Vehicle drive unit

Abstract

A rotary electric machine and a gear mechanism are accommodated in a case which comprises a first accommodation chamber (1) and a second accommodation chamber (2) that are partitioned by a partition wall part (4). The gear mechanism supplies an oil to a lubrication target part by scraping up the oil in the case. An opening (5) through which the first accommodation chamber (1) and the second accommodation chamber (2) are in communication with each other is formed in the partition wall part (4). A valve element (6) is attached at the opening (5) so as to allow flow of the oil from the first accommodation chamber (1) to the second accommodation chamber (2) and restrict flow of the oil from the second accommodation chamber (2) to the first accommodation chamber (1).

Description

[Technical Field]

[0001] The present invention relates to a vehicle drive device that includes a case that houses a rotating electric machine that is a source of drive power for wheels and a gear mechanism. [Background technology]

[0002] Japanese Patent Application Laid-Open Publication No. 2020-156296 discloses a vehicle drive device (1) in which a case (1) housing a rotating electric machine (2) and gear mechanisms (4, 5) contains oil for lubricating (including cooling) these components (reference numerals in parentheses in the Background Art section refer to the referenced document). The oil is stored in an oil reservoir (P) within the case (6). Some of the gears of the gear mechanisms (4, 5) scoop up the oil stored in the oil reservoir (P), and the oil is supplied to bearings and the stator core (32) of the rotating electric machine (2) via a catch tank and oil passages formed within the case (6). The interior space of the case (6) is divided by a partition wall (61c) into a first housing chamber (81) housing the rotating electric machine and a second housing chamber (82) housing the gear mechanism. The partition wall (61c) has an opening (68) that connects the first storage chamber (81) and the second storage chamber (82) to each other. Oil can flow between the first storage chamber (81) and the second storage chamber (82) through the opening (68). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2020-156296 Summary of the Invention [Problem to be solved by the invention]

[0004] As described above, if oil is allowed to flow between the two storage chambers, the oil may be concentrated in one of the storage chambers due to inertial forces caused by tilting of the vehicle or by turning or accelerating the vehicle. For example, if oil is concentrated toward the first storage chamber (81) and the amount of oil in the second storage chamber (82) decreases, the oil scooped up by the gears may decrease, and the oil supply via the catch tank or oil passage may become insufficient. Furthermore, if an oil pump is housed in the first storage chamber (81), if oil is concentrated toward the second storage chamber (82) and the amount of oil in the first storage chamber (81) decreases, the oil pump may not be able to sufficiently draw oil. On the other hand, if the oil flow between the two storage chambers is blocked and the oil is stored independently in each storage chamber, a drain hole would be required for each storage chamber when changing the oil, which may complicate the structure of the case.

[0005] In view of the above background, it is desirable to provide a vehicle drive device that prevents oil from concentrating in any one of a plurality of housing chambers formed in a case. [Means for solving the problem]

[0006] In consideration of the above-mentioned problems, a vehicle drive device is a vehicle drive device comprising: a rotating electric machine that is a driving force source for a wheel; an output member that is drivingly connected to the wheel; a gear mechanism that drivingly connects the rotating electric machine and the output member; and a case that houses the rotating electric machine and the gear mechanism, wherein the case is partitioned by a partition wall portion of the case and comprises a first storage chamber that houses the rotating electric machine and a second storage chamber that houses the gear mechanism, the gear mechanism supplies oil to a part to be lubricated by scooping up oil inside the case, an opening that connects the first storage chamber and the second storage chamber is formed in the partition wall portion, and a valve body is attached to the opening to allow oil to flow from the first storage chamber to the second storage chamber and to regulate the flow of oil from the second storage chamber to the first storage chamber.

[0007] According to this configuration, a partition wall separating the first and second housing chambers has an opening that connects the first and second housing chambers. A valve body is attached to this opening to allow oil to flow from the first housing chamber to the second housing chamber and to restrict oil flow from the second housing chamber to the first housing chamber. Therefore, even if the oil level tilts due to inertial forces caused by vehicle tilt, turning, or acceleration / deceleration, the oil level in the second housing chamber can be prevented from dropping. That is, even if the oil level tilts, the gear mechanism housed in the second housing chamber can scoop up the oil inside the case, thereby supplying the oil to the lubrication target area. Thus, this configuration provides a vehicle drive device that prevents oil from concentrating in any one of the multiple housing chambers formed in the case.

[0008] Further features and advantages of the vehicle drive device will become apparent from the following description of exemplary, non-limiting embodiments which are given with reference to the drawings. [Brief explanation of the drawings]

[0009] [Figure 1] axial cross-sectional view of a vehicle drive device [Figure 2] Skeleton diagram of a vehicle drive system [Figure 3] A plan view of the case body as seen from the side of the second storage chamber. [Figure 4] FIG. 1 is a perspective view showing an example of a valve body; [Figure 5] A partial cross-sectional view of a partition wall showing the relationship between the opening and the valve body. [Figure 6] FIG. 10 is a diagram showing an example of the state of oil in a case when a vehicle drive device having a valve body in an opening is tilted. [Figure 7] FIG. 10 is a diagram showing an example of the state of oil in a case when a vehicle drive device that does not have a valve body in an opening is tilted; [Figure 8] A plan view of the case body as seen from the first storage chamber side. [Figure 9] FIG. 1 is an axial cross-sectional view showing an example of a drain hole and a communication hole; DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. As shown in FIGS. 1 and 2, a vehicle drive device 100 according to this embodiment includes a rotating electric machine MG that serves as a driving force source for a wheel W, an output member OUT drivingly connected to the wheel W, a gear mechanism TA that drivingly connects the rotating electric machine MG and the output member OUT, and a case 10 that houses the rotating electric machine MG and the gear mechanism TA. As shown in FIG. 1, the case 10 includes at least a first housing chamber 1 and a second housing chamber 2 that are partitioned by a partition wall 4 of the case 10. As will be described later, in this embodiment, the rotating electric machine MG is housed in the first housing chamber 1, and the gear mechanism TA is housed in the second housing chamber 2. In addition, in this embodiment, the case 10 also includes a third housing chamber 3 that is partitioned from the first housing chamber 1 and the second housing chamber 2 by a peripheral wall 11a. The third housing chamber 3 houses an inverter INV that drives and controls the rotating electric machine MG.

[0011] As shown in FIGS. 1 and 2, the rotating electric machine MG is disposed on a first axis A1, and the output member OUT is disposed on a second axis A2 that is parallel to the first axis A1. The gear mechanism TA is provided in a power transmission path between the rotating electric machine MG and the output member OUT and includes a plurality of gears G that drive-couple the rotating electric machine MG and the output member OUT. The gears G also include gears G that constitute a counter gear mechanism CG, which will be described later. The counter gear mechanism CG is disposed on a third axis A3 that is parallel to the first axis A1 and the second axis A2. The gear mechanism TA also includes a differential gear mechanism DF that distributes driving force transmitted from the rotating electric machine MG via the plurality of gears G to a pair of wheels W. As will be described in detail later, a pair of output gears (side gears SG) of this differential gear mechanism DF corresponds to the output member OUT. In this embodiment, the wheels W and the output member OUT are coupled via an output shaft DS. This output shaft DS can also be considered as the output member OUT. Furthermore, the pair of side gears SG of the differential gear mechanism DF correspond to the output member OUT and can also be considered to be included in the gear mechanism TA.

[0012] In this application, the term "driving connection" refers to a state in which two rotating elements are connected so as to be able to transmit a driving force, and includes a state in which the two rotating elements are connected so as to rotate integrally, or a state in which the two rotating elements are connected so as to be able to transmit a driving force via one or more transmission members. Such transmission members include various members that transmit rotation at the same speed or at a variable speed, such as a shaft, a gear mechanism, a belt, a chain, etc. The transmission members may also include an engagement device that selectively transmits rotation and driving force, such as a friction engagement device or a meshing engagement device.

[0013] As will be described in detail later, as shown in Fig. 1, an input gear G1 is connected to the rotor Rt of the rotating electrical machine MG so as to rotate integrally with the rotor Rt. In this embodiment, the input gear G1 is formed integrally with the input shaft IS on the outer circumferential side of the input shaft IS, which is connected to the rotor shaft RS of the rotor Rt so as to rotate integrally with the rotor shaft RS. The input gear G1 is also included in the multiple gears G that constitute the gear mechanism TA.

[0014] The first axis A1, the second axis A2, and the third axis A3 are different virtual axes and are arranged parallel to one another as described above. In the following description, the direction parallel to the first axis A1 is referred to as the axial direction L. Since the first axis A1 and the second axis A2 are parallel to one another, the axial direction L is also parallel to the second axis A2. Furthermore, since the third axis A3 is also parallel to the first axis A1 and the second axis A2, the axial direction L is also parallel to the third axis A3. One side of the axial direction L (in this embodiment, the side where the rotating electric machine MG is arranged with respect to the gear mechanism TA) is referred to as the "axial first side L1," and the opposite side is referred to as the "axial second side L2."

[0015] Furthermore, a direction perpendicular to each of the first axis A1, the second axis A2, and the third axis A3 is referred to as a "radial direction R" based on each axis. When it is not necessary to distinguish which axis is used as a reference or when it is clear which axis is used as a reference, the direction may simply be referred to as a "radial direction R." Furthermore, a direction along the vertical direction when the vehicle drive device 100 is attached to a vehicle is referred to as an "up-down direction V." Furthermore, in this embodiment, one side of the up-down direction V, that is, a first up-down side V1, is the upper side, and the other side, that is, a second up-down side V2, is the lower side. When the vehicle drive device 100 is attached to a vehicle in a state parallel to a horizontal plane, one direction of the radial direction R and the up-down direction V coincide.

[0016] Furthermore, the direction perpendicular to the axial direction L and the up-down direction V is referred to as the "width direction H." One side of the width direction H is referred to as the first width direction side H1, and the other side is referred to as the second width direction side H2. As with the up-down direction V, one direction of the radial direction R coincides with the width direction H. In the following description, terms relating to the direction, position, etc. of each component are concepts that also include differences due to tolerances that may be tolerated in manufacturing. Furthermore, the directions of each component represent the directions when they are assembled to the vehicle drive device 100. In this embodiment, the width direction H corresponds to the front-to-rear direction of the vehicle when the vehicle drive device 100 is attached to the vehicle.

[0017] In this embodiment, the case 10 includes a case main body 11 integrally molded to form the first storage chamber 1, the second storage chamber 2, and the third storage chamber 3. Here, "integrally molded" refers to a unitary member formed from a common material, for example, as a single die casting. Naturally, the case main body 11 may be composed of multiple components. In addition to the case main body 11, the case 10 also includes a first cover 10a joined to the case main body 11 from the first axial side L1, a second cover 10b joined to the case main body 11 from the second axial side L2, and a third cover 10c joined to the case main body 11 from the first vertical side V1. The third storage chamber 3 is formed as a space partitioned from the first storage chamber 1 and the second storage chamber 2, generally closer to the second axial side L2 than the first storage chamber 1 and on the first vertical side V1 than the second storage chamber 2.

[0018] A partition wall 4 is formed inside the case 10, specifically the cylindrical case main body 11, extending in the vertical direction V and the width direction H and separating the first storage chamber 1 and the second storage chamber 2 (see FIGS. 1, 3, 8, etc.). The partition wall 4 separates the first storage chamber 1 and the second storage chamber 2 in the axial direction L. The first storage chamber 1 is formed as a space surrounded by the case main body 11, the first cover 10a, and the partition wall 4. The second storage chamber 2 is formed as a space surrounded by the case main body 11, the second cover 10b, and the partition wall 4. The third storage chamber 3 is formed as a space surrounded by a peripheral wall 11a on the first side V1 in the vertical direction of the cylindrical case main body 11, a side wall 11b erected from the peripheral wall 11a toward the first side V1 in the vertical direction, and the third cover 10c.

[0019] The rotating electric machine MG is a rotating electric machine (motor / generator) that operates on multi-phase AC (e.g., three-phase AC) and can function as both an electric motor and a generator. The rotating electric machine MG receives power from a DC power source (not shown) for power running, or generates power using the inertial force of the vehicle and supplies it to the DC power source (regenerates power). As shown in FIG. 1 , the rotating electric machine MG has a stator St fixed to a case 10 and a rotor Rt rotatably supported inside the stator St in the radial direction R. The stator St includes a stator core and a stator coil Sc wound around the stator core, and the rotor Rt includes a rotor core and a permanent magnet arranged in the rotor core.

[0020] The rotor Rt of the rotating electric machine MG is connected to a rotor shaft RS, which is connected to an input shaft IS. An input gear G1 is integrally formed on the input shaft IS on the radially outer side of the input shaft IS. Of course, the input gear G1 may be formed as a separate member from the input shaft IS and connected to the input shaft IS. That is, the rotor Rt is drivingly connected to the input gear G1 via the rotor shaft RS and the input shaft IS, and the input gear G1 rotates integrally with the rotor Rt. As described below, the input gear G1 is drivingly connected to a counter gear mechanism CG. The rotor shaft RS is rotatably supported relative to the case 10 by a pair of first bearings B1, and the input shaft IS is rotatably supported relative to the case 10 by a pair of second bearings B2. The pair of first bearings B1 are supported by the first cover 10a and the partition wall 4, respectively. The pair of second bearings B2 are supported by the partition wall 4 and the second cover 10b, respectively.

[0021] The counter gear mechanism CG is disposed on a third axis A3 parallel to the first axis A1 and the second axis A2, and drivingly couples the rotary electric machine MG and the differential gear mechanism DF via an input gear G1. In this embodiment, the counter gear mechanism CG has two gears (a first counter gear G2 and a second counter gear G3) coupled by a shaft member (a counter shaft CS). That is, the counter gear mechanism CG is disposed on the third axis A3 and includes a first counter gear G2 meshing with the input gear G1, and a second counter gear G3 that rotates integrally with the first counter gear G2 and meshes with a differential input gear G4 of the differential gear mechanism DF (described later). The counter shaft CS is rotatably supported relative to the case 10 by a pair of third bearings B3. The third bearings B3 are supported by the partition wall 4 and the second cover 10b, respectively.

[0022] The differential gear mechanism DF includes a differential case DC, a pair of pinion gears PG, and a pair of side gears SG. The pair of pinion gears PG and the pair of side gears SG are all bevel gears, and the differential gear mechanism DF of this embodiment is a bevel gear type differential gear mechanism. Naturally, the differential gear mechanism DF may have a different configuration, for example, a planetary gear type differential gear mechanism. The differential case DC is a hollow member that houses the pair of pinion gears PG and the pair of side gears SG. In this embodiment, the differential case DC is rotatably supported relative to the case 10 by a pair of fourth bearings B4. In this embodiment, the pair of fourth bearings B4 are supported by the partition wall portion 4 and the second cover 10b, respectively.

[0023] The differential case DC and the differential input gear G4 are connected to rotate integrally. The pair of pinion gears PG are arranged to face each other at a distance in the radial direction R based on the second axis A2. The differential case DC supports the pinion shaft PS so as to rotate integrally with the differential case DC, and the pair of pinion gears PG are attached to the pinion shaft PS. Each of the pair of pinion gears PG can rotate (spin) about the pinion shaft PS and can also rotate (revolve) about the second axis A2. A pair of side gears SG mesh with the pair of pinion gears PG. The pair of side gears SG are arranged to face each other across the pinion shaft PS at a distance in the axial direction L so as to rotate about the second axis A2 as the rotation axis.

[0024] Each side gear SG is drivingly connected to a pair of output shafts DS, and each output shaft DS is drivingly connected to a pair of wheels W. In this embodiment, a first side gear S1, which is one of the pair of side gears SG, is connected to a connecting shaft JT, which is connected to a first output shaft DS1, which is one of the pair of output shafts DS, and the first output shaft DS1 is connected to one of the pair of wheels W. The connecting shaft JT is connected at one end to rotate integrally with the first side gear S1, extends in the axial direction L within the first housing chamber 1, and is rotatably supported at the other end relative to the case 10 by a fifth bearing B5 supported by a first cover 10a that forms the first housing chamber 1. The first output shaft DS1 is connected at one end to rotate integrally with the connecting shaft JT, and is supported at the other end by a member (not shown) inside the vehicle. A first seal member B6 supported by the first cover 10a is provided at the other end of the first output shaft DS1. The second side gear S2, which is the other of the pair of side gears SG, is connected to the second output shaft DS2, which is the other of the pair of output shafts DS, and the second output shaft DS2 is connected to the other of the pair of wheels W. One end of the second output shaft DS2 is connected to rotate integrally with the second side gear S2, and the other end is supported by a member (not shown) inside the vehicle. The other end of the second output shaft DS2 is provided with a second seal member B7 supported by a second cover 10b that forms the second housing chamber 2.

[0025] In this way, the differential gear mechanism DF distributes the torque transmitted from the rotor Rt via the input gear G1, counter gear mechanism CG (first counter gear G2, second counter gear G3), and differential input gear G4 to a pair of side gears SG serving as an output member OUT, and transmits the driving force to a pair of wheels W. In this way, the vehicle drive device 100 can transmit the torque of the rotating electric machine MG to the wheels W to drive the vehicle. In addition to the side gears SG and output shaft DS, the connecting shaft JT can also be considered as the output member OUT.

[0026] The rotating electric machine MG and gear mechanism TA constituting the vehicle drive device 100 are lubricated (including cooled) by oil. Specifically, the above-mentioned bearings (B1 to B5), seal members (B6, B7), stator coil Sc of the rotating electric machine MG, etc. (collectively referred to as lubrication target parts) are lubricated and cooled by oil. The lubricating oil is supplied to the vehicle drive device 100 from at least one of a mechanical oil pump (not shown) driven by one or more driving power sources of the wheels W (the above-mentioned rotating electric machine MG, including an internal combustion engine if a separate internal combustion engine is provided), and an electric oil pump (not shown) driven by a driving power source other than the driving power source of the wheels W (for example, a rotating electric machine (motor) other than the rotating electric machine MG). Oil passages to the lubrication target parts are formed in the vehicle drive device 100, and oil is supplied from these oil pumps. However, forming oil passages from the oil pump to all the parts to be lubricated may result in the oil passages becoming complicated and the size of the vehicle drive system 100. Furthermore, if the number of oil passages increases, it may become necessary to increase the discharge capacity of the oil pump.

[0027] Therefore, instead of directly supplying oil from the oil pump, oil is often supplied from the oil pump to some of the lubrication target parts of the vehicle drive device 100 (for example, in this embodiment, the stator coil Sc of the rotating electrical machine MG), and the oil used to lubricate these lubrication target parts is then used to lubricate other lubrication target parts (for example, in this embodiment, the gear G and bearings (B1 to B5)). The oil used for lubrication falls due to gravity and accumulates inside the case 10 (in an oil reservoir located at the bottom of the case 10). Then, for example, the vehicle drive device 100 may be configured such that the oil from the oil reservoir is scooped up by rotating members such as various gears G included in the vehicle drive device 100, or oil falling on the rotating members such as the gears G is scattered by centrifugal force, thereby lubricating other lubrication target parts. In this embodiment, the first counter gear G2 and the differential input gear G4 are used as rotating members that scoop up oil from the oil reservoir at the bottom of the case 10. In this embodiment, the differential input gear G4, whose tooth surface is located furthest to the second side V2 in the vertical direction, mainly functions as the scooping gear G. That is, the gear mechanism TA supplies oil to the parts to be lubricated by scooping up the oil inside the case 10. In this embodiment, the parts to be lubricated by the scooping up of the gear mechanism TA (here, mainly the differential input gear G4) are the gears G and bearings (B1 to B5) that constitute the gear mechanism TA.

[0028] As described above, in this embodiment, the lubrication target portions are present in both the first housing chamber 1 and the second housing chamber 2. Therefore, after lubrication, the oil falls into the first housing chamber 1 and the second housing chamber 2 and accumulates at the bottom of each chamber. As described above, the scraping gear G is disposed in the second housing chamber 2. An oil pump may also be disposed in the first housing chamber 1. Therefore, it is preferable that the oil appropriately accumulates in both housing chambers. For this reason, to allow oil to flow between the first housing chamber 1 and the second housing chamber 2, an opening 5 that communicates the first housing chamber 1 and the second housing chamber 2 is formed in the partition wall 4 that separates the first housing chamber 1 and the second housing chamber 2, as shown in FIG. 3 and other figures. Furthermore, as shown in FIGS. 3 to 8, a valve body 6 is attached to this opening 5 to allow oil to flow from the first housing chamber 1 to the second housing chamber 2 and to restrict oil flow from the second housing chamber 2 to the first housing chamber 1.

[0029] As shown in FIG. 4 , the valve body 6 includes a plate 61, a fixed portion 62, a hinge portion 63, and a conical portion 64. The plate 61 and the fixed portion 62 are connected via the hinge portion 63 to be able to swing relative to each other. The fixed portion 62 is fixed to the partition wall 4 from the side of the second storage chamber 2 by a fastening member 69. Therefore, the valve body 6 is attached to the partition wall 4 so that the plate 61 swings with the fixed portion 62 and the hinge portion 63 fixed to the surface (mounting surface 42) of the partition wall 4 facing the second storage chamber 2. The plate 61 has an area larger than the opening 5, and a conical portion 64 is formed in the center of the plate 61. The conical portion 64 is formed so as to protrude toward the first storage chamber 1 when the valve body 6 is attached to the partition wall 4 (protruding beyond the portion surrounding the center of the plate 61).

[0030] 5, the valve body 6 is configured to assume a position (first position P1) in which the plate 61 is separated from the partition wall portion 4 when the vehicle is not tilted and is horizontal, that is, when the vehicle drive device 100 is in a horizontal position. When the valve body 6 is in the first position P1, the opening 5 is not blocked by the valve body 6 (the plate 61 and the conical portion 64), as shown in FIG. 5, and oil can freely flow between the first storage chamber 1 and the second storage chamber 2. In other words, oil can flow in both directions between the first storage chamber 1 and the second storage chamber 2.

[0031] On the other hand, in the position (second position P2) in which the plate 61 is in contact with the partition wall 4, the opening 5 is blocked by the valve body 6 (the plate 61 and the conical portion 64), as shown by the dashed line in FIG. 5 . Here, when oil attempts to flow from the second storage chamber 2 to the first storage chamber 1, the plate 61 is pressed toward the partition wall 4 by fluid pressure, and the flow of oil from the second storage chamber 2 to the first storage chamber 1 is blocked by the valve body 6. When oil attempts to flow from the first storage chamber 1 to the second storage chamber 2, the plate 61 is pressed in a direction away from the partition wall 4 by fluid pressure, and when the fluid pressure exceeds the force pressing the plate 61 against the partition wall 4, the opening 5 is opened. Therefore, the flow of oil from the first storage chamber 1 to the second storage chamber 2 is not blocked by the valve body 6, and the oil circulates. In this embodiment, the angle (opening angle θ) between the first position P1 and the second position P2 is approximately 5 to 10 degrees.

[0032] As described above, the vehicle drive device 100 includes lubrication targets in both the first housing chamber 1 and the second housing chamber 2. For example, oil is scooped up by the differential input gear G4 from an oil reservoir at the bottom of the case 10, particularly from the oil reservoir at the bottom of the second housing chamber 2, and the oil is then passed through a catch tank and oil passages (not shown) to lubricate the input gear G1, the first counter gear G2, the second counter gear G3, the first bearing B1, the second bearing B2, the third bearing B3, the fourth bearing B4, the fifth bearing B5, the first seal member B6, and the second seal member B7. Similarly, the stator coil Sc of the rotating electric machine MG can be cooled through a catch tank and oil passages (not shown). For example, the oil that lubricates the first bearing B1 and the oil that cools the stator coil Sc falls into the first housing chamber 1 and is stored in the oil reservoir at the bottom of the first housing chamber 1. Then, the oil stored in the first housing chamber 1 flows through the opening 5 of the partition wall portion 4 into the oil reservoir in the second housing chamber 2. By circulating the oil within the case 10 in this manner, the rotating electrical machine MG and the gear mechanism TA are continuously and appropriately lubricated.

[0033] However, when oil can flow between the two housing chambers in this way, the oil may become concentrated in one of the housing chambers due to inertial forces caused by the vehicle tilting or turning or accelerating. For example, as shown in Figure 7, if oil is concentrated toward the first housing chamber 1 and the amount of oil in the second housing chamber 2 decreases, the oil scooped up by the gear G may decrease, resulting in insufficient oil being supplied to the parts to be lubricated via the catch tank or oil passage. In the example of Figure 7, both the differential input gear G4 and the first counter gear G2 are located above the oil level of the accumulated oil LQ, and are unable to scoop up the oil.

[0034] However, in this embodiment, as described above, the opening 5 is provided with the valve body 6. As shown in FIG. 6, when the vehicle drive device 100 is tilted toward the first axial side L1, the opening 5 is blocked by the valve body 6. This blocks the flow of oil from the second housing chamber 2 to the first housing chamber 1, suppresses the amount of oil flowing out into the first housing chamber 1, and allows enough oil to remain in the second housing chamber 2 for scooping up by the gear G. In the example shown in FIG. 6, a portion of the tooth surface of the differential input gear G4 and the entire tooth surface of the first counter gear G2 are immersed in the oil LQ accumulated in the second housing chamber 2. Therefore, in the example shown in FIG. 6, the differential input gear G4 and the first counter gear G2 can scoop up the oil.

[0035] In this way, the valve body 6 is attached to the opening 5 formed in the partition wall 4 that separates the first storage chamber 1 and the second storage chamber 2 so as to allow oil to flow from the first storage chamber 1 to the second storage chamber 2 and to restrict oil flow from the second storage chamber 2 to the first storage chamber 1. This makes it possible to limit a drop in the oil level in the second storage chamber 2 even when the oil level is tilted due to inertial forces caused by tilting of the vehicle or turning or acceleration / deceleration. Furthermore, by limiting the drop in the oil level in the second storage chamber 2, oil can be appropriately supplied to the parts to be lubricated by the scraping up of the gear G.

[0036] As described above, in this embodiment, the rotating electric machine MG is accommodated in the first accommodation chamber 1, and the gear mechanism TA is accommodated in the second accommodation chamber 2. According to this embodiment, even if the oil level is tilted due to inertial forces caused by tilting, turning, or acceleration / deceleration of the vehicle, a drop in the oil level in the second accommodation chamber 2 is suppressed. For example, when lubricating (cooling) oil is supplied to each part of the vehicle drive device 100 by scooping up the gear G included in the gear mechanism TA accommodated in the second accommodation chamber 2, it is possible to suppress the oil level from becoming lower than the gear G, which would prevent the gear G from scooping up the oil. In other words, when the configuration of this embodiment is applied to a configuration in which the gear mechanism TA is accommodated in the second accommodation chamber 2, each part can be appropriately lubricated by the oil scooping up by the gear G.

[0037] In this embodiment, the vehicle drive device 100 includes an oil pump (electric oil pump) (not shown) that supplies oil to the rotating electric machine MG, and a strainer (not shown) that removes impurities from the oil drawn by the oil pump. The strainer is housed in the second housing chamber 2. The oil pump is also housed in the second housing chamber 2. As shown in FIGS. 3 and 8, a strainer arrangement hole 9 is formed in the partition wall portion 4, in which a strainer that removes impurities from the oil drawn by the oil pump is disposed. Although not shown, a valve body may also be disposed in this strainer arrangement hole 9.

[0038] Incidentally, the oil stored inside the case 10 deteriorates due to the inclusion of dust generated by friction of the bearings and changes in composition (e.g., oxidation) caused by contact with high-temperature components such as the stator coil Sc. Deteriorated oil has reduced lubricating and cooling performance, so the oil inside the case 10 is replaced periodically. In this case, providing a drain hole communicating with the first housing chamber 1 and a drain hole communicating with the second housing chamber 2 in consideration of the possibility that the valve body 6 may restrict the flow of oil between the first housing chamber 1 and the second housing chamber 2 may complicate the structure of the case 10 and increase costs. Furthermore, when replacing the oil, work must be done to drain the oil from two locations, which increases the number of steps and may increase maintenance costs.

[0039] For this reason, in this embodiment, as shown in FIG. 9 , a drain hole 7 that connects the first storage chamber 1 to the outside of the case 10 is formed in the bottom wall portion 21 of the first storage chamber 1, and a communication hole 8 that connects the second storage chamber 2 to the drain hole 7. A drain plug 79 is inserted into and detachably fixed to the drain hole 7. By providing such a drain hole 7 and communication hole 8, oil stored in the first storage chamber 1 and the second storage chamber 2 can be discharged through the single drain hole 7. Even if the valve body 6 is attached to the opening 5 as in this embodiment, when oil is discharged, the oil in the second storage chamber 2 is not hindered from being discharged through the communication hole 8 that connects the drain hole 7 to the second storage chamber 2. Compared to a case in which a drain hole is provided in each of the first storage chamber 1 and the second storage chamber 2, the structure of the case 10 can be simplified and the number of parts can be reduced. The drain hole 7 is blocked by a drain plug 79, but oil can be drained from both the first storage chamber 1 and the second storage chamber 2 simply by removing this one drain plug 79, which also improves the efficiency of the work required to drain oil.

[0040] 9, the communication hole 8 is formed inside the bottom wall portion 21. Specifically, the communication hole 8 includes a first opening 81 that opens to a side surface of the drain hole 7 and a second opening 82 that opens to an opposing surface (second-chamber opposing surface 22) of the bottom wall portion 21 that faces the second storage chamber 2. The communication hole 8 is formed to communicate between the first opening 81 and the second opening 82. That is, when the vehicle drive device 100 is mounted on the vehicle, the drain hole 7 and the communication hole 8 can be provided at a low position in the case 10, so that oil inside the case 10 can be appropriately discharged through the drain hole 7.

[0041] 9, in this embodiment, the position of the lower end of the first opening 81 (communication portion lower end position Z2) is located lower (on the second side V2 in the vertical direction) than the position (drain opening position Z1) of the opening of the drain hole 7 on the side of the first storage chamber 1 (drain opening 71). With this configuration, oil in the first storage chamber 1 is properly drained through the drain hole 7, and oil in the second storage chamber 2 is properly drained through the communication hole 8 connected to the side surface 78 of the drain hole 7 and the drain hole 7, even when the flow of oil into the first storage chamber 1 through the opening 5 is restricted by the valve body 6. Furthermore, because the lower end of the second opening 82 that opens into the second storage chamber opposing surface 22 is located lower than the opening of the drain hole 7 on the side of the first storage chamber 1 (drain opening 71), oil in the second storage chamber 2 can be drained until the lowest position of the communication hole 8 (communication portion lower end position Z2) becomes the oil level.

[0042] Furthermore, if the opening 5 formed in the partition wall portion 4 is located lower than the drain opening 71, which is the opening of the drain hole 7 on the side of the first storage chamber 1, the oil will flow into the second storage chamber 2 through the opening 5. Then, the oil can be discharged from the second storage chamber 2 through the communication hole 8 and the drain hole 7. It is preferable to place the drain opening 71 at the lowest position in the first storage chamber 1, but even if such a placement is difficult, the oil in the first storage chamber 1 can be properly discharged.

[0043] 9 , when the drain plug 79 is fixed to the drain hole 7, the drain hole 7 is closed, blocking not only communication between the first storage chamber 1 and the outside of the case 10, but also communication between the second storage chamber 2 and the drain hole 7 via the communication hole 8. That is, when the drain plug 79 is fixed to the drain hole 7, communication between the first storage chamber 1 and the second storage chamber 2 via the communication hole 8 is blocked. Therefore, when the drain plug 79 is fixed to the drain hole 7, it is possible to restrict oil from flowing between the first storage chamber 1 and the second storage chamber 2 via the communication hole 8.

[0044] Other Embodiments Other embodiments will be described below. Note that the configurations of the embodiments described below are not limited to being applied independently, and can also be applied in combination with the configurations of other embodiments as long as no contradiction occurs.

[0045] (1) In the above description, a vehicle drive device 100 having a three-shaft configuration in which three axes, namely, the first axis A1, the second axis A2, and the third axis A3, are arranged in parallel has been exemplified. However, the vehicle drive device 100 may have a two-shaft configuration in which, for example, the first axis A1 and the second axis A2 are arranged in parallel. Furthermore, the vehicle drive device 100 may have a configuration in which one or more axes different from the first axis A1, the second axis A2, and the third axis A3 are further arranged in parallel, resulting in four or more axes being arranged in parallel. Furthermore, the vehicle drive device 100 may have a single-shaft configuration in which the rotating electric machine MG, the gear G, and the differential gear mechanism DF are arranged on the same axis.

[0046] (2) In the above, a vehicle drive device 100 equipped with a rotating electric machine MG as a driving force source for the wheels W has been described as an example, but the vehicle drive device 100 may also be a hybrid drive device equipped with both an internal combustion engine and a rotating electric machine MG as a driving force source for the wheels W of the vehicle (for example, various types of hybrid drive devices such as a so-called one-motor parallel type or two-motor split type).

[0047] (3) In the above, an example has been given in which the rotating electric machine MG is housed in the first housing chamber 1 and the gear mechanism TA is housed in the second housing chamber 2. However, the gear mechanism TA may be housed in the first housing chamber 1 and the rotating electric machine MG may be housed in the second housing chamber 2. For example, a configuration may be possible in which an oil pump is housed in the second housing chamber 2 together with the rotating electric machine MG, and a valve body 6 is provided to close the opening 5 so that the oil pump can sufficiently suck oil.

[0048] (4) In the above example, the bottom wall 21 of the first storage chamber 1 is provided with the second storage chamber opposing surface 22, the second opening 82 of the communication hole 8 opens in the second storage chamber opposing surface 22, and the communication hole 8 is formed inside the bottom wall 21. However, the partition wall 4 may be continuous with the bottom wall 21, the second opening 82 may be provided in the surface of the partition wall 4 facing the second storage chamber 2 (the mounting surface 42), and the communication hole 8 may be formed inside the partition wall 4 and the bottom wall 21.

[0049] (5) In the above example, the position of the lower end of the first opening 81 (communication portion lower end position Z2) is located lower (on the second vertical side V2) than the position (drain opening position Z1) of the opening of the drain hole 7 on the side of the first storage chamber 1 (drain opening 71) (see FIG. 9). This is particularly useful when the position of the bottom of the second storage chamber 2 in the vertical direction V (second storage portion lowermost position Z3) is lower (on the second vertical side V2) than the position of the bottom of the first storage chamber 1 in the vertical direction V (approximately equal to drain opening position Z1 in the example of FIG. 9). For example, more oil can be discharged from the second storage chamber 2 than when oil is discharged from the second storage chamber 2 through the opening 5, the first storage chamber 1, and then the drain hole 7. However, the present invention is not limited to such a configuration. For example, when the position of the bottom of the second storage chamber 2 in the vertical direction V (lowest position Z3 of the second storage section) is higher than the position of the bottom of the first storage chamber 1 in the vertical direction V (drain opening position Z1) (in the case of the first side V1 in the vertical direction), the position of the lower end of the first opening 81 (lower end position Z2 of the communicating section) may be positioned above (first side V1 in the vertical direction) the position (drain opening position Z1) of the opening (drain opening 71) on the side of the first storage chamber 1 in the drain hole 7.

[0050] (6) In the above example, when the drain plug 79 is fixed to the drain hole 7, communication between the first storage chamber 1 and the second storage chamber 2 through the communication hole 8 is blocked. However, even when the drain plug 79 is fixed to the drain hole 7, this does not prevent communication between the first storage chamber 1 and the second storage chamber 2 through the communication hole 8. The cross-sectional area of ​​the communication hole 8 is smaller than the opening area of ​​the opening 5 of the partition wall portion 4. Furthermore, the tilt and inertial force of the vehicle while traveling often recover in a relatively short time. For this reason, the amount of oil that flows from the second storage chamber 2 to the first storage chamber 1 through the communication hole 8 is often limited, and the communication hole 8 does not need to be blocked when the drain plug 79 is fixed to the drain hole 7.

[0051] (7) As described above with reference to FIG. 9 , a configuration has been exemplified in which the bottom wall 21 of the first storage chamber 1 has a drain hole 7 that connects the first storage chamber 1 to the outside of the case 10, and a communication hole 8 that connects the second storage chamber 2 to the drain hole 7. However, this configuration is not limited thereto, and a drain hole (not shown) that connects the first storage chamber 1 to the outside of the case 10 may be formed in the bottom wall (unreferenced) of the second storage chamber 2. A drain plug is inserted into this drain hole and detachably fixed thereto. Since this drain hole is formed in the bottom wall of the second storage chamber 2, it connects the first storage chamber 1 to the outside of the case 10 and also connects the second storage chamber 2 to the outside of the case 10. That is, a drain hole is formed in the bottom wall of the second housing chamber 2, which connects the first housing chamber 1 to the outside of the case 10 and also connects the second housing chamber 2 to the outside of the case 10. Therefore, when the vehicle drive device 100 is mounted on a vehicle, oil in the case 10 can be appropriately discharged from the first housing chamber 1 and the second housing chamber 2 through the drain hole formed at a low position in the case 10.

[0052] (8) In the above, as described with reference to FIG. 9 , a configuration has been exemplified in which a drain hole 7 is formed in the bottom wall 21 of the first storage chamber 1, connecting the first storage chamber 1 to the outside of the case 10, and a communication hole 8 is provided connecting the second storage chamber 2 to the drain hole 7. Although not shown, it has been explained that a drain hole connecting the first storage chamber 1 to the outside of the case 10 may also be formed in the bottom wall of the second storage chamber 2. However, this configuration is not limited to this, and a drain hole (not shown) connecting the second storage chamber 2 to the outside of the case 10 may also be formed in the bottom wall (unreferenced) of the second storage chamber 2. A drain plug is inserted into this drain hole and detachably fixed. As described with reference to FIG. 5 and other figures, the opening 5 formed between the first storage chamber 1 and the second storage chamber is provided with a valve body 6, thereby regulating the flow of oil from the second storage chamber 2 to the first storage chamber 1. However, the flow of oil from the first housing chamber 1 to the second housing chamber 2 is not restricted by the valve body 6, and so the oil flows from the first housing chamber 1 to the second housing chamber 2 through the opening 5. That is, the drain hole formed in the bottom wall of the second housing chamber 2 also serves as a drain hole that connects the first housing chamber 1 to the outside of the case 10. Therefore, when the vehicle drive device 100 is mounted on a vehicle, the oil in the case 10 can be appropriately discharged from the first housing chamber 1 and the second housing chamber 2 through the drain hole formed at a low position in the case 10.

[0053] [Outline of the embodiment] The above-described vehicle drive device (100) will now be briefly described.

[0054] In one aspect, a vehicle drive device (100) includes a rotating electric machine (MG) that is a driving force source for wheels (W), an output member (OUT) that is drivingly connected to the wheels (W), a gear mechanism (TA) that drivingly connects the rotating electric machine (MG) and the output member (OUT), and a case (10) that houses the rotating electric machine (MG) and the gear mechanism (TA), and the case (10) is partitioned by a partition wall portion (4) of the case (10) and includes a first housing chamber ( The case (10) includes a first storage chamber (1) and a second storage chamber (2) that stores the gear mechanism (TA), and the gear mechanism (TA) supplies oil to a location to be lubricated by scooping up oil inside the case (10). The partition wall portion (4) has an opening (5) that communicates with the first storage chamber (1) and the second storage chamber (2). A valve body (6) is attached to the opening (5) so as to allow oil to flow from the first storage chamber (1) to the second storage chamber (2) and to regulate the flow of oil from the second storage chamber (2) to the first storage chamber (1).

[0055] According to this configuration, a partition wall separating the first and second housing chambers has an opening that connects the first and second housing chambers. A valve body is attached to this opening to allow oil to flow from the first housing chamber to the second housing chamber and to restrict oil flow from the second housing chamber to the first housing chamber. Therefore, even if the oil level tilts due to inertial forces caused by vehicle tilt, turning, or acceleration / deceleration, the oil level in the second housing chamber can be prevented from dropping. That is, even if the oil level tilts, the gear mechanism housed in the second housing chamber can scoop up the oil inside the case, thereby supplying the oil to the lubrication target area. Thus, this configuration provides a vehicle drive device that prevents oil from concentrating in any one of the multiple housing chambers formed in the case.

[0056] In addition, the vehicle drive device (100) preferably includes an oil pump that supplies oil to the rotating electric machine (MG) and a strainer that removes impurities from the oil sucked by the oil pump, and the strainer is preferably housed in the second housing chamber (2).

[0057] According to this configuration, even if the oil level is inclined, the oil to be supplied to the rotating electrical machine (MG) can be sucked by the oil pump through a strainer provided in the second storage chamber (2), which limits the drop in the oil level.

[0058] In addition, the vehicle drive device (100) preferably has a drain hole (7) formed in the bottom wall portion (21) of the first storage chamber (1) that connects the first storage chamber (1) to the outside of the case (10), a drain plug (79) inserted into the drain hole (7) and removably fixed thereto, and a communication hole (8) that connects the second storage chamber (2) to the drain hole (7).

[0059] By providing such a drain hole (7) and a communication hole (8), the oil stored in the first storage chamber (1) and the second storage chamber (2) can be discharged through the single drain hole (7). That is, even if the valve body (6) is attached to the opening (5), when discharging oil, the oil in the second storage chamber (2) can also be discharged through the communication hole (8) that connects the drain hole (7) and the second storage chamber (2). That is, the valve body (6) attached to the opening (5) does not prevent the oil from being discharged from the second storage chamber (2). Therefore, compared to a case in which oil drain holes are provided in each of the first storage chamber (1) and the second storage chamber (2) (a drain hole (7) for the first storage chamber (1) and a separate drain hole for the second storage chamber (2)), the structure of the case (10) can be simplified and the number of parts can be reduced. The drain hole (7) is blocked by a drain plug (79), but the oil in both the first storage chamber (1) and the second storage chamber (2) can be drained by simply removing this one drain plug (79), which also improves the efficiency of the work of draining the oil.

[0060] Furthermore, it is preferable that the vehicle drive device (100) is configured such that the bottom wall portion (21) has a second storage chamber opposing surface (22) facing the second storage chamber (2), the communication hole (8) is formed inside the bottom wall portion (21), the communication hole (8) has a first opening (81) that opens to a side surface of the drain hole (7) and a second opening (82) that opens to the second storage chamber opposing surface (22), and is configured to communicate between the first opening (81) and the second opening (82).

[0061] According to this configuration, when the vehicle drive device (100) is mounted on a vehicle, the drain hole (7) and the communication hole (8) can be provided at a low position in the case (10), so that oil in the case (10) can be properly discharged through the drain hole (7).

[0062] In addition, it is preferable that the vehicle drive device (100) has a lower end (Z2) of the first opening (81) located below (V2) the opening (71) of the drain hole (7) on the side of the first storage chamber (1).

[0063] With this configuration, oil in the first storage chamber (1) is properly discharged through the drain hole (7), and oil in the second storage chamber (2) is properly discharged through the communication hole (8) connected to the side surface (78) of the drain hole (7) and the drain hole (7), even when the flow of oil through the opening (5) to the first storage chamber (1) is restricted by the valve body (6).

[0064] In addition, it is preferable that the vehicle drive device (100) is configured such that, when the drain plug (79) is fixed to the drain hole (7), communication between the second storage chamber (2) and the drain hole (7) via the communication hole (8) is blocked.

[0065] According to this configuration, when the drain plug (79) is fixed to the drain hole (7), not only is the drain hole (7) blocked to block communication between the first storage chamber (1) and the outside of the case (10), but communication between the second storage chamber (2) and the drain hole (7) via the communication hole (8) is also blocked. That is, when the drain plug (79) is fixed to the drain hole (7), communication between the first storage chamber (1) and the second storage chamber (2) via the communication hole (8) is also blocked. Therefore, when the drain plug (79) is fixed to the drain hole (7), rather than when oil is being discharged from the case (10), it is possible to restrict oil from flowing between the first storage chamber (1) and the second storage chamber (2) via the communication hole (8).

[0066] In the vehicle drive device (100), it is preferable that a drain hole communicating between the first storage chamber (1) and the outside of the case (10) is formed in the bottom wall of the second storage chamber (2).

[0067] The drain hole is formed in the bottom wall of the second storage chamber (2), and therefore communicates the first storage chamber (1) with the outside of the case (10) and also communicates the second storage chamber (2) with the outside of the case (10). Therefore, when the vehicle drive device (100) is mounted on a vehicle, oil in the case (10) can be appropriately drained from the first storage chamber (1) and the second storage chamber (2) through the drain hole formed at a low position in the case (10). [Explanation of symbols]

[0068] 1: first storage chamber, 2: second storage chamber, 4: partition wall portion, 5: opening, 6: valve body, 7: drain hole, 8: communication hole, 10: case, 21: bottom wall portion, 22: second storage chamber opposing surface, 71: drain opening (opening of the drain hole on the side of the first storage chamber), 78: side surface, 79: drain plug, 81: first opening, 82: second opening, 100: vehicle drive device, G: gear, MG: rotating electric machine, OUT: output member, TA: gear mechanism, W: wheel, Z1: drain opening position (position of the opening of the drain hole on the side of the first storage chamber), Z2: communication portion lower end position (lower end of the second opening).

Claims

1. a rotating electric machine that is a driving force source for the wheels; an output member drivingly connected to the wheel; a gear mechanism that drivingly couples the rotary electric machine and the output member; a case that houses the rotating electric machine and the gear mechanism, the case is partitioned by a partition wall portion of the case, and includes a first housing chamber that houses the rotating electric machine and a second housing chamber that houses the gear mechanism, The gear mechanism supplies oil to a target lubrication point by scooping up oil inside the case, an opening portion that communicates the first storage chamber with the second storage chamber is formed in the partition wall portion; a valve body attached to the opening to allow oil to flow from the first housing chamber to the second housing chamber and to restrict oil to flow from the second housing chamber to the first housing chamber, the valve body includes a plate, a fixed portion fixed to the partition wall portion from the side of the second storage chamber, and a hinge portion swingably connecting the plate to the fixed portion, the plate includes a conical portion that protrudes toward the first storage chamber when the valve body is attached to the partition wall portion, and a flat portion that surrounds the conical portion, a direction along a rotation axis of the rotary electric machine is defined as an axial direction, a side on which the first accommodating chamber is located with respect to the second accommodating chamber is defined as an axial first side, and an opposite side thereto is defined as an axial second side, the flat surface of the valve body abuts against the mounting surface of the partition wall portion from the second axial side; a portion of the plate that forms the conical portion is positioned on the first axial side of the end face on the second axial side of the mounting surface, and is positioned within a through hole in the partition wall portion that forms the opening, thereby regulating the flow of oil from the second storage chamber to the first storage chamber.

2. an oil pump that supplies oil to the rotating electrical machine; a strainer that removes impurities from the oil drawn by the oil pump, The vehicle drive device according to claim 1 , wherein the strainer is accommodated in the second accommodation chamber.

3. a drain hole communicating the first storage chamber with the outside of the case is formed in a bottom wall of the first storage chamber; A drain plug is inserted into the drain hole and removably fixed thereto, The vehicle drive device according to claim 1 or 2, further comprising a communication hole that communicates the second housing chamber with the drain hole.

4. the bottom wall portion includes a second storage chamber facing surface facing the second storage chamber, The communication hole is formed inside the bottom wall portion, 4. The vehicle drive device according to claim 3, wherein the communication hole has a first opening that opens to a side surface of the drain hole and a second opening that opens to a surface facing the second storage chamber, and is formed to communicate between the first opening and the second opening.

5. The vehicle drive device according to claim 4 , wherein a lower end of the first opening is located below an opening of the drain hole on the side of the first housing chamber.

6. The vehicle drive device according to claim 3 , wherein communication between the second accommodating chamber and the drain hole via the communication hole is blocked when the drain plug is fixed to the drain hole.

7. The vehicle drive device according to claim 1 or 2, wherein a drain hole that communicates the first housing chamber with the outside of the case is formed in a bottom wall portion of the second housing chamber.

Images