Drive unit

Abstract

To provide a drive device that can be miniaturized overall. [Solution] The drive unit comprises a motor, a transmission mechanism, an inverter, a housing that houses these, a fluid passage, a refrigerant passage, a pump that pressurizes the fluid in the passage, and a cooler that exchanges heat between the fluid and the refrigerant. The housing has a motor housing for housing the motor, a transmission mechanism housing located on one axial side of the motor housing for housing the transmission mechanism, an inverter housing for housing the inverter, and a support portion located radially outward of the motor housing and below the inverter housing in the vertical direction when viewed from the axial direction, and connected to at least one of the outer circumference of the motor housing or the bottom of the inverter housing. The support portion supports at least one of the pump or the cooler, and the transmission mechanism has an output shaft centered on an output shaft parallel to the motor axis. At least a portion of the support portion overlaps the output shaft in the vertical direction.

Description

Technical Field

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

Background Art

[0002] Conventionally, a drive device is mounted on an electric vehicle or the like. Such a drive device is equipped with a cooling structure for cooling a rotating electric machine. Patent Document 1 discloses a structure in which a refrigerant is cooled by a cooling device (cooler) provided outside a motor (rotating electric machine), and the refrigerant is supplied to the motor by a pump provided outside the motor.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the drive device as described above, an inverter, a speed reduction device, etc. are attached. Such a drive device has a complex outer shape, and thus there is a problem that a dead space is likely to occur when mounted on a vehicle.

[0005] One aspect of the present invention aims to provide a drive device capable of achieving overall miniaturization in view of the above problems.

Means for Solving the Problems

[0006] One aspect of the drive device of the present invention comprises a motor having a rotor that rotates around a motor shaft and a stator surrounding the rotor; a transmission mechanism having a plurality of gears that transmits power from the motor; an inverter that controls the current supplied to the motor; a housing that houses the motor, the transmission mechanism, and the inverter; a fluid housed within the housing; a passage through which the fluid flows; at least a refrigerant for cooling the inverter; a refrigerant passage through which the refrigerant flows; a pump for pressurizing the fluid in the passage; and a cooler for heat exchange between the fluid and the refrigerant. The housing has a motor housing section for housing the motor; a transmission mechanism housing section located on one axial side of the motor housing section and housing the transmission mechanism; an inverter housing section for housing the inverter; and a support section located radially outward of the motor housing section and below the inverter housing section in the vertical direction when viewed from the axial direction, and connected to at least one of the outer periphery of the motor housing section or the bottom of the inverter housing section. The support portion supports at least one of the pump or the cooler, and the transmission mechanism has an output shaft centered on an output shaft parallel to the motor shaft. At least a portion of the support portion overlaps the output shaft in the vertical direction. [Effects of the Invention]

[0007] According to one aspect of the present invention, the drive device can be made smaller overall. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a conceptual diagram showing a drive device according to one embodiment. [Figure 2] Figure 2 is a perspective view showing a drive device according to one embodiment. [Figure 3] Figure 3 is a front view of a drive device according to one embodiment. [Figure 4] Figure 4 is a side view of a drive device according to one embodiment. [Figure 5] Figure 5 is a perspective view showing a part of the drive unit of one embodiment. [Modes for carrying out the invention]

[0009] The following description of a drive device according to an embodiment of the present invention will be made with reference to the drawings. However, the scope of the present invention is not limited to the following embodiments, and can be modified as appropriate within the scope of the technical concept of the present invention.

[0010] In the following explanation, the direction of gravity is defined and explained based on the positional relationship when the drive unit 1 is mounted on a vehicle located on a horizontal road surface. 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 represents the vertical direction. In the following explanation, the +Z direction side will be referred to as the "upper side" and the -Z direction side as the "lower side". The X axis direction is perpendicular to the Z axis direction and represents the front-to-rear direction of the vehicle on which the drive unit 1 is mounted. In the following explanation, the +X direction side will be referred to as the "rear side of the vehicle" and the -X direction side as the "front side of the vehicle". The Y axis direction is perpendicular to both the X axis direction and the Z axis direction and represents the width direction of the vehicle.

[0011] In the following explanation, unless otherwise specified, the direction parallel to the motor shaft J1 of motor 2 (the Y-axis direction) will simply be referred to as the "axial direction." The side of the axial direction in which the Y-axis arrow points (+Y side) will be referred to as the "one axial side." The side of the axial direction opposite to the side in which the Y-axis arrow points (-Y side) will be referred to as the "other axial side." The radial direction centered on the motor shaft J1 will simply be referred to as the "radial direction," and the circumferential direction centered on the motor shaft J1, that is, the direction around the axis of the motor shaft J1, will simply be referred to as the "circumferential direction." The circumferential direction is indicated by the arrow θ in each figure. The side of the circumferential direction in which the arrow θ points will be referred to as the "one circumferential side." The side of the circumferential direction opposite to the side in which the arrow θ points will be referred to as the "other circumferential side." The one circumferential side is the side that proceeds clockwise around the motor shaft J1 when viewed from the one axial side. The other circumferential side is the side that proceeds counterclockwise around the motor shaft J1 when viewed from the one axial side. However, the above-mentioned "parallel direction" also includes a nearly parallel direction. Furthermore, the terms "upper side," "lower side," "front side of the vehicle," and "rear side of the vehicle" are merely names used to describe the relative positions of the parts, and the actual relative positions may differ from those indicated by these names.

[0012] The following describes a drive device 1 according to an exemplary embodiment of the present invention, based on the drawings. Figure 1 is a conceptual diagram of a drive device 1 according to one embodiment. Figure 1 is merely a conceptual diagram, and the arrangement and dimensions of each part may not be the same as in reality.

[0013] The drive unit 1 is installed in vehicles that use a motor as a power source, such as hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHVs), and electric vehicles (EVs), and is used as the power source for those vehicles.

[0014] As shown in Figure 1, the drive unit 1 comprises a motor 2, a transmission mechanism 3, a housing 6, an inverter 7, a pump 8, a cooler 9, an oil O which is a fluid contained within the housing 6, and a refrigerant L.

[0015] <motor> As shown in Figure 1, the motor 2 is housed inside the motor housing 81 of the housing 6. The motor 2 comprises a rotor 20 and a stator 30 located radially outside the rotor 20. The motor 2 is an inner rotor type motor, with the rotor 20 rotatably arranged inside the stator 30 around the motor shaft J1.

[0016] The rotor 20 rotates when current is supplied to the stator 30 from a battery (not shown) via an inverter or the like. The rotor 20 has a shaft 21, a rotor core 24, and a rotor magnet (not shown). The rotor 20 rotates around the motor shaft J1. The torque of the rotor 20 is transmitted to the transmission mechanism 3.

[0017] The shaft 21 is substantially cylindrical in shape, extending axially around the motor shaft J1, which is oriented horizontally and in the width direction of the vehicle. The shaft 21 rotates around the motor shaft J1. The shaft 21 is a hollow shaft with a hollow section inside. The shaft 21 extends in the direction of the motor shaft J1, straddling the inside of the motor housing 81 and the inside of the transmission mechanism housing 82. The shaft 21 is composed of a first shaft 21A and a second shaft 21B, which are arranged coaxially and connected to each other.

[0018] The first shaft 21A and the second shaft 21B are hollow and substantially cylindrical, extending in the axial direction. The first shaft 21A is disposed inside the motor housing portion 81. The second shaft 21B is disposed inside the transmission mechanism housing portion 82. The first shaft 21A and the second shaft 21B are connected to each other inside a partition wall 61c, which will be described later. The first shaft 21A and the second shaft 21B rotate synchronously about the motor shaft J1. In the present embodiment, the inner diameter of one end portion of the first shaft 21A in the axial direction is larger than the outer diameter of the other end portion of the second shaft 21B in the axial direction. Splines that mesh with each other are provided on the inner peripheral surface of one end portion of the first shaft 21A in the axial direction and the outer peripheral surface of the other end portion of the second shaft 21B in the axial direction. By fitting the one end portion of the first shaft 21A in the axial direction and the other end portion of the second shaft 21B in the axial direction together, the first shaft 21A and the second shaft 21B are connected to each other. Note that a configuration may be adopted in which the end portion of the first shaft 21A is inserted into the hollow portion of the end portion of the second shaft 21B for connection. In this case, splines that mesh with each other are provided on the outer peripheral surface of the end portion of the first shaft 21A and the inner peripheral surface of the end portion of the second shaft 21B.

[0019] The rotor core 24 is formed by laminating a plurality of silicon steel sheets. The rotor core 24 is substantially columnar, extending in the axial direction. A plurality of rotor magnets (not shown) are fixed to the rotor core 24. In the rotor 20, the magnetic poles formed by the plurality of rotor magnets are arranged alternately along the circumferential direction.

[0020] The stator 30 surrounds the rotor 20 from the radially outer side. The stator 30 includes a stator core 32, a coil 31, and an insulator (not shown) interposed between the stator core 32 and the coil 31. The stator 30 is held by the housing 6.

[0021] The stator core 32 has a plurality of magnetic pole teeth (not shown) extending radially inward from the inner peripheral surface of the annular yoke. Coil wires are disposed between the magnetic pole teeth. The coil wires disposed between the magnetic pole teeth constitute the coil 31. The coil wires are connected to the inverter 7 via a bus bar (not shown). The coil 31 has a coil end 31a protruding from the axial end surface of the stator core 32. The coil end 31a protrudes axially on both sides of the rotor core 24 of the rotor 20.

[0022] <Transmission mechanism> As shown in FIG. 1, the transmission mechanism 3 transmits the power of the motor 2 to the output shaft 55. The transmission mechanism 3 is housed inside the transmission mechanism housing portion 82 of the housing 6. The transmission mechanism 3 is connected to the shaft 21 inside the transmission mechanism housing portion 82. The transmission mechanism 3 is connected to the output shaft 55 inside the transmission mechanism housing portion 82. The transmission mechanism 3 has a speed reduction device 4 and a differential device 5. The transmission mechanism 3 has a plurality of gears. The torque output from the motor 2 is transmitted to the differential device 5 via the plurality of gears of the speed reduction device 4.

[0023] <Speed reduction device> As shown in FIG. 1, the speed reduction device 4 is connected to the shaft 21. More specifically, the speed reduction device 4 is connected to the second shaft 21B. The speed reduction device 4 has a function of reducing the rotational speed of the motor 2 and increasing the torque output from the motor 2 according to the reduction ratio. The speed reduction device 4 transmits the torque output from the motor 2 to the differential device 5. The speed reduction device 4 has a first gear 41, a second gear 42, a third gear 43, and an intermediate shaft 45. The torque output from the motor 2 is transmitted to the ring gear 51 of the differential device 5 via the shaft 21, the first gear 41, the second gear 42, the intermediate shaft 45, and the third gear 43. The gear ratio of each gear, the number of gears, etc. can be variously changed according to the required reduction ratio. In the present embodiment, the speed reduction device 4 is a parallel shaft gear type reduction gear in which the axial centers of each gear are arranged parallel to the motor shaft J1. Note that the speed reduction device 4 may be another type of reduction gear.

[0024] The first gear 41 is provided on the outer circumferential surface of the shaft 21. The first gear 41 rotates together with the shaft 21 around the motor shaft J1. The intermediate shaft 45 extends along the intermediate shaft J2, which is parallel to the motor shaft J1. The intermediate shaft 45 rotates around the intermediate shaft J2. The intermediate shaft 45 is a hollow cylindrical shape that extends in the axial direction. The second gear 42 and the third gear 43 are provided on the outer circumferential surface of the intermediate shaft 45. The second gear 42 and the third gear 43 are connected via the intermediate shaft 45. The second gear 42 and the third gear 43 rotate around the intermediate shaft J2. The second gear 42 meshes with the first gear 41. The third gear 43 meshes with the ring gear 51 of the differential 5. The third gear 43 is located on the bulkhead 61c side relative to the second gear 42.

[0025] <Differential device> As shown in Figure 1, the differential gear 5 is connected to the motor 2 via the reduction gear 4. The differential gear 5 is a device for transmitting the torque output from the motor 2 to the wheels of the vehicle. The differential gear 5 has the function of transmitting the same torque to the axles of both the left and right wheels while absorbing the speed difference between the left and right wheels when the vehicle turns. The differential gear 5 includes a ring gear 51, a differential case 50, and a differential mechanism 50c located inside the differential case 50.

[0026] The ring gear 51 rotates around the output shaft J3, which is parallel to the motor shaft J1. Torque output from the motor 2 is transmitted to the ring gear 51 via the reduction gear 4. The ring gear 51 meshes with the third gear 43. The ring gear 51 is fixed to the outer surface of the differential case 50.

[0027] The differential case 50 has a case portion 50b that houses the differential mechanism 50c inside, and shaft portions 50a that protrude from the case portion 50b in the axial direction, on one side and the other side, respectively. The shaft portion 50a is cylindrical and extends axially around the output shaft J3. The shaft portion 50a rotates together with the ring gear 51 around the output shaft J3.

[0028] A pair of output shafts 55 are connected to the differential 5. The pair of output shafts 55 protrude axially from the differential case 50 of the differential 5, on one side and the other side. The pair of output shafts 55 are positioned inside the shaft portion 50a. The pair of output shafts 55 are rotatably supported on the inner circumferential surface of the shaft portion 50a via bearings (not shown). The output shafts 55 rotate about the output shaft J3. In other words, the transmission mechanism 3 has output shafts 55 centered on the output shaft J3 which is parallel to the motor shaft J1.

[0029] The torque output from motor 2 is transmitted to the ring gear 51 of differential gear 5 via shaft 21, first gear 41, second gear 42, intermediate shaft 45, and third gear 43, and is further output to output shaft 55 via differential gear 5.

[0030] <Housing> As shown in Figure 1, the motor 2, the transmission mechanism 3, and the inverter 7 are housed in the internal space of the housing 6. The housing 6 comprises a motor housing section 81, a transmission mechanism housing section 82, an inverter housing section 84, a support section 83, and a pump holding section 85. The motor 2 is housed inside the motor housing section 81. The transmission mechanism 3 is housed inside the transmission mechanism housing section 82. The inverter 7 is housed inside the inverter housing section 84. The support section 83 supports the pump 8 and the cooler 9. The pump holding section 85 constitutes a part of the pump 8. The pump holding section 85 houses the mechanical parts of the pump 8. In this embodiment, the support section 83 supports the pump 8 by being connected to the pump holding section 85.

[0031] As shown in Figure 2, the housing 6 includes a housing body 61, a gear cover 62, a motor cover 63, an inverter cover 64, and an upper cover member 65. The gear cover 62 is located on one axial side of the housing body 61. The motor cover 63 is located on the other axial side of the housing body 61. The inverter cover 64 is located on the upper side of the housing body 61. The upper cover member 65 is located on the upper side of the inverter cover 64.

[0032] As shown in Figure 1, the motor housing section 81 is composed of a housing body 61 and a motor cover 63. The transmission mechanism housing section 82 is composed of a housing body 61 and a gear cover 62. The inverter housing section 84 is composed of an inverter cover 64 and an upper cover member 65. Thus, the housing 6 has a motor housing section 81, a transmission mechanism housing section 82, and an inverter housing section 84.

[0033] As shown in Figures 1 and 2, the housing body 61 has a cylindrical peripheral wall portion 61a, a side plate portion 61b located on one axial side of the peripheral wall portion 61a, a support portion 83, a pump holding portion 85, and an output shaft support portion 61j. The motor 2 is housed inside the peripheral wall portion 61a. In this embodiment, the peripheral wall portion 61a is part of the motor housing portion 81.

[0034] As shown in Figure 1, the side plate portion 61b has a partition wall 61c. The partition wall 61c covers the opening on one axial side of the peripheral wall portion 61a. In this embodiment, the partition wall 61c is part of the motor housing portion 81.

[0035] As shown in Figures 1 and 2, the support portion 83 supports the pump 8 and the cooler 9. The support portion 83 protrudes radially outward from the peripheral wall portion 61a. The support portion 83 is located on the other axial side relative to the side plate portion 61b. The support portion 83 is located below the inverter cover 64, which will be described later. The support portion 83 is connected to the peripheral wall portion 61a, the side plate portion 61b, and the inverter cover 64. The support portion 83 has a cooler support portion 61g. The output shaft 55 passes through the support portion 83 in the axial direction.

[0036] As shown in Figures 2 and 3, the cooler support portion 61g is provided on the outer circumferential surface of the support portion 83 that faces the rear side of the vehicle (+X direction). In this embodiment, the cooler support portion 61g is provided with four openings (not shown). The four openings are connected to the inlet 9a, outlet 9b, refrigerant inlet 9c, and refrigerant outlet 9d of the cooler 9, which will be described later.

[0037] As shown in Figure 1, the pump holder 85 is located below the support portion 83 and is connected to the lower end of the support portion 83. That is, the support portion 83 supports the pump 8 from above. The pump holder 85 is located radially outward from the peripheral wall portion 61a. That is, the pump 8 is located radially outward from the peripheral wall portion 61a. The pump holder 85 is provided with a pump mechanism housing hole 61i. The pump mechanism housing hole 61i is a hole that houses the mechanism portion of the pump 8. The pump mechanism housing hole 61i is a hole that extends in the axial direction.

[0038] As shown in Figure 2, the output shaft support portion 61j protrudes radially outward from the other axial end of the peripheral wall portion 61a. The output shaft support portion 61j supports the output shaft 55 via a bearing (not shown). The output shaft support portion 61j is provided with an output shaft through hole 61k that opens in the axial direction. The output shaft 55 passes through the output shaft through hole 61k in the axial direction.

[0039] As shown in Figure 2, the motor cover 63 is fixed to the peripheral wall portion 61a of the housing body 61. The motor cover 63 closes the opening on the other axial side of the housing body 61. In this embodiment, the motor cover 63 is part of the motor housing portion 81.

[0040] As shown in Figure 4, the gear cover 62 is fixed to one axial side of the housing body 61. As shown in Figure 1, the gear cover 62 has a concave shape that opens toward the housing body 61 side (i.e., the other axial side). The opening of the gear cover 62 is covered by the side plate portion 61b. The transmission mechanism 3 is housed in the space between the gear cover 62 and the side plate portion 61b. In this embodiment, the gear cover 62 is part of the transmission mechanism housing portion 82.

[0041] As shown in Figures 2 and 3, the inverter cover 64 is fixed to the upper side of the housing body 61. The inverter cover 64 is positioned across the upper side of the peripheral wall portion 61a and the upper side of the support portion 83. The inverter cover 64 houses the inverter 7 inside. The inverter cover 64 has a bottom plate portion 64a and a box-shaped portion 64b.

[0042] The bottom plate portion 64a is the lower part of the inverter cover 64. The bottom plate portion 64a is fixed to the upper side of the housing body 61. When viewed from above, the bottom plate portion 64a is a roughly rectangular plate. The bottom plate portion 64a is located downwards as you move from the front side of the vehicle (-X direction) to the rear side of the vehicle (+X direction). The front end of the bottom plate portion 64a (-X direction) is located further to the rear (+X direction) of the vehicle than the front end of the housing body 61 (-X direction). The rear end of the bottom plate portion 64a (+X direction) is located further to the rear (+X direction) of the vehicle than the rear end of the support portion 83 (+X direction). A box-shaped portion 64b is connected to the upper side of the bottom plate portion 64a. In this embodiment, the bottom plate portion 64a is part of the inverter housing portion 84.

[0043] The box-shaped section 64b extends upward from the bottom plate section 64a. Viewed from above, the outer shape of the box-shaped section 64b is approximately rectangular. The box-shaped section 64b houses the inverter 7 inside. As shown in Figure 3, the outer shape of the box-shaped section 64b is approximately trapezoidal when viewed in the axial direction. The bottom 64c of the box-shaped section 64b is located lower as you move from the front side of the vehicle (-X direction) to the rear side of the vehicle (+X direction). The upper end of the box-shaped section 64b extends approximately in the longitudinal direction of the vehicle (X-axis direction) from the front side of the vehicle (-X direction) to the rear side of the vehicle (+X direction). Therefore, the vertical dimension of the box-shaped section 64b is larger as you move from the front side of the vehicle (-X direction) to the rear side of the vehicle (+X direction). In other words, the vertical dimension of the rear end (+X direction side) of the box-shaped portion 64b is greater than the vertical dimension of the front end (-X direction side) of the vehicle. Inside the box-shaped portion 64b, a first region 64d and a second region 64e are provided.

[0044] The first region 64d is the part of the box-shaped portion 64b that is on the vehicle front side (-X direction side). The first region 64d is located above the peripheral wall portion 61a. When viewed from the vertical direction, the first region 64d overlaps with the peripheral wall portion 61a. In other words, the first region 64d is located above the motor housing portion 81. That is, the first region 64d is located radially outside the motor housing portion 81. The second region 64e is the part of the box-shaped portion 64b that is on the vehicle rear side (+X direction side). The second region 64e is located above the support portion 83. That is, in the circumferential direction, the second region 64e is located between the first region 64d and the other circumferential side of the support portion 83. When viewed from the vertical direction, the second region 64e does not overlap with the peripheral wall portion 61a and is located at a different position from the peripheral wall portion 61a when viewed from the vertical direction. The vertical dimension of the second region 64e is greater than the vertical dimension of the first region 64d. In other words, the circumferential dimension of the second region 64e is greater than the circumferential dimension of the first region 64d.

[0045] The top cover member 65 is fixed to the upper side of the inverter cover 64. The top cover member 65 closes the upper opening of the box-shaped portion 64b. The top cover member 65 is a roughly rectangular plate. In this embodiment, the top cover member 65 is part of the inverter housing portion 84.

[0046] An oil reservoir P, where oil O (described later) accumulates, is provided in the lower region inside the transmission mechanism housing 82. In this embodiment, the bottom 81a of the motor housing 81 is located above the bottom 82a of the transmission mechanism housing 82. A partition hole (not shown) is also provided in the partition wall 61c. The partition hole connects the inside of the motor housing 81 and the inside of the transmission mechanism housing 82. The oil O accumulated in the lower region inside the motor housing 81 moves to the oil reservoir P inside the transmission mechanism housing 82 via the partition hole.

[0047] As shown in Figures 1 and 2, the transmission mechanism housing 82 is located on one axial side of the motor housing 81. The inverter housing 84 is located above the motor housing 81. That is, the inverter housing 84 is located radially outward of the motor housing 81. Furthermore, the transmission mechanism housing 82 protrudes further to the rear of the vehicle (+X direction) than the motor housing 81. In other words, the transmission mechanism housing 82 protrudes radially outward from the motor housing 81. The inverter housing 84 protrudes further to the rear of the vehicle (+X direction) than the motor housing 81. In other words, the inverter housing 84 protrudes radially outward from the motor housing 81. Therefore, a space is formed on the rear of the vehicle (+X direction) of the motor housing 81, on the other axial side of the transmission mechanism housing 82, and below the inverter housing 84. Hereafter, this space will be referred to as dead space.

[0048] In this embodiment, the support portion 83 is located radially outward of the motor housing portion 81 and below the inverter housing portion 84, as described above. Furthermore, the support portion 83 is located on the other axial side of the transmission mechanism housing portion 82. In other words, the support portion 83 is positioned in a dead space.

[0049] Furthermore, as described above, the support portion 83 is connected to the peripheral wall portion 61a. That is, the support portion 83 is connected to the outer periphery of the motor housing portion 81. As described above, the support portion 83 is connected to the lower end of the inverter cover 64. That is, the support portion 83 is connected to the bottom of the inverter housing portion 84. As described above, the support portion 83 is connected to the side plate portion 61b. That is, the support portion 83 is connected to the transmission mechanism housing portion 82. In other words, the support portion 83 is connected to the motor housing portion 81, the transmission mechanism housing portion 82, and the inverter housing portion 84.

[0050] <oil> As shown in Figure 1, when the drive unit 1 is driven, the oil O circulates within the oil passage 90 provided in the housing 6. The oil passage 90 is the path through which the oil O flows from the oil reservoir P to the motor 2 and the transmission mechanism 3. The oil O is used to cool the motor 2. The oil O is also used to lubricate the reduction gear 4 and the differential gear 5. The oil O may also be used to lubricate at least one bearing located inside the drive unit 1. Since the oil O functions as both a lubricant and a coolant, it is preferable to use an oil equivalent to a low-viscosity automatic transmission fluid (ATF). In this embodiment, the fluid is oil O.

[0051] <Oil road> As shown in Figure 1, the oil passage 90 is a passage through which oil O flows. In other words, the drive unit 1 is equipped with a passage through which fluid (oil O) flows. The oil passage 90 spans the motor housing 81, the transmission mechanism housing 82, and the support section 83. The oil passage 90 is a path for oil O that guides oil O from the oil reservoir P, through the motor 2 and the transmission mechanism 3, and back to the oil reservoir P.

[0052] In this specification, "oil passage" refers to the path of oil O circulating inside the drive unit 1. Therefore, "oil passage" is a concept that includes not only "flow paths" that form a steady flow of oil O in a steady direction, but also paths where oil O is temporarily retained (e.g., oil reservoirs P) and paths through which oil O drips.

[0053] As shown in Figure 1, in the oil passage 90, oil O flows from the oil reservoir P through the motor housing 81 and the transmission mechanism housing 82, and is supplied to the motor 2 and the transmission mechanism 3, respectively. The oil O supplied to the motor 2 cools the motor 2 by absorbing heat from the rotor 20 and stator 30 as it travels along the outer surface of the stator 30 and the rotor 20. The oil O that travels along the outer surface of the stator 30 and the rotor 20 drips downward and accumulates in the lower region of the motor housing 81. The oil O that has accumulated in the lower region of the motor housing 81 returns to the oil reservoir P through the partition holes (not shown). The oil O supplied to the transmission mechanism 3 via the ring gear 51 (described later) and the various flow paths (described later) is supplied to the tooth surfaces of each gear in the transmission mechanism 3, lubricating the tooth surfaces of each gear. The oil O that travels along the tooth surfaces of each gear drips downward and returns to the oil reservoir P. The oil volume of the oil reservoir P is such that, for example, when the drive unit 1 is stopped, a portion of the bearing of the differential unit 5 is submerged in the oil O.

[0054] The oil passage 90 includes a first passage 91a, a second passage 91b, a cooler internal passage 91c, a connecting passage 92a, a relay piping internal passage 92b, a motor housing internal passage 93, a third passage 94, a fourth passage 95, a fifth passage 96A, a sixth passage 96B, a seventh passage 97, a first shaft internal passage 98A, a second shaft internal passage 98B, and an intermediate shaft internal passage 99. A pump 8 and a cooler 9 are provided along the path of the oil passage 90. The pump 8 pumps the oil O. The cooler 9 cools the oil O flowing through the cooler internal passage 91c.

[0055] In this embodiment, the first channel 91a, the second channel 91b, the connecting channel 92a, the motor housing channel 93, the fourth channel 95, and the seventh channel 97 are provided inside the wall of the housing 6. The first shaft channel 98A and the second shaft channel 98B are provided inside the shaft 21, and the intermediate shaft channel 99 is provided inside the intermediate shaft 45. Therefore, there is no need to prepare separate pipe materials to provide these channels, which contributes to reducing the number of parts.

[0056] The first flow path 91a connects the oil reservoir P to the pump 8. In this embodiment, the first flow path 91a is located inside the wall of the housing 6. More specifically, the first flow path 91a is a flow path that extends at least axially toward the other side inside the support portion 83. In this embodiment, the first flow path 91a is a straight flow path.

[0057] In this embodiment, the pump 8 is an electrically driven electric pump. The pump 8 draws oil O from the oil reservoir P via the first passage 91a, pumps the oil O, and supplies the oil O to the motor 2 and transmission mechanism 3 via the second passage 91b, cooler 9, connecting passage 92a, etc. In other words, the drive device 1 includes a pump 8 that pumps the oil O in the oil passage 90. As shown in Figures 3 and 4, in this embodiment, the pump 8 is located below the support portion 83. That is, the pump 8 is located on one side in the circumferential direction relative to the support portion 83 when viewed from the axial direction. The lower end position of the pump 8 is located above the lower end positions of the motor housing portion 81 and the transmission mechanism housing portion 82. That is, the position of one end of the pump 8 in the circumferential direction is located on the other side in the circumferential direction relative to the position of one end of the motor housing portion 81 and the transmission mechanism housing portion 82 in the circumferential direction. The other end of the pump 8 in the axial direction is located on one side in the axial direction relative to the other end of the motor housing portion 81 in the axial direction. Viewed from below (-Z direction), the pump 8 overlaps with the inverter housing 84. In other words, when viewed from above, the pump 8 is hidden beneath the inverter housing 84. Furthermore, a virtual arc C1 centered on the motor shaft J1 and passing through the radially outer end of the pump 8 overlaps with the inverter housing 84. In other words, the pump 8 overlaps with the inverter housing 84 in the circumferential direction. Therefore, in this embodiment, the pump 8 is positioned in dead space.

[0058] The pump 8 is housed in a pump mechanism housing hole 61i that extends axially in the housing 6. The pump 8 is supported by the support portion 83, by which the pump holding portion 85 is connected. As shown in Figure 5, the pump 8 has a pump mechanism portion 8a, a pump motor 8b, an inlet 8c, an outlet 8d, and a pump holding portion 85 (see Figure 2, omitted in Figure 5) that houses these. The inlet 8c of the pump 8 is located on one side in the axial direction. The pump motor 8b is located on the other side in the axial direction.

[0059] The pump mechanism 8a is located on one axial side of the pump motor 8b. The inlet 8c is located at the axial end of the pump mechanism 8a. The discharge port 8d is located above the pump mechanism 8a. In this embodiment, the pump 8 is a trochoidal pump in which an external gear (not shown) and an internal gear mesh and rotate. The internal gear of the pump mechanism 8a is rotated by the pump motor 8b. The gap between the internal gear and the external gear of the pump mechanism 8a is connected to the inlet 8c and the discharge port 8d. The inlet 8c is connected to the first flow path 91a, and the discharge port 8d is connected to the second flow path 91b. The pump 8 draws up oil O from the oil reservoir P via the first flow path 91a and supplies the oil O to the second flow path 91b.

[0060] The pump motor 8b rotates around the rotation axis J4. The rotation axis J4 is parallel to the motor axis J1. The rotation axis J4 is located below the rotation axes J1, J2, and J3 of the respective shafts of the motor 2 and the transmission mechanism 3. The dimensions of the pump 8 having the pump motor 8b tend to be longer in the direction of the rotation axis J4 compared to the radial direction of the rotation axis J4. Therefore, for example, if the pump 8 is positioned with the rotation axis J4 perpendicular to the motor axis J1, the pump 8 will protrude radially from the dead space, and the drive unit 1 may become larger in the radial direction. However, according to this embodiment, the pump 8 is positioned with the rotation axis J4 parallel to the motor axis J1. Therefore, the entire pump 8 can be placed in the dead space. This suppresses an increase in the radial and axial projected area of ​​the drive unit 1, and makes the overall drive unit 1 smaller.

[0061] As shown in Figure 1, the second flow path 91b connects the pump 8 and the cooler 9. More specifically, the second flow path 91b connects the discharge port 8d of the pump 8 and the inlet 9a of the cooler 9. In this embodiment, the second flow path 91b is provided inside the housing 6. More specifically, the second flow path 91b is a flow path that extends approximately in the X-axis direction inside the support portion 83. In this embodiment, the second flow path 91b is linear.

[0062] As shown in Figure 3, the cooler 9 is fixed to the cooler support portion 61g of the support portion 83. The cooler 9 is supported by the support portion 83. The cooler 9 is positioned on the rear side of the vehicle (+X direction side) relative to the support portion 83. In other words, the cooler 9 is positioned radially outward relative to the support portion 83. Also, the cooler 9 is positioned radially outward relative to the output shaft 55. As shown in Figures 3 and 4, the lower end of the cooler 9 is located above the lower end of the motor housing portion 81 and the transmission mechanism housing portion 82. That is, the position of one circumferential end of the cooler 9 is located on the other circumferential side of the position of one circumferential end of the motor housing portion 81 and the transmission mechanism housing portion 82. The other axial end of the cooler 9 is located on one axial side of the other axial end of the motor housing portion 81. When viewed from below (-Z direction side), the cooler 9 overlaps with the inverter housing portion 84. In other words, the cooler 9 is hidden beneath the inverter housing 84 when viewed from above. Also, a virtual arc C2 centered on the motor shaft J1 and passing through the radially outer end of the cooler 9 coincides with the inverter housing 84. That is, the cooler 9 overlaps with the inverter housing 84 in the circumferential direction. Therefore, in this embodiment, the cooler 9 is positioned in dead space.

[0063] As shown in Figure 1, the cooler 9 is connected to the second channel 91b and the connecting channel 92a. A cooler internal passage 91c through which oil O flows is provided inside the cooler 9. As shown in Figure 4, the cooler internal passage 91c and the second passage 91b are connected via an inlet 9a of the cooler. The cooler internal passage 91c and the connecting passage 92a are connected via an outlet 9b of the cooler. The cooler internal passage 91c connects the inlet 9a and the outlet 9b inside the cooler 9. As shown in Figures 3 and 4, the inlet 9a is located below the output shaft J3. The outlet 9b is located above the output shaft J3. The cooler internal passage 91c is positioned to overlap the output shaft J3 in the radial direction of the motor shaft J1. As shown in Figure 3, viewed in the axial direction, the cooler internal passage 91c extends in the circumferential direction of the output shaft J3.

[0064] As will be described later, a cooler internal refrigerant passage 74 is provided inside the cooler 9. Coolant L, cooled by the radiator (not shown), flows through the cooler internal refrigerant passage 74. Therefore, the oil O passing through the cooler internal passage 91c is cooled by heat exchange with the coolant L passing through the cooler internal refrigerant passage 74.

[0065] As described above, in this embodiment, the pump 8 and cooler 9 are placed in dead space. Therefore, as shown in Figure 3, when viewed from the axial direction, the pump 8 and cooler 9 overlap with the transmission mechanism housing 82. Since the transmission mechanism 3 is housed inside the transmission mechanism housing 82, the axial projected area of ​​the transmission mechanism housing 82 is determined by the size of each gear in the transmission mechanism 3. The size of each gear constituting the transmission mechanism 3 is set to satisfy the desired gear ratio. Therefore, it is difficult to reduce the axial projected area of ​​the transmission mechanism housing 82 without changing the size of each gear. However, according to this embodiment, the pump 8 and cooler 9 overlap with the transmission mechanism housing 82 in the axial direction. Therefore, compared to the axial projected area of ​​the drive unit 1 when the pump 8 and cooler 9 do not overlap with the transmission mechanism housing 82 in the axial direction, it is possible to suppress the increase in the axial projected area of ​​the drive unit 1 due to the cooler 9 and pump 8.

[0066] In this embodiment, the pump 8 and cooler 9 are positioned in dead space. Therefore, as shown in Figure 4, when viewed from the rear side of the vehicle (+X direction), the pump 8 and cooler 9 overlap the motor housing 81. In other words, when viewed radially, the pump 8 and cooler 9 overlap the motor housing 81. The motor 2 is housed inside the motor housing 81. The radial projected area of ​​the motor housing 81 is determined by, for example, the size of the rotor 20 and stator 30. The size of the rotor 20 and stator 30 is set to satisfy the desired output torque. Therefore, it is difficult to reduce the radial projected area of ​​the motor housing 81 without changing the desired output torque. However, according to this embodiment, the pump 8 and cooler 9 overlap the motor housing 81 radially. Compared to the radial projected area of ​​the drive unit 1 when the pump 8 and cooler 9 do not overlap the motor housing 81 radially, it is possible to suppress the increase in the radial projected area of ​​the drive unit 1 due to the pump 8 and cooler 9.

[0067] In this embodiment, the pump 8 and cooler 9 are placed in dead space. Therefore, as shown in Figure 3, when viewed from below (-Z direction), the pump 8 and cooler 9 overlap the inverter housing 84. In other words, the pump 8 and cooler 9 overlap the inverter housing 84 vertically. Also, as described above, the pump 8 and cooler 9 overlap the inverter housing 84 circumferentially. The inverter 7 is housed inside the inverter housing 84. The vertical and circumferential projected area of ​​the inverter housing 84 is determined by the size of the inverter 7. The size of the inverter 7 is determined, for example, by the number and size of electronic components. Therefore, it is difficult to reduce the vertical and circumferential projected area of ​​the inverter housing 84 without changing the electronic components, etc. However, in this embodiment, the pump 8 and cooler 9 overlap the inverter housing 84 vertically and circumferentially, respectively. Therefore, compared to the projected area of ​​the drive unit 1 in the vertical and circumferential directions when the pump 8 and cooler 9 do not overlap with the inverter housing 84 in the vertical and circumferential directions, respectively, it is possible to suppress the increase in the projected area of ​​the drive unit 1 in the vertical and circumferential directions due to the pump 8 and cooler 9.

[0068] As shown in Figure 1, the connecting passage 92a connects to the cooler 9 and the passage 92b inside the relay piping. More specifically, one end of the connecting passage 92a connects to the outlet 9b of the cooler 9. The other end of the connecting passage 92a connects to the passage 93 inside the motor housing, which will be described later, via the passage 92b inside the relay piping. In other words, the oil passage 90 has a connecting passage 92a that connects to the passage 93 inside the motor housing and the cooler 9. In this embodiment, the connecting passage 92a extends linearly inside the support portion 83 toward the front of the vehicle (-X direction).

[0069] The internal flow path 92b of the relay pipe connects to the connecting flow path 92a and the internal flow path 93 of the motor housing. The internal flow path 92b of the relay pipe is located inside the relay pipe 67. The relay pipe 67 is a hollow tubular shape that extends substantially in the axial direction. The relay pipe 67 connects to the inside of the support section 83 and the inside of the motor cover 63. Oil O is supplied from the support section 83 to the motor housing 81 via the internal flow path 92b of the relay pipe.

[0070] The motor housing internal flow path 93 is connected to the relay piping internal flow path 92b, the third flow path 94, and the first shaft internal flow path 98A. The motor housing internal flow path 93 is located inside the motor cover 63. In other words, the oil passage 90 has the motor housing internal flow path 93 provided in the motor housing 81. In this embodiment, the motor housing internal flow path 93 extends linearly from the connection point with the relay piping internal flow path 92b toward the connection point with the first shaft internal flow path 98A. The motor housing internal flow path 93 branches into the third flow path 94 along its path. As a result, oil O is supplied to the first shaft internal flow path 98A and the third flow path 94.

[0071] The third flow path 94 connects to the motor housing internal flow path 93 and the fourth flow path 95. The third flow path 94 is located inside the first supply pipe 68A. The first supply pipe 68A is a hollow tubular shape extending substantially in the axial direction. The first supply pipe 68A connects the inside of the motor cover 63 and the inside of the partition wall 61c. The first supply pipe 68A is located inside the motor housing 81, substantially above the motor 2. In the third flow path 94, the oil O flows axially along the substantially upper side of the motor 2.

[0072] The first supply pipe 68A is provided with an injection hole (not shown) that opens towards the motor 2. Therefore, in the third flow path 94, a portion of the oil O is injected into the motor 2 through the injection hole. That is, the third flow path 94 supplies oil O to the motor 2 from the radially outer side. As the oil O supplied to the motor 2 travels along the surfaces of the rotor 20 and stator 30, it absorbs heat from the rotor 20 and stator 30, cooling the entire motor 2. Furthermore, the oil O drips from the motor 2 and accumulates at the bottom 81a of the motor housing 81, returning to the oil reservoir P through the partition hole (not shown). A portion of the oil O supplied to the third flow path 94 reaches the fourth flow path 95.

[0073] Furthermore, the first supply pipe 68A is provided with an ejection hole that sprays oil O onto the bearings in the transmission mechanism housing 82 via an opening 61m provided in the partition wall 61c. In other words, in the third flow path 94, a portion of the oil O is supplied to the bearings through the ejection hole and the opening 61m.

[0074] The fourth passage 95 connects to the third passage 94, the fifth passage 96A, the sixth passage 96B, and the intermediate shaft passage 99. The fourth passage 95 extends inside the partition wall 61c. In other words, the oil passage 90 extends to the motor housing 81. In this embodiment, the fourth passage 95 extends linearly from the connection point with the third passage 94 toward the connection points with the fifth passage 96A and the sixth passage 96B. One end of the fourth passage 95 branches into the fifth passage 96A and the sixth passage 96B. The fourth passage 95 also branches into the intermediate shaft passage 99 along its path. As a result, oil O is supplied to the fifth passage 96A, the sixth passage 96B, and the intermediate shaft passage 99.

[0075] The oil O passing through the fifth channel 96A passes inside the second supply pipe 68B. The second supply pipe 68B is a hollow tubular shape extending approximately axially. The second supply pipe 68B connects the inside of the partition wall 61c to the motor cover 63. The second supply pipe 68B is located approximately above the motor 2 inside the motor housing 81. In the fifth channel 96A, the oil O flows axially along approximately above the motor 2.

[0076] The second supply pipe 68B is provided with an injection hole (not shown) that opens towards the motor 2. Therefore, in the fifth flow path 96A, the oil O is injected into the motor 2 through the injection hole, and, similar to the oil O injected into the motor 2 in the third flow path 94 described above, the oil O cools the entire motor 2, then accumulates at the bottom 81a of the motor housing 81, and returns to the oil reservoir P through the partition hole (not shown).

[0077] The sixth passage 96B is connected to the fourth passage 95 and the seventh passage 97. The oil O flowing through the sixth passage 96B passes inside the third supply pipe 68C. The third supply pipe 68C is a hollow tube extending approximately axially. The third supply pipe 68C is connected to the inside of the partition wall 61c and the inside of the gear cover 62. The third supply pipe 68C is located approximately above the transmission mechanism 3 inside the transmission mechanism housing 82. The oil O supplied to the sixth passage 96B flows axially along approximately above the transmission mechanism 3.

[0078] The third supply pipe 68C is provided with an injection hole (not shown) that opens towards the transmission mechanism 3. Therefore, in the sixth flow path 96B, a portion of the oil O diffuses into the transmission mechanism housing 82 through the injection hole. The oil O diffused into the transmission mechanism housing 82 is supplied to the tooth surfaces of each gear in the transmission mechanism 3, lubricating each gear. Furthermore, the oil O drips from the transmission mechanism 3 back into the oil reservoir P. A portion of the oil O supplied to the sixth flow path 96B reaches the seventh flow path 97.

[0079] The seventh passage 97 is connected to the sixth passage 96B, the second shaft passage 98B, and the intermediate shaft passage 99. The oil O flowing through the seventh passage 97 passes inside the gear cover 62. In other words, the oil O flowing through the oil passage 90 passes through the transmission mechanism housing 82. One end of the seventh passage 97 is connected to the second shaft passage 98B. The seventh passage 97 branches off to the intermediate shaft passage 99 along its path. As a result, the oil O is supplied to the second shaft passage 98B and the intermediate shaft passage 99.

[0080] The second shaft internal passage 98B is connected to the seventh passage 97 and the first shaft internal passage 98A. The oil O flowing through the second shaft internal passage 98B passes through the inside of the second shaft 21B. As described above, the second shaft 21B is a hollow cylindrical shape extending in the axial direction. The second shaft 21B is connected to the first shaft 21A inside the gear cover 62 and inside the partition wall 61c. The second shaft internal passage 98B is an axially extending passage inside the transmission mechanism housing 82. The oil O is supplied to the first shaft internal passage 98A.

[0081] The first shaft internal passage 98A is connected to the motor housing internal passage 93 and the second shaft internal passage 98B. The oil O flowing through the first shaft internal passage 98A passes through the inside of the first shaft 21A. As described above, the first shaft 21A is a hollow cylindrical shape extending in the axial direction. The first shaft 21A is connected to the inside of the motor cover 63 and the second shaft 21B. The first shaft internal passage 98A is an axially extending passage inside the motor housing 81. Oil O is supplied to the first shaft internal passage 98A from the motor housing internal passage 93 and the second shaft internal passage 98B.

[0082] The first shaft 21A is provided with a communication hole (not shown) that opens radially outward. In the first shaft internal passage 98A, centrifugal force is applied to the oil O as the first shaft 21A rotates. As a result, the oil O is scattered radially outward from the first shaft 21A through the communication hole. Similar to the oil O injected into the motor 2 in the third passage 94 described above, the oil O scattered from the first shaft 21A cools the entire motor 2, then accumulates at the bottom 81a of the motor housing 81, and returns to the oil reservoir P through a partition hole (not shown). In addition, as the oil O is scattered, the first shaft internal passage 98A becomes negative pressure, so the oil O in the motor housing internal passage 93 and the second shaft internal passage 98B is drawn into the first shaft 21A, and the oil O flows into the first shaft internal passage 98A.

[0083] The intermediate shaft internal passage 99 connects to the seventh passage 97 and the fourth passage 95. The oil O flowing through the intermediate shaft internal passage 99 passes through the inside of the intermediate shaft 45. As described above, the intermediate shaft 45 is a hollow cylindrical shape extending in the axial direction. The intermediate shaft 45 is connected to the inside of the gear cover 62 and the inside of the partition wall 61c via bearings. The intermediate shaft internal passage 99 is an axially extending passage inside the transmission mechanism housing 82.

[0084] As shown in Figure 1, a portion of the ring gear 51 is submerged in the oil reservoir P. Therefore, when the drive unit 1 is driven, the oil O accumulated in the oil reservoir P is stirred up by the ring gear 51 due to the operation of the transmission mechanism 3 and diffused into the transmission mechanism housing 82. The oil O diffused into the transmission mechanism housing 82 is supplied to each gear of the transmission mechanism 3, spreading the oil O over the gear teeth. The oil O supplied to the transmission mechanism 3 drips back into the oil reservoir P.

[0085] <Inverter> The inverter 7 is electrically connected to the motor 2. The inverter 7 controls the current supplied to the motor 2. As shown in Figure 3, the inverter 7 is housed in the inverter housing 84. The inverter 7 has at least one control board (not shown), a first electronic component 7a, and a second electronic component 7b. The control board is plate-shaped. The control board is fixed, for example, to the bottom 64c of the box-shaped part 64b. The control board is positioned approximately parallel to the bottom 64c. The control board holds the first electronic component 7a and the second electronic component 7b.

[0086] The first electronic component 7a is an electronic component such as a transistor. The second electronic component 7b is an electronic component such as a capacitor. In this embodiment, the second electronic component 7b has a larger vertical dimension than the first electronic component 7a. That is, the second electronic component 7b has a larger circumferential dimension than the first electronic component 7a. The first electronic component 7a is placed in the first region 64d, and the second electronic component 7b is placed in the second region 64e. As described above, the circumferential dimension of the second region 64e is larger than the circumferential dimension of the first region 64d. In other words, the first electronic component 7a, which has a smaller circumferential dimension, is placed in the first region 64d, which has a smaller circumferential dimension, and the second electronic component 7b, which has a larger circumferential dimension, is placed in the second region 64e, which has a larger circumferential dimension. This makes it possible to place the upper end of the first electronic component 7a and the upper end of the second electronic component 7b at approximately the same position. Therefore, according to this embodiment, it is possible to suppress the circumferential increase of the inverter housing 84. Consequently, it is possible to suppress an increase in the axial projected area of ​​the drive device 1, and to miniaturize the entire drive device 1.

[0087] Furthermore, the second electronic component 7b is positioned above the output shaft J3 and the pump 8. In other words, the second electronic component 7b, the output shaft J3, and the pump 8 are arranged side by side in the circumferential direction. In this embodiment, the second electronic component 7b, the output shaft J3, and the pump 8 are arranged side by side in the vertical direction. The upper end of the output shaft 55 is located below the upper end of the motor housing 81. The lower end of the output shaft 55 is located above the lower end of the motor housing 81. Therefore, according to this embodiment, by positioning the second electronic component 7b, which has a large vertical dimension, above the output shaft 55, and positioning the pump 8 below the output shaft 55, the inverter 7, the output shaft 55, and the pump 8 can be compactly arranged in the vertical direction. This suppresses an increase in the radial and axial projected area of ​​the drive unit 1, and makes the overall drive unit 1 smaller.

[0088] In this embodiment, it has been described that one first electronic component 7a is placed in the first region 64d and one second electronic component 7b is placed in the second region 64e. However, in addition to the first electronic component 7a, another electronic component having a smaller circumferential dimension than the first electronic component may be placed in the first region 64d. Similarly, in addition to the second electronic component 7b, another electronic component having a smaller circumferential dimension than the second electronic component 7b may be placed in the second region 64e. That is, the first electronic component 7a should be the component with the largest circumferential dimension (vertical dimension in this embodiment) among the electronic components provided in the first region 64d. Similarly, the second electronic component should be the component with the largest circumferential dimension (vertical dimension in this embodiment) among the electronic components provided in the second region 64e.

[0089] <Refrigerant flow path> As shown in Figure 1, the refrigerant passage 70 is provided in the housing 6. The refrigerant passage 70 spans the motor housing 81, the support section 83, and the inverter housing 84. The refrigerant passage 70 is the path through which the refrigerant L, cooled by the radiator (not shown), flows. The refrigerant L flows from the radiator, through the inverter housing 84, the motor housing 81, the support section 83, and the cooler 9, and back to the radiator. In other words, the drive unit 1 is equipped with a refrigerant passage 70 through which the refrigerant L flows. The refrigerant L flowing through the refrigerant passage 70 cools the inverter 7 in the inverter housing 84. Also, as described above, the refrigerant L flowing through the refrigerant passage 70 exchanges heat with the oil O inside the cooler 9 to cool the oil O. In this embodiment, the refrigerant L is water.

[0090] The refrigerant flow path 70 includes an inverter housing refrigerant flow path 71, a first refrigerant flow path 72, a connecting refrigerant flow path 73, a cooler housing refrigerant flow path 74, an outlet refrigerant flow path 75, piping (not shown), and external piping 69. In this embodiment, the inverter housing refrigerant flow path 71, the first refrigerant flow path 72, the connecting refrigerant flow path 73, and the outlet refrigerant flow path 75 are provided inside the wall of the housing 6. Therefore, there is no need to prepare separate piping materials to provide these flow paths, which contributes to reducing the number of parts.

[0091] As shown in Figure 1, the refrigerant passage 71 inside the inverter housing is connected to a pipe (not shown) and a first refrigerant passage 72. The refrigerant L flowing through the refrigerant passage 71 inside the inverter housing passes through the inside of the inverter cover 64. In other words, the refrigerant L flowing through the refrigerant passage 71 inside the inverter housing passes through the inverter housing 84. As a result, the refrigerant L flowing through the refrigerant passage 71 inside the inverter housing cools the inverter 7 via the inverter cover 64. The refrigerant passage 71 inside the inverter housing extends in one axial direction. As shown in Figure 2, an opening 64f is provided at one end of the refrigerant passage 71 inside the inverter housing. A pipe (not shown) is connected to the opening 64f. The refrigerant passage 71 inside the inverter housing is connected to a radiator (not shown) via the pipe. As a result, the refrigerant L cooled by the radiator is supplied to the refrigerant passage 71 inside the inverter housing.

[0092] As shown in Figure 1, the first refrigerant flow path 72 is connected to the inverter housing refrigerant flow path 71 and the connected refrigerant flow path 73. The refrigerant L flowing through the first refrigerant flow path 72 passes through the inside of the inverter housing 84 and the support section 83. The first refrigerant flow path 72 extends in a substantially vertical direction.

[0093] The connecting refrigerant passage 73 connects to the first refrigerant passage 72 and the cooler internal refrigerant passage 74. The refrigerant L flowing through the connecting refrigerant passage 73 passes inside the support section 83. One end of the connecting refrigerant passage 73 is connected to the refrigerant inlet 9c of the cooler 9. This connects the connecting refrigerant passage 73 and the cooler internal refrigerant passage 74. The connecting refrigerant passage 73 extends inside the support section 83 toward the rear side of the vehicle (+X direction). In this embodiment, the connecting refrigerant passage 73 extends in a straight line. The connecting refrigerant passage 73 and the connecting passage 92a extend parallel to each other inside the wall of the housing 6. That is, the connecting refrigerant passage 73 and the connecting passage 92a extending inside the support section 83 of the housing 6 are parallel to each other and extend in the same direction. Therefore, according to this embodiment, for example, when providing the connecting refrigerant passage 73 and the connecting passage 92a in the housing 6 by machining such as drilling, after providing either the connecting refrigerant passage 73 or the connecting passage 92a, the other can be provided by moving the drill in parallel without changing its position. Thus, an increase in the machining time for the housing 6 can be suppressed. In other words, the manufacturing time for the drive unit 1 can be suppressed.

[0094] The cooler internal refrigerant flow path 74 is connected to the connecting refrigerant flow path 73 and the outlet refrigerant flow path 75. The cooler internal refrigerant flow path 74 is provided inside the cooler 9. In other words, the cooler 9 is provided with the cooler internal refrigerant flow path 74 through which the refrigerant L passes. As shown in Figures 1 and 4, the cooler internal refrigerant flow path 74 and the connecting refrigerant flow path 73 are connected via the refrigerant inlet 9c of the cooler 9. The cooler internal refrigerant flow path 74 and the outlet refrigerant flow path 75 are connected via the refrigerant outlet 9d of the cooler 9. The cooler internal refrigerant flow path 74 is connected to the refrigerant inlet 9c and the refrigerant outlet 9d. In other words, the cooler 9 has a refrigerant inlet 9c through which the refrigerant L flows in and a refrigerant outlet 9d through which the refrigerant L flows out. As shown in Figure 3, viewed in the axial direction, the cooler internal refrigerant flow path 74 extends in the circumferential direction of the output shaft J3. Furthermore, as described above, when viewed in the axial direction, the cooler internal passage 91c extends in the circumferential direction of the output shaft J3. The cooler internal refrigerant passage 74 is arranged to overlap with the cooler internal passage 91c and the output shaft J3 in the radial direction of the motor shaft J1. Therefore, according to this embodiment, the cooler internal passage 91c, the cooler internal refrigerant passage 74, and the output shaft 55 are unlikely to interfere with each other, and the cooler 9 can be positioned close to the output shaft 55. Thus, the cooler 9 can be positioned close to the output shaft 55 in the radial direction. Consequently, the overall size of the drive unit 1 can be reduced in the radial direction.

[0095] Furthermore, as shown in Figure 4, the refrigerant inlet 9c is located above the output shaft J3. The refrigerant outlet 9d is located below the output shaft J3. In the vertical direction, the output shaft J3 is positioned between the refrigerant inlet 9c and the refrigerant outlet 9d. In other words, in the circumferential direction, the output shaft J3 is positioned between the refrigerant inlet 9c and the refrigerant outlet 9d. Therefore, according to this embodiment, the cooler 9 is positioned radially outward with respect to the output shaft 55. As a result, the lower end of the cooler 9 can be positioned above the lower end of the motor housing 81 and the lower end of the transmission mechanism housing 82. Consequently, the drive unit 1 can be miniaturized in the vertical direction.

[0096] As shown in Figure 1, the outlet refrigerant flow path 75 connects to the cooler's internal refrigerant flow path 74 and the external piping 69. The outlet refrigerant flow path 75 is a flow path that extends axially through the support portion 83. In this embodiment, the outlet refrigerant flow path 75 is linear. That is, the refrigerant flow path 70 has an outlet refrigerant flow path 75 that extends from the refrigerant outlet 9d through the wall of the housing 6. An opening 75a is provided at one end of the outlet refrigerant flow path 75. One end of the external piping 69 is connected to the opening 75a. The other end of the external piping 69 is connected to a radiator (not shown). As shown in Figure 4, the direction in which the opening 75a of the outlet refrigerant flow path 75 faces is parallel to the output shaft J3. Therefore, according to this embodiment, as shown in Figure 2, when attaching the external piping 69 to the drive unit 1, the output shaft 55 can be easily avoided and the external piping 69 can be connected to the opening 75a from the other axial side. Thus, the work of attaching the external piping 69 to the drive unit 1 can be simplified. Furthermore, according to this embodiment, the opening 75a is located on the rear side (+X direction side) of the vehicle relative to the output shaft 55 and the pump 8. Therefore, the position of the opening 75a can be easily seen from outside the drive unit 1, and the work of attaching the external piping 69 to the drive unit 1 can be further simplified.

[0097] According to this embodiment, the housing 6 includes a motor housing 81, a transmission mechanism housing 82 located on one axial side of the motor housing 81, an inverter housing 84, and a support portion 83 located radially outside the motor housing 81 and on one circumferential side of the inverter housing 84 when viewed from the axial direction, and connected to the outer periphery of the motor housing 81 and the bottom of the inverter housing 84. Therefore, the support portion 83 can be provided in the aforementioned dead space formed between the motor housing 81, the transmission mechanism housing 82, and the inverter housing 84. Furthermore, the support portion 83 supports the pump 8 and the cooler 9, with either the pump 8 or the cooler 9 positioned circumferentially on one side of the support portion 83 when viewed from the axial direction, and the other positioned radially outside the support portion 83. Therefore, the pump 8 and the cooler 9 can be provided in the dead space. Consequently, the overall size of the drive unit 1 can be reduced.

[0098] Furthermore, in this embodiment, the support portion 83 is connected to the outer periphery of the motor housing portion 81, and the pump 8 and cooler 9 are supported by the support portion 83. Therefore, the oil passage 90 connecting the motor housing portion 81, the pump 8, and the cooler 9 can be shortened via the support portion 83. Consequently, pressure loss in the oil passage 90 can be reduced, and efficient circulation of oil O can be achieved when the drive unit 1 is driven. In addition, the support portion 83 is connected to the outer periphery of the motor housing portion 81 and the bottom of the inverter housing portion 84, and the cooler 9 is supported by the support portion 83. Therefore, the refrigerant passage 70 connecting the motor housing portion 81, the inverter housing portion 84, and the cooler 9 can be shortened via the support portion 83. Consequently, pressure loss in the refrigerant passage 70 can be reduced, and efficient circulation of refrigerant L can be achieved when the drive unit 1 is driven.

[0099] Furthermore, in this embodiment, as described above, either the pump 8 or the cooler 9 is positioned on one side in the circumferential direction relative to the support portion 83 when viewed from the axial direction, while the other is positioned radially outward relative to the support portion 83. In other words, the pump 8 and the cooler 9 are positioned in different directions relative to the support portion 83. Therefore, in this embodiment, the oil passage connected to the pump 8, the oil passage connected to the pump 8 and the cooler 9, and the cooling passage connected to the cooler 9, which are provided inside the support portion 83, can be easily provided in a linear manner. More specifically, in this embodiment, the first passage 91a, the second passage 91b, the connecting passage 92a, the connecting refrigerant passage 73, and the outlet-side refrigerant passage 75 are provided in a linear manner. Therefore, the pressure loss in the oil passage 90 and the refrigerant passage 70 can be further reduced, and more efficient circulation of oil O and refrigerant L can be achieved.

[0100] According to this embodiment, the support portion 83 is located on the other axial side of the transmission mechanism housing portion 82 and is connected to the transmission mechanism housing portion 82. That is, the support portion 83 is connected to both the motor housing portion 81 and the transmission mechanism housing portion 82. Therefore, the oil passage 90 connecting the motor housing portion 81, the transmission mechanism housing portion 82, the pump 8, and the cooler 9 can be shortened via the support portion 83. Consequently, pressure loss in the oil passage 90 can be reduced, and efficient circulation of oil O can be achieved.

[0101] In this embodiment, the pump 8 is positioned on one side in the circumferential direction relative to the support portion 83 when viewed from the axial direction. In this embodiment, the pump 8 is positioned below the support portion 83. The cooler 9 is positioned radially outward relative to the support portion 83 when viewed from the axial direction. In this embodiment, the cooler 9 is positioned on the rear side (+X direction side) of the support portion 83. In other words, the pump 8 and the cooler 9 are positioned in different directions relative to the support portion 83. Therefore, the support portion 83, the pump 8, and the cooler 9 can be arranged compactly, and each of the support portion 83, the pump 8, and the cooler 9 can be placed in dead space. Thus, the overall size of the drive unit 1 can be reduced.

[0102] Furthermore, in this embodiment, the pump 8 can be positioned near the oil reservoir P located in the lower region of the transmission mechanism housing 82. Therefore, the first flow path 91a connecting the oil reservoir P and the pump 8 can be shortened. Also, the first flow path 91a can be, for example, a straight flow path. As a result, pressure loss in the first flow path 91a can be reduced, and efficient circulation of oil O can be achieved. In addition, according to this embodiment, the suction port 8c of the pump 8 is located on one side in the axial direction. Therefore, the suction port 8c can be positioned near the oil reservoir P, and the first flow path 91a connecting the oil reservoir P and the suction port 8c can be shortened even further. As a result, pressure loss in the path from the oil reservoir P to the pump 8 can be further reduced, and more efficient circulation of oil O can be achieved.

[0103] According to this embodiment, the transmission mechanism 3 has an output shaft 55 centered on an output shaft J3 parallel to the motor shaft J1, and the output shaft 55 passes through the support portion 83. In other words, in the dead space, the support portion 83 is provided surrounding the output shaft 55. Therefore, the support portion 83 can be connected to the motor housing portion 81, the transmission mechanism housing portion 82, and the inverter housing portion 84. As a result, the oil passage 90 that spans the support portion 83, the motor housing portion 81, and the transmission mechanism housing portion 82 can be shortened. Also, the refrigerant passage 70 that spans the support portion 83, the motor housing portion 81, and the inverter housing portion 84 can be shortened. Therefore, pressure loss in the oil passage 90 and the refrigerant passage 70 can be further reduced, and more efficient circulation of oil O and refrigerant L can be achieved.

[0104] Furthermore, the arrangement of the pump and cooler can be any arrangement as long as they can be placed in dead space. For example, the pump may be placed radially outward from the support and the cooler may be placed on one circumferential side of the support. Alternatively, both the pump and cooler may be placed on one circumferential side of the support, or radially outward from the support.

[0105] The pump does not have to be electric, as long as it can pump oil into the oil passages. For example, a mechanical pump may be used. In this case, the pump drive unit is connected to the output shaft via a coupling mechanism such as gears, and the pump can be driven by the rotation of the output shaft.

[0106] The flow path is not limited to the configuration of this embodiment, as long as it can cool the motor. For example, the third flow path, the fifth flow path, or the second shaft internal flow path may not be provided. Additionally, a separate flow path for supplying fluid to the motor may be added. Furthermore, the refrigerant flow path is not limited to the configuration of this embodiment, as long as it can cool the inverter and the fluid. Two or more pumps and coolers may be provided.

[0107] Although embodiments of the present invention have been described above, the configurations and combinations thereof in the embodiments are merely examples, and additions, omissions, substitutions, and other modifications are possible without departing from the spirit of the present invention. Furthermore, the present invention is not limited by the embodiments. [Explanation of symbols]

[0108] 1…Drive unit, 2…Motor, 3…Transmission mechanism, 6…Housing, 7…Inverter, 7a…First electronic component, 7b…Second electronic component, 8…Pump, 8b…Pump motor, 9…Cooler, 9c…Refrigerant inlet, 9d…Refrigerant outlet, 20…Rotor, 21…Shaft, 30…Stator, 41,42,43,51…Gears, 55…Output shaft, 64c…Bottom, 64d…First region, 64e…Second region, 69…External piping, 70…Refrigerant flow path, 71…Inlet Refrigerant passage within inverter housing, 73...connecting refrigerant passage, 74...refrigerant passage within cooler, 75...outlet refrigerant passage, 75a...opening, 81...motor housing, 82...transmission mechanism housing, 83...support section, 84...inverter housing, 90...flow path (oil passage), 91c...flow path within cooler, 92a...connecting passage, 93...flow path within motor housing, 8...pump, 8b...pump motor, J1...motor shaft, J3...output shaft, J4...rotating shaft, L...refrigerant (water), O...fluid (oil)

Claims

1. A motor having a rotor that rotates around a motor shaft, and a stator that surrounds the rotor, A transmission mechanism having multiple gears that transmits power from the motor, An inverter that controls the current supplied to the motor, A housing that houses the motor, the transmission mechanism, and the inverter, The fluid contained within the housing, A channel through which the aforementioned fluid flows, At a minimum, a refrigerant for cooling the inverter, A refrigerant flow path through which the aforementioned refrigerant flows, A pump for pumping the fluid in the aforementioned flow path, A cooler that exchanges heat between the fluid and the refrigerant, Equipped with, The aforementioned housing is A motor housing section for housing the motor, A transmission mechanism housing is located on one axial side of the motor housing and houses the transmission mechanism, An inverter housing section for housing the inverter, A support portion located radially outward of the motor housing and below the inverter housing in the vertical direction when viewed from the axial direction, and connected to at least one of the outer periphery of the motor housing or the bottom of the inverter housing, It has, The support portion supports at least one of the pump or the cooler, The transmission mechanism has an output shaft centered on an output shaft parallel to the motor shaft, A drive device in which at least a portion of the support portion overlaps the output shaft in the vertical direction.

2. The drive device according to claim 1, wherein the support portion is connected to both the outer periphery of the motor housing and the bottom of the inverter housing.

3. The drive device according to claim 1 or 2, wherein either the pump or the cooler is positioned below the support in the vertical direction when viewed from the axial direction, and the other is positioned radially outward with respect to the support.

4. The drive device according to any one of claims 1 to 3, wherein the support portion is located on the other axial side of the transmission mechanism housing portion and is connected to the transmission mechanism housing portion.

5. The pump is positioned below the support portion in the vertical direction when viewed from the axial direction. The drive device according to any one of claims 1 to 4, wherein the cooler is arranged radially outward with respect to the support when viewed from the axial direction.

6. The drive device according to any one of claims 1 to 5, wherein the support portion is located between the cooler and the motor housing portion in a direction perpendicular to both the axial and vertical directions.

7. In the axial direction and in a direction perpendicular to the vertical direction, the pump is arranged alongside the motor housing, as described in any one of claims 1 to 6.

8. The drive device according to any one of claims 1 to 7, wherein the output shaft is located between the cooler and the motor housing in a direction perpendicular to the axial direction and the vertical direction.

9. The drive device according to any one of claims 1 to 8, wherein in the vertical direction, the output shaft is located between the inverter housing and the pump.

10. The drive device according to any one of claims 1 to 9, wherein the output shaft penetrates the support portion.

11. The cooler has a refrigerant inlet through which the refrigerant flows in, and a refrigerant outlet through which the refrigerant flows out. The drive device according to any one of claims 1 to 10, wherein in the vertical direction, the output shaft is positioned between the refrigerant inlet and the refrigerant outlet.

12. The cooler is provided with an internal cooler passage through which the fluid passes, and an internal cooler refrigerant passage through which the refrigerant passes. In the radial direction of the motor shaft, the cooler internal flow path, the cooler internal refrigerant flow path, and the output shaft are arranged to overlap. The drive device according to any one of claims 1 to 11, wherein, viewed in the axial direction, the internal flow path of the cooler and the internal refrigerant flow path of the cooler extend in the circumferential direction of the output shaft.

13. The refrigerant flow path is An outflow-side refrigerant flow path extending from the refrigerant outlet and provided within the wall of the housing, External piping connected to the opening of the outlet side refrigerant flow path, It has, The drive device according to claim 11, wherein the direction in which the opening of the outflow side refrigerant flow path faces is parallel to the output shaft.

14. The refrigerant flow path is A refrigerant flow path is provided in the inverter housing for cooling the inverter, A connecting refrigerant flow path between the refrigerant flow path inside the inverter housing and the cooler, It has, The aforementioned flow path is A motor housing section is provided with an internal flow path within the motor housing section, A connecting channel that connects the motor housing internal channel and the cooler, It has, The drive device according to any one of claims 1 to 13, wherein the connecting refrigerant flow path and the connecting flow path extend parallel to each other within the wall of the housing.

15. The pump has a pump motor that rotates around a rotation axis parallel to the motor shaft, The drive device according to any one of claims 1 to 14, wherein the rotating shaft is located below each of the axes in the vertical direction of the motor and the plurality of shafts of the transmission mechanism.

16. The drive device according to any one of claims 1 to 15, wherein in the vertical direction, the lower ends of the pump and the cooler are located above the lower end of the motor housing and the lower end of the transmission mechanism housing.

17. The drive device according to any one of claims 1 to 16, wherein the pump and the cooler overlap the inverter housing in the vertical direction.

18. The pump and the cooler are located radially outward from the motor housing, The drive device according to claim 17, wherein the pump and the cooler are arranged in the circumferential direction of the output shaft.

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