JP2021131097A - Vehicle drive unit - Google Patents

Abstract

To reduce noise generated at a gear row while suppressing the size enlargement and a cost increase of a vehicle drive unit including a rotating electric machine and the gear row.SOLUTION: A stator of a rotating electric machine is fastened to a bulkhead for partitioning the inside of a case into a first chamber in which the rotating electric machine is arranged, and a second chamber in which a gear row is arranged with a plurality of bolts, and the bulkhead includes a plurality of bolt holes into which the bolts are screwed, and holds a plurality of bearings for rotatably supporting a corresponding one shaft out of a plurality of shafts in the second chamber. At least any one of the plurality of bolt holes is included in a range which is surrounded by two pieces of common outer tangents of an external periphery of a first bearing for supporting a first shaft out of the plurality of shafts when viewed from an axial direction of the rotating electric machine, and an external periphery of a second bearing for supporting a second shaft which is different from the first shaft, a line component for connecting contact points of the external periphery of the first bearing and the two pieces of common outer tangents, and a line component for connecting contact points of the external periphery of the second bearing and the two pieces of common outer tangents.SELECTED DRAWING: Figure 2

Description

The present disclosure relates to a vehicle drive device including a rotary electric machine and a gear train connected to the rotary electric machine.

Conventionally, as a drive device for a vehicle of this type, an electric motor, a power transmission mechanism for transmitting power between the electric motor and a pair of left and right drive shafts (drive wheels), an electric motor, and a power transmission mechanism are accommodated. Those including cases are known (see, for example, Patent Document 1). In this vehicle drive device, the rotor of the electric motor is fixed to a cylindrical rotor shaft, and the rotor shaft is rotatably supported around a rotation axis by a case via a pair of first bearings. Further, the power transmission mechanism includes a gear mechanism (gear train) connected to the electric motor, the gear mechanism, and a differential gear connected to the pair of drive shafts. The gear mechanism consists of a cylindrical first rotating shaft connected to the rotor shaft of the electric motor, a pinion gear integrally formed with the first rotating shaft, a small-diameter gear that meshes with the differential gear of the differential gear, and a small-diameter gear. It includes a large-diameter gear having a larger diameter and meshing with a pinion gear of the first rotating shaft, and a cylindrical second rotating shaft in which a small-diameter gear and a large-diameter gear are integrally fixed. The first rotating shaft is rotatably supported coaxially with the rotor shaft by the case via a pair of third bearings, and the second rotating shaft extends parallel to the rotating axis of the rotor shaft by the case via the second bearing. It is rotatably supported around the axis of rotation. The differential gear includes a pair of pinion gears, a pair of side gears that are fixed to the drive shaft and mesh with the pair of pinion gears, a pinion shaft that supports the pair of pinion gears, and a differential case that houses the pair of pinion gears and the pair of side gears. , The above-mentioned differential ring gear fixed to the outer peripheral portion of the differential case.

JP-A-2019-129608

In the vehicle drive device as described above, the noise (gear noise) generated in the gear train tends to increase as the eccentricity of the shaft to which the gear is fixed increases. In order to reduce such gear noise, it is effective to increase the support rigidity of the shaft. Then, for example, the support rigidity of the shaft is increased by increasing the wall thickness of the shaft support portion (boss portion that holds the bearing) of the case or forming ribs on the case so as to be located around the bearing. be able to. However, if the wall thickness is increased in a part of the case or ribs are formed in the case, the size of the entire device (weight increase) and cost increase are caused.

Therefore, the main object of the present disclosure is to reduce the noise generated in the gear train while suppressing the increase in size and cost of the vehicle drive device including the rotary electric machine and the gear train.

The vehicle drive device of the present disclosure includes a rotary electric machine including a stator and a rotor, a plurality of shafts including at least an input shaft coaxially connected to the rotor and an output shaft connected to a drive wheel, and the input shaft and the above. In a vehicle drive device including a gear train that transmits power to and from an output shaft, the rotary electric machine, and a case that accommodates the gear train, the rotary electric machine is arranged inside the case by a partition wall. It is divided into a first chamber and a second chamber in which the gear train is arranged, and the stator of the rotary electric machine is formed in the partition wall so as to open in the first chamber via a plurality of fastening portions. A first bearing that is fastened to the partition and supports the first shaft of the plurality of shafts on the second chamber side is different from the first shaft of the plurality of shafts. Holds the second bearing that supports the two shafts, and at least one of the plurality of fastening portions is the outer circumference of the first bearing and the outer circumference of the second bearing when viewed from the axial direction of the rotary electric machine. The line segment connecting the contacts of the outer circumference of the first bearing and the two common tangent wires, and the contacts of the outer circumference of the second bearing and the two common tangent wires. It is included in the range surrounded by the line connecting the bearings.

In the vehicle drive device of the present disclosure, the case includes a partition wall that divides the inside into a first chamber in which a rotary electric machine is arranged and a second chamber in which a gear train is arranged. Further, the partition wall of the case includes a plurality of fastening portions each opened in the first chamber, and the stator of the rotary electric machine is fastened to the partition wall via the plurality of fastening portions. Further, the partition wall includes a first bearing that supports the first shaft of the plurality of shafts and a second bearing that supports a second shaft that is different from the first shaft of the plurality of shafts on the second chamber side. To hold. Then, at least one of the plurality of fastening portions is two common external line segments, one on the outer circumference of the first bearing and the other on the outer circumference of the second bearing, and two on the outer circumference of the first bearing when viewed from the axial direction of the rotary electric machine. It is included in the range surrounded by the line segment connecting the contacts with the common tangent line of the above and the line segment connecting the contact points between the outer circumference of the second bearing and the two common tangent lines. As a result, the rigidity of the partition wall fastened to the partition wall (annular rigidity) is used to increase the rigidity of the partition wall around the first and second bearings, so that the partition wall is deformed around the first and second bearings. It becomes possible to suppress it satisfactorily. Therefore, in the vehicle drive device of the present disclosure, the support rigidity of the first shaft by the first bearing is not increased or ribs are formed on the partition wall around the first and second bearings. And the support rigidity of the second shaft by the second bearing can be increased. As a result, it is possible to suppress the eccentricity of the first and second shafts and reduce the noise generated in the gear train while suppressing the increase in size and cost of the vehicle drive device including the rotary electric machine and the gear train. It becomes.

It is sectional drawing which shows the drive device for a vehicle of this disclosure. It is a front view of the drive device for a vehicle of this disclosure seen from the axial direction of a rotary electric machine.

Next, a mode for carrying out the invention of the present disclosure will be described with reference to the drawings.

FIG. 1 is a cross-sectional view showing the vehicle drive device 1 of the present disclosure. The vehicle drive device 1 shown in the figure is mounted on an electric vehicle (not shown) and powers a pair of drive shafts (output shafts) DS connected to a pair of left and right drive wheels (not shown, for example, front wheels) of the electric vehicle. It is the one to output. The vehicle drive device 1 is powered (torque) between the case 2, the motor generator (rotary electric machine) 3 housed in the case 2, and the motor generator 3 and the pair of drive shafts DS housed in the case 2. ) Is included in the gear train 4.

The case 2 is fastened (coupled) to the first case 21, the second case 22 which is fastened (coupled) to the first case 21 via the plurality of bolts 25, and the second case 22 via the plurality of bolts 26. The third case 23 is included, and the cover 24 is fastened (coupled) to the first case 21 via a plurality of bolts 27. In the present embodiment, the first to third cases 21, 22, 23 and the cover 24 are all cast products made of aluminum alloy.

The first case 21 is formed in a substantially tubular shape, and the opening on one end side (right end side in FIG. 1) of the first case 21 is closed by the cover 24. The second case 22 defines a motor chamber (first chamber) M in which the motor generator 3 is arranged together with the first case 21 and the cover 24, and the partition wall 220 formed so as to face the cover 24. include. The third case 23 defines a gear chamber (second chamber) G in which the gear row 4 is arranged together with the second case 22, and the gear chamber G is a motor by the partition wall 220 of the second case 22 as shown in the figure. It is separated from the room M. That is, the inside of the case 2 is divided into a motor chamber M and a gear chamber G by a partition wall 220.

The motor generator 3 is a synchronous generator motor (three-phase AC motor) including a stator 30 and a rotor 35, and exchanges electric power with a power storage device (battery, not shown) via an inverter (not shown). The motor generator 3 operates as an electric motor that is driven by electric power from the power storage device to generate drive torque, and outputs regenerative braking torque when braking an electric vehicle.

The stator 30 includes an annular stator core 31 and a stator coil 32 wound around the stator core 31. The stator core 31 is integrally formed by, for example, laminating a plurality of electromagnetic steel sheets formed in an annular shape by press working and connecting them in the stacking direction. The stator coil 32 includes three coils of U-phase, V-phase, and W-phase, and is electrically connected to the inverter via a bus bar (not shown) of V-phase, U-phase, or W-phase.

In the present embodiment, the stator core 31 has a plurality of (for example, three in the present embodiment) overhangs protruding outward in the radial direction from the outer peripheral surface, and each of the overhangs has a through hole extending in the axial direction. Is formed. Further, a plurality of (for example, three in this embodiment) boss portions 225 are formed on the partition wall 220 of the second case 22 at intervals in the circumferential direction so as to project toward the motor chamber M side (cover 24 side). Has been done. Further, each boss portion 225 is formed with a bolt hole (screw hole) H as a fastening portion so as to open on the motor chamber M side. Then, bolts 33 are inserted into the through holes of the stator core 31, and each bolt 33 is screwed into the bolt hole H of the corresponding boss portion 225. As a result, the stator 30 is fastened (fixed) to the partition wall 220, that is, the case 2 so as to be located in the motor chamber M.

The rotor 35 includes an annular rotor core 36, end plates arranged on both sides of the rotor core 36 in the axial direction, and the like. The rotor core 36 is formed by, for example, laminating a plurality of electromagnetic steel sheets formed in an annular shape by press working. Further, the rotor core 36 is formed with a plurality of through holes (not shown) extending in the axial direction at intervals in the circumferential direction, and a permanent magnet is embedded in each through hole. In the present embodiment, the rotor core 36 is fixed to the cylindrical rotor shaft RS by, for example, a shrink fitting process, with end plates arranged on both sides in the axial direction. However, the rotor core 36 may be fixed to the rotor shaft RS by a method other than the shrink fitting process.

One end of the rotor shaft RS (the right end in the drawing) projects outward from the corresponding end plate and is paired by the case 2 via a bearing B1 held by a boss 211 formed in the first case 21. It is supported parallel to the drive shaft DS and rotatably. Further, the other end of the rotor shaft RS (the left end in the drawing) protrudes outward from the corresponding end plate and is held by a boss portion 221 formed on the partition wall 220 of the second case 22 via a bearing B2. It is rotatably supported by the case 2. As shown in FIG. 1, the boss portion 221 is formed in the partition wall 220 so as to surround the through hole 220o formed in the partition wall 220 and project toward the motor chamber M side. The bearings B1 and B2 are ball bearings including an outer race press-fitted into the recess of the boss portion 211 or 221, an inner race into which one end or the other end of the rotor shaft RS is press-fitted, and a plurality of balls. ..

As shown in FIG. 1, the input shaft IS is coaxially connected to the rotor shaft RS. In the present embodiment, one end of the input shaft IS (the right end in the drawing) passes through the through hole 220o of the partition wall 220 and protrudes into the motor chamber M, and is spline-fitted on the inner peripheral surface of the rotor shaft RS. Will be done. Further, one end of the input shaft IS is rotatably supported by the case 2 via a bearing B11 held by a boss portion 222 formed on the partition wall 220 of the second case 22. As shown in FIG. 1, the boss portion 222 is formed in the partition wall 220 so as to surround the through hole 220o and project toward the gear chamber G side. Further, the other end of the input shaft IS (the left end in the drawing), that is, the end opposite to the motor chamber M is held by the boss portion 232 formed on the wall portion of the third case 23 facing the partition wall 220. It is rotatably supported by the case 2 via the bearing B12. The bearings B11 and B12 are balls including an outer race Lo press-fitted into the recess of the boss portion 222 or 232, an inner race Li into which one end or the other end of the input shaft IS is press-fitted, and a plurality of balls B. It is a bearing.

The gear row 4 includes a counter drive gear (first drive gear) 41, a counter driven gear (first driven gear) 42, a drive pinion gear (final drive gear: second drive gear) 43, and a differential gear (final driven gear: second). Includes a differential gear 45 having a driven gear) 44. The counter drive gear 41 is an external tooth gear integrally formed with the input shaft IS. However, the counter drive gear 41, which is separate from the input shaft IS, may be fixed to the input shaft IS.

The counter-driven gear 42 is an external tooth gear having a diameter larger than that of the counter drive gear 41 that meshes with the counter drive gear 41. The counter-driven gear 42 is fixed to the counter shaft CS which is rotatably supported in parallel with the rotor shaft RS, the input shaft IS, and the pair of drive shafts DS by the case 2. The drive pinion gear 43 is an external tooth gear having a diameter smaller than that of the counter driven gear 42, which is integrally formed with the counter shaft CS so as to be located on the motor chamber M side of the counter driven gear 42. As a result, the drive pinion gear 43 rotates coaxially and integrally with the counter driven gear 42 and the counter shaft CS. However, a drive pinion gear 43 that is separate from the counter shaft CS may be fixed to the counter shaft CS.

As shown in FIG. 1, one end of the counter shaft CS (the right end in the drawing), that is, the end on the motor chamber M side is formed on the partition wall 220 of the second case 22 so as to project toward the gear chamber G side. It is rotatably supported by the case 2 via the bearing B21 held by the boss portion 224. Further, the other end of the counter shaft CS (the left end in the drawing), that is, the end opposite to the motor chamber M is held by the boss portion 234 formed on the wall portion of the third case 23 facing the partition wall 220. It is rotatably supported by the case 2 via the bearing B22. Bearings B21 and B22 are cones including an outer race Lo press-fitted into the recess of the boss portion 224 or 234, an inner race Li into which one end or the other end of the counter shaft CS is press-fitted, and a plurality of rollers R. Roller bearings (tapered roller bearings).

The differential ring gear 44 is an external gear that meshes with the drive pinion gear 43. The differential gear 45 supports a pair of (two) pinion gears 46, a pair of side gears 47 that are fixed to the drive shaft DS and mesh with the pair of pinion gears 46 at right angles, and a pair of pinion gears 46. It includes a pinion shaft 48 and a differential case 49 that accommodates a pair of pinion gears 46 and a pair of side gears 47 and to which the differential ring gear 44 is connected (fixed). In this embodiment, each pinion gear 46 and each side gear 47 are immediate bevel gears. Further, a pinion washer is arranged between each pinion gear 46 and the differential case 49, and a side washer is arranged between each side gear 47 and the differential case 49.

One end (right end in the drawing) of the differential case 49 in the axial direction is rotated by the case 2 via a bearing B31 held by a boss 226 formed in the second case 22 so as to project toward the gear chamber G side. It is supported freely. Further, the other end portion (left end portion in the drawing) of the differential case 49 in the axial direction is rotatably supported by the case 2 via the bearing B32 held by the boss portion 236 formed in the third case 23. Bearings B31 and B32 are conical roller bearings (conical roller bearings) including an outer race Lo press-fitted into the hole of the boss portion 226 or 236, an inner race Li into which the corresponding end of the differential case 49 is press-fitted, and a plurality of rollers R. Tapered roller bearing). As a result, the pair of drive shafts DS are also rotatably supported by the case 2 via the bearings B31 and B32.

FIG. 2 is a front view of the vehicle drive device 1 from which the cover 24 has been removed as viewed from the motor chamber M side. As described above, the partition wall 220 of the second case 22 included in the case 2 of the vehicle drive device 1 has a plurality of bolt holes H for fixing the stator 30 (stator core 31) in the motor chamber M (this implementation). In the form, three) are formed. Of the plurality of bolt holes H formed on the motor chamber M side of the partition wall 220, one shown in FIG. 2 is shown by a broken line in the figure when viewed from the axial direction of the motor generator 3 (viewed from the cover 24 side). It is included in the first range A.

The first range A is the outer circumference of the bearing B21 (first bearing) that supports the counter shaft CS as the first shaft and one of the second shafts different from the counter shaft CS when viewed from the axial direction of the motor generator 3. A line segment connecting the two common tangent lines T1 and T2 on the outer circumference of the bearing B31 (second bearing) supporting the drive shaft DS and the contacts between the outer circumference of the bearing B21 and the two common tangent lines T1 and T2. It is a quadrangular range surrounded by L1 and a line segment L2 connecting the outer periphery of the bearing B31 and the contact points of the two common tangent lines T1 and T2. Here, the outer circumference of the bearing B21 is defined by the outer circumference circle of the outer race Lo of the bearing B21 or the inner circumference circle of the boss portion 224 holding the outer race Lo, and the outer circumference of the bearing B31 is the outer race of the bearing B31. It is defined by the outer circumference circle of Lo or the inner circumference circle of the boss portion 225 holding the outer race Lo.

Further, in the present embodiment, the one bolt hole H is also included in the second range a shown by the alternate long and short dash line in FIG. 2 when viewed from the axial direction of the motor generator 3. The second range a is the contact points between the two common circumscribed lines T3 and T4 on the outer circumference of the counter shaft CS and the outer circumference of the drive shaft DS, and the contacts between the outer circumference of the counter shaft CS and the two common circumscribed lines T3 and T4. It is a quadrangular range surrounded by the line segment L3 connecting the line segment L3 and the line segment L4 connecting the outer periphery of the drive shaft DS and the contacts of the two common circumscribed lines T3 and T4. The second range a may be defined by using the inner circumference circle of the inner race Li of the bearing B21 and the inner circumference circle of the inner race Li of the bearing B31 instead of the outer circumferences of the counter shaft CS and the drive shaft DS. good. Further, in the present embodiment, the head 33h of the bolt 33 screwed into the one bolt hole H has the axis of the counter shaft CS and the axis of the drive shaft DS when viewed from the axial direction of the motor generator 3. It overlaps with the connecting line segment L0.

As a result, in the vehicle drive device 1, the partition wall around the bearings B21 and B31, that is, around the boss portions 224 and 226, by utilizing the rigidity (annular rigidity) of the stator 30 (stator core 31) fastened to the partition wall 220. By increasing the rigidity of 220, it is possible to satisfactorily suppress deformation of the boss portions 224 and 226 and the partition wall 220 around them. Therefore, the support rigidity of the counter shaft CS by the bearing B21 and the support rigidity of the drive shaft DS by the bearing B31 without increasing the thickness of the partition wall 220 or forming ribs on the partition wall 220 around the bearings B21 and B31. Can be enhanced. As a result, the gear train 4 suppresses the eccentricity of the counter shaft CS and the drive shaft DS while suppressing the increase in size (and weight increase) and cost of the vehicle drive device 1 including the motor generator 3 and the gear train 4. It is possible to satisfactorily reduce the generated gear noise, particularly the gear noise generated between the drive pinion gear 43 rotating integrally with the counter shaft CS and the differential ring gear 44 supported coaxially with the drive shaft DS.

Further, in the vehicle drive device 1, the one bolt hole H is included in the second range a surrounded by two common circumscribed lines T3 and T4 and line segments L3 and L4 when viewed from the axial direction. As a result, the one bolt hole H can be brought closer to the bearings B21 and B31, that is, the boss portions 224 and 226, so that the deformation of the boss portions 224 and 226 and the partition wall 220 around them is improved. It becomes possible to suppress.

Further, in the vehicle drive device 1, the head 33h of the bolt 33 screwed into the one bolt hole H is the axis of the counter shaft CS and the axis of the drive shaft DS when viewed from the axial direction of the motor generator 3. It overlaps with the line segment L0 connecting with. As a result, the rigidity of the stator 30 makes it possible to increase the rigidity of the partition wall 220 around the bearings B21 and B31, that is, the boss portions 224 and 226. Further, depending on the structure of the vehicle drive device 1, the center of the one bolt hole H may overlap with the line segment L0 when viewed from the axial direction of the motor generator 3. As a result, the rigidity of the partition wall 220 around the boss portions 224 and 226 can be further increased.

In addition, the bearings B21 and B31 of the vehicle drive device 1 include an outer race Lo that is press-fitted into the boss portion 224 or 226 of the partition wall 220, respectively. This makes it possible to increase the rigidity around the bearings B21 and B31, that is, the boss portions 224 and 226 of the partition wall 220.

In the vehicle drive device 1, one bolt hole H is included in the first and second ranges A and a when viewed from the axial direction of the motor generator 3, but is not limited to this. That is, depending on the number of bolt holes H for fastening the stator 30 to the partition wall 220, the plurality of bolt holes H may be at least one of the first and second ranges A and a when viewed from the axial direction of the motor generator 3. It may be included in one of them.

Further, in the vehicle drive device 1, at least one bolt hole H is surrounded by two common circumscribed lines T1 and T2 and line segments L1 and L2 when viewed from the axial direction of the motor generator 3. And a second range a surrounded by two common circumscribed lines T3, T4, line segments L3 and L4, but is not limited to this.

That is, depending on the structure of the vehicle drive device 1, at least one bolt hole H is the outer periphery of the bearing B11 (first bearing) that supports the input shaft IS as the first shaft when viewed from the axial direction of the motor generator 3. Two common tangent wires on the outer circumference of the bearing B21 (second bearing) that supports the counter shaft CS as the second shaft, and a line segment connecting the contacts between the outer circumference of the bearing B11 and the two common tangent wires. , May be included in the range surrounded by the outer periphery of the bearing B21 and the line segment connecting the contact points of the two common tangent lines. Further, at least one bolt hole H is an input with two common circumscribed lines, that is, the outer circumference of the input shaft IS as the first shaft and the outer circumference of the counter shaft CS as the second shaft when viewed from the axial direction of the motor generator 3. Included in the range surrounded by the line segment connecting the outer circumference of the shaft IS and the contacts of the two common circumscribed lines and the line segment connecting the outer circumference of the counter shaft CS and the contacts of the two common circumscribed lines. May be.

Further, depending on the structure of the vehicle drive device 1, at least one bolt hole H is formed on the outer periphery of the bearing B11 (first bearing) that supports the input shaft IS as the first shaft when viewed from the axial direction of the motor generator 3. Two common tangent wires on the outer circumference of the bearing B31 (second bearing) that supports one drive shaft DS as the second shaft, and a line connecting the contacts between the outer circumference of the bearing B11 and the two common tangent wires. It may be included in the range surrounded by the minute and the line connecting the outer periphery of the bearing B31 and the contact points of the two common tangent lines. Further, at least one bolt hole H is an input with two common circumscribed lines, that is, the outer circumference of the input shaft IS as the first shaft and the outer circumference of the drive shaft DS as the second shaft when viewed from the axial direction of the motor generator 3. Included in the range surrounded by the line segment connecting the outer circumference of the shaft IS and the contacts of the two common circumscribed lines and the line segment connecting the outer circumference of the drive shaft DS and the contacts of the two common circumscribed lines. May be.

Further, in the vehicle drive device 1, a plurality of holes (fastening holes) as fastening portions may be formed in the partition wall 220 of the second case 22 instead of the plurality of bolt holes H, and the stator core 31 (stator). 30) may be fastened to the partition wall 220 via the plurality of holes and a rivet inserted through the through hole formed in the stator core 31 or a press-fit pin formed in the stator core 31.

The gear train 4 of the vehicle drive device 1 is not limited to the three-axis gear train including the counter shaft CS, and the present invention of the present disclosure is a two-axis gear train or four or more gears. It may be applied to a vehicle drive device including a gear train having a shaft.

As described above, the vehicle drive device of the present disclosure includes a rotary electric machine (3) including a stator (30) and a rotor (35), an input shaft (IS) coaxially connected to the rotor (35), and an input shaft (IS). A plurality of shafts including at least an output shaft (DS) connected to a drive wheel, a gear train (4) for transmitting power between the input shaft (IS) and the output shaft (DS), and the rotary electric machine. In the vehicle drive device (1) including the (3) and the case (2) accommodating the gear train (4), the inside of the case (2) is formed by the partition wall (220) to form the rotary electric machine (3). Is divided into a first chamber (M) in which the gear row (4) is arranged and a second chamber (G) in which the gear row (4) is arranged, and the stator (30) of the rotary electric machine (3) is the first chamber (30). It is fastened to the partition wall (220) via a plurality of fastening portions (H) formed in the partition wall (220) so as to open in the chamber (M), and the partition wall (220) is connected to the second chamber (G). On the) side, the first bearing (B21) that supports the first shaft (CS) of the plurality of shafts and the second shaft (DS) that is different from the first shaft (CS) of the plurality of shafts. ) Is held, and at least one of the plurality of fastening portions (H) of the first bearing (B21) is viewed from the axial direction of the rotary electric machine (3). Two common tangent wires (T1, T2) on the outer circumference and the outer circumference of the second bearing (B31), and the outer circumference of the first bearing (B21) and the two common tangent wires (T1, T2). A range surrounded by a line connecting the contacts (L1) and a line connecting the outer periphery of the second bearing (B31) and the contacts of the two common external wires (T1, T2) (L2). It is included in.

In the vehicle drive device of the present disclosure, the case includes a partition wall that divides the inside into a first chamber in which a rotary electric machine is arranged and a second chamber in which a gear train is arranged. Further, the partition wall of the case includes a plurality of fastening portions each opened in the first chamber, and the stator of the rotary electric machine is fastened to the partition wall via the plurality of fastening portions. Further, the partition wall includes a first bearing that supports the first shaft of the plurality of shafts and a second bearing that supports a second shaft that is different from the first shaft of the plurality of shafts on the second chamber side. To hold. Then, at least one of the plurality of fastening portions is two common external line segments, one on the outer circumference of the first bearing and the other on the outer circumference of the second bearing, and two on the outer circumference of the first bearing when viewed from the axial direction of the rotary electric machine. It is included in the range surrounded by the line segment connecting the contacts with the common tangent line of the above and the line segment connecting the contact points between the outer circumference of the second bearing and the two common tangent lines. As a result, the rigidity of the partition wall fastened to the partition wall (annular rigidity) is used to increase the rigidity of the partition wall around the first and second bearings, so that the partition wall is deformed around the first and second bearings. It becomes possible to suppress it satisfactorily. Therefore, in the vehicle drive device of the present disclosure, the support rigidity of the first shaft by the first bearing is not increased or ribs are formed on the partition wall around the first and second bearings. And the support rigidity of the second shaft by the second bearing can be increased. As a result, it is possible to suppress the eccentricity of the first and second shafts and reduce the noise generated in the gear train while suppressing the increase in size and cost of the vehicle drive device including the rotary electric machine and the gear train. It will be possible.

Further, the first and second bearings (B21, B31) may each include an outer race (Lo) press-fitted into the partition wall (220). This makes it possible to increase the rigidity of the partition wall around the first and second bearings.

Further, at least one of the plurality of fastening portions (H) has two common circumscribed lines (T3, T4) on the outer circumference of the first shaft (CS) and the outer circumference of the second shaft (DS). A line segment (L3) connecting the contact points between the outer circumference of the first shaft (CS) and the two common circumscribed lines (T3, T4), the outer circumference of the second shaft (DS), and the outer circumference. It may be included in the range surrounded by the line segment (L4) connecting the contact points with the two common circumscribed lines (T3, T4). As a result, at least one of the above fastening portions can be brought closer to the first and second bearings, so that deformation of the partition wall around the first and second bearings can be suppressed more satisfactorily.

Further, the fastening portion may be a bolt hole (H) into which a bolt (33) is screwed.

Further, the head portion (33h) of the bolt (33) screwed into at least one of the plurality of fastening portions (H) is the shaft of the first shaft (CS) when viewed from the axial direction. It may overlap with the line segment (L0) connecting the center and the axial center of the second shaft (DS). This makes it possible to increase the rigidity of the partition wall around the first and second bearings by the rigidity of the stator.

Further, the gear train (4) includes a first drive gear (41) that rotates integrally with the input shaft (IS), a first driven gear (42) that meshes with the first drive gear (41), and the above. A second drive gear (43) that rotates integrally with the first driven gear (42) and a second driven gear (44) that meshes with the second drive gear (43) are included and connected to the pair of output shafts (DS). The differential gear (45) may be included, and the plurality of shafts include a counter shaft (CS) that rotates integrally with the first driven gear (42) and the second drive gear (43). It may be included.

Further, the first shaft may be the counter shaft (CS), and the second shaft may be one of the pair of output shafts (DS). This makes it possible to satisfactorily reduce the gear noise generated between the second drive gear that rotates integrally with the counter shaft and the second driven gear of the differential gear.

It goes without saying that the invention of the present disclosure is not limited to the above-described embodiment, and various changes can be made within the scope of the extension of the present disclosure. Furthermore, the above-described embodiment is merely a specific embodiment of the invention described in the column of the outline of the invention, and does not limit the elements of the invention described in the column of the outline of the invention.

The invention of the present disclosure can be used in the manufacturing industry of a vehicle drive device including a rotary electric machine and a gear train.

1 Vehicle drive device, 2 cases, 21 1st case, 211 boss part, 22 2nd case, 220 partition wall, 220o through hole, 221,222, 224, 225, 226 boss part, 23 3rd case, 232, 234 , 236 Boss, 24 Cover, 25, 26, 27 Bolt, 3 Motor Generator, 30 Stator, 31 Stator Core, 32 Stator Coil, 33 Volt, 33h Head, 35 Rotor, 36 Rotor Core, 4 Gear Row, 41 Counter Drive Gear , 42 counter driven gear, 43 drive pinion gear, 44 differential gear, 45 differential gear, 46 pinion gear, 47 side gear, 48 pinion shaft, 49 differential case, B1, B2, B11, B12, B21, B22, B31, B32 bearing, L0, L1 , L2, L3, L4 line, T1, T2, T3, T4 common tangent line.

Claims (7)

Power is transmitted between a rotary electric machine including a stator and a rotor, a plurality of shafts including at least an input shaft coaxially connected to the rotor and an output shaft connected to a drive wheel, and the input shaft and the output shaft. In a vehicle drive device including the gear train to be used, the rotary electric machine, and a case for accommodating the gear train.
The inside of the case is divided by a partition wall into a first chamber in which the rotary electric machine is arranged and a second chamber in which the gear train is arranged.
The stator of the rotary electric machine is fastened to the partition wall via a plurality of fastening portions formed in the partition wall so as to open in the first chamber.
The partition wall supports a first bearing that supports the first shaft of the plurality of shafts and a second shaft that is different from the first shaft of the plurality of shafts on the second chamber side. Hold 2 bearings and
At least one of the plurality of fastening portions is the two common external line segments of the outer circumference of the first bearing and the outer circumference of the second bearing when viewed from the axial direction of the rotary electric machine, and the said one of the first bearings. It is included in the range surrounded by the line segment connecting the contacts of the outer circumference and the two common tangent lines and the line segment connecting the contacts of the outer circumference of the second bearing and the two common tangent lines. Vehicle drive device. In the vehicle drive device according to claim 1,
The first and second bearings are vehicle drive devices including outer races that are press-fitted into the partition wall, respectively. In the vehicle drive device according to claim 1 or 2.
At least one of the plurality of fastening portions includes two common circumscribed lines, that is, the outer circumference of the first shaft and the outer circumference of the second shaft, and the outer circumference of the first shaft when viewed from the axial direction. For vehicles included in the range surrounded by the line segment connecting the contacts with the two common circumscribed lines and the line segment connecting the contacts between the outer circumference of the second shaft and the two common circumscribed lines. Drive device. The vehicle drive device according to any one of claims 1 to 3, wherein the fastening portion is a bolt hole into which a bolt is screwed. In the vehicle drive device according to claim 4,
The head of the bolt screwed into at least one of the plurality of fastening portions is a line segment connecting the axial center of the first shaft and the axial center of the second shaft when viewed from the axial direction. Vehicle drive that overlaps with. In the vehicle drive device according to any one of claims 1 to 5.
The gear train includes a first drive gear that rotates integrally with the input shaft, a first driven gear that meshes with the first drive gear, a second drive gear that rotates integrally with the first driven gear, and the second drive gear. It includes a second driven gear that meshes with the drive gear and a differential gear that is connected to the pair of output shafts.
The plurality of shafts are vehicle drive devices including a counter shaft that rotates integrally with the first driven gear and the second drive gear. In the vehicle drive device according to claim 6,
The first shaft is the counter shaft, and the second shaft is a vehicle drive device which is one of the pair of output shafts.

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