Vehicle drive device

Abstract

A second gear (33) meshes with a first gear (32) and is coupled to an output member (2) so as to rotate together therewith. A rotor (12), a planetary gear mechanism (31), and the first gear (32) are disposed on a first axis (X1) in the stated order from a first axial-direction side (L1) toward a second axial-direction side (L2). A coupling member (6), a differential gear mechanism (4), and the second gear (33) are disposed on a second axis (X2) parallel to the first axis (X1) in the stated order from the first axial-direction side (L1) toward the second axial-direction side (L2). The planetary gear mechanism (31) has a diameter smaller than that of a rotating electric machine (1) and larger than that of the first gear (32). The differential gear mechanism (4) has a diameter smaller than that of the second gear (33) and larger than that of the coupling member (6).

Description

[Technical field]

[0001] The present invention relates to a vehicle drive device including a rotating electric machine with a rotor, an output member drivingly connected to wheels, a power transmission mechanism that transmits the rotation of the rotor to the output member, and a differential gear mechanism that distributes the torque transmitted to the output member to a pair of wheels. [Background technology]

[0002] An example of such a vehicle drive device is disclosed in the following Patent Document 1. In the following explanations of the "Background Art" and "Problems to be Solved by the Invention", reference symbols in Patent Document 1 will be cited in parentheses.

[0003] In the vehicle drive device (100) of Patent Document 1, a power transmission mechanism that transmits rotation of a rotor (12) of a rotating electric machine (1) to a differential case (33) serving as an output member includes a speed change gear mechanism (21), a speed change output gear (22) to which the rotation after speed change by the speed change gear mechanism (21) is transmitted, and a differential input gear (31) that meshes with the speed change output gear (22). A differential gear mechanism (3) distributes the rotation transmitted to the differential input gear (31) to a pair of wheels (W). In this vehicle drive device (100), the differential input gear (31) is disposed so as to overlap both the rotating electric machine (1) and the speed change gear mechanism (21) when viewed in the axial direction, thereby preventing the radial dimension (R) of the vehicle drive device (100) from becoming large. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-175707 A Summary of the Invention [Problem to be solved by the invention]

[0005] 1 of Patent Document 1, in this vehicle drive device (100), a rotating electric machine (1) having a larger diameter than the transmission output gear (22) and a transmission gear mechanism (21) having a larger diameter than the transmission output gear (22) are arranged on a first shaft (A1) on which a transmission output gear (22) meshing with a differential input gear (31) is arranged, on both sides of the transmission output gear (22) in the axial direction (L). Therefore, even if the second shaft (A2) on which the differential input gear (31) is arranged is arranged close to the first shaft (A1), it is necessary to avoid interference between the members arranged on the second shaft (A2) and the relatively large-diameter members arranged on the first shaft (A1) on both sides of the transmission output gear (22) in the axial direction (L), which may hinder the reduction in the radial dimension (R) of the vehicle drive device (100).

[0006] Therefore, it is desirable to realize a technique that can easily reduce the radial dimensions of a vehicle drive device. [Means for solving the problem]

[0007] In view of the above, the characteristic configuration of the vehicle drive device is as follows: A rotating electric machine having a rotor; An output member that is drivingly connected to a wheel of the vehicle; a power transmission mechanism that transmits the rotation of the rotor to the output member; a differential gear mechanism that distributes the torque transmitted to the output member to the pair of wheels, The power transmission mechanism includes a planetary gear mechanism, a first gear, and a second gear. the second gear is in mesh with the first gear and is connected to the output member so as to rotate integrally therewith; A direction along the rotation axis of the rotor is defined as an axial direction, one side in the axial direction is defined as an axial first side, the other side in the axial direction is defined as an axial second side, and one of the pair of wheels that is disposed on the axial first side is defined as a target wheel, The differential gear mechanism is connected to the target wheel via a connecting member, the rotor, the planetary gear mechanism, and the first gear are arranged on a first shaft in the order described above from the first axial direction side to the second axial direction side, the connecting member, the differential gear mechanism, and the second gear are arranged on a second shaft parallel to the first shaft in the order described from the first axial side toward the second axial side, the planetary gear mechanism has a smaller diameter than the rotating electric machine and a larger diameter than the first gear, The differential gear mechanism has a smaller diameter than the second gear and a larger diameter than the connecting member.

[0008] According to this characteristic configuration, the rotating electric machine, the planetary gear mechanism, and the first gear arranged on the first shaft are arranged in an order in which the radial dimensions gradually decrease from the first axial side to the second axial side, and the connecting member, the differential gear mechanism, and the second gear arranged on the second shaft are arranged in an order in which the radial dimensions gradually increase from the first axial side to the second axial side. This makes it easy to keep the axial distance between the first and second shafts short while avoiding interference between the elements on the first shaft and the elements on the second shaft, and makes it easy to keep the radial dimensions of the vehicle drive device small. [Brief description of the drawings]

[0009] [Figure 1] 1 is a cross-sectional view taken along an axial direction of a vehicle drive device according to a first embodiment; [Diagram 2] FIG. 1 is a skeleton diagram of a vehicle drive device according to a first embodiment; [Diagram 3] FIG. 2 is a diagram showing the positional relationship of each element in the vehicle drive device according to the first embodiment as viewed in the axial direction; [Figure 4] FIG. 11 is a cross-sectional view taken along an axial direction of a vehicle drive device according to a second embodiment; [Diagram 5] FIG. 11 is a cross-sectional view taken along an axial direction of a vehicle drive device according to a third embodiment; [Figure 6] FIG. 13 is a cross-sectional view taken along an axial direction of a vehicle drive device according to a fourth embodiment; [Figure 7] FIG. 13 is a view showing the inside of a case of a vehicle drive device according to a fourth embodiment, as viewed from a second axial side. [Figure 8] FIG. 13 is a diagram showing a vehicle drive device according to a fourth embodiment, as viewed in a horizontal direction perpendicular to the axial direction. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] 1. First embodiment A vehicle drive device 100 according to a first embodiment will be described below with reference to the drawings. As shown in Fig. 1 and Fig. 2, the vehicle drive device 100 includes a rotating electric machine 1, an output member 2, and a power transmission mechanism 3. In this embodiment, the vehicle drive device 100 further includes a differential gear mechanism 4 and a case 9.

[0011] The rotating electric machine 1 includes a stator 11 and a rotor 12. An axial direction L, which will be described later, is a direction along the rotation axis of the rotor 12. The rotating electric machine 1 functions as a driving force source for a wheel W (see FIG. 2). The rotating electric machine 1 has a function as a motor (electric motor) that receives a supply of electric power to generate power, and a function as a generator (electric power generator) that receives a supply of power to generate electric power. Specifically, the rotating electric machine 1 is electrically connected to an electric storage device (not shown) such as a battery or a capacitor. The rotating electric machine 1 generates driving force by running using electric power stored in the electric storage device. The rotating electric machine 1 also generates power using driving force transmitted from the wheel W side to charge the electric storage device.

[0012] The output member 2 is drivingly connected to wheels W of a vehicle (a vehicle on which the vehicle drive device 100 is mounted). The power transmission mechanism 3 is configured to transmit the rotation of the rotor 12 to the output member 2. The power transmission mechanism 3 includes a planetary gear mechanism 31, a first gear 32, and a second gear 33. The differential gear mechanism 4 is configured to distribute the torque transmitted to the output member 2 to a pair of wheels W.

[0013] Here, in the present application, the term "driving connection" refers to a state in which two rotating elements are connected so as to be able to transmit a driving force, and includes a state in which the two rotating elements are connected so as to rotate integrally, or a state in which the two rotating elements are connected so as to be able to transmit a driving force via one or more transmission members. Such transmission members include various members that transmit rotation at the same speed or at a variable speed, such as shafts, gear mechanisms, belts, chains, etc. Note that 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 the term "driving connection" is used 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 passing through other rotating elements.

[0014] The rotor 12, the planetary gear mechanism 31, and the first gear 32 are disposed on a first axis X1 which serves as their axial centers. The output member 2 and the second gear 33 are disposed on a second axis X2 which serves as their axial centers. In this embodiment, the differential gear mechanism 4 is also disposed on the second axis X2. The first axis X1 and the second axis X2 are disposed so as to be parallel to each other.

[0015] In the following description, a direction parallel to the first axis X1 and the second axis X2 is referred to as the "axial direction L" of the vehicle drive device 100. One side of the axial direction L is referred to as the "axial first side L1", and the other side of the axial direction L is referred to as the "axial second side L2". In this embodiment, in the axial direction L, the side where the rotor 12 is arranged with respect to the planetary gear mechanism 31 is referred to as the axial first side L1, and the opposite side is referred to as the axial second side L2. In addition, a direction perpendicular to each of the first axis X1 and the second axis X2 is referred to as the "radial direction R" based on each axis. Note that when it is not necessary to distinguish which axis is used as the reference or when it is clear which axis is used as the reference, it may be simply referred to as the "radial direction R".

[0016] 1, a case 9 accommodates a rotating electric machine 1 and a power transmission mechanism 3. In this embodiment, the case 9 also accommodates an output member 2 and a differential gear mechanism 4.

[0017] In this embodiment, the case 9 comprises a first case part 91, a second case part 92 joined to the first case part 91 from a first axial side L1, and a third case part 93 joined to the first case part 91 from a second axial side L2.

[0018] The first case portion 91 includes a first peripheral wall portion 91a, a second peripheral wall portion 91b, and a partition portion 91c.

[0019] The first peripheral wall portion 91a is formed so as to cover the outside of the rotating electric machine 1 in the radial direction R. The second peripheral wall portion 91b is formed so as to cover the outside of the planetary gear mechanism 31 and the differential gear mechanism 4 in the radial direction R. The partition wall portion 91c is formed so as to separate the internal space of the first peripheral wall portion 91a from the internal space of the second peripheral wall portion 91b in the axial direction L. In this embodiment, the first peripheral wall portion 91a is disposed on the first axial side L1 with respect to the partition wall portion 91c, and the second peripheral wall portion 91b is disposed on the second axial side L2 with respect to the partition wall portion 91c. The first peripheral wall portion 91a is formed in a cylindrical shape that opens to the first axial side L1, and the second peripheral wall portion 91b is formed in a cylindrical shape that opens to the second axial side L2.

[0020] The second case portion 92 includes a first side wall portion 92a. The first side wall portion 92a is formed so as to cover a first axial side L1 of the rotating electric machine 1. In this embodiment, the second case portion 92 is joined to the first case portion 91 from the first axial side L1 such that an opening of the first peripheral wall portion 91a on the first axial side L1 is closed by the first side wall portion 92a.

[0021] The third case portion 93 includes a second side wall portion 93a. The second side wall portion 93a is formed so as to cover the second axial side L2 of the power transmission mechanism 3 and the differential gear mechanism 4. In this embodiment, the third case portion 93 is joined to the first case portion 91 from the second axial side L2 so that the opening of the second peripheral wall portion 91b on the second axial side L2 is closed by the second side wall portion 93a.

[0022] As shown in FIG. 1, the stator 11 of the rotating electric machine 1 includes a cylindrical stator core 11a. The stator core 11a is fixed to a non-rotating member NR. In this embodiment, the stator core 11a is fixed to a first peripheral wall portion 91a of a case 9 serving as the non-rotating member NR. The rotor 12 of the rotating electric machine 1 includes a cylindrical rotor core 12a. The rotor core 12a is supported rotatably relative to the stator core 11a. In this embodiment, the rotor 12 further includes a rotor shaft 12b connected to rotate integrally with the rotor core 12a.

[0023] In this embodiment, the rotating electric machine 1 is an inner rotor type rotating electric machine. Therefore, the rotor core 12a is disposed on the inside in the radial direction R with respect to the stator core 11a. Also, the rotor shaft 12b is disposed on the inside in the radial direction R with respect to the rotor core 12a.

[0024] In this embodiment, the rotating electric machine 1 is a rotating field type rotating electric machine. Therefore, a stator coil is wound around the stator core 11a. In this embodiment, the stator coil is wound around the stator core 11a so that a pair of coil end portions 11b protruding on both sides in the axial direction L are formed with respect to the stator core 11a. Although not shown, a permanent magnet is provided in the rotor core 12a.

[0025] In this embodiment, rotor shaft 12b is formed in a cylindrical shape having an axis along the axial direction L. In this embodiment, rotor shaft 12b is disposed so as to protrude from rotor core 12a on both sides in the axial direction L. A portion of rotor shaft 12b protruding from rotor core 12a to a first axial side L1 is rotatably supported by a first side wall portion 92a of case 9 via a first rotor bearing B11. On the other hand, a portion of rotor shaft 12b protruding from rotor core 12a to a second axial side L2 is rotatably supported by a partition wall portion 91c of case 9 via a second rotor bearing B12.

[0026] The planetary gear mechanism 31 is configured to reduce the rotation speed of the rotor 12 and transmit the rotation to the first gear 32. The planetary gear mechanism 31 includes a sun gear SG, a carrier CR, and a ring gear RG.

[0027] The sun gear SG is connected to the rotor 12 so as to rotate integrally with the rotor 12. In this embodiment, the sun gear SG is connected to the rotor shaft 12b via the input shaft 5 so as to rotate integrally with the rotor shaft 12b.

[0028] The input shaft 5 is formed to extend along the axial direction L. In this embodiment, the input shaft 5 is formed to extend from the sun gear SG to a first axial side L1. In the example shown in Fig. 1, the input shaft 5 is formed integrally with the sun gear SG.

[0029] In this embodiment, the input shaft 5 includes a connecting portion 51 and an enlarged diameter portion 52. The connecting portion 51 is connected to the rotor shaft 12b so as to rotate integrally with the rotor shaft 12b. In this embodiment, the connecting portion 51 is disposed so as to penetrate the partition wall portion 91c of the case 9 in the axial direction L. The connecting portion 51 is disposed on the inside of the rotor shaft 12b in the radial direction R, and is connected to the rotor shaft 12b by spline engagement. The enlarged diameter portion 52 is formed to have a larger diameter than the connecting portion 51. In this embodiment, the enlarged diameter portion 52 is disposed on the second axial side L2 with respect to the partition wall portion 91c. A first thrust bearing B3 that supports the input shaft 5 in the axial direction L is disposed between the enlarged diameter portion 52 and the partition wall portion 91c in the axial direction L.

[0030] In this embodiment, the carrier CR rotatably supports a first pinion gear PG1 and a second pinion gear PG2 that rotate integrally with each other. The first pinion gear PG1 meshes with a sun gear SG. The second pinion gear PG2 meshes with a ring gear RG. In this embodiment, the second pinion gear PG2 is formed to have a smaller diameter than the first pinion gear PG1. In this embodiment, the second pinion gear PG2 is disposed on the axial first side L1 of the first pinion gear PG1. That is, in this embodiment, the second pinion gear PG2 is disposed on the side of the rotating electric machine 1 in the axial direction L of the first pinion gear PG1. Each of the first pinion gear PG1 and the second pinion gear PG2 rotates (spins) around its own axis and rotates (revolves) around the sun gear SG together with the carrier CR. Each of the first pinion gears PG1 and the second pinion gears PG2 is provided at intervals along its own revolution locus.

[0031] In the following description, one of the carrier CR and the ring gear RG will be referred to as a "first element E1," and the other will be referred to as a "second element E2."

[0032] The first element E1 is connected to rotate integrally with the first gear 32. In this embodiment, the carrier CR is connected to rotate integrally with the first gear 32. That is, in this embodiment, the carrier CR is the first element E1.

[0033] The second element E2 is fixed to the non-rotating member NR. In this embodiment, the ring gear RG is fixed to the second circumferential wall portion 91b of the case 9 serving as the non-rotating member NR. That is, in this embodiment, the ring gear RG is the second element E2.

[0034] In this manner, in this embodiment, the ring gear RG is fixed to the non-rotating member NR, The second pinion gears PG2 are arranged closer to the rotating electric machine 1 in the axial direction L than the first pinion gears PG1.

[0035] Generally, a support member serving as a non-rotating member NR is often provided between the rotating electric machine 1 and the planetary gear mechanism 31 in the axial direction L to rotatably support the rotor 12. According to this configuration, it becomes easy to fix the ring gear RG, which meshes with the second pinion gear PG2 arranged relatively close to the rotating electric machine 1, to the non-rotating member NR. This makes it easy to realize a configuration in which the ring gear RG is fixed to the non-rotating member NR while keeping the dimension of the vehicle drive device 100 in the axial direction L small.

[0036] In this embodiment, the first element E1 includes a first connecting portion 311. The first gear 32 includes a second connecting portion 321. The first connecting portion 311 and the second connecting portion 321 are configured to be connected to each other so as not to rotate relative to each other. In this embodiment, the first connecting portion 311 is formed in a cylindrical shape with the first axis X1 as its axis. The first connecting portion 311 includes a first engaging portion 311a and a first pressure contact portion 311b. In this embodiment, the second connecting portion 321 is disposed on the inside in the radial direction R with respect to the first connecting portion 311. The second connecting portion 321 includes a second engaging portion 321a and a second pressure contact portion 321b.

[0037] The first engagement portion 311a and the second engagement portion 321a are formed to engage with each other so as not to rotate relative to each other. In this embodiment, the first engagement portion 311a extends in the axial direction L and is configured with a plurality of internal teeth arranged in the circumferential direction centered on the first axis X1. The second engagement portion 321a extends in the axial direction L and is configured with a plurality of external teeth arranged in the circumferential direction centered on the first axis X1.

[0038] The first pressure contact portion 311b and the second pressure contact portion 321b are formed to be in pressure contact with each other so as to be immovable relative to each other in the radial direction R. In this embodiment, the inner peripheral surface of the first pressure contact portion 311b and the outer peripheral surface of the second pressure contact portion 321b are formed to be in pressure contact with each other (in other words, to be in contact with pressure). In this example, the second pressure contact portion 321b is press-fitted into the first pressure contact portion 311b or fitted without a gap. In this embodiment, the first pressure contact portion 311b is disposed on the second axial side L2 from the first engagement portion 311a. And the second pressure contact portion 321b is disposed on the second axial side L2 from the second engagement portion 321a.

[0039] In this embodiment, the planetary gear mechanism 31 is disposed on the second axial side L2 with respect to the rotating electric machine 1 and on the first axial side L1 with respect to the first gear 32. That is, in this embodiment, the rotor 12, the planetary gear mechanism 31, and the first gear 32 are disposed on the first axis X1 in the order described above from the first axial side L1 toward the second axial side L2.

[0040] In this embodiment, the rotating electric machine 1 has a larger diameter than the planetary gear mechanism 31. In the example shown in FIG. 1, the outer circumferential surface of the stator core 11a of the rotating electric machine 1 is located on the outer side in the radial direction R of the ring gear RG of the planetary gear mechanism 31. In addition, in this embodiment, the first gear 32 has a smaller diameter than the planetary gear mechanism 31. In the example shown in FIG. 1, the outermost part of the first gear 32 in the radial direction R is located on the inner side in the radial direction R of the ring gear RG of the planetary gear mechanism 31. In this way, the planetary gear mechanism 31 has a smaller diameter than the rotating electric machine 1 and a larger diameter than the first gear 32. Therefore, in this embodiment, the rotating electric machine 1, the planetary gear mechanism 31, and the first gear 32 are arranged on the first axis X1 so that the dimensions in the radial direction R gradually decrease from the axial first side L1 toward the axial second side L2.

[0041] In this embodiment, the first gear 32 is rotatably supported with respect to the case 9 via a first support bearing B2. The first support bearing B2 is disposed on the inside of the first gear 32 in the radial direction R at a position overlapping with the first gear 32 as viewed in the radial direction along the radial direction R. Here, with regard to the arrangement of two elements, "overlapping as viewed in a specific direction" refers to the existence of at least a portion of an area where a virtual line parallel to the line of sight intersects with both of the two elements when the virtual line is moved in each direction perpendicular to the virtual line.

[0042] In this embodiment, the second side wall portion 93a of the case 9 is disposed adjacent to the first gear 32 on the second axial side L2. In this embodiment, the second side wall portion 93a functions as a "support wall portion SW" disposed adjacent to the first gear 32 on the side opposite to the planetary gear mechanism 31 in the axial direction L.

[0043] In this embodiment, a first protrusion 93b that protrudes toward the first axial side L1 is formed on the second side wall portion 93a. In this embodiment, the first protrusion 93b is formed so as to support the first support bearing B2 from the inside in the radial direction R. In this manner, in this embodiment, the first protrusion 93b functions as a "bearing support portion SWa" that supports the first support bearing B2 from the inside in the radial direction R.

[0044] In this embodiment, the first gear 32 further includes a supported portion 322. The supported portion 322 is disposed between the input shaft 5 and the first protruding portion 93b of the case 9 in the axial direction L. In this embodiment, the supported portion 322 is formed so as to protrude inward in the radial direction R from the second connecting portion 321.

[0045] In this embodiment, the second thrust bearing B4 is disposed between the supported portion 322 and the input shaft 5 in the axial direction L. The third thrust bearing B5 is disposed between the supported portion 322 and the first protruding portion 93b in the axial direction L. Thus, in this embodiment, the first gear 32 is supported in the axial direction L relative to the case 9 by the second thrust bearing B4 and the third thrust bearing B5.

[0046] The second gear 33 meshes with the first gear 32. The second gear 33 is connected to the output member 2 so as to rotate integrally with the output member 2. In this embodiment, the second gear 33 is formed to have a larger diameter than the first gear 32. Therefore, in this embodiment, the rotation of the first element E1 (here, the carrier CR) is reduced in speed between the first gear 32 and the second gear 33 and is transmitted to the output member 2.

[0047] In this embodiment, the second gear 33 is rotatably supported with respect to the case 9 via a second support bearing B6. The second support bearing B6 is disposed on the inner side of the second gear 33 in the radial direction R and at a position overlapping with the second gear 33 as viewed in the radial direction along the radial direction R.

[0048] In this embodiment, a second protruding portion 93c that protrudes toward the first axial side L1 is formed on the second side wall portion 93a. In this embodiment, the second protruding portion 93c is formed so as to support the second support bearing B6 from the inside in the radial direction R.

[0049] In this embodiment, each of the first gear 32 and the second gear 33 is a double helical gear. To explain further, the first gear 32 has a first meshing portion 32a and a second meshing portion 32b whose teeth have different twist directions. The second gear 33 has a third meshing portion 33a and a fourth meshing portion 33b whose teeth have different twist directions. The first meshing portion 32a and the third meshing portion 33a mesh with each other, and the second meshing portion 32b and the fourth meshing portion 33b mesh with each other. Here, the "twist direction of the teeth" refers to the direction in which the teeth of the gear are inclined with respect to the axis of the target gear.

[0050] According to this configuration, compared to a configuration in which the first gear 32 and the second gear 33 are simple helical gears, it is possible to reduce the thrust force generated by the meshing of the first gear 32 and the second gear 33. This allows the support structure of the first gear 32 and the second gear 33 to be simplified. Therefore, it is easy to reduce the size of the vehicle drive device 100.

[0051] In this embodiment, the differential gear mechanism 4 includes a differential case 41, a pair of pinion gears 42, and a first side gear 43 and a second side gear 44. Here, the pair of pinion gears 42, and the first side gear 43 and the second side gear 44 are all bevel gears.

[0052] The differential case 41 is a hollow member that houses a pair of pinion gears 42, a first side gear 43, and a second side gear 44. The differential case 41 is connected to the second gear 33 so as to rotate integrally with the second gear 33. Therefore, in this embodiment, the differential case 41 corresponds to the output member 2.

[0053] In this embodiment, the differential case 41 is rotatably supported with respect to the case 9 via a differential bearing B7. In the example shown in Fig. 1, an end of the differential case 41 on the first axial side L1 is rotatably supported with respect to the second peripheral wall portion 91b of the case 9 via the differential bearing B7.

[0054] The pair of pinion gears 42 are disposed to face each other with a gap therebetween in the radial direction R based on the second axis X2. The pair of pinion gears 42 are attached to a pinion shaft 42a supported to rotate integrally with the differential case 41. Each of the pair of pinion gears 42 is configured to be rotatable (spin) about the pinion shaft 42a and rotatable (revolve) about the second axis X2.

[0055] The first side gear 43 and the second side gear 44 mesh with the pair of pinion gears 42. The first side gear 43 and the second side gear 44 are arranged to rotate about the second axis X2. The first side gear 43 is arranged on the first axial side L1 with respect to the pinion shaft 42a. The second side gear 44 is arranged on the second axial side L2 with respect to the pinion shaft 42a.

[0056] In this embodiment, the first side gear 43 is connected to a first drive shaft DS1 (see FIG. 2) drivingly connected to a wheel W on a first axial side L1 via a transmission shaft 6 extending along the axial direction L so as to rotate integrally with the first drive shaft DS1. In the example shown in FIG. 1, the transmission shaft 6 is inserted from the first axial side L1 on the inside in the radial direction R relative to the first side gear 43, and they are connected to each other by spline engagement. As shown in FIG. 2, if one of the pair of wheels W arranged on the first axial side L1 is a target wheel WT, the differential gear mechanism 4 is connected to the target wheel WT via the transmission shaft 6. In this embodiment, the transmission shaft 6 corresponds to the "connecting member."

[0057] The transmission shaft 6 is disposed on the second axis X2. In this embodiment, the transmission shaft 6 is disposed so as to pass outside the rotating electric machine 1 inside the case 9 in the radial direction R and penetrate the first side wall portion 92a in the axial direction L. The transmission shaft 6 is connected to the first drive shaft DS1 (see FIG. 2) so as to rotate integrally with the first drive shaft DS1. In the example shown in FIG. 1, a portion of the transmission shaft 6 on the first axial side L1 from the first case portion 91 is formed into a cylindrical shape that opens to the first axial side L1. The first drive shaft DS1 is inserted from the first axial side L1 into the cylindrical portion of the transmission shaft 6 on the inside in the radial direction R, and they are connected to each other by spline engagement.

[0058] In this embodiment, the second side gear 44 is connected to a second drive shaft DS2 (see FIG. 2) drivingly connected to a wheel W on the second axial side L2 so as to rotate integrally with the second side gear 44. In the example shown in FIG. 1, the second drive shaft DS2 is inserted from the second axial side L2 to the inside in the radial direction R of the second side gear 44, and they are connected to each other by spline engagement.

[0059] In this embodiment, the differential gear mechanism 4 is disposed on the first axial side L1 relative to the second gear 33 and on the second axial side L2 relative to the transmission shaft 6. That is, in this embodiment, the transmission shaft 6, the differential gear mechanism 4, and the second gear 33 are disposed on the second axis X2 parallel to the first axis X1 in the order described from the first axial side L1 toward the second axial side L2.

[0060] In this embodiment, the second gear 33 has a larger diameter than the differential gear mechanism 4. In the example shown in FIG. 1, the part of the second gear 33 located on the outermost side in the radial direction R is located on the outer side in the radial direction R of the part of the pinion gear 42 of the differential gear mechanism 4 located on the outermost side in the radial direction R. In addition, the transmission shaft 6 has a smaller diameter than the differential gear mechanism 4. In the example shown in FIG. 1, the part of the transmission shaft 6 located on the outermost side in the radial direction R is located on the inner side in the radial direction R of the part of the pinion gear 42 of the differential gear mechanism 4 located on the outermost side in the radial direction R. In this way, the differential gear mechanism 4 has a smaller diameter than the second gear 33 and a larger diameter than the transmission shaft 6. Therefore, in this embodiment, the transmission shaft 6, the differential gear mechanism 4, and the second gear 33 are arranged on the second axis X2 so that the dimension in the radial direction R gradually increases from the first axial side L1 toward the second axial side L2.

[0061] Fig. 3 shows the positional relationship of each element housed in the case 9 when viewed in the axial direction along the axial direction L. Note that the symbol "V" in Fig. 3 indicates the vertical direction of the vehicle drive device 100 in a vehicle-mounted posture. Here, the "vehicle-mounted posture" refers to the posture of the vehicle drive device 100 when mounted on the vehicle.

[0062] As shown in Fig. 3, in this embodiment, the first axis X1 is disposed above the second axis X2 in the vehicle mounting position. The symbol "H1" in Fig. 3 indicates an imaginary plane passing through the first axis X1 along the horizontal direction (direction perpendicular to the vertical direction V). The symbol "H2" in Fig. 3 indicates an imaginary plane passing through the second axis X2 along the horizontal direction (direction perpendicular to the vertical direction V).

[0063] As described above, the vehicle drive device 100 of this embodiment has the following features: A rotating electric machine 1 having a rotor 12; An output member 2 that is drivingly connected to wheels W of a vehicle; A vehicle drive device 100 including a power transmission mechanism 3 that transmits rotation of a rotor 12 to an output member 2, The power transmission mechanism 3 includes a planetary gear mechanism 31, a first gear 32, and a second gear 33. The planetary gear mechanism 31 includes a sun gear SG, a carrier CR, and a ring gear RG. The sun gear SG is connected to the rotor 12 so as to rotate integrally with the rotor 12. The carrier CR rotatably supports the first pinion gear PG1 and the second pinion gear PG2 which rotate integrally with each other, One of the carrier CR and the ring gear RG is connected to the first gear 32 so as to rotate integrally with the first gear 32, The other of the carrier CR and the ring gear RG is fixed to a non-rotating member NR, The second gear 33 is engaged with the first gear 32 and is connected to the output member 2 so as to rotate integrally therewith. The first pinion gear PG1 meshes with the sun gear SG, The second pinion gear PG2 has a smaller diameter than the first pinion gear PG1 and meshes with the ring gear RG. The rotor 12, the planetary gear mechanism 31, and the first gear 32 are disposed on a first axis X1, The output member 2 and the second gear 33 are disposed on a second axis X2 parallel to the first axis X1, In a vehicle mounted attitude, which is an attitude when the device is mounted on the vehicle, the first axis X1 is disposed above the second axis X2.

[0064] According to this configuration, a two-shaft configuration can be realized in which the rotating electric machine 1, the planetary gear mechanism 31, and the first gear 32, and the output member 2 and the second gear 33 are arranged on different axes. This makes it possible to keep the radial dimension R of the vehicle drive device 100 small, compared to a multi-shaft configuration with three or more shafts including a counter gear mechanism or the like. According to this configuration, the carrier CR of the planetary gear mechanism 31 supports the first pinion gear PG1 and the second pinion gear PG2, which have different outer diameters. The sun gear SG, which rotates integrally with the rotor 12, meshes with the large-diameter first pinion gear PG1. One of the carrier CR and the ring gear RG is connected to rotate integrally with the first gear 32, and the other of the carrier CR and the ring gear RG is fixed to the non-rotating member NR. The ring gear RG meshes with the small-diameter second pinion gear PG2. Therefore, compared to a configuration including a counter gear mechanism, for example, it is easy to ensure a large reduction ratio while keeping the radial dimension R of the vehicle drive device 100 small. As a result, even a small rotating electric machine 1 can transmit a high torque to the output member 2. Moreover, according to this configuration, the first axis X1 as the axis of the rotating electric machine 1 is disposed above the second axis X2 as the axis of the output member 2. This makes it easy to ensure the minimum ground clearance when the vehicle drive device 100 is mounted on a vehicle, even if the outer diameter of the rotating electric machine 1 is relatively large. As described above, according to this configuration, it is possible to realize a vehicle drive device 100 that can easily ensure a minimum ground clearance when mounted on a vehicle while ensuring a large reduction ratio.

[0065] 1 and 3, in this embodiment, the second gear 33 has a smaller diameter than the rotating electric machine 1. In addition, the second gear 33 and the planetary gear mechanism 31 overlap when viewed in the axial direction L. In the illustrated example, when viewed in the axial direction L, the second gear 33 overlaps with both the carrier CR and the ring gear RG of the planetary gear mechanism 31, but does not overlap with the sun gear SG.

[0066] According to this configuration, it is possible to reduce the dimension of the second gear 33 in the radial direction R. Also, compared to a configuration in which the second gear 33 and the planetary gear mechanism 31 are disposed spaced apart in the radial direction R, it is possible to reduce the dimension of the vehicle drive device 100 in the radial direction R.

[0067] As shown in FIG. 1, in this embodiment, the arrangement area of ​​the planetary gear mechanism 31 in the axial direction L and the arrangement area of ​​the differential gear mechanism 4 in the axial direction L overlap. Also, in this embodiment, the arrangement area of ​​the rotating electric machine 1 in the axial direction L and the arrangement area of ​​the transmission shaft 6 in the axial direction L overlap. Here, with regard to the arrangement of two members, "the arrangement areas in a specific direction overlap" means that at least a part of the arrangement area of ​​the other member in the specific direction is included in the arrangement area of ​​one member in the specific direction. Also, as shown in FIG. 1 and FIG. 3, in this embodiment, the rotating electric machine 1 and the differential gear mechanism 4 overlap in the axial direction L. In the example shown in FIG. 1, the differential gear mechanism 4 overlaps with the stator 11 of the rotating electric machine 1 in the axial direction L, but does not overlap with the rotor 12.

[0068] Thus, in this embodiment, the vehicle drive device 100 further includes a differential gear mechanism 4 that distributes the torque transmitted to the output member 2 to a pair of wheels W. The differential gear mechanism 4 is disposed on the second axis X2. The rotating electric machine 1 has a larger diameter than the planetary gear mechanism 31, The first gear 32 has a smaller diameter than the planetary gear mechanism 31. The second gear 33 has a larger diameter than the differential gear mechanism 4, The arrangement area of ​​the planetary gear mechanism 31 in the axial direction L overlaps with the arrangement area of ​​the differential gear mechanism 4 in the axial direction L, When viewed in the axial direction along the axial direction L, the rotating electric machine 1 and the differential gear mechanism 4 overlap each other.

[0069] According to this configuration, an arrangement region in the axial direction L of the planetary gear mechanism 31, which is formed with a smaller diameter than the rotating electric machine 1, overlaps with an arrangement region in the axial direction L of the differential gear mechanism 4, which is formed with a smaller diameter than the second gear 33. This makes it possible to shorten the axial distance between the first axis X1 as the axis of the planetary gear mechanism 31 and the second axis X2 as the axis of the differential gear mechanism 4. Therefore, it is possible to keep the dimension in the radial direction R of the vehicle drive device 100 small. Moreover, according to this configuration, the rotating electric machine 1 and the differential gear mechanism 4 overlap when viewed in the axial direction along the axial direction L. This makes it possible to keep the dimension of the vehicle drive device 100 in the radial direction R small, compared to a configuration in which the rotating electric machine 1 and the differential gear mechanism 4 are disposed spaced apart in the radial direction R.

[0070] As described above, in this embodiment, in the configuration further including the differential gear mechanism 4, The rotor 12, the planetary gear mechanism 31, and the first gear 32 are arranged on the first axis X1 in the order described above from the first axial side L1 to the second axial side L2, The differential gear mechanism 4 and the second gear 33 are disposed on the second shaft X2 in the order described from the first axial side L1 to the second axial side L2.

[0071] According to this configuration, on the first axis, the rotating electric machine 1, the planetary gear mechanism 31, and the first gear 32 are arranged so that the dimension in the radial direction R gradually decreases from the first axial side L1 toward the second axial side L2. On the other hand, on the second axis X2, the differential gear mechanism 4 and the second gear 33 are arranged so that the dimension in the radial direction R gradually increases from the first axial side L1 toward the second axial side L2. This makes it possible to keep the axial distance between the first axis X1 and the second axis X2 short while ensuring the dimension in the radial direction R required for each element on the first axis X1 and each element on the second axis X2. Therefore, the entire vehicle drive device 100 can be made compact in the radial direction R.

[0072] 2. Second embodiment A vehicle drive device 100 according to a second embodiment will be described below with reference to Fig. 4. In this embodiment, the positional relationship in the axial direction L between the planetary gear mechanism 31 and the first gear 32, and the positional relationship in the axial direction L between the second gear 33 and the differential gear mechanism 4 are different from those in the first embodiment. The following description will focus on the differences from the first embodiment. Note that points that are not particularly described are the same as those in the first embodiment.

[0073] As shown in Fig. 4, in this embodiment, the first gear 32 is disposed on the second axial side L2 with respect to the rotating electric machine 1 and on the first axial side L1 with respect to the planetary gear mechanism 31. That is, in this embodiment, the rotor 12, the first gear 32, and the planetary gear mechanism 31 are disposed on the first axis X1 in the order described from the first axial side L1 toward the second axial side L2. Also, in this embodiment, the second pinion gear PG2 is disposed on the second axial side L2 with respect to the first pinion gear PG1. That is, in this embodiment, the second pinion gear PG2 is disposed on the opposite side to the rotating electric machine 1 in the axial direction L with respect to the first pinion gear PG1.

[0074] In this embodiment, the partition wall portion 91c of the case 9 is disposed adjacent to the first axial side L1 of the first gear 32. In this manner, in this embodiment, the partition wall portion 91c corresponds to the "support wall portion SW" disposed adjacent to the first gear 32 on the side opposite to the planetary gear mechanism 31 in the axial direction L.

[0075] In this embodiment, the partition wall portion 91c is formed with a third protruding portion 91e that protrudes toward the second axial side L2. In this embodiment, the third protruding portion 91e is formed in a cylindrical shape that covers the outside of the input shaft 5 in the radial direction R. The third protruding portion 91e is formed so as to support the first support bearing B2 from the inside in the radial direction R. Thus, in this embodiment, the third protruding portion 91e corresponds to a "bearing support portion SWa" that supports the first support bearing B2 from the inside in the radial direction R. In this embodiment, the first protruding portion 93b is formed on the second side wall portion 93a, but does not function as the bearing support portion SWa.

[0076] In this embodiment, the carrier CR of the planetary gear mechanism 31 has a supported portion 322. In the example shown in Fig. 4, the supported portion 322 is formed so as to protrude inward in the radial direction R from a portion of the carrier CR on the second axial side L2 beyond the second pinion gear PG2. Note that in this embodiment, the first gear 32 does not have the supported portion 322.

[0077] In this embodiment, a second protrusion 93c is formed in the partition wall portion 91c to support the second support bearing B6 from the inside in the radial direction R. Also, in this embodiment, a differential bearing B7 supporting the differential case 41 is attached to the second side wall portion 93a.

[0078] 3. Third embodiment A vehicle drive device 100 according to the third embodiment will be described below with reference to FIG. 5. This embodiment differs from the first embodiment in that the ring gear RG is the first element E1 and the carrier CR is the second element E2. The following description will focus on the differences from the first embodiment. Note that the points not specifically described are the same as those in the first embodiment.

[0079] 5, in this embodiment, the ring gear RG is connected to the first gear 32 so as to rotate integrally with the first gear 32. That is, in this embodiment, the ring gear RG is the first element E1. In this example, the ring gear RG is connected to the first gear 32 via a connecting member 7 so as to rotate integrally with the first gear 32.

[0080] The connecting member 7 includes a radial extending portion 71 formed to extend along a radial direction R based on the first axis X1, and an axial extending portion 72 formed to extend along an axial direction L. In this example, an inner end portion of the radial extending portion 71 in the radial direction R is connected to the second connecting portion 321 of the first gear 32 by welding. The radial extending portion 71 and the axial extending portion 72 are integrally formed to connect an outer end portion of the radial extending portion 71 in the radial direction R to an end portion of the axial extending portion 72 on a second axial side L2.

[0081] In this example, at the end of the first axial side L1 of the axial extension portion 72, a plurality of claw portions protruding toward the first axial side L1 are arranged in the circumferential direction centered on the first axis X1. At the first connecting portion 311 of the ring gear RG as the first element E1, a plurality of claw portions protruding toward the outside in the radial direction R are arranged in the circumferential direction centered on the first axis X1. The plurality of claw portions of the axial extension portion 72 are engaged with the plurality of claw portions of the first connecting portion 311 of the ring gear RG from the second axial side L2. The plurality of claw portions of the axial extension portion 72 and the plurality of claw portions of the first connecting portion 311 of the ring gear RG are fixed by, for example, an annular fixing member so as not to move relative to each other in the axial direction L. Note that these claw portions may be formed so that the axial extension portion 72 moves relative to the first connecting portion 311 of the ring gear RG in the radial direction R, or may be formed so as not to move relative to each other.

[0082] In the present embodiment, the second pinion gear PG2 is disposed on the second axial side L2 of the first pinion gear PG1. That is, in the present embodiment, the second pinion gear PG2 is disposed on the opposite side of the rotating electric machine 1 in the axial direction L of the first pinion gear PG1.

[0083] In this embodiment, a fourth thrust bearing B8 is disposed between a portion of the carrier CR on the second axial side L2 of the second pinion gear PG2 and the axial direction L between the second connecting portion 321 of the first gear 32. The fourth thrust bearing B8 supports the carrier CR and the first gear 32 in the axial direction L so that they rotate relatively to each other.

[0084] In the present embodiment, each of the first gear 32 and the second gear 33 is a helical gear, not a double helical gear. Each of the first gear 32 and the second gear 33 may be a spur gear.

[0085] 4. Fourth embodiment A vehicle drive device 100 according to the fourth embodiment will be described below with reference to Fig. 6 to Fig. 8. The following description will focus on differences from the first embodiment. Points that are not particularly described are the same as those in the first embodiment.

[0086] As shown in FIG. 6, in this embodiment, at a connection portion between the input shaft 5 (specifically, the end 50 on the axial first side L1 of the input shaft 5) and the rotor shaft 12b (specifically, the end 12c on the axial second side L2 of the rotor shaft 12b), the expanded diameter portion 52 is disposed so as to abut against the rotor shaft 12b (specifically, the end face of the axial second side L2 of the rotor shaft 12b) from the axial second side L2, and a load generated on the sun gear SG toward the axial first side L1 is transmitted to the rotor shaft 12b and supported by the first rotor bearing B11. In addition, in this embodiment, a fifth thrust bearing BR that supports the input shaft 5 in the axial direction L is disposed between the input shaft 5 and the first protruding portion 93b in the axial direction L, and a load generated on the sun gear SG toward the axial second side L2 is supported by the fifth thrust bearing BR.

[0087] The vehicle drive device 100 includes an inverter device 20 that drives and controls a rotating electric machine 1. In this embodiment, as shown in FIG. 6, a case 9 accommodates the inverter device 20. Specifically, the case 9 includes an accommodation chamber forming portion 91f that forms an accommodation chamber for the inverter device 20, and a fourth case portion 94 that is joined to the accommodation chamber forming portion 91f so as to close an opening of the accommodation chamber. That is, the inverter device 20 is accommodated in a space surrounded by the accommodation chamber forming portion 91f and the fourth case portion 94. In this embodiment, the first case portion 91 includes the accommodation chamber forming portion 91f.

[0088] As shown in Fig. 6 and Fig. 8, the inverter device 20 includes a power module 21 in which a plurality of elements (switching elements, etc.) constituting an inverter circuit are modularized, an output bus bar 22 for outputting AC power from the power module 21, a capacitor 23 for smoothing the voltage between the positive and negative poles of the DC side of the inverter circuit, and a control board 24 on which a control device for controlling the inverter circuit is mounted. As shown in Fig. 6, the output bus bar 22 is electrically connected to the power line 13 drawn from the coil end portion 11b via a terminal block T. Note that Fig. 8 shows different parts offset in the horizontal direction (horizontal direction perpendicular to the axial direction L) between the upper side and the lower side. Also, one direction of the radial direction R coincides with the vertical direction V, and Fig. 8 shows the radial direction R that coincides with the vertical direction V.

[0089] As shown in Fig. 8, in this embodiment, at least a part of the inverter device 20 (here, at least the power module 21) is disposed radially outside the differential gear mechanism 4. Specifically, the power module 21 is disposed outside the differential gear mechanism 4 in the radial direction R, at a position overlapping with the differential gear mechanism 4 as viewed in the radial direction along the radial direction R. Also, in this embodiment, the power module 21 is disposed above the differential gear mechanism 4 (above the vertical direction V in the vehicle mounting position, the same applies below). Specifically, the power module 21 is disposed above the differential gear mechanism 4, at a position overlapping with the differential gear mechanism 4 as viewed in the vertical direction along the vertical direction V.

[0090] 8, in this embodiment, at least a part of the inverter device 20 (here, at least the capacitor 23) is disposed radially outward of the transmission shaft 6. Specifically, the capacitor 23 is disposed radially outward of the transmission shaft 6 in the radial direction R, at a position overlapping with the transmission shaft 6 when viewed in the radial direction along the radial direction R. Also, in this embodiment, the capacitor 23 is disposed above the transmission shaft 6. Specifically, the capacitor 23 is disposed above the transmission shaft 6, at a position overlapping with the transmission shaft 6 when viewed in the vertical direction along the vertical direction V.

[0091] 6 shows only a portion of the output bus bar 22, but in this embodiment, at least a portion of the inverter device 20 (here, at least the output bus bar 22) is disposed radially outside the planetary gear mechanism 31. Specifically, the output bus bar 22 is disposed outside the planetary gear mechanism 31 in the radial direction R, and at a position overlapping with the planetary gear mechanism 31 when viewed in the radial direction along the radial direction R. Also, in this embodiment, the output bus bar 22 is disposed above the planetary gear mechanism 31. Specifically, the output bus bar 22 is disposed above the planetary gear mechanism 31, and at a position overlapping with the planetary gear mechanism 31 when viewed in the vertical direction along the vertical direction V.

[0092] As shown in Figs. 6 and 7, the vehicle drive device 100 includes a catch tank 80 that stores oil scooped up by the planetary gear mechanism 31 or the second gear 33. In this embodiment, the catch tank 80 stores oil scooped up by the planetary gear mechanism 31 (here, the protrusion 34 provided on the carrier CR, see Fig. 7) and also stores oil scooped up by the second gear 33. The inside of the case 9 contains oil for lubricating (including cooling) the rotating electric machine 1 and the power transmission mechanism 3, and the catch tank 80 temporarily stores the oil in the case 9. The catch tank 80 is connected to an oil passage such as an oil passage 85 shown in Fig. 7 for supplying oil to parts to be lubricated, such as a bearing and a rotating shaft, and the oil in the catch tank 80 is supplied to the parts to be lubricated via the oil passage.

[0093] In this embodiment, the catch tank 80 is disposed radially outward of the first gear 32. Specifically, the catch tank 80 is disposed radially outward of the first gear 32 in the radial direction R and at a position overlapping with the first gear 32 as viewed in the radial direction along the radial direction R.

[0094] In the example shown in FIG. 7, the catch tank 80 is formed in an area surrounded by a partition wall 83 arranged along the outer periphery of the planetary gear mechanism 31 and the inner surface of the case 9. The catch tank 80 has a first inlet 81 that opens to the side of the second gear 33, and oil scooped up by the second gear 33 rotating in the direction indicated by the arrow in the figure is introduced into the catch tank 80 from the first inlet 81. In the example shown in the figure, a weir portion 84 for guiding the oil stored in the catch tank 80 to an oil passage 85 is provided so as to protrude outward in the radial direction R from the partition wall 83. Although not shown in the figure, in this example, the partition wall 83 (specifically, a portion of the partition wall 83 arranged along the outer periphery of the planetary gear mechanism 31) is arranged inside the radial direction R of the outer periphery of the stator core 11a of the rotating electric machine 1.

[0095] 7, the catch tank 80 has a second inlet 82 in addition to a first inlet 81. When the second gear 33 and the carrier CR are rotating in the direction opposite to the direction indicated by the arrow in the figure, the oil scooped up by the planetary gear mechanism 31 (here, the convex portion 34 provided on the carrier CR) is introduced into the catch tank 80 from the second inlet 82. In the example shown in the figure, the second inlet 82 is formed so as to penetrate the partition wall 83 in the radial direction R.

[0096] 5. Other embodiments (1) In the above embodiment, the planetary gear mechanism 31 is a planetary gear mechanism (double pinion type planetary gear mechanism) including a first pinion gear PG1 and a second pinion gear PG2 that rotate integrally with each other. However, the planetary gear mechanism 31 is not limited to such a configuration, and may be, for example, a single pinion type planetary gear mechanism.

[0097] (2) In the above embodiment, the vehicle drive device 100 is provided with the differential gear mechanism 4 that distributes torque to a pair of wheels W, and the differential case 41 functions as the output member 2. However, the present invention is not limited to such a configuration. For example, if the vehicle drive device 100 is configured not to include the differential gear mechanism 4, and the rotating electric machine 1 functions as a driving force source for one wheel W, an element that rotates integrally with a drive shaft drivingly connected to the wheel W may be used as the output member 2.

[0098] (3) The configurations disclosed in the above-described embodiments can be applied in combination with configurations disclosed in other embodiments, as long as no contradiction occurs. As for other configurations, the embodiments disclosed in this specification are merely examples in all respects. Therefore, various modifications can be made as appropriate within the scope of the present disclosure.

[0099] [Summary of the above embodiment] The vehicle drive device described above will now be outlined.

[0100] A rotating electric machine (1) having a rotor (12); An output member (2) that is drivingly connected to wheels (W) of a vehicle; a power transmission mechanism (3) that transmits rotation of the rotor (12) to the output member (2); a differential gear mechanism (4) that distributes torque transmitted to the output member (2) to a pair of the wheels (W), The power transmission mechanism (3) includes a planetary gear mechanism (31), a first gear (32), and a second gear (33), the second gear (33) is in mesh with the first gear (32) and is connected to the output member (2) so as to rotate integrally therewith; A direction along the rotation axis of the rotor (12) is defined as an axial direction (L), one side of the axial direction (L) is defined as an axial first side (L1), the other side of the axial direction (L) is defined as an axial second side (L2), and one of the pair of wheels (W) that is disposed on the axial first side (L1) is defined as a target wheel (WT), The differential gear mechanism (4) is connected to the target wheel (WT) via a connecting member (6), the rotor (12), the planetary gear mechanism (31), and the first gear (32) are arranged on a first shaft (X1) in the order described above from the first axial side (L1) to the second axial side (L2), the connecting member (6), the differential gear mechanism (4), and the second gear (33) are arranged on a second axis (X2) parallel to the first axis (X1) in the order described above from the first axial side (L1) to the second axial side (L2), the planetary gear mechanism (31) has a smaller diameter than the rotating electric machine (1) and a larger diameter than the first gear (32); The differential gear mechanism (4) has a smaller diameter than the second gear (33) and a larger diameter than the connecting member (6).

[0101] According to this configuration, the rotating electric machine (1), the planetary gear mechanism (31), and the first gear (32) arranged on the first shaft (X1) are arranged in an order in which the dimensions in the radial direction (R) become gradually smaller from the first axial side (L1) to the second axial side (L2), and the connecting member (6), the differential gear mechanism (4), and the second gear (33) arranged on the second shaft (X2) are arranged in an order in which the dimensions in the radial direction (R) become gradually larger from the first axial side (L1) to the second axial side (L2). This makes it easy to keep the inter-shaft distance between the first shaft (X1) and the second shaft (X2) short while avoiding interference between the elements on the first shaft (X1) and the elements on the second shaft (X2), and makes it easy to keep the radial direction (R) dimension of the vehicle drive device (100) small.

[0102] Here, it is preferable that, when viewed in the axial direction along the axial direction (L), the rotating electric machine (1) and the differential gear mechanism (4) overlap, and the second gear (33) and the planetary gear mechanism (31) overlap.

[0103] According to this configuration, the radial (R) dimension of the vehicle drive device (100) can be kept small compared to a configuration in which the rotating electric machine (1) and the differential gear mechanism (4) do not overlap when viewed in the axial direction, or a configuration in which the second gear (33) and the planetary gear mechanism (31) do not overlap when viewed in the axial direction.

[0104] In addition, an arrangement area of ​​the planetary gear mechanism (31) in the axial direction (L) overlaps with an arrangement area of ​​the differential gear mechanism (4) in the axial direction (L), It is preferable that an arrangement area of ​​the rotating electric machine (1) in the axial direction (L) and an arrangement area of ​​the connecting member (6) in the axial direction (L) overlap each other.

[0105] According to this configuration, two elements, the rotating electric machine (1) and the planetary gear mechanism (31) arranged on the first shaft (X1), and two elements, the connecting member (6) and the differential gear mechanism (4) arranged on the second shaft (X2), can be arranged such that the arrangement area of ​​the relatively large-diameter elements in the axial direction (L) overlaps with the arrangement area of ​​the relatively small-diameter elements in the axial direction (L). This makes it easy to keep the axial distance between the first shaft (X1) and the second shaft (X2) short.

[0106] The electric power generating device further includes an inverter device (20) that drives and controls the rotating electric machine (1), It is preferable that at least a portion of the inverter device (20) is disposed radially outside the differential gear mechanism (4).

[0107] According to this configuration, the inverter device (20) can be arranged by utilizing the space radially outside the differential gear mechanism (4), which has a smaller diameter than the second gear (33). This makes it easier to prevent the vehicle drive device (100) from becoming larger due to the arrangement of the inverter device (20).

[0108] The electric power generating device further includes an inverter device (20) that drives and controls the rotating electric machine (1), It is preferable that at least a portion of the inverter device (20) is disposed radially outside the connecting member (6).

[0109] According to this configuration, the inverter device (20) can be arranged by utilizing the space radially outside the connecting member (6), which has a smaller diameter than the differential gear mechanism (4). This makes it easier to prevent the vehicle drive device (100) from becoming larger due to the arrangement of the inverter device (20).

[0110] The electric power generating device further includes an inverter device (20) that drives and controls the rotating electric machine (1), It is preferable that at least a portion of the inverter device (20) is disposed radially outside the planetary gear mechanism (31).

[0111] According to this configuration, the inverter device (20) can be arranged by utilizing the space radially outside the planetary gear mechanism (31), which has a smaller diameter than the rotating electric machine (1). This makes it easier to prevent the vehicle drive device (100) from becoming larger due to the arrangement of the inverter device (20).

[0112] a catch tank (80) for storing oil scooped up by the planetary gear mechanism (31) or the second gear (33), The catch tank (80) is preferably disposed radially outward of the first gear (32).

[0113] According to this configuration, the catch tank (80) can be disposed in the space radially outward of the first gear (32). Therefore, particularly when the first gear (32) is formed to have a smaller diameter than the second gear (33), it is easy to prevent the vehicle drive device (100) from becoming large due to the provision of the catch tank (80).

[0114] The planetary gear mechanism (31) includes a sun gear (SG), a carrier (CR), and a ring gear (RG), the sun gear (SG) is connected to the rotor (12) so as to rotate integrally with the rotor (12); The carrier (CR) rotatably supports a first pinion gear (PG1) and a second pinion gear (PG2) which rotate integrally with each other, The first pinion gear (PG1) meshes with the sun gear (SG), The second pinion gear (PG2) meshes with the ring gear (RG), One of the carrier (CR) and the ring gear (RG) is connected to the first gear (32) so as to rotate integrally with the first gear (32), The other of the carrier (CR) and the ring gear (RG) is preferably fixed to a non-rotating member (NR).

[0115] According to this configuration, the carrier (CR) of the planetary gear mechanism (31) supports the first pinion gear (PG1) and the second pinion gear (PG2) which rotate integrally with each other. The sun gear (SG) which rotates integrally with the rotor (12) meshes with the first pinion gear (PG1). One of the carrier (CR) and the ring gear (RG) is connected to the first gear (32) so as to rotate integrally with the first gear (32), and the other of the carrier (CR) and the ring gear (RG) is fixed to the non-rotating member (NR). The ring gear (RG) meshes with the second pinion gear (PG2). Here, the gear diameters and the number of teeth of the first pinion gear (PG1) and the second pinion gear (PG2) can be set independently. Therefore, according to this configuration, it is easy to ensure a large reduction ratio by the planetary gear mechanism (31) configured as described above without providing a plurality of planetary gear mechanisms. Accordingly, even a small rotating electric machine (1) can transmit a high torque to the output member (2).

[0116] In the above configuration, the ring gear (RG) is fixed to the non-rotating member (NR), It is preferable that the second pinion gear (PG2) is disposed closer to the rotating electric machine (1) in the axial direction (L) than the first pinion gear (PG1).

[0117] Generally, a support member serving as a non-rotating member (NR) is often provided between the rotating electric machine (1) and the planetary gear mechanism (31) in the axial direction (L) to rotatably support the rotor (12). According to this configuration, it is easy to fix the ring gear (RG) meshing with the second pinion gear (PG2) arranged relatively close to the rotating electric machine (1) to the non-rotating member (NR). This makes it easy to realize a configuration in which the ring gear (RG) is fixed to the non-rotating member (NR) while keeping the axial dimension (L) of the vehicle drive device (100) small.

[0118] It is sufficient for the vehicle drive device according to the present disclosure to achieve at least one of the above-mentioned effects. [Industrial Applicability]

[0119] The technology disclosed herein can be utilized in a vehicle drive device that includes a rotating electric machine with a rotor, an output member drivingly connected to wheels, a power transmission mechanism that transmits the rotation of the rotor to the output member, and a differential gear mechanism that distributes the torque transmitted to the output member to a pair of wheels. [Explanation of symbols]

[0120] 100: vehicle drive device, 1: rotating electric machine, 12: rotor, 2: output member, 20: inverter device, 3: power transmission mechanism, 31: planetary gear mechanism, 32: first gear, 33: second gear, 4: differential gear mechanism, 6: transmission shaft (connecting member), 80: catch tank, SG: sun gear, CR: carrier, RG: ring gear, PG1: first pinion gear, PG2: second pinion gear, W: wheel, WT: target wheel, NR: non-rotating member, L: axial direction, L1: first axial side, L2: second axial side, X1: first axis, X2: second axis

Claims

1. A rotating electric machine having a rotor; An output member that is drivingly connected to a wheel of the vehicle; a power transmission mechanism that transmits the rotation of the rotor to the output member; a differential gear mechanism that distributes the torque transmitted to the output member to the pair of wheels, the power transmission mechanism includes a planetary gear mechanism, a first gear, and a second gear; the second gear is in mesh with the first gear and is connected to the output member so as to rotate integrally therewith; A direction along the rotation axis of the rotor is defined as an axial direction, one side in the axial direction is defined as an axial first side, the other side in the axial direction is defined as an axial second side, and one of the pair of wheels that is disposed on the axial first side is defined as a target wheel, The differential gear mechanism is connected to the target wheel via a connecting member, the rotor, the planetary gear mechanism, and the first gear are arranged on a first shaft in the order described above from the first axial direction side to the second axial direction side, the connecting member, the differential gear mechanism, and the second gear are arranged on a second shaft parallel to the first shaft in the order described from the first axial side toward the second axial side, the planetary gear mechanism has a smaller diameter than the rotating electric machine and a larger diameter than the first gear, the differential gear mechanism has a smaller diameter than the second gear and a larger diameter than the connecting member, an inverter device that drives and controls the rotating electric machine; The inverter device includes a power module in which a plurality of elements constituting an inverter circuit are modularized, and a capacitor that smoothes a voltage between positive and negative electrodes on a DC side of the inverter circuit, a vertical dimension of the capacitor is greater than a vertical dimension of the power module; the power module is disposed above the differential gear mechanism and at a position overlapping with the differential gear mechanism as viewed in a vertical direction along the vertical direction; The vehicle drive device, wherein the capacitor is disposed above the connecting member and at a position overlapping with the connecting member when viewed in the vertical direction.

2. A rotating electric machine having a rotor; An output member that is drivingly connected to a wheel of the vehicle; a power transmission mechanism that transmits the rotation of the rotor to the output member; a differential gear mechanism that distributes the torque transmitted to the output member to the pair of wheels, the power transmission mechanism includes a planetary gear mechanism, a first gear, and a second gear; the second gear is in mesh with the first gear and is connected to the output member so as to rotate integrally therewith; A direction along the rotation axis of the rotor is defined as an axial direction, one side in the axial direction is defined as an axial first side, the other side in the axial direction is defined as an axial second side, and one of the pair of wheels that is disposed on the axial first side is defined as a target wheel, The differential gear mechanism is connected to the target wheel via a connecting member, the rotor, the planetary gear mechanism, and the first gear are arranged on a first shaft in the order described above from the first axial direction side to the second axial direction side, the connecting member, the differential gear mechanism, and the second gear are arranged on a second shaft parallel to the first shaft in the order described from the first axial side toward the second axial side, the planetary gear mechanism has a smaller diameter than the rotating electric machine and a larger diameter than the first gear, the differential gear mechanism has a smaller diameter than the second gear and a larger diameter than the connecting member, The planetary gear mechanism includes a sun gear, a carrier, and a ring gear. The sun gear is connected to the rotor so as to rotate integrally with the rotor, the carrier rotatably supports a first pinion gear and a second pinion gear which rotate integrally with each other; the first pinion gear meshes with the sun gear, the second pinion gear has a smaller diameter than the first pinion gear and meshes with the ring gear; one of the carrier and the ring gear is connected to the first gear so as to rotate integrally therewith; the other of the carrier and the ring gear is fixed to a non-rotating member.

3. 3 . The vehicle drive device according to claim 1 , wherein the rotating electric machine and the differential gear mechanism overlap, and the second gear and the planetary gear mechanism overlap, as viewed in the axial direction along the axial direction.

4. an arrangement area of ​​the planetary gear mechanism in the axial direction overlaps with an arrangement area of ​​the differential gear mechanism in the axial direction; The vehicle drive device according to claim 1 or 2, wherein an axial arrangement area of ​​the rotating electric machine and an axial arrangement area of ​​the connecting member overlap with each other.

5. an inverter device that drives and controls the rotating electric machine; The vehicle drive device according to claim 2 , wherein at least a portion of the inverter device is disposed radially outside the differential gear mechanism.

6. an inverter device that drives and controls the rotating electric machine; The vehicle drive device according to claim 2 , wherein at least a portion of the inverter device is disposed radially outward of the connecting member.

7. an inverter device that drives and controls the rotating electric machine; 3. The vehicle drive device according to claim 1, wherein at least a portion of the inverter device is disposed radially outside the planetary gear mechanism.

8. a catch tank that stores oil scooped up by the planetary gear mechanism or the second gear, The vehicle drive device according to claim 1 or 2, wherein the catch tank is disposed radially outward of the first gear.

9. The planetary gear mechanism includes a sun gear, a carrier, and a ring gear. The sun gear is connected to the rotor so as to rotate integrally with the rotor, the carrier rotatably supports a first pinion gear and a second pinion gear which rotate integrally with each other; the first pinion gear meshes with the sun gear, the second pinion gear meshes with the ring gear, one of the carrier and the ring gear is connected to the first gear so as to rotate integrally therewith; 2. The vehicle drive device according to claim 1, wherein the other of the carrier and the ring gear is fixed to a non-rotating member.

10. The ring gear is fixed to the non-rotating member; The vehicle drive device according to claim 2 or 9, wherein the second pinion gear is arranged closer to the rotating electric machine in the axial direction than the first pinion gear.

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