Drive device

Abstract

[Problem] To improve mountability of a drive device including an actuator on a vehicle.　[Solution] A drive device according to the present invention comprises a motor, an inverter, a power transmission mechanism, a parking mechanism, and a housing that accommodates these components. The housing has: a motor accommodation unit; an inverter accommodation unit that accommodates the inverter and is attached to the upper part of the motor accommodation unit in the vertical direction; and a power transmission mechanism accommodation unit that accommodates the power transmission mechanism and is disposed adjacent to the motor accommodation unit in the axial direction of the motor. The power transmission mechanism has: an input shaft into which power from the motor is input; and an output shaft which transmits the power from the motor to drive wheels. The input shaft and the output shaft are disposed side by side in the front-rear direction of a vehicle as viewed in the rotational axis direction. As viewed in the rotational axis direction, the inverter accommodation unit is attached to the upper part on the output shaft side of the motor accommodation unit. As viewed in the rotational axis direction, an actuator of the parking mechanism is disposed at the upper part on the input shaft side of the power transmission mechanism accommodation unit.

Description

Drive unit

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

[0002] Patent Document 1 discloses a drive device that includes an actuator for operating a parking mechanism.

[0003] Japanese Patent Application Laid-Open No. 2018-71679

[0004] The actuator is disposed on the outer periphery of the housing of the drive unit. Therefore, the layout of the drive unit is limited depending on the location of the actuator, which may affect the mountability of the drive unit on the vehicle.

[0005] Therefore, there is a demand for improving the mountability of a drive device equipped with an actuator onto a vehicle.

[0006] A drive device in one aspect of the present invention is a drive device comprising: a motor that is a drive source for a vehicle; an inverter that supplies current to the motor; a power transmission mechanism that transmits power from the motor to drive wheels; a parking mechanism that allows or restricts transmission of the power by the power transmission mechanism; and a housing that accommodates the motor, the inverter, the power transmission mechanism, and the parking mechanism, wherein the housing has: a motor accommodating section that accommodates the motor; an inverter accommodating section that accommodates the inverter and is attached to an upper part of the motor accommodating section in a vertical direction based on an installation state of the drive device on the vehicle; and a power transmission mechanism accommodating section that accommodates the power transmission mechanism and is arranged adjacent to the motor accommodating section in a direction of a rotation axis of the motor, and the power transmission mechanism has: an input shaft to which the power of the motor is input; and an output shaft that transmits the power of the motor to the drive wheels, and the input shaft and the output shaft are arranged side by side in the fore-and-aft direction of the vehicle when viewed in the direction of the rotation axis, When viewed from the direction of the rotational axis, the inverter accommodating section is attached to an upper part of the motor accommodating section on the output shaft side, and when viewed from the direction of the rotational axis, the actuator of the park mechanism is disposed on an upper part of the power transmission mechanism accommodating section on the input shaft side.

[0007] According to an aspect of the present invention, it is possible to improve the mountability of a drive device including an actuator on a vehicle.

[0008] FIG. 1 is a schematic diagram illustrating the arrangement of a drive unit in a vehicle. FIG. 2 is a schematic diagram showing the general configuration of the drive unit. FIG. 3 is a diagram illustrating the drive unit. FIG. 4 is a diagram illustrating the drive unit. FIG. 5 is a diagram illustrating an inverter case. FIG. 6 is a diagram illustrating the inverter case. FIG. 7 is a diagram illustrating the inverter case. FIG. 8 is a diagram illustrating a power transmission mechanism. FIG. 9 is a diagram illustrating a parking mechanism. FIG. 10 is a diagram illustrating the parking mechanism. FIG. 11 is a diagram illustrating the parking mechanism. FIG. 12 is a diagram illustrating the positional relationship between the actuator and the inverter case.

[0009] First, definitions of terms used in this specification will be explained. "Housing" refers to a device that houses a motor, gears, and an inverter. The housing is made up of one or more cases.

[0010] The term "motor" refers to a rotating electric machine having a motor function and / or a generator function.

[0011] When it is stated that an element B (component, part, etc.) is connected to an element A (component, part, etc.), an element B (component, part, etc.) is connected downstream of an element A (component, part, etc.), or an element B (component, part, etc.) is connected upstream of an element A (component, part, etc.), it means that the elements A and B are connected so that power can be transmitted. The power input side is the upstream side, and the power output side is the downstream side. Furthermore, the elements A and B may be connected via another element (a clutch, another gear mechanism, etc.).

[0012] "Overlapping when viewed in a predetermined direction" means that multiple elements are lined up in a predetermined direction, and is synonymous with "overlapping in a predetermined direction." The "predetermined direction" is, for example, the axial direction, the radial direction, the direction of gravity, the vehicle traveling direction (the forward direction of the vehicle, the backward direction of the vehicle), etc. When a drawing shows that multiple elements (components, parts, etc.) are lined up in a predetermined direction, it may be assumed that the description in the specification contains a sentence explaining that they overlap when viewed in the predetermined direction.

[0013] "Not overlapping when viewed in a predetermined direction" and "offset when viewed in a predetermined direction" mean that multiple elements are not lined up in a predetermined direction, and are synonymous with "not overlapping in a predetermined direction" and "offset in a predetermined direction." Examples of the "predetermined direction" include the axial direction, radial direction, gravity direction, and vehicle travel direction (vehicle forward direction, vehicle backward direction). When a drawing shows that multiple elements (components, parts, etc.) are not lined up in a predetermined direction, it may be assumed that the description in the specification includes a sentence explaining that they are not overlapping when viewed in a predetermined direction.

[0014] The phrase "element A (component, part, etc.) is located between element B (component, part, etc.) and element C (component, part, etc.) when viewed from a predetermined direction" means that element A can be observed to be located between element B and element C when viewed from a predetermined direction. The "predetermined direction" is, for example, the axial direction, the radial direction, the direction of gravity, the vehicle traveling direction (the direction in which the vehicle moves forward, the direction in which the vehicle moves backward), etc. For example, if element B, element A, and element C are lined up in this order along the axial direction, it can be said that element A is located between element B and element C when viewed from a radial direction. If a drawing shows that element A is located between element B and element C when viewed from a predetermined direction, it can be considered that the description in the specification includes a sentence explaining that element A is located between element B and element C when viewed from the predetermined direction.

[0015] "Axial direction" refers to the axial direction of the rotation shaft of the component that constitutes the drive device. "Radial direction" refers to the direction perpendicular to the rotation shaft of the component that constitutes the unit. The component is, for example, a motor, a gear mechanism, a differential gear mechanism, etc.

[0016] The present embodiment will be described below. In this embodiment, a drive unit 1 mounted on a vehicle V will be described as an example. FIG. 1 is a schematic diagram illustrating the arrangement of the drive unit 1 in the vehicle V. FIG. 2 is a schematic diagram illustrating the general configuration of the drive unit 1. FIG. 3 is a diagram illustrating the drive unit 1. FIG. 3 is a diagram illustrating the drive unit 1 as seen from the front of the vehicle. FIG. 4 is a diagram illustrating the drive unit 1. FIG. 4 is a diagram illustrating the drive unit 1 as seen from the direction of arrows A-A in FIG. 3. FIG. 5 is a diagram illustrating the inverter case 14. FIG. 5 is a diagram illustrating the drive unit 1 as seen from the direction of arrows B-B in FIG. 3. Note that in FIG. 5, the lid portion 18 is not shown, and the mating surfaces between the case member 11 and the lid portion 18 of the cover member 13 are hatched with different pitches. FIG. 6 is a diagram illustrating the inverter case 14. FIG. 6 is a schematic cross-sectional view of the motor case 10 taken along line A-A in FIG. 5. FIG. 7 is a diagram illustrating the inverter case 14. FIG. 7 is a schematic cross-sectional view of the motor case 10 taken along line B-B in FIG. 5. FIG. 8 is a diagram illustrating the power transmission mechanism 3. FIG. 8 is a schematic cross-sectional view of the housing HS taken along line A-A in FIG. 1. FIG. 8 shows, on the rear side of the vehicle, a region where the intermediate shaft 5 and the input shaft 4 mesh with each other, and on the front side of the vehicle, a region where the intermediate shaft 5 and the final gear 61 of the differential mechanism 6 mesh with each other, with a vertical line VL2 passing through the rotation axis X2 as the boundary. FIG. 9 is a diagram illustrating the parking mechanism 9. FIG. 9 is an enlarged view of region A in FIG. 8. FIG. 10 is a diagram illustrating the parking mechanism 9. FIG. 10 is a schematic cross-sectional view taken along line A-A in FIG. 9. FIG. 11 is a diagram illustrating the parking mechanism 9. FIG. 11 is a schematic cross-sectional view taken along line B-B in FIG. 9. The spring Sp2 that is inserted around the parking rod 92 is not shown in FIG. 11. Fig. 12 is a diagram illustrating the positional relationship between the actuator 97 and the inverter case 14. Fig. 12 is a diagram of the drive unit 1 as seen from the rear of the vehicle. In Fig. 12, the area of ​​the actuator 97 is cross-hatched to make the position of the actuator 97 easier to understand.

[0017] Here, the "up-down direction" in the drawings means the vertical direction when the state in which the drive unit 1 is mounted on the vehicle V is used as a reference. Therefore, when written as "upper side," it means "upper side" in the vertical direction, and when written as "lower side," it means "lower side" in the vertical direction. Furthermore, the "front-rear direction" means the front-rear direction of the vehicle when the state in which the drive unit 1 is mounted on the vehicle V is used as a reference. Therefore, when written as "front side," it means "front side" in the front-rear direction of the vehicle, and when written as "rear side," it means "rear side" in the front-rear direction of the vehicle.

[0018] As shown in Fig. 1, the drive unit 1 is mounted on the rear side of the vehicle V. A battery BT is provided in front of the drive unit 1. The drive unit 1 is disposed between frames FR, FR that are spaced apart in the front-to-rear direction. The frames FR, FR are oriented along the vehicle width direction.

[0019] 1 and 2, the drive unit 1 includes a motor 2 as a drive source, a power transmission mechanism 3 that transmits the rotation of the motor 2 to the left and right drive wheels WH, and an inverter INV that converts the power of a battery BT and supplies current to the motor 2. The battery BT and the inverter INV are connected by a cable Ca. The drive unit 1 also includes a parking mechanism 9 that allows or restricts the transmission of rotation by the power transmission mechanism 3. The drive unit 1 also includes a housing HS that accommodates the motor 2, the power transmission mechanism 3, the inverter INV, and the parking mechanism 9.

[0020] The housing HS has a motor case 10 (motor housing) that houses the motor 2, a gear case 12 (power transmission mechanism housing) that houses the power transmission mechanism 3, and an inverter case 14 (inverter housing) that houses the inverter INV. The gear case 12 is provided adjacent to the motor case 10 from the left side in the vehicle width direction (the lower side in FIG. 1 ). The inverter case 14 is provided in a position that overlaps with the motor case 10 when viewed from above.

[0021] 2, in the drive unit 1, the rotational driving force of the motor 2 is transmitted to a power transmission mechanism 3. The power transmission mechanism 3 has an input shaft 4 that rotates integrally with the motor 2, an intermediate shaft 5 that reduces the rotation of the input shaft 4 and transmits it to a differential mechanism 6, and drive shafts 7 (7A, 7B) that transmit the rotation of the differential mechanism 6 to the left and right drive wheels WH, WH.

[0022] 10 , the input shaft 4 has a shaft portion 40 that is provided coaxially with the motor shaft 20 of the motor 2, and a gear portion 41 that is formed on the outer periphery of the shaft portion 40. The shaft portion 40 is spline-fitted with the motor shaft 20, and rotates integrally with the motor shaft 20 around the rotation axis X1.

[0023] 10, a park gear 90, which will be described later, is provided on the outer periphery of the shaft portion 40. The park gear 90 is spline-fitted to the shaft portion 40 and rotates integrally with the shaft portion 40 around the rotation axis X1.

[0024] 2, the intermediate shaft 5 has a shaft portion 50 that extends along a rotation axis X2 that is parallel to the rotation axis X1, and two gear portions (a large-diameter gear portion 51 and a small-diameter gear portion 52) that are provided on the outer periphery of the shaft portion 50 and have different diameters. The large-diameter gear portion 51 and the small-diameter gear portion 52 rotate integrally with the shaft portion 50 around the rotation axis X2. The gear portion 41 of the input shaft 4 meshes with the large-diameter gear portion 51 of the intermediate shaft 5.

[0025] A final gear 61 of the differential mechanism 6 meshes with the small-diameter gear portion 52 of the intermediate shaft 5. The final gear 61 is fixed to the outer periphery of the differential case 60 and rotates integrally with the differential case 60 around a rotation axis X3. The rotation axis X3 is parallel to the rotation axes X1 and X2. The differential case 60 is connected to the drive shafts 7 (7A, 7B) via bevel gears 62 and side gears 63. Therefore, the drive shafts 7 (7A, 7B) rotate together with the final gear 61 around the rotation axis X3. In other words, the differential mechanism 6 and the drive shafts 7 (7A, 7B) constitute the output shaft 8 of the drive unit 1.

[0026] In the drive unit 1, the rotation axis X1 of the motor shaft 20 and the input shaft 4, the rotation axis X2 of the intermediate shaft 5, and the rotation axis X3 of the output shaft 8 are arranged in this order from the rear to the front in the fore-and-aft direction.

[0027] 2, these rotation axes X1 to X3 are oriented along the vehicle width direction. Note that, hereinafter, these rotation axes X1 to X3 may also be collectively referred to as rotation axis X as necessary.

[0028] As shown in Figure 2, the motor case 10 has a case member 11 and a cover member 13 joined together in the direction of the rotation axis X. The case member 11 has a support wall portion 111 that surrounds the rotation axis X1. The support wall portion 111 is oriented along the rotation axis X1. The motor 2 is housed inside the support wall portion 111. The gear case 12 is connected to one end 111a of the support wall portion 111 with a bolt (not shown). The cover member 13 is connected to the other end 111b of the support wall portion 111 with a bolt (not shown).

[0029] A wall portion 112 is provided on one end 111a of the support wall portion 111, extending radially inward between the motor 2 and the power transmission mechanism 3. The wall portion 112 is provided in a direction perpendicular to the rotation axis X1.

[0030] The space formed inside the motor case 10 and the gear case 12 is divided into two by a wall 112. The space on the motor 2 side from the wall 112 (on the right side in the figure) is a motor chamber Sa that houses the motor 2. The space on the power transmission mechanism 3 side from the wall 112 (on the left side in the figure) is a gear chamber Sb that houses the power transmission mechanism 3.

[0031] 10, an opening 112a is provided in a region intersecting the rotation axis X1 in the wall portion 112. The motor shaft 20 passes through the opening 112a of the wall portion 112 in the direction of the rotation axis X1.

[0032] The wall portion 112 is provided with a cylindrical wall portion 113 surrounding the opening 112a. The cylindrical wall portion 113 protrudes on both the surface on the motor chamber Sa side (right side in the drawing) and the surface on the gear chamber Sb side in the direction of the rotation axis X1.

[0033] A bearing Bm is provided on the inner periphery of the cylindrical wall portion 113 on the motor chamber Sa side. One end 20a of the motor shaft 20 is supported by the cylindrical wall portion 113 via the bearing Bm. A bearing B4 is provided on the inner periphery of the cylindrical wall portion 113 on the gear chamber Sb side. The other end 40b of the shaft portion 40 of the input shaft 4 is supported by the cylindrical wall portion 113 via the bearing B4. In this state, the outer periphery of the one end 20a of the motor shaft 20 is spline-fitted to the inner periphery of the other end 40b of the shaft portion 40.

[0034] 2, a cylindrical wall portion 114 is provided on the surface of the wall portion 112 facing the power transmission mechanism 3 (left side in the figure), forward of the rotation axis X1. The cylindrical wall portion 114 has a cylindrical shape that surrounds the rotation axis X2. A bearing B5 is provided on the inner periphery of the cylindrical wall portion 114. The bearing B5 supports the shaft portion 50 of the intermediate shaft 5.

[0035] 2, the case member 11 has a bulging wall portion 15 that bulges forward from the support wall portion 111. The differential mechanism 6 is housed inside the bulging wall portion 15. The bulging wall portion 15 has a side wall portion 151 that extends along the rotation axis X3. One end 151a and the other end 151b of the side wall portion 151 in the direction of the rotation axis X3 are flush with one end 111a and the other end 111b of the support wall portion 111, respectively.

[0036] The gear case 12 is connected to one end 151a of the side wall portion 151 in the direction of the rotation axis X3 with a bolt (not shown). A connecting wall 152 that connects the side wall portion 151 and the support wall portion 111 is provided at the other end 151b of the side wall portion 151. The connecting wall 152 is provided in a direction perpendicular to the rotation axis X3.

[0037] The drive shaft 7A passes through the connecting wall 152 in the direction of the rotation axis X3 through a region where the connecting wall 152 intersects with the rotation axis X3. A cylindrical drive shaft support portion 153 that surrounds the drive shaft 7A is provided on the connecting wall 152. A bearing B7 is supported on the inner periphery of the drive shaft support portion 153. The drive shaft 7A is supported by the drive shaft support portion 153 via the bearing B7.

[0038] In addition, in the bulging wall portion 15, a connecting wall portion 154 is provided between one end 151 a and the other end 151 b of the side wall portion 151, connecting the side wall portion 151 and the support wall portion 111. The connecting wall portion 154 is provided in a direction perpendicular to the rotation axis X3.

[0039] The support cylinder 601 of the differential case 60 penetrates the connecting wall portion 154 in the direction of the rotation axis X3 through an area where the connecting wall portion 154 intersects with the rotation axis X3. The connecting wall portion 154 has a cylindrical differential case support portion 155 that surrounds the support cylinder 601. A bearing B6 is supported on the inner periphery of the differential case support portion 155. The support cylinder 601 of the differential case 60 is supported by the differential case support portion 155 via the bearing B6.

[0040] The gear case 12 has a bottom wall portion 120 provided in a direction perpendicular to the rotation axes X1 to X3, and a peripheral wall portion 121 that surrounds the entire outer periphery of the bottom wall portion 120. A tip surface 121a of the peripheral wall portion 121 has a rear side in the front-to-rear direction joined to one end 111a of the support wall portion 111, and a front side joined to one end 151a of the side wall portion 151 of the bulging wall portion 15.

[0041] A bearing B4 is provided in a region of the bottom wall portion 120 where the rotation axis X1 intersects. The bearing B4 supports one end 40a of the shaft portion 40 of the input shaft 4 (see FIG. 10 ). As a result, both ends of the input shaft 4 in the direction of the rotation axis X1 are supported by the case member 11 side and the gear case 12 side, and the input shaft 4 is provided rotatable about the rotation axis X1.

[0042] 2, a bearing B5 is provided in a region of the bottom wall portion 120 where the rotation axis X2 intersects. The bearing B5 supports the shaft portion 50 of the intermediate shaft 5. As a result, both ends of the intermediate shaft 5 in the direction of the rotation axis X2 are supported by the case member 11 side and the gear case 12 side, and the intermediate shaft 5 is provided rotatable about the rotation axis X2.

[0043] The support cylinders 602 of the differential case 60 penetrate the area of ​​the bottom wall portion 120 where the rotation axis X3 intersects with the bottom wall portion 120 in the direction of the rotation axis X3. A cylindrical differential case support portion 122 is provided in the bottom wall portion 120 and surrounds the support cylinders 602. A bearing B6 is supported on the inner periphery of the differential case support portion 122. The support cylinders 602 of the differential case 60 are supported by the differential case support portion 122 via the bearing B6. As a result, both ends of the differential case 60 in the direction of the rotation axis X3 are supported by the motor case 10 (case member 11) side and the gear case 12 side, and the differential case 60 is provided rotatable about the rotation axis X3.

[0044] Drive shafts 7A and 7B are inserted through the inner peripheries of support cylinders 601 and 602 of the differential case 60. The rotation of the differential case 60 is transmitted to the drive shafts 7A and 7B via a bevel gear 62 and a side gear 63. Therefore, in conjunction with the rotation of the differential case 60, the drive shafts 7A and 7B also rotate around the rotation axis X3.

[0045] The cover member 13 has a wall portion 130 perpendicular to the rotation axis X1 and a peripheral wall portion 131 surrounding the outer periphery of the wall portion 130. One end 131a of the peripheral wall portion 131 is joined to the other end 111b of the support wall portion 111 of the case member 11 from the direction of the rotation axis X1. In this state, the opening of the case member 11 on the side of the other end 111b is closed by the cover member 13.

[0046] The cover member 13 has a motor support portion 135 provided on the surface of the wall portion 130 facing the motor chamber Sa. The motor support portion 135 is cylindrical and surrounds the rotation axis X1 with a gap therebetween. A bearing Bm is supported on the inner periphery of the motor support portion 135. The outer periphery of the motor shaft 20 is supported by the motor support portion 135 via the bearing Bm.

[0047] The motor 2 has a motor shaft 20, a cylindrical rotor 21 fitted onto the motor shaft 20, and a stator 22 that surrounds the outer periphery of the rotor 21 with a gap between them. Bearings Bm, Bm are fitted onto the motor shaft 20 on one side and the other side of the rotor 21 in the direction of the rotation axis X1. The motor shaft 20 is rotatably supported by the motor case 10 via the bearings Bm, Bm. The stator 22 is inserted into the inner periphery of the support wall portion 111.

[0048] 3, an inverter case 14 that houses an inverter INV is provided on top of the motor case 10. The inverter case 14 is provided across the case member 11 and the cover member 13 in the direction of the rotation axis X, and is provided at a position separated from the gear case 12. This makes it easier for the inverter case 14 to avoid interference with an actuator 97, which is disposed on top of the gear case 12 (described later), without reducing the volume.

[0049] As shown in Fig. 3 , the inverter case 14 is formed by joining a support wall 16 on the case member 11 side and a support wall 17 on the cover member 13 side, and closing the opening with a lid 18 that straddles the support wall 16 and the support wall 17. As shown in Fig. 5 , when viewed from above in the vertical direction, the support wall 16 is provided in a range that extends from the area where the motor 2 is disposed (near the rotation axis X1), across the area where the intermediate shaft 5 is disposed (the rotation axis X2), to the area where the output shaft 8 is disposed (the rotation axis X3). Therefore, as shown in Figs. 6 and 7 , the inverter case 14 is positioned so as to overlap the motor 2 and the output shaft 8 when viewed from above.

[0050] 3, the support wall 16 of the case member 11 is provided on the upper part of the bulging wall 15 that bulges out from the case member 11 toward the front side of the page. As shown in FIG. 5, when viewed from above in the vertical direction, the support wall 16 is a continuous wall made up of a first wall 161, a second wall 162, and a third wall 163.

[0051] The first wall portion 161 is disposed in a position offset from the cover member 13 toward the gear case 12 (to the right in the figure) and oriented along the front-to-rear direction (up-and-down direction in the figure). The first wall portion 161 is provided in a range that crosses the area overlapping with the bulging wall portion 15 in the front-to-rear direction. The second wall portion 162 extends from the front end of the first wall portion 161 toward the cover member 13 in the direction of the rotation axis X. The third wall portion 163 extends from the rear end of the first wall portion 161 toward the cover member 13 in the direction of the rotation axis X. When viewed from above, the rear end of the third wall portion 163 is connected to the first wall portion 161 in the area where it overlaps with the support wall portion 111. The second wall portion 162 and the third wall portion 163 are provided and oriented along the direction of the rotation axis X.

[0052] 6, in a region of the third wall portion 163 that overlaps with the support wall portion 111, the tip surface 163a of the third wall portion 163 in the direction of the rotation axis X is flush with the other end 111b of the support wall portion 111. As shown in FIG. 7, in a region of the third wall portion 163 that overlaps with the bulging wall portion 15, the tip surface 163a of the third wall portion 163 in the direction of the rotation axis X is also flush with the other end 151b of the side wall portion 151 of the bulging wall portion 15.

[0053] 5, the tip surface 162a of the second wall portion 162 and the tip surface 163a of the third wall portion 163 are aligned in the direction of the rotation axis X. The tip surfaces 162a and 163a are flush with each other. Therefore, the tip surface 162a of the second wall portion 162, the tip surface 163a of the third wall portion 163, the other end 111b of the support wall portion 111 (see FIG. 6), and the other end 151b of the side wall portion 151 of the bulging wall portion 15 (see FIG. 7) are located on the same plane along the mating surfaces of the case member 11 and the cover member 13.

[0054] 4 , when viewed from the direction of the rotation axis X, the cover member 13 has a support wall portion 17 that bulges forward from the area of ​​the peripheral wall portion 131. Specifically, the support wall portion 17 is provided in an area forward of a vertical line VL1 passing through the rotation axis X1 and above a horizontal line HL1 passing through the rotation axis X1. When viewed from the direction of the rotation axis X, the support wall portion 17 is provided in a position that overlaps with the support wall portion 16 of the case member 11 but does not overlap with the drive shaft 7A (a position offset upward from the drive shaft 7A).

[0055] 5, the cover member 13 has an extending wall portion 132 extending forward from a peripheral wall portion 131. When viewed from above in the vertical direction, the extending wall portion 132 overlaps with the rotation axis X3.

[0056] When viewed from above in the vertical direction, the support wall portion 17 is a continuous wall composed of a first wall portion 171, a second wall portion 172, and a third wall portion 173. The first wall portion 171 is disposed in a position offset from the case member 11 toward the opposite side of the gear case 12 (left side in the drawing) and oriented along the front-rear direction (up-down direction in the drawing). The first wall portion 171 is provided in a range that crosses the extending wall portion 132 in the front-rear direction. The rear end of the first wall portion 171 extends toward the peripheral wall portion 131.

[0057] The second wall portion 172 extends from the front end of the first wall portion 171 toward the case member 11 in the direction of the rotation axis X. The third wall portion 173 extends from the rear end of the first wall portion 171 toward the case member 11 in the direction of the rotation axis X. The second wall portion 172 and the third wall portion 173 are provided oriented along the direction of the rotation axis X.

[0058] As shown in Fig. 6, a tip surface 173a of the third wall portion 173 in the direction of the rotation axis X is provided flush with one end 131a of the peripheral wall portion 131. As shown in Fig. 7, a tip surface 173a of the third wall portion 173 in the direction of the rotation axis X is provided flush with one end 132a of the extending wall portion 132.

[0059] As shown in Figure 5, the tip surface 172a of the second wall portion 172 and the tip surface 173a of the third wall portion 173 are aligned in the direction of the rotation axis X. The tip surfaces 172a and 173a are flush with each other. Therefore, the tip surface 172a of the second wall portion 172, the tip surface 173a of the third wall portion 173, one end 131a of the peripheral wall portion 131 (see Figure 6), and one end 132a of the extending wall portion 132 (see Figure 7) are located on the same plane along the mating surfaces of the case member 11 and the cover member 13.

[0060] As shown in FIG. 5 , when the case member 11 and the cover member 13 are joined in the direction of the rotation axis X, a tip surface 162a of the second wall portion 162 of the support wall portion 16 abuts against a tip surface 172a of the second wall portion 172 of the support wall portion 17. A tip surface 163a of the third wall portion 163 of the support wall portion 16 abuts against a tip surface 173a of the third wall portion 173 of the support wall portion 17. As shown in FIG. 6 , the other end 111b of the support wall portion 111 abuts against one end 131a of the peripheral wall portion 131. As shown in FIG. 7 , the other end 151b of the side wall portion 151 of the bulging wall portion 15 abuts against one end 132a of the extending wall portion 132. As a result, a space Sc surrounded by the support walls 16 and 17 is formed in the motor case 10.

[0061] 6 and 7 , the upper end surface 16a of the support wall portion 16 is flush with the upper end surface 17a of the support wall portion 17. The joining surface 18a of the lid portion 18 is joined without any gaps to the upper end surfaces 16a, 17a of the support walls 16, 17. Therefore, the opening of the space Sc surrounded by the support walls 16, 17 is closed by the lid portion 18.

[0062] As a result, a space Sc surrounded by the support walls 16, 17 and the lid 18 of the motor case 10 is formed inside the inverter case 14, and the inverter INV (see FIG. 5) is housed in the space Sc. In the following description, the space Sc is also referred to as an inverter chamber Sc.

[0063] As shown in FIG. 8 , when viewed from the direction of the rotation axis X, the peripheral wall portion 121 of the gear case 12 surrounding the gear chamber Sb has a ceiling portion 121t that crosses the upper side of the input shaft 4, the intermediate shaft 5, and the output shaft 8 in the front-to-rear direction, a bottom portion 121b that crosses the lower side in the front-to-rear direction, and side walls 121c and 121d that connect the ends of the ceiling portion 121t and the bottom portion 121b.

[0064] In this embodiment, the input shaft 4, the intermediate shaft 5, and the output shaft 8 are arranged in this order from rear to front as viewed from the direction of the rotation axis X. That is, the intermediate shaft 5 is provided between the input shaft 4 and the output shaft 8. The radius r1 of the gear portion 41 of the input shaft 4 is smaller than the radius r2 of the large-diameter gear portion 51 of the intermediate shaft 5 (r1<r2). The radius r3 of the final gear 61 of the output shaft 8 is larger than the radius r9 of the park gear 90 of the input shaft 4 (r3>r9).

[0065] Furthermore, a horizontal line HL3 passing through the rotation axis X3 (shaft center) of the output shaft 8 and a horizontal line HL1 passing through the rotation axis X1 (shaft center) of the input shaft 4 are located below a horizontal line HL2 passing through the rotation axis X2 (shaft center) of the intermediate shaft 5. Therefore, when viewed from the direction of the rotation axis X, the shape of the ceiling portion 121t of the peripheral wall portion 121 is shaped along a tangent passing through the outer periphery of the park gear 90 of the input shaft 4 and the outer periphery of the large-diameter gear portion 51 of the intermediate shaft 5, and a tangent passing through the outer periphery of the large-diameter gear portion 51 of the intermediate shaft 5 and the final gear 61 of the output shaft 8. This allows the region of the ceiling portion 121t that overlaps with the intermediate shaft 5 in the vertical direction (the region above the intermediate shaft 5) to be positioned offset upward from the regions that overlap with the input shaft 4 and the output shaft 8 in the vertical direction (regions that do not overlap with the intermediate shaft 5 in the vertical direction).

[0066] As a result, when viewed from the direction of the rotation axis X, the gear case 12 has spatial margins with a range in the up-down direction above the output shaft 8 and to the side of the intermediate shaft 5 (left side in FIG. 8 ) and above the input shaft 4 and to the side of the intermediate shaft 5 (right side in FIG. 8 ).

[0067] A cable Ca is connected from the battery BT to the inverter INV inside the inverter case 14 (see FIG. 1). A connection portion 14c for connecting the cable Ca is provided on the lid portion 18 of the inverter case 14. The connection portion 14c is a hole that opens on the side surface of the lid portion 18 facing the gear case 12 in the direction of the rotation axis X. The connection portion 14c communicates with the inverter chamber Sc (see FIG. 12).

[0068] 8, when viewed from the direction of the rotation axis X, the ceiling portion 121t of the gear case 12 has an area above the output shaft 8 that is inclined downward as it moves forward (left side in the figure) from the intermediate shaft 5. When viewed from the direction of the rotation axis X, the connection portion 14c opens outside the ceiling portion 121t in an area above the output shaft 8 and forward of the intermediate shaft 5. This allows the cable Ca (see FIG. 1) that connects the inverter INV and the battery BT to be routed using the space above the output shaft 8 in the gear case 12.

[0069] Furthermore, the connection portion 14c is provided on the opposite side of the intermediate shaft 5 from the actuator 97 of the parking mechanism 9 when viewed from the direction of the rotation axis X. Therefore, the cable Ca connected from the connection portion 14c to the inverter INV does not interfere with the actuator 97 either.

[0070] An actuator 97 of the parking mechanism 9 is provided in a space formed above the input shaft 4 in the gear case 12. As shown in Fig. 9, the parking mechanism 9 has a parking gear 90, a parking pole 91, a parking rod 92, a support 93, a detent spring 94, a manual plate 95, a manual shaft 96, and an actuator 97 (see Fig. 8).

[0071] The park gear 90 rotates around the rotation axis X1 integrally with the shaft portion 40 of the input shaft 4. The park gear 90 has teeth 901 and tooth grooves 902 alternately arranged in the circumferential direction around the rotation axis X1.

[0072] A park pole 91, a park rod 92, a support 93, a detent spring 94, and a manual plate 95 are located below the park gear 90. A manual shaft 96 is provided at the rear of the park gear 90. The manual shaft 96 is provided so as to cross the rotation axis X1 in the vertical direction. As shown in FIG. 8 , an upper end 96a of the manual shaft 96 passes through a through-hole 125b of the gear case 12 and is located outside the gear case 12. An actuator 97 is connected to the upper end 96a of the manual shaft 96.

[0073] As shown in Figure 9, the park pole 91 has a long, plate-shaped base 910 oriented along a straight line Lm. The straight line Lm is a straight line extending in the front-to-rear direction. A support pin P penetrates the base 910. The support pin P is located behind the rotation axis X1 and below the horizontal line HL1.

[0074] The support pin P is provided in a direction along the axis Xa that is parallel to the rotation axis X1. The support pin P is fixed to the wall portion 112 of the case member 11. As a result, the park pole 91 is supported by the support pin P so as to be rotatable around the axis Xa.

[0075] A claw portion 912 protruding from the upper surface 910a is provided at a position where the base portion 910 intersects with a vertical line VL1 passing through the rotation axis X1. The claw portion 912 faces the tooth groove portion 902 of the park gear 90 in the direction of the vertical line VL1.

[0076] An operating portion 911 protruding from the lower surface 910b is provided on the base portion 910 forward of the claw portion 912 in the direction of the straight line Lm. The operating portion 911 is placed on a cam 920 supported by a support 93.

[0077] Here, a torsion spring Sp1 is fitted onto the support pin P. One end Spa of the torsion spring Sp1 is in pressure contact with the upper surface 910a of the base 910 on the front side as viewed from the support pin P. The other end Spb of the torsion spring Sp1 is engaged with an engaging groove 112c provided in the wall portion 112 on the rear side as viewed from the support pin P.

[0078] In this state, the torsion spring Sp1 applies a biasing force to the park pole 91. The park pole 91, which can rotate around the axis Xa, is constantly biased by the biasing force of the torsion spring Sp1 in a direction that moves the claw portion 912 away from the park gear 90 (counterclockwise in FIG. 9 : see the arrow).

[0079] As shown in Figure 9, the parking rod 92 is oriented along a straight line Ln when viewed from the direction of the rotation axis X1. The straight line Ln is a straight line that runs along the lower side of the parking pole 91 in the longitudinal direction of the vehicle. The parking rod 92 is oriented such that the tip end, onto which the cam 920 is inserted, faces the parking pole 91 (front side). The cam 920 is inserted between the support 93 and the operating portion 911 of the parking pole 91.

[0080] As shown in FIG. 10, in a cross-sectional view, the support 93 has a base portion 930 on which the cam 920 is placed, and a side wall portion 931 provided between the cam 920 and the wall portion 112 in the direction of the rotation axis X1.

[0081] The support 93 is fixed to the mounting portion 112b of the wall portion 112 with bolts B, B passing through the base portion 930 and the side wall portion 931, with the detent spring 94 sandwiched therebetween. The mounting portion 112b is a portion of the wall portion 112 formed to be thick.

[0082] Here, a rib 129 is provided on the bottom wall 120 of the gear case 12 on the opposite side of the side wall 931 with the cam 920 sandwiched between them in the direction of the rotation axis X1. The rib 129 protrudes from the bottom wall 120 toward the cam 920 in the direction of the rotation axis X1. As a result, the cam 920 is sandwiched between the side wall 931 and the rib 129 on both sides in the direction of the rotation axis X1, preventing it from falling off the base 930.

[0083] In this state, in the parking mechanism 9, the input shaft 4, the parking gear 90, the parking pole 91, the cam 920, and the support 93 are arranged in order from the inner diameter side to the outer diameter side of the rotation axis X1.

[0084] 9, the base 930 is provided with a cam portion 935 (on the left side in the figure) at a position facing the operating portion 911 of the park pole 91 in the vertical direction. An upper surface 935a of the cam portion 935 is located forward and above an upper surface 930a of the base 930.

[0085] A cam 920 is fitted onto the tip 92a side of the parking rod 92. The cam 920 is biased toward the tip 92a by the biasing force of a spring Sp2. When the parking rod 92 is displaced in a direction (indicated by the left-pointing arrow in FIG. 9 ) in which the cam 920 is pushed into the space between the support 93 and the operating portion 911 of the parking pole 91, the cam 920 riding on the cam portion 935 pushes up the operating portion 911.

[0086] 9, the park pole 91 is positioned so that the claw portion 912 is engaged with the tooth groove portion 902 of the park gear 90. Therefore, the rotation of the park gear 90 and the input shaft 4, which rotates integrally with the park gear 90, around the rotation axis X1 is restricted.

[0087] When the parking rod 92 is displaced in the direction of being pulled out from between the support 93 and the operating portion 911 of the parking pole 91 (in the direction of the right-pointing arrow in Figure 9), the cam 920 of the parking rod 92 descends down the cam portion 935 and reaches the upper surface 930a of the base 930.

[0088] 9 due to the biasing force of the torsion spring Sp1, the park pole 91 is positioned so that the claw portion 912 is disengaged from the tooth groove portion 902 of the park gear 90. This allows rotation of the park gear 90 and the input shaft 4, which rotates integrally with the park gear 90, about the rotation axis X1. In this way, the park pole 91 is configured to switch (disengage) between a state in which it is engaged with the tooth groove portion 902 (outer periphery) of the park gear 90 and a state in which it is disengaged from the tooth groove portion 902.

[0089] 11, a base end 92b of the parking rod 92 is supported by a manual plate 95. In this state, the parking rod 92 is prevented from falling off the manual plate 95 and is provided so as to be displaceable in the direction of a straight line Ln.

[0090] The manual plate 95 has a base 951 that is fitted onto the manual shaft 96, and an arm 952 and an engagement portion 953 that extend from the outer periphery of the base 951 in the radial direction of the rotation axis Y of the manual shaft 96. A base end 92b of the park rod 92 is supported by the arm 952 of the manual plate 95.

[0091] The engaging portion 953 has a plurality of recesses formed on its outer periphery, which are continuous in the circumferential direction around the rotation axis Y of the manual shaft 96. A roller 941 of the detent spring 94 is elastically engaged with one of these recesses.

[0092] As shown in FIG. 9 , the manual shaft 96 penetrates the base 951 of the manual plate 95 in the vertical direction. The rotation axis Y of the manual shaft 96 is oriented along the vertical direction. The lower end 96b of the manual shaft 96 is inserted into the support cylinder 127. The support cylinder 127 is provided on the bottom 121b of the peripheral wall 121 of the gear case 12. As shown in FIG. 8 , the manual shaft 96 extends in the vertical direction on the side opposite to the output shaft 8 as viewed from the input shaft 4. The upper end 96a of the manual shaft 96 penetrates the peripheral wall 121 of the gear case 12 and is exposed to the outside of the gear case 12.

[0093] An upper end 96a of the manual shaft 96 is connected to a drive motor (not shown) of an actuator 97. For example, in conjunction with switching between the driving mode and the parking mode of the vehicle, the actuator 97 rotates the manual shaft 96 around a rotation axis Y (in the direction of the arrow in FIG. 9 ).

[0094] 11 , when the manual shaft 96 rotates, the manual plate 95 fixed to the manual shaft 96 also rotates around the rotation axis Y. As a result, the park rod 92 supported by the manual plate 95 is displaced in the direction of the straight line Ln in conjunction with the rotation of the manual plate 95.

[0095] In conjunction with the displacement of the park rod 92 in the direction of the line Ln, the cam 920 rotates the park pole 91 about the axis Xa (see FIG. 9). As a result, the claws 912 of the park pole 91 engage with and disengage from the tooth grooves 902 of the park gear 90, thereby restricting or allowing rotation of the park gear 90. That is, in the park mechanism 9 according to this embodiment, the actuator 97 controls whether the park pole 91 engages with or disengages from the park gear 90.

[0096] 8 , the area of ​​the ceiling portion 121t of the peripheral wall portion 121 that overlaps with the intermediate shaft 5 in the up-down direction is the highest peak T. In this embodiment, the actuator 97 of the parking mechanism 9 is disposed at a position rearward (to the right in the drawing) from the peak T of the ceiling portion 121t. In other words, the actuator 97 is provided above the input shaft 4 and to the side of the intermediate shaft 5.

[0097] Specifically, a recess 125 is formed in the ceiling portion 121t in an area above the input shaft 4 and to the side of the intermediate shaft 5. The recess 125 has a bottom surface 125a that is lower than the top T by a depth Ha.

[0098] Here, a spatial margin is generated above the input shaft 4 and to the side of the intermediate shaft 5, the size of which is determined by the outer diameter (radius r2) of the large-diameter gear portion 51 of the intermediate shaft 5. The recess 125 is formed by recessing the outer periphery of the gear case 12 so as to fill this marginal space.

[0099] A through-hole 125b that passes through the ceiling portion 121t in the vertical direction is opened in a bottom surface 125a of the recess 125. In this embodiment, the actuator 97 of the parking mechanism 9 is disposed in the recess 125, and the manual shaft 96 passes through the through-hole 125b.

[0100] Furthermore, a protruding wall 123 that protrudes upward is provided at the connection between the rear end of the recess 125 and the side wall 121d. As shown in Fig. 12, the protruding wall 123 is provided so as to surround the outer periphery of the recess 125. The actuator 97 is fixed to the protruding wall 123 with a bolt B.

[0101] Here, if the ceiling portion 121t is at the same height as the top portion T over the entire length in the front-to-rear direction, and the actuator 97 is provided on the ceiling portion 121t, the upper end 97t of the actuator 97 may protrude above the upper end 14t of the inverter case 14. In this case, the layout of the drive unit 1 in the vehicle V is limited to an arrangement in which the protruding actuator 97 does not interfere with other components of the vehicle, which affects the mountability on the vehicle.

[0102] 8, the present embodiment employs an arrangement in which the input shaft 4 engages with the intermediate shaft 5 from below. This provides a space above the input shaft 4 on the ceiling portion 121t, and a recess 125 recessed below the top T is provided in this space, allowing the actuator 97 to be disposed in the recess 125.

[0103] 12, the upper end 97t of the actuator 97 can be positioned lower than the upper end 14t of the inverter case 14 by a height Hb. Therefore, the actuator 97 does not protrude above the inverter case 14. This makes it less likely that the actuator 97 will interfere with other components of the vehicle, improving the mountability of the drive unit 1 on the vehicle.

[0104] Furthermore, in this embodiment, as shown in FIG. 9, a park pole 91, a park rod 92, a support 93, a detent spring 94, and a manual plate 95 are provided below the park gear 90.

[0105] As shown in FIG. 8 , in the gear case 12, a spatial margin is provided below the input shaft 4 and to the side of the output shaft 8, the size of which is determined by the outer diameter (radius r3) of the final gear 61 of the output shaft 8. In this embodiment, this spatial margin is utilized to arrange the park pole 91, the park rod 92, the support 93, the detent spring 94, and the manual plate 95. As a result, there is no need to provide additional space in the gear case 12 for accommodating the park pole 91, the park rod 92, the support 93, the detent spring 94, and the manual plate 95. If additional space were provided separately, there is a possibility that the drive unit 1 would be increased in size in the vertical direction. As described above, the spatial margin provided below the input shaft 4 within the gear case 12 reduces the possibility that the drive unit 1 would be increased in size in the vertical direction.

[0106] Furthermore, by providing the park pole 91, park rod 92, support 93, detent spring 94, and manual plate 95 below the park gear 90, no components of the park mechanism 9 are positioned between the input shaft 4 and the ceiling 121t in the vertical direction. This allows the vertical depth Ha of the recess 125 in which the actuator 97 is disposed to be made deeper.

[0107] 12, a portion of the actuator 97 extends toward the case member 11 in the direction of the rotation axis X. Therefore, the actuator 97 partially overlaps with the inverter case 14 when viewed from the front-rear direction.

[0108] 8, if the inverter case 14 is disposed so as to extend from the output shaft 8 side to a range that intersects the input shaft 4 (rotation axis X1) when viewed in the direction of the rotation axis X, it may be necessary to dispose the actuator 97 so that it protrudes above the inverter case 14 in order to avoid interference with the inverter case 14. In such a case, the vertical height of the drive unit 1 increases by the amount of protrusion of the actuator 97, which may affect the mountability of the drive unit 1 on the vehicle V.

[0109] Therefore, in this embodiment, as shown in Fig. 8, when viewed from the direction of the rotation axis X, the inverter case 14 is disposed closer to the output shaft 8 (rotation axis X3) in the front-to-rear direction, thereby ensuring space for disposing the actuator 97 on the input shaft 4 side. This eliminates the need to provide the actuator 97 protruding above the inverter case 14, reducing the possibility that the height of the drive unit 1 in the vertical direction will increase due to the provision of the actuator 97. This increases the degree of freedom in the layout of the drive unit 1, and is expected to improve the ease of installation in the vehicle V.

[0110] Furthermore, the motor case 10 and the gear case 12 are adjacent to each other in the direction of the rotation axis X. Therefore, by disposing the inverter case 14 on top of the motor case 10 and disposing the actuator 97 on top of the gear case 12, the inverter case 14 and the actuator 97 can be disposed with their positions offset in the direction of the rotation axis X. This reduces the possibility of interference between the inverter case 14, which is disposed closer to the output shaft 8, and the actuator 97, which is disposed closer to the input shaft 4, as viewed in the direction of the rotation axis X. It also becomes possible to dispose the actuator 97 within the height range of the inverter case 14.

[0111] Here, it is conceivable to provide the park gear 90 on the outer periphery of the motor shaft 20 (see FIG. 10 ) and the park mechanism 9 on the case member 11 side. However, in this case, the actuator 97 would be disposed on the outer periphery of the support wall portion 111 of the case member 11. Because the support wall portion 111 surrounds the stator 22 (see FIG. 2 ) of the motor 2, it is likely that the outer diameter of the support wall portion 111 will be larger than that of the peripheral wall portion 121 of the gear case 12. Therefore, the upper end 97t (see FIG. 12 ) of the actuator 97 disposed on the outer periphery of the support wall portion 111 is likely to be disposed at a higher position above the upper end 14t of the inverter case 14.

[0112] Therefore, in this embodiment, the park gear 90 is provided on the input shaft 4, and the actuator 97 is disposed in the gear case 12. Since the gear case 12 does not have a large-diameter part such as the stator 22, a recess such as the recess 125 can be formed in the peripheral wall portion 121, and the actuator 97 can be disposed therein. This makes it easier to dispose the actuator 97 at a lower position than when the park mechanism 9 is provided in the case member 11.

[0113] As described above, the drive device 1 for a vehicle of this embodiment has the following configuration: (1) The drive device 1 includes: the motor 2 which is a drive source for the vehicle V; the inverter INV which supplies current to the motor 2; the power transmission mechanism 3 which transmits the power of the motor 2 to the drive wheels WH, WH; the parking mechanism 9 which allows or restricts the transmission of power by the power transmission mechanism 3; and a housing HS which accommodates the motor 2, the inverter INV, the power transmission mechanism 3, and the parking mechanism 9. The housing HS has: a motor case 10 (motor accommodating portion) which accommodates the motor 2; an inverter case 14 (inverter accommodating portion) which accommodates the inverter INV and is attached to the upper part of the motor case 10 in the vertical direction based on the installation state of the drive device 1 on the vehicle V; and a gear case 12 (power transmission mechanism accommodating portion) which accommodates the power transmission mechanism 3 and is disposed adjacent to the motor case 10 in the direction of the rotation axis X (rotation axis X1 of the motor 2). The power transmission mechanism 3 has an input shaft 4 to which the power of the motor 2 is input, and an output shaft 8 that transmits the power of the motor 2 to the drive wheels WH, WH. The input shaft 4 and the output shaft 8 are arranged side by side in the fore-and-aft direction of the vehicle V when viewed from the direction of the rotation axis X. When viewed from the direction of the rotation axis X, the inverter case 14 is attached to an upper part of the motor case 10 on the side of the output shaft 8. When viewed from the direction of the rotation axis X, the actuator 97 of the parking mechanism 9 is arranged above the gear case 12 on the side of the input shaft 4.

[0114] When the inverter case 14 is disposed so as to extend from the output shaft 8 to the input shaft 4 as viewed from the direction of the rotation axis X, it may be necessary to dispose the actuator 97 so that it protrudes above the inverter case 14 to avoid interference with the inverter case 14. In such a case, the vertical height of the drive unit 1 is increased by the amount of protrusion of the actuator 97. This affects the mountability of the drive unit 1 to the vehicle V. Therefore, by disposing the inverter case 14 closer to the output shaft 8 in the fore-and-aft direction as viewed from the direction of the rotation axis X using the above configuration, space for disposing the actuator 97 on the input shaft 4 side can be secured. This eliminates the need to dispose the actuator 97 so that it protrudes above the inverter case 14, thereby reducing the possibility that the vertical height of the drive unit 1 will increase due to the provision of the actuator 97. This is expected to improve the mountability of the drive unit 1 to the vehicle V.

[0115] Furthermore, the motor case 10 and the gear case 12 are adjacent to each other in the direction of the rotation axis X. Therefore, by disposing the inverter case 14 on top of the motor case 10 and disposing the actuator 97 on top of the gear case 12, the inverter case 14 and the actuator 97 can be disposed with their positions offset in the direction of the rotation axis X. This reduces the possibility of interference between the inverter case 14, which is disposed closer to the output shaft 8, and the actuator 97, which is disposed closer to the input shaft 4, as viewed in the direction of the rotation axis X. It also becomes possible to dispose the actuator 97 within the height range of the inverter case 14.

[0116] (2) The power transmission mechanism 3 has an intermediate shaft 5 between the input shaft 4 and the output shaft 8. The rotation axis X2, which is the axis of the intermediate shaft 5, is located above the rotation axis X1, which is the axis of the input shaft 4, and the rotation axis X3, which is the axis of the output shaft 8. In the gear case 12, a recess 125 recessed downward toward the input shaft 4 is provided on the outer periphery of the region above the input shaft 4 when viewed from the direction of the rotation axis X. At least a portion of the actuator 97 is housed in the recess 125.

[0117] With this configuration, the rotation axis X2 of the intermediate shaft 5 is positioned above the rotation axis X1 of the input shaft 4, and thus a space is created above the input shaft 4 and to the side of the intermediate shaft 5, the size of which is determined according to the outer diameter of the gear of the intermediate shaft 5 (the radius r2 of the large-diameter gear portion 51). The outer periphery of the gear case 12 is recessed to form a recess 125 to fill this space, and at least a portion of the actuator 97 can be accommodated in the recess 125. This reduces the protrusion height of the actuator 97 from the outer periphery of the gear case 12, and the actuator 97 can be provided so that it does not protrude above the inverter case 14. This reduces the possibility that the vertical height of the drive unit 1 will increase due to the provision of the actuator 97, and is expected to improve the mountability of the drive unit 1 in the vehicle V.

[0118] (I) The large diameter gear portion 51 of the intermediate shaft 5 has a larger diameter than the gear portion 41 of the input shaft 4 that meshes with the large diameter gear portion 51.

[0119] With this configuration, a space is formed above the input shaft 4 and to the side of the intermediate shaft 5, making it easier to provide the recess 125 in the ceiling portion 121t of the gear case 12.

[0120] (3) The parking mechanism 9 includes a park gear 90 provided on the input shaft 4, a manual shaft 96 extending vertically on the side opposite the output shaft 8 as viewed from the input shaft 4 and connected to an actuator 97, and a park pole 91 that engages with and disengages from a tooth groove portion 902 (outer periphery) of the park gear 90 (switching between a state in which it is engaged with the tooth groove portion 902 and a state in which it is disengaged from the tooth groove portion 902) in conjunction with the rotation of the manual shaft 96 by the actuator 97. The park pole 91 is disposed below the input shaft 4.

[0121] With this configuration, a space is created below the input shaft 4 and to the side of the output shaft 8, the size of which is determined by the outer diameter of the gear of the output shaft 8 (the radius r3 of the final gear 61). By using this space to place the park pole 91, it is possible to reduce an increase in the vertical size of the drive unit 1, for example, by providing additional space for the park pole 91. Furthermore, since no other components of the park mechanism 9 are placed between the ceiling portion 121t of the gear case 12 and the park gear 90 in the vertical direction, it is easy to increase the depth of the recess 125. This is expected to improve the mountability of the drive unit 1 on the vehicle V.

[0122] (II) The radius r3 of the final gear 61 of the output shaft 8 is larger than the radius r9 of the park gear 90 of the input shaft 4 (r3>r9).

[0123] With this configuration, the park pole 91 can be placed in a space formed below the input shaft 4 and to the side of the final gear 61. This reduces the possibility that the vertical height of the drive unit 1 will increase due to the need to provide additional space for the park pole 91.

[0124] (III) When viewed from the top and bottom, the actuator 97, the input shaft 4, and the park pole 91 are arranged in an overlapping positional relationship.

[0125] With this configuration, the increase in size of the drive device 1 in the longitudinal direction of the vehicle can be suppressed.

[0126] (IV) When viewed from the front-rear direction, the park pole 91 and the input shaft 4 are positioned so as to overlap the final gear 61 of the output shaft 8 .

[0127] With this configuration, the park pole 91 and the input shaft 4 can be disposed within the range of the final gear 61 as viewed from the front-rear direction. Therefore, the increase in size of the drive unit 1 in the vertical direction is reduced compared to when, for example, the park pole 91 and the input shaft 4 are disposed offset downward from the final gear 61 as viewed from the front-rear direction.

[0128] (4) The motor case 10 has a case member 11 that surrounds the motor 2 and a cover member 13 that closes an opening in the case member 11 on the opposite side of the gear case 12 in the direction of the rotation axis X. The inverter case 14 is formed to have a range in the direction of the rotation axis X that straddles the outer periphery of the case member 11 and the outer periphery of the cover member 13.

[0129] With this configuration, the inverter case 14 can be disposed away from the gear case 12 in the direction of the rotation axis X. This makes it possible to avoid interference with the actuator 97 disposed above the gear case 12 without reducing the volume of the inverter case 14.

[0130] (5) The inverter case 14 has a connection portion 14c with the battery BT on the side surface facing the gear case 12. The ceiling portion 121t of the gear case 12 has a region on the output shaft 8 side as viewed from the direction of the rotation axis X that slopes downward from the intermediate shaft 5 toward the output shaft 8. The connection portion 14c opens to the outside of the region on the output shaft 8 side of the gear case 12 as viewed from the direction of the rotation axis X.

[0131] With this configuration, the cable Ca extending from the battery BT can be routed using the space above the output shaft 8 in the gear case 12. This also prevents interference between the cable Ca and the actuator 97. This allows for easy access to the connection portion 14c.

[0132] Although the embodiments of the present invention have been described above, the present invention is not limited to the aspects shown in these embodiments and can be modified as appropriate within the scope of the technical concept of the invention.

[0133] 1: Drive unit, 2: Motor, 3: Power transmission mechanism, 4: Input shaft, 5: Intermediate shaft, 6: Differential mechanism, 7, 7A, 7B: Drive shaft, 8: Output shaft, 9: Park mechanism, 10: Motor case (motor housing section), 11: Case member, 12: Gear case (power transmission mechanism housing section), 13: Cover member, 14: Inverter case (inverter housing section), 14c: Connection section, 15: Bulging wall section, 16: Support wall section, 17: Support wall section, 18: Lid section, 40: Shaft section, 41: Gear section, 50: Shaft section, 51: Large diameter gear section, 52: Small diameter gear section, 61: Final gear, 90: Park gear, 96: Manual shaft, 97: Actuator, 111: Support wall section, 121: Peripheral wall section, 121t: Ceiling section, 125: Recess, BT: Battery, Ca: Cable, HS: Housing, INV: Inverter, WH: Drive Wheel, X, X1, X2, X3: Rotating Shaft (Shaft Center)

Claims

1. A drive unit comprising: a motor that is a drive source for a vehicle; an inverter that supplies current to the motor; a power transmission mechanism that transmits the power of the motor to drive wheels; a parking mechanism that allows or restricts the transmission of the power by the power transmission mechanism; and a housing that accommodates the motor, the inverter, the power transmission mechanism, and the parking mechanism, wherein the housing has: a motor accommodating section that accommodates the motor; an inverter accommodating section that accommodates the inverter and is attached to an upper part of the motor accommodating section in a vertical direction based on the installation state of the drive unit on the vehicle; and a power transmission mechanism accommodating section that accommodates the power transmission mechanism and is arranged adjacent to the motor accommodating section in the direction of the rotation axis of the motor, and the power transmission mechanism has: an input shaft to which the power of the motor is input; and an output shaft that transmits the power of the motor to the drive wheels, and the input shaft and the output shaft are arranged side by side in the fore-and-aft direction of the vehicle when viewed in the direction of the rotation axis, a drive device in which, as viewed from the direction of the rotational axis, the inverter accommodating section is attached to an upper part of the output shaft side of the motor accommodating section, and an actuator of the park mechanism is disposed on an upper part of the input shaft side of the power transmission mechanism accommodating section, as viewed from the direction of the rotational axis.

2. A drive device according to claim 1, wherein the power transmission mechanism has an intermediate shaft between the input shaft and the output shaft, the axis of the intermediate shaft is located above the axis of the input shaft and the axis of the output shaft, the power transmission mechanism housing section has a recess recessed downward toward the input shaft on the outer periphery of the area on the input shaft side as viewed from the direction of the rotation axis, and at least a portion of the actuator is housed in the recess.

3. A drive device according to claim 2, wherein the parking mechanism comprises: a park gear provided on the input shaft; a manual shaft extending in the vertical direction on the side of the input shaft opposite the output shaft and connected to the actuator; and a park pole that engages with and disengages from the outer periphery of the park gear in conjunction with the rotation of the manual shaft by the actuator, the park pole being positioned below the input shaft.

4. A drive device according to claim 2, wherein the motor accommodating section has a cover that closes the opening of the motor accommodating section on the opposite side of the power transmission mechanism accommodating section in the direction of the rotation axis, and the inverter accommodating section is formed with a range in the direction of the rotation axis that straddles the outer periphery of the motor accommodating section and the outer periphery of the cover.

5. A drive device according to claim 4, wherein the inverter accommodating section has a connection section for connecting to a battery on the side facing the power transmission mechanism accommodating section, the region of the power transmission mechanism accommodating section on the output shaft side as viewed from the direction of the rotation axis is inclined downward from the intermediate shaft toward the output shaft, and the connection section opens to the outside of the region of the power transmission mechanism accommodating section on the output shaft side as viewed from the direction of the rotation axis.

Images