Drive device for vehicle

Abstract

The drive device includes a first motor, a first gear mechanism, a second motor, a second gear mechanism, and a housing. The housing has a first gear chamber that accommodates the first gear mechanism, a second gear chamber that accommodates the second gear mechanism, and a partition wall that is interposed between the first gear chamber and the second gear chamber. The first gear chamber and the second gear chamber are arranged in the left-right direction of the vehicle with a partition wall therebetween. The partition wall is provided with a first communication path through which the lubricating liquid retained in the lower part of the first gear chamber flows to the second gear chamber, and a second communication path through which the lubricating liquid retained in the lower part of the second gear chamber flows to the first gear chamber, the first communication path and the second communication path being independent from each other.

Description

Technical Field

[0001] The technology disclosed in this specification relates to a drive device for a vehicle. Background Art

[0002] Japanese Patent Application Laid-Open No. 2016-205444 describes a vehicle drive device. The drive device drives left and right wheels independently by two motors. A housing of the drive device has two gear chambers, and the two gear chambers are arranged in the left-right direction of the vehicle with a partition wall therebetween.

[0003] In a vehicle drive device, there is a problem that the lubricating fluid in the gear chamber becomes unbalanced due to centrifugal force when the vehicle turns. In particular, in the drive device as described above, the lubricating fluid moves toward the partition wall in one gear chamber, while the lubricating fluid moves away from the partition wall in the other gear chamber. As a result, in the other gear chamber, there is a possibility that the lubricating fluid is insufficient for the bearings and gears located near the partition wall. Summary of the invention

[0004] This specification provides a technology for sufficiently lubricating the vicinity of a partition wall in a drive device having two gear chambers even when a vehicle turns.

[0005] The technology disclosed in this specification is embodied as a drive device for a vehicle. As this embodiment, the drive device includes:

[0006] a first motor, the first motor being used to drive a right wheel of the vehicle;

[0007] a first gear mechanism, the first gear mechanism being sandwiched between the first motor and the right wheel;

[0008] a second motor, the second motor being used to drive a left wheel of the vehicle;

[0009] a second gear mechanism, the second gear mechanism being interposed between the second motor and the left wheel; and

[0010] a housing that accommodates the first gear mechanism and the second gear mechanism together with the lubricating fluid,

[0011] The housing has a first gear chamber for accommodating a first gear mechanism, a second gear chamber for accommodating a second gear mechanism, and a partition wall interposed between the first gear chamber and the second gear chamber.

[0012] The first gear chamber and the second gear chamber are arranged in the left-right direction of the vehicle with a partition wall between them.

[0013] The partition wall is provided with a first communication passage for flowing the lubricating fluid accumulated in the lower portion of the first gear chamber to the second gear chamber and a second communication passage for flowing the lubricating fluid accumulated in the lower portion of the second gear chamber to the first gear chamber independently of each other.

[0014] Based on the above structure, even when the vehicle turns in any direction, the vicinity of the partition wall can be reliably lubricated. For example, the vehicle turns to the right. In this case, in the first gear chamber, the lubricating fluid moves toward the partition wall, while in the second gear chamber, the lubricating fluid moves away from the partition wall. As a result, in the second gear chamber, the liquid level of the lubricating fluid becomes low near the partition wall, but the lubricating fluid concentrated at the partition wall in the first gear chamber is supplied to the second gear chamber through the first connecting passage provided in the partition wall. Similarly, when the vehicle turns to the left, the lubricating fluid passage concentrated at the partition wall in the second gear chamber is provided in the second connecting passage of the partition wall and supplied to the first gear chamber. Therefore, even when the vehicle turns in any direction, the vicinity of the partition wall can be reliably lubricated.

[0015] In the above embodiment, the first communication passage may include a first inlet opening in the first gear chamber and a first outlet opening in the second gear chamber, and the first inlet may be located above the first outlet.

[0016] Similarly, the second communication passage may include a second inlet opening in the second gear chamber and a second outlet opening in the first gear chamber, and the second inlet may be located above the second outlet.

[0017] With this structure, the lubricating fluid is smoothly supplied from the first gear chamber to the second gear chamber or from the second gear chamber to the first gear chamber not only by the action of the centrifugal force but also by the difference in fluid level of the lubricating fluid on both sides of the partition wall.

[0018] In the above embodiment, the first communication passage may be inclined downward from the first inlet toward the first outlet.

[0019] Similarly, the second communication passage may be inclined downward from the second inlet toward the second outlet.

[0020] According to this structure, the lubricating fluid is also supplied more smoothly from the first gear chamber to the second gear chamber or from the second gear chamber to the first gear chamber by utilizing the gravity acting on the lubricating fluid.

[0021] In the above embodiment, a first bearing holding portion for holding a bearing of the first gear mechanism may be provided in the partition wall of the first gear chamber. In this case, the second outlet of the second communication passage may be located in the first bearing holding portion.

[0022] Similarly, in the second gear chamber, a second bearing holding portion for holding a bearing of the second gear mechanism may be provided on the partition wall. In this case, the first outlet of the first communication passage may be located at the second bearing holding portion.

[0023] With this structure, the bearing held by the partition wall can be lubricated more reliably.

[0024] In the above-described embodiment, the first bearing holding portion and the second bearing holding portion may be coaxially located with a partition wall interposed therebetween.

[0025] However, as another embodiment, the first bearing holding portion and the second bearing holding portion may be located at positions separated from each other. In this case, the first communication passage and the second communication passage may also be provided at positions separated from each other according to the positions of the bearing holding portions. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Features, advantages, and technical and industrial significance of embodiments of the present invention will be described below with reference to the accompanying drawings, in which like reference numerals represent like elements, and wherein:

[0027] Figure 1 The structure of the driving device 10 according to the embodiment is schematically shown.

[0028] Figure 2 Enlarge Figure 1 Part II of .

[0029] Figure 3 yes Figure 2 Cross-sectional view along line III-III.

[0030] Figure 4 The behavior of the lubricating fluid LB when the vehicle 2 turns right is shown. DETAILED DESCRIPTION

[0031] The drive device 10 of the embodiment will be described with reference to the accompanying drawings. The drive device 10 is a drive device for a vehicle 2. The vehicle 2 is an electric vehicle (electrified vehicle). The electric vehicle mentioned here refers to, for example, a battery electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, and a fuel cell electric vehicle. The drive device 10 is mounted on the vehicle 2 and drives the right wheel 4 and the left wheel 6 of the vehicle 2. The right wheel 4 and the left wheel 6 are arranged on the same axis. In addition, the right wheel 4 and the left wheel 6 can be the front wheels of the vehicle 2 or the rear wheels of the vehicle 2.

[0032] In the drawings, direction UP indicates the upper direction of the up-down direction of the vehicle 2, and direction DW indicates the lower direction of the up-down direction. Direction RH indicates the right direction of the left-right direction of the vehicle 2, and direction LH indicates the left direction of the left-right direction. Furthermore, direction FR indicates the front direction of the front-back direction of the vehicle 2, and direction RR indicates the rear direction of the front-back direction.

[0033] like Figure 1 to Figure 3 As shown, the drive device 10 includes a first motor 12, a first gear mechanism 14, a second motor 16, and a second gear mechanism 18. The first motor 12 is a prime mover for driving the right wheel 4 of the vehicle 2. The first motor 12 is connected to the right wheel 4 via the first gear mechanism 14. The second motor 16 is a prime mover for driving the left wheel 6 of the vehicle 2. The second motor 16 is connected to the left wheel 6 via the second gear mechanism 18. The drive device 10 is configured to independently drive the right wheel 4 and the left wheel 6 by the two motors 12 and 16.

[0034] The first gear mechanism 14 is clamped between the first motor 12 and the right wheel 4. The first gear mechanism 14 includes a plurality of gears 14g, a plurality of rotating shafts 14s, and a plurality of bearings 14b. The plurality of gears 14g are engaged in a series to transmit torque between the first motor 12 and the right wheel 4. Each rotating shaft 14s can hold at least one gear 14g and is supported to rotate by more than two bearings 14b. Although not particularly limited, the first gear mechanism 14 can also be configured as follows: in the reducer, the torque output by the first motor 12 is amplified and transmitted to the right wheel 4.

[0035] The second gear mechanism 18 is sandwiched between the second motor 16 and the left wheel 6. The second gear mechanism 18 includes a plurality of gears 18g, a plurality of rotating shafts 18s, and a plurality of bearings 18b. The plurality of gears 18g are engaged in series to transmit torque between the second motor 16 and the left wheel 6. Each rotating shaft 18s holds at least one gear 18g and is supported to rotate by two or more bearings 18b. The second gear mechanism 18 can also be configured such that the torque output by the second motor 16 is amplified in the reducer and transmitted to the left wheel 6.

[0036] The drive device 10 also includes a housing 20. The housing 20 accommodates the first motor 12, the first gear mechanism 14, the second motor 16, and the second gear mechanism 18 together with the lubricating liquid LB. The lubricating liquid LB may be, for example, oil. The housing 20 includes a first gear chamber 22, a second gear chamber 24, and a partition wall 26. The first gear chamber 22 accommodates the first gear mechanism 14, and the second gear chamber 24 accommodates the second gear mechanism 18. The lubricating liquid LB is retained in the lower part of the first gear chamber 22 and the second gear chamber 24. The lubricating liquid LB is supplied to various locations in the housing 20 by the rotation of the gears 14g and 18g and an oil pump (not shown).

[0037] The partition wall 26 is interposed between the first gear chamber 22 and the second gear chamber 24. The first gear chamber 22 and the second gear chamber 24 are arranged in the left-right direction across the partition wall 26. Figure 2 , Figure 3 As shown, a first communication passage 30 and a second communication passage 32 are provided in the partition wall 26. The first communication passage 30 has a first inlet 30a opened in the first gear chamber 22, and a first outlet 30b opened in the second gear chamber 24, and extends from the first inlet 30a to the first outlet 30b. On the other hand, the second communication passage 32 has a second inlet 32a opened in the second gear chamber 24, and a second outlet 32b opened in the first gear chamber 22, and extends from the second inlet 32a to the second outlet 32b. Here, the first communication passage 30 and the second communication passage 32 are independent of each other and are not connected to each other at the partition wall 26.

[0038] Based on the above structure, even when the vehicle 2 turns in any direction, the vicinity of the partition wall 26 can be reliably lubricated. For example, the vehicle 2 turns to the right RH. In this case, Figure 4 As shown, in the first gear chamber 22, the lubricating liquid LB moves toward the partition wall 26, whereas in the second gear chamber 24, the lubricating liquid LB moves away from the partition wall 26. As a result, in the second gear chamber 24, the liquid level of the lubricating liquid LB becomes low near the partition wall 26. However, the lubricating liquid LB concentrated at the partition wall 26 in the first gear chamber 22 is supplied to the second gear chamber 24 through the first connecting passage 30 provided at the partition wall 26 (see arrow F). Similarly, when the vehicle 2 turns to the left LH, the lubricating liquid LB concentrated at the partition wall 26 in the second gear chamber 24 is supplied to the first gear chamber 22 through the second connecting passage 32 provided at the partition wall 26. Therefore, even when the vehicle 2 turns in either direction, the vicinity of the partition wall 26 can be reliably lubricated.

[0039] Although not particularly limited, the first inlet 30a may be located above the first outlet 30b. Furthermore, the first communicating passage 30 may be inclined downward from the first inlet 30a toward the first outlet 30b. Similarly, the second inlet 32a may be located above the second outlet 32b. Furthermore, the second communicating passage 32 may be inclined downward from the second inlet 32a toward the second outlet 32b. Based on this structure, the lubricating liquid LB can be smoothly supplied from the first gear chamber 22 to the second gear chamber 24 or from the second gear chamber 24 to the first gear chamber 22 not only according to the centrifugal force acting on the lubricating liquid LB, but also according to the liquid level difference of the lubricating liquid LB on both sides of the partition wall 26.

[0040] However, as another embodiment, the first inlet 30a and the first outlet 30b may be located at the same position in the vertical direction and the first communication path 30 may extend in the horizontal direction. Even in this case, when the vehicle 2 turns right, the lubricating fluid LB is supplied from the first gear chamber 22 to the second gear chamber 24 through the first communication path 30 by the centrifugal force acting on the lubricating fluid LB. Similarly, even if the second communication path 32 extends in the horizontal direction, when the vehicle 2 turns left, the lubricating fluid LB is supplied from the second gear chamber 24 to the first gear chamber 22 through the second communication path 32.

[0041] Although not particularly limited, in the drive device 10 of the present embodiment, in the first gear chamber 22, the second outlet 32b of the second communication passage 32 is located at the first bearing holding portion 40. The first bearing holding portion 40 is provided on the partition wall 26, and holds the bearing 14b of the first gear mechanism 14. Specifically, the first bearing holding portion 40 has a recessed portion 40a for the bearing 14b to be embedded, and the second outlet 32b of the second communication passage 32 opens in the recessed portion 40a. Based on this structure, the bearing 14b of the first gear mechanism 14 held by the partition wall 26 can be lubricated more reliably.

[0042] Similarly, in the second gear chamber 24, the first outlet 30b of the first communicating passage 30 is located at the second bearing retaining portion 42. The second bearing retaining portion 42 is provided on the partition wall 26 to retain the bearing 18b of the second gear mechanism 18. In detail, the second bearing retaining portion 42 has a recessed portion 42a for the bearing 18b to be embedded, and the first outlet 30b of the first communicating passage 30 opens in the recessed portion 42a. Based on this structure, the bearing 18b of the second gear mechanism 18 retained by the partition wall 26 can be lubricated more reliably. In addition, the second bearing retaining portion 42 is located at a coaxial position with the first bearing retaining portion 40 across the partition wall 26.

[0043] The embodiments of the present technology are described in detail above, but they are only examples and do not limit the scope of the claims. The technologies described in the claims include technologies that make various deformations and changes to the specific examples illustrated above. The technical elements described in this specification or the drawings exert the usefulness of the technology alone or through various combinations, and are not limited to the combinations described in the claims at the time of application. In addition, the technologies illustrated in this specification or the drawings are technologies that achieve multiple purposes at the same time, and achieving one of the purposes itself has technical usefulness.

Claims

1. A driving device for a vehicle, wherein: have: a first motor, the first motor being used to drive a right wheel of the vehicle; a first gear mechanism, the first gear mechanism being interposed between the first motor and the right wheel; a second motor, the second motor being used to drive a left wheel of the vehicle; a second gear mechanism interposed between the second motor and the left wheel; and a housing that accommodates the first gear mechanism and the second gear mechanism together with a lubricating fluid, The housing includes a first gear chamber for accommodating the first gear mechanism, a second gear chamber for accommodating the second gear mechanism, and a partition wall interposed between the first gear chamber and the second gear chamber. The first gear chamber and the second gear chamber are arranged in a left-right direction of the vehicle with the partition wall interposed therebetween. The partition wall is provided with a first communication passage for flowing the lubricating fluid accumulated in the lower portion of the first gear chamber to the second gear chamber and a second communication passage for flowing the lubricating fluid accumulated in the lower portion of the second gear chamber to the first gear chamber independently of each other.

2. The driving device according to claim 1, wherein: The first communication passage includes a first inlet opening in the first gear chamber and a first outlet opening in the second gear chamber, wherein the first inlet is located above the first outlet. The second communication passage includes a second inlet opening in the second gear chamber and a second outlet opening in the first gear chamber, wherein the second inlet is located above the second outlet.

3. The driving device according to claim 2, wherein: The first communication passage is inclined downward from the first inlet toward the first outlet. The second communication passage is inclined downward from the second inlet toward the second outlet.

4. The driving device according to claim 2 or 3, wherein: In the first gear chamber, a first bearing holding portion for holding a bearing of the first gear mechanism is provided on the partition wall, and the second outlet of the second communication passage is located at the first bearing holding portion. In the second gear chamber, a second bearing holding portion that holds a bearing of the second gear mechanism is provided on the partition wall, and the first outlet of the first communication passage is located at the second bearing holding portion.

5. The driving device according to claim 4, wherein: The first bearing holding portion and the second bearing holding portion are coaxially located with the partition wall interposed therebetween.

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