Electric vehicle driving device

Abstract

To obtain an electric vehicle driving device that does not require piping around an oil cooler, decreases weight and size, prevents the invasion of cooling water into a waterproof zone, and facilitates assembling to an electric vehicle.SOLUTION: An electric vehicle driving device is equipped with a motor, a gear box that stores a deceleration mechanism coupled with the motor and a differential mechanism coupled with the deceleration mechanism, an inverter that is electrically connected to the motor to convert power, and an oil cooler that oil-cools the motor. The inverter has a first cooling water path and a second cooling water path in which cooling water flows. The oil cooler has an oil cooler water path in which the cooling water flows. The oil cooler is provided so as to abut on the inverter. At the abutting part, a water path is formed, in which the first cooling water path and the oil cooler water path are coupled, the second cooling water path and the oil cooler water path are coupled, and the cooling water flows in the order of the first cooling water path, the oil cooler water path, and the second cooling water path.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to an electric vehicle drive device. [Background technology]

[0002] In recent years, vehicles powered by internal combustion engines that are supplied with fuel from a fuel tank are being rapidly replaced by electric vehicles powered by motors that are supplied with electricity from a battery. In addition, the integration of on-board devices for driving electric vehicles is also progressing. Electric vehicle drive devices for driving electric vehicles are often configured by integrating a motor that generates power, a reduction gear that reduces the speed of the motor and transmits the power to the axles, and an inverter that converts a direct current stored in a battery into an arbitrary alternating current to efficiently drive and control the motor. Each of the motor, the reduction gear, and the inverter generates losses during energy conversion or power transmission. Heat generated by the losses increases the local temperature of each device. An excessive increase in the local temperature of each device can cause a breakdown of the electric vehicle drive device. Therefore, it is necessary to properly cool the electric vehicle drive device.

[0003] A typical cooling configuration for cooling an electric vehicle drive device is composed of an oil cooling system in which oil circulates inside the electric vehicle drive device, and an external water cooling system in which cooling water is supplied from the outside to an oil cooler, which is part of the oil cooling system (for example, Patent Document 1). In the oil cooling system, oil that is retained in the lower part of a housing that accommodates a reduction gear is supplied to a heat generating part via an oil cooler by an oil pump and one or more oil passages. When the heat generating part comes into contact with the oil directly or indirectly, the oil absorbs heat and cools the heat generating part, and the hot oil flows back to the lower part of the housing. The external water cooling system is composed of a radiator, a cooling water pump, a water-cooled plate of an inverter, and an oil cooler, all connected by piping. The cooling water in the external water cooling system is circulated by operating the cooling water pump.

[0004] With this configuration, cooling water is supplied from the external water-cooling system to the oil cooler, and the high-temperature oil circulating in the oil-cooling system exchanges heat with the cooling water in the oil cooler, allowing the low-temperature oil to be supplied to the heat-generating parts. Meanwhile, in the external water-cooling system, the cooling water absorbs heat from the high-temperature oil in the oil cooler, and the high-temperature cooling water dissipates heat to the surrounding air in the radiator. The low-temperature cooling water sent from the radiator is supplied again to the oil cooler. In the oil circulation of the oil-cooling system and the cooling water circulation of the external water-cooling system, heat is transported from the heat-generating parts of the electric vehicle drive device to the radiator via the oil and cooling water, and the heat is dissipated from the radiator to the surrounding air.

[0005] A specific configuration of a portion of an electric vehicle drive device where an oil cooler is provided has been disclosed (for example, Patent Document 2). In the disclosed configuration of the electric vehicle drive device, a rectangular parallelepiped oil cooler in which oil passages and cooling water passages are alternately stacked is provided diagonally above the motor to enable efficient heat exchange. Two oil passage connection parts are provided on the surface where the motor and the oil cooler are in contact. Two L-shaped nipples are attached to the opposite surface of the oil cooler, and a hose for passing cooling water is connected to the nipple, forming a pipe through which the cooling water flows. With this configuration, cooling water can be passed through the hose pipe, and oil can be supplied from the oil passage connection part by a separately provided oil pump, and heat exchange between the oil and the cooling water can be efficiently performed through a solid wall in the oil cooler that separates the oil passage and the cooling water passage. Through heat exchange, low-temperature oil is sent out from the oil passage connection part of the oil cooler, and the low-temperature oil is supplied to a heat-generating part of the electric vehicle drive device, thereby cooling the heat-generating part.

[0006] Another specific configuration of the portion of an electric vehicle drive device where an oil cooler is provided has been disclosed (for example, Patent Document 3). In the disclosed configuration of the electric vehicle drive device, the oil cooler is housed in a gear box that houses the reduction mechanism and the differential mechanism. With this configuration, there is no protruding portion of the oil cooler itself in the electric vehicle drive device, so the electric vehicle drive device can be made smaller. In addition, the electric vehicle drive device can be easily incorporated into the electric vehicle. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent No. 7140727 [Patent Document 2] Patent No. 7278845 [Patent Document 3] JP 2000-295818 A Summary of the Invention [Problem to be solved by the invention]

[0008] In the above Patent Document 2, the oil and the cooling water can efficiently exchange heat in the oil cooler, and the low-temperature oil sent from the oil passage connection part of the oil cooler can cool the heat-generating parts of the electric vehicle drive device. However, in the electric vehicle drive device, the oil cooler is attached in a protruding configuration, the nipple for the cooling water protrudes further, and space is required around the nipple to route the hose piping, so the volumetric efficiency of the electric vehicle drive device is very poor, which causes the electric vehicle drive device to become large, which is a problem. In addition, there is a problem that the electric vehicle drive device cannot be easily installed in the electric vehicle.

[0009] In the above Patent Document 3, since the oil cooler is housed in the gear box, the electric vehicle drive device is miniaturized and can be easily incorporated into the electric vehicle. However, although the protruding part of the oil cooler itself is eliminated, the nipple for the cooling water protrudes around the oil cooler, and a space is required around the oil cooler to route the hose, which is a pipe, so that the volume efficiency of the electric vehicle drive device is poor, and there is a problem that the electric vehicle drive device becomes large. In addition, although the inside of the gear box needs to be waterproofed to prevent rust from occurring in the constituent members, in the above Patent Document 3, since the cooling water passage is housed in the gear box, there is a problem that the cooling water enters the inside of the gear box, which is the waterproof compartment of the electric vehicle drive device. If the cooling water enters the inside of the gear box, the inside of the gear box may rust. In addition, because the gearbox does not have a drainage function from the inside to the outside, there is a possibility that cooling water may enter the inside of the motor. If cooling water enters the inside of the motor, there is a risk that the cooling water may cause insulation breakdown in the wiring connections and stator coils inside the motor, resulting in a larger malfunction of the electric vehicle drive device.

[0010] Therefore, an object of the present disclosure is to obtain an electric vehicle drive device that does not require piping around the oil cooler, is lightweight and compact, does not allow cooling water to enter the waterproof compartment, and can be easily incorporated into an electric vehicle. [Means for solving the problem]

[0011] The electric vehicle drive device disclosed herein includes a motor, a gearbox that houses a reduction mechanism connected to the motor and a differential mechanism connected to the reduction mechanism, an inverter electrically connected to the motor and converts electric power, and an oil cooler that oil-cools the motor, wherein the inverter has a first cooling water passage and a second cooling water passage through which cooling water flows, and the oil cooler has an oil cooler water passage through which the cooling water flows, and the oil cooler is arranged in abutment against the inverter, and at the abutment portion, the first cooling water passage and the oil cooler water passage are connected, and the second cooling water passage and the oil cooler water passage are connected, forming water passages through which cooling water flows in the order of the first cooling water passage, the oil cooler water passage, and the second cooling water passage. Effect of the Invention

[0012] According to the electric vehicle drive device of the present disclosure, the inverter has a first cooling water passage and a second cooling water passage through which the cooling water flows, the oil cooler has an oil cooler water passage through which the cooling water flows, and the oil cooler is provided in contact with the inverter, and the first cooling water passage and the oil cooler water passage are connected at the contact portion, and the second cooling water passage and the oil cooler water passage are connected, and the cooling water flows in the order of the first cooling water passage, the oil cooler water passage, and the second cooling water passage. Therefore, since no piping is required around the oil cooler, particularly between the inverter and the oil cooler, for the water passage through which the cooling water flows, the electric vehicle drive device can be made lighter and smaller. Furthermore, since no water passage through which the cooling water flows is provided inside the gear box, which is a waterproof compartment of the electric vehicle drive device, the intrusion of the cooling water into the waterproof compartment can be suppressed. Furthermore, since no piping is provided around the oil cooler, there is no protruding portion of the piping around the oil cooler, and therefore no troublesome piping work and no space for handling the piping are required, and an electric vehicle drive device that is easy to install in an electric vehicle can be obtained. [Brief description of the drawings]

[0013] [Figure 1] 1 is a plan view showing an outline of an electric vehicle driving device according to a first embodiment. [Diagram 2] 1 is a front view showing an outline of an electric vehicle driving device according to a first embodiment. [Diagram 3] 1 is a side view showing an outline of an electric vehicle driving device according to a first embodiment. [Figure 4] 1 is an exploded plan view showing a main part of an electric vehicle driving device according to a first embodiment. [Diagram 5] 1 is a side view showing a main part of an electric vehicle driving device according to a first embodiment. [Figure 6] 4 is an exploded plan view showing a main part of another electric vehicle driving device according to the first embodiment. FIG. [Figure 7] 4 is a side view showing a main part of another electric vehicle driving device according to the first embodiment. FIG. [Figure 8] 4 is an exploded plan view showing a main part of another electric vehicle driving device according to the first embodiment. FIG. [Figure 9] 4 is a side view showing a main part of another electric vehicle driving device according to the first embodiment. FIG. [Figure 10] 11 is a side view showing a main part of an electric vehicle driving device according to a second embodiment. FIG. [Figure 11] 11 is a plan view showing a main part of an electric vehicle driving device according to a second embodiment. FIG. [Figure 12] FIG. 11 is a side view showing a main part of an electric vehicle driving device according to a third embodiment. [Figure 13] FIG. 11 is a plan view showing a main part of an electric vehicle driving device according to a third embodiment. [Figure 14] FIG. 11 is a cross-sectional view showing a main part of an electric vehicle driving device according to a fourth embodiment. [Figure 15] FIG. 11 is a cross-sectional view showing a main part of another electric vehicle driving device according to the fourth embodiment. [Figure 16] FIG. 11 is a cross-sectional view showing a main part of another electric vehicle driving device according to the fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, an electric vehicle drive device according to an embodiment of the present disclosure will be described with reference to the drawings. Note that the same or equivalent members and parts in each drawing will be described with the same reference numerals. Note that the electric vehicle in this disclosure is not limited to automobiles, but refers to mobility used for transportation, transport, and moving means, including motorcycles.

[0015] Embodiment 1 FIG. 1(a) is a plan view showing an outline of an electric vehicle drive device 1 according to a first embodiment, FIG. 1(b) is a plan view showing an outline of the electric vehicle drive device 1 with a drive shaft 6a removed from the electric vehicle drive device 1, FIG. 1(c) is a plan view showing an outline of another electric vehicle drive device 1, FIG. 2 is a front view showing an outline of the electric vehicle drive device 1, as viewed from the direction of travel of the electric vehicle, FIG. 3 is a side view showing an outline of the electric vehicle drive device 1, as viewed from the other side in the X direction, FIG. 4 is an exploded plan view showing a main part of the electric vehicle drive device 1, and is a diagram showing the mounting structure of an oil cooler 2 at part A (encircled by a dashed line) in FIG. 2, and FIG. 5(a) is a side view showing a main part of the electric vehicle drive device 1, as viewed from the other side in the X direction with both the oil cooler 2 and the water-cooled plate 12 being transparent. 2, FIG. 7 is a side view of the main parts of the other electric vehicle driving device 1, as viewed from the other side in the X-direction; FIG. 8 is an exploded plan view of the main parts of the other electric vehicle driving device 1, as viewed from the other side in the X-direction; FIG. 9 is a side view of the main parts of the other electric vehicle driving device 1, as viewed from the other side in the X-direction; FIG. 10 is a side view of the main parts of the other electric vehicle driving device 1, as viewed from the other side in the X-direction; FIG. 11 is a side view of the main parts of the other electric vehicle driving device 1, as viewed from the other side in the X-direction; FIG. 12 is a side view of the main parts of the other electric vehicle driving device 1, as viewed from the other side in the X-direction; The electric vehicle drive device 1 mounted on an electric vehicle is a device that transmits rotation of a rotating shaft 3a of a motor 3 controlled by an inverter 7 to a drive shaft 6a via a reduction mechanism 4 and a differential mechanism 5.

[0016] <Electric vehicle drive unit 1> As shown in FIG. 1(b), the electric vehicle drive device 1 includes a motor 3, a gear box 6 that houses a reduction gear mechanism 4 connected to the motor 3 and a differential mechanism 5 connected to the reduction gear mechanism 4, an inverter 7 that is electrically connected to the motor 3 and converts electric power, and an oil cooler 2 that oil-cools the motor 3. Here, directions are defined. In FIG. 1(a) and FIG. 2, the direction in which the oil cooler 2 is arranged next to the inverter 7 is one side of the X direction, and in FIG. 1(a) and FIG. 3, the direction perpendicular to the X direction and in which the motor 3 is provided relative to the inverter 7 is one side of the Y direction, and the direction perpendicular to the X direction and the Y direction is the Z direction. In each figure, the direction indicated by the arrow is one side, and the opposite direction to the direction indicated by the arrow is the other side.

[0017] A gear box 6 is provided on one side of the motor 3 and the oil cooler 2 in the X direction. In this embodiment, as shown in FIG. 1(a), the motor 3 and the gear box 6 are connected in an L shape. The oil cooler 2 and the inverter 7 are provided on the other side of the Z direction of the portion between the motor 3 and the gear box 6 arranged in the L shape. The arrangement of the members in the electric vehicle drive device 1 is not limited to the above-mentioned configuration. As will be described later, it is sufficient that the oil cooler 2 is provided in contact with the inverter 7. For example, as shown in FIG. 1(c), the oil cooler 2 may be provided on one side of the inverter 7 in the Y direction and the oil cooler 2 may be sandwiched between the inverter 7 and the motor 3.

[0018] 1(b), the motor 3 includes a stator 3d having an iron core and a coil, a rotor 3b disposed inside the stator 3d, and a housing 3c accommodating the stator 3d and the rotor 3b. A rotating shaft 3a of the rotor 3b is rotatably supported by a bearing and disposed so as to rotate coaxially with the stator 3d. The housing 3c is produced, for example, by casting or forging a metal such as aluminum.

[0019] The gear box 6 houses the reduction gear mechanism 4 connected to the rotating shaft 3a, and the differential mechanism 5 connected to the reduction gear mechanism 4. The reduction gear mechanism 4 reduces the rotation of the rotating shaft 3a of the motor 3 and outputs it. The differential mechanism 5 absorbs the speed difference between the left and right tires. The gear box 6 is produced, for example, by casting or forging a metal such as aluminum.

[0020] One side of the drive shaft 6a is connected to the differential mechanism 5. The drive shaft 6a extends in the X direction. Tires (not shown) are attached to both ends of the extended drive shaft 6a. By making the housing 3c and the gear box 6 from aluminum, they can be made lighter and less expensive, and complex shapes can be easily made. Furthermore, making these parts from the same material provides a measure against electrolytic corrosion. Note that these materials are not limited to aluminum, and may be resin materials.

[0021] <Inverter 7, Oil cooler 2> The configurations of the inverter 7 and the oil cooler 2, which are essential parts of the present disclosure, will be described. The inverter 7 exchanges DC / AC between a DC power source (not shown) and the windings of the multi-phase stator 3d. The inverter 7 is fixed to the motor 3, for example. As shown in FIG. 1(b), the inverter 7 has a first cooling water passage 13a and a second cooling water passage 13b through which cooling water flows.

[0022] The oil cooler 2 has an oil cooler water passage 2a through which cooling water flows, and an oil cooler oil passage 2b through which oil flows. These are shown in FIG. 1(b) as a schematic diagram. The oil cooler water passage 2a and the oil cooler oil passage 2b are arranged separately without communicating with each other. The oil cooler 2 is an oil-cooling water heat exchanger in which the oil cooler water passage 2a and the oil cooler oil passage 2b exchange heat through a solid wall. The oil cooler water passage 2a and the oil cooler oil passage 2b are arranged in a stacked manner, for example, as shown in FIG. 4. The oil cooler 2 has an oil header 19 and a cooling water header 20 on both sides in the Y direction, as shown in FIG. 5(a). The stacked oil cooler water passage 2a part is connected to the cooling water header 20, and a flow path connected in parallel is formed. The stacked oil cooler oil passage 2b part is connected to the oil header 19, and a flow path connected in parallel is formed. The motor 3 and the gear box 6 have an oil passage 10 connected to the oil cooler oil passage 2b. The cooling water is, for example, water, but is not limited to this, and an antifreeze liquid (LLC) mainly containing ethylene glycol may also be used.

[0023] The oil cooler 2 is provided in contact with the inverter 7, as shown in FIG. 1(b). At the contact portion, the first cooling water passage 13a and the oil cooler water passage 2a are connected, and the second cooling water passage 13b and the oil cooler water passage 2a are connected. Water passages are formed through which the cooling water flows in the order of the first cooling water passage 13a, the oil cooler water passage 2a, and the second cooling water passage 13b. The portion of the inverter 7 with which the oil cooler 2 contacts is the water-cooled plate 12, which is the portion of the inverter 7 in which the first cooling water passage 13a and the second cooling water passage 13b are formed, as shown in FIG. 2.

[0024] With this configuration, since no piping for a water channel through which cooling water flows is required around the oil cooler 2, particularly between the inverter 7 and the oil cooler 2, the electric vehicle drive device 1 can be made lighter and smaller. Furthermore, since no water channel through which cooling water flows is provided inside the gear box 6, which is a waterproof compartment of the electric vehicle drive device 1, the intrusion of cooling water into the waterproof compartment can be suppressed. Furthermore, since no piping is provided around the oil cooler 2, there are no protruding piping parts around the oil cooler 2, and therefore no troublesome piping work and no space for handling the piping are required, and an electric vehicle drive device 1 that is easy to install in an electric vehicle can be obtained. Furthermore, since there are no protruding piping parts around the oil cooler 2, the volumetric efficiency of the electric vehicle drive device 1 can be improved.

[0025] In this embodiment, the oil cooler 2 is provided in contact with the motor 3 or the gear box 6 on the side opposite to the inverter 7. At this contact portion, the oil passage 10 and the oil cooler oil passage 2b are connected. The oil cooler 2 is disposed between the inverter 7 and the motor 3 or the gear box 6. In the configuration shown in FIG. 2, the oil cooler 2 is disposed between the inverter 7 and the gear box 6. In the configuration shown in FIG. 1(c), the oil cooler 2 is disposed between the inverter 7 and the motor 3.

[0026] With this configuration, no water passage piping through which cooling water flows is required around the oil cooler 2, particularly between the inverter 7 and the oil cooler 2, and no oil passage piping through which oil flows is required between the motor 3 or gear box 6 and the oil cooler 2, making it possible to reduce the weight and size of the electric vehicle drive device 1. Furthermore, since no piping is provided around the oil cooler 2, there are no protruding piping parts around the oil cooler 2, which means that troublesome piping work and space for handling the piping are not required, making it possible to obtain an electric vehicle drive device 1 that is easy to incorporate into an electric vehicle. Furthermore, since there are no protruding piping parts around the oil cooler 2, the volumetric efficiency of the electric vehicle drive device 1 can be improved.

[0027] An example of the mounting structure of the oil cooler 2 will be described with reference to FIG. 4. Two oil cooler oil passage connecting parts 8 are provided on one side of the oil cooler 2 in the X direction, and two oil cooler water passage connecting parts 9 are provided on the other side of the oil cooler 2 in the X direction. The oil cooler oil passage connecting part 8 is an end part of the oil cooler oil passage 2b. The oil cooler water passage connecting part 9 is an end part of the oil cooler water passage 2a. The oil passage 10 of the gearbox 6 has two oil passage connecting parts 11 on the other side of the X direction. The oil passage connecting part 11 is an end part of the oil passage 10. The first cooling water passage 13a has a cooling water passage connecting part 14a which is an end part of the first cooling water passage 13a on the other side of the X direction, and the second cooling water passage 13b has a cooling water passage connecting part 14b which is an end part of the second cooling water passage 13b on the other side of the X direction.

[0028] Each of the oil cooler oil passage connecting parts 8 is connected to each of the oil passage connecting parts 11. Through these connections, the oil cooler oil passage 2b is connected to the oil passage 10, the gearbox 6 is brought into contact with the oil cooler 2, and the oil cooler 2 is fixed to the gearbox 6. One side of the oil cooler water passage connecting part 9 is connected to the cooling water passage connecting part 14a, and the other side of the oil cooler water passage connecting part 9 is connected to the cooling water passage connecting part 14b. Through these connections, the oil cooler water passage 2a is connected to the first cooling water passage 13a and the second cooling water passage 13b, the inverter 7 is brought into contact with the oil cooler 2, and the oil cooler 2 is fixed to the inverter 7.

[0029] In this embodiment, a nipple 23 is provided as the oil cooler oil passage connection portion 8 and the oil cooler water passage connection portion 9. The oil passage connection portion 11, the cooling water passage connection portion 14a, and the cooling water passage connection portion 14b are provided with recesses that fit with the nipple 23. By connecting these connection portions with a fitting structure, the in-plane deviation of the abutting surfaces is reduced, making it easier to fix both abutting members. The first cooling water passage 13a and the oil cooler water passage 2a, the second cooling water passage 13b and the oil cooler water passage 2a, and the oil passage 10 and the oil cooler oil passage 2b may be connected with a one-touch connector structure. As shown in the fitting structure in the lower right of FIG. 14, in the one-touch connector structure, one of the connected parts is a socket and the other is a plug. The nipple 23 on the plug side is provided with a drip prevention mechanism such as a check valve that simplifies removal. The drip prevention mechanism may be an O-ring. With this configuration, it is possible to prevent oil or cooling water from dripping when removing or replacing the oil cooler 2, and to prevent dirt from getting into the oil cooler water passage 2a or the oil cooler oil passage 2b. Also, it is possible to improve the ease of assembly of the electric vehicle drive device 1.

[0030] The configuration of the inverter 7 will be described in detail. As shown in FIG. 2, the inverter 7 has an electric component 15 and a water-cooled plate 12 in which a first cooling water passage 13a and a second cooling water passage 13b are formed. The electric component 15 is a group of electric and electronic components that convert power and drive and control the motor 3. The electric component 15 is mounted on the water-cooled plate 12. The electric component 15 is surrounded by a cylindrical case 16a. An open portion on the other side of the case 16a in the Z direction abuts against the water-cooled plate 12. An open portion on one side of the case 16a in the Z direction is covered with a cover 16b. The electric component 15 is waterproofed from the outside and insulated and protected from the outside by the case 16a and the cover 16b. The case 16a and the cover 16b are made of a metal such as aluminum.

[0031] The inverter 7 has a cooling water inlet 17 that allows the cooling water to flow into the first cooling water passage 13a, and a cooling water outlet 18 that allows the cooling water to flow out of the second cooling water passage 13b. In this embodiment, as shown in Fig. 1(a), the cooling water inlet 17 and the cooling water outlet 18 are provided on the other side in the X direction of the water-cooled plate 12. The arrangement of the cooling water inlet 17 and the cooling water outlet 18 is not limited thereto, and they may be provided on the other side in the Z direction of the water-cooled plate 12, for example.

[0032] The cooling water inlet 17 and the cooling water outlet 18 are connected to an external water-cooling system. Low-temperature cooling water is supplied from the external water-cooling system to the cooling water inlet 17. The external water-cooling system is composed of, for example, a radiator and a cooling water pump. The cooling water in the external water-cooling system circulates through the first cooling water passage 13a, the oil cooler water passage 2a, and the second cooling water passage 13b by the operation of the cooling water pump. When the cooling water flows through the first cooling water passage 13a and the second cooling water passage 13b, heat generated by the operation of the electric components 15 is absorbed by the cooling water through the solid wall of the water-cooled plate 12. The cooling water, which has been heated by absorbing heat, is discharged from the cooling water outlet 18. The heated cooling water dissipates heat to the surrounding air in the radiator.

[0033] The cooling water inlet 17 and the cooling water outlet 18 are, for example, nipples, and are connected to piping of an external water-cooling system via a sealing structure such as an O-ring or packing. The mounting position and structure of the cooling water inlet 17 and the cooling water outlet 18 are not limited to the above-mentioned configuration, as long as they are connected to the external water-cooling system via piping and have a structure in which cooling water is supplied or discharged. In addition, the cooling water is not limited to a configuration in which it is discharged from the cooling water outlet 18 to the external water-cooling system, and the cooling water may be sent from the cooling water outlet 18 to the motor 3 or other equipment (such as a charger or a booster) to cool the motor 3 or other equipment.

[0034] The details of the connection configuration between the inverter 7 and the oil cooler 2 will be described with reference to Fig. 5(a) to Fig. 5(c). In these figures, the electric components 15 are indicated by dashed lines, the oil cooler water passage 2a by dotted lines, and the oil cooler oil passage 2b by dashed lines. In Fig. 5(a), the oil header 19 and the cooling water header 20 are arranged in the same order so as to be aligned in the Y direction. The oil cooler water passage 2a and the oil cooler oil passage 2b stacked in the X direction are formed to extend in the Z direction when viewed in the X direction. In Fig. 5(b), the oil header 19 and the cooling water header 20 are arranged in the reverse order so that the oil header 19 and the cooling water header 20 are aligned in the Y direction. The oil cooler water passage 2a and the oil cooler oil passage 2b stacked in the X direction are formed to extend obliquely so that their flow paths cross when viewed in the X direction. When the first cooling water passage 13a and the second cooling water passage 13b are arranged side by side on the same plane, in the configuration of the oil cooler 2 shown in Fig. 5(a), both the oil cooler 2 and the inverter 7 can be arranged in the XY plane, but in the configuration of the oil cooler 2 shown in Fig. 5(b), the inverter 7 is arranged at an angle with respect to the XY plane relative to the oil cooler 2. The oil cooler 2 shown in Fig. 5(b) has excellent heat exchange efficiency between the oil and the cooling water, but because the inverter 7 is arranged at an angle, the volumetric efficiency of the oil cooler 2 and the inverter 7 deteriorates.

[0035] Another configuration shown in FIG. 5(c) will be described. In FIG. 5(c), the configuration of the oil cooler 2 is the same as that of the oil cooler 2 shown in FIG. 5(b), and the configuration of the water-cooled plate 12 is different from that of FIG. 5(b). The water-cooled plate 12 has a protrusion 21 protruding in the Z direction from the cooling surface 12a on which the electric components 15 are mounted. The protrusion 21 has a second cooling water passage connecting portion 13b1 connected to the second cooling water passage 13b. The second cooling water passage connecting portion 13b1 and the cooling water header 20 are connected at the oil cooler water passage connecting portion 9. The second cooling water passage 13b, the second cooling water passage connecting portion 13b1, and the cooling water header 20 form an S-shaped flow path when viewed in the Y direction, and both the oil cooler 2 and the inverter 7 can be arranged in the XY plane. By configuring in this manner, even in the oil cooler 2 with the flow path configuration of Figure 5(b) which has good heat exchange efficiency between the oil and the cooling water, both the oil cooler 2 and the inverter 7 can be arranged within the XY plane, thereby realizing an arrangement of the oil cooler 2 and the inverter 7 with good volumetric efficiency.

[0036] <Variation 1> The configuration of the first modified example will be described with reference to Figs. 6 and 7. As shown in Fig. 6, the oil cooler 2 has an end plate 22 on the other side in the X direction where the inverter 7 is provided. The end plate 22 has two oil cooler channel connectors 9 on the other side in the X direction. The oil cooler channel connectors 9 are, for example, nipples 23. The end plate 22 has an end plate channel 22a1 therein that connects the first cooling channel 13a and the second cooling channel 13b to the oil cooler channel 2a. By bending the end plate channel 22a1 in an S-shape in the X direction inside the end plate 22, it is possible to realize an arrangement of the oil cooler 2 and the inverter 7 with good volumetric efficiency, as in Fig. 5(c).

[0037] In the first modification, the motor 3 is provided on the other side of the oil cooler 2 in the X direction. The oil cooler 2 has a first oil cooler oil passage connection portion 8a on one side in the X direction and a second oil cooler oil passage connection portion 8b on the other side in the X direction. In FIG. 6, the second oil cooler oil passage connection portion 8b is not shown because it is on the other side of the oil cooler water passage connection portion 9 in the Z direction. The first oil cooler oil passage connection portion 8a is connected to the oil passage connection portion 11a of the gear box 6, and the second oil cooler oil passage connection portion 8b is connected to the oil passage connection portion 11b of the motor 3. The oil flows in the order of the gear box 6, the oil cooler 2, and the motor 3. As shown in FIG. 7, the electric vehicle drive device 1 may be configured such that the motor 3 is provided on the other side of the oil cooler 2 in the X direction and the oil flows in the order of the gear box 6, the oil cooler 2, and the motor 3.

[0038] <Variation 2> The configuration of the second modification will be described with reference to Figs. 8 and 9. As shown in Fig. 8, the oil cooler 2 has end plates 22 on both one side in the X direction and the other side in the X direction. The end plate 22 provided on the other side in the X direction is called end plate 22a, and the end plate 22 provided on one side in the X direction is called end plate 22b. As a configuration of the water channels inside the end plate 22a, the end plate 22a has two end plate water channels 22a1. The end plate water channel 22a1 on the other side in the Y direction is an end plate water channel 22a1 bent in an S-shape in the X direction. The end plate 22a is connected to the first cooling water channel 13a and the second cooling water channel 13b provided in the water-cooled plate 12 not by nipples but by contact via an O-ring 24 to ensure liquid-tightness.

[0039] The end plate 22b is provided with two oil cooler oil passage connecting portions 8 on one side in the X direction. The oil cooler oil passage connecting portion 8 is a portion that ensures liquid tightness by abutting with the oil passage connecting portion 11 via an O-ring 24. The end plate 22b has two end plate oil passages 22b1 inside that connect the oil passage 10 of the gear box 6 and the oil cooler oil passage 2b. By bending the end plate oil passage 22b1 on one side in the Y direction inside the end plate 22b into an S-shape in the X direction similarly to the end plate water passage 22a1 on the other side in the Y direction of the end plate 22a, the oil passage connecting portions 11 are provided side by side in the Y direction, and therefore an arrangement of the oil cooler 2 and the gear box 6 with good volumetric efficiency can be realized.

[0040] As described above, in the electric vehicle drive device 1 according to the first embodiment, the inverter 7 has the first cooling water passage 13a and the second cooling water passage 13b through which the cooling water flows, the oil cooler 2 has the oil cooler water passage 2a through which the cooling water flows, the oil cooler 2 is provided in contact with the inverter 7, the first cooling water passage 13a and the oil cooler water passage 2a are connected at the contact portion, and the second cooling water passage 13b and the oil cooler water passage 2a are connected, and water passages through which the cooling water flows in the order of the first cooling water passage 13a, the oil cooler water passage 2a, and the second cooling water passage 13b are formed, so that piping of the water passage through which the cooling water flows is not required around the oil cooler 2, particularly in the portion between the inverter 7 and the oil cooler 2, and therefore the electric vehicle drive device 1 can be made lighter and smaller. In addition, since no water passage through which the cooling water flows is provided inside the gear box 6, which is a waterproof compartment of the electric vehicle drive device 1, intrusion of the cooling water into the waterproof compartment can be suppressed. Furthermore, since no piping is provided around the oil cooler 2, there are no protruding piping portions around the oil cooler 2, which eliminates the need for cumbersome piping work and space for handling the piping, making it possible to obtain an electric vehicle drive device 1 that is easy to install into an electric vehicle. Furthermore, since there are no protruding piping portions around the oil cooler 2, the volumetric efficiency of the electric vehicle drive device 1 can be improved.

[0041] When the oil cooler 2 is provided in contact with the motor 3 or the gear box 6 on the opposite side to the inverter 7, the oil passage 10 and the oil cooler oil passage 2b are connected at the contact portion, and the oil cooler 2 is sandwiched between the inverter 7 and the motor 3 or the gear box 6, no piping is required for a water passage through which cooling water flows around the oil cooler 2, particularly between the inverter 7 and the oil cooler 2, and no piping is required for an oil passage through which oil flows between the motor 3 or the gear box 6 and the oil cooler 2, so that the electric vehicle drive device 1 can be made lighter and smaller. In addition, since no piping is provided around the oil cooler 2, there is no protruding part of the piping around the oil cooler 2, so troublesome piping work and space for handling the piping are not required, and an electric vehicle drive device 1 that is easy to install in an electric vehicle can be obtained. In addition, since there is no protruding part of the piping around the oil cooler 2, the volume efficiency of the electric vehicle drive device 1 can be improved. Furthermore, when the first cooling water passage 13a and the oil cooler water passage 2a, the second cooling water passage 13b and the oil cooler water passage 2a, and the oil passage 10 and the oil cooler oil passage 2b are connected by a one-touch connector structure, it is possible to prevent oil or cooling water from dripping when removing or replacing the oil cooler 2, and to prevent dirt from getting into the oil cooler water passage 2a or the oil cooler oil passage 2b. Also, it is possible to improve the ease of assembly of the electric vehicle drive device 1.

[0042] Embodiment 2 An electric vehicle drive device 1 according to the second embodiment will be described. Fig. 10 is a side view showing the oil cooler 2 and inverter 7 which are main parts of the electric vehicle drive device 1 according to the second embodiment, showing one side in the X direction, and Fig. 11 is a plan view showing the oil cooler 2 and inverter 7 which are main parts of the electric vehicle drive device 1, showing the oil cooler 2 and inverter 7 with the cover 16b removed. The electric vehicle drive device 1 according to the second embodiment has a configuration in which the oil cooler 2 is provided on the cooling surface 12a of the water-cooled plate 12.

[0043] 11, the inverter 7 has an electric component 15 and a water-cooled plate 12 having a first cooling water passage 13a and a second cooling water passage 13b formed therein. The water-cooled plate 12 has a cooling surface 12a on which the electric component 15 is mounted. The oil cooler 2 is provided in contact with the cooling surface 12a and is arranged next to the electric component 15.

[0044] The electric components 15 are covered with the case 16a and the cover 16b. In this embodiment, the oil cooler 2 is provided on one side of the case 16a in the X direction. The arrangement of the oil cooler 2 is not limited thereto, and the oil cooler 2 may be provided on one side of the case 16a in the Y direction, for example. The oil cooler 2 is fixed to the cooling surface 12a by soldering or brazing, for example. The oil cooler 2 may be fixed to the cooling surface 12a by bolts. When the oil cooler 2 has the oil cooler oil passage connection part 8 or the oil cooler water passage connection part 9 on the cooling surface 12a side, a seal structure using an O-ring or a packing is provided at the connection part with the oil passage or the cooling water passage so that oil or cooling water does not leak between the oil cooler 2 and the cooling surface 12a.

[0045] By providing the oil cooler 2 in contact with the cooling surface 12a and arranging the oil cooler 2 and the electric component 15 side by side in this manner, piping between the inverter 7 and the oil cooler 2 is not necessary and the connection between the inverter 7 and the oil cooler 2 can be simplified, thereby making it possible to reduce the size and weight of the electric vehicle drive device 1. Furthermore, since the inverter 7 and the oil cooler 2 of the electric vehicle drive device 1 are integrated into one structure, it is possible to improve the ease of mounting the electric vehicle drive device 1 to the electric vehicle. Furthermore, since the inverter 7 and the oil cooler 2 are integrated into one structure, it is possible to improve the strength and vibration resistance of the inverter 7 and the oil cooler 2.

[0046] In this embodiment, the inverter 7 has a power module 25 and a condenser 26 arranged adjacent to the first cooling water passage 13a, and a cooling water inlet 17 that allows the cooling water to flow into the first cooling water passage 13a. The inverter 7 further has a cooling water outlet 18 that allows the cooling water to be sent out from the second cooling water passage 13b. In this embodiment, the cooling water inlet 17 and the cooling water outlet 18 are provided on the other side of the water-cooled plate 12 in the X direction. The cooling water inlet 17 and the cooling water outlet 18 are, for example, nipples. The power module 25 and the condenser 26 are electric components 15 mounted on the cooling surface 12a. The electric components 15 mounted on the cooling surface 12a are not limited to the power module 25 and the condenser 26, and other electric components such as a transformer may be mounted on the cooling surface 12a.

[0047] The flow path of the cooling water through which the cooling water circulates will be described. In FIG. 11, the direction of the cooling water flow is indicated by solid arrows. The cooling water passage connecting portion 14a of the first cooling water passage 13a and the oil cooler water passage connecting portion 9 are connected to the cooling surface 12a, and the cooling water passage connecting portion 14b of the second cooling water passage 13b and the oil cooler water passage connecting portion 9 are connected to the cooling surface 12a. Low-temperature cooling water is supplied to the cooling water inlet portion 17 from an external water-cooling system. The cooling water circulates through the first cooling water passage 13a, the oil cooler water passage 2a, and the second cooling water passage 13b in this order by the operation of a cooling water pump (not shown). Since the low-temperature cooling water flows first through the first cooling water passage 13a, it is preferable to form the first cooling water passage 13a in accordance with the arrangement of the electric components 15 that are likely to generate heat, so that the cooling can be performed more efficiently.

[0048] In this embodiment, the first cooling water passage 13a is provided so that the cooling water flowing in from the cooling water inlet portion 17 passes through the portion of the first cooling water passage 13a where the power module 25 and the condenser 26 are arranged adjacent to each other, in the order of the power module 25 and the condenser 26. Of the electric components 15, the power module 25 is the component that is most likely to generate heat. The condenser 26 is an electric component 15 that generates heat and has a low allowable temperature. With this configuration, the low-temperature cooling water flows through the power module 25 and the condenser 26 in that order, so that the power module 25 and the condenser 26 can be cooled more efficiently.

[0049] After cooling the power module 25 and the condenser 26, the cooling water exchanges heat with the oil and then flows through the second cooling water passage 13b. Since heated cooling water flows through the second cooling water passage 13b, it is preferable to place electrical components with a high allowable temperature and electrical components with a small amount of heat generation therein.

[0050] In this embodiment, a part of the oil passage 10 is provided inside the water-cooled plate 12. In Fig. 10 and Fig. 11, the direction of oil flow is indicated by a dashed arrow. The oil cooler oil passage connection part 8 on the upstream side where the oil flows in is connected to the first plate oil passage connection part 27a provided on the cooling surface 12a of the water-cooled plate 12 against which the oil cooler 2 abuts. The second plate oil passage connection part 28a provided on the side of the water-cooled plate 12 against which the gear box 6 abuts is connected to the oil passage connection part 11 of the gear box 6. The plate oil passage 10a is formed in the part of the water-cooled plate 12 between the first plate oil passage connection part 27a and the second plate oil passage connection part 28a. The plate oil passage 10a is an oil passage formed in an L-shape when viewed in the Y direction. The oil cooler oil passage connection part 8 and the oil passage connection part 11 are connected via the plate oil passage 10a, allowing oil to pass through.

[0051] The downstream oil cooler oil passage connection 8 from which the oil is discharged is connected to a first plate oil passage connection 27b provided on the cooling surface 12a of the water-cooled plate 12 with which the oil cooler 2 abuts. An opening 29 is provided in a second plate oil passage connection 28b provided on the other surface in the Z direction of the water-cooled plate 12 from which the oil is discharged to the outside. A plate oil passage 10b is formed in a portion of the water-cooled plate 12 between the first plate oil passage connection 27b and the second plate oil passage connection 28b. In this embodiment, a nipple 23 is provided in the opening 29, and the nipple 23 is connected to an oil passage connection provided in the motor 3.

[0052] In this embodiment, the oil cooler oil passage connection part 8 is connected to an external oil passage connection part via the plate oil passages 10a and 10b, but the present invention is not limited to this. The oil cooler oil passage connection part 8 may be exposed and directly connected to an external oil passage connection part without providing the plate oil passages 10a and 10b.

[0053] As described above, in the electric vehicle drive device 1 according to the second embodiment, the inverter 7 has the electric component 15 and the water-cooled plate on which the first cooling water passage 13a and the second cooling water passage 13b are formed, the water-cooled plate 12 has the cooling surface 12a on which the electric component 15 is mounted, and the oil cooler 2 is provided in contact with the cooling surface 12a and arranged side by side with the electric component 15. This eliminates the need for piping between the inverter 7 and the oil cooler 2, and simplifies the connection between the inverter 7 and the oil cooler 2, thereby making it possible to reduce the size and weight of the electric vehicle drive device 1. In addition, since the inverter 7 and the oil cooler 2 of the electric vehicle drive device 1 are integrated into a structure, it is possible to improve the workability of mounting the electric vehicle drive device 1 to the electric vehicle. In addition, since the inverter 7 and the oil cooler 2 are integrated into a structure, it is possible to improve the strength and vibration resistance of the inverter 7 and the oil cooler 2.

[0054] When the inverter 7 has a power module 25 and a condenser 26 arranged adjacent to the first cooling water passage 13a, and a cooling water inlet portion 17 that allows cooling water to flow into the first cooling water passage 13a, and the first cooling water passage 13a is arranged so that the cooling water flowing in from the cooling water inlet portion 17 passes through the portion of the first cooling water passage 13a where the power module 25 and the condenser 26 are arranged adjacent to each other, in that order, the power module 25 is the component among the electrical components 15 that is most likely to generate heat, and the condenser 26 is also an electrical component 15 that is likely to generate heat, so that low-temperature cooling water flows through the power module 25 and the condenser 26 in that order, and therefore the power module 25 and the condenser 26 can be cooled more efficiently.

[0055] Embodiment 3 An electric vehicle drive device 1 according to the third embodiment will be described. Fig. 12 is a side view showing the oil cooler 2 and inverter 7 which are main parts of the electric vehicle drive device 1 according to the third embodiment, showing one side in the X direction, and Fig. 13 is a plan view showing the oil cooler 2 and inverter 7 which are main parts of the electric vehicle drive device 1, with the cover 16b removed. The electric vehicle drive device 1 according to the third embodiment has a configuration in which a cooling water pump 30 is provided on the cooling surface 12a of the water-cooled plate 12.

[0056] The inverter 7 has a water-cooled plate 12 having a first cooling water passage 13a and a second cooling water passage 13b formed therein, and a cooling water pump 30 that circulates cooling water through the passages. The cooling water pump 30 is provided in contact with the water-cooled plate 12. In this embodiment, the cooling water pump 30 is provided in contact with the cooling surface 12a of the water-cooled plate 12, and is provided on one side in the X direction of the case 16a and the cover 16b that cover the electric components 15. The cooling water pump 30 is connected to the cooling water passage connecting portion 14a side of the first cooling water passage 13a. The inverter 7 supplies power to the cooling water pump 30 and controls the drive of the cooling water pump 30.

[0057] By configuring it in this manner, the cooling water pump 30 and the inverter 7 are integrated into one structure, so that the wiring connecting the cooling water pump 30 and the inverter 7 can be shortened and the wiring connections can be simplified, thereby making the electric vehicle drive device 1 lighter and more compact.

[0058] In this embodiment, the oil cooler 2 is provided in contact with the cooling surface 12a, and the oil cooler 2 and the electrical components 15 are arranged side by side. By forming an integrated structure (3-in-1) consisting of the inverter 7, the oil cooler 2, and the cooling water pump 30, the workability of mounting the electric vehicle drive device 1 to the electric vehicle can be improved. Also, since the inverter 7, the oil cooler 2, and the cooling water pump 30 are integrated, the strength and vibration resistance of the inverter 7, the oil cooler 2, and the cooling water pump 30 can be improved.

[0059] Embodiment 4 An electric vehicle drive device 1 according to a fourth embodiment will be described. Fig. 14(a) is a cross-sectional view showing an oil cooler 2 which is a main part of the electric vehicle drive device 1 according to the fourth embodiment, and is a cross-sectional view taken at the AA cross-section position of Fig. 14(b), Fig. 14(b) is a cross-sectional view of the oil cooler 2 which is a main part of another electric vehicle drive device 1 according to the fourth embodiment, and is a cross-sectional view taken at the CC cross-section position of Fig. 15(b), Fig. 15(b) is a cross-sectional view of the oil cooler 2 which is a main part of another electric vehicle drive device 1 according to the fourth embodiment, and is a cross-sectional view taken at the DD cross-section position of Fig. 15(a), Fig. 16(a) is a cross-sectional view showing an oil cooler 2 which is a main part of another electric vehicle drive device 1 according to the fourth embodiment, and is a cross-sectional view taken at the EE cross-section position of Fig. 16(b), and Fig. 16(b) is a cross-sectional view of the oil cooler 2 which is a main part of the electric vehicle drive device 1 according to the fourth embodiment, and is a cross-sectional view taken at the FF cross-section position of Fig. 16(a). The electric vehicle driving device 1 according to the fourth embodiment is configured such that the oil cooler 2 is provided with a power conversion mechanism 31 that generates an oil flow by a water flow.

[0060] The oil cooler 2 has an oil cooler water passage 2a through which cooling water flows and an oil cooler oil passage 2b through which oil flows, and the oil cooler water passage 2a and the oil cooler oil passage 2b are arranged separately and do not communicate with each other. The oil cooler 2 is provided with a power conversion mechanism 31 that uses the water flow of the cooling water flowing in the oil cooler water passage 2a as power to generate an oil flow in the oil cooler oil passage 2b.

[0061] The configuration of the power conversion mechanism 31 of this embodiment will be described with reference to Figures 14(a) and 14(b). The oil cooler 2 has an end plate 22 which is a part of the oil cooler 2. A part of the oil cooler 2 different from the end plate 22 is a main body 2c of the oil cooler 2. The end plate 22 has an oil cooler water passage 2a and an oil cooler oil passage 2b which are arranged separately and without communicating with each other, and the power conversion mechanism 31 is provided on the end plate 22.

[0062] The power conversion mechanism 31 accommodates gears 32 made of a pair of magnets, or gears 32 with one magnet and the other made of a magnetic material, in each of the isolated oil cooler water passage 2a and oil cooler oil passage 2b. Rotation of the gear 32 on the oil cooler water passage 2a side is transmitted to the gear 32 on the oil cooler oil passage 2b side by magnetic force. The gear 32 on the oil cooler water passage 2a side is referred to as gear 32a, and the gear 32 on the oil cooler oil passage 2b side is referred to as gear 32b. The gear 32b rotates as the rotation of the gear 32a is transmitted to the gear 32b. Note that the gear 32 is only required to transmit a rotational force from the gear 32a to the gear 32b, and therefore all or a part of the gear 32 may be made of a magnet or a magnetic material.

[0063] In Fig. 14(a) and Fig. 14(b), the direction of flow of the cooling water is indicated by a thick arrow, and the direction of flow of the oil is indicated by a thin arrow. The arrows drawn by thick and thin have different shapes of the tips of the arrows. The flow path of the cooling water will be described. The cooling water is supplied to the first cooling water passage 13a from an external water cooling system, and the cooling water that passes through the first cooling water passage 13a flows from the oil cooler water passage connection part 9 into the oil cooler water passage 2a1 in the end plate 22 shown on the left side of Fig. 14(a). After passing through the oil cooler water passage 2a of the main body part 2c of the oil cooler 2, the cooling water flows into the oil cooler water passage 2a2 in the end plate 22, passes through the oil cooler water passage 2a2 shown by a broken line on the right side of Fig. 14(a), and flows into the second cooling water passage 13b from the oil cooler water passage connection part 9. 14(b), the gear 32a is provided on the end plate 22 so that a portion of the gear 32a is exposed to the oil cooler water passage 2a2. The gear 32a rotates when the cooling water flows through the oil cooler water passage 2a2.

[0064] The oil flow path will be described. The oil flows from the first oil cooler oil passage connection part 8a shown in the lower right of Fig. 14(b) into the oil cooler oil passage 2b in the main body part 2c of the oil cooler 2. After passing through the oil cooler oil passage 2b in the main body part 2c, the oil flows into the oil cooler oil passage 2b in the end plate 22 and is discharged from the second oil cooler oil passage connection part 8b. The gear 32b is provided on the end plate 22 so that a part of it is exposed to the oil cooler oil passage 2b, as shown in Fig. 14(a).

[0065] With this configuration, the gear 32b rotates due to the rotation of the gear 32a, so that the oil in the oil cooler oil passage 2b can be sucked from the side of the main body 2c of the oil cooler 2, and the oil can be discharged from the second oil cooler oil passage connection part 8b. This flow of oil causes low-temperature oil that has been heat-exchanged between the cooling water and the oil to be discharged from the second oil cooler oil passage connection part 8b, so that low-temperature oil can be supplied to the heat-generating part of the electric vehicle drive device 1. In the heat-generating part to which the low-temperature oil is supplied, the heat-generating part can be cooled directly or indirectly by the heat absorption of the oil. In addition, the flow of cooling water supplied from the external water-cooling system can circulate the oil that cools the heat-generating part of the electric vehicle drive device 1, so that an oil pump for circulating the oil is not required, and therefore the electric vehicle drive device 1 can be made lighter and smaller. In addition, the oil flow is generated by the water flow, so that power consumption can be reduced.

[0066] The end plate 22 housing the gear 32 may be provided on any surface of the oil cooler 2. The rotating body provided in the power conversion mechanism 31 is not limited to a gear. For example, a configuration in which multiple impellers are provided on a rotating shaft may be used. By using the gear 32 as the rotating body provided in the power conversion mechanism 31, the power conversion mechanism 31 can be made smaller and less expensive.

[0067] The end plates 22 are desirably made of a material that easily transmits magnetic force, and are made of, for example, a resin material. The magnet or magnetic material that constitutes the gear 32 is desirably not rusted even in the oil cooler water passage 2a2. Examples of magnets or magnetic materials that do not rust include ferrite, alnico, iron chrome cobalt, samarium cobalt, and samarium iron nitrogen. In addition, when using a rustable material such as iron as the magnetic material, it is desirably coated with paint (organic coating) or plating (inorganic coating).

[0068] In addition, since the power conversion mechanism 31 in the present disclosure uses magnetic force, unlike a power conversion mechanism in which gears are connected by a shaft, the oil cooler water passage 2a and the oil cooler oil passage 2b are arranged separately and not in communication with each other, so there is no risk of cooling water leaking from the oil cooler water passage 2a to the oil cooler oil passage 2b along the periphery of the shaft connecting the gears. Since cooling water does not leak from the oil cooler water passage 2a to the oil cooler oil passage 2b, it is possible to prevent a failure of the electric vehicle drive device 1 caused by the intrusion of cooling water into the oil cooler oil passage 2b. In addition, by integrating the inverter, the oil cooler 2 having the function of an oil pump, and the cooling water pump into a single structure, it is possible to easily install them into the electric vehicle drive device 1.

[0069] <Variation 1> The configuration of the first modified example will be described with reference to Figs. 15(a) and 15(b). The configuration shown in Fig. 15(b) differs from the configuration shown in Fig. 14(b) in the direction in which the gear 32 is provided. In the configuration shown in Fig. 14(b), the gear 32 is provided parallel to the side surface 2c1 of the main body 2c of the oil cooler 2. In the configuration shown in Fig. 15(b), the gear 32 is provided perpendicular to the side surface 2c1 of the main body 2c of the oil cooler 2. In addition, the configurations shown in Figs. 14 and 15 differ in the direction in which the oil is discharged from the second oil cooler oil passage connection portion 8b. In the configuration shown in Fig. 14(b), the oil is discharged in a direction perpendicular to the side surface 2c1 of the main body 2c of the oil cooler 2. In the configuration shown in Fig. 15(b), the oil is discharged in a direction parallel to the side surface 2c1 of the main body 2c of the oil cooler 2. The configuration shown in Fig. 14(b) allows the end plate 22 to be made smaller than the configuration shown in Fig. 15(b).

[0070] <Variation 2> The configuration of the modified example 2 will be described with reference to Figs. 16(a) and 16(b). The configuration shown in Fig. 16(a) differs from the configuration shown in Fig. 14(a) in the position where the first oil cooler oil passage connection part 8a is provided. In the configuration shown in Fig. 14(a), the first oil cooler oil passage connection part 8a is provided in the main body part 2c of the oil cooler 2. In the configuration shown in Fig. 16(a), the first oil cooler oil passage connection part 8a is provided in the end plate 22. With this configuration, both the first oil cooler oil passage connection part 8a and the second oil cooler oil passage connection part 8b can be arranged on the same side of the end plate 22. Since both the first oil cooler oil passage connection part 8a and the second oil cooler oil passage connection part 8b are arranged on the same side of the end plate 22, the productivity of the electric vehicle drive device 1 can be improved.

[0071] Additionally, while the present disclosure describes various exemplary embodiments and examples, the various features, aspects, and functions described in one or more embodiments are not limited to application to a particular embodiment, but may be applied to the embodiments alone or in various combinations. Therefore, countless modifications not exemplified are assumed within the scope of the technology disclosed in the present specification, including, for example, modifying, adding, or omitting at least one component, and further, extracting at least one component and combining it with a component of another embodiment.

[0072] Various aspects of the present disclosure are summarized below as appendices. (Appendix 1) A motor; a gear box that accommodates a reduction mechanism connected to the motor and a differential mechanism connected to the reduction mechanism; an inverter electrically connected to the motor and configured to convert electric power; an oil cooler that cools the motor, the inverter has a first cooling water passage and a second cooling water passage through which cooling water flows, The oil cooler has an oil cooler water passage through which cooling water flows, The oil cooler is provided in contact with the inverter, At the abutment portion, the first cooling water passage and the oil cooler water passage are connected to each other, and the second cooling water passage and the oil cooler water passage are connected to each other, An electric vehicle drive device in which a water passage is formed through which cooling water flows in the following order: the first cooling water passage, the oil cooler water passage, and the second cooling water passage. (Appendix 2) The oil cooler has an oil cooler oil passage through which oil flows, The motor and the gear box have oil passages connected to the oil cooler oil passage, The oil cooler is provided in contact with the motor or the gear box on the opposite side to the inverter, The oil passage and the oil cooler oil passage are connected at the abutment portion, 2. The electric vehicle drive device according to claim 1, wherein the oil cooler is disposed between the inverter and the motor or the gear box. (Appendix 3) the inverter includes an electric component and a water-cooled plate having the first cooling water passage and the second cooling water passage formed therein; the water-cooled plate has a cooling surface on which the electrical components are mounted; 2. The electric vehicle drive device according to claim 1, wherein the oil cooler is provided in contact with the cooling surface and is arranged alongside the electrical component. (Appendix 4) the inverter includes a power module and a capacitor disposed adjacent to the first cooling water passage, and a cooling water inlet portion that allows cooling water to flow into the first cooling water passage; 4. The electric vehicle drive device according to any one of claims 1 to 3, wherein the first cooling water channel is configured so that the cooling water flowing in from the cooling water inlet portion passes through a portion of the first cooling water channel in which the power module and the capacitor are arranged adjacent to each other, in that order, through the power module and the capacitor. (Appendix 5) the inverter includes a water-cooled plate having the first cooling water passage and the second cooling water passage formed therein, and a cooling water pump that circulates cooling water through the water passages, 5. The electric vehicle driving device according to claim 1, wherein the cooling water pump is provided in contact with the water-cooled plate. (Appendix 6) The oil cooler has an oil cooler oil passage through which oil flows, The oil cooler water passage and the oil cooler oil passage are arranged separately and without communicating with each other, 6. The electric vehicle drive device according to any one of claims 1 to 5, further comprising a power conversion mechanism that uses a water flow of cooling water flowing in the oil cooler water passage as power to generate an oil flow in the oil cooler oil passage. (Appendix 7) the power conversion mechanism accommodates gears each having a pair of magnets, or one of which is a magnet and the other of which is made of a magnetic material, in each of the oil cooler water passage and the oil cooler oil passage, which are isolated from each other; 7. The electric vehicle drive device according to claim 6, wherein rotation of a gear on a side of the oil cooler water passage is transmitted to a gear on a side of the oil cooler oil passage by a magnetic force. (Appendix 8) 3. The electric vehicle drive device according to claim 2, wherein the first cooling water passage and the oil cooler water passage, the second cooling water passage and the oil cooler water passage, and the oil passage and the oil cooler oil passage are connected by a one-touch connector structure. [Explanation of symbols]

[0073] 1 Electric vehicle drive device, 2 Oil cooler, 2a, 2a1, 2a2 Oil cooler water passage, 2b Oil cooler oil passage, 2c Main body, 2c1 Side, 3 Motor, 3a Rotating shaft, 3b Rotor, 3c Housing, 3d Stator, 4 Reduction mechanism, 5 Differential mechanism, 6 Gear box, 6a Drive shaft, 7 Inverter, 8 Oil cooler oil passage connection portion, 8a First oil cooler oil passage connection portion, 8b Second oil cooler oil passage connection portion, 9 Oil cooler water passage connection portion, 10 Oil passage, 10a, 10b Plate oil passage, 11, 11a, 11b Oil passage connection portion, 12 Water-cooled plate, 12a Cooling surface, 13a First cooling water passage, 13b Second cooling water passage, 13b1 Second cooling water passage connection portion, 14a, 14b Cooling water passage connection portion, 15 Electrical parts, 16a case, 16b cover, 17 cooling water inlet, 18 cooling water outlet, 19 oil header, 20 cooling water header, 21 protrusion, 22, 22a, 22b end plate, 22a1 end plate water passage, 22b1 end plate oil passage, 23 nipple, 24 O-ring, 25 power module, 26 capacitor, 27a, 27b first plate oil passage connection, 28a, 28b second plate oil passage connection, 29 opening, 30 cooling water pump, 31 power conversion mechanism, 32, 32a, 32b gears

Claims

1. A motor; a gear box that houses a reduction mechanism connected to the motor and a differential mechanism connected to the reduction mechanism; an inverter electrically connected to the motor and configured to convert electric power; an oil cooler that cools the motor, the inverter has a first cooling water passage and a second cooling water passage through which cooling water flows, The oil cooler has an oil cooler water passage through which cooling water flows, The oil cooler is provided in contact with the inverter, At the abutment portion, the first cooling water passage and the oil cooler water passage are connected to each other, and the second cooling water passage and the oil cooler water passage are connected to each other, An electric vehicle drive device in which a water passage is formed through which cooling water flows in the following order: the first cooling water passage, the oil cooler water passage, and the second cooling water passage.

2. The oil cooler has an oil cooler oil passage through which oil flows, The motor and the gear box have oil passages connected to the oil cooler oil passage, The oil cooler is provided in contact with the motor or the gear box on the opposite side to the inverter, The oil passage and the oil cooler oil passage are connected at the abutment portion, The electric vehicle drive device according to claim 1 , wherein the oil cooler is disposed between the inverter and the motor or the gear box.

3. the inverter includes an electric component and a water-cooled plate having the first cooling water passage and the second cooling water passage formed therein; the water-cooled plate has a cooling surface on which the electrical components are mounted; The electric vehicle drive device according to claim 1 , wherein the oil cooler is provided in contact with the cooling surface and is arranged next to the electrical component.

4. the inverter includes a power module and a capacitor disposed adjacent to the first cooling water passage, and a cooling water inlet portion that allows cooling water to flow into the first cooling water passage; 2. The electric vehicle drive device according to claim 1, wherein the first cooling water channel is configured so that the cooling water flowing in from the cooling water inlet portion passes through the power module and the capacitor in that order, through a portion of the first cooling water channel in which the power module and the capacitor are arranged adjacent to each other.

5. the inverter includes a water-cooled plate having the first cooling water passage and the second cooling water passage formed therein, and a cooling water pump that circulates cooling water through the water passages, The electric vehicle drive device according to claim 1 , wherein the cooling water pump is provided in contact with the water-cooled plate.

6. The oil cooler has an oil cooler oil passage through which oil flows, The oil cooler water passage and the oil cooler oil passage are arranged separately and without communicating with each other, 2. The electric vehicle drive device according to claim 1, further comprising a power conversion mechanism that generates an oil flow in the oil cooler oil passage by using a water flow of cooling water flowing in the oil cooler water passage as power.

7. the power conversion mechanism accommodates gears each made of a pair of magnets, or one of which is a magnet and the other made of a magnetic material, in each of the oil cooler water passage and the oil cooler oil passage, which are isolated from each other; The electric vehicle drive device according to claim 6, wherein rotation of the gear on the side of the oil cooler water passage is transmitted to the gear on the side of the oil cooler oil passage by magnetic force.

8. The electric vehicle drive device according to claim 2 , wherein the first cooling water passage and the oil cooler water passage, the second cooling water passage and the oil cooler water passage, and the oil passage and the oil cooler oil passage are connected by a one-touch connector structure.

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