JP7625786B2 - Drive unit - Google Patents

Description

The present invention relates to a drive device.

Rotating electric machines equipped with a refrigerant injection unit that injects refrigerant into a stator core are known. For example, Patent Document 1 describes a rotating electric machine equipped with a pipe as a refrigerant injection unit.

JP 2019-9967 A

In rotating electric machines such as those described above, there was a need to more efficiently cool the stator core using the refrigerant sprayed from the refrigerant spray section.

In view of the above circumstances, one of the objectives of the present invention is to provide a drive unit having a structure that can improve the cooling efficiency of the stator core.

One aspect of the drive device of the present invention includes a motor having a rotor rotatable about a motor shaft extending in a direction intersecting the vertical direction and a stator core located radially outward of the rotor, a housing that accommodates the motor inside, and a first refrigerant injection unit having an injection port for injecting refrigerant into the stator core. The stator core has a cylindrical stator core body whose outer circumferential surface surrounds the rotor, and a fixing part that protrudes radially outward from the stator core body and is fixed to the housing. The fixing part includes an upper fixing part that protrudes vertically upward from the stator core body. The injection port includes a first injection port located vertically below the vertically upper end of the upper fixing part. The upper fixing part is located on one circumferential side of the first injection port. The opening direction of the first injection port is a direction facing directly downward in the vertical direction, or a direction tilted toward one side in the circumferential direction from a direction facing directly downward in the vertical direction, and is a direction facing a portion of the outer circumferential surface of the stator core body that is located on the other side in the circumferential direction than the boundary with the end of the upper fixed part on the other side in the circumferential direction.

One aspect of the drive device of the present invention includes a motor having a rotor rotatable about a motor shaft extending in a direction intersecting the vertical direction and a stator core located radially outward of the rotor, a housing that accommodates the motor inside, and a first refrigerant injection unit having an injection port for injecting refrigerant into the stator core. The stator core has a cylindrical stator core body whose outer circumferential surface surrounds the rotor, and a fixing part that protrudes radially outward from the stator core body and is fixed to the housing. The fixing part includes an upper fixing part that protrudes vertically upward from the stator core body. The injection port includes a first injection port located vertically below the vertically upper end of the upper fixing part. The upper fixing part is located on one circumferential side of the first injection port. The opening direction of the first injection port is inclined toward one side in the circumferential direction with respect to the direction facing the motor shaft, and faces a portion of the outer circumferential surface of the stator core body that is located on the other side in the circumferential direction than the boundary with the end of the upper fixed part on the other side in the circumferential direction.

According to one aspect of the present invention, the cooling efficiency of the stator core can be improved.

FIG. 1 is a schematic diagram showing a drive device according to a first embodiment. FIG. 2 is a cross-sectional view showing a part of the drive device of the first embodiment, taken along line II-II in FIG. FIG. 3 is a partial cross-sectional perspective view showing a part of the housing of the first embodiment. FIG. 4 is a perspective view showing the stator, the first refrigerant injection portion, and the second refrigerant injection portion of the first embodiment. FIG. 5 is a cross-sectional view showing a part of the stator core and a first refrigerant injection portion of the first embodiment, and is a partially enlarged view of FIG. FIG. 6 is a cross-sectional view showing a part of the drive device of the first embodiment, taken along line VI-VI in FIG. FIG. 7 is a perspective view showing the first refrigerant injection portion of the first embodiment. FIG. 8 is a cross-sectional view showing a part of the stator core and a first refrigerant injection portion of the first embodiment, and is a diagram showing an example of a flow of oil injected from the first injection port. FIG. 9 is a diagram showing a part of the stator core and the first refrigerant injection portion of the first embodiment as viewed from above, illustrating an example of a flow of oil injected from the first injection port. FIG. 10 is a cross-sectional view showing a part of a stator core and a first refrigerant injection portion according to the second embodiment. FIG. 11 is a cross-sectional view showing a part of a stator core, a first refrigerant injection portion, and a third refrigerant injection portion according to the third embodiment.

In the following description, the vertical direction is defined based on the positional relationship when the drive device of each embodiment is mounted on a vehicle positioned on a horizontal road surface. In other words, the relative positional relationship with respect to the vertical direction described in each of the following embodiments only needs to be satisfied when the drive device is mounted on a vehicle positioned on a horizontal road surface.

In the drawings, the XYZ coordinate system is appropriately shown as a three-dimensional orthogonal coordinate system. In the XYZ coordinate system, the Z axis direction is the vertical direction. The +Z side is the upper side in the vertical direction, and the -Z side is the lower side in the vertical direction. In the following description, the upper side in the vertical direction is simply called the "upper side", and the lower side in the vertical direction is simply called the "lower side". The X axis direction is a direction perpendicular to the Z axis direction and is the front-rear direction of the vehicle on which the drive unit is mounted. In each of the following embodiments, the +X side is the front side of the vehicle, and the -X side is the rear side of the vehicle. The Y axis direction is a direction perpendicular to both the X axis direction and the Z axis direction, and is the left-right direction of the vehicle, i.e., the vehicle width direction. In each of the following embodiments, the +Y side is the left side of the vehicle, and the -Y side is the right side of the vehicle. The front-rear direction and the left-right direction are horizontal directions perpendicular to the vertical direction.

Note that the positional relationship in the front-rear direction is not limited to the positional relationship in each of the following embodiments, and the +X side may be the rear side of the vehicle and the -X side may be the front side of the vehicle. In this case, the +Y side is the right side of the vehicle and the -Y side is the left side of the vehicle.

The motor shaft J1, which is shown in each figure as appropriate, extends in a direction intersecting the vertical direction. More specifically, the motor shaft J1 extends in the Y-axis direction perpendicular to the vertical direction, i.e., in the left-right direction of the vehicle. In the following description, unless otherwise specified, the direction parallel to the motor shaft J1 is simply referred to as the "axial direction", the radial direction centered on the motor shaft J1 is simply referred to as the "radial direction", and the circumferential direction centered on the motor shaft J1, i.e., around the axis of the motor shaft J1, is simply referred to as the "circumferential direction". In addition, the side of the circumferential direction that proceeds counterclockwise as viewed from the left side (+Y side) of the vehicle is referred to as the "one circumferential side", and the side of the circumferential direction that proceeds clockwise as viewed from the left side of the vehicle is referred to as the "other circumferential side". The one circumferential side is the side on which the arrow θ, which is shown in each figure as appropriate, proceeds, and the other circumferential side is the opposite side to the side on which the arrow θ proceeds. In this specification, the "parallel direction" also includes a substantially parallel direction, and the "orthogonal direction" also includes a substantially orthogonal direction.

First Embodiment
A drive device 1 according to the present embodiment shown in Fig. 1 is mounted on a vehicle powered by a motor, such as a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHV), or an electric vehicle (EV), and is used as the power source thereof. As shown in Fig. 1, the drive device 1 includes a motor 2, a transmission device 3 including a reduction gear 4 and a differential gear 5, a housing 6, an oil pump 96, a cooler 97, and a refrigerant injection unit 10. Note that in this embodiment, the drive device 1 does not include an inverter unit. In other words, the drive device 1 is structured separately from the inverter unit.

The housing 6 accommodates the motor 2 and the transmission device 3 therein. The housing 6 has a motor accommodating section 61, a gear accommodating section 62, and a partition wall 61c. The motor accommodating section 61 accommodates the rotor 20 and the stator 30 described later. The motor accommodating section 61 surrounds the stator core 32 described later from the radial outside. The gear accommodating section 62 accommodates the transmission device 3 therein. The gear accommodating section 62 is located on the left side of the motor accommodating section 61. The bottom 61a of the motor accommodating section 61 is located above the bottom 62a of the gear accommodating section 62. The partition wall 61c axially divides the interior of the motor accommodating section 61 from the interior of the gear accommodating section 62. The partition wall 61c is provided with a partition wall opening 68. The partition wall opening 68 connects the interior of the motor accommodating section 61 to the interior of the gear accommodating section 62. The partition 61c is located on the left side of the stator 30.

The housing 6 contains oil O as a refrigerant inside. In this embodiment, the oil O is contained inside the motor housing portion 61 and inside the gear housing portion 62. An oil reservoir P in which the oil O accumulates is provided in the lower region inside the gear housing portion 62. The oil O in the oil reservoir P is sent to the inside of the motor housing portion 61 by an oil passage 90 described below. The oil O sent to the inside of the motor housing portion 61 accumulates in the lower region inside the motor housing portion 61. At least a portion of the oil O that has accumulated inside the motor housing portion 61 moves to the gear housing portion 62 through the partition opening 68 and returns to the oil reservoir P.

In this specification, "oil is stored inside a certain part" means that oil is located inside a certain part at least part of the time while the motor is running, and oil does not have to be located inside a certain part when the motor is stopped. For example, in this embodiment, oil O is stored inside the motor housing part 61 means that oil O is located inside the motor housing part 61 at least part of the time while the motor 2 is running, and when the motor 2 is stopped, all of the oil O inside the motor housing part 61 may have moved to the gear housing part 62 through the partition opening 68. Note that a portion of the oil O sent to the inside of the motor housing part 61 by the oil passage 90 described later may remain inside the motor housing part 61 when the motor 2 is stopped.

The oil O circulates in the oil passage 90, which will be described later. The oil O is used to lubricate the reduction gear 4 and the differential gear 5. The oil O is also used to cool the motor 2. As the oil O, it is preferable to use an oil equivalent to the lubricating oil for automatic transmissions (ATF: Automatic Transmission Fluid), which has a relatively low viscosity, in order to function as a lubricating oil and a cooling oil.

2 and 3, the housing 6 has a support portion 65 that protrudes radially inward from the inner peripheral surface of the motor accommodating portion 61. The support portion 65 contacts the outer peripheral surface of the stator core body 32a described later. The support portion 65 includes a first support portion 63 and a second support portion 64. In this embodiment, a plurality of first support portions 63 and a plurality of second support portions 64 are provided. For example, two of each of the first support portions 63 and the second support portions 64 are provided. The two first support portions 63 are arranged at intervals in the circumferential direction. The two second support portions 64 are arranged at intervals in the circumferential direction. In this embodiment, the first support portion 63 is located above the motor shaft J1 and rearward of the motor shaft J1. In this embodiment, the second support portion 64 is located above the motor shaft J1 and forward of the motor shaft J1.

As shown in FIG. 3, the first support portion 63 and the second support portion 64 extend in the axial direction. The radial inner surface of the first support portion 63 and the radial inner surface of the second support portion 64 are curved surfaces. As shown in FIG. 2, the radial inner surface of the first support portion 63 and the radial inner surface of the second support portion 64 are arc-shaped about the motor shaft J1 when viewed in the axial direction. The radial inner surface of the first support portion 63 and the radial inner surface of the second support portion 64 contact the outer peripheral surface of the stator core body 32a described later.

As shown in FIG. 3, the first support portion 63 has a first through groove 63a that penetrates the first support portion 63 in the circumferential direction. The first through groove 63a is recessed radially outward. For example, a plurality of first through grooves 63a are provided for each first support portion 63 at intervals in the axial direction. For example, two first through grooves 63a are provided for each first support portion 63. The axial positions of the two first through grooves 63a provided in one first support portion 63 are the same as the axial positions of the two first through grooves 63a provided in the other first support portion 63, for example.

The second support portion 64 has a second through groove 64a that penetrates the second support portion 64 in the circumferential direction. The second through groove 64a is recessed radially outward. For example, a plurality of second through grooves 64a are provided for each second support portion 64 with an axial gap therebetween. For example, two second through grooves 64a are provided for each second support portion 64. The axial positions of the two second through grooves 64a provided in one second support portion 64 are the same as the axial positions of the two second through grooves 64a provided in the other second support portion 64, for example.

The axial position of one of the first through grooves 63a in each first support portion 63 and the axial position of one of the second through grooves 64a in each second support portion 64 are, for example, the same as each other. The axial position of the other of the first through grooves 63a in each first support portion 63 and the axial position of the other of the second through grooves 64a in each second support portion 64 are, for example, the same as each other.

In this specification, "certain parameters are the same" includes cases where certain parameters are strictly the same as each other, as well as cases where certain parameters are approximately the same as each other. "certain parameters are approximately the same as each other" includes, for example, certain parameters slightly differing from each other within the tolerance range.

As shown in FIG. 2, the housing 6 has a protrusion 66 provided on the inner circumferential surface of the motor accommodating portion 61. The protrusion 66 protrudes radially inward from the inner circumferential surface of the motor accommodating portion 61. The protrusion 66 protrudes toward the stator core 32 described below. The protrusion 66 is located circumferentially between the upper fixing portion 32f described below and the first refrigerant injection portion 11. More specifically, the radially inner end of the protrusion 66 is located circumferentially between the upper end of the upper fixing portion 32f and the upper end of the first refrigerant injection portion 11.

In this embodiment, the motor 2 is an inner rotor type motor. The motor 2 includes a rotor 20, a stator 30, and bearings 26 and 27. The rotor 20 can rotate around a motor axis J1 that extends in the horizontal direction. The rotor 20 includes a shaft 21 and a rotor body 24. Although not shown, the rotor body 24 includes a rotor core and a rotor magnet fixed to the rotor core. The torque of the rotor 20 is transmitted to the transmission device 3.

The shaft 21 extends in the axial direction around the motor shaft J1. The shaft 21 rotates around the motor shaft J1. The shaft 21 is a hollow shaft with a hollow section 22 inside. The shaft 21 is provided with a communication hole 23. The communication hole 23 extends in the radial direction and connects the hollow section 22 to the outside of the shaft 21.

The shaft 21 extends across the motor housing 61 and the gear housing 62 of the housing 6. The left end of the shaft 21 protrudes into the gear housing 62. A first gear 41 (described later) of the transmission device 3 is fixed to the left end of the shaft 21. The shaft 21 is rotatably supported by bearings 26 and 27.

The stator 30 faces the rotor 20 in the radial direction with a gap therebetween. More specifically, the stator 30 is located radially outside the rotor 20. The stator 30 has a stator core 32 and a coil assembly 33. That is, the motor 2 has the stator core 32 and the coil assembly 33. The stator core 32 is located radially outside the rotor 20. The stator core 32 surrounds the rotor 20. The stator core 32 is fixed to the inner circumferential surface of the motor housing portion 61.

2 and 4, the stator core 32 has a stator core body 32a and a fixing portion 32b. The outer peripheral surface of the stator core body 32a is cylindrical and surrounds the rotor 20. The outer peripheral surface of the stator core body 32a is cylindrical, for example, centered on the motor shaft J1. As shown in FIG. 2, the stator core body 32a has a cylindrical core back 32d extending in the axial direction and a plurality of teeth 32e extending radially inward from the core back 32d. The outer peripheral surface of the core back 32d is the outer peripheral surface of the stator core body 32a. The multiple teeth 32e are arranged at equal intervals around the circumference.

The fixing portion 32b protrudes radially outward from the outer peripheral surface of the stator core body 32a. The fixing portion 32b is the portion that is fixed to the housing 6. As shown in FIG. 4, the fixing portion 32b extends in the axial direction. For example, the fixing portion 32b extends from the left end (+Y side) of the stator core body 32a to the right end (-Y side) of the stator core body 32a. A plurality of the fixing portions 32b are provided at intervals along the circumferential direction. As shown in FIG. 2, for example, four fixing portions 32b are provided.

The fixing portion 32b includes an upper fixing portion 32f, a lower fixing portion 32g, a front fixing portion 32h, and a rear fixing portion 32i. The upper fixing portion 32f protrudes upward from the stator core body 32a. The lower fixing portion 32g protrudes downward from the stator core body 32a. The front fixing portion 32h protrudes forward from the stator core body 32a. The rear fixing portion 32i protrudes rearward from the stator core body 32a. The upper fixing portion 32f, the lower fixing portion 32g, the front fixing portion 32h, and the rear fixing portion 32i are arranged, for example, at equal intervals around one circumference in the circumferential direction.

In this specification, "a certain object protrudes from another object to a certain side" means that the certain object protrudes in a direction toward a certain side as it moves away from the other object. For example, "the fixed portion 32b protrudes upward from the stator core body 32a" means that the fixed portion 32b protrudes in a direction toward the upper side as it moves away from the stator core body 32a radially outward. In other words, "the fixed portion 32b protrudes upward from the stator core body 32a" includes, for example, the fixed portion 32b protruding directly upward from the stator core body 32a in the vertical direction and the fixed portion 32b protruding from the stator core body 32a in a direction inclined within a range of less than 90° from the vertical direction directly upward.

In the case where the fixed portion 32b protrudes radially outward from a cylindrical surface centered on the motor axis J1 as in this embodiment, if the fixed portion 32b protrudes in a direction that positions upward as it moves away from the stator core body 32a in the radial direction, the radial outer end of the fixed portion 32b is positioned above the motor axis J1. In other words, in this embodiment, "the fixed portion 32b protrudes upward from the stator core body 32a" also includes the radial outer end of the fixed portion 32b being positioned above the motor axis J1.

The upper fixing portion 32f protrudes, for example, diagonally forward and upward. The radial outer end of the upper fixing portion 32f is located above the motor shaft J1. The upper fixing portion 32f is disposed away from the inner peripheral surface of the motor housing portion 61. As shown in FIG. 5, the circumferential dimension of the upper fixing portion 32f decreases toward the radially outer side. The outer shape of the radial outer end of the upper fixing portion 32f is an arc shape that is convex radially outward when viewed in the axial direction. The radial outer end of the upper fixing portion 32f is located above the upper end of the stator core body 32a.

The surface of the upper fixing portion 32f on the other circumferential side (-θ side) is positioned lower as it approaches the other circumferential side. In this embodiment, the surface of the upper fixing portion 32f on the other circumferential side is curved. The surface of the upper fixing portion 32f on the other circumferential side smoothly connects to the outer peripheral surface of the stator core body 32a at the boundary BP with the end of the upper fixing portion 32f on the other circumferential side (-θ side) of the outer peripheral surface of the stator core body 32a.

The upper end of the upper fixing portion 32f is located on one circumferential side (+θ side) of the upper vertex VP of the stator core body 32a. The vertex VP is the uppermost part of the outer circumferential surface of the stator core body 32a. When viewed in the axial direction, the vertex VP is the part of the outer circumferential surface of the stator core body 32a that intersects with an imaginary line IL1 that passes through the motor shaft J1 and extends vertically.

In this embodiment, the end of the upper fixing portion 32f on one circumferential side (+θ side) is located on one circumferential side of the vertex VP. The end of the upper fixing portion 32f on the other circumferential side (-θ side) is located on the other circumferential side of the vertex VP. That is, in this embodiment, the upper fixing portion 32f is provided at the position of the vertex VP. More specifically, the other circumferential side portion of the upper fixing portion 32f is provided at the position of the vertex VP.

Therefore, the vertex VP cannot be seen from the outside. In this case, as shown in FIG. 5, the vertex VP is located on a virtual curve IL4 that virtually shows the outer peripheral surface of the stator core body 32a at the portion where the upper fixing portion 32f is provided. The virtual curve IL4 is an arc shape centered on the motor shaft J1, and smoothly connects the portions of the outer peripheral surface of the stator core body 32a that are located on both sides of the upper fixing portion 32f in the circumferential direction. In this way, when the upper vertex of the stator core body 32a cannot be seen due to the fixing portion 32b, etc., the uppermost portion on a virtual extension line assumed from the visible portion of the outer peripheral surface of the stator core body 32a is regarded as the upper vertex of the stator core body 32a.

In this embodiment, the boundary BP between the outer peripheral surface of the stator core body 32a and the end of the upper fixing portion 32f on the other circumferential side (-θ side) is located on the other circumferential side of the apex VP. The radial distance L2 between the upper fixing portion 32f and the inner peripheral surface of the motor accommodating portion 61 is, at least in part, smaller than the radial distance L1 between the boundary BP and the inner peripheral surface of the motor accommodating portion 61. In this embodiment, the distance L2 is smaller than the distance L1 in every part of the upper fixing portion 32f. In this embodiment, the distance L1 is the radial distance between the boundary BP and the radially inner surface of the protrusion 66.

As shown in FIG. 2, the lower fixing portion 32g, for example, protrudes diagonally downward and downward. The front fixing portion 32h, for example, protrudes diagonally downward and forward. The rear fixing portion 32i, for example, protrudes diagonally upward and backward. In this embodiment, the lower fixing portion 32g, the front fixing portion 32h, and the rear fixing portion 32i are positioned away from the inner peripheral surface of the motor housing portion 61. The shapes of the lower fixing portion 32g, the front fixing portion 32h, and the rear fixing portion 32i are, for example, similar to the shape of the upper fixing portion 32f.

The fixing portion 32b has a through hole 32c that passes through the fixing portion 32b in the axial direction. A bolt 34 extending in the axial direction is passed through the through hole 32c. The bolt 34 is passed through the through hole 32c from the right side (-Y side) and screwed into the female screw hole 35 shown in FIG. 6. The female screw hole 35 is provided in the partition wall 61c. The fixing portion 32b is fixed to the partition wall 61c by screwing the bolt 34 into the female screw hole 35. In this way, the stator 30 is fixed to the housing 6 by the bolt 34.

As shown in FIG. 1, the coil assembly 33 has multiple coils 31 attached to the stator core 32 in the circumferential direction. The multiple coils 31 are attached to each tooth 32e of the stator core 32 via insulators (not shown). The multiple coils 31 are arranged in the circumferential direction. More specifically, the multiple coils 31 are arranged at equal intervals around the circumference. Although not shown, the coil assembly 33 may have a bundling member or the like that bundles the coils 31 together, or may have jumper wires that connect the coils 31 together.

The coil assembly 33 has coil ends 33a and 33b that protrude in the axial direction from the stator core 32. The coil end 33a is a portion that protrudes to the right from the stator core 32. The coil end 33b is a portion that protrudes to the left from the stator core 32. The coil end 33a includes a portion of each coil 31 included in the coil assembly 33 that protrudes to the right of the stator core 32. The coil end 33b includes a portion of each coil 31 included in the coil assembly 33 that protrudes to the left of the stator core 32. As shown in FIG. 4, in this embodiment, the coil ends 33a and 33b are annular with the motor shaft J1 as the center. Although not shown, the coil ends 33a and 33b may include a bundling member that bundles the coils 31 together, or may include a crossover wire that connects the coils 31 together.

As shown in FIG. 1, the bearings 26 and 27 rotatably support the rotor 20. The bearings 26 and 27 are, for example, ball bearings. The bearing 26 rotatably supports a portion of the rotor 20 located to the right of the stator core 32. In this embodiment, the bearing 26 supports a portion of the shaft 21 located to the right of the portion to which the rotor body 24 is fixed. The bearing 26 is held by a wall portion 61b of the motor housing portion 61 that covers the right side of the rotor 20 and the stator 30.

The bearing 27 rotatably supports a portion of the rotor 20 located to the left of the stator core 32. In this embodiment, the bearing 27 supports a portion of the shaft 21 located to the left of the portion to which the rotor body 24 is fixed. The bearing 27 is held by the partition wall 61c.

The transmission device 3 is accommodated in the gear accommodating portion 62 of the housing 6. The transmission device 3 is connected to the motor 2. More specifically, the transmission device 3 is connected to the left end of the shaft 21. The transmission device 3 has a reduction gear 4 and a differential gear 5. The torque output from the motor 2 is transmitted to the differential gear 5 via the reduction gear 4.

The reduction gear 4 is connected to the motor 2. The reduction gear 4 reduces the rotational speed of the motor 2 and increases the torque output from the motor 2 according to the reduction ratio. The reduction gear 4 transmits the torque output from the motor 2 to the differential gear 5. The reduction gear 4 has a first gear 41, a second gear 42, a third gear 43, and an intermediate shaft 45.

The first gear 41 is fixed to the outer peripheral surface at the left end of the shaft 21. The first gear 41 rotates together with the shaft 21 around the motor axis J1. The intermediate shaft 45 extends along an intermediate axis J2 parallel to the motor shaft J1. The intermediate shaft 45 rotates around the intermediate axis J2. The second gear 42 and the third gear 43 are fixed to the outer peripheral surface of the intermediate shaft 45. The second gear 42 and the third gear 43 are connected via the intermediate shaft 45. The second gear 42 and the third gear 43 rotate around the intermediate axis J2. The second gear 42 meshes with the first gear 41. The third gear 43 meshes with a ring gear 51 of the differential device 5, which will be described later.

The torque output from the motor 2 is transmitted to the ring gear 51 of the differential device 5 via the shaft 21, the first gear 41, the second gear 42, the intermediate shaft 45, and the third gear 43 in this order. The gear ratio of each gear and the number of gears can be changed according to the required reduction ratio. In this embodiment, the reduction device 4 is a parallel shaft gear type reducer in which the axes of the gears are arranged in parallel.

The differential device 5 is connected to the motor 2 via the reduction gear 4. The differential device 5 is a device for transmitting the torque output from the motor 2 to the wheels of the vehicle. When the vehicle turns, the differential device 5 transmits the same torque to the axles 55 of the left and right wheels while absorbing the speed difference between the left and right wheels. In this manner, in this embodiment, the transmission device 3 transmits the torque of the motor 2 to the axles 55 of the vehicle via the reduction gear 4 and the differential device 5. The differential device 5 has a ring gear 51, 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). The ring gear 51 rotates around a differential shaft J3 that is parallel to the motor shaft J1. The torque output from the motor 2 is transmitted to the ring gear 51 via the reduction gear 4.

The motor 2 is provided with an oil passage 90 through which the oil O circulates inside the housing 6. The oil passage 90 is a path for the oil O that supplies the oil O from the oil reservoir P to the motor 2 and guides it back to the oil reservoir P. The oil passage 90 is provided across the interior of the motor housing portion 61 and the interior of the gear housing portion 62.

In this specification, "oil passage" means the path of oil. Therefore, "oil passage" is a concept that includes not only a "flow path" that creates a steady flow of oil in one direction, but also a path that temporarily retains oil and a path through which oil drips. A path that temporarily retains oil includes, for example, a reservoir that stores oil.

The oil passage 90 has a first oil passage 91 and a second oil passage 92. The first oil passage 91 and the second oil passage 92 each circulate the oil O inside the housing 6. The first oil passage 91 has a scooping passage 91a, a shaft supply passage 91b, an inner shaft passage 91c, and an inner rotor passage 91d. In addition, a first reservoir 93 is provided in the first oil passage 91. The first reservoir 93 is provided in the gear housing portion 62.

The scooping path 91a is a path that scoops up oil O from the oil pool P by the rotation of the ring gear 51 of the differential device 5, and receives the oil O in the first reservoir 93. The first reservoir 93 opens on the upper side. The first reservoir 93 receives the oil O scooped up by the ring gear 51. In addition, when the liquid level S of the oil pool P is high, such as immediately after the motor 2 is driven, the first reservoir 93 also receives the oil O scooped up by the second gear 42 and the third gear 43 in addition to the ring gear 51.

The shaft supply path 91b guides oil O from the first reservoir 93 to the hollow portion 22 of the shaft 21. The shaft internal path 91c is a path through which the oil O passes inside the hollow portion 22 of the shaft 21. The rotor internal path 91d is a path through which the oil O passes from the communication hole 23 of the shaft 21 through the inside of the rotor body 24 and splashes onto the stator 30.

In the shaft passage 91c, centrifugal force is applied to the oil O inside the rotor 20 as the rotor 20 rotates. As a result, the oil O is continuously scattered radially outward from the rotor 20. As the oil O is scattered, the passage inside the rotor 20 becomes negative pressure, and the oil O that has accumulated in the first reservoir 93 is sucked into the rotor 20, filling the passage inside the rotor 20 with oil O.

Oil O that reaches the stator 30 removes heat from the stator 30. After cooling the stator 30, the oil O drips downward and accumulates in the lower area of the motor housing 61. The oil O that accumulates in the lower area of the motor housing 61 moves to the gear housing 62 through the partition opening 68 provided in the partition 61c. In this way, the first oil passage 91 supplies oil O to the rotor 20 and the stator 30.

In the second oil passage 92, oil O is drawn up from an oil reservoir P and supplied to the stator 30. The second oil passage 92 is provided with an oil pump 96, a cooler 97, and a refrigerant injection unit 10. The second oil passage 92 has a first flow path 92a, a second flow path 92b, a third flow path 92c, and a fourth flow path 94.

The first flow path 92a, the second flow path 92b, and the third flow path 92c are provided in the wall of the housing 6. The first flow path 92a connects the oil reservoir P and the oil pump 96. The second flow path 92b connects the oil pump 96 and the cooler 97. The third flow path 92c connects the cooler 97 and the fourth flow path 94. The third flow path 92c is provided, for example, in the front (+X side) wall of the motor housing section 61.

The fourth flow passage 94 is provided in the partition wall 61c. The fourth flow passage 94 connects the first refrigerant injection section 11 and the second refrigerant injection section 12 of the refrigerant injection section 10, which will be described later. As shown in FIG. 6, the fourth flow passage 94 has an inlet section 94a, a first branch section 94c, and a second branch section 94f. The inlet section 94a is a portion of the fourth flow passage 94 into which oil O flows from the third flow passage 92c. The inlet section 94a extends rearward (-X side) from the third flow passage 92c. The inlet section 94a is located on the front side (+X side) of the shaft 21, and extends linearly in the front-rear direction of the radial direction. The inner diameter of the inlet section 94a is larger at the front end. In this embodiment, the front end of the inlet section 94a is the radially outer end of the inlet section 94a.

The front (+X) end of the inlet portion 94a is located radially outward from the fixed portion 32b. The rear (-X) end of the inlet portion 94a is located radially inward from the fixed portion 32b. That is, in this embodiment, the inlet portion 94a extends in the front-rear direction from radially outward from the fixed portion 32b to radially inward from the fixed portion 32b. The inlet portion 94a is located above the front fixed portion 32h.

The rear end (-X side) of the inlet portion 94a is a connection portion 94b where the first branch portion 94c and the second branch portion 94f are connected. The inner diameter of the inlet portion 94a is larger at the connection portion 94b. The connection portion 94b is located radially inward from the fixing portion 32b.

The inlet portion 94a, excluding the connection portion 94b, is made, for example, by drilling holes from the front side (+X side) of the housing 6. The front end of the inlet portion 94a is blocked by tightening a bolt 95a. The connection portion 94b of the inlet portion 94a is made, for example, by drilling holes from the left side (+Y side) of the partition wall 61c. Although not shown in the figure, the left end of the connection portion 94b is blocked by tightening a bolt.

The first branch portion 94c is a portion that branches off from the inlet portion 94a and extends to the first refrigerant injection portion 11, which will be described later. The first branch portion 94c extends diagonally upward and rearward from the rear (-X side) end of the inlet portion 94a, i.e., the connection portion 94b. The first branch portion 94c passes through a portion of the partition wall 61c that is located below the upper fixing portion 32f and above the shaft 21, and extends to the upper end of the partition wall 61c. The radial position of the upper end of the first branch portion 94c is approximately the same as the radial position of the fixing portion 32b. The upper end of the first branch portion 94c is located rearward of the upper fixing portion 32f.

The first branch portion 94c has an extension portion 94d that extends in a straight line from the connection portion 94b diagonally upward toward the rear, and a connection portion 94e that connects to the upper end of the extension portion 94d. The connection portion 94e is the upper end of the first branch portion 94c, and is the portion to which the first refrigerant injection portion 11 described below is connected. The inner diameter of the connection portion 94e is larger than the inner diameter of the extension portion 94d. The connection portion 94e is made, for example, by drilling a hole from the upper side of the housing 6. The upper end of the connection portion 94e is closed by tightening a bolt 95b. The extension portion 94d is made, for example, by drilling a hole from the upper side of the housing 6 diagonally downward toward the front through the inside of the connection portion 94e.

The second branch portion 94f is a portion that branches off from the inlet portion 94a and extends to the second refrigerant injection portion 12 described later. In this embodiment, the second branch portion 94f extends obliquely upward from the connection portion 94b to the front side. The second branch portion 94f extends linearly, inclined to the right side (-Y side) in the front-rear direction. The radial position of the front end (+X side) of the second branch portion 94f is approximately the same as the radial position of the fixing portion 32b. The front end (+X side) of the second branch portion 94f is located above the front fixing portion 32h. The front end of the second branch portion 94f and the front fixing portion 32h are located at approximately the same position in the front-rear direction. The second branch portion 94f is made, for example, by drilling a hole from the left side (+Y side) of the partition wall 61c through the inside of the connection portion 94b.

In the fourth flow passage 94, the rear portion of the inlet 94a, the portion of the extension 94d excluding the upper end, and the rear portion of the second branch 94f are provided in a portion of the partition 61c that is located radially inward from the fixed portion 32b. That is, in this embodiment, the fourth flow passage 94 has a portion that passes radially inward from the fixed portion 32b.

As shown in FIG. 1, the refrigerant injection unit 10 extends in the axial direction. The left end of the refrigerant injection unit 10 is fixed to the partition wall 61c. As shown in FIG. 4, the refrigerant injection unit 10 includes a first refrigerant injection unit 11 and a second refrigerant injection unit 12. That is, the drive device 1 includes the first refrigerant injection unit 11 and the second refrigerant injection unit 12.

In this embodiment, the first refrigerant injection unit 11 and the second refrigerant injection unit 12 are pipes extending in the axial direction of the motor shaft J1. More specifically, the first refrigerant injection unit 11 and the second refrigerant injection unit 12 are cylindrical and extend linearly in the axial direction. The first refrigerant injection unit 11 and the second refrigerant injection unit 12 are parallel to each other. As shown in FIG. 2, the first refrigerant injection unit 11 and the second refrigerant injection unit 12 are accommodated inside the housing 6. The first refrigerant injection unit 11 and the second refrigerant injection unit 12 are located radially outside the stator 30. The first refrigerant injection unit 11 and the second refrigerant injection unit 12 are arranged with a circumferential gap between them. The radial position of the first refrigerant injection unit 11 and the radial position of the second refrigerant injection unit 12 are, for example, the same as each other.

In this specification, "the first refrigerant injection part and the second refrigerant injection part extend linearly in the axial direction of the motor shaft" includes not only the case where the first refrigerant injection part and the second refrigerant injection part extend linearly in the axial direction strictly, but also the case where the first refrigerant injection part and the second refrigerant injection part extend linearly in the axial direction approximately. That is, in this embodiment, "the first refrigerant injection part 11 and the second refrigerant injection part 12 extend linearly in the axial direction" may mean, for example, that the first refrigerant injection part 11 and the second refrigerant injection part 12 extend slightly tilted relative to the axial direction. In this case, the tilt direction of the first refrigerant injection part 11 relative to the axial direction and the tilt direction of the second refrigerant injection part 12 relative to the axial direction may be the same or different.

In this embodiment, the first refrigerant injection unit 11 is located above the stator 30. Here, in this specification, "a certain object is located on one side of another object in a predetermined direction" includes a state where, when the drive unit is arranged on a horizontal plane and the certain object and the other object are viewed from one side in a predetermined direction, the certain object and the other object overlap with each other and the certain object is located in front of the other object. That is, in this embodiment, when the drive unit 1 is arranged on a horizontal plane and the first refrigerant injection unit 11 and the stator 30 are viewed from above, the first refrigerant injection unit 11 and the stator 30 overlap with each other and the first refrigerant injection unit 11 is located in front of the stator 30. In this specification, "a state where the drive unit is arranged on a horizontal plane" includes a state where a vehicle equipped with the drive unit is arranged on a horizontal road surface.

The first refrigerant injection part 11 is located above the second refrigerant injection part 12. In this embodiment, the radial position of the first refrigerant injection part 11 is the same as the radial position of the fixed part 32b. The first refrigerant injection part 11 is located on the rear side (-X side) of the upper fixed part 32f. The first refrigerant injection part 11 is located on the other circumferential side (-θ side) of the upper fixed part 32f. The radial position of the first refrigerant injection part 11 at the radial outer end is approximately the same as the radial position of the radial outer end of the upper fixed part 32f. The first refrigerant injection part 11 is located circumferentially between the upper fixed part 32f and the first support part 63. In this embodiment, the first support part 63 is located on the other circumferential side of the first refrigerant injection part 11.

As shown in FIG. 7, the first refrigerant injection section 11 has a first pipe body section 11a, a small diameter section 11b provided at the left end (+Y side) of the first pipe body section 11a, and a small diameter section 11c provided at the right end (-Y side) of the first pipe body section 11a.

The small diameter portion 11b is the end portion on the left side (+Y side) of the first refrigerant injection portion 11. The small diameter portion 11c is the end portion on the right side (-Y side) of the first refrigerant injection portion 11. The outer diameter of the small diameter portions 11b and 11c is smaller than the outer diameter of the first pipe main body portion 11a. The first refrigerant injection portion 11 is fixed to the partition wall 61c by inserting the small diameter portion 11b into the partition wall 61c from the right side. The small diameter portion 11b opens to the left side. As shown in FIG. 6, the small diameter portion 11b opens to the connection portion 94e of the first branch portion 94c. This connects the first refrigerant injection portion 11 to the fourth flow path 94.

As shown in FIG. 7, an attachment member 16 is provided on the right-hand end (-Y side) of the first refrigerant injection part 11. The attachment member 16 is a rectangular plate with its plate surface facing the axial direction. The attachment member 16 has a recess 16a recessed to the right from the left-hand (+Y side) surface. The right-hand end of the first refrigerant injection part 11, i.e., the small diameter part 11c, is fitted into and fixed to the recess 16a. The right-hand end of the first refrigerant injection part 11 is blocked by the attachment member 16.

The mounting member 16 has a hole 16b that passes through the mounting member 16 in the axial direction. As shown in FIG. 4, a bolt 18 is passed through the hole 16b from the right side (-Y side). The bolt 18 passes through the hole 16b and is fastened from the right side into the first support portion 63 shown in FIG. 2. The mounting member 16 is fixed to the first support portion 63 by fastening the bolt 18 to the first support portion 63. As a result, the right end of the first refrigerant injection portion 11 is fixed to the motor accommodating portion 61 via the mounting member 16.

As shown in FIG. 7, the first refrigerant injection unit 11 has a supply port 13 and a first injection port 14. The supply port 13 and the first injection port 14 are provided on the outer surface of the first refrigerant injection unit 11. The supply port 13 and the first injection port 14 are, for example, circular. Oil O that flows into the first refrigerant injection unit 11 is discharged from the supply port 13 and the first injection port 14. The supply port 13 and the first injection port 14 are openings that open on the outer peripheral surface of the first refrigerant injection unit 11 among the openings of the hole that penetrates the wall portion of the first refrigerant injection unit 11 from the inner peripheral surface to the outer peripheral surface. Specifically, as shown in FIG. 5, the first injection port 14 is an opening that opens on the outer peripheral surface of the first refrigerant injection unit 11 among the openings of the hole 11d that penetrates the wall portion of the first refrigerant injection unit 11 from the inner peripheral surface to the outer peripheral surface.

As shown in FIG. 7, in this embodiment, the supply ports 13 are provided in multiples at both ends of the first pipe body 11a in the axial direction. For example, four supply ports 13 are provided at both ends of the first pipe body 11a in the axial direction. The four supply ports 13 provided at the right end (-Y side) of the first pipe body 11a are arranged in a zigzag pattern along the circumferential direction. The four supply ports 13 provided at the right end of the first pipe body 11a include one supply port 13 that opens directly below, two supply ports 13 that open diagonally forward below, and one supply port 13 that opens diagonally backward below. The four supply ports 13 provided at the left end (+Y side) of the first pipe body 11a are arranged in the same manner as the four supply ports 13 provided at the right part of the first pipe body 11a, except for their axial positions.

As shown in FIG. 4, of the multiple supply ports 13, the four supply ports 13 on the right side (-Y side) are located above the coil end 33a. Of the multiple supply ports 13, the four supply ports 13 on the left side (+Y side) are located above the coil end 33b. Therefore, oil O discharged from the supply ports 13 is supplied to the coil ends 33a, 33b from above. In this way, the supply ports 13 supply oil O to the coil ends 33a, 33b. Therefore, the coil ends 33a, 33b can be cooled.

In particular, in this embodiment, the first refrigerant injection unit 11 is located above the stator 30, so that the oil O from the supply port 13 can be supplied from above the coil ends 33a, 33b. This allows the oil O from the supply port 13 to flow from the upper side to the lower side of the coil ends 33a, 33b using gravity. This makes it easier to supply the oil O to the entire coil ends 33a, 33b, and easier to cool the entire coil ends 33a, 33b.

In addition, according to this embodiment, the supply ports 13 of the first refrigerant injection unit 11 are arranged in multiples above each coil end 33a, 33b. This allows a large amount of oil O to be supplied from the first refrigerant injection unit 11 to the coil ends 33a, 33b. This allows the coil 31, which is a heat generating body, to be cooled effectively, and the stator 30 to be cooled even more effectively.

In addition, according to this embodiment, the multiple supply ports 13 located above each coil end 33a, 33b are arranged in a zigzag pattern along the circumferential direction. Therefore, the axial positions of the multiple supply ports 13 arranged along the circumferential direction are shifted alternately. This makes it easier to supply oil O to the entire coil ends 33a, 33b than when the axial positions of the multiple supply ports 13 located above each coil end 33a, 33b are the same.

In addition, according to this embodiment, the supply ports 13 located above each coil end 33a, 33b include a supply port 13 facing downward diagonally forward and a supply port 13 facing downward diagonally backward. Therefore, it is easy to supply oil O supplied from the multiple supply ports 13 to both the front and rear portions of the coil ends 33a, 33b, and it is easy to supply oil O to the entire coil ends 33a, 33b. This allows the coil ends 33a, 33b to be cooled more effectively, and the stator 30 to be cooled even more effectively.

The first injection port 14 is an injection port that injects oil O into the stator core 32. That is, the injection port of the first refrigerant injection unit 11 includes the first injection port 14. The first injection port 14 is provided in a portion of the first refrigerant injection unit 11 that overlaps with the stator core 32 when viewed from the radial outside. In this embodiment, two first injection ports 14 are provided in the first pipe main body portion 11a with a gap in the axial direction. The two first injection ports 14 are located axially between a plurality of supply ports 13 provided at one axial end of the first pipe main body portion 11a and a plurality of supply ports 13 provided at the other axial end of the first pipe main body portion 11a.

As shown in FIG. 5, the first jet nozzle 14 is located on the other circumferential side of the upper fixed portion 32f. In other words, the upper fixed portion 32f is located on one circumferential side of the first jet nozzle 14. The first jet nozzle 14 is disposed facing and spaced apart from the rear side of the upper fixed portion 32f. The first jet nozzle 14 is located on the other circumferential side (-θ side) of the vertex VP of the stator core body 32a. The first jet nozzle 14 is located below the upper end of the upper fixed portion 32f.

The direction D1 in which the first injection port 14 opens is tilted toward one circumferential side (+θ side) from the direction facing directly downward in the vertical direction. In this embodiment, among the injection ports that inject oil O into the stator core 32, the injection ports of the first refrigerant injection unit 11 include only the first injection port 14 that opens in a direction tilted toward one circumferential side from the direction facing directly downward in the vertical direction.

The direction D1 in which the first injection port 14 opens is, for example, a direction inclined to one side in the circumferential direction with respect to the direction facing the motor axis J1. The direction facing the motor axis J1 is the radially inward direction. The direction facing the motor axis J1 in the first refrigerant injection part 11 includes, for example, a direction facing radially inward along the imaginary line IL3. The imaginary line IL3 is an imaginary line that extends radially through the motor axis J1 and the center point CP of the first refrigerant injection part 11 when viewed in the axial direction. The center point CP is a point located at the center of the cylindrical first refrigerant injection part 11 when viewed in the axial direction.

The direction D1 in which the first injection port 14 opens is a direction toward a portion of the outer peripheral surface of the stator core body 32a that is located on the other circumferential side of the boundary BP with the end of the upper fixed portion 32f on the other circumferential side (-θ side).

Here, the point where the imaginary line IL2 passing through the first injection port 14 and the motor shaft J1 intersects with the outer peripheral surface of the stator core body 32a in the axial direction is defined as the intersection point IP. The intersection point IP is a portion located radially inside the first injection port 14. The imaginary line IL2 passes through the center of the first injection port 14 and the motor shaft J1 in the axial direction and extends radially. In this embodiment, the direction D1 in which the first injection port 14 opens is a direction facing the region Rg located between the boundary BP and the intersection point IP in the circumferential direction of the outer peripheral surface of the stator core body 32a. The region Rg is a portion of the outer peripheral surface of the stator core body 32a between the boundary BP and the portion located radially inside the first injection port 14. The region Rg is located lower as it approaches the other circumferential side (-θ side). In this embodiment, the projection area Pa of the first injection port 14 projected onto the outer peripheral surface of the stator core body 32a along the direction D1 is entirely located in the area Rg.

In this specification, the "direction in which the nozzle opens" includes the direction along a normal line that passes through the center of the nozzle and is perpendicular to the center of the nozzle. For example, the two-dot chain line shown as direction D1 in FIG. 5 is a normal line that passes through the center of the first nozzle 14 and is perpendicular to the center of the first nozzle 14.

According to this embodiment, the direction D1 in which the first injection port 14 opens is inclined toward one side in the circumferential direction from the direction facing directly downward in the vertical direction, and is directed toward a portion of the outer peripheral surface of the stator core body 32a that is located on the other side in the circumferential direction from the boundary BP with the end portion on the other side in the circumferential direction of the upper fixed portion 32f. By opening the first injection port 14 in a direction inclined toward one side in the circumferential direction from the direction facing directly downward in the vertical direction, as shown in FIG. 8, the oil O1 injected from the first injection port 14 can be made to flow easily toward one side in the circumferential direction along the outer peripheral surface of the stator core 32. Therefore, the oil O1 injected from the first injection port 14 can easily overcome the upper fixed portion 32f located on one side in the circumferential direction of the first injection port 14.

On the other hand, the first injection port 14 opens toward a portion of the outer peripheral surface of the stator core body 32a that is located on the other circumferential side of the boundary BP. Therefore, compared to when the first injection port 14 opens toward the upper fixed portion 32f, it is difficult for the oil O1 injected from the first injection port 14 to overcome the upper fixed portion 32f. Also, because the first injection port 14 is located below the upper end of the upper fixed portion 32f, it is difficult for the oil O1 injected from the first injection port 14 to overcome the upper fixed portion 32f.

As described above, by determining the position of the first jet nozzle 14 and the opening direction D1 of the first jet nozzle 14 relative to the upper fixed portion 32f, it is possible to prevent all of the oil O1 injected from the first jet nozzle 14 from climbing over the upper fixed portion 32f, while also preventing all of the oil O1 injected from the first jet nozzle 14 from climbing over the upper fixed portion 32f. This makes it easier to branch the oil O1 injected from the first jet nozzle 14 into oil O1a that climbs over the upper fixed portion 32f and oil O1b that does not climb over the upper fixed portion 32f.

Oil O1a that overcomes the upper fixing portion 32f overcomes the upper fixing portion 32f on one side in the circumferential direction and flows forward and downward along the outer circumferential surface of the front part of the stator core main body 32a. Oil O1b that does not overcome the upper fixing portion 32f reverses its flow direction, i.e., toward the other side in the circumferential direction, midway along the other circumferential surface of the upper fixing portion 32f, and flows rearward and downward along the outer circumferential surface of the rear part of the stator core main body 32a. This allows oil O to flow favorably from the upper part of the stator core 32 to both sides in the circumferential direction along the outer circumferential surface of the stator core main body 32a. Therefore, the first refrigerant injection unit 11 makes it easier to supply oil O to the entire stator core 32, improving the cooling efficiency of the stator core 32.

As shown in FIG. 9, when the oil O1b that does not climb over the upper fixing portion 32f turns back to the other side in the circumferential direction halfway along the other circumferential surface of the upper fixing portion 32f, it branches into oil O1b that flows to the right (+Y side) of the first injection nozzle 14 and oil O1b that flows to the left (-Y side) of the first injection nozzle 14.

In addition, according to this embodiment, the direction D1 in which the first injection port 14 opens is tilted toward one side in the circumferential direction with respect to the direction toward the motor shaft J1. This makes it easier for the oil O1 injected from the first injection port 14 to flow toward one side in the circumferential direction along the outer circumferential surface of the stator core 32. This allows a larger amount of oil O1a to overcome the upper fixed portion 32f.

According to this embodiment, the radial distance L2 between the upper fixing portion 32f and the inner peripheral surface of the motor housing portion 61 is smaller than the radial distance L1 between the boundary BP and the inner peripheral surface of the motor housing portion 61 in at least a part. Therefore, the gap between the upper fixing portion 32f and the inner peripheral surface of the motor housing portion 61 is relatively narrow. This makes it possible to limit the amount of oil O1a that can overcome the upper fixing portion 32f through the gap between the upper fixing portion 32f and the inner peripheral surface of the motor housing portion 61. Therefore, it is possible to prevent the amount of oil O1a that overcomes the upper fixing portion 32f from becoming too large. On the other hand, the oil O1 that cannot pass through the gap between the upper fixing portion 32f and the inner peripheral surface of the motor housing portion 61 becomes oil O1b that cannot overcome the upper fixing portion 32f and flows to the other side in the circumferential direction. This makes it possible to increase the amount of oil O1b that does not overcome the upper fixing portion 32f. Therefore, it is easy to equalize the amount of oil O that flows from the upper part of the stator core 32 to both sides in the circumferential direction.

In addition, according to this embodiment, the surface on the other circumferential side of the upper fixing portion 32f is positioned lower as it approaches the other circumferential side. Therefore, the oil O1b that does not climb over the upper fixing portion 32f can be easily caused to flow to the other circumferential side along the surface on the other circumferential side of the upper fixing portion 32f. This makes it possible to prevent the oil O1b that does not climb over the upper fixing portion 32f from accumulating in the upper part of the stator core 32, and allows the oil O1b to be preferably supplied to the outer peripheral surface on the rear side of the stator core main body 32a. Therefore, the cooling efficiency of the stator core 32 can be further improved.

In addition, according to this embodiment, the portion of the outer peripheral surface of the stator core body 32a located radially inward of the first injection port 14 from the boundary BP, i.e., the portion between the boundary BP and the intersection point IP, is located downward as it moves toward the other circumferential side. Therefore, the oil O1b that flows along the other circumferential side surface of the upper fixing part 32f to the outer peripheral surface of the stator core body 32a can be made to flow along the outer peripheral surface of the stator core body 32a to the other circumferential side by utilizing gravity. This makes it possible to further prevent the oil O1b from accumulating in the upper part of the stator core 32, and to more suitably supply the oil O1b to the outer peripheral surface on the rear side of the stator core body 32a. Therefore, the cooling efficiency of the stator core 32 can be further improved.

In addition, according to this embodiment, the surface on the other circumferential side of the upper fixing portion 32f is curved and smoothly connects to the outer peripheral surface of the stator core body 32a at the boundary BP. Therefore, the oil O1b that changes direction to the other circumferential side midway along the surface on the other circumferential side of the upper fixing portion 32f and flows can be smoothly flowed from the surface on the other circumferential side of the upper fixing portion 32f to the outer peripheral surface of the stator core body 32a. This makes it easier for the oil O1b that does not go over the upper fixing portion 32f to flow to the other circumferential side. Therefore, the cooling efficiency of the stator core 32 can be further improved.

In this embodiment, the surface through which the oil O1b flows from the surface on the other circumferential side of the upper fixing portion 32f toward the other circumferential side until it reaches a portion of the outer peripheral surface of the stator core body 32a that is located on the other circumferential side of the first refrigerant injection portion 11 is a curved surface that extends smoothly toward the other circumferential side and is positioned lower as it approaches the other circumferential side. Therefore, the oil O1b that has been redirected toward the other circumferential side on the surface on the other circumferential side of the upper fixing portion 32f can be made to flow favorably toward the other circumferential side by utilizing gravity.

In addition, according to this embodiment, the upper end of the upper fixing portion 32f is located on one side of the vertex VP of the upper side of the stator core body 32a in the circumferential direction, and the first injection port 14 is located on the other side of the vertex VP in the circumferential direction. Therefore, as in this embodiment, it is easy to adopt a configuration in which the surface through which the oil O1b flows from the surface on the other side of the circumferential direction of the upper fixing portion 32f toward the other side of the circumferential direction until it reaches a portion of the outer circumferential surface of the stator core body 32a that is located on the other side of the circumferential direction than the first refrigerant injection portion 11 is a surface that is located lower as it moves toward the other side of the circumferential direction.

In addition, according to this embodiment, the first support portion 63 located on the other circumferential side of the first refrigerant injection portion 11 has a first through groove 63a that penetrates the first support portion 63 in the circumferential direction. Therefore, the oil O1b that has flowed to the other circumferential side of the first refrigerant injection portion 11 can flow to the other circumferential side of the first support portion 63 via the first through groove 63a. This makes it easier for the oil O1b to flow to the other circumferential side, making it easier to supply the oil O to the entire circumference of the stator core 32. Therefore, the cooling efficiency of the stator core 32 can be further improved. In addition, since the outer peripheral surface of the stator core main body 32a can be supported by the first support portion 63, vibration of the stator core 32 can be suppressed.

In addition, according to this embodiment, the first refrigerant injection part 11 is a pipe. Therefore, the first refrigerant injection part 11 can be made more easily than, for example, making a hole in the wall of the housing 6 to make the first refrigerant injection part 11. In addition, the first refrigerant injection part 11 can be easily removed from the housing 6 and replaced.

In addition, according to this embodiment, the nozzles of the first refrigerant injection unit 11 among the nozzles that inject refrigerant into the stator core 32 include only the first injection nozzle 14 that opens in a direction tilted toward one side in the circumferential direction from a direction facing directly downward in the vertical direction. Therefore, it is easier to reduce the number of openings provided in the first refrigerant injection unit 11 compared to a case in which the first refrigerant injection unit 11 is provided with a nozzle that opens in a direction tilted toward the other side in the circumferential direction from a direction facing directly downward in the vertical direction. This makes it possible to suppress a decrease in the pressure of the oil O in the first refrigerant injection unit 11. Therefore, it is possible to suppress a decrease in the momentum of the oil O1 injected from the first injection nozzle 14 of the first refrigerant injection unit 11. Therefore, it is easy to make a part of the oil O1 injected from the first injection nozzle 14 preferably overcome the upper fixing portion 32f.

2 and 4, the second refrigerant injection part 12 is located on the front side (+X side) of the stator 30. The second refrigerant injection part 12 is located lower and forward of the first refrigerant injection part 11. In this embodiment, the radial position of the second refrigerant injection part 12 is the same as the radial position of the fixed part 32b. The second refrigerant injection part 12 is located above the front fixed part 32h. The second refrigerant injection part 12 is located on one circumferential side of the first refrigerant injection part 11. The upper fixed part 32f is located between the first refrigerant injection part 11 and the second refrigerant injection part 12 in the circumferential direction. That is, the first refrigerant injection part 11 and the second refrigerant injection part 12 are arranged in the circumferential direction with the fixed part 32b in between.

As shown in FIG. 4, the second refrigerant injection part 12 has a second pipe body part 12a and a small diameter part 12b provided at the left end (+Y side) of the second pipe body part 12a. Although not shown, the second refrigerant injection part 12 has a small diameter part provided at the right end (-Y side) of the second pipe body part 12a, similar to the first refrigerant injection part 11.

The small diameter portion 12b is the left end (+Y side) of the second refrigerant injection portion 12. The outer diameter of the small diameter portion 12b is smaller than the outer diameter of the second pipe body portion 12a. The second refrigerant injection portion 12 is fixed to the partition wall 61c by inserting the small diameter portion 12b into the partition wall 61c from the right side (-Y side). The small diameter portion 12b opens to the left side. As shown in FIG. 6, the small diameter portion 12b opens to the front end (+X side) of the second branch portion 94f. As a result, the second refrigerant injection portion 12 is connected to the fourth flow path 94. Therefore, the first refrigerant injection portion 11 and the second refrigerant injection portion 12 are connected to each other via the fourth flow path 94. More specifically, the first refrigerant injection portion 11 and the second refrigerant injection portion 12 are connected to each other via the first branch portion 94c, the connection portion 94b, and the second branch portion 94f.

As shown in FIG. 4, a mounting member 17 is provided on the right end (-Y side) of the second refrigerant injection part 12. The mounting member 17 is a rectangular plate with a plate surface facing the axial direction. The right end of the second refrigerant injection part 12 is fixed to the mounting member 17 in the same manner as the first refrigerant injection part 11. The right end of the second refrigerant injection part 12 is blocked by the mounting member 17. Although not shown, the mounting member 17 is fixed to the protruding part 61e shown in FIG. 2 with a bolt. As a result, the right end of the second refrigerant injection part 12 is fixed to the motor housing part 61 via the mounting member 17. The protruding part 61e protrudes radially inward from the inner circumferential surface of the motor housing part 61.

As shown in FIG. 4, the second refrigerant injection unit 12 has a second injection port 15. The second injection port 15 is an injection port that injects oil O into the stator core 32. That is, the injection port of the second refrigerant injection unit 12 includes the second injection port 15. The second injection port 15 is provided on the outer surface of the second refrigerant injection unit 12. The second injection port 15 is, for example, circular. Oil O that has flowed into the second refrigerant injection unit 12 is discharged from the second injection port 15. As shown in FIG. 2, the second injection port 15 is an opening that opens to the outer peripheral surface of the second refrigerant injection unit 12, among the openings of the hole 12d that penetrates the wall portion of the second refrigerant injection unit 12 from the inner peripheral surface to the outer peripheral surface.

As shown in FIG. 4, the second injection port 15 is provided in a portion of the second refrigerant injection portion 12 that overlaps with the stator core 32 when viewed from the radial outside. In this embodiment, six second injection ports 15 are provided in the second pipe main body portion 12a at intervals in the axial direction. As shown in FIG. 2, the second injection port 15 is located on one circumferential side of the upper fixing portion 32f. The second injection port 15 is located on the front side (+X side) of the stator core 32. In this embodiment, the second injection port 15 is located below the upper end of the stator core 32. In this embodiment, the upper end of the stator core 32 is, for example, the upper end of the upper fixing portion 32f. In this embodiment, the second injection port 15 is located below the upper end of the stator core main body 32a and above the motor shaft J1.

The second jet nozzle 15 opens to the other circumferential side at a position on one circumferential side of the upper fixed portion 32f. In this specification, "the jet nozzle opens to a certain side" means that the direction in which the jet nozzle opens includes a component toward a certain side. In other words, "the second jet nozzle 15 opens to the other circumferential side" means that the direction in which the second jet nozzle 15 opens includes a component toward the other circumferential side, and the second jet nozzle 15 may open in a direction perpendicular to the radial direction, or may open at an angle relative to the direction perpendicular to the radial direction. The second jet nozzle 15 opens at an angle radially inward relative to the direction perpendicular to the radial direction. The second jet nozzle 15 opens, for example, diagonally rearward on the upper side.

The second support portion 64 is located between the upper fixing portion 32f and the second refrigerant injection portion 12 in the circumferential direction. The second injection port 15 opens, for example, toward the second through groove 64a provided in the second support portion 64. The oil O2 injected from the second injection port 15 flies diagonally backward on the upper side and reaches the outer peripheral surface of the upper part of the stator core 32 through the second through groove 64a. The oil O2 injected from the second refrigerant injection portion 12 may reach the upper fixing portion 32f, or may not reach the upper fixing portion 32f. The oil O2 that reaches the outer peripheral surface of the upper part of the stator core 32 is blocked by the upper fixing portion 32f, for example, and flows on the outer peripheral surface of the stator core body 32a in a direction almost opposite to the direction of injection. As described above, the front part of the stator core 32 can be cooled by the oil O2 injected from the second injection port 15. Therefore, by providing the second injection port 15, the stator core 32 can be cooled more effectively.

In addition, according to this embodiment, the support portion 65 includes a second support portion 64 located circumferentially between the upper fixed portion 32f and the second refrigerant injection portion 12. Therefore, there is a risk that the oil O1a injected from the first injection port 14 and passing over the upper fixed portion 32f is blocked by the second support portion 64 and is less likely to flow to one side of the second support portion 64 in the circumferential direction. Even in this case, the oil O2 can be injected from the second injection port 15 of the second refrigerant injection portion 12 to supply the oil O2 to the outer peripheral surface of the stator core body 32a located on one side of the second support portion 64 in the circumferential direction.

In addition, according to this embodiment, the second support portion 64 has a second through groove 64a that penetrates the second support portion 64 in the circumferential direction. Therefore, the oil O1a that is injected from the first injection port 14 and passes over the upper fixed portion 32f can flow to one side in the circumferential direction from the second support portion 64 through the second through groove 64a. Also, as described above, the oil O2 injected from the second injection port 15 can be sent to the other side in the circumferential direction from the second support portion 64 through the second through groove 64a. As a result, the oil O injected from the first injection port 14 and the second injection port 15 can be supplied to the outer peripheral surface of the stator core 32 over a wider area. Therefore, the cooling efficiency of the stator core 32 can be further improved.

In addition, according to this embodiment, the second refrigerant injection part 12 is a pipe. Therefore, the second refrigerant injection part 12 can be made more easily than, for example, making a hole in the wall of the housing 6. In addition, the second refrigerant injection part 12 can be easily removed from the housing 6 and replaced.

The oil pump 96 shown in FIG. 1 is a pump that sends oil O as a refrigerant. In this embodiment, the oil pump 96 is an electric pump that is driven by electricity. The oil pump 96 sucks up oil O from the oil reservoir P through the first flow path 92a, and supplies the oil O to the motor 2 through the second flow path 92b, the cooler 97, the third flow path 92c, the fourth flow path 94, and the refrigerant injection unit 10. That is, the oil pump 96 sends the oil O contained inside the housing 6 to the fourth flow path 94, the first refrigerant injection unit 11, and the second refrigerant injection unit 12. Therefore, the oil O can be easily sent to the first refrigerant injection unit 11 and the second refrigerant injection unit 12.

The oil O sent to the third flow path 92c by the oil pump 96 flows into the fourth flow path 94 from the inlet 94a. As shown in FIG. 6, the oil O that flows into the inlet 94a flows to the rear side (-X side) and branches into the first branch 94c and the second branch 94f. The oil O that flows into the first branch 94c flows into the first refrigerant injection part 11 from the left end (+Y side) of the first refrigerant injection part 11. The oil O that flows into the first refrigerant injection part 11 flows to the right side (-Y side) inside the first refrigerant injection part 11 and is supplied to the stator 30 from the supply port 13 and the first injection port 14. On the other hand, the oil O that flows into the second branch 94f flows into the second refrigerant injection part 12 from the left end of the second refrigerant injection part 12. The oil O that flows into the second refrigerant injection section 12 flows to the right within the second refrigerant injection section 12 and is supplied to the stator 30 from the second injection port 15.

In this way, the oil O can be supplied from the first refrigerant injection unit 11 and the second refrigerant injection unit 12 to the stator 30, and the stator 30 can be cooled. In addition, the oil O that flows into the inlet 94a can be branched into the first branching unit 94c and the second branching unit 94f and supplied to the first refrigerant injection unit 11 and the second refrigerant injection unit 12, respectively. Therefore, compared to the case where the oil O flows from one of the refrigerant injection units 10 of the first refrigerant injection unit 11 and the second refrigerant injection unit 12 to the other refrigerant injection unit 10, it is easier to suppress the occurrence of bias in the amount of oil O supplied to the first refrigerant injection unit 11 and the amount of oil O supplied to the second refrigerant injection unit 12. In addition, since the paths until the oil O is supplied to each refrigerant injection unit 10 are both easily shortened, it is easy to maintain the temperature of the oil O supplied to the stator 30 relatively low. Therefore, it is easy to preferably cool the stator 30.

Oil O supplied to the stator 30 from the first refrigerant injection unit 11 and the second refrigerant injection unit 12 drips downward and accumulates in the lower area of the motor housing unit 61. The oil O that accumulates in the lower area of the motor housing unit 61 moves to the oil reservoir P of the gear housing unit 62 through the partition opening 68 provided in the partition 61c. In this way, the second oil passage 92 supplies oil O to the stator 30.

The cooler 97 shown in FIG. 1 cools the oil O passing through the second oil passage 92. The second flow path 92b and the third flow path 92c are connected to the cooler 97. The second flow path 92b and the third flow path 92c are connected via an internal flow path of the cooler 97. The cooler 97 is connected to a cooling water pipe 98 that passes cooling water cooled by a radiator (not shown). The oil O passing through the inside of the cooler 97 is cooled by heat exchange with the cooling water passing through the cooling water pipe 98.

According to this embodiment, the first refrigerant injection unit 11 and the second refrigerant injection unit 12 are connected by the fourth flow path 94. Therefore, for example, by sending oil O to the inlet portion 94a of the fourth flow path 94 as in this embodiment, it is possible to supply oil O to both the first refrigerant injection unit 11 and the second refrigerant injection unit 12. In other words, the number of oil paths provided in the housing 6 can be reduced compared to the case where separate oil paths are provided to supply oil O to each of the first refrigerant injection unit 11 and the second refrigerant injection unit 12. Therefore, it is possible to prevent the housing 6 from becoming large.

The fourth flow passage 94 is provided in the partition wall 61c located on the left side of the stator 30. Therefore, the fourth flow passage 94 can be arranged at a position overlapping with the stator 30 in the axial direction. This makes it easier to arrange the fourth flow passage 94 while avoiding interference with the fixed portion 32b of the stator 30. In addition, compared to, for example, a case in which the fourth flow passage 94 is provided on the radial outside of the stator 30, the housing 6 can be prevented from becoming large in the radial direction. In addition, since the fourth flow passage 94 is provided in the partition wall 61c of the housing 6, the entire drive unit 1 can be made smaller than a case in which a flow passage connecting the first refrigerant injection unit 11 and the second refrigerant injection unit 12 is provided on the outside of the housing 6 by piping or the like. Therefore, according to this embodiment, the drive unit 1 can be prevented from becoming large.

In addition, according to this embodiment, the fourth flow passage 94 has a portion that passes radially inward from the fixed portion 32b. This makes it easier to arrange the fourth flow passage 94 to avoid the fixed portion 32b, and also makes it possible to prevent the housing 6 from becoming large in the radial direction. This makes it possible to further prevent the drive unit 1 from becoming large.

In addition, according to this embodiment, the first refrigerant injection unit 11 and the second refrigerant injection unit 12 are arranged in the circumferential direction with the fixed portion 32b in between. Therefore, the first refrigerant injection unit 11 and the second refrigerant injection unit 12 can be arranged in a position that does not interfere with the fixed portion 32b, and the first refrigerant injection unit 11 and the second refrigerant injection unit 12 can be arranged radially close to the stator core body 32a. This makes it easier to supply oil O from the first refrigerant injection unit 11 and the second refrigerant injection unit 12 to the stator 30, and prevents the drive unit 1 from becoming too large in the radial direction.

In addition, according to this embodiment, the first refrigerant injection unit 11 and the second refrigerant injection unit 12 extend linearly in the axial direction. Therefore, compared to a case where the first refrigerant injection unit 11 and the second refrigerant injection unit 12 extend radially while bending, the drive unit 1 can be prevented from becoming large in the radial direction. In addition, since the shape of the first refrigerant injection unit 11 and the shape of the second refrigerant injection unit 12 can be made simple, the first refrigerant injection unit 11 and the second refrigerant injection unit 12 are easy to manufacture. In addition, the first refrigerant injection unit 11 and the second refrigerant injection unit 12 are easy to arrange facing the stator 30 over a wide range in the axial direction. Therefore, it is easy to supply oil O from the first refrigerant injection unit 11 and the second refrigerant injection unit 12 to a wide range in the axial direction of the stator 30. Therefore, the stator 30 can be more effectively cooled.

In addition, according to this embodiment, the motor shaft J1 extends in a horizontal direction perpendicular to the vertical direction. Therefore, by supplying oil O from the refrigerant injection unit 10 to the upper side of the stator 30, the oil O can be made to flow from the upper side to the lower side of the stator 30 by utilizing gravity. This makes it easy to supply oil O to the entire stator 30, and makes it easy to cool the entire stator 30 with the oil O.

In addition, according to this embodiment, the right end of the first refrigerant injection unit 11 is blocked by the mounting member 16, and the right end of the second refrigerant injection unit 12 is blocked by the mounting member 17. In this embodiment, the right end of the first refrigerant injection unit 11 is the end opposite to the side where oil O flows into the first refrigerant injection unit 11. The right end of the second refrigerant injection unit 12 is the end opposite to the side where oil O flows into the second refrigerant injection unit 12. That is, among the axial ends of each pipe, the end opposite to the side where oil O flows in is blocked. Therefore, it is easier to increase the pressure of the oil O flowing in each pipe compared to when the axial ends of each pipe opposite to the side where oil O flows in are open. This makes it easier to forcefully spray oil O from the oil supply port of each pipe. Therefore, it is easier to suitably supply oil O discharged from each oil supply port to the stator 30.

In particular, in the second refrigerant injection unit 12 of this embodiment, the second injection port 15 faces upward. Therefore, the oil O2 can be injected upward from the second injection port 15 with force. This makes it easier for the oil O2 ejected from the second injection port 15 to reach the upper part of the stator core 32. Therefore, the oil O2 ejected from the second refrigerant injection unit 12 can be easily supplied over a wide area of the stator core 32, and the stator core 32 can be cooled more effectively.

Second Embodiment
As shown in Fig. 10, the nozzle of the first refrigerant jet unit 111 of this embodiment includes a third jet port 119. The third jet port 119 is, for example, an opening of a hole 111e that penetrates the wall of the first refrigerant jet unit 111 from the inner peripheral surface to the outer peripheral surface, the opening opening being on the outer peripheral surface of the first refrigerant jet unit 111. The third jet port 119 opens on the other circumferential side. The third jet port 119 opens on the opposite side to the first jet port 14 in the circumferential direction. The third jet port 119 opens, for example, diagonally backward on the lower side. The opening direction of the third jet port 119 is inclined radially inward from the direction perpendicular to the radial direction.

Although not shown in the figures, in this embodiment, the third jet nozzles 119 are provided in a plurality of locations spaced apart in the axial direction. For example, two each of the first jet nozzles 14 and the third jet nozzles 119 are provided. The axial position of each third jet nozzle 119 is, for example, the same as the axial position of each first jet nozzle 14. For example, the first jet nozzle 14 and the third jet nozzle 119 are arranged line-symmetrically with respect to the imaginary line IL3 when viewed in the axial direction. For example, the opening area of the first jet nozzle 14 and the opening area of the third jet nozzle 119 are the same as each other. Note that the opening area of the third jet nozzle 119 may be larger than the opening area of the first jet nozzle 14 or may be smaller than the opening area of the first jet nozzle 14.

Oil O3 injected from the third injection port 119 is injected toward the other circumferential side. Therefore, oil O can be more effectively supplied to the portion of the stator core 32 that is located on the other circumferential side of the first refrigerant injection unit 111. This allows the stator core 32 to be more effectively cooled. The other configurations of the first refrigerant injection unit 111 can be the same as the other configurations of the first refrigerant injection unit 11 of the first embodiment.

Third Embodiment
As shown in FIG. 11, in the stator core 232 of this embodiment, the upper fixing portion 232f is located on one circumferential side of the upper fixing portion 32f of the first embodiment described above. The upper fixing portion 232f protrudes obliquely forward upward. The first refrigerant injection portion 211 is located on the other circumferential side of the upper fixing portion 232f. The first refrigerant injection portion 211 is located forward of the motor shaft J1. The first refrigerant injection portion 211 is located on the upper side of the stator core main body 32a. In this embodiment, the opening direction of the first injection port 214 of the first refrigerant injection portion 211 is a direction facing directly downward in the vertical direction, and also a direction facing a portion of the outer circumferential surface of the stator core main body 32a that is located on the other circumferential side of the boundary with the end portion on the other circumferential side of the upper fixing portion 232f. Therefore, compared to a case where the first injection port 214 opens at an angle to the other circumferential side rather than directly below in the vertical direction, the oil O injected from the first injection port 214 is more likely to flow to one circumferential side. As a result, similar to the first embodiment described above, the oil O injected from the first injection port 214 is more likely to be divided into the oil O that goes over the upper fixing portion 232f and the oil O that does not go over the upper fixing portion 232f. This allows the stator core 232 to be cooled appropriately. Therefore, the cooling efficiency of the stator core 232 can be improved.

The opening direction of the first injection port 214 of the first refrigerant injection unit 211 is tilted toward one circumferential side with respect to the direction toward the motor shaft J1. Therefore, the oil O injected from the first injection port 214 is more likely to flow toward one circumferential side. The other configurations of the first refrigerant injection unit 211 can be the same as the other configurations of the first refrigerant injection unit 11 of the first embodiment. The other configurations of the drive device 201 can be the same as the other configurations of the drive device 1 of the first embodiment.

The present invention is not limited to the above-described embodiment, and other configurations may be adopted within the scope of the technical concept of the present invention. In the above-described embodiment, the refrigerant is oil O, but this is not limited to the above. The refrigerant is not particularly limited as long as it can be supplied to the stator to cool the stator. The refrigerant may be, for example, an insulating liquid or water. If the refrigerant is water, an insulating treatment may be applied to the surface of the stator.

When the first refrigerant injection section and the second refrigerant injection section are pipes, each pipe may be a polygonal pipe. The first refrigerant injection section and the second refrigerant injection section do not have to be pipes. The first refrigerant injection section and the second refrigerant injection section may be oil passages provided in the housing. The first refrigerant injection section may not include a supply port for supplying refrigerant to the coil end. The second refrigerant injection section may not be provided. A plurality of first injection ports may be provided at the same axial position. Only one first injection port may be provided. The direction in which the first injection port opens is inclined to one circumferential side with respect to the direction facing the motor shaft, and the direction in which the first injection port opens is directed to a portion of the outer circumferential surface of the stator core body that is located on the other circumferential side of the boundary with the end of the upper fixed part on the other circumferential side, so long as the direction in which the first injection port opens is inclined to one circumferential side with respect to the direction facing the motor shaft, and is directed to a portion of the outer circumferential surface of the stator core body that is located on the other circumferential side of the boundary with the end of the upper fixed part on the other circumferential side, so long as the direction in which the first injection port opens is inclined to one circumferential side with respect to the direction facing the motor shaft, the vertical direction is not particularly limited. The direction in which the first injection port opens may be directed upward, for example.

The shape of the fixing portion of the stator core is not particularly limited. The entire upper fixing portion may be located on one circumferential side of the upper apex of the stator core body, or on the other circumferential side of the upper apex of the stator core body. The radial distance between the upper fixing portion and the inner circumferential surface of the motor housing portion may be smaller than the radial distance between the boundary with the other circumferential end of the upper fixing portion and the inner circumferential surface of the motor housing portion only in part. The radial distance between the upper fixing portion and the inner circumferential surface of the motor housing portion may be larger than the radial distance between the boundary with the other circumferential end of the upper fixing portion and the inner circumferential surface of the motor housing portion.

The upper fixing portion may be provided at the portion of the stator core that is located at the top in the vertical direction. In this case, the upper fixing portion may protrude directly upward in the vertical direction. In this case, the first refrigerant injection portion and the third refrigerant injection portion different from the first refrigerant injection portion may be located at the top of the stator core in the vertical direction and may be arranged to sandwich the upper fixing portion in the circumferential direction. The third refrigerant injection portion has an injection port that injects oil O into the stator core. In this case, the first refrigerant injection portion and the third refrigerant injection portion may be arranged symmetrically with respect to a virtual line that passes through the motor shaft and extends vertically when viewed in the axial direction of the motor shaft. In this case, the direction in which the first injection port of the first refrigerant injection portion opens and the direction in which the injection port of the third refrigerant injection portion opens may be directed vertically downward. The opening area of the injection port of the third refrigerant injection portion may be the same as or different from the opening area of the first injection port.

The first support portion may not have a first through groove. The second support portion may not have a second through groove. The support portion may not include one of the first support portion and the second support portion. The support portion may not be provided.

The drive device is not particularly limited as long as it is a device that can move a target object using a motor as a power source. The drive device does not need to have a transmission mechanism. The torque of the motor may be output directly to the target from the motor shaft. In this case, the drive device corresponds to the motor itself. The direction in which the motor shaft extends is not particularly limited as long as it is a direction that intersects with the vertical direction. In this specification, "the motor shaft extends in a horizontal direction perpendicular to the vertical direction" includes the case in which the motor shaft extends in a strictly horizontal direction, as well as the case in which the motor shaft extends in a substantially horizontal direction. In other words, in this specification, "the motor shaft extends in a horizontal direction perpendicular to the vertical direction" may mean that the motor shaft is slightly inclined with respect to the horizontal direction. In the above embodiment, the case in which the drive device does not include an inverter unit has been described, but this is not limited to this. The drive device may include an inverter unit. In other words, the drive device may be integral with the inverter unit.

The use of the drive unit is not particularly limited. The drive unit does not have to be mounted on a vehicle. The configurations described in this specification can be combined as appropriate within the scope of not being mutually inconsistent.

1,201...drive unit, 2...motor, 6...housing, 10...refrigerant injection unit, 11,111,211...first refrigerant injection unit, 12...second refrigerant injection unit, 13...supply port, 14,214...first injection port (injection port), 15...second injection port (injection port), 20...rotor, 30...stator, 31...coil, 32,232...stator core, 32a...stator core body, 32b...fixed portion, 32f,232f...upper fixed portion, 33...coil assembly, 33a,33b...coil end, 61...motor housing, 63...first support portion, 63a...first through groove, 64...second support portion, 64a...second through groove, 65...support portion, 119...third injection port, BP...boundary, J1...motor shaft, O...oil (refrigerant), VP...vertex

Claims (17)

A drive device that can be mounted on a vehicle,
a motor including a rotor rotatable about a motor shaft extending in a direction intersecting a vertical direction, and a stator core positioned radially outward of the rotor;
a housing that accommodates the motor therein;
a first refrigerant injection unit having an injection port for injecting a refrigerant into the stator core;
an electric pump that supplies the refrigerant to the motor via the first refrigerant injection portion;
Equipped with
The stator core is
A cylindrical stator core body whose outer circumferential surface surrounds the rotor;
a fixing portion that protrudes radially outward from the stator core body and is fixed to the housing;
having
The fixing portion includes an upper fixing portion protruding upward from the stator core body,
the injection port includes a first injection port located below an upper end of the upper fixing portion,
the upper fixing portion is located on one circumferential side of the first injection port,
an opening direction of the first injection port is a direction facing directly downward or a direction inclined toward one circumferential side from a direction facing directly downward, and is a direction facing a portion of an outer circumferential surface of the stator core body that is located on the other circumferential side of a boundary with an end portion of the upper fixed portion on the other circumferential side,
a portion of the outer circumferential surface of the stator core body between the boundary and a portion located radially inward of the first injection port is located lower toward the other circumferential side,
When the drive device operates to cause the vehicle to travel steadily, the electric pump drives in accordance with the operation of the drive device, so that the refrigerant sprayed from the first injection port branches into refrigerant that passes over the upper fixed portion and flows circumferentially along the outer peripheral surface of the stator core body to one side, and refrigerant that does not pass over the upper fixed portion and flows circumferentially along the outer peripheral surface of the stator core body to the other side. The drive device according to claim 1, wherein the first injection port is opened in a direction inclined toward one side in the circumferential direction with respect to the direction toward the motor shaft. A drive device that can be mounted on a vehicle,
a motor including a rotor rotatable about a motor shaft extending in a direction intersecting a vertical direction, and a stator core positioned radially outward of the rotor;
a housing that accommodates the motor therein;
a first refrigerant injection unit having an injection port for injecting a refrigerant into the stator core;
an electric pump that supplies the refrigerant to the motor via the first refrigerant injection portion;
Equipped with
The stator core is
A cylindrical stator core body whose outer circumferential surface surrounds the rotor;
a fixing portion that protrudes radially outward from the stator core body and is fixed to the housing;
having
The fixing portion includes an upper fixing portion protruding upward from the stator core body,
the injection port includes a first injection port located below an upper end of the upper fixing portion,
the upper fixing portion is located on one circumferential side of the first injection port,
an opening direction of the first injection port is inclined toward one circumferential side with respect to a direction toward the motor shaft, and is also oriented toward a portion of an outer circumferential surface of the stator core body that is located toward the other circumferential side of a boundary with an end portion of the upper fixed portion on the other circumferential side;
a portion of the outer circumferential surface of the stator core body between the boundary and a portion located radially inward of the first injection port is located lower toward the other circumferential side,
When the drive device operates to cause the vehicle to travel steadily, the electric pump drives in accordance with the operation of the drive device, so that the refrigerant sprayed from the first injection port branches into refrigerant that passes over the upper fixed portion and flows circumferentially along the outer peripheral surface of the stator core body to one side, and refrigerant that does not pass over the upper fixed portion and flows circumferentially along the outer peripheral surface of the stator core body to the other side. the housing has a motor accommodating portion that surrounds the stator core from the radially outer side,
the upper fixing portion is disposed away from an inner circumferential surface of the motor accommodating portion,
A drive device as described in any one of claims 1 to 3, wherein a radial distance between the upper fixed portion and an inner circumferential surface of the motor accommodating portion is smaller, at least in part, than a radial distance between the boundary and the inner circumferential surface of the motor accommodating portion. The drive device according to any one of claims 1 to 4, wherein the surface on the other circumferential side of the upper fixing part is positioned downward as it approaches the other circumferential side. The drive device according to claim 5, wherein the boundary is located on the other circumferential side of the upper apex of the stator core body. The drive device according to any one of claims 1 to 6, wherein the surface on the other circumferential side of the upper fixed part is curved and smoothly connects to the outer circumferential surface of the stator core body at the boundary. an upper end portion of the upper fixing portion is located on one circumferential side of an upper apex of the stator core body,
The drive unit according to claim 1 , wherein the first injection port is located on the other circumferential side of the apex. the housing has a support portion that contacts an outer circumferential surface of the stator core body,
the support portion includes a first support portion located on the other circumferential side of the first refrigerant injection portion,
The drive device according to claim 1 , wherein the first support portion has a first through groove that penetrates the first support portion in a circumferential direction. The motor includes a coil assembly having a plurality of coils;
the coil assembly has a coil end protruding from the stator core in the axial direction of the motor shaft,
The drive device according to claim 1 , wherein the first coolant injection portion includes a supply port that supplies coolant to the coil end. The drive device according to any one of claims 1 to 10, wherein the first refrigerant injection part is a pipe extending in the axial direction of the motor shaft. A second refrigerant injection unit having an injection port for injecting refrigerant into the stator core is further provided.
The drive device according to claim 1 , wherein the injection port of the second refrigerant injection portion includes a second injection port that opens to the other circumferential side at a position on one circumferential side of the upper fixed portion. the housing has a support portion that contacts an outer circumferential surface of the stator core body,
The drive device according to claim 12 , wherein the support portion includes a second support portion located circumferentially between the upper fixed portion and the second refrigerant injection portion. The drive device according to claim 13, wherein the second support portion has a second through groove that penetrates the second support portion in the circumferential direction. The drive device according to any one of claims 12 to 14, wherein the second refrigerant injection part is a pipe extending in the axial direction of the motor shaft. The drive device according to any one of claims 1 to 15, wherein the nozzle of the first refrigerant injection part includes only nozzles that open in a direction inclined toward one side in the circumferential direction rather than facing directly downward. The drive device according to any one of claims 1 to 15, wherein the nozzle of the first refrigerant injection part includes a third nozzle opening on the other circumferential side.

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