Vehicle drive device

Abstract

To provide a vehicle drive device which enables efficient heat management while being reduced in size.SOLUTION: A vehicle drive device includes: an integrated unit 1 in which an electric-vehicular drive unit 2 including at least an electric motor 21 for transmitting driving rotational force to a travel system of a vehicle and an electronic circuit unit 3 including at least an electronic circuit 31 for driving the electric motor 21 are incorporated in a housing 5 to be integrated; a cooling plate 36 to which the electronic circuit unit 3 is fixed, and through an inside of which cooling liquid flows; and a water pump 51 for circulating the cooling liquid to inside the cooling plate 36. The water pump 51 is fixed to an outer surface 5A of the housing 5 at such a position as to overlap at least a part of the cooling plate 36 in a side view.SELECTED DRAWING: Figure 4

Description

[Technical field]

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

[0002] Conventionally, there is known an electric vehicle drive unit that includes at least an electric motor that transmits drive torque to the vehicle's running system (see, for example, Patent Document 1). This electric vehicle drive unit is made compact by integrating the electric motor and gear unit into a housing, and is connected to a cooling system that exchanges heat between oil circulating in the electric vehicle drive unit and coolant.

[0003] The cooling system described in Patent Document 1 has an inverter unit attached to an electric vehicle drive unit, and uses a water pump to exchange heat between cooling water circulating from the inverter unit to an oil cooler and oil circulating through the electric vehicle drive unit. Here, the water pump is attached to the lower part of the motor housing part of the electric vehicle drive unit, and a cooling pipe is laid between the water pump and the inverter unit. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-178485 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the cooling system described in Patent Document 1, the water pump is attached to the lower part of the housing and the cooling piping is exposed, so heat is dissipated through the cooling piping, reducing the heat recovery rate.

[0006] Therefore, there is a demand for a vehicle drive device that is compact yet capable of efficient heat management. [Means for solving the problem]

[0007] The characteristic configuration of the vehicle drive device of the present invention is that it comprises an integrated unit in which an electric vehicle drive unit including at least an electric motor that transmits drive rotational force to the vehicle's running system, and an electronic circuit unit including at least an electronic circuit for driving the electric motor are built into a housing and integrated into the housing, a cooling plate to which the electronic circuit unit is fixed and through which coolant flows, and a water pump that circulates the coolant inside the cooling plate, and the water pump is fixed to the outer surface of the housing at a position overlapping at least a portion of the cooling plate in a side view.

[0008] This characteristic configuration includes an integrated unit that integrates an electric vehicle drive unit and an electronic circuit unit, making it possible to achieve a smaller size than if the electric vehicle drive unit and the electronic circuit unit were arranged separately.

[0009] In this characteristic configuration, the water pump is fixed to the outer surface of the housing at a position overlapping at least a portion of the cooling plate in a side view. This allows the coolant to circulate between the cooling plate and the water pump inside the integrated unit. It also makes it possible to shorten the length of the piping connecting the cooling plate and the water pump, suppressing heat dissipation through the piping and improving the heat recovery rate.

[0010] In this way, a vehicle drive device that is compact yet capable of efficient heat management is achieved. [Brief description of the drawings]

[0011] [Figure 1] FIG. [Diagram 2] FIG. 2 is a partial vertical cross-sectional view of the integrated unit. [Diagram 3] 1 is a schematic diagram showing a vehicle drive device according to a first embodiment. [Figure 4] 1 is a schematic diagram showing a vehicle drive device according to a first embodiment. [Diagram 5] 1 is a diagram showing a circuit configuration of a vehicle drive device according to a first embodiment. [Figure 6] FIG. 13 is a side view of a water-cooled plate housed in an integrated unit. [Figure 7] FIG. 2 is a perspective view of a water-cooled plate on which an oil cooler is mounted. [Figure 8] 1 is a partial perspective cross-sectional view of a vehicle drive device according to a first embodiment. [Figure 9] 1 is a partial side view of a vehicle drive device according to a first embodiment. [Figure 10] 1 is a partial side view of a vehicle drive device according to a first embodiment. [Figure 11] FIG. 11 is a schematic diagram showing a vehicle drive device according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment of a vehicle drive device will be described with reference to the drawings. However, the present invention is not limited to the following embodiment, and various modifications are possible without departing from the spirit and scope of the present invention.

[0013] An electric vehicle is configured with an electric vehicle drive unit that drives wheels with current supplied from a battery. Examples of electric vehicles include automobiles equipped with a motor as a driving source for traveling (such as hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), battery electric vehicles (BEVs), and fuel cell electric vehicles (FCEVs)).

[0014] [First embodiment] The electric vehicle includes an integrated unit 1 shown in FIG. 1 and FIG. 2. The integrated unit 1 includes an electric vehicle drive unit 2 (hereinafter referred to as a "vehicle drive unit 2"), an electronic circuit unit 3, and a cooling module 4 (an example of a refrigerant unit). In the integrated unit 1, the vehicle drive unit 2 and the electronic circuit unit 3 are housed and integrated in a unit case 5 (an example of a housing). The cooling module 4 is disposed adjacent to the electronic circuit unit 3. In the following figures, as shown in FIG. 1, for example, the traveling direction of the vehicle (front-rear direction of the vehicle) is the X direction, the width direction of the vehicle (left-right direction of the vehicle) is the Y direction, and the height direction of the vehicle is the Z direction. In addition, the front side of the traveling direction of the vehicle is the X1 side, the rear side of the traveling direction is the X2 side, the left side in the vehicle width direction is the Y1 side, and the right side in the vehicle width direction is the Y2 side.

[0015] In the cooling module 4, a chiller 86, a water-cooled condenser 81, an accumulator 82, and auxiliary devices such as valves and pumps, which will be described later, as well as a part of a cooling flow path B and a refrigerant flow path D, are modularized and assembled into a unit case 5. In Fig. 2, only a refrigerant manifold 4a including a refrigerant flow path D is shown among the cooling module 4. A vehicle drive device A in the present embodiment described below shows an example in which a vehicle drive unit 2, an electronic circuit unit 3, and a refrigerant manifold 4a are housed in a unit case 5, but the shape and structure of the integrated unit 1 are not particularly limited.

[0016] The vehicle drive unit 2 includes at least an electric motor 21 that transmits drive torque to the vehicle's running system. Specifically, the vehicle drive unit 2 includes the electric motor 21, a gear 22 having a reduction mechanism, and the like. The electronic circuit unit 3 includes at least an electronic circuit 31 for driving the electric motor 21 and the like. The electronic circuit unit 3 is housed in a unit case 5 to configure a power source module 100.

[0017] As shown in Fig. 2, the integrated unit 1 has a unit case 5 in which the vehicle drive unit 2 is disposed below and the electronic circuit unit 3 is disposed above. As shown in Fig. 3 and Fig. 4, the integrated unit 1 has a first space 11 in which the vehicle drive unit 2 is disposed, a second space 12 in which the electronic circuit unit 3 is disposed, and a partition wall S that partitions the first space 11 and the second space 12. That is, the integrated unit 1 is partitioned by the partition wall S into the first space 11 at the bottom and the second space 12 at the top.

[0018] The electronic circuit unit 3 is disposed on the upper part of the unit case 5 and fixed to the partition wall S. The vehicle drive unit 2 is disposed below the partition wall S. As shown in FIG. 3, the cooling module 4 is disposed adjacent to the electronic circuit unit 3. Specifically, a refrigerant manifold 4a is disposed on the upper part of the unit case 5, and a water-cooled condenser 81 is attached to a side surface 5A (an example of an outer surface) of the unit case 5. In this manner, the integrated unit 1 has a cooling module 4 in which the refrigerant manifold 4a including the refrigerant flow path D through which the refrigerant flows and the water-cooled condenser 81 are integrated. In the cooling module 4, the refrigerant manifold 4a is located above the water-cooled condenser 81.

[0019] 4, the valve unit 6 is disposed on a side surface 5A of the unit case 5. In this embodiment, on the side surface 5A of the unit case 5, the water-cooled condenser 81 is located on the left side (Y1 direction side) of the front side (X1 direction side), and the valve unit 6 is located on the right side (Y2 direction side) of the front side (X1 direction side). The valve unit 6 is disposed in the cooling flow path B, and includes a water pump 51 and a valve 52.

[0020] 2 to 4, a plurality of electronic components constituting an on-board charger (OBC) 32 (voltage conversion circuit) and an inverter (INV) 33 as an electronic circuit 31 are mounted on a substrate 35. The inverter 33 controls the current supplied from the battery 87 to the electric motor 21. The on-board charger 32 controls at least the voltage to be charged to the battery 87. In this embodiment, the inverter 33 is disposed on the upper part of the electronic circuit unit 3, and the on-board charger 32 is disposed on the upper and lower parts of the electronic circuit unit 3.

[0021] In this way, by including not only the inverter 33 but also the on-board charger 32 in the electronic circuit 31 included in the electronic circuit unit 3, the vehicle drive device A can be further miniaturized. Note that the layout of the electronic circuit 31 mounted on the electronic circuit unit 3 shown in Figs. 2 to 4 is one example, and the layout of the electronic circuit 31 can be changed as appropriate. The electronic components (electronic circuit 31) mounted on the board 35 are cooled by a cooling plate 36 that configures a part of a second flow path 55 of a cooling flow path B described later inside the electronic circuit 31. In this way, the electronic circuit unit 3 (power supply module 100) is configured to be coolable by the cooling fluid flowing through the cooling flow path B.

[0022] As shown in FIG. 3 to FIG. 5, the vehicle drive device A is configured to include an integrated unit 1 in which a vehicle drive unit 2 and an electronic circuit unit 3 are integrated, a cooling flow path B for circulating a cooling fluid to the electronic circuit unit 3 (power supply module 100), an oil flow path C for circulating oil to the vehicle drive unit 2, and a refrigerant flow path D for circulating a refrigerant for heating and cooling the interior of the vehicle. In the cooling flow path B, a cooling liquid such as cooling water or insulating oil, such as an antifreeze liquid mainly composed of ethylene glycol or the like, or a long-life coolant, flows as a cooling fluid. In the refrigerant flow path D, a refrigerant (cooling fluid) such as hydrofluorocarbon (HFC) or hydrofluoroolefin (HFO) flows. In the cooling flow path B, a refrigerant may be circulated as a cooling fluid instead of a cooling liquid, and heat may be exchanged between the oil and the refrigerant. In other words, the vehicle drive device A may unify the cooling fluid flowing through the cooling flow path B and the refrigerant flow path D into the refrigerant by circulating the refrigerant through the cooling flow path B.

[0023] The cooling flow path B will be described. The cooling flow path B is a flow path shown above the electric motor 21 in FIG. 5. The cooling flow path B includes the valve unit 6, the power module 100, an oil cooler 62 (an example of a first heat exchanger) described later, a water-cooled condenser 81 (an example of a second heat exchanger), a radiator 53, and the like along the way. The cooling flow path B has a first flow path 54 extending from the water-cooled condenser 81 to the radiator 53, and a second flow path 55 extending from the radiator 53 to the water-cooled condenser 81. In the electronic circuit unit 3, a part of the second flow path 55 of the cooling flow path B is formed as an internal flow path of the cooling plate 36. A part of the cooling flow path B is disposed inside the unit case 5.

[0024] The cooling flow path B circulates the coolant (one example of a cooling fluid) in the order of the power supply module 100 (electronic circuit unit 3), the oil cooler 62, the water-cooled condenser 81, and the radiator 53. In addition, the cooling flow path B has a valve 52 arranged in a first flow path 54 that supplies the coolant to the radiator 53, which can be switched between a first state in which the coolant flows through the radiator 53 and a second state in which the coolant is blocked from flowing into the radiator 53 and is diverted. As a result, the cooling flow path B can be switched by the valve 52 between a flow path 56 in which the coolant passes through the radiator 53 and merges with the second flow path 55, and a flow path 57 in which the coolant flows without passing through the radiator 53 and merges with the second flow path 55. In the cooling flow path B, the water pump 51 is arranged downstream of the valve 52 and the radiator 53. The cooling passage B also has a passage 58 leading from the electronic circuit unit 3 to the oil cooler 62 and a passage 59 leading from the oil cooler 62 to the water-cooled condenser 81 .

[0025] Next, the oil flow path C will be described. The oil flow path C is a flow path shown below the electronic circuit unit 3 in Fig. 5. The oil flow path C includes an oil pump 61 and an oil cooler 62 midway through the flow path, and supplies oil to the electric motor 21 and the like to circulate the oil in the vehicle drive unit 2. The oil cooler 62 is located downstream of the power source module 100 (electronic circuit unit 3) in the cooling flow path B, and exchanges heat between the coolant circulating through the cooling flow path B and the oil.

[0026] Next, the refrigerant flow path D will be described. The refrigerant flow path D is a flow path shown on the right side in FIG. 5, and is configured to circulate a refrigerant for heating and cooling. The refrigerant flow path D includes a heating flow path 71 that circulates a refrigerant for heating the interior of the vehicle, a cooling flow path 72 that circulates a refrigerant for cooling the interior of the vehicle, and a battery cooling flow path 73 that circulates a refrigerant to cool a battery 87 mounted on the vehicle. The heating flow path 71 includes a water-cooled condenser 81, an accumulator 82, a compressor 83, and a cabin condenser 84 (heating condenser) arranged in this order to configure a heat pump as a whole. The refrigerant flow path D includes a water-cooled condenser 81 in the middle of the flow path that exchanges heat with the cooling liquid circulating in the cooling flow path B. The water-cooled condenser 81 is located downstream of the oil cooler 62 in the cooling flow path B, and exchanges heat between the cooling liquid circulating in the cooling flow path B and the refrigerant.

[0027] In the heating flow path 71, an on-off valve 91 is disposed in the flow path 74 between the water-cooled condenser 81 and the accumulator 82, and a first expansion valve 92 is disposed in the flow path 76 between the cabin condenser 84 and the water-cooled condenser 81. In the example shown in FIG.

[0028] The cooling flow path 72 is composed of a flow path 77 branching off from the flow path 74 on the upstream side of the on-off valve 91. The flow path 77 is configured to include a second expansion valve 93 and an evaporator 85 in that order midway through the flow path, and to merge with the flow path 74 on the downstream side of the on-off valve 91. In other words, when the second expansion valve 93 is driven with the on-off valve 91 closed, the refrigerant flows through the flow path 77, and the evaporator 85 cools the vehicle interior. In the example shown in FIG. 5, the evaporator 85 is disposed outside the unit case 5 in the cooling flow path 72.

[0029] The battery cooling flow path 73 is composed of a flow path 78 branching from the upstream side of the second expansion valve 93 of the flow path 77 of the cooling flow path 72. The flow path 78 is configured to include a third expansion valve 94 and a chiller 86 in this order in the middle of the flow path, and to merge with the downstream side of the evaporator 85 of the flow path 77. In other words, when the third expansion valve 94 is driven with the opening / closing valve 91 closed, the refrigerant flows through the flow path 78, and the chiller 86 exchanges heat between the refrigerant and the cooling liquid circulating through the cooling circuit 79. In the refrigerant flow path D, it is preferable that the opening / closing valve 91, the first expansion valve 92, the second expansion valve 93, and the third expansion valve 94 are modularized and integrated with the cooling module 4.

[0030] Furthermore, chiller 86 disposed in battery cooling flow path 73 is also disposed in cooling circulation path 79 that circulates coolant to battery 87. A water pump 88 is disposed midway through cooling circulation path 79. Battery 87 is disposed in the battery cooling flow path 73, for example, in the space under the vehicle floor located outside and rearward of unit case 5.

[0031] [Cooling plate] As shown in Fig. 3 and Fig. 4, the second space 12 of the unit case 5 houses a cooling plate 36 for cooling the power supply module 100 and the electronic circuit unit 3. The cooling plate 36 is made of a metal with high thermal conductivity such as aluminum, and is integrally formed by joining a plate-shaped lower plate 36a and an upper plate 36b by a method such as welding. A space is formed inside the cooling plate 36 (between the lower plate 36a and the upper plate 36b), and a cooling liquid flows through the space. By exchanging heat between the power supply module 100 and the cooling liquid, the temperature of the power supply module 100 is lowered and the temperature of the cooling liquid is raised.

[0032] 3 and 4, the second flow passage 55 of the cooling plate 36 is disposed in a horizontal direction. In this embodiment, the cooling liquid flows in through the inlet 37 of the cooling plate 36 and flows out through the outlet 38.

[0033] 6 and 7, the oil cooler 62 is formed in a box shape having, for example, an upper surface 62A on the side of the electronic circuit 31 and a lower surface 62B on the side of the electric motor 21. The oil cooler 62 has a coolant inlet 63 on the upper surface 62A through which coolant flows in from above, and a coolant outlet 64 on the lower surface 62B that extends toward the side of the oil cooler 62 and through which the coolant flows out. The oil cooler 62 also has an oil inlet 66 through which oil flows in and an oil outlet 67 through which the oil flows out, individually on the lower surface 62B.

[0034] The oil cooler 62 is engaged with the cooling plate 36 in a concave-convex manner while being disposed in the second space 12. Specifically, the outlet 38 formed in the lower plate 36a of the cooling plate 36 is a cylindrical portion protruding downward, and the outlet 38 of the cooling plate 36 is inserted and fitted into the cooling liquid inlet 63 of the oil cooler 62. Although not shown, the cooling liquid inlet 63 of the oil cooler 62 may be configured as a cylindrical portion protruding upward, and the outlet 38 of the cooling plate 36 may be configured as an opening. In this case, the cooling liquid inlet 63 (cylindrical portion) of the oil cooler 62 is inserted and fitted into the outlet 38 of the cooling plate 36. The oil cooler 62 has a support plate P joined to a lower surface 62B, and is positioned relative to the partition wall S and fastened to the partition wall S by screw members 40 or the like (see also FIG. 4). Similarly, the electronic circuit unit 3 including the cooling plate 36 is positioned relative to the partition wall S and fastened to the partition wall S by screws 41 or the like (see also FIG. 4).

[0035] 7, in the present embodiment, the oil cooler 62 has a coolant inlet 63 and a coolant outlet 64, and an oil inlet 66 and an oil outlet 67, which are arranged diagonally on a plane projected along the lower plate 36a of the cooling plate 36. Specifically, on a plane projected along the lower plate 36a of the cooling plate 36, the coolant inlet 63 is arranged closer to the X1 direction and the Y1 direction, and the coolant outlet 64 is arranged closer to the X2 direction and the Y2 direction. Similarly, on a plane projected along the lower plate 36a, the oil inlet 66 is arranged closer to the X2 direction and the Y1 direction, and the oil outlet 67 is arranged closer to the X1 direction and the Y2 direction.

[0036] As shown in FIG. 8, the oil cooler 62 and the water-cooled condenser 81 are disposed at positions facing each other across the wall (side surface 5A) of the unit case 5. As shown in FIG. 3, the water-cooled condenser 81 is attached to a position on the side surface 5A of the unit case 5 close to the oil cooler 62. A flow path portion 65 is provided between the cooling liquid outlet 64 and the water-cooled condenser 81. In the example shown in FIG. 3, the flow path portion 65 includes a first portion 65a formed along the wall surface of the partition wall S, a second portion 65b bent from the lower surface 62B toward the upper surface 62A, and a third portion 65c extending in the same direction as the first portion 65a and continuing from the inside to the outside of the unit case 5. That is, the third portion 65c is formed to penetrate the side surface 5A of the unit case 5 and is connected to the inside of the water-cooled condenser 81.

[0037] As shown in FIG. 8, the flow path portion 65 may be configured to have only a first portion 65a along the partition wall S between the cooling liquid outlet 64 of the oil cooler 62 and the water-cooled condenser 81, without having a second portion 65b and a third portion 65c.

[0038] In this way, by arranging the oil cooler 62 and the water-cooled condenser 81 close to each other and providing a flow path section 65 between the cooling liquid outlet 64 and the water-cooled condenser 81, the cooling liquid piping section (flow path section 65) connected to the oil cooler 62 does not occupy a large area of ​​the oil cooler 62 in the vertical direction, and the integrated unit 1 can be made compact even when the oil cooler 62 is disposed between the vehicle drive unit 2 and the electronic circuit unit 3 (power supply module 100).

[0039] 3 and 4, a supply unit 68 that supplies oil toward the electric motor 21 is connected to an oil outlet 67 of the oil cooler 62, and is arranged so that the oil flowing out from the supply unit 68 flows out from the lower surface 62B of the oil cooler 62 toward the electric motor 21. In this way, the oil flows out from the lower surface 62B of the oil cooler 62 toward the electric motor 21.

[0040] 4, 9, and 10, the water pump 51 is fixed to the side surface 5A of the unit case 5 at a position where the water pump 51 overlaps at least a portion of the cooling plate 36 in a side view. As shown in Fig. 4, the water pump 51 is disposed on the same side as the radiator 53 with respect to the integrated unit 1.

[0041] 9 and 10, the water pump 51 has a coolant intake port 51a and a coolant discharge port 51b, and is disposed such that the coolant discharge port 51b overlaps at least a portion of the cooling plate 36 in a side view. Specifically, the coolant discharge port 51b of the water pump 51 is positioned within the width W of the cooling plate 36 in the up-down direction.

[0042] 4, the coolant discharge port 51b of the water pump 51 and the inlet 37 of the cooling plate 36 are connected by a connection flow path 39. The connection flow path 39 is provided below the cooling plate 36 and is formed along the bottom surface of the cooling plate 36 (lower plate 36a).

[0043] Second Embodiment In the first embodiment, an example has been described in which the refrigerant manifold 4a and the water-cooled condenser 81 are integrated and disposed outside the unit case 5. Alternatively, as shown in Fig. 11, the refrigerant manifold 4a and the water-cooled condenser 81 may be separated and individually assembled to the integrated unit 1. Specifically, as shown in Fig. 11, the integrated unit 1 has the refrigerant manifold 4a, which includes a refrigerant flow path D through which the refrigerant flows, located above and separated from the water-cooled condenser 81, and the water-cooled condenser 81 is connected to the unit case 5 from a lateral side.

[0044] By connecting the water-cooled condenser 81 to the unit case 5 from the lateral side as in this embodiment, the piping length between the oil cooler 62 and the water-cooled condenser 81 can be shortened, and the vehicle drive device A can be made compact.

[0045] [Other embodiments] (1) In the above embodiment, an example is shown in which the water pump 51 and the valve 52 are integrated into the cooling passage B. However, the water pump 51 and the valve 52 may be configured separately, or the water pump 51 and the valve 52 may be housed in separate housings. (2) The flow directions of the coolant and refrigerant, and the flow directions of the coolant and oil, which are involved in heat exchange, may be either the same direction or opposite directions. (3) In the integrated unit 1 in the above-described embodiment, the vehicle drive unit 2 and the electronic circuit unit 3 are housed in a unit case 5 and integrated together. However, the vehicle drive unit 2 and the electronic circuit unit 3 may be housed in different cases and the cases may be connected together. (4) In the above embodiment, the oil cooler 62 has the coolant inlet 63 provided on the upper surface 62A and the coolant outlet 64 provided on the lower surface 62B. Alternatively, the oil cooler 62 may have both the coolant inlet 63 and the coolant outlet 64 provided on the upper surface 62A.

[0046] [Summary of the above embodiment] Hereinafter, in the above-described embodiment, the following configurations are envisioned. <1> One embodiment of the vehicle drive device (A) includes an integrated unit (1) in which an electric vehicle drive unit (2) including at least an electric motor (21) that transmits drive torque to the vehicle's running system, and an electronic circuit unit (3) including at least an electronic circuit (31) for driving the electric motor (21), are built into a housing (5) and integrated with the electric motor (21), a cooling plate (36) to which the electronic circuit unit (3) is fixed and through which a coolant flows, and a water pump (51) that circulates the coolant inside the cooling plate (36), and the water pump (51) is fixed to an outer surface (5A) of the housing (5) in a position overlapping at least a portion of the cooling plate (36) in a side view.

[0047] In this configuration, the vehicle drive device (A) includes an integrated unit (1) that integrates the electric vehicle drive unit (2) and the electronic circuit unit (3), and therefore can be made smaller than when the electric vehicle drive unit (2) and the electronic circuit unit (3) are arranged separately.

[0048] In this configuration, the water pump (51) is fixed to the outer surface (5A) of the housing (5) at a position overlapping at least a portion of the cooling plate (36) in a side view. This allows the coolant to circulate between the cooling plate (36) and the water pump (51) inside the integrated unit (1). This also makes it possible to shorten the length of the piping connecting the cooling plate (36) and the water pump (51), thereby suppressing heat radiation through the piping and improving the heat recovery rate.

[0049] In this way, the vehicle drive device (A) is compact and capable of efficient heat management.

[0050] <2> The water pump (51) is preferably arranged on the same side of the integrated unit (1) as the radiator (53).

[0051] As in this configuration, if the water pump (51) is arranged on the same side of the integrated unit (1) as the radiator (53), the piping between the water pump (51) and the radiator (53) can be shortened, and the vehicle drive device (A) can be made compact.

[0052] <3> The water pump (51) has a coolant suction port (51a) and a coolant discharge port (51b), and is preferably positioned so that the coolant discharge port (51b) overlaps at least a portion of the cooling plate (36) in a side view.

[0053] According to this configuration, it is possible to shorten the length of the piping between the cooling plate (36) and the coolant discharge port (51b) of the water pump (51), thereby reducing pressure loss in the cooling flow path (B) and enabling the coolant to circulate more efficiently.

[0054] <4> The water pump (51) has a coolant suction port (51a) and a coolant discharge port (51b), and a connection flow path (39) between the coolant discharge port (51b) and the cooling plate (36) is preferably formed along the bottom surface of the cooling plate (36).

[0055] As in this configuration, if the connecting flow path (39) between the coolant discharge port (51b) of the water pump (51) and the cooling plate (36) is formed along the bottom surface of the cooling plate (36), the piping length between the water pump (51) and the cooling plate (36) can be shortened, and the vehicle drive device (A) can be made compact. [Industrial Applicability]

[0056] The present invention can be widely used in vehicle drive devices for electric vehicles. [Explanation of symbols]

[0057] 1: integrated unit, 2: drive unit for electric vehicle, 3: electronic circuit unit, 5: unit case (housing), 5A: side (outer surface), 21: electric motor, 31: electronic circuit, 36: cooling plate, 39: connecting flow path, 51: water pump, 51a: coolant intake port, 51b: coolant discharge port, 53: radiator, A: vehicle drive device

Claims

1. an integrated unit in which an electric vehicle drive unit including at least an electric motor that transmits a drive torque to a running system of the vehicle and an electronic circuit unit including at least an electronic circuit for driving the electric motor are built into a housing and integrated; a cooling plate to which the electronic circuit unit is fixed and through which a cooling liquid flows; a water pump that circulates the cooling liquid inside the cooling plate; The water pump is fixed to an outer surface of the housing at a position overlapping at least a portion of the cooling plate in a side view of the vehicle drive device.

2. 2. The vehicle drive system according to claim 1, wherein the water pump is disposed on the same side as a radiator with respect to the integrated unit.

3. 2. The vehicle drive device according to claim 1, wherein the water pump has a coolant suction port and a coolant discharge port, and the coolant discharge port is disposed so as to overlap at least a portion of the cooling plate in the side view.

4. The water pump has a coolant intake port and a coolant discharge port, The vehicle drive device according to claim 1 , wherein a connection flow path between the coolant discharge port and the cooling plate is formed along a bottom surface of the cooling plate.

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