CN114930695A

CN114930695A - Motor unit

Info

Publication number: CN114930695A
Application number: CN202080092469.6A
Authority: CN
Inventors: 石川勇树; 藤原久嗣
Original assignee: Nidec Corp
Current assignee: Nidec Corp
Priority date: 2020-01-10
Filing date: 2020-12-07
Publication date: 2022-08-19
Also published as: WO2021140807A1; JPWO2021140807A1; DE112020006481T5

Abstract

The oil pump includes a housing accommodating the motor and the gear portion, and a pump for circulating oil accommodated in the housing. The housing has: a motor housing section for housing a motor; and a gear portion housing portion that is disposed on one side of the motor housing portion in the motor axis direction and houses the gear portion. The pump is attached to an outer surface of the gear portion housing portion on one side in the motor axial direction, and at least a portion of the pump overlaps the housing in the motor axial direction.

Description

Motor unit

Technical Field

The present invention relates to a motor unit.

Priority is claimed in Japanese application No. 2020 and 003243 based on 1/10/2020, and the contents of which are hereby incorporated by reference.

Background

Japanese patent laid-open No. 2016 and 73163 discloses a structure in which a refrigerant is cooled by a cooling device provided outside a rotating electrical machine, and the refrigerant is supplied to a motor by a pump provided outside the rotating electrical machine.

Documents of the prior art

Patent document

Patent document 1: international publication No. 2013/069744

Disclosure of Invention

Technical problem to be solved by the invention

However, when the pump and the cooling device are configured to be disposed outside the rotating electric machine, the rotating electric machine may become large and difficult to install.

Accordingly, an object of the present invention is to provide a motor unit capable of achieving overall miniaturization while maintaining cooling efficiency.

Technical scheme for solving technical problem

An exemplary motor unit of the present invention includes: a motor having a motor shaft that rotates centering on a motor axis extending in a horizontal direction; a gear portion connected to the motor shaft at one side in a motor axis direction along the motor axis; a housing that houses the motor and the gear portion; and a pump that circulates oil contained in the casing, the casing having: a motor housing portion that houses the motor; and a gear portion housing portion that is disposed on one side of the motor housing portion in the motor axis direction and houses the gear portion, wherein the pump is attached to an outer surface of the gear portion housing portion on one side in the motor axis direction, and at least a portion of the pump overlaps the housing in the motor axis direction.

Effects of the invention

According to the exemplary motor unit of the present invention, the entire miniaturization can be achieved while maintaining the cooling efficiency.

Drawings

Fig. 1 is a schematic view of a vehicle equipped with a motor unit according to an embodiment.

Fig. 2 is a conceptual diagram of a motor unit according to an embodiment.

Fig. 3 is a perspective view of the motor unit as viewed from above on one side in the motor axial direction.

Fig. 4 is a perspective view of the motor unit as viewed from above on the other side in the motor axis direction.

Fig. 5 is a perspective view of the motor unit as viewed from below on the other side in the motor axial direction.

Fig. 6 is a side view of the motor unit as viewed from one side in the motor axial direction.

Fig. 7 is a front view of the motor unit.

Fig. 8 is a cross-sectional view of the motor housing taken along a plane orthogonal to the motor axis.

Detailed Description

Hereinafter, a motor unit according to an embodiment of the present invention will be described with reference to the drawings. The scope of the present invention is not limited to the following embodiments, but can be arbitrarily changed within the scope of the technical idea of the present invention. Fig. 1 is a schematic view of a vehicle Cb on which a motor unit 1 according to an exemplary embodiment of the present invention is mounted. In fig. 1, the traveling direction Dd of the vehicle Cb is indicated by an arrow. The vehicle Cb is a so-called FF type vehicle in which the motor unit 1 is disposed on the front side and the front wheels Tf are driven.

In the following description, the direction of gravity is defined with reference to the positional relationship when the motor unit 1 is mounted on the vehicle Cb on a horizontal road surface. In the drawings, an XYZ coordinate system is appropriately shown as a three-dimensional rectangular coordinate system. That is, in the following description, the XYZ coordinate system is based on the state of fig. 1. In more detail, it is defined as follows.

The Z-axis direction represents a vertical direction (i.e., up-down direction), + Z-direction is an upper side (opposite to the direction of gravity), and-Z-direction is a lower side (direction of gravity). The X-axis direction is a direction orthogonal to the Z-axis direction, and indicates the front-rear direction of the vehicle Cb on which the motor unit 1 is mounted. The + X direction is the front of the vehicle Cb, and the-X direction is the rear of the vehicle Cb. However, the + X direction may be the rear of the vehicle Cb, and the-X direction may be the front of the vehicle Cb. The Y-axis direction is a direction orthogonal to both the X-axis direction and the Z-axis direction, and indicates a width direction (left-right direction) of the vehicle. The + Y direction is the left of the vehicle Cb, and the-Y direction is the right of the vehicle Cb. However, when the + X direction is the rear of the vehicle Cb, the + Y direction may be the right of the vehicle Cb, and the-Y direction may be the left of the vehicle Cb.

The driving method of the vehicle Cb is not limited to the FF method, and may be the FR method in which the motor unit 1 is disposed on the front side and the rear wheels Tr are driven. The RR system may be configured such that the motor unit 1 is disposed on the rear side of the vehicle Cb and drives the rear wheels Tr. Further, the motor unit 1 may be disposed on both the front side and the rear side, and a four-wheel drive system may be employed to drive the front wheels Tf and the rear wheels Tr. Other methods may be used. Depending on the driving method, the method of attaching the motor unit 1 to the vehicle Cb may be different. For example, the X-axis direction may be the width direction (left-right direction) of the vehicle Cb, and the Y-axis direction may be the front-rear direction of the vehicle Cb.

In the following description, unless otherwise specified, a direction (Y-axis direction) parallel to the motor axis J2 of the motor 2 is simply referred to as "axial direction", a radial direction orthogonal to the motor axis J2 is simply referred to as "radial direction", and a circumferential direction centered on the motor axis J2 is simply referred to as "circumferential direction". The "parallel direction" includes not only a completely parallel direction but also a substantially parallel direction.

The motor unit 1 is mounted in front of the vehicle Cb as a power source of driving wheels of the vehicle Cb. In the present embodiment, the vehicle Cb is an Electric Vehicle (EV), but the vehicle Cb provided with the motor unit 1 is not limited thereto, and examples thereof include a vehicle in which at least one of power sources of drive wheels is a motor, such as a Hybrid Vehicle (HV) or a plug-in hybrid vehicle (PHV).

As shown in fig. 1, the vehicle Cb drives the front wheels Tf by the motor unit 1 disposed on the front side. The output shaft 33 protrudes toward both sides of the motor unit 1 in the Y direction. An end of the output shaft 33 is connected to the motive shaft Sd via a joint Cp. The front wheel Tf is connected to the driving shaft Sd.

In the motor unit 1, the torque output from the motor 2 is output to the outside from the output shaft 33. Torque from the output shaft 33 is transmitted to the driveshaft Sd via the joint Cp. Thereby, the front wheels Tf rotate, and the vehicle Cb travels on the road surface. Examples of the joint Cp include, but are not limited to, a universal joint.

< 1. Motor Unit 1 >

Hereinafter, a motor unit 1 according to an exemplary embodiment of the present invention will be described with reference to the drawings. Fig. 2 is a conceptual diagram of the motor unit 1 of an embodiment. Fig. 3 is a perspective view of the motor unit 1 as viewed from above on one side in the direction of the motor axis J2. Fig. 4 is a perspective view of the motor unit 1 viewed from above on the other side in the direction of the motor axis J2. Fig. 5 is a perspective view of the motor unit 1 viewed from below on the other side in the direction of the motor axis J2. Fig. 6 is a side view of the motor unit 1 as viewed from one side in the direction of the motor axis J2. Fig. 7 is a front view of the motor unit 1. Fig. 8 is a cross-sectional view of the motor housing portion 51 taken along a plane orthogonal to the motor axis J2. Fig. 2 is a conceptual diagram, and the arrangement and dimensions of the respective portions may be different from those of the actual motor unit 1.

As shown in fig. 2, the motor unit 1 includes a motor 2, a gear portion 3, a pump 4, a housing 5, and an inverter unit 6. That is, the motor unit 1 includes a motor 2, a gear portion 3, and a housing 5.

< 2. Motor 2 >

As shown in fig. 2, the motor 2 includes: a rotor 21 that rotates about a motor axis J2 extending in the horizontal direction; and a stator 24, the stator 24 being located radially outside the rotor 21. The motor 2 is housed in a motor housing portion 51 described below of the housing 5.

< 2.1 rotor 21 >

The rotor 21 is rotated by supplying electric power from a battery, not shown, to the stator 24. The rotor 21 has a motor shaft 22, a rotor core 23, and a rotor magnet (not shown). The rotor 21 rotates about a motor axis J2 extending in the horizontal direction.

The motor shaft 22 extends centering on a motor axis J2 extending in the horizontal direction and the width direction of the vehicle Cb. That is, the motor 2 has a motor shaft 22 that rotates about a motor axis J2 extending in the horizontal direction. The motor shaft 22 rotates about a motor axis J2. The motor shaft 22 is a hollow shaft having a hollow portion 220 provided therein, and the hollow portion 220 has an inner peripheral surface extending along the motor axis J2.

The motor shaft 22 extends across the motor housing 51 and the gear housing 52 of the housing 5. One end (+ Y side) of the motor shaft 22 protrudes into the gear portion housing portion 52. A first gear 311 of the gear portion 3 described below is fixed to an end portion of the motor shaft 22 protruding into the gear portion housing 52. The motor shaft 22 is rotatably supported by a first motor bearing 281, described below, disposed on the bottom portion 512 and a second motor bearing 282 disposed on the partition wall portion 513 of the housing 5.

The portion of the motor shaft 22 disposed in the gear portion housing portion 52 is rotatably supported by the second motor bearing 282 and the first gear bearing 341. As described above, the second motor bearing 282 is disposed on the partition wall 513. The first gear bearing 341 is disposed in the below-described gear housing portion 52 of the housing 5. The motor shaft 22 may be divided into a portion in the motor housing 51 and a portion in the gear housing 52. In the case where the motor shaft 22 is dividable, for example, a screw coupling structure using a male screw and a female screw may be employed for the divided motor shaft 22. Further, the joining may be performed by a fixing method such as welding.

The rotor core 23 is formed by laminating silicon steel plates. The rotor core 23 is a cylindrical body extending in the axial direction. A plurality of rotor magnets are fixed to the rotor core 23. The plurality of rotor magnets are arranged along the circumferential direction in such a manner that magnetic poles are alternated.

< 2.2 stator 24 >

The stator 24 surrounds the rotor 21 from the radially outer side. That is, the motor 2 is an inner rotor type motor in which the rotor 21 is rotatably disposed inside the stator 24. The stator 24 includes a stator core 25, a coil 26, and an insulator (not shown) interposed between the stator core 25 and the coil 26. The stator 24 is held by the housing 5. The stator core 25 has a plurality of magnetic pole teeth from the inner circumferential surface of the annular yoke to the radially inner side.

The coil 26 is formed by winding a wire between the magnetic pole teeth. The lead wires are connected to the inverter unit 6 via bus bars, not shown.

< 3. Gear part 3 >

The gear portion 3 transmits torque output from the motor 2 to a motive shaft Sd connected to the front wheels Tf. As shown in fig. 2, the gear portion 3 is accommodated in the gear portion accommodating portion 52 of the housing 5. The gear portion 3 is connected to the motor shaft 22 at one axial side (+ Y direction side). That is, the gear portion 3 is connected to the motor shaft 22 on the motor axial direction side (+ Y direction side) along the motor axis J2. The gear portion 3 has a speed reduction portion 31 and a differential portion 32.

< 3.1 the speed reducing part 31 >

As shown in fig. 2 and 5, the speed reducer 31 is connected to the motor shaft 22. The speed reducer 31 has a function of reducing the rotation speed of the motor 2 and increasing the torque output from the motor 2 according to the speed reduction ratio. The speed reducer 31 transmits the torque output from the motor 2 to the differential portion 32.

The speed reducer 31 is a parallel-axis gear type speed reducer in which the axes of the gears are arranged in parallel. The speed reducer 31 includes: a first gear 311 as an intermediate driving gear; a second gear 312 as an intermediate gear; a third gear 313 as a final drive gear; and an intermediate shaft 314.

The first gear 311 is disposed on the outer peripheral surface of the motor shaft 22. The first gear 311 may be the same member as the motor shaft 22 or may be a separate member and firmly fixed. The first gear 311 rotates together with the motor shaft 22 about the motor axis J2.

The intermediate shaft 314 extends along an intermediate axis J4 that is parallel to the motor axis J2. Both ends of the intermediate shaft 314 are rotatably supported by a second gear bearing 342 disposed on the partition wall portion 513 and a third gear bearing 343 disposed on a cover bottom portion 525 described below of the gear portion cover portion 522.

The intermediate shaft 314 is supported by the housing 5 to be rotatable about an intermediate axis J4. The second gear 312 and the third gear 313 are disposed on the outer peripheral surface of the intermediate shaft 314. That is, the second gear 312 and the third gear 313 are connected by an intermediate shaft 314. The second gear 312 may be the same member as the intermediate shaft 314 or may be a different member and firmly fixed. The third gear 313 is also similar to the second gear 312.

The second gear 312 and the third gear 313 rotate about the intermediate axis J4. The second gear 312 is engaged with the first gear 311. The third gear 313 meshes with the ring gear 321 of the differential portion 32.

The torque of the motor shaft 22 is transmitted from the first gear 311 to the second gear 312. The torque transmitted to the second gear 312 is transmitted to the third gear 313 via the intermediate shaft 314. The torque transmitted to the third gear 313 is transmitted to the ring gear 321 of the differential portion 32. Thus, the speed reducer 31 transmits the torque output from the motor 2 to the differential unit 32. The gear ratio of each gear, the number of gears, and the like can be variously changed according to a required reduction ratio.

< 3.3 differential part 32 >, and

the differential portion 32 transmits the torque output from the motor 2 to the output shaft 33. The output shafts 33 are attached to the left and right of the differential portion 32, respectively. As shown in fig. 1, the output shaft 33 is connected to the driveshaft Sd via a joint Cp.

The differential section 32 has the following functions: for example, when the vehicle Cb turns, the speed difference between the left and right front wheels Tf, that is, the output shaft 33 is absorbed, and the same torque is transmitted to the left and right output shafts 33. The differential portion 32 includes a ring gear 321, a gear housing (not shown), a pair of pinion gears (not shown), a pinion shaft (not shown), and a pair of side gears (not shown).

As shown in fig. 5, 7, and the like, the end of the output shaft 33 on the other axial side (the Y direction side) protrudes further than the end of the motor housing portion 51 of the housing 5 on the other axial side (the Y direction side).

In the gear portion 3 of the present embodiment, the output shaft 33 projects to both sides in the Y direction, but the present invention is not limited to this. For example, according to the method of mounting the motor unit 1, the output shaft 33 may be projected only in one direction of the Y direction, and the single wheels may be driven by the pair of motor units 1. In this case, the differential portion may be omitted.

< 3.3 parking mechanism >

For example, in an electric vehicle, there is no braking mechanism that applies a brake to the vehicle Cb other than the side brake. Therefore, a parking mechanism for locking the vehicle Cb when a shift lever (not shown) is moved to a parking position may be attached to the motor unit 1. In the case where the vehicle Cb is HV, PHV, or the like, having an internal combustion engine and a transmission, the parking mechanism may be omitted.

< 4. inverter Unit 6 >

The inverter unit 6 is electrically connected to the stator 2. The inverter unit 6 controls the power supplied to the motor 2. As shown in fig. 2, the inverter unit 6 is housed in an inverter housing portion 53 of the housing 5. The housing 5 further has an inverter housing portion 53, and the inverter housing portion 53 houses the inverter unit 6 that supplies electric power to the motor 2.

As shown in fig. 2, the refrigerant is supplied to the inverter unit 6 from a radiator, not shown. As shown in fig. 2, an inverter cooling passage 71 for flowing a refrigerant is disposed in a housing cover 531 for closing an opening of the inverter housing portion 53. The refrigerant from the radiator flows into the inverter cooling passage 71 through the refrigerant pipe 72. The refrigerant passes through the inverter cooling passage 71, whereby heat generated by the inverter unit 6 is transferred to the refrigerant. That is, the inverter unit 6 is cooled.

< 5. Pump 4 >

The pump 4 circulates the oil CL in the inner space of the casing 5. That is, the pump 4 circulates the oil CL contained in the casing 5. The oil CL circulated by the pump 4 is supplied to the motor 2. Motor 2 is cooled by oil CL. The pump 4 is an electric pump.

As shown in fig. 3, 7, and the like, the pump 4 is attached to the outer surface of the gear portion housing portion 52 of the housing 5 on one axial side (+ Y direction side) of the below-described cover flange portion 526. The pump 4 circulates oil CL for cooling the motor 2 and the gear portion 3 inside the casing 5.

The pump 4 includes a pump motor and a compression unit, both of which are not shown. The compression section has a suction port and a discharge port. The compression unit includes, for example, a trochoid pump in which an external gear and an internal gear are meshed with each other and rotate, which is not illustrated, but is not limited thereto. For example, the compression unit may be a pump other than a trochoid pump such as a centrifugal pump. The pump motor drives the compression section. The compression unit is driven by the pump motor, and sucks the oil CL in the oil reservoir 54 from the suction port, compresses the oil, and discharges the compressed oil from the discharge port.

As shown in fig. 7, the suction port of the pump 4 is connected to the oil reservoir 54 via a suction pipe 500. The suction pipe 500 has a pipe shape disposed inside the casing 5. One end of the suction pipe 500 is connected to the oil reservoir 54. The oil CL stored in the oil reservoir 54 is sucked from the suction pipe 500 by driving the pump 4. The oil CL sucked from the suction pipe 500 is sucked into the pump 4 from the suction port of the pump 4. That is, the suction port of the pump 4 for sucking oil is connected to the suction pipe 500, and the suction pipe 500 is connected to the internal space of the oil reservoir 54. The suction pipe 500 may be formed in a pipe shape formed inside the housing 5, or may be formed by a separately prepared pipe.

The discharge port of the pump 4 is connected to a flow pipe portion 561 described below of the oil pipe portion 56. The oil CL discharged from the discharge port of the pump 4 flows into the oil cooler 8 via the flow pipe portion 561.

With the above configuration, the oil CL can be circulated inside the motor housing space 501.

< 6. oil cooler 8 >

The oil CL and the refrigerant supplied through a different path from the oil CL are supplied to the oil cooler 8. The oil cooler 8 has an oil flow pipe portion and a refrigerant flow pipe portion, both of which are not shown. The oil flow pipe portion and the refrigerant flow pipe portion are separated by a high thermal conductivity material such as aluminum or copper, and heat is exchanged between the oil and the refrigerant.

One end of the oil flow pipe portion of the oil cooler 8 is connected to the discharge port of the pump 4 via a flow pipe portion 561 of the oil pipe portion 56. Thereby, the oil CL discharged from the discharge port of the pump 4 flows into the oil flow pipe portion of the oil cooler 8 via the flow pipe portion 561. The other end of the oil flow pipe portion of the oil cooler 8 is connected to a supply pipe portion 562 of the oil pipe portion 56, which will be described later. The cooled oil CL flowing out of the oil cooler 8 is sent to the oil spreading portion 57 described below via the supply pipe portion 562. That is, the oil cooler 8 that cools the oil CL passing through the oil pipe portion 56 is disposed in the path of the oil pipe portion 56.

As described above, the refrigerant that exchanges heat with the oil CL flows into the refrigerant flow tube portion of the oil cooler 8. Here, a description will be given of a pipe for a refrigerant through which the refrigerant flows. In the motor unit 1 of the present embodiment, the refrigerant that has exchanged heat with the oil CL by the oil cooler 8 flows into the oil cooler 8 after being used to cool the inverter unit 6.

The inverter cooling passage 71 and the oil cooler 8 are connected via a connection pipe 73. The refrigerant flowing out of the inverter cooling passage 71 flows into the refrigerant flow tube portion of the oil cooler 8 via the connection pipe 73. The oil CL flows in the oil flow tube portion, and the refrigerant flows in the refrigerant flow tube portion. At this time, the heat of oil CL is transferred to the refrigerant, and oil CL is cooled.

The outflow portion of the refrigerant flow tube portion of the oil cooler 8 is connected to the radiator via a return pipe 74. The refrigerant that has exchanged heat with the oil CL in the oil cooler 8 passes through the return pipe 74 and returns to the radiator. The refrigerant is cooled by radiating heat to the outside through the radiator. In the present embodiment, the oil CL is cooled by the refrigerant that cools the inverter unit 6, but the present invention is not limited to this. For example, a pipe may be provided to receive the refrigerant directly from the radiator and return the refrigerant.

< 7. housing 5 >

As shown in fig. 2 and the like, the housing 5 includes a motor housing portion 51, a gear portion housing portion 52, an inverter housing portion 53, an oil reservoir portion 54 (see fig. 4 and 5), an output shaft support portion 55, an oil pipe portion 56 (see fig. 7), an oil spreading portion 57 (see fig. 8), and ribs 58 (see fig. 5).

The gear portion housing portion 52 is located on one axial side (+ Y direction side) of the motor housing portion 51. The motor housing 51 and the gear portion housing 52 are made of, for example, a metal such as iron, aluminum, or an alloy of iron and aluminum, but are not limited thereto.

As shown in fig. 2, the housing 5 has a motor housing space 501 and a gear portion housing space 502. The motor housing space 501 is a space inside the motor housing portion 51. The motor 2 is accommodated in the motor accommodating space 501. The gear portion accommodating space 502 is a space inside the gear portion accommodating portion 52. The gear portion housing space 502 houses the gear portion 3. That is, the housing 5 accommodates the motor 2 and the gear portion 3.

< 7.1 Motor housing part 51 >

The motor housing portion 51 has a cylindrical portion 511 and a bottom portion 512. The cylindrical portion 511 is open on one axial side (+ Y direction side) and extends in the axial direction. The bottom portion 512 extends radially inward from the end portion on the other axial side (the Y direction side) of the cylindrical portion 511. The bottom 512 closes the other axial end (the Y-direction side) of the cylindrical portion 511. In the motor housing portion 51, the cylindrical portion 511 and the bottom portion 512 are formed of the same member. Thus, the motor housing portion 51 has a bottomed cylindrical shape.

The motor housing portion 51 has a bottomed cylindrical shape with the gear portion housing portion 52 open on the side, and thus the motor unit 1 can be assembled only by performing work from one axial side (+ Y direction side). Therefore, it is not necessary to change the position of the operator or the position of the housing 5, and the number of working steps can be reduced. Therefore, the cost required for the work can be reduced.

< 7.2 oil reservoir 54 >

An oil reservoir 54 protruding radially outward is disposed below (on the side of the Z direction) the motor reservoir 51. The motor housing portion 51 and the oil reservoir portion 54 are formed by the same member, and the circumferential wall of the oil reservoir portion 54 continuously protrudes outward in the radial direction from the circumferential wall of the motor housing portion 51. The oil reservoir 54 extends in the axial direction and is connected to a motor housing space 501 of the motor housing portion 51 (see fig. 8). The oil CL in the motor housing space 501 flows downward and is stored in the oil reservoir 54. That is, the housing 5 further includes an oil reservoir portion that swells from a lower portion of the motor reservoir portion 51 in the vertical direction outward in the radial direction of the motor reservoir portion 51 and that stores the oil CL.

In the present embodiment, the motor housing portion 51 and the oil reservoir portion 54 are formed by the same member, but the present invention is not limited thereto. For example, a slit extending in the axial direction (Y direction) may be formed below the motor housing portion 51, and the slit may be covered with an oil reservoir portion 54 separately prepared. The oil reservoir 54 is formed in an arc shape having a smaller radius of curvature than the motor housing portion 51, but the invention is not limited thereto. For example, the shape may be a combination of planes. The shape that can store the oil that circulates in the motor storage portion 51 and flows downward can be widely used.

As shown in fig. 8, cooling

pipe portions

541 and 542 that are disposed adjacent to the oil reservoir portion 54 and through which the refrigerant flows may be provided. That is, the housing 5 further includes cooling

pipe portions

541 and 542 through which the refrigerant flows, and the

cooling pipe portions

541 and 542 through which the refrigerant that cools the oil CL stored in the oil storage portion 54 flows.

The cooling pipe portion 541 is formed inside the wall portion of the oil reservoir portion 54, and has a pipe shape extending in the axial direction (Y direction). The inner side of the oil reservoir 54 of the cooling pipe portion 541 protrudes inward. This increases the area of the inner surface in contact with the oil CL, thereby improving the heat exchange efficiency, i.e., the cooling efficiency.

The cooling pipe portion 542 is a cylindrical body disposed inside the oil reservoir portion 54. By using the cooling pipe portion 542, the oil CL stored in the oil reservoir portion 54 can be efficiently cooled. Further, the cooling pipe portion 542 is disposed inside the housing 5, but is disposed in the space inside the oil reservoir portion 54, and therefore the motor 2 is not easily obstructed. In the housing 5 shown in fig. 8, both the cooling pipe portion 541 and the cooling pipe portion 542 are used, but either one may be used.

The coolant supplied to the

cooling pipe portions

541 and 542 may be, for example, a coolant that cools other components such as the inverter unit 6, or may be directly supplied from a radiator. The oil CL stored in the oil storage 54 may be heated at the time of cold start. This makes it possible to set the oil to an appropriate viscosity immediately after the cold start. This enables lubrication of the motor 2 and the gear portion 3 immediately after cold start, thereby prolonging the life of the motor unit 1.

< 7.3 partition wall 513 >

The cylindrical portion 511 and the oil reservoir 54 are open on one axial side (+ Y direction side). The partition wall 513 closes the openings of the cylindrical portion 511 and the oil reservoir 54. Partition wall 513 is attachable to and detachable from motor storage portion 51 and oil reservoir portion 54.

The motor 2 is accommodated in a motor accommodating space 501 surrounded by the cylindrical portion 511, the bottom portion 512, and the partition wall portion 513. A first motor bearing 281 is disposed at the bottom 512. The end portion on the other axial side (the Y direction side) of the motor shaft 22 is rotatably supported by a first motor bearing 281.

The partition wall 513 has a through hole 514 formed therein. The through hole 514 penetrates the partition wall 513 in the axial direction. The center of the through hole 514 coincides with the motor axis J2. The second motor bearing 282 is disposed in the through hole 514. The motor shaft 22 penetrates the through hole 514. At this time, the Y-direction intermediate portion of the motor shaft 22 is rotatably supported by the second motor bearing 282. That is, the motor shaft 22 is rotatably supported by the through hole 514 via the second motor bearing 282.

The second gear bearing 342 is disposed below (in the-Z direction) the through hole 514 on one axial side (+ Y direction side) of the partition wall 513. The second gear bearing 342 rotatably supports the other axial end portion (-Y direction side) of the intermediate shaft 314.

An oil flow hole 515 is formed at the partition wall portion 513. The oil flow hole 515 is a through hole that penetrates the partition wall 513 in the axial direction. The oil flow hole 515 connects the oil reservoir 54 and the gear portion receiving portion 52. Part of the oil CL stored in the oil reservoir 54 flows into the gear portion accommodating space 502 of the gear portion accommodating portion 52 through the oil flow hole 515. Further, by forming the oil flow hole 515 at a position having a constant height from the bottom of the oil reservoir 54, the oil CL can be left in the oil reservoir 54.

< 7.4 gear part housing part 52 >

The gear portion housing 52 houses the gear portion 3. That is, the housing 5 has a gear portion housing portion 52 that houses the gear portion 3. The gear portion housing portion 52 is disposed on one axial side (+ Y direction side) of the motor housing portion 51. That is, the housing 5 has a gear portion housing portion 52 that is disposed on one axial side (+ Y direction side) of the motor housing portion 51 and houses the gear portion 3.

The gear portion housing portion 52 includes a gear portion support portion 521 and a gear portion cover portion 522. The gear portion supporting portion 521 extends radially outward from the outer surface of the end portion on one axial side (+ Y direction side) of the cylindrical portion 511 of the motor housing portion 51. The gear portion supporting portion 521 is formed of the same member as the cylindrical portion 511. That is, the gear portion housing portion 52 has a gear portion supporting portion 521 that extends radially outward from the outer surface of the end portion on one axial side (+ Y direction side) of the motor housing portion 511.

The gear portion supporting portion 521 is formed with a first output shaft passage hole 523. The output shaft 33 passes through the first output shaft passage hole 523. Thus, the output shaft 33 passes through the gear portion support portion 521 and extends to the other axial side (the Y direction side). The output shaft 33 is aligned with the motor housing 51. That is, the gear portion 3 has the output shaft 33 that penetrates the gear portion support portion 521 and extends to the other axial side (the Y-direction side).

The other axial end portion (-Y direction side) of the output shaft 33 is rotatably supported by the output shaft support portion 55. In addition, details of the output shaft support portion 55 will be described later. An oil seal (not shown) is provided between the output shaft 33 and the first output shaft passage hole 523 to suppress leakage of the oil CL.

The gear portion cover portion 522 includes a cover cylinder portion 524, a cover bottom portion 525, and a cover flange portion 526. The cover cylinder portion 524 is cylindrical with the other axial side (the Y-direction side) open. The cover bottom portion 525 extends radially inward from an end portion on one axial side (+ Y direction side) of the cover cylindrical portion 524. The cover cylinder portion 524, the cover bottom portion 525, and the cover flange portion 526 are formed of the same member. That is, the gear portion cover portion 522 has a bottomed cylindrical shape, and is open on the other axial side (the Y direction side).

The cover flange portion 526 protrudes radially outward from the other axial side (-Y direction side) of the cover cylindrical portion 524. The cover flange portion 526 overlaps the gear portion supporting portion 521 as viewed in the axial direction. The gear portion supporting portion 521 and the cover flange portion 526 are axially overlapped. The edge portion of the cover flange portion 526 is fixed to the edge of the gear portion supporting portion 521, whereby the gear portion cover portion 522 is attached to the gear portion supporting portion 521.

The first gear bearing 341 and the third gear bearing 343 are mounted to the cover bottom 525. An end portion on one axial side (+ Y direction side) of the motor shaft 22 is rotatably supported by the first gear bearing 341. Further, an end portion on one axial side (+ Y direction side) of the intermediate shaft 314 is rotatably supported by a third gear bearing 343. That is, the motor shaft 22 is rotatably supported by the housing 5 via the first motor bearing 281, the second motor bearing 282, and the first gear bearing 341. Further, the intermediate shaft 314 is rotatably supported by the housing 5 via a second gear bearing 342 and a third gear bearing 343.

Further, a second output shaft passing hole 527 is formed at the cover cylinder portion 524. The output shaft 33 passes through the second output shaft passing hole 527. Thus, the output shaft 33 penetrates the cover cylindrical portion 524 and extends to one axial side (+ Y direction side). An oil seal (not shown) is provided between the output shaft 33 and the second output shaft passage hole 527 in order to suppress leakage of the oil CL.

In the gear portion housing portion 52, the first output shaft passage hole 523 and the second output shaft passage hole 527 overlap when viewed in the axial direction. Further, the first output shaft passage hole 523 is penetrated by a portion of the output shaft 33 on the other axial side (-Y direction side) than the differential portion 32, and the second output shaft passage hole 527 is penetrated by a portion on one axial side (+ Y direction side). The output shaft 33 disposed at both ends of the differential portion 32 in the axial direction (Y direction) rotates about an output axis J5.

< 7.5 inverter housing part 53 >

As shown in fig. 3, 4, 8, and the like, the inverter housing portion 53 is disposed above the motor housing portion 51 and on the-X direction side. The inverter housing portion 53 and the motor housing portion 51 are formed of the same member. That is, the inverter housing portion and the motor housing portion 51 are formed of the same member. The inverter housing portion 53 is open at the upper side. A housing cover 531 is attached to an opening of the inverter housing 53. The inverter unit 6 is housed in a space surrounded by the inverter housing portion 53 and the housing cover portion 531.

The housing cover 531 is fixed to the inverter housing portion 53 by a fixing method such as screwing. Thereby, the opening of the inverter housing portion 53 is closed by the housing cover portion 531. The fixing of the housing cover 531 to the inverter housing portion 53 is not limited to screw fastening, and a fixing method that can be firmly fixed and can be attached and detached is widely used.

The abutting portion between the inverter housing portion 53 and the housing cover portion 531 has a structure that suppresses the intrusion of moisture. This makes it difficult for water to adhere to the inverter unit 6 housed in the inverter housing portion 53. Further, as the structure for suppressing the intrusion of moisture at the abutting portion between the inverter housing portion 53 and the housing cover portion 531, for example, a structure in which a gasket, a packing, or the like is disposed between the inverter housing portion 53 and the housing cover portion 531 is exemplified, but not limited thereto.

The internal space of the inverter housing portion 53 is connected to the motor housing space 501 of the motor housing portion 51 through the wiring hole 532. The wiring connecting the inverter unit 6 and the coil 26 of the motor 2 is disposed in the wiring hole 532. By providing the wiring hole 532, the opening through which the supply water is branched into the internal space of the inverter housing portion 53 can be reduced. Further, a seal (not shown) for suppressing entry of the oil CL circulating in the motor housing space 501 is provided in the wiring hole 532.

As shown in fig. 3, 4, 5, 8, and the like, the housing cover 531 has an inverter cooling passage 71. The refrigerant passes through the inside of the inverter cooling passage 71. When the refrigerant passes through the inverter cooling passage 71, heat generated by the inverter unit 6 is transferred to the refrigerant. Thereby, the inverter unit 6 is cooled. The inverter unit 6 is cooled, and therefore can operate stably. In the housing 5 of the present embodiment, the inverter cooling passage 71 is disposed in the housing cover 531. In order to improve the cooling efficiency, the inverter unit 6 may be attached to the housing cover 531. The inverter cooling passage 71 may be disposed in the inverter housing portion 53. In this case, the inverter unit 6 may be mounted in the inverter housing portion 53.

< 7.6 output shaft support portion 55 >

The output shaft support portion 55 protrudes to the outside of the end portion on the other axial side (the Y direction side) of the outer peripheral surface of the motor housing portion 51. The output shaft support portion 55 is formed of the same member as the motor housing portion 51.

The output shaft support portion 55 has a through hole whose center coincides with the output axis J5, and an output bearing 551 (see fig. 2, 4, and 5) is attached to the through hole. The output shaft support portion 55 rotatably supports the output shaft 33 via an output bearing 551.

That is, the housing 5 further includes an output shaft support portion 55 that rotatably supports the output shaft 33 on the other side (the Y direction side) in the axial direction of the motor housing portion 51. (0747, claim 1, and lines 13 to 14) the output shaft support portion 55 and the motor housing portion 51 are formed of the same member.

The output shaft support portion 55 is formed of the same member as the lower surface of the inverter housing portion 53. The output shaft support portion 55 is formed by integral molding together with the inverter housing portion 53. With such a configuration, the rigidity of the output shaft support portion 55 can be increased, and vibration of the output shaft 33 can be suppressed.

The output shaft support portion 55 and the inverter housing portion 53 may be formed of different members. At this time, the output shaft support portion 55 may contact the inverter housing portion 53. When the output shaft support portion 55 and the inverter housing portion 53 are not formed of the same member, stress is not easily transmitted from the inverter housing portion 53 to the output shaft support portion 55. Therefore, even when stress acts on the inverter housing portion 53, deformation of the output shaft support portion 55 is suppressed, and the center runout of the output shaft 33 is less likely to occur.

The output shaft support portion 55 and the inverter housing portion 53 may be in non-contact. Stress is not easily transmitted between the inverter housing portion 53 and the output shaft support portion 55, and vibration and the like can be suppressed. The output shaft support portion 55 and the inverter housing portion 53 may be formed by the same member, and the output shaft support portion 55 and the motor housing portion 51 may be formed by different members. By forming as described above, resonance of vibration of the motor 2 transmitted to the motor housing portion 51 and vibration transmitted to the output shaft support portion 55 can be suppressed.

Since the housing 5 has the output shaft support portion 55, the output shaft 33 can be extended from the gear portion support portion 521 toward the other axial side (the Y direction side). As shown in fig. 1, the driveshaft Sd is connected to the distal end portion of the output shaft 33 via a joint Cp (see fig. 1).

By adjusting the length of the output shaft 33, the lengths of the main drive shafts Sd connected to the left and right front wheels Tf when the motor unit 1 is mounted on the vehicle Cb can be made the same. By making the lengths of the axle shafts Sd the same, the axle shafts Sd are connected at the same angle with respect to the output shaft 33. Thereby, an equal torque is transmitted to the left and right front wheels Tf, and the driver can operate the vehicle Cb without a sense of incongruity. That is, the operability of the vehicle Cb can be improved.

In the motor unit 1, the length of the output shaft 33, which makes the left and right main shafts Sd equal in length, is determined in the gear portion 3 based on the position of the motor unit 1 mounted on the vehicle Cb and the position of the front wheels Tf. Further, since the housing 5 has the output shaft support portion 55, the output shaft 33 can stably rotate even if the output shaft 33 is extended toward the other side (the Y direction side) in the axial direction.

In other words, since the housing 5 of the motor unit 1 has the output shaft support portion 55, the output shaft 33 can be extended toward the other side (the (-Y direction side) in the axial direction. This makes it possible to make the left and right motive shafts Sd of the vehicle Cb on which the motor unit 1 is mounted equal in length, and to suppress the sense of discomfort felt by the driver while driving. The output shaft support portion 55 preferably supports the vicinity of the end of the output shaft 33.

In the motor unit 1 of the present embodiment, both ends of the output shaft 33 in the Y direction protrude outward from the housing 5. Therefore, when the motive axis Sd is installed via the joint Cp, the joint Cp and the motive axis Sd are less likely to interfere with the housing 5.

As shown in fig. 5, the rib 58 protrudes from the outer surface of the cylindrical portion 511 of the motor housing portion 51 in the radial direction and extends radially outward in the axial direction, and connects the gear portion support portion 521 to the output shaft support portion 55. That is, the housing 5 further has a plate-shaped rib 58 that protrudes from the outer surface in the radial direction of the motor housing portion 51 and connects the gear portion supporting portion 521 and the output shaft supporting portion 55.

The rib 58 is formed of the same member as the motor housing portion 51. The rib 58 is formed of the same member as the gear portion supporting portion 521 and the output shaft supporting portion 55. That is, the rib 58 is formed by the same member as the motor accommodating portion 51, the gear portion supporting portion 521, and the output shaft supporting portion 55. By providing the rib 58, deformation of the motor housing portion 51, the gear portion supporting portion 521, and the output shaft supporting portion 55 is suppressed. This suppresses vibration and noise of the motor 2 and the gear portion 3 caused by driving thereof and the housing 5.

In the present embodiment, the rib 58 has a width protruding from the cylindrical portion 511 that decreases from the gear portion supporting portion 521 side toward the output shaft supporting portion 55 side. The shape is not limited to the above shape, and a shape capable of suppressing vibration and noise by the rib 58 can be widely used.

< 7.7 oil piping part 56 >

As shown in fig. 2 and 6, the oil pipe portion 56 has a tubular shape formed inside the gear portion supporting portion 521 of the gear portion housing portion 52. The oil pipe portion 56 is connected to an oil distributing portion 57 provided in an upper portion of the motor housing space 501. The oil piping portion 56 connects the pump 4 to the oil scattering portion 57, and supplies the oil CL to the oil scattering portion 57. That is, the housing 5 has an oil pipe portion 56 that connects a discharge port of the pump 4 for discharging oil and an oil distribution portion 57 provided in the internal space 501 of the motor housing portion 51.

The housing 5 of the present embodiment includes a flow pipe portion 561 and a supply pipe portion 562. The flow piping portion 561 connects a discharge port of the pump 4 to an inflow port of the oil cooler 8. That is, the oil CL pressurized by the pump 4 is sent from the pump 4 to the oil cooler 8 via the flow pipe portion 561. The supply pipe portion 562 connects the outflow portion of the oil cooler 8 to the below-described flow path 571 of the oil scattering portion 57. That is, the oil CL cooled by the oil cooler 8 is sent from the oil cooler 8 to the oil distribution portion 57 via the supply pipe portion 562.

In the present embodiment, the oil pipe portion 56 is formed in the cover flange portion 526, but is not limited thereto. The gear portion supporting portion 521 may be formed, or the gear portion supporting portion 521 and the cover flange portion 526 may be combined and fixed.

< 7.8 oil spreading portion 57 >

Oil scattering portion 57 is disposed in motor storage portion 51. The oil scattering portion 57 is disposed above the motor 2 in the vertical direction. That is, the housing 5 further includes an oil distribution portion 57 disposed vertically above the motor 2 in the motor housing portion 51 and connected to the oil pipe portion 56.

The oil spreading portion 57 has: a flow passage 571 that extends in the axial direction (Y direction) and through which the oil CL flows; and a distribution hole 572 connecting the flow path 571 with the motor housing space 501.

The oil CL flowing through the oil pipe portion 56 flows into the flow passage 571 of the oil spreading portion 57. The oil CL flowing into the flow path 571 is dispersed from the dispersion hole 572 into the motor housing space 501. With the above configuration, the oil CL can be distributed to the motor 2 disposed in the motor housing space 501. This enables the motor 2 to be efficiently cooled by the oil CL. In the present embodiment, the oil scattering portion is formed in a tubular shape formed inside the motor housing portion 51, but the present invention is not limited thereto. For example, a pipe inserted into the motor housing space 501 may be used.

Instead of the tubular shape, the oil scattering portion 57 may be in the form of a container having an upper opening and an oil dropping hole at an appropriate position of the bottom. At this time, the oil CL supplied from the supply pipe part 562 flows into the oil scattering part 57, and the oil is dropped from the oil scattering part 57.

< 7.9 position of pump 4 and oil cooler 8 >

The pump 4 and the oil cooler 8 are attached to one axial side (+ Y direction side) of the cover flange portion 526 of the gear portion housing portion 52 of the housing 5. Further, the pump 4 and the oil cooler 8 are attached to the outside of the gear portion housing portion 52. The oil piping portion 56 connects the pump 4 and the oil cooler 8. The oil piping portion 56 connects the oil cooler 8 and the oil distribution portion 57.

As shown in fig. 6, the pump 4 and the oil cooler 8 are disposed at positions falling within the axial projection plane of the housing 5. Further, a part of the pump 4 and the oil cooler 8 may protrude outward from the axial projection surface of the housing 5. That is, the pump 4 is attached to the outer surface of the gear portion housing portion 52 on one axial side (+ Y direction side) and at least partially overlaps the housing 5 in the axial direction. The oil cooler 8 is attached to the outer surface of the gear portion housing 52 on one side in the axial direction (+ Y direction side), and at least a part thereof overlaps the housing 5 in the axial direction.

With the above configuration, the thickness of the motor unit 1 in the vertical direction (Z direction) can be reduced. The motor unit 1 can be miniaturized. The pump 4 is exposed to the outside of the motor unit 1. When the vehicle is running, the running wind collides with the pump 4. The pump 4 is cooled by traveling wind when the vehicle is traveling. Further, traveling wind during traveling of the vehicle also collides with the outer surface of the oil cooler 8. Thereby, the oil cooler 8 is cooled by the traveling wind.

< 8 lubrication and Cooling of Motor Unit 1 >

As shown in fig. 2, an oil reservoir P in which the oil supply CL is stored is provided in a lower region in the gear portion housing portion 52. A part of the differential portion 32 is immersed in the oil reservoir P. The oil CL accumulated in the oil reservoir P is lifted by the operation of the differential portion 32, and is supplied to the inside of the gear portion housing portion 52. That is, the oil CL is raised by the tooth surface of the ring gear 321 when the ring gear 321 of the differential portion 32 rotates.

The oil CL diffused into the gear portion housing 52 is supplied to the respective gears of the speed reduction portion 31 and the differential portion 32 in the gear portion housing 52, and the oil CL spreads over the tooth surfaces of the gears for lubrication. Further, a part of the oil CL diffused to the gear part housing 52 is supplied to each of the second motor bearing 282, the first gear bearing 341, the second gear bearing 342, and the third gear bearing 343 for lubrication.

During operation from a state in which the motor 2 is stopped, a part of the ring gear 321 is immersed in the oil CL. Therefore, the oil CL is lifted upward along the inner peripheral surface of the gear portion accommodating space 502 by the rotation of the ring gear 321.

A reservoir 528 is disposed in the gear portion housing space 502. The reservoir 528 is open upward. Further, the reservoir 528 is formed across both axial ends of the gear portion housing space 502. The oil CL lifted from the oil reservoir P moves above the gear portion accommodating space 502 and flows into the oil reservoir 528.

An axial end of the reservoir plate 528 is connected to an oil supply passage not shown. The oil CL accumulated in the oil reservoir 528 flows into the hollow portion 220 of the motor shaft 22 from the end portion on one axial side (+ Y direction side) of the motor shaft 22 through an oil supply passage not shown.

The oil CL flows into the hollow portion 220 of the motor shaft 22. The oil CL in the hollow portion 220 of the motor shaft 22 flows in from the end portion on one axial side (+ Y direction side) of the motor shaft 22 and flows toward the motor 2. For example, the hollow portion 220 of the motor shaft 22 may have a spiral groove therein to supply the oil CL to the motor 2 when the motor shaft 22 rotates. The oil CL flowing through the hollow portion 220 is distributed toward the stator 24 from an oil distribution hole 221 (see fig. 2) provided in the motor shaft 22. The stator 24 is cooled by the oil CL. That is, in the motor unit 1, the oil CL in the oil reservoir P in the gear portion housing space 502 is raised by the gear portion 3, and thereby the oil CL circulates inside the motor unit 1.

In addition, in the motor unit 1, circulation of the oil CL by the pump 4 is performed in addition to the lift by the rotation of the gear portion 3. The oil CL stored in the oil reservoir 54 is sucked by the pump 4 by driving the pump 4. The pump 4 causes the oil CL sucked from the suction port to flow from the discharge port into the oil cooler 8 via the oil pipe portion 56. The oil CL is cooled by heat exchange with the refrigerant in the oil cooler 8, and flows into the oil distribution portion 57 through the oil pipe portion 56. The oil CL flows through the flow path 571 of the oil scattering portion 57 and is scattered from the scattering holes 572 to the motor housing space 501. The oil CL scattered from the scattering holes 572 is blown to the motor 2.

The oil CL blown to the motor 2 flows inside the motor 2. Thereby, the oil CL cools the motor 2. The oil CL that has cooled the motor 2 flows downward by gravity and flows into the oil reservoir 54 connected to the lower side of the motor storage portion 51. In this way, the pump 4 can circulate the oil CL inside the motor housing space 501.

A part of the oil CL kicked up by the gear portion 3 passes through the hollow portion 220 of the motor shaft 22 and flows into the motor housing space 501. The pump 4 circulates the oil CL in the motor housing space 501 and the space inside the oil reservoir 54. Therefore, the oil CL circulated flows into the oil reservoir 54. The internal space of the oil reservoir 54 and the gear portion housing space 502 are divided by a partition wall portion 513. An oil flow hole 515 is formed at the partition wall portion 513. Therefore, a part of the oil CL accumulated in the oil reservoir 54 is caused to flow into the gear portion accommodating space 502. Thereby, the amount of the oil CL stored in the oil reservoir 54 and the oil reservoir P is kept constant.

In this way, in the motor unit 1, the oil CL circulates in the motor housing space 501 and the gear portion housing space 502, thereby lubricating and cooling the motor 2 and the gear portion 3.

While the embodiments of the present invention have been described above, the configurations and combinations thereof in the embodiments are examples, and additions, omissions, substitutions, and other modifications of the configurations can be made without departing from the spirit of the present invention. The present invention is not limited to the embodiments.

Industrial applicability of the invention

The motor unit of the invention can be used as at least a part of a power source of a Hybrid Vehicle (HV), a plug-in hybrid vehicle (PHV), and an Electric Vehicle (EV), for example.

(symbol description)

1 Motor Unit

2 Motor

21 rotor

22 motor shaft

220 hollow part

221 oil dispersing hole

23 rotor core

24 stator

25 stator core

26 coil

281 first motor bearing

282 second Motor bearing

3 gear part

31 speed reducing part

311 first gear

312 second gear

313 third gear

314 intermediate shaft

32 differential part

321 toothed ring

33 output shaft

341 first gear bearing

342 second gear bearing

343 third gear bearing

4 pump

5 outer cover

500 suction pipe

501 motor accommodating space

502 gear portion housing space

51 Motor housing part

511 cylinder part

512 bottom

513 partition wall part

514 through hole

515 oil through hole

52 gear portion housing portion

521 gear portion supporting portion

522 gear portion cover part

523 first output shaft through hole

524 cover barrel part

525 cover bottom

526 cover flange part

527 second output shaft through hole

528 oil storage plate

53 inverter housing part

531 accommodating cover

532 wiring hole

54 oil storage part

541 cooling pipe part

542 cooling pipe portion

55 output shaft support part

551 output bearing

56 oil piping part

561 flow piping part

562 supply pipe section

57 oil spreading part

571 flow path

572 Scattering Aperture

58 Ribs

6 inverter unit

71 inverter cooling passage

72 refrigerant piping

73 connecting piping

74 return pipe

8 oil cooler

Cb vehicle

Cp linker

Dd direction of travel

Sd driving shaft

Tf front wheel

Tr rear wheel

P oil reservoir

CL oil.

Claims

1. A motor unit has:

a motor having a motor shaft that rotates centering on a motor axis extending in a horizontal direction;

a gear portion connected to the motor shaft on one side in a motor axis direction along the motor axis;

a housing that houses the motor and the gear portion; and

a pump that circulates oil contained in the casing,

the housing has:

a motor housing portion that houses the motor; and

a gear portion housing portion that is disposed on one side of the motor housing portion in the motor axis direction and houses the gear portion,

the pump is attached to an outer surface of the gear portion housing portion on one side in the motor axial direction, and at least a portion of the pump overlaps the housing in the motor axial direction.

2. The motor unit according to claim 1,

the housing has an oil piping portion that connects a discharge port of the pump that discharges oil to an oil spreading portion provided in an internal space of the motor housing portion.

3. The motor unit according to claim 2,

the housing further includes an oil reservoir portion that is raised from a lower portion of the motor housing portion in a vertical direction toward a radial outer side of the motor housing portion and that stores the oil,

the pump sucks in the oil stored in the internal space of the oil storage unit.

4. The motor unit according to claim 3,

the casing further has a cooling pipe portion through which a refrigerant that cools the oil stored in the oil storage portion flows.

5. The motor unit according to any one of claims 1 to 4,

an oil cooler that cools oil passing through the oil pipe portion is disposed in a path of the oil pipe portion,

the oil cooler is attached to an outer surface of the gear portion housing portion on one side in the motor axial direction, and at least a portion of the oil cooler overlaps the housing in the motor axial direction.

6. The motor unit according to any one of claims 1 to 5,

the gear portion housing portion has a gear portion supporting portion which extends radially outward from a radially outer surface of one end portion of the motor housing portion in the motor axial direction and is formed of the same member as the motor housing portion,

the oil pipe portion has a tubular shape formed inside the gear portion support portion.

7. The motor unit according to any one of claims 1 to 6,

the housing further has:

a tubular oil distribution portion disposed in the motor housing portion above the motor in the vertical direction and connected to the oil pipe portion,

the oil spreading portion has: a flow passage extending in the motor axial direction and through which the oil flows; and

and a distribution hole connecting the flow path and the motor housing portion.