Vehicle drive systems

Abstract

Properly supply oil to the connection between the rotor shaft and the input shaft. [Solution] The first shaft is formed in a hollow cylindrical shape with an internal space, and the second end region 10 of the second shaft is inserted into the first end region 20 of the first shaft, and the first connecting portion 21 of the first end region 20 and the second connecting portion 12 of the second end region 10 are connected so that the first shaft and the second shaft rotate integrally. The second shaft includes an axial oil passage 11 that opens on the axial second side L2, and a radial oil passage 13 that connects the axial oil passage 11 and the outer circumferential surface 10b of the second end region 10, and an oil passage forming member 3 is arranged in the internal space, and the oil passage forming member 3 includes an internal oil passage 31 that extends along the axial direction L from the supplied portion and opens on the axial first side L1, and the end of the oil passage forming member 3 on the axial first side L1 is connected to the axial oil passage 11.

Description

Technical Field

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

Background Art

[0002] For example, Japanese Laid-Open Patent Publication No. 2016-014445 (Patent Document 1) discloses an invention related to an in-wheel motor drive device.

[0003] In the invention disclosed in Patent Document 1, in order to eliminate the step formed at the connection portion between the rotor shaft (24) and the input shaft (25), which had acted as a barrier when introducing the lubricating oil flowing in from the shaft end of the rotor shaft (24) to the input shaft (25) side, a hollow pipe member (80) forming a lubricating oil passage is provided inside the rotor shaft (24), the inner diameter of this hollow pipe member (80) and the inner diameter of the lubricating oil passage in the input shaft (25) are set to the same dimension, and the two are arranged to abut against each other in the axial direction.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of Invention

Problems to be Solved by the Invention

[0005] Incidentally, the inner surface of the rotor shaft (24) and the outer surface of the input shaft (25) are connected using splines for torque transmission. Therefore, lubrication is necessary at the connection point between the two, but Patent Document 1 does not specifically disclose anything about this. If a gap is formed between the input shaft (25) and the hollow pipe member (80), which are abutted axially with the same diameter, lubricating oil may enter the connection point through that gap. However, since this gap is at the boundary between the input shaft (25) and the hollow pipe member (80), it depends on the interaction between the two, and its size is not constant. Therefore, an appropriate amount of lubricating oil is not supplied to the intended location (i.e., the connection point).

[0006] Therefore, there is a need for a technology that can properly supply oil to the connection between the rotor shaft and the input shaft. [Means for solving the problem]

[0007] The vehicle drive system relating to this disclosure is A rotating electric machine equipped with a rotor, A rotor shaft fixed to the rotor so as to rotate integrally with the rotor, An input shaft, which is arranged coaxially with the rotor shaft and has a first gear, An output member that is driven and connected to the wheel, A power transmission mechanism comprising a second gear that meshes with the first gear, and which drives and connects the second gear and the output member, Equipped with, One of the rotor shaft and the input shaft is designated as the first shaft, and the other of the rotor shaft and the input shaft is designated as the second shaft. The direction along the axis of the first axis is defined as the axial direction, the direction perpendicular to the axis is defined as the radial direction, the side on which the second axis is positioned relative to the first axis in the axial direction is defined as the first axial side, and the side on the opposite side of the first axial side in the axial direction is defined as the second axial side. The first shaft is formed in a hollow cylindrical shape having an internal space, The second end region of the second shaft, which is the second end region in the axial direction of the first shaft, is inserted into the first end region, which is the first end region in the axial direction of the first shaft, and the first connecting portion provided on the inner circumferential surface of the first end region and the second connecting portion provided on the outer circumferential surface of the second end region are connected so that the first shaft and the second shaft rotate integrally. The second shaft comprises an axial oil passage opening to the second axial side and a radial oil passage connecting the axial oil passage and the outer circumferential surface of the second end region. An oil passage forming member is arranged in the aforementioned internal space so as to extend along the axial direction. The oil passage forming member comprises a supply portion that receives oil, and an internal oil passage that extends from the supply portion along the axial direction and opens to the first axial side. The axial first end of the oil passage forming member is connected to the axial oil passage.

[0008] With this configuration, the oil supplied to the supplied portion can be supplied between the inner circumferential surface of the first end region and the outer circumferential surface of the second end region via the internal oil passage of the oil passage forming member, the axial oil passage of the second shaft, and the radial oil passage. Therefore, it becomes possible to properly supply oil to the connection portion between the rotor shaft and the input shaft.

[0009] Further features and advantages of the technology relating to this disclosure will become clearer from the following description of exemplary and non-limiting embodiments, with reference to the drawings. [Brief explanation of the drawing]

[0010] [Figure 1] A schematic diagram showing the general configuration of a vehicle's drive system. [Figure 2] Diagram showing the flow of oil from the oil passage on the case side. [Figure 3] Diagram showing the lubrication structure at the connection point between the rotor shaft and the input shaft. [Modes for carrying out the invention]

[0011] In the following, an embodiment of the vehicle drive device will be described by exemplifying a so-called three-axis E-axle, in which main rotating elements are disposed on the respective axes of a first virtual axis, a second virtual axis, and a third virtual axis that are arranged parallel to each other at different positions among the E-axles.

[0012] [Definitions] In the description of the present embodiment, the following definitions are adopted.

[0013] The direction along the first virtual axis Ax1 is defined as "axial direction L", one side in the axial direction L is defined as "first axial side L1", and the other side is defined as "second axial side L2". The direction orthogonal to the first virtual axis Ax1 is defined as "radial direction R". The direction circulating around the first virtual axis Ax1 is defined as "circumferential direction".

[0014] "Rotary electric machine" is used as a concept including any of a motor (electric motor), a generator (power generator), and a motor-generator that performs the functions of both the motor and the generator as required.

[0015] "Drivingly connected" refers to a state in which two rotating elements are connected so as to be capable of transmitting a driving force, and is used as a concept including 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 capable of transmitting a driving force via one or two or more transmission members. Such transmission members include various members that transmit rotation at the same speed or at a changed speed, and examples thereof include shafts, gear mechanisms, belts, chains, and the like. Further, such a transmission member may include an engagement device that selectively transmits rotation and driving force, for example, a friction engagement device, a meshing engagement device, or the like.

[0016] "Regarding the arrangement of two members, overlapping when viewed in a specific direction" means that there is a region where a virtual straight line parallel to the line of sight direction intersects both of the two members when the virtual straight line is moved in each direction orthogonal to the virtual straight line.

[0017] [Present Embodiment] As shown in Figure 1, the vehicle drive device 100 includes a rotating electrical machine MG provided with a rotor Ro, a rotor shaft 2 (corresponding to the "first shaft") fixed to the rotor Ro so as to rotate integrally with the rotor Ro, an input shaft 1 (corresponding to the "second shaft") arranged coaxially with the rotor shaft 2 and provided with a first gear G1, an output member 99 drivingly connected to wheels W, and a power transmission mechanism T. The power transmission mechanism T includes a second gear G2 meshing with the first gear G1, and is configured to drivingly connect the second gear G2 and the output member 99. In the present embodiment, the power transmission mechanism T includes a counter gear mechanism 8 and a differential gear mechanism 9. The vehicle drive device 100 is provided with a case C that accommodates the rotating electrical machine MG, the rotor shaft 2, the input shaft 1, the power transmission mechanism T, and the output member 99. In this example, the side where the input shaft 1 is disposed relative to the rotor shaft 2 in the axial direction L is defined as a first axial side L1, and the opposite side is defined as a second axial side L2.

[0018] In the present embodiment, the input shaft 1 and the rotor shaft 2 are disposed on a first virtual axis Ax1. That is, in this example, the first virtual axis Ax1 is the axis of the input shaft 1 and the rotor shaft 2. The input shaft 1 is connected to the rotor shaft 2 from the first axial side L1. The rotor shaft 2 is connected to the input shaft 1 from the second axial side L2. Both are configured to rotate integrally.

[0019] The counter gear mechanism 8 is disposed on a second virtual axis Ax2. That is, in this example, the second virtual axis Ax2 is the axis of the counter gear mechanism 8.

[0020] The differential gear mechanism 9 and the output member 99 are disposed on a third virtual axis Ax3. That is, in this example, the third virtual axis Ax3 is the axis of the differential gear mechanism 9 and the output member 99.

[0021] The drive rotation generated by the rotating electric machine MG is input to the input shaft 1 via the rotor shaft 2. This drive rotation is transmitted to the counter gear mechanism 8 via the second gear G2, which meshes with the first gear G1 on the input shaft 1. The counter shaft 80 of the counter gear mechanism 8 is provided with the second gear G2 and a third gear G3, which has a smaller diameter than the second gear G2. The drive rotation transmitted to the counter gear mechanism 8 via the second gear G2 is transmitted to the fourth gear G4 of the differential gear mechanism 9, which meshes with the third gear G3, and is then distributed by the differential gear mechanism 9 to a pair of output members 99, driving the left and right wheels W.

[0022] Oil is supplied to the rotor shaft 2 and input shaft 1, which are positioned on the first virtual axis Ax1. Lubrication and cooling by the oil are then performed on each of the rotating elements positioned on the first virtual axis Ax1.

[0023] In this embodiment, the rotor shaft 2 and the input shaft 1 are rotatably supported at three points in the axial direction L by the first bearing B1, the second bearing B2, and the third bearing B3. In this example, the only bearings supporting the rotor shaft 2 and the input shaft 1 on the first virtual axis Ax1 are the first bearing B1, the second bearing B2, and the third bearing B3. In other words, in this example, no bearings supporting the input shaft 1 are located between the axial end L1 of the rotor shaft 2 and the axial direction L of the first gear G1. Also, in this example, the only rolling bearings located on the first virtual axis Ax1 are the first bearing B1, the second bearing B2, and the third bearing B3.

[0024] The first bearing B1 is positioned on the second axial side L2 relative to the rotor Ro and the first gear G1. In this example, the first bearing B1 is configured to support the rotor shaft 2 from the outside in the radial direction R.

[0025] The second bearing B2 is positioned on the first axial side L1 relative to the rotor Ro and the first gear G1. In this example, the second bearing B2 is configured to support the input shaft 1 from the outside in the radial direction R. The first gear G1 is positioned on the first axial side L1 relative to the rotor Ro.

[0026] The third bearing B3 is positioned between the rotor Ro and the first gear G1 in the axial direction L. In this example, the third bearing B3 is configured to support the rotor shaft 2 from the outside in the radial direction R.

[0027] As shown in Figure 2, the rotor shaft 2 and the input shaft 1 are connected in such a way that their axial arrangement regions overlap.

[0028] The rotor shaft 2 is formed in a hollow cylindrical shape having an internal space 23. In this embodiment, the rotor shaft 2 comprises a large-diameter cylindrical portion 25 and a small-diameter cylindrical portion 26 having a smaller diameter than the large-diameter cylindrical portion 25. The large-diameter cylindrical portion 25 and the small-diameter cylindrical portion 26 are continuous in the axial direction L. That is, in this embodiment, both ends of the rotor shaft 2 in the axial direction L are open.

[0029] The large-diameter cylindrical portion 25 is positioned on the second axial side L2 relative to the small-diameter cylindrical portion 26. The large-diameter cylindrical portion 25 is supported from the outside in the radial direction R by the first bearing B1 and is rotatable relative to the case C.

[0030] The small-diameter cylindrical portion 26 is supported from the outside in the radial direction R by the third bearing B3 and is rotatable relative to the case C.

[0031] By inserting a portion of the input shaft 1 into the rotor shaft 2, the rotor shaft 2 and the input shaft 1 are arranged to have overlapping portions in the axial direction L. In this overlapping portion in the axial direction L, the rotor shaft 2 and the input shaft 1 are connected so as to rotate as a single unit.

[0032] In other words, the second end region 10, which is the end region of the second axial side L2 of the input shaft 1, is inserted into the first end region 20, which is the end region of the first axial side L1 of the rotor shaft 2. The first connecting portion 21 provided on the inner circumferential surface 20a of the first end region 20 and the second connecting portion 12 provided on the outer circumferential surface 10b of the second end region 10 are connected so that the rotor shaft 2 and the input shaft 1 rotate as a single unit.

[0033] In this embodiment, the axial second side L2 end of the input shaft 1 is formed in a hollow cylindrical shape and opens into the internal space 23 of the rotor shaft 2. This hollow portion at the axial second side L2 end of the input shaft 1 can be used as an oil passage. That is, the input shaft 1 is equipped with an axial oil passage 11 that opens to the axial second side L2.

[0034] An oil passage forming member 3 is arranged in the internal space 23 of the rotor shaft 2 so as to extend along the axial direction L. In this embodiment, the oil passage forming member 3 is made of a hollow round bar member and forms an oil passage inside it. However, the oil passage forming member 3 only needs to have a shape that can form an oil passage inside it, and does not necessarily have to be a hollow round bar member.

[0035] The oil passage forming member 3 comprises a supply portion 30 that receives oil, and an internal oil passage 31 that extends from the supply portion 30 along the axial direction L and opens to the axial first side L1.

[0036] In this embodiment, the supplied portion 30 is provided at the end of the second axial side L2 of the oil passage forming member 3. In this embodiment, the case C is provided with a case-side oil passage Ca that supplies oil to the supplied portion 30 through the second axial side L2 relative to the rotor shaft 2, and the supplied portion 30 is continuous with the case-side oil passage Ca. Oil is supplied to the case-side oil passage Ca by a mechanical or electric oil pump OP.

[0037] In this embodiment, the axial second side L2 end of the oil passage forming member 3, on which the supply portion 30 is provided, is fixed to the case C in a way that prevents rotation. This allows for high positional accuracy of the supply portion 30 relative to the case-side oil passage Ca, and enables reliable oil supply from the case-side oil passage Ca.

[0038] On the other hand, the axial first side L1 end of the oil passage forming member 3 is connected to the axial oil passage 11 inside the input shaft 1. In this embodiment, the axial first side L1 end of the oil passage forming member 3 is connected to the inner circumferential surface 10a of the input shaft 1 so as to be rotatable relative to it via a bearing Bn (here, a bush). Note that a rolling bearing such as a needle bearing may be provided instead of a sliding bearing such as a bush as the bearing Bn.

[0039] As described above, in this embodiment, the end of the oil passage forming member 3 on the second axial side L2 is provided with a fixed connecting portion 33 that is non-rotatably connected to the case C, and the end of the oil passage forming member 3 on the first axial side L1 is provided with a rotating connecting portion 34 that is rotatably connected to the input shaft 1. In other words, the oil passage forming member 3 is configured to allow the rotation of the input shaft 1 to which it is connected, but not to rotate itself. As a result, the oil passage forming member 3 is able to appropriately introduce oil supplied from the case-side oil passage Ca into the axial oil passage 11 inside the input shaft 1.

[0040] A portion of the oil supplied from the case-side oil passage Ca to the oil passage forming member 3 is used for cooling and lubrication of the rotating electric machine MG.

[0041] In this embodiment, the oil passage forming member 3 is provided with an outlet 32 ​​for discharging a portion of the oil flowing through the internal oil passage 31 into the internal space 23 of the rotor shaft 2. The rotor shaft 2 is provided with rotor shaft oil passages 24 (corresponding to the "first shaft oil passage") for supplying the oil supplied to its internal space 23 to the target location of the rotating electric machine MG. In the illustrated example, multiple rotor shaft oil passages 24 are provided so as to penetrate the rotor shaft 2 in the radial direction R. As the rotor shaft 2 rotates, the oil in the internal space 23 of the rotor shaft 2 is injected outward in the radial direction R through each rotor shaft oil passage 24 and supplied to various elements located radially outside the rotor shaft 2 in the radial direction R (for example, the coil end portion and the first bearing B1).

[0042] Then, the remaining portion of the oil supplied from the case-side oil passage Ca to the oil passage forming member 3 is used to lubricate the connection between the rotor shaft 2 and the input shaft 1, that is, the first connecting portion 21 provided in the first end region 20 of the rotor shaft 2 and the second connecting portion 12 provided in the second end region 10 of the input shaft 1.

[0043] As shown in Figure 3, the first connecting portion 21 is provided with a first rotational engaging portion 21a. The second connecting portion 12 is provided with a second rotational engaging portion 12a that engages with the first rotational engaging portion 21a in the circumferential direction. The first rotational engaging portion 21a and the second rotational engaging portion 12a, which engage with each other, are constructed using splines. However, they may also be constructed using, for example, a key and a keyway.

[0044] In this embodiment, a first rotational engagement portion 21a is formed on a part of the inner circumferential surface 20a of the first end region 20 of the rotor shaft 2. A second rotational engagement portion 12a is formed on a part of the outer circumferential surface 10b of the second end region 10 of the input shaft 1. That is, in a part of the axial overlap region where the rotor shaft 2 and the input shaft 1 overlap in the axial direction L, an engagement region Aa is formed in which the first rotational engagement portion 21a and the second rotational engagement portion 12a engage.

[0045] In this embodiment, the first connecting portion 21 further comprises a first radial fitting portion 21b. The second connecting portion 12 further comprises a second radial fitting portion 12b that fits radially R to the first radial fitting portion 21b. In this example, the first radial fitting portion 21b and the second radial fitting portion 12b that fit together are fitted by gap fitting (an example of a spigot structure). However, they may also be fitted by press fitting or shrink fitting, for example.

[0046] In this embodiment, a first radial fitting portion 21b is formed on a part of the inner circumferential surface 20a of the first end region 20 of the rotor shaft 2. A second radial fitting portion 12b is formed on a part of the outer circumferential surface 10b of the second end region 10 of the input shaft 1. That is, a fitting region Ab is formed in a part of the axial overlap region where the rotor shaft 2 and the input shaft 1 overlap in the axial direction L, where the first radial fitting portion 21b and the second radial fitting portion 12b fit together.

[0047] Thus, an engagement region Aa is formed in a part of the axial overlap region where the rotor shaft 2 and the input shaft 1 overlap in the axial direction L, and a fitting region Ab is formed in another part of the axial overlap region.

[0048] In this embodiment, the engagement region Aa is positioned on the second axial side L2 relative to the fitting region Ab. The fitting region Ab is positioned on the first axial side L1 relative to the engagement region Aa.

[0049] Here, the input shaft 1 is provided with a radial oil passage 13 that connects the axial oil passage 11 and the outer circumferential surface 10b of the second end region 10. The radial oil passage 13 penetrates the second end region 10 of the input shaft 1 in the radial direction R. With this configuration, oil from the axial oil passage 11 can be supplied to the space between the outer circumferential surface 10b of the second end region 10 and the inner circumferential surface 20a of the first end region 20 via the radial oil passage 13. Therefore, oil can be appropriately supplied to the engagement region Aa where the first rotational engagement portion 21a and the second rotational engagement portion 12a engage.

[0050] In this embodiment, the radial oil passage 13 is located between the engagement region Aa and the fitting region Ab in terms of axial direction L. Therefore, the oil supplied between the outer circumferential surface 10b of the second end region 10 and the inner circumferential surface 20a of the first end region 20 via the radial oil passage 13 can be appropriately distributed not only to the engagement region Aa but also to the fitting region Ab where the first radial fitting portion 21b and the second radial fitting portion 12b are fitted together.

[0051] In this embodiment, an oil reservoir 4 is formed between the inner circumferential surface 20a of the first end region 20 and the outer circumferential surface 10b of the second end region 10, where oil accumulates. With this configuration, oil can be temporarily stored between the outer circumferential surface 10b of the second end region 10 and the inner circumferential surface 20a of the first end region 20. Therefore, the first connecting portion 21 and the second connecting portion 12 can be stably lubricated.

[0052] In this embodiment, the oil reservoir 4 is positioned to connect the radial oil passage 13 with the first rotational engagement portion 21a and the second rotational engagement portion 12a (engagement region Aa). In other words, the oil reservoir 4 extends further in the axial direction L towards the side where the engagement region Aa is provided (the second axial side L2) than the radial oil passage 13. This makes it easier to preferentially supply oil to the engagement region Aa, which has a higher need for lubrication than the fitting region Ab. In this example, the oil reservoir 4 is a space formed between the outer circumferential surface 10b of the second end region 10 and the inner circumferential surface 20a of the first end region 20 by the missing spline portions in the first rotational engagement portion 21a and the second rotational engagement portion 12a.

[0053] In this embodiment, a communication oil passage 22 is formed in the first end region 20, connecting the inner circumferential surface 20a and the outer circumferential surface 20b of the first end region 20. In other words, the communication oil passage 22 penetrates the first end region 20 on the rotor shaft 2 in the radial direction R. This communication oil passage 22 is positioned axially first L1 further than the radial oil passage 13, and is positioned to overlap with the fitting region Ab in a radial direction R view. As a result, the oil supplied from the radial oil passage 13 between the inner circumferential surface 20a of the first end region 20 and the outer circumferential surface 10b of the second end region 10 is supplied to the first radial fitting portion 21b and the second radial fitting portion 12b (fitting region Ab), and to the communication oil passage 22. The oil supplied to the communication oil passage 22 is then supplied to the third bearing B3. In this example, the third bearing B3 is positioned in a location that overlaps with the communication oil passage 22 in a radial R view, making it easier to supply oil to the third bearing B3. With this configuration, the fitting region Ab can be lubricated using the oil flowing into the axial oil passage 11 of the input shaft 1, and the third bearing B3, which is positioned outside the radial R of the fitting region Ab, can also be lubricated. In this example, the resolver 7 (rotation detection device) is positioned in a location L2, which is second axially from the third bearing B3, and overlaps with the engagement region Aa in a radial R view. As a result, by positioning the third bearing B3, which supports the rotor shaft 2, in a location L1, first axially from the engagement region Aa, it is possible to place the resolver 7 in the space created near the engagement region Aa.

[0054] Thus, the vehicle drive system (100) relating to this disclosure is A rotating electric machine (MG) equipped with a rotor (Ro), A rotor shaft (2) is fixed to the rotor (Ro) so as to rotate integrally with the rotor (Ro), An input shaft (1) is arranged coaxially with the rotor shaft (2) and is provided with a first gear (G1), An output member (99) is driven and connected to the wheel (W), A power transmission mechanism (T) comprises a second gear (G2) that meshes with the first gear (G1), and drives and connects the second gear (G2) and the output member (99), Equipped with, One of the rotor shaft (2) and the input shaft (1) is designated as the first shaft (2), and the other of the rotor shaft (2) and the input shaft (1) is designated as the second shaft (1), The direction along the axis (Ax1) of the first axis (2) is defined as the axial direction (L), the direction perpendicular to the axis (Ax1) is defined as the radial direction (R), the side of the first axis (2) in the axial direction (L) on which the second axis (1) is positioned is defined as the first axial side (L1), and the side of the axial direction (L) opposite to the first axial side (L1) is defined as the second axial side (L2). The first axis (2) is formed in a hollow cylindrical shape having an internal space (23), The first end region (20), which is the end region on the first axial side (L1) of the first shaft (2), is inserted into the second end region (10), which is the end region on the second axial side (L2) of the second shaft (1), and the first connecting portion (21) provided on the inner circumferential surface (20a) of the first end region (20) and the second connecting portion (12) provided on the outer circumferential surface (10b) of the second end region (10) are connected so that the first shaft (2) and the second shaft (1) rotate integrally. The second shaft (1) includes an axial oil passage (11) that opens to the axial second side (L2), and a radial oil passage (13) that connects the axial oil passage (11) and the outer circumferential surface (10b) of the second end region (10). An oil passage forming member (3) is arranged in the internal space (23) so as to extend along the axial direction (L). The oil passage forming member (3) comprises a supply portion (30) that receives oil, and an internal oil passage (31) that extends from the supply portion (30) along the axial direction (L) and opens to the axial first side (L1), The axial first side (L1) end of the oil passage forming member (3) is connected to the axial oil passage (11).

[0055] With this configuration, the oil supplied to the supplied portion (30) can be supplied between the inner circumferential surface (20a) of the first end region (20) and the outer circumferential surface (10b) of the second end region (10) via the internal oil passage (31) of the oil passage forming member (3), the axial oil passage (11) of the second shaft (1), and the radial oil passage (13). Therefore, it becomes possible to properly supply oil to the connection portion between the rotor shaft (2) and the input shaft (1).

[0056] In this embodiment, The device comprises a case (C) housing the rotating electric machine (MG), the first shaft (2), the second shaft (1), and the power transmission mechanism (T), The case (C) is provided with a case-side oil passage (Ca) that supplies oil to the supplied part (30) through the axial second side (L2) relative to the first shaft (2), The first shaft (2) is provided with a first shaft oil passage (24) for supplying oil supplied to the internal space (23) to the target location of the rotating electric machine (MG), The oil passage forming member (3) is provided with an outlet (32) for discharging a portion of the oil flowing through the internal oil passage (31) into the internal space (23).

[0057] With this configuration, a portion of the oil supplied from the case-side oil passage (Ca) to the internal oil passage (31) of the oil passage forming member (3) can be supplied to the target area of ​​the rotating electric machine (MG). Therefore, the oil flowing through the internal oil passage (31) can be used to properly lubricate and cool the target area of ​​the rotating electric machine (MG).

[0058] In this embodiment, The first connecting portion (21) includes a first rotational engaging portion (21a), With the direction of rotation around the axis (Ax1) being the circumferential direction, the second connecting portion (12) includes a second rotational engaging portion (12a) that engages with the first rotational engaging portion (21a) in the circumferential direction. An oil reservoir (4) is formed between the inner circumferential surface (20a) of the first end region (20) and the outer circumferential surface (10b) of the second end region (10), where oil accumulates. The oil reservoir (4) is positioned to connect the radial oil passage (13) with the first rotational engagement portion (21a) and the second rotational engagement portion (12a).

[0059] With this configuration, oil supplied from the radial oil passage (13) between the inner circumferential surface (20a) of the first end region (20) and the outer circumferential surface (10b) of the second end region (10) can be temporarily stored in the oil reservoir (4). Therefore, the engagement portion between the first rotational engagement portion (21a) and the second rotational engagement portion (12a) can be lubricated with high reliability.

[0060] The first connecting portion (21) includes a first radial fitting portion (21b), The second connecting portion (12) includes a second radial fitting portion (12b) that fits radially (R) to the first radial fitting portion (21b), The first shaft (2) and the second shaft (1) are rotatably supported at three locations in the axial direction (L) by the first bearing (B1), the second bearing (B2), and the third bearing (B3). The first bearing (B1) is positioned on the second axial side (L2) relative to the rotor (Ro) and the first gear (G1), The second bearing (B2) is positioned on the first axial side (L1) with respect to the rotor (Ro) and the first gear (G1). The third bearing (B3) is positioned between the rotor (Ro) and the first gear (G1) in the axial direction (L) and is configured to support the first shaft (2) from the outside in the radial direction (R). A communication oil passage (22) is formed in the first end region (20) that connects the inner circumferential surface (20a) and the outer circumferential surface (10b) of the first end region (20). The oil supplied from the radial oil passage (13) between the inner circumferential surface (20a) of the first end region (20) and the outer circumferential surface (10b) of the second end region (10) is supplied to the first radial fitting portion (21b) and the second radial fitting portion (12b) and the communicating oil passage (22). The oil supplied to the aforementioned oil passage (22) is supplied to the third bearing (B3).

[0061] With this configuration, in a configuration in which the first shaft (2) and the second shaft (1) are supported at three points, the first radial fitting portion (21b) and the second radial fitting portion (12b) can be properly lubricated, and the third bearing (B3), which is positioned radially (R) outward with respect to the first shaft (2), can also be properly lubricated.

[0062] [Other Embodiments] Next, other embodiments will be described.

[0063] (1) In the above embodiment, an example was described in which the oil reservoir 4 extends further in the axial direction L to the side where the engagement region Aa is provided (second axial side L2) than the radial oil passage 13. However, the oil reservoir 4 is not limited to this example, and may extend further in the axial direction L1 than the radial oil passage 13, or may extend by an equivalent distance on both sides of the axial direction L from the radial oil passage 13.

[0064] (2) In the above embodiment, an example was described in which both ends of the rotor shaft 2 in the axial direction L are open. However, the example is not limited to this example, and the end of the rotor shaft 2 on the second axial side L2 (opposite to the input shaft 1) may be closed. In this case, the oil passage forming member 3 is preferably arranged to penetrate the closed portion of the rotor shaft 2.

[0065] (3) In the above embodiment, an example was described in which the first connecting portion 21 is provided with a first radial fitting portion 21b and the second connecting portion 12 is provided with a second radial fitting portion 12b. However, the invention is not limited to such an example, and these fitting portions may be omitted. Instead, the rotor shaft 2 and the input shaft 1 may be supported at four points in the axial direction L by four bearings.

[0066] (4) In the above embodiment, the supplied portion 30 is provided at the end of the second axial side L2 of the oil passage forming member 3, and an example has been described in which oil is supplied from the case-side oil passage Ca located on the second axial side L2. However, the embodiment is not limited to this example, and the supplied portion 30 may be provided at any location in the axial direction L of the oil passage forming member 3. In this case, the supplied portion 30 may be, for example, a radial through hole, and may be configured to receive oil from the outside in the radial direction R.

[0067] (5) In the above embodiment, an example was described in which the end of the first axial side L1 of the oil passage forming member 3 is connected to the inner circumferential surface 10a of the input shaft 1. However, the example is not limited to this example, and the end of the first axial side L1 of the oil passage forming member 3 may have the same diameter as the end of the second axial side L2 of the input shaft 1. In this case, the two may be abutted against each other in the axial direction L and connected from the outer circumference in the radial direction R by a connecting member or the like.

[0068] (6) In the above embodiment, an example was described in which the rotor shaft 2 corresponds to the "first shaft" and the input shaft corresponds to the "second shaft". However, the example is not limited to this example, and one of the rotor shaft 2 and the input shaft 1 may be designated as the first shaft, and the other of the rotor shaft and the input shaft as the second shaft. In other words, the above relationship may be reversed, and the rotor shaft 2 may be designated as the "second shaft" and the input shaft as the "first shaft".

[0069] (7) In the above embodiments, the vehicle drive system 100 was described using a three-axle E-axle as an example. However, the vehicle drive system 100 is not limited to such an example, and for example, it can also be applied to a two-axle E-axle equipped with a planetary gear reducer and a differential gear mechanism.

[0070] (8) The configurations disclosed in the embodiments described above can be applied in combination with configurations disclosed in other embodiments, as long as no inconsistencies arise. With regard to other configurations, the embodiments disclosed herein are merely illustrative in all respects. Therefore, various modifications can be made as appropriate without departing from the spirit of this disclosure. [Industrial applicability]

[0071] The technology disclosed herein can be used in vehicle drive systems. [Explanation of Symbols]

[0072] 100: Vehicle drive device, 1: Input shaft, 10: Second end region, 10a: Inner circumferential surface, 10b: Outer circumferential surface, 11: Axial oil passage, 12: Second coupling section, 12a: Second rotational engagement section, 12b: Second radial fitting part, 13: radial oil passage, 2: rotor shaft, 20: first end region, 20a: inner peripheral surface, 20b: outer peripheral surface, 21: first connecting part, 21a: first rotational engagement part, 21b: first radial fitting part, 22: communicating oil passage, 23: Internal space, 3: Oil path forming member, 30: Supplied part, 31: Internal oil path, 32: Discharge port, 4: Oil storage section, 99: Output member, MG: Rotating electric machine, Ro: Rotor, T: Power transmission mechanism, B1: First shaft B2: 2nd bearing, B3: 3rd bearing, C: Case, Ca: Case side oil passage, G1: 1st gear, G2: 2nd gear, W: Wheel, L: Axial direction, L1: Axial first side, L2: Axial second side, R: Radial direction

Claims

1. A rotating electric machine equipped with a rotor, A rotor shaft fixed to the rotor so as to rotate integrally with the rotor, An input shaft, which is arranged coaxially with the rotor shaft and has a first gear, An output member that is driven and connected to the wheel, A power transmission mechanism comprising a second gear that meshes with the first gear, and which drives and connects the second gear and the output member, Equipped with, One of the rotor shaft and the input shaft is designated as the first shaft, and the other of the rotor shaft and the input shaft is designated as the second shaft. The direction along the axis of the first axis is defined as the axial direction, the direction perpendicular to the axis is defined as the radial direction, the side on which the second axis is positioned relative to the first axis in the axial direction is defined as the first axial side, and the side on the opposite side of the first axial side in the axial direction is defined as the second axial side. The first shaft is formed in a hollow cylindrical shape having an internal space, The second end region of the second shaft, which is the second end region in the axial direction of the first shaft, is inserted into the first end region, which is the first end region in the axial direction of the first shaft, and the first connecting portion provided on the inner circumferential surface of the first end region and the second connecting portion provided on the outer circumferential surface of the second end region are connected so that the first shaft and the second shaft rotate integrally. The second shaft comprises an axial oil passage opening to the second axial side and a radial oil passage connecting the axial oil passage and the outer circumferential surface of the second end region. An oil passage forming member is arranged in the aforementioned internal space so as to extend along the axial direction. The oil passage forming member comprises a supply portion that receives oil, and an internal oil passage that extends from the supply portion along the axial direction and opens to the first axial side. The axial first end of the oil passage forming member is connected to the axial oil passage. Vehicle drive system.

2. The rotating electric machine, the first shaft, the second shaft, and the power transmission mechanism are housed in a case. The case is provided with a case-side oil passage that supplies oil to the supplied portion through the second axial side relative to the first shaft, The first shaft is provided with a first shaft oil passage for supplying oil supplied to the internal space to a target location of the rotating electric machine. The oil passage forming member is provided with an outlet for discharging a portion of the oil flowing through the internal oil passage into the internal space. The vehicle drive system according to claim 1.

3. The first connecting portion includes a first rotational engaging portion, With the direction of rotation around the aforementioned axis being defined as the circumferential direction, the second connecting portion includes a second rotational engaging portion that engages with the first rotational engaging portion in the circumferential direction. An oil reservoir is formed between the inner surface of the first end region and the outer surface of the second end region, where oil accumulates. The oil reservoir is positioned to connect the radial oil passage with the first and second rotational engagement portions. The vehicle drive system according to claim 1 or 2.

4. The first connecting portion includes a first radial fitting portion, The second connecting portion includes a second radial fitting portion that fits radially with respect to the first radial fitting portion, The first and second shafts are rotatably supported at three points in the axial direction by the first, second, and third bearings, The first bearing is positioned on the second axial side with respect to the rotor and the first gear. The second bearing is positioned on the first axial side with respect to the rotor and the first gear. The third bearing is positioned between the rotor and the first gear in the axial direction and is configured to support the first shaft from the radially outer side. A communication oil passage is formed in the first end region, connecting the inner circumferential surface and the outer circumferential surface of the first end region. The oil supplied from the radial oil passage between the inner circumferential surface of the first end region and the outer circumferential surface of the second end region is supplied to the first radial fitting portion and the second radial fitting portion and the communicating oil passage. The oil supplied to the aforementioned oil passage is supplied to the third bearing. The vehicle drive system according to claim 1 or 2.

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