Drive device

Abstract

To provide a drive device which enables improvement of heat exchange efficiency between a lubrication oil of a transmission and a refrigerant.SOLUTION: A drive device includes: a motor 10 housed in a motor housing 11; and a transmission (a speed reducer 20) which is housed in a speed reducer housing 21 and changes a speed of rotation of the motor 10 to output the rotation. The speed reducer housing 21 and the motor housing 11 are integrally connected in a rotary shaft 24 direction. The speed reducer housing 21 has: a refrigerant inlet 26; and a first refrigerant passage (a speed reducer side refrigerant passage 25) formed around the speed reducer 20 including a bottom part of the speed reducer housing 21. The motor housing 11 has a second refrigerant passage (a motor side refrigerant passage 15) which communicates with the speed reducer side refrigerant passage 25 and is formed around the motor 10. An oil pan 210 serving as a storage part in which a lubrication oil for lubricating the speed reducer 20 is stored is formed at the bottom part of the speed reducer housing 21.SELECTED DRAWING: Figure 1

Description

[Technical field]

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

[0002] A drive unit in which a motor and a transmission are integrated is known as a device used in electric vehicles, hybrid vehicles, etc. In general, the motor is cooled by a refrigerant, and the transmission is lubricated and cooled by lubricating oil.

[0003] Patent Document 1 discloses a drive device in which a refrigerant flow path in a housing communicates with a partition between a motor and a reducer, and lubricating oil for the reducer is cooled by the refrigerant flowing through the partition. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2021 / 229697 Summary of the Invention

[0005] In the housing of the conventional technology, a partition portion is located away from the inlet and outlet of the refrigerant flow path, which reduces the heat exchange efficiency due to pressure loss of the refrigerant, and causes problems such as insufficient heat exchange with the lubricating oil in the transmission.

[0006] The present invention has been made in consideration of such problems, and aims to provide a drive device that can improve the heat exchange efficiency between the refrigerant in the refrigerant flow path and the lubricating oil of the transmission in a configuration in which the motor and transmission are integrally formed.

[0007] One embodiment of the present invention is applied to a drive device including a motor housed in a motor housing and a transmission housed in a transmission housing for changing the speed of the rotation of the motor and outputting the rotation, the transmission housing and the motor housing being integrally connected in the direction of the rotation axis. The transmission housing has a refrigerant inlet and a first refrigerant flow path formed around the transmission including the bottom of the transmission housing, and the motor housing has a second refrigerant flow path communicating with the first refrigerant flow path and formed around the motor. A reservoir is formed in the bottom of the transmission housing to store lubricating oil for lubricating the transmission.

[0008] According to the present invention, the transmission housing is provided with a refrigerant inlet, and the refrigerant flows from the transmission to the motor, so that heat exchange occurs between the refrigerant that has just flowed in from the refrigerant inlet and the lubricating oil of the transmission. In addition, the first refrigerant flow path is formed around the transmission housing, including the reservoir, so that sufficient heat exchange can be performed between the refrigerant and the lubricating oil. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a vertical cross-sectional view of a drive device according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a cross-sectional view of the reducer taken along line II-II. [Diagram 3] FIG. 3 is an explanatory diagram of a refrigerant flow path of the drive device. [Figure 4] FIG. 4 is an explanatory diagram of a refrigerant flow path of a driving device according to a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0011] FIG. 1 is a vertical cross-sectional view of a drive device 1 for a vehicle according to the present embodiment.

[0012] The drive unit 1 includes a motor 10 as a rotating electric machine, a reducer 20 that reduces the rotation of the motor 10 and outputs it, and a power conversion device 30 that supplies power to the motor 10. The drive unit 1 is mounted on a vehicle and drives the vehicle by rotating drive wheels using the rotation of the motor 10. Note that the drive unit 1 may also be used as a drive unit for devices other than vehicles, for example, various electric devices or industrial machines.

[0013] 1, the motor 10 and the power conversion device 30 are housed in a motor chamber 110 formed by a motor housing 11. The reducer 20 is housed in a reducer chamber 200 formed by a reducer housing 21. The motor housing 11 and the reducer housing 21 are connected in the axial direction, and the motor chamber 110 and the reducer chamber 200 are defined by a partition wall 19 extending from an end of the motor housing 11 toward the inner diameter side.

[0014] The motor housing 11 and the reducer housing 21 are formed by casting using a metal material such as an aluminum alloy.

[0015] The motor 10 includes a stator 12, a rotor 13, and a rotor shaft 14. The motor 10 rotates by power supplied from a power conversion device 30. The motor 10 also functions as a generator that receives driving force due to the rotation of the drive wheels and generates electricity (regenerates electricity).

[0016] The rotor shaft 14 is formed as a hollow shaft, and a rotating shaft 24 is disposed penetrating the inner periphery of the rotor shaft 14. The rotating shaft 24 penetrates the rotor shaft 14 of the motor 10, extends to the left and right sides of the drive unit 1, and is connected to a drive wheel (not shown).

[0017] The motor chamber 110 is formed by a cylindrical motor housing 11, a cover 16 closing one end (the right side in FIG. 1) of the motor housing 11, and a partition wall 19 closing the other end (the left side in FIG. 1) of the motor housing 11. One end of the rotating shaft 24 passes through the cover 16 and is connected to a drive wheel (not shown). The other ends of the rotor shaft 14 and the rotating shaft 24 pass through the partition wall 19 and are connected to the reducer 20.

[0018] The reduction gear 20 includes a reduction mechanism 22 and a differential gear 23. The reduction mechanism 22 is configured, for example, by a planetary gear mechanism, and reduces the rotation transmitted from the rotor shaft 14 of the motor 10 and transmits it to a rotating shaft 24. The rotating shaft 24 is connected to one side of the differential gear 23, and a second-side axle 241 is disposed on the other side of the differential gear 23. The differential gear 23 transmits the rotation while allowing a rotation difference therebetween.

[0019] The reducer chamber 200 is formed by a cylindrical reducer housing 21 , a cover 28 that closes the other end side of the reducer housing 21 , and a partition wall 19 formed in the motor housing 11 .

[0020] The reduction gear chamber 200 stores lubricating oil for lubricating the reduction gear 20. The bottom of the reduction gear chamber 200 is configured as an oil pan 210 in which the lubricating oil is stored (see FIG. 2). The lubricating oil is scooped up inside the reduction gear chamber 200 by the rotation of the gears of the reduction gear mechanism 22 and the differential gear 23, and flows down into the oil pan 210 while lubricating the reduction gear mechanism 22 and the differential gear 23.

[0021] In this embodiment, the drive device 1 is described as having a configuration including the motor 10 and the reducer 20, but the reducer 20 may be replaced with a speed increaser that increases the rotation speed of the motor 10. In other words, it is sufficient that the drive device 1 is provided with a transmission that changes the gear ratio.

[0022] The power conversion device 30 is disposed in the motor chamber 110, and converts DC power supplied from a battery (not shown) into power suitable for driving the motor 10 and supplies the power to the motor 10. During regeneration of the motor 10, the power conversion device 30 converts the regenerative power into power suitable for charging the battery, and charges the battery.

[0023] Next, the cooling circuit 100 of the drive unit 1 configured as above will be described.

[0024] In this embodiment, as described above, the motor 10 and the reducer 20 are connected by a single shaft, and the rotation of the motor 10 is slowed down by the reduction mechanism 22, which is made up of a planetary gear mechanism that can achieve a large reduction ratio. With this configuration, the drive device 1 can be made smaller than with a configuration that employs a reduction mechanism made up of two or three shafts.

[0025] On the other hand, since the rotation of each gear constituting the reduction mechanism 22 becomes larger as a result of the increase in the reduction ratio of the reduction mechanism 22 compared to a reduction mechanism constituted by two or three shafts, the temperature of the reduction mechanism 22 tends to rise easily. For this reason, the reduction mechanism 22 needs to be appropriately cooled.

[0026] In this embodiment, the cooling circuit 100 is configured as follows, so that heat exchange is appropriately performed between the lubricating oil and the refrigerant of the reduction gear 20, thereby enabling the reduction mechanism 22 to be sufficiently cooled.

[0027] The reducer housing 21 is provided with a reducer side refrigerant flow path 25 as a first refrigerant flow path through which a refrigerant (e.g., cooling water) flows. The motor housing 11 is provided with a motor side refrigerant flow path 15 as a second refrigerant flow path through which a refrigerant flows.

[0028] The reducer side refrigerant flow path 25 is formed as an arc-shaped flow path surrounding the reducer 20 inside the reducer housing 21, and is configured so that the refrigerant flows around the reduction mechanism 22 and the oil pan 210. A refrigerant inlet 26 that allows the refrigerant to flow into the reducer side refrigerant flow path 25 is provided at the top of the reducer housing 21.

[0029] The motor-side refrigerant flow passage 15 is formed so as to spirally surround the motor 10 and the power conversion device 30 (see FIG. 3). The refrigerant is configured to flow in a spiral shape from the reducer 20 side toward one end side of the motor housing 11 (the right side in FIG. 1). A refrigerant outlet 27 through which the refrigerant flows out from the motor-side refrigerant flow passage 15 is provided at an upper portion of the one end side of the motor housing 11. Note that the refrigerant may be configured to flow in from the refrigerant outlet 27, pass through the motor housing 11 and the reducer housing 21, and flow out from the refrigerant inlet 26.

[0030] The outer shape of the reducer housing 21 is configured to be larger than the outer shape of the motor housing 11. As described above, the outer shapes of the reducer housing 21 and the motor housing 11 are cylindrical, and the reducer housing 21 is formed to be larger than the motor housing 11. The partition wall 19 also includes a partition wall refrigerant flow path 31 as a third refrigerant flow path that allows the refrigerant to flow from the reducer side refrigerant flow path 25 to the motor side refrigerant flow path 15 in a direction perpendicular to the rotation shaft 24. With this configuration, the partition wall refrigerant flow path 31 is configured to allow the refrigerant to flow from the reducer side refrigerant flow path 25 formed in the reducer housing 21, which has a larger outer shape, to the motor side refrigerant flow path 15 of the motor housing 11, which has a smaller outer shape, in a direction perpendicular to the rotation shaft 24.

[0031] In this way, the refrigerant that flows into the driving device 1 from the refrigerant inlet 26 passes through the reducer side refrigerant flow path 25, the partition wall refrigerant flow path 31, and the motor side refrigerant flow path 15, and flows out from the refrigerant outlet 27. In this way, the cooling circuit 100 is formed.

[0032] Next, the configuration of the cooling circuit 100 thus configured will be described in detail.

[0033] FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1, showing the reducer 20 as viewed from the direction of the rotation axis.

[0034] The reducer 20 is configured by accommodating a reduction mechanism 22 in a substantially cylindrical reducer housing 21. A refrigerant inlet 26 is provided at an upper portion of the reducer housing 21 (slightly to the left in FIG. 2 ), and communicates with a reducer-side refrigerant flow path 25 in the reducer housing 21.

[0035] 2, the reducer side refrigerant flow path 25 extends in an arc shape (C-shape) from the refrigerant inlet 26 along the outer periphery of the reducer housing 21 so as to surround the periphery of the reduction mechanism 22. The lower end of the reducer side refrigerant flow path 25 extends circumferentially from the upper side of the rotating shaft 24 to the lower side of the rotating shaft 24, and is formed from the 11 o'clock to 7 o'clock directions as viewed from the center of the rotating shaft 24. The reducer side refrigerant flow path 25 communicates with a partition wall refrigerant flow path 31 formed in the partition wall 19 via a communication path 25a that penetrates in the direction of the rotating shaft 24.

[0036] The partition wall refrigerant flow path 31 is formed in an annular shape in the partition wall 19, as indicated by a dotted line in Fig. 2. The partition wall refrigerant flow path 31 communicates with the motor side refrigerant flow path 15 at its inner periphery, as indicated in Fig. 1. In this manner, the partition wall refrigerant flow path 31 communicates the refrigerant in the partition wall 19, from the reducer side refrigerant flow path 25 to the motor side refrigerant flow path 15, in a direction perpendicular to the rotation shaft 24.

[0037] With this configuration, in the reducer 20, heat exchange occurs between the refrigerant flowing through the reducer side refrigerant flow passage 25 formed in the circumferential direction of the reducer housing 21, the refrigerant flowing through the partition wall refrigerant flow passage 31 formed in the partition wall 19 of the motor housing 11, and the lubricating oil of the reducer 20. This cools the lubricating oil.

[0038] In particular, the refrigerant with the lowest temperature before heat exchange flows through the reduction gear 20, so that the lubricating oil in the reduction gear 20 can be sufficiently cooled. Also, when warming up is required, such as for a cold start of the vehicle, the refrigerant with the highest temperature before heat exchange flows through the reduction gear 20, so that heat exchange occurs between the lubricating oil stored in the oil pan 210 of the reduction gear 20 and this refrigerant, so that the lubricating oil can be sufficiently warmed up.

[0039] 2, in the reducer 20, an oil catch tank 32 is provided on the side of the partition wall 19 facing the reducer chamber 200 (shown by a dashed line in FIG. 2). The oil catch tank 32 temporarily stores lubricating oil scooped up by the rotation of the reduction mechanism 22 in the reducer 20.

[0040] The oil catch tank 32 is formed only above the rotating shaft 24 in the partition wall 19. That is, it is formed from the 11 o'clock direction to the 3 o'clock direction centered on the rotating shaft 24. The oil catch tank 32 is configured to overlap with the partition wall refrigerant flow path 31 in the direction of the rotating shaft 24, via the partition wall 19.

[0041] 1, the oil catch tank 32 comprises a bottom 32a formed to rise in the axial direction from the partition wall 19 toward the reducer chamber 200, and a wall 32b extending upward from the end of the bottom 32a, forming a gutter-like structure with the bottom 32a, the wall 32b, and the inner wall of the partition wall 19. With this structure, the lubricating oil scooped up to the upper part of the reducer chamber 200 by the rotation of the reduction mechanism 22 in the direction of the solid arrow as shown in FIG.

[0042] At this time, the lubricating oil temporarily stored in the oil catch tank 32 exchanges heat with the refrigerant in the reducer-side refrigerant flow path 25 arranged around the oil catch tank 32. Furthermore, since the oil catch tank 32 is in contact with the partition wall refrigerant flow path 31 via the partition wall 19, heat exchange occurs between the lubricating oil temporarily stored in the oil catch tank 32 and the refrigerant flowing through the partition wall refrigerant flow path 31. The lubricating oil stored in the oil catch tank 32 then flows down from the right side in FIG. 2 into the oil pan 210.

[0043] The refrigerant usually contains antifreeze, and the temperature of the refrigerant flowing into the reducer side refrigerant flow passage 25 is controlled to about 65° C. The refrigerant flowing through the reducer side refrigerant flow passage 25 exchanges heat with the lubricating oil temporarily stored in the oil catch tank 32 across the partition wall 19, thereby cooling the lubricating oil. When warming up is required, such as for a cold start of the vehicle, the refrigerant flowing through the reducer side refrigerant flow passage 25 formed up to the bottom of the reducer housing 21 exchanges heat with the lubricating oil stored in the oil pan 210 across the partition wall 19, thereby warming up the lubricating oil.

[0044] Next, the motor side refrigerant flow path 15, the speed reducer side refrigerant flow path 25, and the partition wall refrigerant flow path 31 will be described in detail with reference to FIG.

[0045] The motor housing 11 is composed of a cylindrical inner cylinder 111 and an outer cylinder 112. A groove 111a is formed on the outer circumferential surface of the inner cylinder 111. The outer cylinder 112 is fitted onto the inner cylinder 111, and a space formed by the groove 111a and the outer cylinder 112 is formed as a motor-side refrigerant flow path 15. The groove 111a is formed in a spiral shape on the outer circumferential surface of the inner cylinder 111.

[0046] Similarly, the reducer housing 21 is composed of a cylindrical inner cylinder 211 and an outer cylinder 212. A groove 211a is formed on the outer circumferential surface of the inner cylinder 211. The outer cylinder 212 is fitted to the inner cylinder 211, and a space formed by the groove 211a and the outer cylinder 212 is formed as a reducer side refrigerant flow path 25.

[0047] At the end of the groove 211a, a communication passage 25a is formed which communicates with the partition wall refrigerant passage 31 formed in the partition wall 19. The communication passage 25a is disposed between the reducer housing 21 and the motor housing 11. An O-ring may be fitted in the communication passage 25a to prevent leakage of cooling water. As shown in Fig. 2, the partition wall refrigerant passage 31 is formed in an annular shape centered on the rotating shaft 24, and communicates with the motor side refrigerant passage 15 on its inner peripheral side.

[0048] FIG. 4 is an explanatory diagram of the motor side refrigerant flow path 15, the reducer side refrigerant flow path 25, and the partition wall refrigerant flow path 31 in a modified example of this embodiment.

[0049] In the modified example shown in FIG. 4, the configuration of the reducer side refrigerant flow passage 25 is different from the configuration shown in FIG.

[0050] The inner cylinder 211 of the reducer housing 21 has a first groove portion 211b and a second groove portion 211c. The first groove portion 211b is formed in an arc shape from the refrigerant inlet 26 along the outer periphery of the reducer housing 21 as shown in Fig. 2, and its end is formed in the 7 o'clock direction as viewed from the center of the rotating shaft 24. The second groove portion 211c is folded back from the end of the first groove portion 211b and formed in an arc shape along the outer periphery of the reducer housing 21. The end of the second groove portion 211c is formed near the refrigerant inlet 26, and a communication passage 25a communicating with the partition wall refrigerant flow path 31 is formed at this end.

[0051] In this way, by forming the first groove portion 211b and the second groove portion 211c in the inner cylinder 211, the reducer side refrigerant flow passage 25 can be configured to be folded back in the circumferential direction along the outer periphery of the reducer housing 21. This makes it possible to extend the time during which heat is exchanged between the reduction mechanism 22 and the lubricating oil and the refrigerant, and improves the heat exchange efficiency, compared to the reducer side refrigerant flow passage 25 described in Figures 1 to 3. Note that the configuration in Figure 4 may also be configured such that the refrigerant flows in from the refrigerant outlet 27, passes through the motor housing 11 and the reducer housing 21, and flows out from the refrigerant inlet 26.

[0052] As described above, the drive device 1 of this embodiment includes the motor 10 housed in the motor housing 11, and the transmission (reduction gear 20) housed in the reduction gear housing 21 for changing the speed of the rotation of the motor 10 and outputting it, and is configured by integrally connecting the reduction gear housing 21 and the motor housing 11 in the direction of the rotation shaft 24. The reduction gear housing 21 has a refrigerant inlet 26 and a first refrigerant flow path (reduction gear side refrigerant flow path 25) formed around the reduction gear 20 including the bottom of the reduction gear housing 21. The motor housing 11 has a second refrigerant flow path (motor side refrigerant flow path 15) that communicates with the reduction gear side refrigerant flow path 25 and is formed around the motor 10. An oil pan 210 is configured at the bottom of the reduction gear housing 21 as a reservoir for storing lubricating oil for lubricating the reduction gear 20.

[0053] In this configuration, a refrigerant inlet 26 is provided in the reducer housing 21 on the reducer 20 side, and the refrigerant flows from the reducer side refrigerant flow path 25 of the reducer 20 toward the motor 10, so that the reducer 20 exchanges heat between the refrigerant that has just flowed in from the refrigerant inlet 26 and the lubricating oil. And, since the reducer side refrigerant flow path 25 is formed around the reducer housing 21, including the oil pan 210, sufficient heat exchange can be performed between the refrigerant and the lubricating oil stored in the oil pan 210. This can increase the efficiency of heat exchange between the refrigerant and the lubricating oil.

[0054] In this embodiment, the reducer housing 21 and the motor housing 11 are separated by a partition wall 19 formed in a direction perpendicular to the rotation shaft 24, and an oil catch tank 32 is formed on the reducer 20 side of the partition wall 19 to temporarily store lubricating oil scooped up by the gears of the reducer 20. The partition wall 19 has a partition wall refrigerant flow path 31 as a third refrigerant flow path that communicates between the reducer side refrigerant flow path 25 and the motor side refrigerant flow path 15 and is formed so that the refrigerant flows at a position adjacent to the oil catch tank 32 and the storage portion.

[0055] In this configuration, when the lubricating oil scooped up by the reducer 20 is temporarily stored in the oil catch tank 32, heat exchange occurs between the lubricating oil and the refrigerant flowing through the partition wall refrigerant flow path 31 adjacent to the oil catch tank 32, so that the lubricating oil can be cooled more appropriately.

[0056] In addition, in this embodiment, the reducer housing 21 and the motor housing 11 are formed in a cylindrical shape, the outer shape of the reducer housing 21 is configured to be larger than the outer shape of the motor housing 11, and the partition wall refrigerant flow path 31 is configured to extend in a direction perpendicular to the rotating shaft 24.

[0057] In this configuration, the refrigerant can flow in the partition wall refrigerant flow path 31 in a direction perpendicular to the rotating shaft 24, from the reducer side refrigerant flow path 25 to the motor side refrigerant flow path 15, so that the refrigerant flow path can be adjacent to the oil catch tank 32.

[0058] In this embodiment, the oil catch tank 32 extends in an arc shape centered on the rotating shaft 24, and the refrigerant inlet 26 is located at the top of the reducer housing 21. The partition wall refrigerant flow path 31 is formed so that the refrigerant flows inside the partition wall 19 in a direction perpendicular to the rotating shaft 24. The oil catch tank 32 and the partition wall refrigerant flow path 31 are located at positions overlapping in the direction of the rotating shaft 24. The circumferential length of the partition wall refrigerant flow path 31 is configured to be greater than the circumferential length of the oil catch tank 32.

[0059] In this configuration, the partition wall refrigerant flow path 31 and the oil catch tank 32 are configured to overlap in the direction of the rotation axis at the partition wall 19, so that the lubricating oil temporarily stored in the oil catch tank 32 can sufficiently exchange heat with the refrigerant flowing through the adjacent partition wall refrigerant flow path 31 in a direction perpendicular to the rotation axis 24, via the partition wall 19.

[0060] In addition, in this embodiment, the oil catch tank 32 is positioned above the rotating shaft 24, so that the high-temperature lubricating oil scooped up by the reducer 20 exchanges heat with the refrigerant in the reducer side refrigerant flow path 25 around the reducer housing 21, and also with the refrigerant in the partition wall refrigerant flow path 31 via the partition wall 19, thereby increasing the opportunities for heat exchange between the lubricating oil and the refrigerant and enabling the lubricating oil to be cooled more effectively.

[0061] In this embodiment, the reducer side refrigerant flow passage 25 is formed in the reducer housing 21 so as to communicate in the circumferential direction from above the rotating shaft 24 to the reservoir portion.

[0062] In this configuration, since the reducer side refrigerant flow path 25 extends to the oil pan 210 in the reducer housing 21, heat exchange occurs between the refrigerant and the lubricating oil stored in the oil pan 210. In particular, when warming up is required, such as during a cold start of the vehicle, the refrigerant with the highest temperature before heat exchange flows, and therefore, heat exchange occurs between the lubricating oil stored in the oil pan 210 and this refrigerant, allowing the lubricating oil to be sufficiently warmed up.

[0063] In addition, in this embodiment, the reducer housing 21 is composed of an inner tube 211 and an outer tube 212, and a groove portion 211a is formed in the inner tube 211. The groove portion 211a of the inner tube 211 and the inner surface of the outer tube 212 form a reducer side refrigerant flow path 25.

[0064] In this configuration, the reducer side refrigerant flow path 25 can be formed by the groove portion 211a of the inner tube 211 and the outer tube 212, so that the refrigerant flow path can be easily formed, for example, by forming the inner tube 211 and the outer tube 212 by casting.

[0065] In addition, in this embodiment, the reducer side refrigerant flow path 25 extends from the top to the bottom of the reducer housing 21, then turns back from the bottom to the top, and then connects to the motor side refrigerant flow path 15, so that the time for heat exchange between the reduction mechanism 22 and the lubricating oil and the refrigerant is longer, improving the heat exchange efficiency.

[0066] In addition, this embodiment is equipped with a reduction mechanism 22 constituted by a planetary gear mechanism, and the reduction gear housing 21 and the motor housing 11 are separated by a partition wall 19 formed in a direction perpendicular to the rotation shaft 24. The reduction gear 20 side of the partition wall 19 is equipped with an oil catch tank 32 for temporarily storing lubricating oil scooped up by the gears of the reduction gear mechanism 22. The partition wall 19 connects the reduction gear side refrigerant flow path 25 and the motor side refrigerant flow path 15, and has a partition wall refrigerant flow path 31 formed to allow refrigerant to flow at a position adjacent to the oil catch tank 32 and the oil pan 210.

[0067] In this configuration, the reduction mechanism 22 of the reducer 20 is configured as a planetary gear mechanism, and is configured to enable a large reduction ratio on a single shaft. A large reduction ratio results in a large amount of heat generated by the reduction mechanism 22, but the lubricating oil exchanges heat with the lowest temperature refrigerant flowing in from the refrigerant inlet 26 on the reducer 20 side, and further exchanges heat with the refrigerant in the oil catch tank 32, making it possible to appropriately cool the lubricating oil.

[0068] The above-described embodiments of the present invention, the above-described embodiments, and the modified examples are merely examples of application of the present invention, and are not intended to limit the technical scope of the present invention to the specific configurations of the above-described embodiments.

[0069] In the above embodiment, the drive device 1 has been described as having a configuration in which the reducer 20 and the motor 10 are connected to one shaft, but the configuration is not limited to this. The reducer 20 may be configured as a reduction mechanism having two or three shafts. [Explanation of symbols]

[0070] 1: drive unit, 10: motor, 11: motor housing, 15: motor side refrigerant flow path, 19: partition wall, 20: reducer, 21: reducer housing, 22: reduction mechanism, 23: differential gear, 24: rotating shaft, 25: reducer side refrigerant flow path, 25a: communication passage, 26: refrigerant inlet, 27: refrigerant outlet, 31: partition wall refrigerant flow path, 32: oil catch tank, 100: cooling circuit, 110: motor chamber, 111: inner cylinder, 111a: groove, 112: outer cylinder, 200: reducer chamber, 210: oil pan, 211: inner cylinder, 211a: groove, 211b: first groove, 211c: second groove, 212: outer cylinder

Claims

1. A drive device comprising a motor housed in a motor housing, and a transmission housed in a transmission housing for changing the speed of rotation of the motor and outputting the rotation, the transmission housing and the motor housing being integrally connected in a rotation axis direction, The transmission housing has a coolant inlet and a first coolant flow path formed around the transmission including a bottom of the transmission housing, the motor housing has a second refrigerant passage that is in communication with the first refrigerant passage and is formed around the motor; A reservoir for storing lubricating oil for lubricating the transmission is formed at the bottom of the transmission housing. Drive unit.

2. 2. The drive device according to claim 1, the transmission housing and the motor housing are partitioned by a partition wall formed in a direction perpendicular to the rotation shaft, An oil catch tank is formed on the transmission side of the partition wall to temporarily store lubricating oil scooped up by the gears of the transmission, The partition wall has a third refrigerant flow path that communicates with the first refrigerant flow path and the second refrigerant flow path and is formed so that the refrigerant flows at a position adjacent to the oil catch tank and the storage portion. Drive unit.

3. 3. The drive device according to claim 2, The transmission housing and the motor housing are formed in a cylindrical shape, and the outer shape of the transmission housing is larger than the outer shape of the motor housing, The third refrigerant flow path is configured to extend in a direction perpendicular to the rotation axis. Drive unit.

4. 4. The drive device according to claim 3, The oil catch tank is formed in an arc shape centered on the rotation axis, the coolant inlet is disposed in an upper portion of the transmission housing; the third refrigerant flow path is formed so that a refrigerant flows through the partition wall in a direction perpendicular to the rotation axis, the oil catch tank and the third refrigerant flow path are disposed in a position overlapping with each other in the direction of the rotation axis, The circumferential length of the third refrigerant flow path is configured to be greater than the circumferential length of the oil catch tank. Drive unit.

5. 5. The drive device according to claim 4, The oil catch tank is disposed above the rotation shaft. Drive unit.

6. 5. The drive device according to claim 4, The first refrigerant flow path is formed in the transmission housing so as to communicate in a circumferential direction from a position above the rotating shaft to the storage portion. Drive unit.

7. 5. The drive device according to claim 4, The transmission housing is composed of an inner cylinder and an outer cylinder, A groove is formed in the inner cylinder, The groove portion of the inner cylinder and the inner circumferential surface of the outer cylinder form the first refrigerant flow path. Drive unit.

8. 7. The drive device according to claim 6, The first refrigerant flow path extends from the top to the bottom of the transmission housing, then turns back from the bottom to the top, and then connects to the second refrigerant flow path. Drive unit.

9. 2. The drive device according to claim 1, the transmission is a reducer configured with a planetary gear mechanism, the transmission housing and the motor housing are defined by a partition wall formed in a direction intersecting the rotation shaft, a catch tank for temporarily storing lubricating oil scooped up by the gears of the transmission on the transmission side of the partition wall; the partition wall has a third refrigerant flow path that communicates the first refrigerant flow path and the second refrigerant flow path and is formed so that the refrigerant flows at a position adjacent to the catch tank and the storage portion. Drive unit.

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