Drive device

Abstract

[Problem] To efficiently support a drive device.　[Solution] This drive device comprises: a motor that is a drive source of a vehicle; a power transmission mechanism that transmits power of the motor to a drive wheel; and a housing that houses the motor and the power transmission mechanism. The housing has a motor accommodation part and a power transmission mechanism accommodation part. The power transmission mechanism has an input shaft provided coaxially with the motor, and an output shaft disposed parallel to the input shaft so as to be spaced apart in the front-rear direction of the vehicle. The motor accommodation part has a first support part that rotatably supports the output shaft on one side in a rotation axis direction, a second support part that rotatably supports the output shaft on the other side, and a connection part that is disposed in an orientation along the output shaft on a side opposite to the input shaft in the front-rear direction when viewed from the output shaft, and that is placed in a range spanning the first support part and the second support part. The connection part is provided with a first attachment part for fixing the housing to the vehicle.

Description

Drive unit

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

[0002] Patent Document 1 discloses a drive device mounted on a vehicle.

[0003] Japanese Patent Application Laid-Open No. 2021-112052

[0004] Due to layout requirements, a drive unit mounted on a vehicle may be supported on the front and rear sides of the vehicle by the vehicle body. However, because other vehicle components are also located in front and behind the drive unit, the locations where the drive unit can be supported are often limited, making it difficult to support the drive unit efficiently.

[0005] Therefore, there is a need to efficiently support the drive unit.

[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; a power transmission mechanism that transmits power from the motor to drive wheels; and a housing that accommodates the motor and the power transmission mechanism, wherein the housing has: a motor accommodating section that accommodates the motor; 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 rotational axis of the motor, the power transmission mechanism having: an input shaft that is provided coaxially with the motor; and an output shaft that is arranged parallel to the input shaft and spaced apart in the fore-and-aft direction of the vehicle based on the installation state of the drive device on the vehicle, and the motor accommodating section has: a first support section that rotatably supports the output shaft on one side in the direction of the rotational axis; and a second support section that rotatably supports the output shaft on the other side in the direction of the rotational axis. a connecting portion that is arranged on the opposite side of the input shaft in the fore-and-aft direction from the output shaft, in a direction along the output shaft, and that is provided in a range spanning the first support portion and the second support portion, and a first mounting portion that fixes the housing to the body of the vehicle is provided on the connecting portion.

[0007] According to one aspect of the present invention, the drive device can be supported efficiently.

[0008] FIG. 1 is a schematic diagram illustrating the arrangement of a drive unit in a vehicle. FIG. 2 is a schematic diagram illustrating a general configuration of the drive unit. FIG. 3 is a diagram illustrating the drive unit. FIG. 4 is a diagram illustrating a bulging wall portion. FIG. 5 is a diagram illustrating a bulging wall portion. FIG. 6 is a diagram illustrating a bulging wall portion. FIG. 7 is a diagram illustrating a cover member. FIG. 8 is a diagram illustrating an inverter case. FIG. 9 is a diagram illustrating an inverter case. FIG. 10 is a diagram illustrating an inverter case. FIG. 11 is a diagram illustrating a second mounting portion.

[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 composed 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 forward direction of the vehicle, the backward direction of the vehicle), etc. For example, when 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. When 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 the present embodiment, a drive device 1 mounted on a vehicle V will be described as an example. Fig. 1 is a schematic diagram illustrating the arrangement of the drive device 1 in the vehicle V. Fig. 2 is a schematic diagram illustrating the general configuration of the drive device 1.

[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 FRa and FRb (vehicle bodies) that are spaced apart in the front-to-rear direction. The frames FRa and FRb 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 left and right drive wheels WH, WH, and an inverter INV that converts the power of a battery BT and supplies current to the motor 2. The drive unit 1 also includes a housing HS that accommodates the motor 2, the power transmission mechanism 3, and the inverter INV.

[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] 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] 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 have different diameters and are provided on the outer periphery of the shaft portion 50. 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.

[0024] The gear portion 41 of the input shaft 4 meshes with the large diameter gear portion 51 of the intermediate shaft 5. The small diameter gear portion 52 of the intermediate shaft 5 meshes with the final gear 61 of the differential mechanism 6.

[0025] 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) form 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] 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 B (see FIG. 11). The cover member 13 is connected to the other end 111b of the support wall portion 111 with a bolt B (see FIG. 11).

[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] A cylindrical wall portion 113 surrounding the rotation axis X1 is provided in a region of the wall portion 112 that intersects with the rotation axis X1. A bearing Bm is provided on the inner periphery of the cylindrical wall portion 113 on the motor chamber Sa side. 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 shaft portion 40 of the input shaft 4 is supported by the cylindrical wall portion 113 via the bearing B4.

[0032] 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.

[0033] 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.

[0034] The bulging wall 15 has a wall 152 extending forward from the other end 111b of the support wall 111. The wall 152 is oriented perpendicular to the rotation axis X3. The drive shaft 7A passes through the region of the wall 152 where the rotation axis X3 intersects with the wall 152 in the direction of the rotation axis X3. The wall 152 is provided with a cylindrical drive shaft support 152a that surrounds the drive shaft 7A.

[0035] A bearing B7 is supported on the inner periphery of the drive shaft support portion 152a. The drive shaft 7A is supported by the drive shaft support portion 152a via the bearing B7. The wall portion 152 constitutes a second support portion that rotatably supports the output shaft 8 on the other side in the direction of the rotation axis X.

[0036] The bulging wall portion 15 also has a wall portion 151. The wall portion 151 is located closer to one end 111a of the support wall portion 111 than the wall portion 152. The wall portion 151 extends forward (upward in the figure) from the support wall portion 111. The wall portion 151 is provided in a direction perpendicular to the rotation axis X3. A cylindrical differential case support portion 151a is provided in the wall portion 151 in a region where the rotation axis X3 intersects with the wall portion 151. The support cylinder 601 of the differential case 60 penetrates the differential case support portion 151a in the direction of the rotation axis X3.

[0037] A bearing B6 is supported on the inner periphery of the differential case support portion 151a. The support cylinder 601 of the differential case 60 is supported by the differential case support portion 151a via the bearing B6. The wall portion 151 constitutes a first support portion that rotatably supports the output shaft 8 on one side in the direction of the rotation axis X.

[0038] The bulging wall portion 15 has a connecting wall 153 (connecting portion) that connects the front ends of the wall portions 151, 152. The connecting wall 153 is provided in a direction along the rotation axis X3. A region of the connecting wall 153 on the one end 153a side (left side in the figure) of the wall portion 151 extends to the side of the differential case 60 and the final gear 61 toward the gear case 12.

[0039] One end 153a and the other end 153b of the connecting wall 153 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. The gear case 12 is connected to one end 153a of the connecting wall 153 with a bolt B (see FIG. 3).

[0040] The gear case 12 has a bottom wall portion 120 that is provided in a direction perpendicular to the rotation axes X1 to X3, and a peripheral wall portion 121 that completely surrounds the outer periphery of the bottom wall portion 120. At a tip end surface 121a of the peripheral wall portion 121, a rear region in the vehicle longitudinal direction (a lower region in FIG. 2) is joined to one end 111a of the support wall portion 111, and a front region (an upper region in FIG. 2) is joined to one end 153a of the connecting wall 153 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 the shaft portion 40 of the input shaft 4. As a result, both ends of the input shaft 4 in the direction of the rotation axis X1 are supported by the motor case 10 side and the gear case 12 side, and the input shaft 4 is provided rotatable about the rotation axis X1.

[0042] A bearing B5 is provided in a region of the bottom wall portion 120 where the rotation axis X2 intersects with the bearing B5. 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 motor case 10 side and the gear case 12 side, and the intermediate shaft 5 is provided rotatable about the rotation axis X2.

[0043] A cylindrical differential case support portion 122 is provided in the bottom wall portion 120 in an area where the rotation axis X3 intersects with the differential case 60. The support cylinder 602 of the differential case 60 penetrates the cylindrical differential case support portion 122 in the direction of the rotation axis X3. A bearing B6 is supported on the inner periphery of the differential case support portion 122. The support cylinder 602 of the differential case 60 is 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 side and the gear case 12 side, and the differential case 60 is 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 other end 111b side 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] FIG. 3 is a diagram illustrating the drive unit 1. FIG. 3 is a diagram illustrating the drive unit 1 as viewed from the front of the vehicle. Note that in FIG. 3, a portion of the connecting wall 153 is cut away to expose the walls 151, 152, and 154. FIG. 4 is a diagram illustrating the bulging wall portion 15. FIG. 4 is a diagram illustrating the drive unit 1 as viewed from the direction of the arrow A-A in FIG. 3. In FIG. 4, the area of ​​the wall portion 154 is cross-hatched to make the positional relationship easier to understand. FIG. 5 is a diagram illustrating the bulging wall portion 15. FIG. 5 is a schematic cross-sectional view of the drive unit 1 taken along line B-B in FIG. 3. FIG. 6 is a diagram illustrating the bulging wall portion 15. FIG. 6 is a schematic cross-sectional view of the drive unit 1 taken along line A-A in FIG. 5. FIG. 7 is a diagram illustrating the cover member 13. FIG. 7 is a diagram illustrating the drive unit 1 as viewed from the direction of the arrow A-A in FIG. 6. FIG. 8 is a diagram illustrating the inverter case 14. FIG. 8 is a view of the drive unit 1 as seen from the direction of the arrows CC in FIG. 3. Note that in FIG. 8, 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 shown with hatching of different pitches. FIG. 9 is a diagram illustrating the inverter case 14. FIG. 9 is a schematic cross-sectional view of the drive unit 1 taken along line A-A in FIG. 8. FIG. 10 is a diagram illustrating the inverter case 14. FIG. 10 is a schematic cross-sectional view of the drive unit 1 taken along line B-B in FIG. 8. FIG. 11 is a diagram illustrating the second mounting portion. FIG. 11 is a view of the drive unit 1 as seen from the rear of the vehicle.

[0049] As shown in FIG. 3 , the connecting wall 153 of the bulging wall portion 15 is provided in a range that vertically crosses the drive shaft 7A when viewed from the front-rear direction. As shown in FIG. 6 , the connecting wall 153 is provided in a range in the direction of the rotation axis X that extends from the differential case 60 across the wall portion 151 to the wall portion 152. When viewed from the front-rear direction, the connecting wall 153 overlaps with the differential case 60 and the walls 151 and 152. As described above, the walls 151 and 152 rotatably support the output shaft 8 (drive shaft 7A). Therefore, the rigidity of the walls 151 and 152 against the load acting from the output shaft 8 in the direction of the rotation axis X is improved.

[0050] As shown in Figure 5, the connecting wall 153 of the bulging wall portion 15 is located on the front side of the vehicle when viewed from the support wall portion 111. The connecting wall 153 is provided with a gap between it and the support wall portion 111 in the front-to-rear direction. A wall portion 154 is provided above the area where the connecting wall 153 and the support wall portion 111 are located. The wall portion 154 is provided so as to straddle the connecting wall 153 and the support wall portion 111. A space Sd is formed below the wall portion 154 and is surrounded by the wall portion 154, the connecting wall 153, and the support wall portion 111. This space Sd opens to the lower part of the housing HS.

[0051] The drive shaft 7A is disposed in the space Sd when viewed from the direction of the rotation axis X. The wall 154 separates the space Sd in which the drive shaft 7A is disposed from an internal space Sc of the inverter case 14, which will be described later. In other words, the wall 154 forms the bottom wall of the inverter case 14.

[0052] 6, the wall portion 154 has a length in the direction of the rotation axis X (left-right direction in the figure) that matches the length of the connecting wall 153. One end 154a and the other end 154b of the wall portion 154 in the direction of the rotation axis X are provided flush with one end 153a and the other end 153b of the connecting wall 153, respectively.

[0053] Walls 151 and 152 are connected between one end 154a and the other end 154b of wall 154 in the direction of rotation axis X. Walls 151 and 152 are connected at their front ends (the far side of the page in FIG. 6 ) to connecting wall 153 and at their upper ends (the upper side in FIG. 6 ) to wall 154. In other words, connecting wall 153 connects walls 151 and 152 to wall 154 (inverter case 14). This improves the rigidity of wall 151 and 152 against a load acting from output shaft 8 in the direction of rotation axis X and against loads in the vertical direction.

[0054] Furthermore, as shown in FIG. 5 , when viewed from the direction of the rotation axis X, the wall portion 152 connects the connecting wall 153, the wall portion 154, and the support wall portion 111. Although not shown, the wall portion 151 (see FIG. 6 ) also connects the connecting wall 153, the wall portion 154, and the support wall portion 111, similarly to the wall portion 152. As shown in FIG. 4 , when the case member 11 is viewed from below in the vertical direction, the wall portion 154 is provided across the four walls (wall portions 151, 152, connecting wall 153, and support wall portion 111). This improves the rigidity of the wall portions 151, 152 against a load acting from the output shaft 8 (drive shaft 7A) in the direction of the rotation axis X, against a load in the vertical direction, and against a load in the front-rear direction.

[0055] 5, an inverter case 14 that houses the inverter INV is provided above the wall portion 154 of the bulging wall portion 15. When viewed from above, the inverter case 14 has a rear end portion in the front-to-rear direction that overlaps with the support wall portion 111.

[0056] 3 , the inverter case 14 is provided in a range in the direction of the rotation axis X that straddles the case member 11 and the cover member 13. The inverter case 14 is offset with respect to the gear case 12, and is provided at a position spaced apart from the gear case 12. The inverter case 14 has support walls 16 and 17 provided on the case member 11 and the cover member 13, and a lid 18 provided across these support walls 16 and 17.

[0057] As shown in Fig. 5, the support wall portion 16 protrudes upward from the wall portion 154 of the bulging wall portion 15 and the support wall portion 111. As shown in Fig. 8, when viewed from above in the vertical direction, the support wall portion 16 is a continuous wall made up of a first wall portion 161, a second wall portion 162, and a third wall portion 163.

[0058] In the case member 11, the first wall portion 161 is provided at a position offset from the joint surface with the cover member 13 toward the gear case 12 (right side in the figure) and oriented along the front-to-rear direction of the vehicle (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 (left side in the figure). When viewed from above, the third wall portion 163 extends from the rear end of the first wall portion 161 toward the cover member 13 (left side in the figure). The second wall portion 162 and the third wall portion 163 are provided oriented along the direction of the rotation axis X.

[0059] 5, the second wall portion 162 is located on the front side of the vehicle when viewed from the direction of the rotation axis X. The second wall portion 162 protrudes upward from the front end of the wall portion 154. The second wall portion 162 is provided on a line Lm that is common to the connecting wall 153. The line Lm is a line that extends in the vertical direction.

[0060] The third wall portion 163 is located on the rear side of the vehicle when viewed from the direction of the rotation axis X. The third wall portion 163 is in the area of ​​the support wall portion 111 and protrudes upward from a position offset forward from the vertical line VL1. The vertical line VL1 is a vertical line passing through the rotation axis X1 of the motor 2.

[0061] 9, in the region of the support wall portion 111, the tip surface 163a of the third wall portion 163 in the direction of the rotation axis X is provided flush with the other end 111b of the support wall portion 111. As shown in Fig. 10, in the region of the bulging wall portion 15, the tip surface 163a of the third wall portion 163 in the direction of the rotation axis X is provided flush with the other end 154b of the wall portion 154.

[0062] 8 , a tip surface 162a of the second wall portion 162 in the direction of the rotation axis X is provided flush with a tip surface 163a of the third wall portion 163. 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. 9 ), and the other end 154b of the wall portion 154 of the bulging wall portion 15 (see FIG. 10 ) are located on the same plane along the mating surfaces of the case member 11 and the cover member 13.

[0063] 4 and 7, the support wall 17 of the cover member 13 bulges forward from the peripheral wall 131. Specifically, as shown in Fig. 7, the support wall 17 is located 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 17 overlaps with the support wall 16 of the case member 11 and is offset from the drive shaft 7A.

[0064] 8, 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.

[0065] When viewed from above in the vertical direction, the support wall portion 17 is a continuous wall made up of a first wall portion 171, a second wall portion 172, and a third wall portion 173. In the cover member 13, the first wall portion 171 extends in the front-rear direction along the side edge of the extending wall portion 132 at a position offset away from the case member 11 (to the left in the figure). The rear end of the first wall portion 171 reaches between the rotation axis X1 and the rotation axis X2.

[0066] The second wall portion 172 extends from the front end of the first wall portion 171 toward the case member 11. The third wall portion 173 extends from the rear end of the first wall portion 171 toward the case member 11. The second wall portion 172 and the third wall portion 173 are provided oriented along the direction of the rotation axis X.

[0067] 9, a tip surface 173a of the third wall portion 173 on the case member 11 side (right side in the figure) is provided flush with one end 131a of the peripheral wall portion 131. As shown in Fig. 10, the tip surface 173a of the third wall portion 173 in the direction of the rotation axis X is also provided flush with one end 132a of the extending wall portion 132.

[0068] 8, a tip surface 172a of the second wall portion 172 on the case member 11 side (right side in the figure) is provided flush with a tip surface 173a of the third wall portion 173. 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 FIG. 9), and one end 132a of the extending wall portion 132 (see FIG. 10) are located on the same plane along the mating surfaces of the case member 11 and the cover member 13.

[0069] As shown in Fig. 8, 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. 9, 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. 10, the other end 154b of the wall portion 154 of the bulging wall portion 15 abuts against one end 132a of the extending wall portion 132.

[0070] As a result, in the motor case 10, a space is formed that is surrounded by the support wall 16 of the case member 11, the support wall 17 of the cover member 13, the wall 154 of the case member 11, the extending wall 132 of the cover member 13, the support wall 111 of the case member 11, and the peripheral wall 131 of the cover member 13 (see FIGS. 9 and 10 ). This space constitutes the internal space Sc of the inverter case 14.

[0071] 9 and 10 , the upper end surface 16a of the support wall portion 16 and the upper end surface 17a of the support wall portion 17 are flush with each other. The joining surface 18a of the lid portion 18 is joined to the upper end surfaces 16a, 17a of the support walls 16, 17 without any gaps. Therefore, the opening of the internal space Sc surrounded by the support walls 16, 17 is closed by the lid portion 18. As a result, the inverter INV (see FIG. 8 ) is accommodated in the internal space Sc of the inverter case 14.

[0072] 1, the drive unit 1 according to this embodiment is arranged between frames FRa and FRb spaced apart in the longitudinal direction of the vehicle V. The frame FRa is provided in front of the drive unit 1 and oriented in the vehicle width direction. The frame FRb is provided in the rear of the drive unit 1 and oriented in the vehicle width direction.

[0073] 5, the housing HS of the drive unit 1 is attached to the front and rear frames FRa and FRb via brackets BK with bolts B. For this reason, the drive unit 1 is provided with bosses 155 (first attachment portions) and bosses 115 (second attachment portions) on the front and rear sides of the housing HS, respectively, for fixing the brackets BK.

[0074] 5, the boss portion 155 is provided on the connecting wall 153 of the bulging wall portion 15. The boss portion 155 is provided below the drive shaft 7A.

[0075] As shown in Fig. 3, one boss portion 155 is provided on one end 153a side and one boss portion 155 is provided on the other end 153b side of the connecting wall 153 in the direction of the rotation axis X. The boss portion 155 on the one end 153a side and the boss portion 155 on the other end 153b side are connected by a rib 156. The rib 156 is linear and extends along the rotation axis X. As shown in Fig. 4, the boss portions 155, 155 are located on one side and the other side of the motor 2.

[0076] As shown in FIG. 5 , the boss portion 115 is provided on the support wall portion 111. The boss portion 115 is provided on the opposite side of the connecting wall 153 in the front-rear direction, with the rotation axis X (rotation axis X1 of the motor 2) sandwiched between them. As shown in FIG. 11 , one boss portion 115 is provided on one end 111 a side and one on the other end 111 b side of the support wall portion 111 in the direction of the rotation axis X. The boss portion 115 on the one end 111 a side and the boss portion 115 on the other end 111 b side are connected by a rib 116. The rib 116 is linear and oriented along the rotation axis X. The boss portions 115, 115 are provided on one side and the other side of the motor 2.

[0077] 5, the boss portion 155 provided on the connecting wall 153 and the boss portion 115 provided on the support wall portion 111 are integrally formed on the common case member 11. The boss portion 155 and the boss portion 115 are aligned vertically. Specifically, the boss portion 155 and the boss portion 115 are located on a horizontal line HLa that is perpendicular to the vertical line VL1.

[0078] 2, in the drive unit 1 according to this embodiment, the output shaft 8 is disposed in parallel to the input shaft 4 and the motor shaft 20 at a distance in the front-rear direction. As shown in FIG. 5, a drive shaft 7A is provided between the frame FRa and the motor 2 in the front-rear direction.

[0079] Therefore, for example, in the case of a housing HS that does not have the connecting wall 153 according to the embodiment, when fixing the housing HS to the front frame FRa, a mounting portion (boss portion) for the front frame FRa is provided on the gear case 12, the inverter case 14, or the like to avoid interference with the drive shafts 7A and 7B, which are the output shaft 8. In this case, depending on the layout of the vehicle body, measures such as increasing the size of the brackets BK or increasing the number of brackets BK may be required to fix the housing HS. For example, if it is not possible to provide the brackets BK in a position on the vehicle body adjacent to the gear case 12 or the inverter case 14, the brackets BK will be positioned around the gear case 12 or the inverter case 14. In this case, the distance to the mounting portion (boss portion) of the drive unit 1 increases by the amount of the positional shift. As a result, it may be necessary to take measures such as increasing the size of the brackets BK or increasing the number of brackets BK when attaching the drive unit 1 (housing HS) to the vehicle body.

[0080] However, if the bracket BK is enlarged, additional space is required around the housing HS to accommodate the enlarged bracket BK. Furthermore, if the number of brackets BK is increased, mounting portions for the brackets BK, such as boss portions, must be provided on the gear case 12 and the inverter case 14. In particular, adding brackets BK reduces the efficiency of the work of mounting the drive unit 1 (housing HS) to the vehicle body.

[0081] Therefore, in the housing HS according to this embodiment, a connecting wall 153 is provided in front of the drive shaft 7A, and a boss 155 is provided on the connecting wall 153 as a mounting portion for the bracket BK (see FIG. 5 ). In this embodiment, the connecting wall 153 is oriented along the drive shaft 7A and is provided in a range spanning the wall portions 151 and 152, which are spaced apart in the direction of the rotation axis X3 of the drive shaft 7A (the left-right direction in FIG. 6 ). Therefore, providing the boss 155 on the connecting wall 153 increases the flexibility in the boss placement. This allows the drive unit 1 (housing HS) to be fixed to the vehicle body while minimizing the need for measures such as increasing the size or number of brackets BK. This allows the drive unit 1 having the housing HS to be efficiently mounted.

[0082] Furthermore, bosses 155, 115 are provided at the front and rear ends of the housing HS (see FIGS. 4 and 5), which allows the drive unit 1 to be supported more stably on the vehicle body side.

[0083] 4, when viewed from the front-to-rear direction, boss portion 155 and boss portion 115 are provided on one side (left side in FIG. 4) and the other side (right side in FIG. 4) of motor 2. This allows housing HS to be supported with motor 2, which is a heavy object, sandwiched therebetween, improving the support stability of drive unit 1.

[0084] 5, the boss portion 155 and the boss portion 115 are aligned in the vertical direction when viewed from the direction of the rotation axis X. This allows the load in the pitch direction acting on the drive unit 1 to be reduced compared to, for example, a case in which the boss portion 155 and the boss portion 115 are aligned in the vertical direction.

[0085] The boss portions 155 and 115 are formed integrally with the case member 11 that constitutes the motor case 10. For example, if the boss portions 155 and 115 were provided on different cases (the case member 11 and the cover member 13) and fixed to the frames FRa and FRb, stress would likely concentrate at the joint between the case member 11 and the cover member 13 due to external forces acting on the housing HS from the frames FRa and FRb. Therefore, by forming the boss portions 155 and 115 integrally with the case member 11, stress is less likely to concentrate even if external forces act from the frames FRa and FRb.

[0086] As described above, the vehicle drive unit 1 of this embodiment has the following configuration: (1) The drive unit 1 includes: a motor 2 that is a drive source for the vehicle V; a power transmission mechanism 3 that transmits power from the motor 2 to the drive wheels WH; and a housing HS that accommodates the motor 2 and the power transmission mechanism 3. The housing HS includes: a motor case 10 (motor housing) that accommodates the motor 2; and a gear case 12 (power transmission mechanism housing) that 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 includes: an input shaft 4 that is provided coaxially with the motor 2; and an output shaft 8 that is disposed parallel to the input shaft 4 and spaced apart in the fore-and-aft direction of the vehicle V, based on the installation state of the drive unit 1 on the vehicle V. The case member 11 of the motor case 10 has: a wall portion 151 (first support portion) on one side in the direction of the rotation axis X that rotatably supports the differential case 60 of the output shaft 8; a wall portion 152 (second support portion) on the other side in the direction of the rotation axis X that rotatably supports the drive shaft 7A of the output shaft 8; and a connecting wall 153 (connecting portion) that is disposed on the opposite side of the input shaft 4 in the front-to-rear direction as viewed from the output shaft 8, oriented along the drive shaft 7A, and provided in a range spanning the wall portions 151 and 152. The connecting wall 153 is provided with a boss portion 155 (first mounting portion) that fixes the housing HS to the frame FRa (vehicle body) of the vehicle V.

[0087] According to the embodiment, in the drive unit 1 in which the motor 2 and the output shaft 8 are arranged parallel to each other with a gap in the longitudinal direction of the vehicle, the drive shaft 7A of the output shaft 8 is provided between the frame FRa and the motor 2 in the longitudinal direction. Therefore, for example, when fixing a housing HS without a connecting wall 153 to the front frame FRa, it is possible to fix the housing HS to the front frame FRa at a position that avoids the drive shaft 7A of the gear case 12 (see FIG. 3 ), the inverter case 14, etc. In this case, depending on the layout of the vehicle body, it may be necessary to enlarge the bracket BK or increase the number of brackets BK. For example, if the bracket BK cannot be provided in a position on the vehicle body adjacent to the gear case 12 or the inverter case 14, the bracket BK will be provided at a position shifted to the periphery. Since the shifted position increases the distance to the boss portion 155 of the drive unit 1, it may be necessary to enlarge the bracket BK or increase the number of brackets BK to attach the drive unit 1 to the vehicle body. However, if the bracket BK is made larger, additional space is required. Furthermore, if the number of brackets BK is increased, it is necessary to provide bosses corresponding to each bracket BK on the gear case 12 and the inverter case 14. These factors reduce the mounting efficiency of the housing HS. Therefore, with the above-described configuration, a connecting wall 153 is provided on the front side of the drive shaft 7A, and bosses 155 serving as mounting portions for the brackets BK are provided on the connecting wall 153. This allows the bosses 155 to be provided on the connecting wall 153, which is oriented along the drive shaft 7A and is provided in a range spanning the wall portions 151 and 152, thereby increasing the flexibility in the placement of the bosses 155. Therefore, the drive unit 1 can be fixed to the vehicle body without increasing the size of the brackets BK or the number of brackets BK. Therefore, the drive unit 1 can be mounted efficiently. Furthermore, by providing the connecting wall 153 across the walls 151 and 152 that support the output shaft 8, the rigidity of the walls 151 and 152 against a load acting from the output shaft 8 in the direction of the rotation axis X can be improved.

[0088] (2) The housing HS includes an inverter INV that supplies current to the motor 2. The housing HS accommodates the inverter INV and also includes an inverter case 14 (inverter accommodating portion) that is disposed above the drive shaft 7A of the output shaft 8 in the vertical direction based on the installation state of the drive unit 1 on the vehicle V. The connecting wall 153 is provided across a wall portion 154, which is the bottom wall of the inverter case 14, the wall portion 151, and the wall portion 152.

[0089] According to the embodiment, the wall portions 151 and 152 that support the output shaft 8 are supported by the connecting wall 153 and the wall portion 154. When the vehicle is traveling, a load in the direction of the rotation axis X and a load in the vertical direction act on the walls 151 and 152 from the output shaft 8. With the above configuration, the connecting wall 153 is fixed at three locations, namely to the wall portion 154 of the inverter case 14, the wall portion 151, and the wall portion 152, thereby improving the rigidity of the walls 151 and 152 against the load in the direction of the rotation axis X and the load in the vertical direction.

[0090] (3) The case member 11 constituting the motor case 10 has a support wall portion 111 that supports the motor 2. When viewed from above, the inverter case 14 has a portion that overlaps with the support wall portion 111. The wall portion 151 and the wall portion 152 are provided across the connecting wall 153, the wall portion 154 that is the bottom wall of the inverter case 14, and the support wall portion 111.

[0091] 5 and 6 , the walls 151 and 152 are further fixed to three locations: the inverter case 14 (wall 154), the connecting wall 153, and the support wall 111. This improves the rigidity of the walls 151 and 152 against a load acting from the output shaft 8 in the direction of the rotation axis X, a load in the up-down direction, and a load in the front-rear direction.

[0092] (4) The motor case 10 has a boss portion 115 (second mounting portion) on the side opposite the connecting wall 153, which sandwiches the rotation axis X1 of the motor 2 in the fore-and-aft direction. The boss portion 115 secures the housing HS to the frame FRb (vehicle body) of the vehicle V.

[0093] According to the embodiment, the front and rear sides of the housing HS can be fixed to the frames FRa and FRb of the vehicle V, so that the drive unit 1 can be supported more stably on the vehicle body side.

[0094] (I) The boss portion 155 and the boss portion 115 are provided on one side and the other side of the motor 2 when viewed from the front-rear direction.

[0095] With this configuration, the housing can be supported at a position sandwiching the motor 2, which is a heavy object, and therefore the support stability of the drive device 1 is improved.

[0096] (II) When viewed from the direction of the rotation axis X, the boss portion 155 and the boss portion 115 are aligned in the vertical direction.

[0097] With this configuration, the load acting on the drive device 1 in the pitch direction can be reduced compared to when the boss portion 155 and the boss portion 115 are provided at different positions in the vertical direction, for example.

[0098] (III) The boss portion 155 and the boss portion 115 are integrally formed with the case member 11 that constitutes the motor case 10 .

[0099] For example, if boss portion 155 and boss portion 115 are provided on different cases (case member 11 and cover member 13) and fixed to frames FRa, FRb, an external force acting on housing HS from the frames FRa, FRb side is likely to cause stress to concentrate at the joint between case member 11 and cover member 13. Therefore, by configuring as described above, stress is less likely to concentrate even if an external force acts from frames FRa, FRb.

[0100] In the embodiment, the output shaft 8 is disposed on the front side of the motor 2 in the front-rear direction, but this is not limiting. For example, the output shaft 8 may be disposed on the rear side of the motor 2. In this case, the connecting wall 153 and the boss portion 155 are located at the rear end of the housing HS, and the boss portion 115 is located at the front end of the housing HS. This also allows the drive unit 1 to be mounted efficiently.

[0101] 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.

[0102] 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, 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), 15: bulging wall section, 111: support wall section, 115: boss section (second mounting section), 151: wall section (first supporting section), 152: wall section (second supporting section), 153: connecting wall (connecting section), 154: wall section, 155: boss section (first mounting section), FRa, FRb: frame (vehicle body), HS: housing, INV: inverter, V: vehicle, WH: drive wheel, X, X1, X2, X3: rotating shaft

Claims

1. A drive unit comprising: a motor that is a drive source for a vehicle; a power transmission mechanism that transmits power from the motor to drive wheels; and a housing that accommodates the motor and the power transmission mechanism, wherein the housing has: a motor accommodation section that accommodates the motor; and a power transmission mechanism accommodation section that accommodates the power transmission mechanism and is arranged adjacent to the motor accommodation section in the direction of the motor's rotational axis, the power transmission mechanism has: an input shaft that is arranged coaxially with the motor; and an output shaft that is arranged parallel to the input shaft and spaced apart in the fore-and-aft direction of the vehicle based on the installation state of the drive unit on the vehicle, the motor accommodation section has: a first support section that rotatably supports the output shaft on one side in the direction of the rotational axis; a second support section that rotatably supports the output shaft on the other side in the direction of the rotational axis; and a connecting section that is arranged along the output shaft on the opposite side of the input shaft in the fore-and-aft direction as viewed from the output shaft, and is provided in a range spanning the first support section and the second support section, The coupling portion is provided with a first mounting portion that fixes the housing to a body of the vehicle.

2. A drive device according to claim 1, wherein the housing has an inverter accommodating section arranged above the output shaft in the vertical direction based on the installation state of the drive device on the vehicle, and the connecting section is provided across the inverter accommodating section, the first support section, and the second support section.

3. A drive device according to claim 2, wherein the motor accommodating section has a support wall section that supports the outer periphery of the motor, and when viewed from above, the inverter accommodating section has a portion that overlaps with the support wall section, and the first support section and the second support section are provided across the connecting section, the inverter accommodating section, and the support wall section.

4. A drive device according to claim 1, wherein the motor accommodating section has a second mounting section for fixing the housing to the vehicle body on the side opposite the connecting section across the rotation shaft of the motor in the longitudinal direction.

Images