Vehicle drive systems

Abstract

To provide a vehicular drive device which secures large reduction ratio of a pair of planetary gear mechanisms and furthermore is easily downsized.SOLUTION: A single pinion type second planetary gear mechanism 52 adjoins a double-pinion type first planetary gear mechanism 4 at a first side L1 in an axial direction, a single pinion type third planetary gear mechanism 53 adjoins the second planetary gear mechanism 52 at the first side L1 in the axial direction, a first ring gear R1 is connected to an input member 2, a first sun gear S1 is connected to a first output member 31, a first carrier C1 is connected to a second output member 32, a second sun gear S2 and a third sun gear S3 are the same with each other in the number of teeth, a second ring gear R2 and a third ring gear R3 are the same in the number of teeth, the second ring gear R2 and the third ring gear R3 are connected to each other, a drive-side sun gear Sd is drive-connected to a torque control device 5, a fixed-side sun gear Sf is fixed to a non-rotation member NR, the first carrier C1 and a second carrier C2 are connected to each other, and the first ring gear R1 and the a third carrier C3 are connected to each other.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a vehicle drive device comprising: an input member drivingly coupled to a drive source; a first output member drivingly coupled to a first wheel; a second output member drivingly coupled to a second wheel; a first planetary gear mechanism that distributes torque transmitted from the drive source to the input member to the first output member and the second output member; and a second planetary gear mechanism and a third planetary gear mechanism. Background Art

[0002] An example of such a vehicle drive device is disclosed in Patent Document 1 below. In the following description of the background art, reference signs in Patent Document 1 are cited in parentheses.

[0003] In the vehicle drive device of Patent Document 1, the first planetary gear mechanism (50A) is configured to distribute torque transmitted from a first drive source (MG2) to the input member (57) to the first output member (51) and the second output member (52). The first planetary gear mechanism (50A) is a double-pinion type planetary gear mechanism comprising a first sun gear (S3), a first carrier (C3), and a first ring gear (R3).

[0004] The second planetary gear mechanism (P2) is a single-pinion type planetary gear mechanism comprising a second sun gear (S2), a second carrier (C2), and a second ring gear (R2). The second planetary gear mechanism (P2) is arranged adjacent to one axial side (the right side in FIG. 1 of Patent Document 1) of the first planetary gear mechanism (50A). Further, the third planetary gear mechanism (P1) is a single-pinion type planetary gear mechanism comprising a third sun gear (S1), a third carrier (C1), and a third ring gear (R1). The third planetary gear mechanism (P1) is arranged adjacent to one axial side (the right side in FIG. 1 of Patent Document 1) of the second planetary gear mechanism (P2). Prior Art Documents Patent Documents

[0005] [Patent Document 1] Japanese Patent Publication No. 2017-32033 [Overview of the project] [Problems that the invention aims to solve]

[0006] In the vehicle drive system of Patent Document 1, the number of teeth of the second sun gear (S2) and the third sun gear (S1) are the same, and the number of teeth of the second ring gear (R2) and the third ring gear (R1) are the same. The third sun gear (S1) is driven and connected to the second drive source (MG1), and the second sun gear (S2) is fixed to a non-rotating member. The second carrier (C2) and the third carrier (C1) are connected so as to rotate integrally with each other. The third ring gear (R1) is connected via the first carrier (C1) so as to rotate integrally with the first output member (51). The second ring gear (R2) is connected so as to rotate integrally with the first sun gear (S3) and the second output member (52).

[0007] In the above configuration, the portion of the member connecting the gear of the first planetary gear mechanism (50A) with the gears of the second planetary gear mechanism (P2) and the third planetary gear mechanism (P1) that extends radially (vertical direction in Figure 1 of Patent Document 1) is arranged in the axial direction (left-right direction in Figure 1 of Patent Document 1), which tends to lead to an increase in the size of the vehicle drive system.

[0008] Furthermore, in the above configuration, the third sun gear (S1) functions as an input element to the second planetary gear mechanism (P2) and the third planetary gear mechanism (P1), and the second ring gear (R2) and the third ring gear (R1) function as output elements to the second planetary gear mechanism (P2) and the third planetary gear mechanism (P1). In such a configuration, due to the structure of the second planetary gear mechanism (P2) and the third planetary gear mechanism (P1), it is difficult to ensure a large reduction ratio for the second planetary gear mechanism (P2) and the third planetary gear mechanism (P1) (specifically, the reduction ratio from the input element to the output element). Therefore, it is necessary to ensure a large output torque for the second drive source (MG1), which leads to the challenge of increasing the size of the second drive source, and consequently the size of the vehicle's drive system.

[0009] Therefore, there is a need to realize a vehicle drive system that can be easily miniaturized while ensuring a large reduction ratio for a pair of planetary gear mechanisms. [Means for solving the problem]

[0010] In light of the above, the characteristic configuration of the vehicle drive system is: An input member connected to the first drive source, A first output member is driven and connected to the first wheel, A second output member is arranged coaxially with the first output member and is driven and connected to the second wheel, A first planetary gear mechanism distributes the torque transmitted from the first drive source to the input member to the first output member and the second output member, The second planetary gear mechanism, A vehicle drive system comprising a third planetary gear mechanism, The direction along the rotational axis of the first output member and the second output member is defined as the axial direction, one side in the axial direction is defined as the axial first side, and the other side in the axial direction is defined as the axial second side. The first planetary gear mechanism is a double pinion type planetary gear mechanism comprising a first sun gear, a first carrier, and a first ring gear. The first ring gear is connected to the input member so as to rotate integrally with it. The first sun gear is connected to the first output member so as to rotate integrally with it. The first carrier is connected to the second output member so as to rotate integrally with it. The second planetary gear mechanism is a single-pinion type planetary gear mechanism comprising a second sun gear, a second carrier, and a second ring gear, and is arranged adjacent to the first planetary gear mechanism on the axial side. The third planetary gear mechanism is a single-pinion type planetary gear mechanism comprising a third sun gear, a third carrier, and a third ring gear, and is arranged adjacent to the second planetary gear mechanism on the first axial side. The number of teeth of the second sun gear and the number of teeth of the third sun gear are the same. The number of teeth of the second ring gear and the number of teeth of the third ring gear are the same. The second ring gear and the third ring gear are connected so as to rotate integrally with each other. The driven sun gear, which is either the second sun gear or the third sun gear, is driven and connected to a torque control device that controls the torque transmitted to the driven sun gear. The fixed sun gear, which is the other of either the second sun gear or the third sun gear, is fixed to the non-rotating member. The first carrier and the second carrier are connected so as to rotate integrally with each other. The first ring gear and the third carrier are connected so that they rotate integrally with each other.

[0011] With this characteristic configuration, if a drive source (e.g., an electric motor) capable of transmitting torque in both the forward and negative rotation directions to the driven sun gear is used as the torque control device, the second planetary gear mechanism and the third planetary gear mechanism can function as a torque vectoring device that causes the torque transmitted to the first output member and the second output member to differ. Furthermore, if a device capable of transmitting reaction torque to the driven sun gear (e.g., a friction engagement brake) is used as the torque control device, the second planetary gear mechanism and the third planetary gear mechanism can function as a differential limiting device that limits the differential function of the first planetary gear mechanism. Furthermore, according to this characteristic configuration, the driven sun gear is an input element driven and connected to the torque control device, while the fixed sun gear is fixed to a non-rotating member. The second carrier and the third carrier are output elements connected to the first carrier and the first ring gear of the first planetary gear mechanism, respectively. This makes it easier to secure a large reduction ratio (specifically, the reduction ratio from the input element to the output element) for the second and third planetary gear mechanisms, which can function as a torque vectoring device or a differential limiting device, and to effectively transmit the torque of the torque control device to the wheels. Therefore, it is easier to miniaturize the torque control device, and consequently the vehicle drive system. Further, according to this characteristic configuration, the first planetary gear mechanism and the second planetary gear mechanism are arranged axially adjacent to each other. The first carrier of the first planetary gear mechanism and the second carrier of the second planetary gear mechanism are coupled to rotate integrally with each other. This facilitates size reduction of the coupling structure between the first carrier and the second carrier, and consequently size reduction of the vehicle drive device. As described above, according to this characteristic configuration, it is easy to achieve size reduction of the vehicle drive device while ensuring a large reduction ratio for the pair of planetary gear mechanisms. [BRIEF DESCRIPTION OF THE DRAWINGS]

[0012] [Figure 1] An axial cross-sectional view of the vehicle drive device according to the first embodiment [Figure 2] A skeleton diagram of the vehicle drive device according to the first embodiment [Figure 3] A partially enlarged cross-sectional view taken along the axial direction of the vehicle drive device according to the first embodiment [Figure 4] A speed diagram of the planetary gear mechanism according to the first embodiment [Figure 5] A speed diagram of the planetary gear mechanism according to the first embodiment [Figure 6] An axial cross-sectional view of the vehicle drive device according to the second embodiment [Figure 7] A skeleton diagram of the vehicle drive device according to the second embodiment [Figure 8] A partially enlarged cross-sectional view taken along the axial direction of the vehicle drive device according to the second embodiment [Figure 9] A diagram showing the positional relationship of each element when viewed in the axial direction in the vehicle drive device according to the second embodiment [Figure 10] An axial cross-sectional view of the vehicle drive device according to the third embodiment [Figure 11] A skeleton diagram of the vehicle drive device according to the third embodiment [Figure 12] An axial cross-sectional view of the vehicle drive device according to the fourth embodiment [Figure 13] A skeleton diagram of the vehicle drive device according to the fourth embodiment [Figure 14] A cross-sectional view along the axial direction of a vehicle drive system according to the fifth embodiment. [Figure 15] A cross-sectional view along the axial direction of a vehicle drive system according to the sixth embodiment. [Modes for carrying out the invention]

[0013] 1. First Embodiment In the following description, the vehicle drive system 100 according to the first embodiment will be explained with reference to Figures 1 to 5.

[0014] As shown in Figures 1 and 2, the vehicle drive unit 100 includes an input member 2 driven and connected to a first drive source 1, a first output member 31 driven and connected to a first wheel W1 (see Figure 2), a second output member 32 arranged coaxially with the first output member 31 and driven and connected to a second wheel W2 (see Figure 2), a first planetary gear mechanism 4 that distributes the torque transmitted from the first drive source 1 to the input member 2 to the first output member 31 and the second output member 32, a second planetary gear mechanism 52 and a third planetary gear mechanism 53.

[0015] In this embodiment, the vehicle drive unit 100 further includes a transmission 6 that changes the speed of the rotation of the first drive source 1 and transmits it to the input member 2, and a first engagement device CL1 that selectively engages the first rotating member RM1 and the non-rotating member NR.

[0016] Herein, in this application, "drive connection" refers to a state in which two rotating elements are connected in a manner that can transmit driving force, and includes a state in which the two rotating elements are connected so as to rotate as a whole, or a state in which the two rotating elements are connected in a manner that can transmit 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 shafts, gear mechanisms, belts, chains, etc. Furthermore, the transmission members may also include engagement devices that selectively transmit rotation and driving force, such as friction engagement devices and meshing engagement devices. However, when referring to "drive connection" for each rotating element of a planetary gear mechanism, it refers to a state in which multiple rotating elements in the planetary gear mechanism are connected to each other without the need for other rotating elements.

[0017] In the following explanation, the direction along the rotational axes of the first output member 31 and the second output member 32 will be referred to as "axial direction L". One side of axial direction L will be referred to as "first axial direction L1", and the other side of axial direction L will be referred to as "second axial direction L2". The direction perpendicular to axial direction L will be referred to as "radial direction R". Radial direction R is defined with respect to the rotational axes of the rotating members such as the first output member 31 and the second output member 32. Note that if it is not necessary to distinguish which rotational axis is being referred to, or if it is clear which rotational axis is being referred to, it may simply be written as "radial direction R".

[0018] The first drive source 1 is a device that outputs driving force to drive the first wheel W1 and the second wheel W2. In this embodiment, the first drive source 1 is a first rotating electric machine MG1 equipped with a first stator ST1 and a first rotor RT1. In this embodiment, the first rotating electric machine MG1 is housed in a first case member 91 which is a non-rotating member NR.

[0019] The first rotating electric machine MG1 has the function of a motor that generates power when power is supplied, and the function of a generator that generates power when power is supplied. Specifically, the first rotating electric machine MG1 is electrically connected to an energy storage device such as a battery or capacitor (not shown in the diagram). The first rotating electric machine MG1 then generates driving force by moving using the power stored in the energy storage device. In addition, the first rotating electric machine MG1 generates electricity using the driving force transmitted from the first wheel W1 and the second wheel W2 to charge the energy storage device.

[0020] The first stator ST1 is fixed to a non-rotating member NR (here, the first case member 91). The first rotor RT1 is rotatably supported relative to the first stator ST1. In this embodiment, the first rotor RT1 is positioned radially inward R relative to the first stator ST1.

[0021] The first rotor RT1 is connected to the first rotating member RM1 so as to rotate integrally with it. In this embodiment, the first rotor RT1 is connected to the rotor shaft RS which extends along the axial direction L so as to rotate integrally with it. The rotor shaft RS is connected to the first rotating member RM1 so as to rotate integrally with it. In this embodiment, the first rotating member RM1 is positioned on the first shaft X1, which is the rotation axis of the first rotor RT1. The first axial end L1 of the first rotating member RM1 and the second axial end L2 of the rotor shaft RS are connected to each other.

[0022] The first engagement device CL1 is configured to be switchable between an engaged state in which the first rotating member RM1 is unable to rotate relative to the non-rotating member NR, and a released state in which the first rotating member RM1 is able to rotate relative to the non-rotating member NR. When the first engagement device CL1 is engaged, the first rotor RT1 becomes unable to rotate relative to the non-rotating member NR via the first rotating member RM1. Therefore, the first engagement device CL1 functions as a braking device that brakes the rotation of the first wheel W1 and the second wheel W2.

[0023] In this embodiment, the first engagement device CL1 is a friction engagement device equipped with a friction engagement element. The first engagement device CL1 includes a first pressing member PS1 that presses the friction engagement element and a first drive device DR1 that drives the first pressing member PS1. In this example, the rotational driving force of the first drive device DR1 is converted into an axial driving force L by a ball screw mechanism and transmitted to the first pressing member PS1. As a result, the first pressing member PS1 moves in the axial direction L. In this embodiment, the friction engagement element and the first pressing member PS1 of the first engagement device CL1 are housed in a second case member 92 which is a non-rotating member NR. The first drive device DR1 is positioned radially outward R relative to the second case member 92.

[0024] In this embodiment, the transmission 6 includes a transmission input shaft 61, a counter gear mechanism 62, a first gear G1, and a second gear G2. In this embodiment, the transmission input shaft 61 and the first gear G1 are arranged on a first shaft X1. The counter gear mechanism 62 is arranged on a second shaft X2, which is different from the first shaft X1. The second gear G2 is arranged on a third shaft X3, which is different from the first shaft X1 and the second shaft X2.

[0025] The gear shift input shaft 61 is a shaft member formed to extend along the axial direction L. The gear shift input shaft 61 is connected to the first rotor RT1 so as to rotate integrally with it. In this embodiment, the gear shift input shaft 61 is positioned on the first axial side L1 with respect to the rotor shaft RS. The end of the gear shift input shaft 61 on the second axial side L2 and the end of the rotor shaft RS on the first axial side L1 are connected to each other. The gear shift input shaft 61 is also connected to the first gear G1 so as to rotate integrally with it.

[0026] The counter gear mechanism 62 includes a third gear G3 and a fourth gear G4 that are connected to rotate integrally with each other. The third gear G3 meshes with the first gear G1. The fourth gear G4 meshes with the second gear G2. In this embodiment, the fourth gear G4 is positioned axially second L2 further than the third gear G3.

[0027] In this embodiment, the third gear G3 is formed with a larger diameter than the first gear G1. Furthermore, the second gear G2 is formed with a larger diameter than the fourth gear G4, which rotates integrally with the third gear G3. Therefore, in this embodiment, the rotation of the speed-shifting input shaft 61, which rotates integrally with the first rotor RT1, is reduced in speed by the power transmission path connecting the first gear G1 and the second gear G2, and then transmitted to the input member 2. In other words, in this embodiment, the transmission 6 is a fixed-ratio transmission (reduction unit) that changes the rotation of the first rotor RT1 at a constant gear ratio. In this embodiment, the second gear G2 corresponds to the input member 2.

[0028] The first planetary gear mechanism 4 functions as an output differential gear mechanism. The first planetary gear mechanism 4 is a double pinion type planetary gear mechanism comprising a first sun gear S1, a first carrier C1, and a first ring gear R1. In this embodiment, the first planetary gear mechanism 4 is located on the third shaft X3.

[0029] The first carrier C1 rotatably supports an inner pinion gear P11 and an outer pinion gear P12 that mesh with each other. Each of the inner pinion gear P11 and the outer pinion gear P12 rotates (rotates) around its axis and also revolves (orbits) around the first sun gear S1 together with the first carrier C1. Multiple inner pinion gears P11 and outer pinion gears P12 are provided at intervals from each other along their orbital trajectories.

[0030] The inner pinion gear P11 meshes with the first sun gear S1. The outer pinion gear P12 meshes with the first ring gear R1.

[0031] The first ring gear R1 is connected to the input member 2 (in this case, the second gear G2) so as to rotate integrally with it. In this embodiment, the first ring gear R1 is positioned radially inward of the second gear G2 in the radial direction R. Furthermore, the first ring gear R1 is positioned so as to overlap with the second gear G2 in a radial view along the radial direction R. Here, regarding the arrangement of the two elements, "overlapping in a specific direction view" means that when a virtual line parallel to the line of sight is moved in each direction perpendicular to the virtual line, there exists at least a portion of the region where the virtual line intersects both elements.

[0032] The first sun gear S1 is connected to the first output member 31 so as to rotate integrally with it. In this embodiment, the first output member 31 is positioned to extend from the first sun gear S1 in the axial direction L1. The first output member 31 is connected to the first wheel W1 so as to rotate integrally with it via the first drive shaft DS1 (see Figure 2), which extends in the axial direction L. In this embodiment, the first output member 31 is positioned on the third shaft X3.

[0033] The first carrier C1 is connected to the second output member 32 so as to rotate integrally with it. In this embodiment, the second output member 32 is positioned to extend from the first carrier C1 in the axial direction second L2. The second output member 32 is connected to the second wheel W2 so as to rotate integrally with it via a second drive shaft DS2 (see Figure 2) which extends in the axial direction L. In this embodiment, the second output member 32 is positioned on the third shaft X3.

[0034] As shown in Figure 3, the second planetary gear mechanism 52 is positioned adjacent to the first planetary gear mechanism 4 on the first axial side L1. The second planetary gear mechanism 52 is a single-pinion type planetary gear mechanism comprising a second sun gear S2, a second carrier C2, and a second ring gear R2. In this embodiment, the second planetary gear mechanism 52 is positioned on the third axis X3.

[0035] The second carrier C2 is connected to the first carrier C1 of the first planetary gear mechanism 4 so as to rotate integrally with it. The second carrier C2 rotatably supports the second pinion gear P2, which meshes with the second sun gear S2 and the second ring gear R2. The second pinion gear P2 rotates (rotates) around its axis and also revolves (orbits) around the second sun gear S2 together with the second carrier C2. Multiple second pinion gears P2 are provided spaced apart from each other along their orbital trajectory.

[0036] The third planetary gear mechanism 53 is positioned adjacent to the second planetary gear mechanism 52 on the first axial side L1. The third planetary gear mechanism 53 is a single-pinion type planetary gear mechanism comprising a third sun gear S3, a third carrier C3, and a third ring gear R3. In this embodiment, the third planetary gear mechanism 53 is positioned on the third shaft X3.

[0037] The third carrier C3 is connected to the first ring gear R1 of the first planetary gear mechanism 4 so as to rotate integrally with it. The third carrier C3 rotatably supports the third pinion gear P3, which meshes with the third sun gear S3 and the third ring gear R3. The third pinion gear P3 rotates (rotates) around its axis and also revolves (orbits) around the third sun gear S3 together with the third carrier C3. Multiple third pinion gears P3 are provided spaced apart from each other along their orbital trajectory.

[0038] The number of teeth of the second sun gear S2 and the third sun gear S3 are set to be the same. Similarly, the number of teeth of the second ring gear R2 and the third ring gear R3 are set to be the same. Furthermore, the number of teeth of the second pinion gear P2 and the third pinion gear P3 are set to be the same. Thus, the second planetary gear mechanism 52 and the third planetary gear mechanism 53 have the same number of teeth on their respective gears.

[0039] The second ring gear R2 and the third ring gear R3 are connected so that they rotate integrally with each other. In the illustrated example, the second ring gear R2 and the third ring gear R3 are formed integrally with each other. To elaborate, the second ring gear R2 and the third ring gear R3 are formed on the inner circumferential surface of a cylindrical member along the axial direction L, at positions separated from each other in the axial direction L.

[0040] In the following explanation, one of the second sun gear S2 and the third sun gear S3 will be referred to as the "driven sun gear Sd," and the other as the "fixed sun gear Sf."

[0041] As shown in Figure 3, the vehicle drive system 100 further includes a torque control device 5. The torque control device 5 is a device that controls the torque transmitted to the driven sun gear Sd.

[0042] The driven sun gear Sd is driven and connected to the torque control device 5. In this embodiment, the driven sun gear Sd is the second sun gear S2.

[0043] The fixed sun gear Sf is fixed to the non-rotating member NR. In this embodiment, the fixed sun gear Sf is the third sun gear S3. The third sun gear S3 is fixed to the third case member 93, which is the non-rotating member NR. The third case member 93 is formed to house a part of the first output member 31, a part of the second output member 32, the first planetary gear mechanism 4, the second planetary gear mechanism 52, the third planetary gear mechanism 53, and the transmission 6.

[0044] As described above, the vehicle drive system 100 is An input member 2 is connected to the first drive source 1, A first output member 31 is driven and connected to the first wheel W1, A second output member 32 is arranged coaxially with the first output member 31 and is driven and connected to the second wheel W2, A first planetary gear mechanism 4 distributes the torque transmitted from the first drive source 1 to the input member 2 to the first output member 31 and the second output member 32, The second planetary gear mechanism 52, A vehicle drive system 100 comprising a third planetary gear mechanism 53, The first planetary gear mechanism 4 is a double pinion type planetary gear mechanism comprising a first sun gear S1, a first carrier C1, and a first ring gear R1. The first ring gear R1 is connected to the input member 2 so as to rotate integrally with it. The first sun gear S1 is connected to the first output member 31 so as to rotate integrally with it. The first carrier C1 is connected to the second output member 32 so as to rotate integrally with it. The second planetary gear mechanism 52 is a single-pinion type planetary gear mechanism comprising a second sun gear S2, a second carrier C2, and a second ring gear R2, and is positioned adjacent to the first axial side L1 relative to the first planetary gear mechanism 4. The third planetary gear mechanism 53 is a single-pinion type planetary gear mechanism comprising a third sun gear S3, a third carrier C3, and a third ring gear R3, and is positioned adjacent to the second planetary gear mechanism 52 on the first axial side L1. The number of teeth of the second sun gear S2 and the number of teeth of the third sun gear S3 are the same. The number of teeth on the second ring gear R2 and the number of teeth on the third ring gear R3 are the same. The second ring gear R2 and the third ring gear R3 are connected so as to rotate integrally with each other. A driven sun gear Sd, which is either the second sun gear S2 or the third sun gear S3, is driven and connected to a torque control device 5 that controls the torque transmitted to the driven sun gear Sd. A fixed sun gear Sf, which is either the second sun gear S2 or the third sun gear S3, is fixed to the non-rotating member NR. The first carrier C1 and the second carrier C2 are connected so as to rotate integrally with each other. The first ring gear R1 and the third carrier C3 are connected so that they rotate integrally with each other.

[0045] With this configuration, if a drive source capable of transmitting torque in both the forward and negative rotation directions to the driven sun gear Sd is used as the torque control device 5, the second planetary gear mechanism 52 and the third planetary gear mechanism 53 can function as torque vectoring devices that transmit different torques to the first output member 31 and the second output member 32. Furthermore, if a device capable of transmitting reaction torque to the driven sun gear Sd is used as the torque control device 5, the second planetary gear mechanism 52 and the third planetary gear mechanism 53 can function as differential limiting devices that limit the differential function of the first planetary gear mechanism 4. Furthermore, in this configuration, the driven sun gear Sd is an input element driven and connected to the torque control device 5, while the fixed sun gear Sf is fixed to the non-rotating member NR. The second carrier C2 and the third carrier C3 are output elements connected to the first carrier C1 and the first ring gear R1 of the first planetary gear mechanism 4, respectively. This makes it easier to secure a large reduction ratio (specifically, the reduction ratio from the input element to the output element) for the second planetary gear mechanism 52 and the third planetary gear mechanism 53, which can function as a torque vectoring device or a differential limiting device, and to effectively transmit the torque of the torque control device 5 to the wheels W1 and W2. Therefore, it is easier to miniaturize the torque control device 5, and consequently the vehicle drive device 100. Furthermore, in this configuration, the first planetary gear mechanism 4 and the second planetary gear mechanism 52 are arranged adjacent to each other in the axial direction L. The first carrier C1 of the first planetary gear mechanism 4 and the second carrier C2 of the second planetary gear mechanism 52 are connected so as to rotate integrally with each other. This makes it easier to miniaturize the connection structure between the first carrier C1 and the second carrier C2, and consequently, the vehicle drive unit 100. As described above, this configuration makes it easier to miniaturize the vehicle drive unit 100 while ensuring a large reduction ratio for the second planetary gear mechanism 52 and the third planetary gear mechanism 53.

[0046] In this embodiment, a portion of the first carrier C1 and a portion of the second carrier C2 are shared. In the example shown in Figure 3, a portion of the first carrier C1 located axially first L1 further than the inner pinion gear P11 and the outer pinion gear P12 is shared with a portion of the second carrier C2 located axially second L2 further than the second pinion gear P2.

[0047] This configuration makes it even easier to miniaturize the connecting structure between the first carrier C1 and the second carrier C2.

[0048] In this embodiment, the vehicle drive unit 100 further includes a case member 7 configured to rotate integrally with the input member 2, the first ring gear R1, and the third carrier C3. The case member 7 is formed to cover the radially outer R of the first planetary gear mechanism 4, the second planetary gear mechanism 52, and the third planetary gear mechanism 53. In the example shown in Figure 3, the first ring gear R1 is formed on the inner circumferential surface of the case member 7, and the second gear G2, which serves as the input member 2, is formed on the outer circumferential surface of the case member 7. Furthermore, the portion of the third carrier C3 located axially first L1 relative to the third pinion gear P3 is integrally formed with the case member 7.

[0049] With this configuration, the first planetary gear mechanism 4 for distributing driving force to the first output member 31 and the second output member 32, and the second planetary gear mechanism 52 and the third planetary gear mechanism 53 can be housed inside the radial radius R of the case member 7. This makes it easier to miniaturize the vehicle drive unit 100. Furthermore, since the case member 7, the first planetary gear mechanism 4, the second planetary gear mechanism 52, and the third planetary gear mechanism 53 can be modularized, the manufacturing process of the vehicle drive unit 100 can be simplified.

[0050] As shown in Figure 3, in this embodiment, the torque control device 5 is equipped with a second drive source 51.

[0051] The second drive source 51 is a device for applying both the torque on one side of the rotational direction of the driven sun gear Sd and the torque on the other side of the rotational direction to the driven sun gear Sd. In this embodiment, the second drive source 51 is a second rotating electric machine MG2 equipped with a second stator ST2 and a second rotor RT2 (see Figure 2). The second stator ST2 is fixed to a non-rotating member NR (for example, a case housing the second rotating electric machine MG2). The second rotor RT2 is rotatably supported relative to the second stator ST2.

[0052] The second rotating electric machine MG2 has at least the function of a motor that generates power when power is supplied. The second rotating electric machine MG2 may also have the function of a generator that generates power when power is supplied. In this embodiment, the second rotating electric machine MG2 is located on a fourth axis X4, which is different from the first axis X1, the second axis X2, and the third axis X3.

[0053] Thus, in this embodiment, the torque control device 5 includes a second drive source 51 for applying both the torque on one side of the rotational direction of the driven sun gear Sd and the torque on the other side of the rotational direction to the driven sun gear Sd.

[0054] With this configuration, the second planetary gear mechanism 52 and the third planetary gear mechanism 53 can function as torque vectoring devices that transmit different torques to the first output member 31 and the second output member 32.

[0055] As shown in Figure 3, in this embodiment, the torque control device 5 further includes a power transmission mechanism 54 that transmits the driving force of the second drive source 51 to the driven sun gear Sd. The power transmission mechanism 54 includes a fifth gear G5 and a sixth gear G6. In this embodiment, the fifth gear G5 is located on the third shaft X3. The sixth gear G6 is located on the fourth shaft X4.

[0056] The fifth gear G5 is a "driven gear" connected to the driven sun gear Sd so as to rotate integrally with it. The fifth gear G5 is formed with a larger diameter than the second ring gear R2 and the third ring gear R3. In the illustrated example, the fifth gear G5 has an outer diameter that overlaps with that of the third gear G3 of the counter gear mechanism 62 when viewed axially along the axial direction L.

[0057] The sixth gear G6 is a "drive gear" that meshes with the fifth gear G5 and is driven by the second drive source 51. The sixth gear G6 is formed to have a smaller diameter than the fifth gear G5. In this embodiment, the sixth gear G6 is connected to the second rotor RT2 (see Figure 2) of the second rotating electric machine MG2, which is the second drive source 51, so as to rotate integrally with it.

[0058] Thus, in this embodiment, the torque control device 5 further includes a power transmission mechanism 54 that transmits the driving force of the second drive source 51 to the driven sun gear Sd. The power transmission mechanism 54 includes a fifth gear G5 as a driven gear connected to the driven sun gear Sd so as to rotate integrally with it, and a sixth gear G6 as a drive gear that meshes with the fifth gear G5 and is driven by the second drive source 51. The fifth gear G5 has a larger diameter than the second ring gear R2 and the third ring gear R3. The sixth gear G6 has a smaller diameter than the fifth gear G5.

[0059] In this configuration, the fifth gear G5, which acts as a large-diameter driven gear, is connected to the driven sun gear Sd so as to rotate integrally with it. The sixth gear G6, which acts as a small-diameter drive gear that meshes with the fifth gear G5, is driven by the second drive source 51. As a result, the driving force of the second drive source 51 can be amplified between the drive gear and driven gear constituting the power transmission mechanism 54 and transmitted to the driven sun gear Sd. Therefore, it is easier to miniaturize the second drive source 51, and consequently the vehicle drive system 100.

[0060] As shown in Figure 3, in this embodiment, the vehicle drive unit 100 further comprises a first connecting shaft 55 and a second connecting shaft 56.

[0061] The first connecting shaft 55 is a shaft member for connecting the second sun gear S2 to either the torque control device 5 or the non-rotating member NR. In this embodiment, the first connecting shaft 55 is positioned to extend from the second sun gear S2 in the first axial direction L1. The first connecting shaft 55 connects the second sun gear S2 and the fifth gear G5 of the power transmission mechanism 54 in the torque control device 5 so that they rotate together. In this embodiment, the first connecting shaft 55 is formed in a cylindrical shape that covers the outside of the radial direction R of the first output member 31, which is positioned to extend from the first sun gear S1 in the first axial direction L1. Thus, in this embodiment, the first connecting shaft 55 is positioned radially R further out than the first output member 31.

[0062] As described above, in this embodiment, the first output member 31 is arranged to extend from the first sun gear S1 in the first axial direction L1, and the second output member 32 is arranged to extend from the first carrier C1 in the second axial direction L2. However, it is also possible to have a configuration in which the first output member 31 extends from the first sun gear S1 in the second axial direction L2, and the second output member 32 extends from the first carrier C1 in the first axial direction L1 (see the second to sixth embodiments described later). In other words, the first output member 31 and the second output member 32 are arranged to extend in opposite directions in the axial direction L. In a configuration where the first output member 31 is arranged to extend from the first sun gear S1 in the second axial direction L2, and the second output member 32 is arranged to extend from the first carrier C1 in the first axial direction L1, it is preferable that the first connecting shaft 55 is formed in a cylindrical shape that covers the outside of the second output member 32 in the radial direction R, that is, the first connecting shaft 55 is arranged to be outside the second output member 32 in the radial direction R.

[0063] The second connecting shaft 56 is a shaft member for connecting the third sun gear S3 to either the torque control device 5 or the non-rotating member NR. In this embodiment, the second connecting shaft 56 is positioned to extend from the third sun gear S3 in the axial direction first L1. The second connecting shaft 56 connects the third sun gear S3 to the third case member 93, which is the non-rotating member NR, so that the third sun gear S3 is fixed to it. In this embodiment, the second connecting shaft 56 is formed in a cylindrical shape that covers the outside of the first connecting shaft 55 in the radial direction R. Thus, the second connecting shaft 56 is positioned radially outside the first connecting shaft 55.

[0064] Thus, in this embodiment, the first output member 31 and the second output member 32 are arranged to extend in opposite directions in the axial direction L. A first connecting shaft 55 for connecting the second sun gear S2 to either the torque control device 5 or the non-rotating member NR is arranged to extend from the second sun gear S2 in the axial direction to the first side L1. A second connecting shaft 56 for connecting the third sun gear S3 to either the torque control device 5 or the non-rotating member NR is arranged to extend from the third sun gear S3 in the axial direction to the first side L1. The first connecting shaft 55 is positioned radially R outward from the first output member 31 or the second output member 32. The second connecting shaft 56 is positioned radially outward R than the first connecting shaft 55.

[0065] With this configuration, the second sun gear S2 and the first connecting shaft 55 for connecting either the torque control device 5 or the non-rotating member NR, and the third sun gear S3 and the second connecting shaft 56 for connecting either the torque control device 5 or the non-rotating member NR, can be arranged linearly along the axial direction L, and can be arranged overlapping the radially outside R of the first output member 31 or the second output member 32. This makes it easier to keep the space required for the first connecting shaft 55 and the second connecting shaft 56 small. As a result, it is easier to miniaturize the vehicle drive unit 100.

[0066] Figures 4 and 5 show the velocity diagrams of the first planetary gear mechanism 4, the second planetary gear mechanism 52, and the third planetary gear mechanism 53 according to this embodiment. The velocity diagram in Figure 4 will be described below, but the same applies to the velocity diagram in Figure 5.

[0067] The diagram shown on the left side of Figure 4 is a velocity diagram of the first planetary gear mechanism 4. In the velocity diagram of the first planetary gear mechanism 4, the position on the vertical line corresponds to the rotational speed of each rotating element of the first planetary gear mechanism 4. Each of the multiple vertical lines arranged in parallel corresponds to each rotating element of the first planetary gear mechanism 4. In the velocity diagram of the first planetary gear mechanism 4, the symbols shown above the multiple vertical lines are the symbols of the rotating elements of the first planetary gear mechanism 4. The symbols shown below the multiple vertical lines are the symbols of the elements driven and connected to the rotating elements corresponding to the symbols shown above.

[0068] The diagram on the right side of Figure 4 shows the velocity diagrams of the second planetary gear mechanism 52 and the third planetary gear mechanism 53. In the diagram on the right side of Figure 4, the velocity diagram of the second planetary gear mechanism 52 is shown with a solid line, and the velocity diagram of the third planetary gear mechanism 53 is shown with a dashed line. In the velocity diagrams of the second planetary gear mechanism 52 and the third planetary gear mechanism 53, the position on the vertical line corresponds to the rotational speed of each rotating element of the second planetary gear mechanism 52 and the third planetary gear mechanism 53. Each of the multiple vertical lines arranged in parallel corresponds to each rotating element of the second planetary gear mechanism 52 and the third planetary gear mechanism 53. In the velocity diagrams of the second planetary gear mechanism 52 and the third planetary gear mechanism 53, the upper symbols shown above the multiple vertical lines are the symbols for the rotating elements of the second planetary gear mechanism 52. The lower symbols shown above the multiple vertical lines are the symbols for the rotating elements of the third planetary gear mechanism 53. Furthermore, the upper symbols shown below the multiple vertical lines are the symbols of elements driven and connected to the rotating elements corresponding to the symbols of the rotating elements of the second planetary gear mechanism 52 shown above. And the lower symbols shown below the multiple vertical lines are the symbols of elements driven and connected to the rotating elements corresponding to the symbols of the rotating elements of the third planetary gear mechanism 53 shown above.

[0069] In Figure 4, the black dots on the vertical lines in both the left and right diagrams indicate that the rotation elements corresponding to the vertical lines rotate as a single unit. The same applies to the white dots on the vertical lines. The cross marks on the vertical lines indicate that the rotation elements corresponding to the vertical lines are fixed to the non-rotating member NR.

[0070] Figure 4 shows an example of a speed diagram when a vehicle equipped with a vehicle drive unit 100 is turning with the first wheel W1 as the inner wheel. As shown in Figure 4, when the forward rotation torque (upward in Figure 4) of the second rotating electric machine MG2, which is the second drive source 51 (see shaded arrow in Figure 4), is transmitted to the second sun gear S2, that torque is transmitted to the second carrier C2. Here, the second ring gear R2 and the third ring gear R3 are connected so as to rotate integrally with each other. The third sun gear S3 is fixed to the non-rotating member NR. Therefore, the forward rotation torque of the second rotating electric machine MG2 transmitted to the second sun gear S2 acts as a forward rotation torque on the second carrier C2 (see black arrow in Figure 4) and as a reverse rotation torque (downward in Figure 4) on the third carrier C3 (see white arrow in Figure 4).

[0071] The second carrier C2 is connected to the first carrier C1 of the first planetary gear mechanism 4 so as to rotate integrally with it, and the third carrier C3 is connected to the first ring gear R1 of the first planetary gear mechanism 4 so as to rotate integrally with it. Therefore, the reverse torque transmitted from the third carrier C3 to the first ring gear R1 is a torque in the opposite direction to the forward torque transmitted from the first rotating electric machine MG1 to the first ring gear R1. As a result, a smaller torque is distributed to the first carrier C1 and the first sun gear S1 of the first planetary gear mechanism 4 than the torque transmitted from the first rotating electric machine MG1 to the first ring gear R1. Also, the forward torque transmitted from the second carrier C2 to the first carrier C1 is a torque in the same direction as the forward torque transmitted from the first rotating electric machine MG1 to the first carrier C1 via the first planetary gear mechanism 4. As a result, the torque transmitted to the first carrier C1 becomes relatively larger than the torque transmitted to the first sun gear S1. This creates a difference in the torque transmitted to the first wheel W1, which is connected to the first sun gear S1 via the first output member 31 to rotate integrally with it, and the second wheel W2, which is connected to the first carrier C1 via the second output member 32 to rotate integrally with it, thereby realizing torque vectoring. In this case, the first wheel W1 is relatively decelerated and the second wheel W2 is relatively accelerated. Thus, in this embodiment, the second planetary gear mechanism 52 and the third planetary gear mechanism 53 function as torque vectoring devices that cause the torque transmitted to the first output member 31 and the second output member 32 to differ.

[0072] Figure 5 shows an example of a speed diagram when a vehicle equipped with a vehicle drive system 100 is turning with the second wheel W2 as the inner wheel. Although details are omitted, in this case, when the torque in the reverse direction of the second rotating electric machine MG2, which is the second drive source 51, is transmitted to the second sun gear S2, the torque transmitted to the first carrier C1 becomes relatively smaller than the torque transmitted to the first sun gear S1.

[0073] 2. Second Embodiment The vehicle drive system 100 according to the second embodiment will be described below with reference to Figures 6 to 9. In this embodiment, the configuration of the transmission 6 and the first planetary gear mechanism 4 differs from that of the vehicle drive system 100 according to the first embodiment. The following description will focus on the differences from the first embodiment. Unless otherwise specified, the same applies as in the first embodiment.

[0074] As shown in Figures 6 and 7, in this embodiment, the transmission 6 does not have a counter gear mechanism 62 and a first gear G1, but has a fourth planetary gear mechanism 63, a second engagement device CL2, a seventh gear G7, and an eighth gear G8. In this embodiment, the fourth planetary gear mechanism 63, the second engagement device CL2, and the seventh gear G7 are arranged on the first shaft X1. The eighth gear G8 is arranged on the second shaft X2.

[0075] The fourth planetary gear mechanism 63 is a single-pinion type planetary gear mechanism comprising a fourth sun gear S4, a fourth carrier C4, and a fourth ring gear R4.

[0076] The fourth sun gear S4 is connected to the speed input shaft 61 so as to rotate integrally with it. The fourth carrier C4 is connected to the seventh gear G7 so as to rotate integrally with it. The fourth carrier C4 also rotatably supports the fourth pinion gear P4, which meshes with the fourth sun gear S4 and the fourth ring gear R4. The fourth pinion gear P4 rotates (rotates) around its axis and also revolves (orbits) around the fourth sun gear S4 together with the fourth carrier C4. Multiple fourth pinion gears P4 are provided spaced apart from each other along their orbital trajectory.

[0077] The second engagement device CL2 is configured to switch the reduction ratio of the transmission 6 according to the engagement state. In this embodiment, the second engagement device CL2 includes a clutch mechanism C and a brake mechanism B. The second engagement device CL2 is configured such that when one of the clutch mechanism C and the brake mechanism B is engaged, the other is released.

[0078] The clutch mechanism C is configured to selectively engage a second rotating member RM2 and a third rotating member RM3, which are supported to rotate relative to each other. The brake mechanism B is configured to selectively engage a second rotating member RM2 and a non-rotating member NR (in this case, a fourth case member 94).

[0079] In this embodiment, the clutch mechanism C and the brake mechanism B are each friction engagement devices equipped with friction engagement elements. In this embodiment, the second engagement device CL2 includes a second pressing member PS2 that presses the respective friction engagement elements of the clutch mechanism C and the brake mechanism B, and a second drive device DR2 (see Figure 9) that drives the second pressing member PS2. In this example, the second pressing member PS2 is positioned between the friction engagement elements of the clutch mechanism C and the friction engagement elements of the brake mechanism B in the axial direction L. The rotational driving force of the second drive device DR2 is converted into an axial driving force L by a ball screw mechanism and transmitted to the second pressing member PS2. As a result, the second pressing member PS2 moves in the axial direction L and presses either the friction engagement element of the clutch mechanism C or the friction engagement element of the brake mechanism B. In this embodiment, the clutch mechanism C and the brake mechanism B are housed in a fourth case member 94, which is a non-rotating member NR. Although not shown in the diagram, the second drive unit DR2 is positioned radially outward from the fourth case member 94 in the direction R.

[0080] The second rotating member RM2 is connected to the fourth ring gear R4 of the fourth planetary gear mechanism 63 so as to rotate integrally with it. In this embodiment, the second rotating member RM2 is formed in a cylindrical shape that covers the radially outer side R of the third rotating member RM3.

[0081] The third rotating member RM3 is connected to the speed input shaft 61 so as to rotate integrally with it. In this embodiment, the third rotating member RM3 is positioned on the first axial side L1 with respect to the speed input shaft 61.

[0082] When the clutch mechanism C is engaged and the brake mechanism B is released, the fourth ring gear R4 connected to the second rotating member RM2, the fourth carrier C4 connected to the seventh gear G7, and the fourth sun gear S4 connected to the third rotating member RM3 via the speed shift input shaft 61 rotate together as a single unit. As a result, the rotation of the first rotor RT1 is not reduced and is transmitted directly to the seventh gear G7.

[0083] On the other hand, when the clutch mechanism C is disengaged and the brake mechanism B is engaged, the fourth ring gear R4 connected to the second rotating member RM2 is fixed to the non-rotating member NR, and the fourth carrier C4 connected to the seventh gear G7 and the fourth sun gear S4 connected to the third rotating member RM3 via the speed shift input shaft 61 rotate relative to each other. As a result, the rotation of the first rotor RT1 is reduced in the fourth planetary gear mechanism 63 and transmitted to the seventh gear G7.

[0084] The seventh gear G7 meshes with the eighth gear G8. The eighth gear G8 is an idler gear that meshes with the second gear G2. In other words, the seventh gear G7 and the second gear G2 mesh with the eighth gear G8 at different positions in the circumferential direction of the eighth gear G8.

[0085] In this embodiment, the seventh gear G7 is formed with a smaller diameter than the second gear G2. Therefore, in this embodiment, the rotation of the fourth carrier C4 of the fourth planetary gear mechanism 63 is reduced in the power transmission path connecting the seventh gear G7 and the second gear G2 and transmitted to the input member 2.

[0086] As shown in Figure 8, in this embodiment, the first output member 31 is arranged to extend from the first sun gear S1 in the axial direction to the second side L2. The first output member 31 is connected to the first wheel W1 via the first drive shaft DS1 (see Figure 7) so as to rotate integrally with it.

[0087] Furthermore, in this embodiment, the second output member 32 is arranged to extend from the first carrier C1 in the axial direction to the first side L1. The second output member 32 is connected to the second wheel W2 via the second drive shaft DS2 (see Figure 7) so as to rotate integrally with it. In this embodiment, the first connecting shaft 55 is formed in a cylindrical shape that covers the outside of the second output member 32 in the radial direction R. Thus, in this embodiment, the first connecting shaft 55 is positioned radially R further out than the second output member 32.

[0088] Figure 9 shows the positional relationship of each element of the vehicle drive unit 100 in an axial view along the axial direction L. As shown in Figure 9, in this embodiment, the second drive unit DR2 of the second engagement device CL2 is located on a fifth axis X5, which is different from the first axis X1, second axis X2, third axis X3, and fourth axis X4. The second drive unit DR2 and the second rotating electric machine MG2 are located on opposite sides of a virtual plane S that includes the first axis X1 and the third axis X3. In addition, in this embodiment, the second drive unit DR2 and the second rotating electric machine MG2 are located so as to overlap with the first planetary gear mechanism 4 in an axial view along the axial direction L. With this configuration, the radial dimension R of the vehicle drive unit 100 can be kept small.

[0089] 3. Third Embodiment In the following description, the vehicle drive system 100 according to the third embodiment will be explained with reference to Figures 10 and 11. In this embodiment, the configuration of the torque control device 5 mainly differs from that of the vehicle drive system 100 according to the second embodiment. In the following description, the differences from the second embodiment will be explained in detail. Unless otherwise specified, the same applies as in the second embodiment.

[0090] As shown in Figures 10 and 11, in this embodiment, the torque control device 5 does not include a second drive source 51, but instead includes a first friction engagement device FE1.

[0091] The first friction engagement device FE1 is a device that selectively engages the first interlocking member CM1 with the non-rotating member NR. The first friction engagement device FE1 is configured to switch between an engaged state in which the first interlocking member CM1 is unable to rotate relative to the non-rotating member NR, and a released state in which the first interlocking member CM1 is able to rotate relative to the non-rotating member NR.

[0092] The first friction engagement device FE1 is a friction engagement device equipped with a friction engagement element. The first friction engagement device FE1 includes a third pressing member PS3 that presses the friction engagement element, and a third drive device (not shown) that drives the third pressing member PS3. In this example, the rotational driving force of the third drive device is converted into an axial driving force L by a trapezoidal screw mechanism and transmitted to the third pressing member PS3. As a result, the third pressing member PS3 moves in the axial direction L. In this embodiment, the friction engagement element and the third pressing member PS3 of the first friction engagement device FE1 are housed in a fifth case member 95, which is a non-rotating member NR.

[0093] The first interlocking member CM1 is a member that rotates in conjunction with the driven sun gear Sd. In this embodiment, the first interlocking member CM1 is connected to the tenth gear G10, which meshes with the ninth gear G9, so as to rotate integrally with it. The ninth gear G9 is connected to the third sun gear S3 so as to rotate integrally with it. Thus, in this embodiment, the third sun gear S3 is the driven sun gear Sd. On the other hand, the second sun gear S2 is the fixed sun gear Sf. In this embodiment, the second sun gear S2 is fixed to the third case member 93, which is a non-rotating member NR. In this embodiment, the tenth gear G10 is formed to have a smaller diameter than the ninth gear G9.

[0094] Furthermore, in this embodiment, the first interlocking member CM1 is positioned on a sixth axis X6 that is different from the first axis X1 to the fifth axis X5.

[0095] When the first friction engagement device FE1 is engaged, the relative rotation of the third sun gear S3, which acts as the driven sun gear Sd, with respect to the non-rotating member NR is restricted via the ninth gear G9 and the tenth gear G10. As a result, the difference in torque transmitted between the first wheel W1, which is connected to rotate integrally with the first sun gear S1 via the first output member 31, and the second wheel W2, which is connected to rotate integrally with the first carrier C1 via the second output member 32, becomes smaller. In other words, the reaction torque transmitted from the first friction engagement device FE1 to the third sun gear S3, which acts as the driven sun gear Sd, generates a force that brings the rotational speeds of the second carrier C2 and the third carrier C3 closer together, thereby generating a force that brings the rotational speeds of the first carrier C1 connected to the second carrier C2 and the first ring gear R1 connected to the third carrier C3 closer together (i.e., a force that limits the differential function of the first planetary gear mechanism 4). Thus, in this embodiment, the second planetary gear mechanism 52 and the third planetary gear mechanism 53 function as differential limiting devices that limit the differential function of the first planetary gear mechanism 4.

[0096] As described above, in this embodiment, the torque control device 5 is equipped with a first friction engagement device FE1 that selectively engages the first interlocking member CM1, which rotates in conjunction with the driven sun gear Sd, with the non-rotating member NR.

[0097] With this configuration, the second planetary gear mechanism 52 and the third planetary gear mechanism 53 can function as differential limiting devices that limit the differential function of the first planetary gear mechanism 4.

[0098] In this embodiment, the vehicle drive unit 100 does not include the first engagement device CL1.

[0099] 4. Fourth Embodiment In the following description, the vehicle drive unit 100 according to the fourth embodiment will be explained with reference to Figures 12 and 13. This embodiment differs from the third embodiment in that it includes a second friction engagement device FE2. The following description will focus on the differences from the third embodiment. Points that are not specifically described are the same as those in the third embodiment.

[0100] As shown in Figures 12 and 13, in this embodiment, the vehicle drive unit 100 is equipped with a second friction engagement device FE2.

[0101] The second friction engagement device FE2 is a device that selectively engages the second interlocking member CM2 with the non-rotating member NR. The second friction engagement device FE2 is configured to switch between an engaged state in which the second interlocking member CM2 is unable to rotate relative to the non-rotating member NR, and a released state in which the second interlocking member CM2 is able to rotate relative to the non-rotating member NR.

[0102] The second friction engagement device FE2 is a friction engagement device equipped with a friction engagement element. The second friction engagement device FE2 includes a fourth pressing member PS4 that presses the friction engagement element, and a fourth drive device (not shown) that drives the fourth pressing member PS4. In this example, the rotational driving force of the fourth drive device is converted into an axial driving force L by a trapezoidal screw mechanism and transmitted to the fourth pressing member PS4. As a result, the fourth pressing member PS4 moves in the axial direction L. In this embodiment, the friction engagement element and the fourth pressing member PS4 of the second friction engagement device FE2 are housed in a sixth case member 96, which is a non-rotating member NR.

[0103] The second interlocking member CM2 is a member that rotates in conjunction with any of the first sun gear S1, first carrier C1, first ring gear R1, and second ring gear R2, without going through the first planetary gear mechanism 4, the second planetary gear mechanism 52, and the third planetary gear mechanism 53. In this embodiment, the second interlocking member CM2 is connected to the 11th gear G11, which meshes with the second gear G2, so as to rotate integrally with it. The 11th gear G11 meshes with the second gear G2 at a position different from the 8th gear G8 in the circumferential direction of the second gear G2. Thus, in this embodiment, the second interlocking member CM2 rotates in conjunction with the first ring gear R1, which is connected to rotate integrally with the second gear G2, without going through the first planetary gear mechanism 4, the second planetary gear mechanism 52, and the third planetary gear mechanism 53.

[0104] When both the first friction engagement device FE1 and the second friction engagement device FE2 are engaged, the first wheel W1, which is connected to the first sun gear S1 via the first output member 31 to rotate integrally with it, and the second wheel W2, which is connected to the first carrier C1 via the second output member 32 to rotate integrally with it, are locked. In this way, the first friction engagement device FE1 and the second friction engagement device FE2 function as a parking brake.

[0105] As described above, in this embodiment, in a configuration equipped with the first friction engagement device FE1, The system further includes a second friction engagement device FE2 that selectively engages a second interlocking member CM2, which rotates in conjunction with any of the first sun gear S1, first carrier C1, first ring gear R1, and second ring gear R2, with a non-rotating member NR, without going through the first planetary gear mechanism 4, the second planetary gear mechanism 52, and the third planetary gear mechanism 53.

[0106] With this configuration, by engaging both the first friction engagement device FE1 and the second friction engagement device FE2, the first output member 31 and the second output member 32 can be locked to prevent rotation. Therefore, the need to provide a separate parking brake can be eliminated.

[0107] In this embodiment, the second interlocking member CM2 is positioned on the sixth axis X6. That is, in this embodiment, the first interlocking member CM1 and the second interlocking member CM2 are positioned coaxially. The first friction engagement device FE1 is positioned on the first axial side L1 relative to the third planetary gear mechanism 53. The second friction engagement device FE2 is positioned on the second axial side L2 relative to the first planetary gear mechanism 4. Furthermore, in an axial view along the axial direction L, both the first friction engagement device FE1 and the second friction engagement device FE2 overlap with at least one of the first planetary gear mechanism 4, the second planetary gear mechanism 52, and the third planetary gear mechanism 53. In the example shown in Figure 12, both the first friction engagement device FE1 and the second friction engagement device FE2 are positioned so as to overlap with all of the first planetary gear mechanism 4, the second planetary gear mechanism 52, and the third planetary gear mechanism 53 in an axial view along the axial direction L.

[0108] This configuration makes it easier to miniaturize the vehicle drive unit 100.

[0109] 5. Fifth Embodiment In the following description, a vehicle drive system 100 according to the fifth embodiment will be explained with reference to Figure 14. This embodiment differs from the fourth embodiment in that it transmits the rotation of the first drive source 1 to the input member 2 via the propeller shaft 8. The following description will focus on the differences from the fourth embodiment. Points that are not specifically described are the same as those in the fourth embodiment.

[0110] As shown in Figure 14, in this embodiment, the propeller shaft 8 is connected to rotate integrally with the 12th gear G12. The 12th gear G12 meshes with the 13th gear G13. The 13th gear G13 is connected to rotate integrally with the input member 2. In this embodiment, the 13th gear G13 is formed to have a larger diameter than the 12th gear G12. Also in this embodiment, the 12th gear G12 is a bevel gear having a rotation axis perpendicular to the axial direction L. The 13th gear G13 is a bevel gear arranged coaxially with the second gear G2, which is the input member 2. In the example shown in Figure 14, the 13th gear G13 is formed on the surface of the case member 7 facing the axial second side L2.

[0111] 6. Sixth Embodiment The vehicle drive unit 100 according to the sixth embodiment will be described below with reference to Figure 15. In this embodiment, the installation configuration of the second friction engagement device FE2 differs from that of the vehicle drive unit 100 according to the fifth embodiment. The following description will focus on the differences from the fifth embodiment. Points that are not specifically described are the same as those of the fifth embodiment.

[0112] As shown in Figure 15, in this embodiment, the second friction engagement device FE2 is positioned so as not to overlap with any of the first planetary gear mechanism 4, the second planetary gear mechanism 52, and the third planetary gear mechanism 53 in an axial view along the axial direction L. Furthermore, in this embodiment, the second friction engagement device FE2 is positioned such that its axial direction L positioning area overlaps with at least one of the axial direction L positioning areas of the first planetary gear mechanism 4, the second planetary gear mechanism 52, and the third planetary gear mechanism 53. In the example shown in Figure 15, the second friction engagement device FE2 is positioned radially R outward from the first planetary gear mechanism 4, the second planetary gear mechanism 52, and the third planetary gear mechanism 53 such that its axial direction L positioning area overlaps with the overall axial direction L positioning area of ​​the first planetary gear mechanism 4, the second planetary gear mechanism 52, and the third planetary gear mechanism 53.

[0113] Furthermore, in this embodiment, the second interlocking member CM2 is connected to the 15th gear G15, which meshes with the 14th gear G14, so as to rotate integrally with it. The 15th gear G15 is connected to the propeller shaft 8 so as to rotate integrally with it. In this embodiment, the 15th gear G15 is formed to have a smaller diameter than the 14th gear G14. Also, in this embodiment, the 14th gear G14 is arranged coaxially with the propeller shaft 8. The 15th gear G15 is positioned so that its rotation axis aligns with the rotation axis of the propeller shaft 8.

[0114] 7. Other Embodiments (1) In the above embodiment, the configuration in which the first drive source 1 is a first rotating electric machine MG1 equipped with a first stator ST1 and a first rotor RT1 was described as an example. However, the configuration is not limited to such an example, and the first drive source 1 may be an internal combustion engine.

[0115] (2) In the above embodiment, a configuration in which a part of the first carrier C1 and a part of the second carrier C2 are shared was described as an example. However, the invention is not limited to such a configuration, and for example, the first carrier C1 and the second carrier C2 may be made of separate components.

[0116] (3) In the above embodiment, the vehicle drive unit 100 was described as having a case member 7 configured to rotate integrally with the input member 2, the first ring gear R1, and the third carrier C3. However, the vehicle drive unit is not limited to such a configuration, and for example, the input member 2, the first ring gear R1, and the third carrier C3 may be connected to each other by bolts or the like so that they rotate integrally.

[0117] (4) In the first and second embodiments described above, the power transmission mechanism 54 was described as having a configuration comprising a fifth gear G5 as a driven gear and a sixth gear G6 as a drive gear driven by the second drive source 51. However, the configuration is not limited to such a configuration, and for example, another gear may be arranged in the power transmission path connecting the second drive source 51 and the sixth gear G6.

[0118] (5) In the fourth and fifth embodiments described above, a configuration in which the first interlocking member CM1 and the second interlocking member CM2 are arranged on the same axis was described as an example. However, the invention is not limited to such a configuration, and the first interlocking member CM1 and the second interlocking member CM2 may be arranged on different axes.

[0119] (6) In the fourth and fifth embodiments described above, the first friction engagement device FE1 is positioned on the first axial side L1 relative to the third planetary gear mechanism 53, and the second friction engagement device FE2 is positioned on the second axial side L2 relative to the first planetary gear mechanism 4, and a configuration has been described as being arranged such that both the first friction engagement device FE1 and the second friction engagement device FE2 overlap with at least one of the first planetary gear mechanism 4, the second planetary gear mechanism 52, and the third planetary gear mechanism 53 in an axial view along the axial direction L. However, the configuration is not limited to such a configuration, and for example, both the first friction engagement device FE1 and the second friction engagement device FE2 may be positioned on the first axial side L1 relative to the third planetary gear mechanism 53. In this case, it is preferable that the first friction engagement device FE1 and the second friction engagement device FE2 are arranged circumferentially with a gap between them on the radially outer side R of the second output member 32, so as to overlap with at least one of the first planetary gear mechanism 4, the second planetary gear mechanism 52, and the third planetary gear mechanism 53.

[0120] (7) The configurations disclosed in each of 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]

[0121] The technology disclosed herein can be used in a vehicle drive system comprising: an input member driven to a drive source; a first output member driven to a first wheel; a second output member driven to a second wheel; a first planetary gear mechanism that distributes torque transmitted from the drive source to the input member to the first and second output members; a second planetary gear mechanism; and a third planetary gear mechanism. [Explanation of Symbols]

[0122] 100: Vehicle drive unit, 1: First drive source, 2: Input member, 31: First output member, 32: Second output member, 4: First planetary gear mechanism, S1: First sun gear, C1: First carrier, R1: First ring gear, 5: Torque control device, 51: Second drive source, 52: Second planetary gear mechanism, S2: Second sun gear, C2: Second carrier, R2: Second ring gear, 53: Third planetary gear mechanism, S3: Third sun gear, C3: Third carrier, R3: Third ring gear, Sd: Driven sun gear, Sf: Fixed sun gear, NR: Non-rotating member, L: Axial direction, L1: First axial side, L2: Second axial side

Claims

1. An input member connected to the first drive source, A first output member is driven and connected to the first wheel, A second output member is arranged coaxially with the first output member and is driven and connected to the second wheel, A first planetary gear mechanism distributes the torque transmitted from the first drive source to the input member to the first output member and the second output member, The second planetary gear mechanism, A vehicle drive system comprising a third planetary gear mechanism, The direction along the rotation axis of the first output member and the second output member is defined as the axial direction, one side in the axial direction is defined as the first axial side, and the other side in the axial direction is defined as the second axial side. The first planetary gear mechanism is a double pinion type planetary gear mechanism comprising a first sun gear, a first carrier, and a first ring gear. The first ring gear is connected to the input member so as to rotate integrally with it. The first sun gear is connected to the first output member so as to rotate integrally with it. The first carrier is connected to the second output member so as to rotate integrally with it. The second planetary gear mechanism is a single-pinion type planetary gear mechanism comprising a second sun gear, a second carrier, and a second ring gear, and is arranged adjacent to the first planetary gear mechanism on the axial side. The third planetary gear mechanism is a single-pinion type planetary gear mechanism comprising a third sun gear, a third carrier, and a third ring gear, and is arranged adjacent to the second planetary gear mechanism on the first axial side. The number of teeth of the second sun gear and the number of teeth of the third sun gear are the same. The number of teeth of the second ring gear and the number of teeth of the third ring gear are the same. The second ring gear and the third ring gear are connected so as to rotate integrally with each other. The driven sun gear, which is either the second sun gear or the third sun gear, is driven and connected to a torque control device that controls the torque transmitted to the driven sun gear. The fixed sun gear, which is either the second sun gear or the third sun gear, is fixed to the non-rotating member. The first carrier and the second carrier are connected so as to rotate integrally with each other. A vehicle drive system in which the first ring gear and the third carrier are connected by a member that passes radially outward from the second ring gear and the third ring gear so as to rotate integrally with each other.

2. An input member connected to the first drive source, A first output member is driven and connected to the first wheel, A second output member is arranged coaxially with the first output member and is driven and connected to the second wheel, A first planetary gear mechanism distributes the torque transmitted from the first drive source to the input member to the first output member and the second output member, The second planetary gear mechanism, A vehicle drive system comprising a third planetary gear mechanism, The direction along the rotation axis of the first output member and the second output member is defined as the axial direction, one side in the axial direction is defined as the first axial side, and the other side in the axial direction is defined as the second axial side. The first planetary gear mechanism is a double pinion type planetary gear mechanism comprising a first sun gear, a first carrier, and a first ring gear. The first ring gear is connected to the input member so as to rotate integrally with it. The first sun gear is connected to the first output member so as to rotate integrally with it. The first carrier is connected to the second output member so as to rotate integrally with it. The second planetary gear mechanism is a single-pinion type planetary gear mechanism comprising a second sun gear, a second carrier, and a second ring gear, and is arranged adjacent to the first planetary gear mechanism on the axial side. The third planetary gear mechanism is a single-pinion type planetary gear mechanism comprising a third sun gear, a third carrier, and a third ring gear, and is arranged adjacent to the second planetary gear mechanism on the first axial side. The number of teeth of the second sun gear and the number of teeth of the third sun gear are the same. The number of teeth of the second ring gear and the number of teeth of the third ring gear are the same. The second ring gear and the third ring gear are connected so as to rotate integrally with each other. The driven sun gear, which is either the second sun gear or the third sun gear, is driven and connected to a torque control device that controls the torque transmitted to the driven sun gear. The fixed sun gear, which is either the second sun gear or the third sun gear, is fixed to the non-rotating member. The first carrier and the second carrier are connected so as to rotate integrally with each other. The first ring gear and the third carrier are connected so as to rotate integrally with each other. The first carrier supports the first pinion gear pair, and the second carrier supports the second pinion gear. A vehicle drive device wherein a member disposed between the first pinion gear pair and the second pinion gear in the axial direction is a member shared by the first carrier and the second carrier, and provides support for the first pinion gear pair and the second pinion gear.

3. An input member connected to the first drive source, A first output member is driven and connected to the first wheel, A second output member is arranged coaxially with the first output member and is driven and connected to the second wheel, A first planetary gear mechanism distributes the torque transmitted from the first drive source to the input member to the first output member and the second output member, The second planetary gear mechanism, A vehicle drive system comprising a third planetary gear mechanism, The direction along the rotation axis of the first output member and the second output member is defined as the axial direction, one side in the axial direction is defined as the first axial side, and the other side in the axial direction is defined as the second axial side. The first planetary gear mechanism is a double pinion type planetary gear mechanism comprising a first sun gear, a first carrier, and a first ring gear. The first ring gear is connected to the input member so as to rotate integrally with it. The first sun gear is connected to the first output member so as to rotate integrally with it. The first carrier is connected to the second output member so as to rotate integrally with it. The second planetary gear mechanism is a single-pinion type planetary gear mechanism comprising a second sun gear, a second carrier, and a second ring gear, and is arranged adjacent to the first planetary gear mechanism on the axial side. The third planetary gear mechanism is a single-pinion type planetary gear mechanism comprising a third sun gear, a third carrier, and a third ring gear, and is arranged adjacent to the second planetary gear mechanism on the first axial side. The number of teeth of the second sun gear and the number of teeth of the third sun gear are the same. The number of teeth of the second ring gear and the number of teeth of the third ring gear are the same. The second ring gear and the third ring gear are connected so as to rotate integrally with each other. The driven sun gear, which is either the second sun gear or the third sun gear, is driven and connected to a torque control device that controls the torque transmitted to the driven sun gear. The fixed sun gear, which is either the second sun gear or the third sun gear, is fixed to the non-rotating member. The first carrier and the second carrier are connected so as to rotate integrally with each other. The first ring gear and the third carrier are connected so as to rotate integrally with each other. The system further comprises a case member configured to rotate integrally with the input member, the first ring gear, and the third carrier, The direction perpendicular to the rotation axis of the first output member and the second output member is defined as the radial direction. The case member is formed to cover the radially outer surfaces of the first planetary gear mechanism, the second planetary gear mechanism, and the third planetary gear mechanism, in a vehicle drive device.

4. An input member connected to the first drive source, A first output member is driven and connected to the first wheel, A second output member is arranged coaxially with the first output member and is driven and connected to the second wheel, A first planetary gear mechanism distributes the torque transmitted from the first drive source to the input member to the first output member and the second output member, The second planetary gear mechanism, A vehicle drive system comprising a third planetary gear mechanism, The direction along the rotation axis of the first output member and the second output member is defined as the axial direction, one side in the axial direction is defined as the first axial side, and the other side in the axial direction is defined as the second axial side. The first planetary gear mechanism is a double pinion type planetary gear mechanism comprising a first sun gear, a first carrier, and a first ring gear. The first ring gear is connected to the input member so as to rotate integrally with it. The first sun gear is connected to the first output member so as to rotate integrally with it. The first carrier is connected to the second output member so as to rotate integrally with it. The second planetary gear mechanism is a single-pinion type planetary gear mechanism comprising a second sun gear, a second carrier, and a second ring gear, and is arranged adjacent to the first planetary gear mechanism on the axial side. The third planetary gear mechanism is a single-pinion type planetary gear mechanism comprising a third sun gear, a third carrier, and a third ring gear, and is arranged adjacent to the second planetary gear mechanism on the first axial side. The number of teeth of the second sun gear and the number of teeth of the third sun gear are the same. The number of teeth of the second ring gear and the number of teeth of the third ring gear are the same. The second ring gear and the third ring gear are connected so as to rotate integrally with each other. The driven sun gear, which is either the second sun gear or the third sun gear, is driven and connected to a torque control device that controls the torque transmitted to the driven sun gear. The fixed sun gear, which is either the second sun gear or the third sun gear, is fixed to the non-rotating member. The first carrier and the second carrier are connected so as to rotate integrally with each other. The first ring gear and the third carrier are connected so as to rotate integrally with each other. The torque control device is a vehicle drive system comprising a first friction engagement device that selectively engages a first interlocking member, which rotates in conjunction with the driven sun gear, with the non-rotating member.

5. A vehicle drive system according to any one of claims 1, 3, or 4, wherein a part of the first carrier and a part of the second carrier are shared.

6. The first output member and the second output member are arranged to extend in opposite directions in the axial direction. A first connecting shaft for connecting the second sun gear to either the torque control device or the non-rotating member is arranged to extend from the second sun gear toward the first axial direction. A second connecting shaft for connecting the third sun gear to either the torque control device or the non-rotating member is arranged to extend from the third sun gear toward the first axial direction. The direction perpendicular to the rotation axis of the first output member and the second output member is defined as the radial direction. The first connecting shaft is positioned radially outward from the first output member or the second output member. The vehicle drive device according to any one of claims 1 to 4, wherein the second connecting shaft is positioned radially outward from the first connecting shaft.

7. The vehicle drive device according to any one of claims 1 to 4, wherein the torque control device comprises a second drive source for applying both the torque on one side of the rotational direction of the driven sun gear and the torque on the other side of the rotational direction to the driven sun gear.

8. The torque control device further comprises a power transmission mechanism that transmits the driving force of the second drive source to the driven sun gear, The power transmission mechanism comprises a driven gear connected to the driven sun gear so as to rotate integrally with it, and a drive gear that meshes with the driven gear and is driven by the second drive source. The driven gear has a larger diameter than the second ring gear and the third ring gear. The vehicle drive device according to claim 7, wherein the drive gear has a smaller diameter than the driven gear.

9. The vehicle drive device according to claim 4, further comprising a second friction engagement device for selectively engaging a second interlocking member, which rotates in conjunction with any of the first sun gear, the first carrier, the first ring gear, and the second ring gear, with the non-rotating member, without going through the first planetary gear mechanism, the second planetary gear mechanism, and the third planetary gear mechanism.

10. The first interlocking member and the second interlocking member are arranged coaxially. The first friction engagement device is positioned on the first axial side with respect to the third planetary gear mechanism. The second friction engagement device is positioned on the second axial side with respect to the first planetary gear mechanism. The vehicle drive device according to claim 9, wherein, in an axial view along the axial direction, both the first friction engagement device and the second friction engagement device are arranged to overlap with at least one of the first planetary gear mechanism, the second planetary gear mechanism, and the third planetary gear mechanism.

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