CN118451637A - Driving device - Google Patents

Abstract

An inverter case of the drive device is attached to one axial end of the motor case and surrounds the inverter unit. The interior of the inverter housing is connected to the interior of the motor housing. In addition, the inner sheath forms a fluid path with the motor barrel of the motor housing. The 1 st bearing holder is attached to one axial end of the inner sheath, and holds the 1 st bearing rotatably supporting one axial side portion of the shaft. A stator is retained on a radially inner side of the inner sheath.

Description

Driving device

Technical Field

The present invention relates to a driving device.

The present application claims priority based on japanese patent application No. 2021-214266, invented in japan, 12 months of 2021, 28, the contents of which are incorporated herein by reference.

Background

Conventionally, a motor having a flow path through which a refrigerant flows is known. For example, the shaft of the motor is rotatably supported by a1 st bearing provided to the 1 st housing member and a2 nd bearing provided to the 2 nd housing member to which the 1 st housing member is fixed. The refrigerant flow path is formed between the stator core holding frame of the stator and the cylindrical portion of the 2 nd housing member to which the stator is fixed. (refer to Japanese patent laid-open publication No. 2014-165986)

In recent years, a driving device is known in which a motor and a gear portion for transmitting torque of the motor to a drive shaft are housed in a housing.

Prior art literature

Patent literature

Patent document 1: japanese patent laid-open publication No. 2014-165986

Disclosure of Invention

Problems to be solved by the invention

If the motor having the above-described refrigerant flow path is to be mounted on the driving device, the number of housing members constituting the housing increases, and accordingly, the axial dimension of the driving device tends to increase. For example, a motor housing, a gear housing, and a motor bearing holder attached to an axial end portion of the motor housing are arranged in an axial direction of the drive device.

The purpose of the present invention is to suppress an increase in the axial dimension of a drive device.

Means for solving the problems

An exemplary drive device of the present invention has a shaft, a rotor, a stator, an inverter unit, and a housing. The shaft extends in an axial direction along the rotation axis. The rotor is fixed to the shaft and rotatable together with the shaft about the rotation axis. The stator is disposed radially outward of the rotor. The inverter unit supplies power to the stator. The housing accommodates the shaft, the rotor, the stator, and the inverter unit. The housing has a motor housing, an inverter housing, an inner jacket, a fluid passage, a1 st bearing, and a1 st bearing retainer. The motor housing has a motor barrel. The motor cylinder portion has a cylindrical shape extending in an axial direction and surrounds the rotor and the stator. The inverter case is attached to one axial end of the motor case and surrounds the inverter unit. The inner sheath extends axially and is located on the radially inner side of the motor barrel. The fluid passage is surrounded by the motor cartridge and the inner sheath. The fluid passageway is capable of fluid communication. The 1 st bearing rotatably supports a portion of the shaft on one axial side. The 1 st bearing holder is attached to one axial end of the inner sheath, and holds the 1 st bearing. The stator is retained on a radially inner side of the inner jacket. One axial end of the motor housing is opened. The interior of the inverter housing is connected to the interior of the motor housing.

Effects of the invention

According to the exemplary driving device of the present invention, an increase in the axial dimension of the driving device can be suppressed.

Drawings

Fig. 1 is a cross-sectional view showing a schematic configuration of a driving device.

Fig. 2 is an external view of the driving device.

Fig. 3 is an enlarged view of a portion X surrounded by a broken line of fig. 1.

Fig. 4 is a schematic diagram showing an example of a vehicle mounted with a driving device.

Fig. 5 is an exploded perspective view of the housing.

Fig. 6A is an external view showing a structural example of the inner sheath.

Fig. 6B is a cross-sectional view of the inner sheath.

Fig. 7 is an external view showing another configuration example of the inner sheath.

Fig. 8 is a diagram showing a configuration example of the 1 st connection portion and the 2 nd connection portion.

Detailed Description

Hereinafter, exemplary embodiments will be described with reference to the drawings.

In the present specification, the direction parallel to the rotation axis J1 in the driving device 100 is referred to as an "axial direction". The direction from the motor 1 to the inverter unit 3 in the axial direction is referred to as "one axial direction D1", and the direction from the inverter unit 3 to the motor 1 is referred to as "the other axial direction D2". In addition, in the predetermined member, the direction from the center portion to the end portion in the axial direction may be referred to as "axially outward Do". In addition, in the predetermined member, the direction from the end portion to the center portion in the axial direction is sometimes referred to as "axial inward Di".

The direction perpendicular to a predetermined axis such as the rotation axis J1 is referred to as a "radial direction", and the rotation direction around the predetermined axis is referred to as a "circumferential direction". The direction closer to the predetermined axis in the radial direction is referred to as "radially inward", and the direction farther from the predetermined axis is referred to as "radially outward".

In the present specification, the term "annular" includes a shape in which the entire circumferential region centered on a predetermined axis such as the rotation axis J1 is continuously connected as a unit without slits, and a shape in which 1 or more slits are provided in a part of the entire circumferential region centered on the predetermined axis. Further, the present invention includes a method of drawing a closed curve on a curved surface intersecting a predetermined axis line.

In the present specification, "tubular" also includes a case where the cross-section viewed from the direction in which the tubular shape extends is not circular. For example, the "tubular" cross-sectional shape may be an n-sided shape (n is a positive integer of 2 or more), or may be a circular shape, an elliptical shape, or the like.

In addition, the term "parallel" in the positional relationship between any one of the azimuth, the line, and the plane and any other one includes not only a state where both extend completely without intersecting, but also a substantially parallel state. In addition, "perpendicular" and "orthogonal" include not only a state in which both intersect each other at 90 degrees, but also a substantially perpendicular state and a substantially orthogonal state, respectively. That is, the terms "parallel", "perpendicular" and "orthogonal" include a state in which the positional relationship of the two is angularly offset to an extent that does not deviate from the gist of the present invention.

These are names used for the purpose of illustration only, and are not intended to limit the actual positional relationship, directions, names, and the like.

< 1. Drive device 100 >)

Fig. 1 is a cross-sectional view showing a schematic configuration of a driving device 100. Fig. 2 is an external view of the driving device 100. Fig. 3 is an enlarged view of a portion X surrounded by a broken line of fig. 1. Fig. 4 is a schematic diagram showing an example of a vehicle 300 on which the drive device 100 is mounted. Fig. 1 to 4 are conceptual views, and the arrangement and size of each component are not necessarily the same as those of the actual driving device 100.

The driving device 100 is mounted on a vehicle 300 (see fig. 4) that uses at least a motor as a power source. The vehicle 300 is a Hybrid Vehicle (HV), a plug-in hybrid vehicle (PHV), an Electric Vehicle (EV), or the like. The drive device 100 is used as a power source of the vehicle 300 described above. In fig. 4, the driving device 100 drives the front wheels of the vehicle 300. However, the present invention is not limited to the example of fig. 4, and the driving device 100 may drive at least one of the front wheels and the rear wheels. The vehicle 300 has the drive device 100 and the battery 200. The battery 200 stores electric power for supplying the drive device 100.

As shown in fig. 1 and 2, the driving device 100 includes a motor 1, a gear portion 2, an inverter unit 3, a rotation detector 4, and a housing 5.

< 1-1 Motor 1 >)

The motor 1 is a driving source of the driving device 100, and is of an inner rotor type in which a rotor 11 is rotatably disposed radially inward of a stator 12. As shown in fig. 1, the motor 1 includes a motor shaft 10, a rotor 11, a stator 12, and a pair of fans 13.

1-1-1 Motor shaft 10>

The motor shaft 10 extends in the axial direction along the rotation axis J1, and is rotatable about the rotation axis J1. In the present embodiment, the motor shaft 10 is a split shaft that is split into two parts, and is composed of the rotor shaft 110 and the gear shaft 210.

The rotor shaft 110 holds a rotor core 111 described later. The rotor core 111 is fixed to a radially outer side surface of the rotor shaft 110. Rotor shaft 110 extends in the axial direction along rotation axis J1. Rotor shaft 110 is an example of the "shaft" of the present invention. The drive 100 has a rotor shaft 110. A gear shaft 210 is connected to the other end portion of the rotor core 111 in the axial direction D2.

The gear shaft 210 is connected to the gear portion 2. An end portion of the gear shaft 210 on the one axial direction D1 side is spline-fitted to an end portion of the rotor shaft 110 on the other axial direction D2 side. However, the present invention is not limited to this example, and the rotor shaft 110 and the gear shaft 210 may be coupled by a screw coupling using external screw and internal screw, or may be coupled by a fixing method such as press fitting or welding. In the case of using a fixing method such as press fitting or welding, a serration may be used in which concave portions and convex portions extending in the axial direction are combined. By adopting such a structure, rotation can be reliably transmitted from the rotor shaft 110 to the gear shaft 210.

The present invention is not limited to the example of the present embodiment, and the motor shaft 10 may be a single member. In this case, the motor shaft 10 corresponds to the "shaft" of the present invention.

1-1-2 Rotor 11 >

The rotor 11 is driven by the stator 12 and is rotatable about the rotation axis J1. The rotor 11 is fixed to the rotor shaft 110 and is rotatable together with the rotor shaft 110 around the rotation axis J1. The drive device 100 has a rotor 11.

The rotor 11 includes a rotor core 111, a magnet 112, and a through hole 113.

The rotor core 111 is a magnetic body, and is formed by stacking, for example, thin-plate electromagnetic steel plates in the axial direction. The rotor core 111 surrounds the rotor shaft 110 and is fixed to a radially outer surface of the rotor shaft 110.

A plurality of magnets 112 are fixed to the rotor core 111. The plurality of magnets 112 are radially opposed to the stator 12 such that the magnetic poles are alternately arranged along the circumferential direction.

A through hole 113 extending in the axial direction is disposed in the rotor core 111. The through-holes 113 extend through the rotor core 111 in the axial direction, and in the present embodiment, are arranged in a plurality in the circumferential direction. By disposing the through holes 113, a passage through which air can flow can be disposed inside the rotor core 111. Therefore, the rotor 11 can be air-cooled from the inside of the rotor 11.

Preferably, the through hole 113 is disposed radially inward of the magnet 112 when viewed from the axial direction. In this way, the through hole 113 can be arranged without the magnet 112 interfering with the magnetic circuit formed in the rotor 11.

In the present embodiment, the number of through holes 113 is plural. Preferably, the through holes 113 are arranged at equal intervals in the circumferential direction. In this way, the rotor 11 can be cooled more uniformly. However, this example does not exclude a configuration in which the through holes 113 are arranged at different intervals in the circumferential direction, nor does it exclude a configuration in which the through holes 113 are single.

1-1-3 Stator 12>, stator

The stator 12 is disposed radially outward of the rotor. The drive device 100 has a stator 12. The stator 12 is annular and surrounds the rotor 11, and faces the rotor 11 with a gap therebetween in the radial direction. The stator 12 rotates the rotor 11 in accordance with the power supply from the inverter unit 3. The stator 12 is held by the housing 5. In detail, the stator 12 is held on a radially inner side surface of the inner sheath 6 described later.

The stator 12 includes a stator core 121, a coil portion 122, and an insulator 123. The stator core 121 has a plurality of magnetic pole teeth (not shown) radially inward from an inner peripheral surface of the annular yoke. The insulator 123 has electrical insulation properties, and is interposed between the stator core 121 and the coil portion 122. A coil wire is wound between the pole teeth with an insulator 123 interposed therebetween. The coil wire wound around the magnetic pole teeth constitutes the coil portion 122. The coil wire is connected to the inverter unit 3 via a bus bar, not shown.

The coil portion 122 has a pair of coil heads 1221. The pair of coil heads 1221 is located axially outward Do of the stator core 121. Specifically, the coil head 1221 on the one D1 side in the axial direction of the pair of coil heads 1221 is located closer to the one D1 side in the axial direction than the stator core 121. The coil head 1221 on the other axial direction D2 side is located closer to the other axial direction D2 than the stator core 121.

1-1-4 Fan 13 >)

A pair of fans 13 are disposed at axial ends of the rotor 11. Specifically, one of the pair of fans 13 is disposed at one end portion of the rotor 11 on the axial direction D1 side. The other fan 13 is disposed at the other end of the rotor 11 on the other axial side D2.

The fan 13 is rotatable with the rotor 11 around the rotation axis J1. By the rotation of the fan 13, air can be blown to the stator 12 (particularly, the coil portion 122), and therefore, the cooling efficiency of the stator 12 can be improved. Further, since the air in the motor housing space Sm described later can be stirred, the air in the vicinity of the inner sheath 6 constituting the fluid passage 7 can be replaced. This allows, for example, replacement of the air in contact with the inner sheath 6, and therefore, the heat radiation efficiency from the air passing through the inner sheath 6 to the fluid F in the fluid passage 7 can be improved. Therefore, the motor 1 of the driving device 100 can be cooled efficiently. Further, since the cooling structure can be simply configured, the driving device 100 and the motor 1 can be prevented from being enlarged.

Preferably, as in the present embodiment, the fan 13 is a centrifugal fan. In this way, air can be blown radially from the fan 13, and therefore the cooling efficiency of the stator 12 can be further improved. But this illustration does not exclude that the fan 13 is not a centrifugal fan structure.

1-2 Gear part 2

Next, the gear portion 2 is connected to the other axial direction D2 side of the motor shaft 10, and in the present embodiment, to the gear shaft 210. As described above, the driving device 100 has the gear portion 2. The gear portion 2 is a power transmission device that transmits power of the motor 1 to a drive shaft Ds described later. The gear portion 2 has a reduction gear 21 and a differential gear 22.

1-2-1 Speed reducer 21 >

The reduction gear 21 is connected to the gear shaft 210. The speed reduction device 21 reduces the rotation speed of the motor 1, and increases the torque output from the motor 1 according to the reduction ratio of the speed reduction device 21. The reduction gear 21 transmits the torque output from the motor 1 to the differential gear 22. The reduction gear 21 has a 1 st gear 211, a2 nd gear 212, a 3 rd gear 213, and an intermediate shaft 214.

The 1 st gear 211 is fixed to the radially outer surface of the motor shaft 10 on the other axial direction D2 side of the motor shaft 10. For example, the 1 st gear 211 is disposed on the radially outer side surface of the gear shaft 210. The 1 st gear 211 may be integral with the gear shaft 210 or may be separate from the gear shaft 210 and firmly fixed to the radially outer side surface of the gear shaft 210. The 1 st gear 211 is rotatable together with the motor shaft 10 about the rotation axis J1.

The intermediate shaft 214 extends along the intermediate axis J2 and is rotatable about the intermediate axis J2. The intermediate axis J2 is parallel to the rotation axis J1, and extends in the axial direction. Both ends of the intermediate shaft 214 are supported by the 1 st intermediate bearing 5241 and the 2 nd intermediate bearing 5741 so as to be rotatable about the intermediate axis J2.

The 2 nd gear 212 and the 3 rd gear 213 are fixed to the radially outer side surface of the intermediate shaft 214, and are rotatable together with the intermediate shaft 214 about the intermediate axis J2. The 2 nd gear 212 and the 3 rd gear 213 may be integrated with the intermediate shaft 214, or may be separately and firmly fixed to the radial outer side surface of the intermediate shaft 214 from the intermediate shaft 214. The 2 nd gear 212 is meshed with the 1 st gear 211. The 3 rd gear 213 is disposed at a position closer to the one axial direction D1 than the 2 nd gear, and meshes with a 4 th gear 221 of the differential device 22, which will be described later.

Torque of the motor shaft 10 is transmitted from the 1 st gear 211 to the 2 nd gear 212. Then, the torque transmitted to the 2 nd gear 212 is transmitted to the 3 rd gear 213 via the intermediate shaft 214. Torque is transmitted from the 3 rd gear 213 to the 4 th gear 221 of the differential device 22.

1-2-2 Differential device 22>

The differential device 22 is attached to the drive shaft Ds, and transmits the torque transmitted from the reduction gear 21 to the drive shaft Ds. The differential device 22 has a4 th gear 221. The 4 th gear 221 is a so-called ring gear, and meshes with the 3rd gear 213. The torque of the 4 th gear 221 is output to the drive shaft Ds.

The drive shaft Ds has a1 st drive shaft Ds1 and a2 nd drive shaft Ds2. The 1 st drive shaft Ds1 is attached to one side D1 of the differential device 22 in the axial direction. The 2 nd drive shaft Ds2 is attached to the other axial direction D2 side of the differential device 22. The differential device 22 transmits torque to the drive shafts Ds1, ds2 while absorbing the rotational speed difference of the drive shafts Ds1, ds2 when the vehicle 300 turns, for example.

1-3 Inverter unit 3 >)

The inverter unit 3 supplies electric power to the stator 12. As described above, the driving apparatus 100 has the inverter unit 3. The inverter unit 3 is disposed at a position closer to the motor 1 than the motor 1 in the axial direction D1.

The inverter unit 3 has a1 st electronic circuit 31, a 2 nd electronic circuit 32, and an electronic substrate 33.

The 1 st electronic circuit 31 includes a capacitor 311. In detail, the inverter unit 3 further has a capacitor 311 and a substrate 312. The capacitor 311 is, for example, a film capacitor, an electrolytic capacitor, or the like. The substrate 312 expands in a direction intersecting the axial direction. The 1 st electronic circuit 31 is disposed on the substrate 312.

The 2 nd electronic circuit 32 includes a switching element 321. In detail, the inverter unit 3 further has a switching element 321 and a substrate 322. The switching element 321 is, for example, an IGBT, a SiC transistor element, or the like. The base plate 322 expands in a direction intersecting the axial direction. The 2 nd electronic circuit 32 is disposed on the substrate 322 and is electrically connected to the coil portion 122 of the stator 12 via a wiring 323 such as a three-phase line.

The electronic substrate 33 is electrically connected to the 1 st electronic circuit 31 and the 2 nd electronic circuit 32. A control unit (not shown) of the stator 12 and the like are mounted on the electronic board 33. For example, an arithmetic device such as an MPU (Micro Controller Unit: micro controller unit) is disposed on the electronic board 33.

Preferably, the 1 st electronic circuit 31, the 2 nd electronic circuit 32, and the electronic substrate 33 are arranged in the axial direction. In the present embodiment, the 1 st electronic circuit 31 including the capacitor 311, the substrate 312, the 2 nd electronic circuit 32 including the switching element 321, the substrate 322, and the electronic substrate 33 are sequentially arranged from the axial direction one D1 (the inverter unit 3 side) toward the axial direction other D2 (the motor 1 side). In this way, the 1 st electronic circuit 31, the 2 nd electronic circuit 32, and the electronic substrate 33 can be electrically connected more easily than in a structure in which they are arranged in the radial direction. In addition, this illustration does not exclude a structure in which at least a part of the 1 st electronic circuit 31, the 2 nd electronic circuit 32, and the electronic substrate 33 is not arranged in the axial direction with another part.

More preferably, the electronic substrate 33 is disposed closer to the other side D2 than the 1 st electronic circuit 31 and the 2 nd electronic circuit 32. By positioning the electronic substrate 33 on the other axial direction D2 side, the electronic substrate 33 can be disposed at a position closer to the fluid passage 7 described later in the axial direction. Therefore, since the temperature rise of the electronic substrate 33 can be suppressed, the influence of heat on devices such as the arithmetic device disposed on the electronic substrate 33 can be reduced. The above example does not exclude a configuration in which the electronic substrate 33 is not disposed at the other side D2 in the axial direction than the 1 st electronic circuit 31 and the 2 nd electronic circuit 32.

Further, it is more preferable that the 1 st electronic circuit 31 is arranged at a position closer to the axial direction D1 than the 2 nd electronic circuit 32. By disposing the 1 st electronic circuit 31 at a position closer to the axial direction D1 than the 2 nd electronic circuit 32, the 1 st electronic circuit 31 including the capacitor 311 can be disposed at a position closest to the axial direction D1. Therefore, even if the capacitor 311 is a large-sized element, a sufficient space for disposing the 1 st electronic circuit 31 can be ensured. Further, the 2 nd electronic circuit 32 connected to the stator 12 via the wiring 323 or the like can be disposed closer to the stator 12. The 2 nd electronic circuit 32 includes a switching element 321 such as an IGBT. Thus, for example, the length of the wiring 323 between the stator 12 and the 2 nd electronic circuit 32 can be further shortened. That is, the electrical connection between the two can be made easier. The above example does not exclude a configuration in which the 1 st electronic circuit 31 is not disposed at a position closer to the axial direction D1 than the 2 nd electronic circuit 32.

1-4 Rotation detector 4>

Next, the rotation detector 4 detects the rotation angle of the motor shaft 10. In the present embodiment, the rotation detector 4 is a resolver having a resolver rotor and a resolver stator. The rotation detector 4 includes a resolver rotor (not shown) and a resolver stator (not shown). The resolver rotor is fixed to rotor shaft 110. The resolver stator is fixed to the other axial direction D2 side of an inner bearing holder 8 described later of the housing 5.

The resolver rotor and the resolver stator are annular around the rotor shaft 110. The inner peripheral surface of the resolver stator is radially opposed to the outer peripheral surface of the resolver rotor. The resolver stator periodically detects the rotational angle position of the resolver rotor as the rotor 11 rotates. Thereby, the rotation detector 4 acquires information of the rotation angle position of the rotor 11.

The rotation detector 4 is not limited to the example of the present embodiment, and may be a rotary encoder, for example, instead of a resolver.

< 1-5 Shell 5 >

Next, the structure of the housing 5 will be described with reference to fig. 1 to 3 and 5. Fig. 5 is an exploded perspective view of the housing 5.

The housing 5 houses the motor 1, the gear portion 2, and the like. In particular, the housing 5 houses the rotor shaft 110, the rotor 11, the stator 12, and the inverter unit 3. As described above, the driving device 100 has the housing 5.

The housing 5 has a motor housing 501, a gear housing 502, and an inverter housing 503. The housing 5 further has an inner jacket 6, a fluid passage 7 and an inner bearing holder 8.

< 1-5-1. Motor housing 501 >)

The motor housing 501 includes a motor cylinder 51, a1 st side plate 52, and a 2 nd side plate 53. The end of the motor housing 501 on the axial direction one D1 side is open.

1-5-1-1 Motor cylinder 51 >

The motor cylinder 51 is formed in a tubular shape extending in the axial direction, and surrounds the motor 1. For example, the motor cylinder 51 surrounds the rotor shaft 110, the rotor 11, the stator 12, and the like. As described above, the motor housing 501 has the motor cylinder 51. Further, an inner sheath 6 is disposed on the radially inner side surface of the motor cylinder 51. The fluid passage 7 is formed between the motor cylinder 51 and the inner sheath 6.

The motor cylinder 51 has an inflow port 511 and an outflow port 512. The inlet 511 and the outlet 512 penetrate the motor cylinder 51 in the radial direction, and connect the fluid passage 7 to the outside of the housing 5.

The inflow port 511 is connected to a pump (not shown) that supplies the fluid F flowing through the fluid passage 7. The fluid F flows from the pump into the fluid passage 7 through the inflow port 511. In the present embodiment, the pump is mounted on the vehicle 300, and the fluid F is also supplied to a component mounted on the vehicle 300 that is different from the drive device 100. However, the present invention is not limited to this example, and the pump may be dedicated to the driving device 100. The pump may or may not be a constituent of the driving device 100.

The fluid F flows out from the fluid passage 7 to the outside thereof through the outflow port 512. For example, the outflow port 512 is connected to a tank (not shown) for storing the fluid F.

< 1-5-1-2. 1 St side plate portion 52 >)

The 1 st side plate 52 extends radially inward from the other end of the motor cylinder 51 on the axial direction D2 side, and holds the 1 st motor bearing 5221. The 1 st motor bearing 5221 rotatably supports the other axial portion D2 side of the rotor shaft 110. The 1 st side plate 52 is an example of the "2 nd bearing holder" of the present invention. The motor housing 501 has the 1 st motor bearing 5221, and has the 1 st side plate portion 52 as described above. In this way, the drive device 100 can rotatably support the rotor shaft 110 by the inner bearing holder 8 attached to the end portion of the inner sheath 6 on the one axial direction D1 side and the 1 st side plate portion 52 of the motor housing 501 forming the fluid passage 7 together with the inner sheath 6. In the present embodiment, the 1 st side plate portion 52 is integral with the motor cylinder portion 51. However, the present invention is not limited to this example, and the two may be different members.

The 1 st side plate portion 52 includes a plate portion 520, an insertion hole 521, a1 st motor bearing holder 522, a1 st gear bearing holder 523, and a1 st intermediate bearing holder 524.

The plate 520 is formed in a plate shape extending in a direction intersecting the rotation axis J1, and covers an end of the motor cylinder 51 on the other axial side D2.

The penetration hole 521 penetrates the plate portion 520 in the axial direction. The center of the penetration hole 521 coincides with the rotation axis J1. The motor shaft 10 is rotatably inserted through the insertion hole 521.

A 1 st motor bearing holder 522 for holding the 1 st motor bearing 5221 is disposed on one side D1 in the axial direction of the insertion hole 521.

A 1 st gear bearing holder 523 for holding the 1 st gear bearing 5231 is disposed on the other axial side D2 of the insertion hole 521. The 1 st gear bearing 5231 rotatably supports an end portion of the gear shaft 210 on the one axial direction D1 side.

The 1 st intermediate bearing holder 524 is disposed on the other end surface of the plate portion 250 in the axial direction D2 side, and holds the 1 st intermediate bearing 5241. The 1 st intermediate bearing 5241 rotatably supports an end portion of the intermediate shaft 214 on the one axial direction D1 side.

< 1-5-1-3. 2 Nd side plate portion 53 >)

The 2 nd side plate portion 53 is disposed at the radially outer end of the motor cylinder portion 51. In the present embodiment, the 2 nd side plate 53 is integral with the motor cylinder 51. However, the present invention is not limited to this example, and the two may be different members.

The 2 nd side plate portion 53 includes a plate portion 530, a1 st drive shaft insertion hole 531, a1 st drive bearing holder 532, and a1 st drive bearing 5321.

The plate 530 extends radially outward from the radially outer end of the motor cylinder 51.

The 1 st drive shaft penetration hole 531 penetrates the plate portion 530 in the axial direction. The center of the 1 st drive shaft insertion hole 531 coincides with the differential axis J3. The 1 st drive shaft Ds1 is rotatably inserted through the 1 st drive shaft insertion hole 531.

The 1 st drive bearing holder 532 is disposed in the 1 st drive shaft insertion hole 531. The 1 st drive bearing holder 532 holds the 1 st drive bearing 5321. The 1 st drive bearing 5321 rotatably supports the 1 st drive shaft Ds 1.

1-5-2 Gear case 502 >

The gear housing 502 is disposed on the other axial side D2 of the motor housing 501. The gear housing 502 has a gear cylinder portion 54 and a gear cover portion 55.

1-5-2-1 Gear cylinder 54 >

The gear tube 54 is in the form of a tube extending in the axial direction, and surrounds the gear portion 2. In the present embodiment, the gear cylinder 54 is attached to the end of the 1 st side plate 52 and the 2 nd side plate 53 on the other axial direction D2 side. A part of the gear tube 54 extends from the end of the plate 520 of the 1 st side plate 52 on the axial direction other side D2 side toward the axial direction other side D2. The remaining part of the gear tube 54 extends from the end of the plate 530 of the 2 nd side plate 53 on the axial direction other side D2 side toward the axial direction other side D2.

1-5-2-2 Gear cover 55 >, gear cover

The gear cover 55 covers the other axial end D2 side of the gear tube 54. In the present embodiment, the gear cover portion 55 is integral with the gear tube portion 54. However, the present invention is not limited to this example, and the two may be different members.

The gear cover 55 includes a cover 550, a 2 nd gear bearing holder 551, a 2 nd intermediate bearing holder 552, a 2 nd drive shaft insertion hole 553, and a 2 nd drive bearing holder 554.

The cover 550 is disposed at the other end of the gear tube 54 in the axial direction D2.

The 2 nd gear bearing retainer 551 holds the 2 nd gear bearing 5511. The 2 nd gear bearing 5511 rotatably supports the end portion of the gear shaft 210 on the other axial direction D2 side.

The 2 nd intermediate bearing holder 552 holds the 2 nd intermediate bearing 5521. The 2 nd intermediate bearing 5521 rotatably supports the end portion of the intermediate shaft 214 on the other axial direction D2 side.

The 2 nd drive shaft insertion hole 553 axially penetrates the cover 550. The center of the 2 nd drive shaft insertion hole 553 coincides with the differential axis J3. The 2 nd drive shaft Ds2 is rotatably inserted through the 2 nd drive shaft insertion hole 553.

A2 nd drive bearing holder 554 is disposed in the 2 nd drive shaft insertion hole 553. The 2 nd drive bearing holder 554 holds a2 nd drive bearing 5541 that rotatably supports the 2 nd drive shaft Ds 2.

< 1-5-3 Inverter housing 503 >)

The inverter case 503 is disposed on one side D1 of the motor case 501 in the axial direction, and surrounds the inverter unit 3.

By attaching the inverter case 503 to the end portion on the one axial direction D1 side of the motor case 501, the end portion on the one axial direction D1 side of the motor case 501 may be closed without using a cover member such as a bearing holder. Therefore, the axial dimension of the drive device 100 can be further reduced while suppressing an increase in size, compared with a structure in which the end portion of the opening of the motor housing 501 on the axial direction one D1 side is closed by the cover member and the inverter housing 503 is attached to the end portion of the motor housing 501 on the axial direction one D1 side via the cover member. Therefore, the driving device 100 can be prevented from being enlarged.

Further, since the inverter case 503 is attached to the end portion of the motor case 501 on the one axial direction D1 side, the heat generated by the stator 12 can be less likely to be transmitted to the inverter unit 3 than in the case where the inverter case 503 is attached to the radially outer end portion of the motor case 501. That is, the inverter unit 3 can be thermally protected.

The inverter case 503 has an inverter tube portion 56 and an inverter cover portion 57.

1-5-3-1 Inverter tube 56 >

The inverter tube portion 56 has a tubular shape extending in the axial direction, and surrounds the inverter unit 3. The other axial end D2 of the inverter tube 56 is connected to the one axial end D1 of the motor tube 51. Hereinafter, the connecting portion between the two in the axial direction is sometimes referred to as "1 st connecting portion C1".

1-5-3-2 Inverter cover 57 >, and

The inverter cover 57 is formed in a plate shape extending in a direction intersecting the rotation axis J1, and covers an end portion of the inverter tube 56 on the one axial direction D1 side. In the present embodiment, the inverter cover 57 is integral with the inverter tube 56. However, the present invention is not limited to this example, and the two may be different members.

1-5-4. Inner space of housing 5 >, inner space of housing

The housing 5 has a motor housing space Sm, a gear housing space Sg, and an inverter housing space Si.

The motor housing space Sm is a space surrounded by the motor cylinder 51 and the 1 st side plate 52. The motor housing space Sm houses the motor 1, the inner sheath 6, the fluid passage 7, and the inner bearing holder 8.

The gear housing space Sg is a space surrounded by the motor cylinder 51, the 1 st side plate 52, the 2 nd side plate 53, the gear cylinder 54, and the gear cover 55. The gear housing space Sg houses the gear portion 2. The gear housing space Sg is partitioned from the motor housing space Sm by the motor cylinder portion 51 and the 1 st side plate portion 52.

The inverter housing space Si is an internal space of the inverter case 503, is surrounded by the inverter tube portion 56 and the inverter cover portion 57, and houses the inverter unit 3. In the present embodiment, the inverter housing space Si is connected to the motor housing space Sm. That is, the inside of the inverter housing 503 is connected to the inside of the motor housing 501. In this way, the stator 12 in the motor case 501 can be electrically connected to the inverter unit 3 in the inverter case 503 without requiring a relay terminal block or the like.

1-5-5 Inner sheath 6>

Next, the inner sheath 6 will be described with reference to fig. 1,3, and 6A to 7. Fig. 6A is an external view showing a structural example of the inner sheath 6. Fig. 6B is a sectional view of the inner sheath 6. Fig. 7 is an external view showing another configuration example of the inner sheath 6.

The inner sheath 6 extends in the axial direction and is located on the radially inner side of the motor cylinder 51. The housing 5 also has an inner sheath 6. In the present embodiment, the inner sheath 6 has a tubular shape extending in the axial direction, and is held on the radially inner surface of the motor tubular portion 51. Further, the inner sheath 6 is not limited to the example of the present embodiment, and may be a plate-like member extending in the axial direction, and a plurality of inner sheaths may be arranged in a circumferential direction.

The inner sheath 6 has a1 st sheath portion 61, a pair of 2 nd sheath portions 62, a fixing portion 63, a1 st protruding wall portion 64, a partition portion 65, and a rib 66.

The 1 st sheath portion 61 holds the stator 12 on the radially inner side surface. In the present embodiment, the 1 st sheath portion 61 has a tubular shape extending in the axial direction, and holds the stator core 121 on the radially inner side surface.

The pair of 2 nd sheath portions 62 protrude from the end portion of the 1 st sheath portion 61 on the axially outward Do side toward the axially outward Do, and are opposed to the coil head 1221 in the radial direction. For example, one of the pair of 2 nd sheath portions 62 protrudes from the end portion of the 1 st sheath portion 61 on the axial direction one D1 side toward the axial direction one D1, and faces the coil head 1221 on the axial direction one D1 side in the radial direction. The other of the pair of 2 nd sheath portions 62 protrudes from the end portion of the 1 st sheath portion 61 on the axial direction other side D2 toward the axial direction other side D2, and is radially opposed to the coil head 1221 on the axial direction other side D2.

The radially inner side surface of at least one of the pair of 2 nd jacket portions 62 includes a tapered surface 621. Tapered surface 621 expands radially outward as it faces axially outward Do. Thus, the end portion on the axially outer side Do side between the coil head 1221 and the 2 nd sheath portion 62 opens toward the outside thereof. Therefore, the exchange of air between the coil head 1221 and the 2 nd sheath portion 62 and the outside thereof can be made smoother. Therefore, the cooling efficiency of the coil head 1221 can be further improved.

The fixing portion 63 is disposed at the radially outer end of the 2 nd sheath portion 62 on the axial direction one side D1. The radially outer end of the fixing portion 63 contacts the radially inner side surface of the motor cylinder 51 of the motor housing 501. In the present embodiment, the fixing portion 63 has a cylindrical shape surrounding the rotation axis J1.

The fixing portion 63 is fixed to the motor housing 501. In the present embodiment, the fixing portion 63 is fastened to the motor cylinder 51 using a bolt or the like. However, the fixing means of the fixing portion 63 is not limited to this example, and the fixing portion 63 may be fixed by other means such as welding, brazing, or bonding.

The 1 st protruding wall 64 protrudes in the axial direction D1 at the end portion of the inner sheath 6 on the axial direction D1 side, and extends in the circumferential direction. As described above, the inner sheath 6 has the 1 st protruding wall portion 64. In the present embodiment, the 1 st protruding wall portion 64 is annular surrounding the rotation axis J1, and protrudes from the end portion of the fixing portion 63 on the axial direction one D1 side toward the axial direction one D1.

The partition 65 protrudes radially outward at the radially outer end of the inner sheath 6 and extends in the circumferential direction. As described above, the inner sheath 6 has the partition 65. In the present embodiment, the partition portion 65 is disposed on the radially outer side surface of the 1 st sheath portion 61, and protrudes radially outward from the 1 st sheath portion 61.

The partition 65 is disposed inside the fluid passage 7. The radially outer end of the partition 65 contacts the motor housing 501, and in the present embodiment, contacts the radially inner surface of the motor cylinder 51. Thereby, the partition 65 partitions the inside of the fluid passage 7.

The rib 66 protrudes radially inward toward the radially inner side of the inner sheath 6. As described above, the inner sheath 6 has the ribs 66. In the present embodiment, the ribs 66 are disposed on the radially inner side surfaces of the pair of 2 nd sheath portions 62, and radially overlap the fluid passages 7. In this way, by the synergistic effect of the increase in the heat radiation area due to the arrangement of the ribs 66 and the thinning of the 2 nd jacket portion 62, the heat radiation efficiency from the air in contact with the ribs 66 and the 2 nd jacket portion 62 to the fluid F in the fluid passage 7 can be further improved.

The rib 66 is radially opposed to the coil head 1221. For example, the rib 66 disposed on the radially inner side surface of the 2 nd sheath portion 62 on the axial direction one D1 side is radially opposed to the coil head 1221 on the axial direction one D1 side. The rib 66 disposed on the radially inner side surface of the 2 nd sheath portion 62 on the axial other side D2 is radially opposed to the coil head 1221 on the axial other side D2.

By the arrangement of the ribs 66, the surface area of the inner sheath 6 with respect to the facing surface of the coil head 1221 (for example, the radially inner surface of the 2 nd sheath part 62) can be increased. The air around the coil head 1221 contacts the facing surface to dissipate heat. Since the heat radiation area on the facing surface can be increased, the cooling efficiency of the coil head 1221 can be improved.

The ribs 66 are provided in plural numbers and are arranged in the circumferential direction. By disposing the plurality of ribs 66, the heat dissipation area on the facing surface facing the coil head 1221 can be further increased.

Preferably, as shown in fig. 6A to 7, etc., the rib 66 extends in the axial direction. For example, compared to a structure in which the ribs 66 extend in the circumferential direction, the circulation of air between the coil head 1221 and the inner sheath 6 can be made good. Since the air in contact with the rib 66 is replaced well, the heat release efficiency from the air passing through the inner sheath 6 to the fluid F in the fluid passage 7 can be improved. This illustration does not exclude structures in which the ribs 66 do not extend axially, and in particular does not exclude structures in which the ribs 66 extend circumferentially.

< 1-5-6. Fluid passage 7 >)

Next, the fluid passage 7 will be described with reference to fig. 1,3, and 6A to 7.

A fluid passage 7 is formed radially between the motor housing 501 and the inner sheath 6. The fluid passage 7 is surrounded by the motor cylinder 51 and the inner sheath 6. The fluid passage 7 is capable of communicating the fluid F. The housing 5 also has a fluid passage 7. Preferably, the fluid passage 7 surrounds the inner sheath 6 around the rotation axis J1, and in the present embodiment, surrounds the 1 st sheath portion 61 and the 2 nd sheath portion 62.

In the present embodiment, the fluid F is water. However, the present invention is not limited to this example, and may be a liquid of an organic substance such as alcohol or oil, or may be a gas.

In the present embodiment, the fluid passage 7 is arranged between the 1 st sheath portion 61 and the 2 nd sheath portion 62 and the motor housing 501. Preferably, the interval W2 between the 2 nd sheath portion 62 and the fluid passage 7 is smaller than the interval W1 between the 1 st sheath portion 61 and the fluid passage 7 in the radial direction. In other words, the interval W1 is the thickness of the portion where the 1 st sheath portion 61 and the fluid passage 7 overlap in the radial direction. The interval W2 is the thickness of the portion where the 2 nd sheath portion 62 and the fluid passage 7 overlap in the radial direction. By forming W2 < W1, the thickness of the portion where the 2 nd sheath portion 62 and the fluid passage 7 overlap in the radial direction can be made thinner. Therefore, the heat radiation efficiency from the air passing through the 2 nd sheath portion 62 to the fluid F in the fluid passage 7 can be further improved. However, this example does not exclude the structure of W2. Gtoreq.W1.

For example, in fig. 6A, the fluid passage 7 has a spiral shape by being partitioned by a partition 65. The spiral shape extends in the axial direction D1 as it goes toward the circumferential direction. Specifically, the partition 65 disposed in the fluid passage 7 extends in a spiral shape, and extends in one axial direction D1 as it goes in one circumferential direction. By forming the fluid passage 7 in a spiral shape, the flow distance of the fluid F in the fluid passage 7 can be further increased. Therefore, for example, the cooling effect of the fluid F on the stator 12 and the like can be improved.

In fig. 6A, in a cross-sectional view of the fluid passage 7 as seen from the circumferential direction, the partition portions 65 are arranged in the axial direction. In other words, the fluid passages 7 partitioned by the partition 65 are arranged in the axial direction. The portion between the partition 65 on the most axially outward Do side of the axially aligned fluid passages 7 and the end (i.e., the 1 st inner wall 701 described later) on the axially outward Do side of the fluid passages 7 is referred to as an outermost passage 71. In addition, a portion between the axially adjacent partitions 65 is referred to as an intermediate passage 72. That is, the fluid passage 7 has an outermost passage 71 and an intermediate passage 72. The intermediate passage 72 is disposed axially inward Di of the outermost passage 71.

Preferably, the flow path cross-sectional area of the outermost passage 71 is larger than the flow path cross-sectional area of the intermediate passage 72. For example, the axial width Wo of the outermost passage 71 is larger than the axial width Wi of the intermediate passage 72. In this way, more fluid F can be caused to flow in the outermost passage 71. However, this example does not exclude a configuration in which the flow path cross-sectional area of the outermost passage 71 is equal to or smaller than the flow path cross-sectional area of the intermediate passage 72. For example, the axial width Wo of the outermost passage 71 may be equal to or smaller than the axial width Wi of the intermediate passage 72.

In addition, it is preferable that in fig. 6A, the outermost passage 71 in the fluid passage 7 overlaps with the rib 66 in the radial direction. More fluid F flows in the outermost passage 71 than in the intermediate passage 72. Therefore, the temperature of the fluid is less likely to rise than the axially inner portion. Therefore, the heat radiation efficiency from the air in contact with the rib 66 to the fluid F in the outermost passage 71 can be improved. Therefore, the cooling efficiency of the coil head 1221 can be further improved. This illustration does not preclude a structure in which the outermost passages 71 do not radially overlap the ribs 66.

On the other hand, in fig. 7, the fluid passage 7 has a serpentine shape by being partitioned by a partition portion 65. The serpentine shape meanders in the axial direction along a circumference. Specifically, the partition portion 65 disposed in the fluid passage 7 has a1 st partition portion 651 and a 2 nd partition portion 652.

The 1 st partition 651 extends from the 1 st inner wall 701 of the fluid passage 7 to the other axial direction D2, and is axially opposed to the 2 nd inner wall 702 of the fluid passage 7 with a gap therebetween. The 1 st inner wall 701 is an inner wall of the fluid passage 7 disposed on the most axial one D1 side, and faces the other axial side D2. In the present embodiment, the 1 st inner wall 701 is an end surface of the fixing portion 63 on the other axial direction D2 side. The 2 nd inner wall 702 is an inner wall of the fluid passage 7 disposed closest to the other axial direction D2 side, and faces the one axial direction D1.

The 2 nd partition 652 extends from the 2 nd inner wall 702 of the fluid passage 7 to the axial direction D1, and axially faces the 1 st inner wall 701 of the fluid passage 7 with a gap therebetween. The 1 st partition 651 and the 2 nd partition 652 are alternately arranged with a gap therebetween in the circumferential direction.

That is, the fluid passage 7 of fig. 7 is constituted by a partial passage 73, a partial passage 74, and a partial passage 75. The partial passage 73 is a portion between the tip end (i.e., the end on the axial other side D2) of the 1 st partition 651 and the 2 nd inner wall 702, and is disposed at a position closer to the axial one side D1 than the 2 nd inner wall 702 and closer to the axial other side D2 than the tip end (i.e., the end on the axial other side D2) of the 1 st partition 651. The partial passage 74 is a portion between the tip end (i.e., the end on the axial direction one D1 side) of the 2 nd partition 652 and the 1 st inner wall 701, and is disposed at a position closer to the axial direction one D1 than the tip end of the 2 nd partition 652 than the 1 st inner wall 701 is to the other axial direction one D2. The partial passage 75 is a portion of the gap between the 1 st partition 651 and the 2 nd partition 652 adjacent in the circumferential direction.

In fig. 7, by axially meandering the fluid passage 7 extending in the circumferential direction, the circulation distance of the fluid F in the fluid passage 7 can be further extended. Therefore, for example, the cooling effect of the fluid F on the stator 12 and the like can be improved.

Preferably, at least one of the partial passages 73 and 74 has a larger flow path cross-sectional area than the partial passage 75. For example, at least one of the axial width Wp1 of the partial passage 73 and the axial width Wp2 of the partial passage 74 is larger than the circumferential width Wpr of the partial passage 75. In this way, more fluid F can be flowed in at least one of the partial passages 73, 74 as the axially outer side Do side portion of the fluid passage 7 than in the partial passage 75 as the axially inner side Di side portion of the fluid passage 7. However, this example does not exclude a configuration in which the flow path cross-sectional area of both the partial passages 73, 74 is equal to or smaller than the flow path cross-sectional area of the partial passage 75. For example, both the axial widths Wp1 and Wp2 of the partial passages 73 and 74 may be equal to or smaller than the circumferential width Wpr of the partial passage 75.

In fig. 7, at least one of the partial passages 73 and 74 of the fluid passage 7 preferably overlaps the rib 66 in the radial direction. More fluid F flows in the partial passages 73, 74 than in the partial passage 75. Therefore, the heat radiation efficiency from the air in contact with the rib 66 to the fluid F in the partial passages 73, 74 can be improved. Therefore, the cooling efficiency of the coil head 1221 can be further improved. However, this example does not exclude a structure in which both of the partial passages 73, 74 do not overlap the rib 66 in the radial direction.

1-5-7 Inner bearing cage 8 >

Next, the inner bearing holder 8 will be described with reference to fig. 1 and 8. Fig. 8 is a diagram showing a configuration example of the 1 st connection portion C1 and the 2 nd connection portion C2.

The inner bearing holder 8 is attached to one end portion of the inner sheath 6 in the axial direction D1 side, and holds the 2 nd motor bearing 821. The 2 nd motor bearing 821 is disposed at a position closer to the axial direction D1 than the rotor 11, and rotatably supports a portion of the rotor shaft 110 on the axial direction D1 side. The inner bearing holder 8 is an example of the "1 st bearing holder" of the present invention. The 2 nd motor bearing 821 is an example of the "1 st bearing" of the present invention. The housing 5 also has an inner bearing cage 8. Hereinafter, the portion where the inner bearing holder 8 and the inner jacket 6 are connected is sometimes referred to as "the 2 nd connecting portion C2".

In the present embodiment, the inner bearing holder 8 is fastened to the inner sheath 6 using bolts or the like. However, the means for fixing the inner bearing holder 8 to the inner jacket 6 is not limited to this example, and the inner bearing holder 8 may be fixed by other means such as welding, brazing, or bonding.

By attaching the inner bearing holder 8 to the end portion of the inner sheath 6 on the one axial direction D1 side, the fluid passage 7 through which the fluid F can circulate can be surrounded by the inner sheath 6 and the motor housing 501. Therefore, compared with a structure in which the fluid passage 7 is further surrounded by the inner bearing holder 8, for example, leakage of the fluid F between members constituting the fluid passage 7 can be prevented.

Preferably, the 2 nd connecting portion C2 is disposed at the other axial direction D2 than the 1 st connecting portion C1 (see fig. 1). In addition, as described above, the 1 st connection portion C1 is a portion to which the motor housing 501 and the inverter housing 503 are connected. The 2 nd connecting portion C2 is a portion to which the inner sheath 6 and the inner bearing holder 8 are connected.

In this way, since the inner bearing holder 8 can be disposed at a position closer to the other axial direction D2 than the inverter case 503, the end portion of the rotor shaft 110 on the one axial direction D1 side can be disposed at a position closer to the other axial direction D2. Therefore, the axial dimension of the motor 1 can be further reduced. In addition, the inverter housing space Si connected to the motor housing space Sm can be sufficiently secured.

However, this example does not exclude a configuration in which the 2 nd connecting portion C2 is disposed at a position closer to the one axial direction D1 than the 1 st connecting portion C1, nor does it exclude a configuration in which the axial position of the 2 nd connecting portion C2 is identical to the axial position of the 1 st connecting portion C1.

As shown in fig. 8, the 1 st connecting portion C1 is preferably disposed radially outward of the 2 nd connecting portion C2 and the end portion of the inner sheath 6 on the axial direction one D1 side and fixed to the fixed portion (the fixed portion 63 in the present embodiment) of the motor housing 501. In this way, the connection between the inner sheath 6 and the inner bearing holder 8 is easily performed, and the inner sheath 6 is fixed with respect to the motor housing 501. However, this example does not exclude a configuration in which the 1 st connecting portion C1 is not disposed radially outward of the 2 nd connecting portion C2 and the above-described fixing portion. For example, the radial position of the 1 st connecting portion C1 may be the same as the radial position of at least either one of the 2 nd connecting portion C2 and the above-described fixing portion.

Further, the 1 st connecting portion C1 is preferably disposed radially outward of the motor cylinder 51. In this way, the inner sheath 6 can be easily disposed with respect to the motor cylinder 51. However, this example does not exclude a configuration in which the 1 st connecting portion C1 is not disposed radially outward of the motor cylinder 51.

The inner bearing holder 8 has a plate portion 80, an insertion hole 81, a 2 nd motor bearing holder 82, a 2 nd motor bearing 821, a 2 nd protruding wall portion 83, a1 st opening 84, and a 2 nd opening 85.

The plate portion 80 is in the form of a plate extending in a direction intersecting the rotation axis J1, and covers an end portion of the inner sheath 6 on the one axial direction D1 side.

The penetration hole 81 penetrates the plate portion 80 in the axial direction. The center of the penetration hole 81 coincides with the rotation axis J1. The motor shaft 10 (rotor shaft 110) is rotatably inserted through the insertion hole 81.

A2 nd motor bearing holder 82 for holding the 2 nd motor bearing 821 is disposed in the insertion hole 81.

The 2 nd protruding wall portion 83 protrudes toward the other axial direction D2 and extends in the circumferential direction. As described above, the inner bearing holder 8 has the 2 nd protruding wall portion 83. In the present embodiment, the 2 nd protruding wall portion 83 is annular surrounding the rotation axis J1, and protrudes from the radially outer end portion of the plate portion 80 toward the other axial direction D2.

The 2 nd protruding wall portion 83 is in contact with the 1 st protruding wall portion 64 in the radial direction. Specifically, one of the 1 st protruding wall portion 64 and the 2 nd protruding wall portion 83 is fitted to the radially inner side of the other. In the present embodiment, the 2 nd protruding wall portion 83 has a smaller outer diameter than the 1 st protruding wall portion 64, and therefore the 2 nd protruding wall portion 83 is fitted radially inward of the 1 st protruding wall portion 64.

By the fitting structure of the 1 st protruding wall portion 64 and the 2 nd protruding wall portion 83, the mounting strength of the inner bearing holder 8 to the inner sheath 6 can be improved. Further, since the positioning of the inner bearing holder 8 in the radial direction is possible, the axial center positioning of the inner bearing holder 8 can be easily performed. For example, the center of the inner bearing holder 8 as viewed in the axial direction can be aligned with the rotation axis J1.

The 1 st opening 84 and the 2 nd opening 85 penetrate the plate portion 80 in the axial direction. For example, the 1 st opening 84 and the 2 nd opening 85 are used for connecting the components arranged in the space on the radially inner side of the inner sheath 6 with the components accommodated in the inverter accommodation space Si. In this embodiment, the wiring 323 is inserted through the 1 st opening 84. Wiring 323 electrically connects the 2 nd electronic circuit 32 with the stator 12 via the 1 st opening 84. Further, a wiring 331 is inserted through the 2 nd opening 85. The wiring 331 electrically connects the electronic substrate 33 and the rotation detector 4 via the 2 nd opening 85.

The end surface of the inner bearing holder 8 on the other axial direction D2 side includes a tapered surface 86 that expands toward the other axial direction as going radially outward. The tapered surface 86 is an example of the "1 st tapered surface" of the present invention. The tapered surface 86 is disposed radially inward of the inner sheath 6. Further, the tapered surface 86 is preferably disposed radially outward of the through hole 113. In this way, the air stirred by the fan 13 on the one axial direction D1 side flows along the tapered surface 86, and is guided toward the inner sheath 6. Therefore, the heat release efficiency from the air passing through the inner sheath 6 to the fluid F in the fluid passage 7 can be further improved.

< 2 >, Others

The embodiments of the present invention have been described above. The scope of the present invention is not limited to the above-described embodiments. The present invention can be implemented by applying various modifications to the above-described embodiments within a range not departing from the gist of the invention. The matters described in the above embodiments can be appropriately and arbitrarily combined within a range where no contradiction occurs.

Industrial applicability

The present invention is useful for a driving device in which a motor and a gear portion are housed in a housing.

Description of the reference numerals

100: A driving device; 200: a battery; 300: a vehicle; 1: a motor; 10: a motor shaft; 110: a rotor shaft; 11: a rotor; 111: a rotor core; 112: a magnet; 113: a through hole; 12: a stator; 121: a stator core; 122: a coil section; 1221: a coil head; 123: an insulating member; 13: a fan; 2: a gear portion; 21: a speed reducing device; 210: a gear shaft; 211: 1 st gear; 212: a 2 nd gear; 213: a 3 rd gear; 214: an intermediate shaft; 22: a differential device; 221: a 4 th gear; 3: an inverter unit; 31: a1 st electronic circuit; 311: a capacitor; 312: a substrate; 32: a 2 nd electronic circuit; 321: a switching element; 322: a substrate; 323: wiring; 33: an electronic substrate; 331: wiring; 4: a rotation detector; 5: a housing; 501: a motor housing; 502: a gear housing; 503: an inverter housing; 51: a motor cylinder; 511: an inflow port; 512: an outflow port; 52: a1 st side plate portion; 520: a plate portion; 521: penetration holes; 522: a1 st motor bearing holder; 5221: a1 st motor bearing; 523: 1 st gear bearing cage; 5231: 1 st gear bearing; 524: 1 st intermediate bearing holder; 5241: 1 st intermediate bearing; 53: a 2 nd side plate portion; 530: a plate portion; 531: the 1 st drive shaft penetrates the hole; 532: 1 st drive bearing cage; 5321: a1 st drive bearing; 54: a gear cylinder portion; 55: a gear cover portion; 550: a cover section; 551: 2 nd gear bearing holder; 5511: a 2 nd gear bearing; 552: a 2 nd intermediate bearing holder; 5521: a 2 nd intermediate bearing; 553: the 2 nd driving shaft penetrates through the hole; 554: a 2 nd drive bearing holder; 5541: a 2 nd drive bearing; 56: an inverter cylinder; 57: an inverter cover; 6: an inner sheath; 61: a1 st sheath portion; 62: a 2 nd sheath portion; 621: a conical surface; 63: a fixing part; 64: the 1 st protruding wall part; 65: a partition portion; 651: a1 st partition; 652: a 2 nd partition; 66: a rib; 7: a fluid passage; 701: a1 st inner wall; 702: a 2 nd inner wall; 71: an outermost passageway; 72: an intermediate passage; 73. 74, 75: a partial passageway; 8: an inner bearing retainer; 80: 1 st holder plate portion; 81: penetration holes; 82: a 2 nd motor bearing holder; 821: a 2 nd motor bearing; 83: a 2 nd protruding wall portion; 84: a1 st opening; 85: a 2 nd opening; 86: a conical surface; f: a fluid; c1: a1 st connecting portion; c2: a 2 nd connecting portion; sm: a motor housing space; sg: a gear housing space; si: an inverter housing space; ds: a drive shaft; ds1: a1 st drive shaft; ds2: a 2 nd drive shaft; j1: an axis of rotation; j2: a middle axis; j3: a differential axis.

Claims (10)

1. A driving device, comprising:

a shaft extending in an axial direction along the rotation axis;

a rotor fixed to the shaft and rotatable with the shaft around the rotation axis;

a stator disposed radially outward of the rotor;

an inverter unit that supplies power to the stator; and

A housing that houses the shaft, the rotor, the stator, and the inverter unit,

The housing has:

a motor housing having a motor cylinder portion extending in an axial direction, the motor cylinder portion surrounding the rotor and the stator;

an inverter case attached to one axial end of the motor case and surrounding the inverter unit;

an inner sheath extending in an axial direction and located on a radially inner side surface of the motor cylinder;

A fluid passage surrounded by the motor cylinder and the inner sheath, the fluid passage being capable of circulating a fluid;

a1 st bearing rotatably supporting a portion of the shaft on one axial side; and

A 1 st bearing holder attached to one axial end of the inner sheath and holding the 1 st bearing,

The stator is retained on a radially inner side of the inner sheath,

One axial end of the motor housing is opened,

The interior of the inverter housing is connected to the interior of the motor housing.

2. The driving device according to claim 1, wherein,

The motor housing further has:

a 2 nd bearing rotatably supporting a portion of the shaft on the other axial side; and

And a2 nd bearing holder which expands radially inward from the other axial end of the motor cylinder to hold the 2 nd bearing.

3. The drive device according to claim 1 or 2, wherein,

The 1 st connection portion is a portion to which the motor housing and the inverter housing are connected,

The 2 nd connection portion is a portion to which the inner sheath and the 1 st bearing holder are connected,

The 2 nd connecting portion is disposed at the other axial direction than the 1 st connecting portion.

4. A driving device according to claim 3, wherein,

The 1 st connecting portion is disposed radially outward of the 2 nd connecting portion and the fixed portion of the inner sheath, the fixed portion being fixed to the motor housing at one axial end thereof.

5. The driving device according to claim 3 or 4, wherein,

The inner sheath is disposed on a radially inner side surface of the motor cylinder,

The motor cartridge and the inner sheath together form the fluid passageway,

The 1 st connection portion is disposed radially outward of the motor cylinder portion.

6. The driving device according to any one of claims 1 to 5, wherein,

The inverter unit has:

1 st electronic circuit comprising a capacitor;

a2 nd electronic circuit including a switching element; and

An electronic substrate electrically connected to the 1 st electronic circuit and the 2 nd electronic circuit,

The 1 st electronic circuit, the 2 nd electronic circuit and the electronic substrate are arranged along the axial direction.

7. The driving device according to claim 6, wherein,

The electronic substrate is disposed at a position closer to the other side than the 1 st electronic circuit and the 2 nd electronic circuit,

The 1 st electronic circuit is disposed at a position closer to one axial direction than the 2 nd electronic circuit.

8. The driving device according to any one of claims 1 to 7, wherein,

The inner sheath has a1 st protruding wall portion protruding in an axial direction at one axial end portion of the inner sheath and extending in a circumferential direction,

The 1 st bearing retainer has a2 nd protruding wall portion protruding toward the other axial direction and extending in the circumferential direction,

The 2 nd protruding wall portion is in contact with the 1 st protruding wall portion in a radial direction.

9. The driving device according to any one of claims 1 to 8, wherein,

The inner sheath has a partition protruding radially outward at a radially outer end portion of the inner sheath and extending in a circumferential direction,

The radially outer end of the partition is in contact with the motor housing,

The fluid passage has a spiral shape extending in one axial direction as it goes in one circumferential direction by being partitioned by the partition portion.

10. The driving device according to any one of claims 1 to 8, wherein,

The inner sheath has a partition protruding radially outward and extending in an axial direction at a radially outer end portion of the inner sheath,

The radially outer end of the partition is in contact with the motor housing,

The fluid passage has a shape that meanders in the axial direction while extending in the circumferential direction by being partitioned by the partition portion.