, the third gear 43 and the ring gear 51 that mesh with each other are arranged at a position closer to the partition wall 65 than the first gear 41 and the second gear 42 that mesh with each other. The gear with the largest diameter among the plurality of gears of the transmission mechanism 3 is the ring gear 51. By arranging the ring gear 51 close to the partition wall 65, the area that overlaps with the ring gear 51 in the axial direction in the gear chamber 6B can be miniaturized in the axial direction, and the miniaturization of the drive device 1 can be achieved.

[0075] The plurality of gears of the transmission mechanism 3 are classified into the ring gear 51 and the other transmission gears 41, 42, 43. That is, the plurality of gears 41, 42, 43, 51 of the transmission mechanism 3 have the ring gear 51 and the transmission gears 41, 42, 43 that transmit power to the ring gear 51. The side wall portion 62w of the gear cover 62 has a first side wall area 62A that overlaps with the transmission gears 41, 42, 43 when viewed axially, and a second side wall area 62B that overlaps with the ring gear 51 when viewed axially. In addition, the second side wall area 62B is located outside the first side wall area 62A, and is an area that overlaps only with the ring gear 51. When viewed axially, the area of ​​the side wall portion 62w that overlaps with the ring gear 51 and any transmission gear is not included in the second side wall area 62B, but is included in the first side wall area 62A. In addition, Figure 1 This is a diagram schematically showing the state of the transmission mechanism 3 , and shows that a part of the parts overlapping in the vehicle front-rear direction rather than in the axial direction overlap in the axial direction.

[0076] Figure 5 It is a perspective view of the gear cover 62 .

[0077] like Figure 5 As shown, the second side wall region 62B is located at a position closer to the other axial side (-Y side) than the first side wall region 62A. According to the present embodiment, by arranging the ring gear 51 having the largest diameter closer to the side of the partition wall 65, the second side wall region 62B overlapping with the ring gear 51 can be arranged at a position closer to the side of the partition wall 65 than the first side wall region 62A. Thus, the housing 6 can be made small. Furthermore, by arranging the second side wall region 62B closer to the partition wall 65, the axial dimension of the gear chamber 6B around the ring gear 51 can be reduced. Thus, the liquid level of the fluid O accumulated in the first region A1 of the gear chamber 6B can be kept high, and the lifting efficiency of the ring gear 51 can be improved.

[0078] <Flow path>

[0079] Figure 1 The flow path 90 shown is a circulation path for the fluid O to flow. That is, the fluid O flows in the flow path 90 provided in the housing 6. It is sufficient that at least a portion of the flow path 90 is provided in the housing 6. The flow path 90 is a path for the fluid O to be supplied from the storage portion P to the motor 2 and the transmission mechanism 3. In addition, in this specification, the "flow path" is a concept that includes not only a path for forming a stable flow of the fluid O in one direction, but also a path for temporarily retaining the fluid O and a path for the fluid O to drip.

[0080] The pump 8, the cooler 9, the first supply pipe (first supply unit) 93A, the second supply pipe (second supply unit) 95A, and the third supply pipe 94A are arranged in the flow path 90. The first supply pipe 93A, the second supply pipe 95A, and the third supply pipe 94A are arranged inside the housing 6.

[0081] The pump 8 sucks the fluid O from the first inlet 91p opened in the gear chamber 6B and the second inlet 91q opened in the motor chamber 6A and pressure-feeds the fluid O. Thus, the pump 8 supplies the fluid O to the motor 2 and the transmission mechanism 3. The pump 8 of this embodiment is an electric pump driven by electricity.

[0082] The cooler 9 cools the fluid O in the flow path 90. A refrigerant (not shown) flows inside the cooler 9. The cooler 9 is a heat exchanger that transfers heat of the fluid O to the refrigerant.

[0083] The first supply pipe 93A and the second supply pipe 95A are arranged in the motor chamber 6A. The first supply pipe 93A and the second supply pipe 95A extend in the axial direction respectively. The ends of the first supply pipe 93A and the second supply pipe 95A on one axial side (+Y side) are supported by the partition wall 65, and the ends on the other axial side (-Y side) are supported by the motor cover 63. The first supply pipe 93A and the second supply pipe 95A are provided with a plurality of injection holes opening toward the stator 25. The first supply pipe 93A and the second supply pipe 95A are both arranged on the upper side of the motor 2. In addition, Figure 1 In FIG. 1 , the second supply pipe 95A is shown on the lower side of the motor 2 , but this is a schematic illustration and does not represent the actual structure.

[0084] The third supply pipe 94A is arranged in the gear chamber 6B. The third supply pipe 94A extends in the axial direction. The end of the third supply pipe 94A on one axial side (+Y side) is supported by the gear cover 62, and the end of the third supply pipe 94A on the other axial side (-Y side) is supported by the partition wall 65. The third supply pipe 94A of this embodiment is arranged coaxially with the first supply pipe 93A. A plurality of injection holes opening toward the transmission mechanism 3 are provided in the third supply pipe 94A.

[0085] The flow path 90 of this embodiment includes a suction flow path portion 91, a first pressure-feeding flow path portion 91A, a second pressure-feeding flow path portion 92, a third pressure-feeding flow path portion 93, a fourth pressure-feeding flow path portion 94, a fifth pressure-feeding flow path portion 95, a lubrication supply flow path portion (first flow path portion) 96, and a terminal flow path portion (second flow path portion) 99. The third pressure-feeding flow path portion 93, the fourth pressure-feeding flow path portion 94, and the fifth pressure-feeding flow path portion 95 are flow paths passing through the interior of the first supply pipe 93A, the second supply pipe 95A, and the third supply pipe 94A, respectively.

[0086] The suction flow path portion 91 is a flow path connecting the reservoir P and the pump 8. The suction flow path portion 91 includes a first branching flow path portion 91b, a second branching flow path portion 91c, and a merging flow path portion 91a.

[0087] The first pressure-feeding flow path portion 91A extends from the pump 8 to the motor cover 63. The cooler 9 is disposed in the path of the first pressure-feeding flow path portion 91A.

[0088] The second pressure-feeding flow path section 92 is provided in the motor cover 63. The second pressure-feeding flow path section 92 is connected to the first pressure-feeding flow path section 91A at the end on the upstream side. The second pressure-feeding flow path section 92 branches into three flow paths in the middle, and is connected to the second supply pipe 95A at the first branch flow path, connected to the hollow portion 21h of the motor shaft 21 at the second branch flow path, and connected to the first supply pipe 93A at the third branch flow path. Part of the fluid O that flows into the second pressure-feeding flow path section 92 flows into the second supply pipe 95A, the hollow portion 21h, and the first supply pipe 93A, respectively.

[0089] The fluid O supplied to the second supply pipe 95A flows in the fifth pressure-feeding flow path 95 provided inside the second supply pipe 95A. The fluid O flowing into the fifth pressure-feeding flow path 95 is supplied to the motor 2 via the discharge hole provided in the second supply pipe 95A.

[0090] A portion of the fluid O supplied to the hollow portion 21h of the motor shaft 21 is supplied to the bearing B6 supporting the motor shaft 21 to lubricate the bearing, and after passing through a hole provided in the motor shaft 21 and connected to the hollow portion 21h, the fluid O is scattered radially outward from the rotor 20 due to centrifugal force and supplied to the stator 25 .

[0091] The fluid O supplied to the first supply pipe 93A flows in the third pressure-feeding flow path portion 93 provided inside the first supply pipe 93A. A portion of the fluid O flowing in the third pressure-feeding flow path portion 93 is supplied to the motor 2 via the ejection hole provided in the first supply pipe 93A. The downstream end of the third pressure-feeding flow path portion 93 is connected to the fourth pressure-feeding flow path portion 94.

[0092] The fourth pressure-feeding flow path 94 is provided inside the third supply pipe 94A. A part of the fluid O flowing into the fourth pressure-feeding flow path 94 is supplied to the transmission mechanism 3 via the discharge hole provided in the third supply pipe 94A. The downstream end of the fourth pressure-feeding flow path 94 is connected to the lubrication supply flow path 96.

[0093] The lubrication supply flow path portion 96 is provided in the gear cover 62. The lubrication supply flow path portion 96 supplies the fluid O to the inner peripheral surface of the second cylindrical portion 62b and the inner peripheral surface of the first cylindrical portion 62a. The fluid O flowing into the lubrication supply flow path portion 96 is supplied to the bearing B3 supporting the second shaft 45 and the bearing B1 supporting the first shaft 46. The lubrication supply flow path portion 96 includes a first supply portion 96a and a second supply portion 96b.

[0094] like Figure 3As shown in FIG. 1 , a support hole 62h for inserting the third supply pipe 94A is provided in the side wall portion 62w of the gear cover 62. The first supply portion 96a is a groove provided on the surface of the side wall portion 62w of the gear cover 62 that faces the other axial side (-Y side). The first supply portion 96a extends from the support hole 62h to the inner side of the second cylindrical portion 62b. The fluid O flowing out from the end of the third supply pipe 94A reaches the inner side of the second cylindrical portion 62b through the first supply portion 96a, and lubricates the bearing B3.

[0095] The second supply portion 96b is a hole portion connecting the inner side surface of the second cylindrical portion 62b and the inner side surface of the first cylindrical portion 62a. The opening of the inner side surface of the second cylindrical portion 62b of the second supply portion 96b is located at the lower end of the inner side surface of the second cylindrical portion 62b. Therefore, the fluid O accumulated inside the second cylindrical portion 62b is naturally guided to the second supply portion 96b. The fluid O inside the second cylindrical portion 62b reaches the inner side of the first cylindrical portion 62a through the second supply portion 96b, and lubricates the bearing B1.

[0096] The terminal flow path portion 99 is a hole portion provided in the side wall portion 62w. The terminal flow path portion 99 connects the inner side surface of the first cylindrical portion 62a and the first area A1 of the gear chamber 6B. The opening of the inner side surface of the first cylindrical portion 62a of the terminal flow path portion 99 is located at the lower end of the inner side surface of the first cylindrical portion 62a. Therefore, the fluid O accumulated inside the first cylindrical portion 62a is guided to the terminal flow path portion 99.

[0097] The terminal flow path portion 99 has an opening end 99a that opens in the first area A1. The opening end 99a is located in the first area A1. That is, the terminal flow path portion 99 extends from the inner peripheral surface of the first cylindrical portion 62a to the opening end 99a located in the first area A1. The fluid O inside the first cylindrical portion 62a passes through the terminal flow path portion 99 and reaches the first area A1.

[0098] As described above, the fluid O in the first area A1 is lifted by the ring gear 51, and the liquid level of the fluid O in the first area A1 is reduced. As a result, the amount of fluid O lifted by the ring gear 51 is reduced, and the supply of fluid O to each gear in the gear chamber 6B may be insufficient. According to the present embodiment, the flow path 90 has the terminal flow path portion 99, and thus the fluid O stored in the area opposite to the first area A1 across the partition wall 67 can be guided to the first area A1. As a result, the liquid level of the first area A1 can be suppressed from being lowered, and the insufficient supply of fluid O to each gear caused by the lifting of the ring gear 51 can be suppressed.

[0099] In the present embodiment, the first tubular portion 62a is arranged on the upper side of the second area A2, so when the fluid O overflows from the first tubular portion 62a, the overflowed fluid O flows into the second area A2. According to the present embodiment, by connecting the terminal flow path portion 99 to the first tubular portion 62a, the fluid O that overflows from the first tubular portion 62a and should flow into the second area A2 can be provided to the first area A1. The first tubular portion 62a only needs to be arranged in the second area A2 or on the upper side of the second area A2. In addition, the first tubular portion 62a is not only arranged in the second area A2 or on the upper side of the second area A2 as a whole, but also can be arranged in a part of the second area A2 at least in part.

[0100] In addition, the cylindrical portion (first cylindrical portion 62a) connected to the flow path portion (terminal flow path portion 99) is not limited to the above-mentioned configuration, and may be configured in the first region A1 or above the first region A1. In this case, the flow path portion can also stably transport the fluid O from the cylindrical portion to the first region A1, and the liquid level in the first region A1 can be quickly increased compared to the case where the fluid overflowing from the cylindrical portion flows into the first region A1.

[0101] As described above, when the fluid O in the first area A1 is insufficient, the fluid O is supplied from the second area A2 to the first area A1 via the first communicating hole 67a and the second communicating hole 67b provided in the partition wall 67. However, it is assumed that the fluid O cannot be fully moved via the first communicating hole 67a and the second communicating hole 67b when the vehicle equipped with the drive device 1 is tilted. According to the present embodiment, the fluid O stored in an area different from the first area A1 (the second area A2 and the motor chamber 6A in the present embodiment) is supplied to the first area A1 via the flow path 90, whereby the supply amount of the fluid O to the first area A1 is not easily affected by the tilt of the vehicle, and the fluid O can be stably supplied to the first area A1.

[0102] The first cylindrical portion 62a and the second cylindrical portion 62b are arranged on the upstream side of the terminal flow path portion 99 of the present embodiment. Therefore, the fluid O supplied to the first area A1 is the fluid O remaining after lubricating the bearings B1 and B3. According to the flow path 90 of the present embodiment, the lubrication of the bearings B1 and B3 can be prioritized over the supply of the fluid O to the first area A1, and the seizure of the bearings B1 and B3 can be effectively suppressed.

[0103] The fluid O in the flow path 90 of the present embodiment is pumped by the pump 8. The pump 8 of the present embodiment is an electrically controlled electric pump. Therefore, compared with the case where the pump 8 is a mechanical pump driven in conjunction with the movement of the transmission mechanism 3, the fluid O can be stably supplied to the first area A1 regardless of the driving state of the transmission mechanism 3. Specifically, for example, when going uphill, even if the vehicle equipped with the drive device 1 is tilted and the rotation speed of the transmission mechanism 3 slows down, the fluid O stored in a region different from the first area A1 can be stably supplied to the first area A1, and the liquid level of the fluid O in the first area A1 can be suppressed from decreasing.

[0104] The opening end 99a of the terminal flow path portion 99 of the present embodiment is preferably located at a position lower than the upper end of the second communicating hole 67b. If the opening end 99a is arranged at a position higher than the upper end of the second communicating hole 67b, when the liquid level in the first area A1 is lower than the second communicating hole 67b, the fluid O discharged from the opening end 99a may flow directly from the second communicating hole 67b to the second area A2 along the surface of the partition wall 67. In this case, the fluid O discharged from the terminal flow path portion 99 is not supplied to the first area A1, so the liquid level of the fluid O in the first area A1 can be increased. According to this embodiment, by configuring the opening end 99a at a position lower than the upper end of the second connecting hole 67b, the fluid O discharged from the opening end 99a can be used to increase the liquid level in the first area A1, and the ring gear 51 can effectively lift the fluid O. Here, when the vehicle equipped with the drive device is parked on a horizontal surface, the opening end 99a only needs to be located at a position lower than the upper end of the second connecting hole 67b.

[0105] In addition, the opening end 99a only needs to be arranged at a position lower than the upper end of the uppermost communicating hole 67b arranged in the at least one communicating hole 67a and 67b provided in the partition wall 67. The communicating hole 67b arranged in the uppermost side is easy to be arranged in a position higher than the liquid surface of the first area A1, so when the opening end 99a is arranged at a position higher than the communicating hole 67b, the fluid O discharged from the opening end 99a is easy to flow directly to the second area A2. Here, the "at least one communicating hole arranged in the uppermost side" refers to the one communicating hole arranged in the uppermost side among all the communicating holes when there are multiple communicating holes provided in the partition wall 67, and refers to the communicating hole when there is only one communicating hole provided in the partition wall 67.

[0106] Figure 7The open end 199a of the terminal flow path portion 199 of a modified example that can be adopted in the present embodiment is shown. The open end 199a of the present modified example is located at a position lower than the lower end of the connecting hole 167b arranged at the uppermost side. Since the fluid O discharged from the open end 199a flows downward, by arranging the open end 199a at a position lower than the lower end of the connecting hole 167b, it is possible to further suppress the fluid O from flowing directly from the connecting hole 167b to the second area A2. According to the present modified example, the liquid level of the first area A1 can be increased by the fluid O discharged from the open end 199a. That is, the open end 199a is preferably located at a position lower than the lower end of the connecting hole 167b arranged at the uppermost side among at least one of the connecting holes 167a and 167b.

[0107] like Figure 4 As shown, the first connecting hole 67a and the second connecting hole 67b of the present embodiment are provided on the boundary BL between the first part 67P of the housing body 61 and the second part 67Q of the gear cover 62 which are butted against each other. In addition, here, the boundary BL refers to the contact surface where the first part 67P and the second part 67Q are butted against each other and the extended surface thereof.

[0108] In the present embodiment, the first communicating hole 67a and the second communicating hole 67b are respectively provided in the area surrounded by the notch portions 67c, 67e of the second portion 67Q and the end surface of the first portion 67P. Therefore, the area of ​​the flow path cross section of the first communicating hole 67a on the second portion 67Q side (+Y side) relative to the boundary BL is larger than the area on the first portion 67P side (-Y side) relative to the boundary BL. Similarly, the area of ​​the flow path cross section of the second communicating hole 67b on the second portion 67Q side (+Y side) relative to the boundary BL is larger than the area on the first portion 67P side (-Y side) relative to the boundary BL.

[0109] In the present embodiment, the first inlet 91p is provided in the housing body 61. The first inlet 91p guides the fluid O from the gear chamber 6B to the pump 8. The first communicating hole 67a and the second communicating hole 67b can serve as passages for bubbles accompanying the stirring of the gear ring 51. By making the first communicating hole 67a and the second communicating hole 67b as far away from the first inlet 91p as possible, bubbles passing through the first communicating hole 67a and the second communicating hole 67b are unlikely to reach the first inlet 91p. According to the present embodiment, by arranging the first communicating hole 67a and the second communicating hole 67b to be biased toward the second portion 67Q side relative to the boundary BL, the first communicating hole 67a and the second communicating hole 67b can be made away from the first inlet 91p, and the suction of bubbles into the pump 8 can be suppressed.

[0110] In this embodiment, the case where the notches 67c and 67e constituting the communicating holes 67a and 67b are provided only on the second portion 67Q side is described. Figure 4 As shown by the dotted line in the middle, the communicating holes 67a and 67b may be formed by combining the notches 67d and 67f of the first part 67P and the notches 67c and 67e of the second part 67Q in a face-to-face manner. In this case, by making the area of ​​the notch 67e of the second part 67Q larger than the area of ​​the notch 67f of the first part 67P, the first communicating hole 67a can be arranged to be offset to the second part 67Q side from the boundary BL. Similarly, by making the area of ​​the notch 67c of the second part 67Q larger than the area of ​​the notch 67d of the first part 67P, the second communicating hole 67b can be arranged to be offset to the second part 67Q side from the boundary BL.

[0111] Figure 6 This is a perspective view of the gear cover 62 as viewed from the gear chamber 6B side.

[0112] like Figure 6 As shown, a plurality of ribs 62r are provided on the side wall portion 62w of the gear cover 62. The plurality of ribs 62r are provided on the surface of the side wall portion 62w facing the gear chamber 6B side, and protrude toward the gear chamber 6B side. That is, at least one rib 62r is provided on the inner side surface of the gear chamber 6B. In the present embodiment, the plurality of ribs 62r are arranged in a lattice shape. According to the present embodiment, by providing the ribs 62r on the side wall portion 62w, the housing 6 can be strengthened.

[0113] The opening end 99a of this embodiment is located on the side surface 62s of one rib 62r. ​​Here, the side surface 62s of the rib 62r is one of a pair of surfaces facing in directions substantially perpendicular to the protruding direction of the rib 62r and the extending direction of the rib 62r.

[0114] According to the present embodiment, by arranging the opening end 99a on the side surface 62s of the rib 62r, the opening direction of the opening end 99a can be directed to the side opposite to the partition wall 67. Thus, it is possible to prevent the fluid O discharged from the opening end 99a from directly flowing into the communicating holes 67a and 67b of the partition wall 67 and flowing out to the second area A2. Furthermore, by providing the opening end 99a on the side surface 62s of the rib 62r, when a drill is inserted from the opening end 99a side to form the terminal flow path portion 99, the tip of the drill is easily stabilized, and drilling can be performed stably.

[0115] The various embodiments of the present invention have been described above, but each structure in each embodiment and their combination are examples, and addition, omission, substitution and other changes of the structure can be made without departing from the scope of the gist of the present invention. In addition, the present invention is not limited by the embodiments.

[0116] The structure of each shaft of the transmission mechanism in the above embodiment is an example. The shafts constituting the transmission mechanism are not limited to three. In addition, two of the plurality of shafts may be coaxially arranged in a manner such that one passes through the hollow portion of the other.

[0117] In the present embodiment, the first supply portion 96a connects the support hole 62h and the inner side of the second cylindrical portion 62b, but the support hole 62h and the inner side of the first cylindrical portion 62a may be connected. In addition, in the present embodiment, the terminal flow path portion 99 connects the inner side surface of the first cylindrical portion 62a and the first area A1, but the second cylindrical portion 62b and the first area A1 may be connected. The fluid O stored in the housing 6 is not particularly limited and may be a fluid other than oil. The fluid supplied to the motor by the fluid supply portion may be, for example, water.

[0118] In addition, the present technology can adopt the following structures.

[0119] (1) A drive device, comprising: a motor having a motor shaft rotatable about a motor axis; a transmission mechanism located on one side of the motor in an axial direction and having a plurality of gears for transmitting power of the motor; a plurality of bearings for supporting the transmission mechanism; a housing having a motor chamber for accommodating the motor and a gear chamber for accommodating the transmission mechanism; a flow path for allowing a fluid to flow, at least a portion of which is provided in the housing; and a pump disposed in the flow path for sucking in the fluid from an inlet opening in the gear chamber and for pressure-feeding the fluid, wherein the gear chamber is provided with a partition wall for dividing the gear chamber into a first area and a second area, wherein a ring gear having the largest diameter among the plurality of gears is disposed in the first area, and the inlet is disposed in the second area, wherein the housing has a cylindrical portion for holding the bearings, and wherein the flow path has a first flow path portion for supplying the fluid to an inner peripheral surface of the cylindrical portion; and a second flow path portion extending from the inner peripheral surface of the cylindrical portion to an opening end located in the first area.

[0120] (2) The driving device according to (1), wherein the tubular portion is arranged in the second region or above the second region.

[0121] (3) The driving device according to (1) or (2), wherein at least one communication hole connecting the first area and the second area is provided on the partition wall.

[0122] (4) The driving device according to (3), wherein the opening end is located below an upper end of an uppermost communicating hole among the at least one communicating hole.

[0123] (5) The driving device according to (3), wherein the opening end is located below a lower end of an uppermost communicating hole among the at least one communicating hole.

[0124] (6) A drive device according to any one of (3) to (5), wherein the housing has a first component and a second component, the first component and the second component are axially connected to form the gear chamber, the inlet is arranged in the first component, the dividing wall is composed of a first part which is a part of the first component and a second part which are axially connected to each other, the connecting hole is arranged on the boundary between the first part and the second part, and the area of ​​the flow path cross-section of the connecting hole on the side closer to the second part than the boundary is larger than the area on the side closer to the first part than the boundary.

[0125] (7) A driving device according to any one of (3) to (6), wherein the partition wall extends in an arc shape along the tooth top of the gear ring, and a first connecting hole located at the lower end of the partition wall and a second connecting hole located above the first connecting hole are provided on the partition wall as the connecting holes.

[0126] (8) The driving device according to (7), wherein a cross-sectional area of ​​the second communicating hole is larger than a cross-sectional area of ​​the first communicating hole.

[0127] (9) A drive device according to any one of (1) to (8), wherein the plurality of gears comprises: the ring gear; and a plurality of transmission gears which transmit power to the ring gear, the housing comprises a side wall portion which covers the transmission mechanism from one axial side, the side wall portion comprising: a first side wall region which overlaps with the transmission gear when viewed from the axial direction; and a second side wall region which is located outside the first side wall region and overlaps with the ring gear when viewed from the axial direction, the second side wall region being located closer to the other axial side than the first side wall region.

[0128] (10) The drive device according to any one of (1) to (9), wherein at least one rib is provided on the inner side surface of the gear chamber, and the opening end is located on the side surface of the rib.

[0129] Description of symbols

[0130] 1: driving device; 2: motor; 3: transmission mechanism; 6: housing; 6A: motor chamber; 6B: gear chamber; 8: pump; 21: motor shaft; 41: first gear (transmission gear); 42: second gear (transmission gear); 43: third gear (transmission gear); 51: ring gear; 61: housing body (first component); 62: gear cover (second component); 62r: rib; 62s: side; 62w: side wall; 62A: first side wall area; 62B: second side wall area; 67: partition wall; 67a : The first connecting hole; 67b: the second connecting hole; 67P: the first part; 67Q: the second part; 90: flow path; 91p: the first inlet (inlet); 96: the lubrication supply flow path portion (the first flow path portion); 99: the terminal flow path portion (the second flow path portion); 99a: the opening end; 167a, 167b: connecting holes; A1: the first area; A2: the second area; B1, B2, B3, B4, B5, B6, B7: bearings; BL: boundary; J1: the first axis (motor axis); O: fluid.

Claims

1. A driving device, comprising: A motor having a motor shaft rotatable about a motor axis; A transmission mechanism, which is located on one axial side of the motor and has a plurality of gears for transmitting power of the motor; a plurality of bearings, the plurality of bearings supporting the transmission mechanism; a housing, which is provided with a motor chamber for accommodating the motor and a gear chamber for accommodating the transmission mechanism; a flow path for fluid flow, at least a portion of which is disposed in the housing; as well as a pump disposed in the flow path, sucking the fluid from an inlet opening in the gear chamber and delivering the fluid under pressure, The gear chamber is provided with a partition wall for partitioning the gear chamber into a first area and a second area. A ring gear having the largest diameter among the plurality of gears is arranged in the first region. The inlet is arranged in the second region, The housing has a cylindrical portion for holding the bearing. The flow path has: a first flow path portion that supplies the fluid to an inner peripheral surface of the cylindrical portion; and A second flow path portion extends from the inner peripheral surface of the cylindrical portion to an opening end located in the first region.

2. The driving device according to claim 1, wherein: The cylindrical portion is arranged in the second region or on the upper side of the second region.

3. The driving device according to claim 1, wherein: The partition wall is provided with at least one communication hole connecting the first region and the second region.

4. The driving device according to claim 3, wherein: The opening end is located below an upper end of a communicating hole disposed at an uppermost side among the at least one communicating hole.

5. The driving device according to claim 3, wherein: The opening end is located below a lower end of a communicating hole disposed at the uppermost side among the at least one communicating hole.

6. The driving device according to claim 3, wherein: The housing includes a first component and a second component, and the first component and the second component are butted against each other in the axial direction to form the gear chamber. The inlet is provided in the first component, The partition wall is formed by a first portion, which is a part of the first component, and a second portion, which is a part of the second component, being butted together in the axial direction. The connecting hole is provided at the boundary between the first part and the second part, An area of ​​the flow path cross section of the communicating hole on the second portion side relative to the boundary is larger than an area on the first portion side relative to the boundary.

7. The driving device according to any one of claims 3 to 6, wherein: The dividing wall extends in an arc shape along the tooth top of the gear ring. The partition wall is provided with a first communicating hole located at a lower end of the partition wall and a second communicating hole located above the first communicating hole as the communicating holes.

8. The driving device according to claim 7, wherein: A cross-sectional area of ​​the second communicating hole is larger than a cross-sectional area of ​​the first communicating hole.

9. The driving device according to claim 1, wherein: The plurality of gears have: the ring gear; as well as a plurality of transmission gears, the plurality of transmission gears transmitting power to the ring gear, The housing has a side wall portion covering the transmission mechanism from one axial side. The side wall portion has: a first side wall region, the first side wall region overlapping the transmission gear when viewed in the axial direction; and a second side wall region, when viewed from the axial direction, the second side wall region is located outside the first side wall region and overlaps with the gear ring, The second side wall region is located on the other side in the axial direction relative to the first side wall region.

10. The driving device according to claim 1, wherein: At least one rib is provided on the inner side of the gear chamber, The open end is located on a side of the rib.

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