Rotor and rotating electrical machine

Abstract

One embodiment of the present invention is a rotor capable of rotating about a central axis, the rotor comprising: a shaft extending in an axial direction; a rotor core fixed to the shaft; and an end plate arranged side by side with the rotor core in the axial direction. The shaft has: a void portion provided inside the shaft; and a through-hole connected to the void portion. The through-hole has a first opening that opens in the outer peripheral surface of the shaft. The end plate has a first groove portion extending in the radial direction. The first groove portion has a second opening portion that opens on the side opposite to the side where the rotor core is located in the axial direction. The radially inner end portion of the first groove portion is connected to the first opening portion. The inner surface of the first groove portion has a groove bottom surface located on the side where the rotor core is located in the axial direction. The slot bottom surface has a first surface that is axially separated from the rotor core toward the outside in the radial direction.

Description

Technical Field

[0001] The invention relates to a rotor and a rotating electric machine.

[0002] This application claims priority based on Japanese Patent Application No. 2022-085171 filed in Japan on May 25, 2022, the contents of which are cited here. Background Art

[0003] A rotary electric machine that uses a refrigerant to cool the coil end is known. For example, Patent Document 1 describes a structure in which a discharge passage that can discharge the refrigerant is provided in an end plate, and the refrigerant discharged from the opening of the discharge passage is blown toward the coil end.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2009-81953 Summary of the invention

[0007] Problems to be solved by the invention

[0008] When the discharge passage is provided in the end plate as described above, for example, it may be difficult to blow the refrigerant toward the axial end of the coil end, and the refrigerant discharged from the discharge passage of the end plate may not be sufficiently supplied to the coil end.

[0009] The present invention has been made in view of the above circumstances, and one object thereof is to provide a rotor and a rotating electrical machine having a structure that can easily supply a refrigerant to a coil end portion via an end plate.

[0010] Means for solving problems

[0011] One embodiment of the present invention is a rotor that can rotate around a central axis, wherein the rotor has: a shaft that extends in the axial direction; a rotor core that is fixed to the shaft; and an end plate that is arranged in the axial direction with the rotor core. The shaft has: a gap portion that is provided inside the shaft; and a through hole that is connected to the gap portion. The through hole has a first opening portion that opens on the outer peripheral surface of the shaft. The end plate has a first groove portion that extends in the radial direction. The first groove portion has a second opening portion that opens on the side opposite to the side where the rotor core is located in the axial direction. The radially inner end of the first groove portion is connected to the first opening portion. The inner surface of the first groove portion has a groove bottom surface that is axially located on the side where the rotor core is located. The groove bottom surface has a first surface that moves away from the rotor core in the axial direction as it moves toward the radial outer side.

[0012] One embodiment of the present invention is a rotating electrical machine, comprising: the above-mentioned rotor; and a stator located radially outside the rotor. The stator comprises: a stator core; and a coil end portion protruding axially from the stator core. In a cross section along the axial direction, an imaginary line extending radially outward from the radially outer end portion of the first surface in a direction along the first surface passes through the coil end portion.

[0013] Effects of the Invention

[0014] According to one aspect of the present invention, in the rotating electrical machine, the refrigerant can be easily supplied to the coil end portion via the end plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic configuration diagram schematically showing the driving device in the first embodiment.

[0016] Figure 2 It is a cross-sectional view showing a part of the rotor and the stator in the first embodiment.

[0017] Figure 3 It is a perspective view showing the end plate in the first embodiment.

[0018] Figure 4 This is a diagram of the end plate in the first embodiment as viewed in the axial direction.

[0019] Figure 5 It is a perspective view showing a part of the end plate and a part of the shaft in the first embodiment.

[0020] Figure 6 It is a cross-sectional view showing a part of the rotor and a part of the stator in the first embodiment, and is a diagram showing the flow of oil supplied to the coil end portion via the end plate.

[0021] Figure 7 is a cross-sectional view showing a portion of the rotor and a portion of the stator in the first embodiment, Figure 6 Cross-sectional views at different circumferential positions.

[0022] Figure 8 It is a perspective view showing an end plate in the second embodiment. DETAILED DESCRIPTION

[0023] In the following description, the vertical direction is defined and described based on the positional relationship when the drive device of the embodiment is mounted on a vehicle located on a horizontal road surface. That is, the relative positional relationship about the vertical direction described in the following embodiments only needs to be satisfied when the drive device is mounted on a vehicle located on a horizontal road surface.

[0024] In the accompanying 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 referred to as the "upper side", and the lower side in the vertical direction is referred to as the "lower side". The X-axis direction is a direction perpendicular to the Z-axis direction, and is the front-to-back direction of a vehicle equipped with a drive device. In 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-to-right direction of the vehicle, that is, the vehicle width direction. In 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 left side is one axial side, and the right side is the other axial side. The front-to-back direction and the left-to-right direction are horizontal directions perpendicular to the vertical direction.

[0025] In addition, the positional relationship in the front-rear direction is not limited to the positional relationship in 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. In addition, in this specification, "parallel direction" also includes a substantially parallel direction, and "vertical direction" also includes a substantially vertical direction.

[0026] The center axis J shown in the figure as appropriate is an imaginary axis extending in a direction intersecting the vertical direction. In more detail, the center axis J extends in the Y-axis direction perpendicular to the vertical direction, that is, the left-right direction of the vehicle. In the following description, unless otherwise specified, the direction parallel to the center axis J is referred to as the "axial direction", the radial direction centered on the center axis J is referred to as the "radial direction", and the circumferential direction centered on the center axis J, that is, the direction around the center axis J is referred to as the "circumferential direction".

[0027] <First embodiment>

[0028] Figure 1 The drive device 100 of the present embodiment shown is a drive device mounted on a vehicle and rotates the axle 64. The vehicle equipped with the drive device 100 is a vehicle using a motor as a power source, such as a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHV), or an electric vehicle (EV). Figure 1 As shown, the drive device 100 includes a rotating electric machine 10 and a transmission device 60. The transmission device 60 is connected to the rotating electric machine 10 and transmits the rotation of the rotating electric machine 10, that is, the rotation of the rotor 30 described later, to the axle 64 of the vehicle. The transmission device 60 of this embodiment includes a gear housing 61, a reduction gear 62 connected to the rotating electric machine 10, and a differential device 63 connected to the reduction gear 62.

[0029] The gear housing 61 accommodates the reduction gear 62, the differential gear 63, and the oil O therein. The oil O is stored in the lower area of ​​the gear housing 61. The oil O circulates in the refrigerant flow path 90 described later. The oil O is used as a refrigerant for cooling the rotary electric machine 10. In addition, the oil O is used as a lubricating oil for the reduction gear 62 and the differential gear 63. As the oil O, for example, in order to exert the functions of a refrigerant and a lubricating oil, it is preferable to use an oil equivalent to an automatic transmission lubricating oil (ATF: Automatic Transmission Fluid) with a relatively low viscosity.

[0030] The differential device 63 has a ring gear 63a. The torque output from the rotating electric machine 10 is transmitted to the ring gear 63a via the reduction gear 62. The lower end of the ring gear 63a is immersed in the oil O stored in the gear housing 61. The oil O is lifted up by the rotation of the ring gear 63a. A part of the lifted oil O is provided to the reduction gear 62 and the differential device 63 as lubricating oil, for example. In addition, another part of the lifted oil O is stored in a reservoir 65 arranged in the gear housing 61. The oil O stored in the reservoir 65 flows to the interior of the shaft 31 described later.

[0031] The rotating electric machine 10 is a part that drives the driving device 100. The rotating electric machine 10 is located, for example, on the right side of the transmission device 60. In the present embodiment, the rotating electric machine 10 is a motor. The rotating electric machine 10 includes a motor housing 20, a rotor 30 that can rotate around a central axis J, and a stator 40 that is opposed to the rotor 30 in the radial direction with a gap therebetween.

[0032] The motor housing 20 is a housing that accommodates the rotor 30 and the stator 40. The motor housing 20 is connected to the right side of the gear housing 61. The motor housing 20 has a peripheral wall portion 21, a partition wall portion 22, and a cover portion 23. The peripheral wall portion 21 and the partition wall portion 22 are, for example, parts of the same single component. The cover portion 23 is, for example, separate from the peripheral wall portion 21 and the partition wall portion 22.

[0033] The peripheral wall portion 21 is in the shape of a cylinder that surrounds the central axis J and opens on the right side. The partition wall portion 22 is connected to the left end of the peripheral wall portion 21. The partition wall portion 22 separates the interior of the motor housing 20 from the interior of the gear housing 61 in the axial direction. The partition wall portion 22 has a partition wall opening 22a that connects the interior of the motor housing 20 and the interior of the gear housing 61. The partition wall portion 22 holds a bearing 34. The cover portion 23 is fixed to the right end of the peripheral wall portion 21. The cover portion 23 closes the opening on the right side of the peripheral wall portion 21. The cover portion 23 holds a bearing 35.

[0034] The stator 40 is located radially outside the rotor 30. The stator 40 is fixed inside the motor housing 20. Figure 2As shown, the stator 40 has a stator core 41 and a coil assembly 42. The stator core 41 is in a ring shape surrounding the central axis J of the rotating electrical machine 10. The stator core 41 is located radially outside the rotor 30. The stator core 41 surrounds the rotor 30. The stator core 41 is formed by stacking a plurality of plate members such as electromagnetic steel plates in the axial direction. Although not shown in the figure, the stator core 41 has a cylindrical core back extending in the axial direction and a plurality of teeth extending radially inward from the core back. The plurality of teeth are arranged at equal intervals along the circumferential direction over the entire circumference.

[0035] The coil assembly 42 has a plurality of coils 42c mounted on the stator core 41. Each coil 42c is, for example, composed of a flat wire having a quadrilateral or substantially quadrilateral cross-sectional shape. In addition, each coil 42c may also be, for example, composed of a round wire having a circular cross-sectional shape. The plurality of coils 42c are respectively mounted on the stator core 41 via insulating members 43. The insulating members 43 are, for example, respectively arranged between the circumferential directions of the teeth of the stator core 41. The insulating member 43 is, for example, insulating paper. The insulating member 43 protrudes axially on both sides of the stator core 41. Although not shown in the figure, the coil assembly 42 may have a bundling component for bundling the coils 42c, or may have a lap wire connecting the coils 42c to each other.

[0036] The coil assembly 42 has coil ends 42a and 42b that protrude axially from the stator core 41. The coil end 42a is a portion that protrudes to the right side from the stator core 41. The coil end 42b is a portion that protrudes to the left side from the stator core 41. The coil end 42a includes a portion of each coil 42c included in the coil assembly 42 that protrudes to the right side from the stator core 41. The coil end 42b includes a portion of each coil 42c included in the coil assembly 42 that protrudes to the left side from the stator core 41. In the present embodiment, the coil ends 42a and 42b are annular in shape with the central axis J as the center. Although not shown in the figure, the coil ends 42a and 42b may include a bundling member for bundling the coils 42c, or may include a lap wire that connects the coils 42c to each other. The right end of the coil end 42a is located to the right of the right end of the insulating member 43. The left end of the coil end 42b is located to the left of the left end of the insulating member 43.

[0037] The rotor 30 includes a shaft 31, a rotor core 32, and a magnet 33. The shaft 31 extends in the axial direction. In the present embodiment, the shaft 31 is a cylindrical hollow shaft extending in the axial direction with the central axis J as the center. The interior of the shaft 31 as a hollow shaft is a gap portion 37. That is, the shaft 31 has a gap portion 37 provided inside the shaft 31. The shaft 31 can rotate with the central axis J as the center. Figure 1 As shown, the shaft 31 is rotatably supported by bearings 34 and 35 .

[0038] The shaft 31 extends in a manner spanning the interior of the motor housing 20 and the interior of the gear housing 61. The left end of the shaft 31 protrudes into the interior of the gear housing 61. The reduction device 62 is connected to the left end of the shaft 31. The left end of the shaft 31 is open to the interior of the gear housing 61. That is, the left end of the gap portion 37 is open to the interior of the gear housing 61. The right end of the shaft 31 can be open or closed. That is, the right end of the gap portion 37 can be open or closed. The oil O in the reservoir 65 flows into the gap portion 37 from the left end of the gap portion 37. The oil O that has flowed into the gap portion 37 flows to the right in the gap portion 37.

[0039] like Figure 2 As shown, the shaft 31 has a through hole 31a connected to the gap portion 37. The through hole 31a penetrates a portion of the shaft 31 in the radial direction from the inner circumferential surface of the shaft 31 to the outer circumferential surface of the shaft 31. The through hole 31a is, for example, a circular hole. The through hole 31a has an inner opening portion 31b opened on the inner circumferential surface of the shaft 31 and an outer opening portion 31c opened on the outer circumferential surface of the shaft 31. The inner opening portion 31b opens into the gap portion 37. In this embodiment, the outer opening portion 31c corresponds to the "first opening portion".

[0040] A plurality of through holes 31a are provided at equal intervals in the circumferential direction in the portion of the shaft 31 located on the right side of the rotor core 32 and in the portion of the shaft 31 located on the left side of the rotor core 32. In the present embodiment, four through holes 31a are provided at intervals of 90° in the circumferential direction in the portion of the shaft 31 located on the right side of the rotor core 32 and in the portion of the shaft 31 located on the left side of the rotor core 32, for example.

[0041] like Figure 2 As shown, the shaft 31 is provided with a flange portion 31e protruding radially outward from the outer peripheral surface of the shaft 31. That is, the rotor 30 has the flange portion 31e as a protruding portion protruding radially outward from the outer peripheral surface of the shaft 31. The flange portion 31e is provided on the outer peripheral surface of the portion of the shaft 31 located to the left of the rotor core 32. The flange portion 31e and the shaft 31 are part of the same single component. The flange portion 31e is in the shape of an annulus centered on the central axis J and surrounding the shaft 31. The flange portion 31e is located to the left of the plurality of through holes 31a. The flange portion 31e is located radially inward of the coil end 42b. The left end of the flange portion 31e is located to the right of the left end of the coil end 42b. An end plate 50b described later is sandwiched between the flange portion 31e and the rotor core 32 in the axial direction.

[0042] The shaft 31 is provided with a nut 36. The nut 36 is a protrusion protruding radially outward from the outer circumferential surface of the shaft 31. That is, the rotor 30 has the nut 36 as a protrusion. The nut 36 is separate from the shaft 31. The nut 36 is fixed to the outer circumferential surface of the portion of the shaft 31 located to the right of the rotor core 32. The nut 36 is in the shape of an annulus centered on the central axis J and surrounding the shaft 31. A threaded portion that meshes with a threaded portion provided on the outer circumferential surface of the shaft 31 is provided on the inner circumferential surface of the nut 36. The nut 36 is located to the right of the plurality of through holes 31a. The outer diameter of the nut 36 is larger than the outer diameter of the flange portion 31e. The nut 36 is located radially inward of the coil end 42a. The right end of the nut 36 is arranged in the axial direction at a position substantially the same as the right end of the coil end 42a. An end plate 50a described later is sandwiched between the nut 36 and the rotor core 32 in the axial direction.

[0043] The rotor core 32 is fixed to the shaft 31. The rotor core 32 is cylindrical and surrounds the shaft 31 and extends in the axial direction. The inner circumferential surface of the rotor core 32 is fixed to the outer circumferential surface of the shaft 31. The rotor core 32 is formed by stacking a plurality of plate members such as electromagnetic steel plates in the axial direction. The rotor core 32 has a magnet hole 32a that penetrates the radially outer portion of the rotor core 32 in the axial direction. A plurality of magnet holes 32a are provided at intervals in the circumferential direction.

[0044] The magnet 33 is fixed to the rotor core 32. A plurality of magnets 33 are provided. The plurality of magnets 33 are respectively inserted into the plurality of magnet holes 32a. The plurality of magnets 33 extend in the axial direction. The axial dimension of the magnet 33 is substantially the same as the axial dimension of the rotor core 32.

[0045] The rotor 30 has an end plate 50 arranged in the axial direction with the rotor core 32. In the present embodiment, the end plate 50 includes two end plates, an end plate 50a arranged in the right side of the rotor core 32 and an end plate 50b arranged in the left side of the rotor core 32. The two end plates 50a and 50b are arranged to sandwich the rotor core 32 in the axial direction. The nut 36 is screwed into the shaft 31, and the two end plates 50a and 50b are sandwiched between the nut 36 and the flange portion 31e and fixed to the rotor core 32. In this way, by providing the nut 36 and the flange portion 31e as the protruding portion, the end plates 50a and 50b can be suppressed from being displaced in the axial direction with respect to the rotor core 32.

[0046] The axial ends of the magnet hole 32a are closed by the end plates 50a and 50b, respectively. As a result, the magnet 33 is pressed from both sides of the axial direction by the end plates 50a and 50b, which prevents the magnet 33 from flying out of the magnet hole 32a in the axial direction. The end plates 50a and 50b have the same structure except that they are symmetrically arranged in the axial direction across the rotor core 32. Therefore, in the following description, sometimes only the end plate 50a is used as a representative for description.

[0047] In the description of the end plate 50a, the left side refers to the side where the rotor core 32 is located with respect to the end plate 50a, and the right side refers to the side opposite to the side where the rotor core 32 is located with respect to the end plate 50a. In the description of the end plate 50b, the left side refers to the side opposite to the side where the rotor core 32 is located with respect to the end plate 50b, and the right side refers to the side where the rotor core 32 is located with respect to the end plate 50b.

[0048] like Figure 3 and Figure 4 As shown, the end plate 50a is a plate-shaped component that is annular with the central axis J as the center and has a plate surface facing the axial direction. Figure 2 As shown, the end plate 50a surrounds the shaft 31. The outer diameter of the end plate 50a is substantially the same as the outer diameter of the rotor core 32. The end plate 50a is arranged radially inward of the coil end 42a with a gap therebetween. The left end of the end plate 50a contacts the rotor core 32. The right end of the end plate 50a is located to the left of the right end of the coil end 42a.

[0049] The end plate 50a has an end plate body portion 51 and a wall portion 52. Figure 3 and Figure 4 As shown in FIG. 1 , the end plate body 51 is in the shape of a ring centered on the central axis J, and is in the shape of a plate with the plate surface facing the axial direction. Figure 5 As shown, the shaft 31 is inserted into the inner side of the end plate body 51. The inner edge of the end plate body 51 is fitted with the outer peripheral surface of the shaft 31.

[0050] The wall portion 52 protrudes to the right side (-Y side) from the radially outer portion of the end plate main body portion 51. That is, the wall portion 52 protrudes in a direction away from the rotor core 32 in the axial direction. Figure 2 As shown in FIG. 1 , the right end of the wall portion 52 is located to the left of the right end of the coil end 42a. Figure 3 and Figure 4 As shown, the wall portion 52 extends in the circumferential direction. In the present embodiment, the wall portion 52 is in the shape of an annulus centered on the central axis J. The radially inner edge of the wall portion 52 is arranged radially outwardly away from the inner edge of the end plate main body 51. The radially outer edge of the wall portion 52 is arranged radially inwardly away from the outer edge of the end plate main body 51. The right side surface of the portion of the end plate main body 51 located radially outwardly than the wall portion 52 is an inclined surface 51b located on the left side as it moves radially outward. The cross-sectional shape of the wall portion 52 perpendicular to the circumferential direction is, for example, roughly rectangular.

[0051] By removing a portion of the wall portion 52 by cutting, the circumferential balance correction of the rotor 30 can be performed. That is, the wall portion 52 is a portion for performing the balance correction of the rotor 30 by removing a portion by cutting. Since the portion for balance correction is provided on the end plate 50a in this way, it is not necessary to cut the rotor core 32 when the circumferential balance correction of the rotor 30 is performed, and the reduction in the magnetic characteristics of the rotor 30 can be suppressed. In addition, by providing the wall portion 52 as a portion to be cut, it is possible to ensure a cutting margin for performing the circumferential balance correction of the rotor 30 without increasing the axial dimension of the end plate main body 51. As a result, the circumferential balance correction of the rotor 30 can be appropriately performed, and the enlargement of the rotor 30 in the axial direction can be suppressed. The circumferential balance correction of the rotor 30 is performed, for example, as follows. Figure 3 As shown by the two-dot chain line, this is performed by providing a hole 52a from the right side in the wall portion 52. In addition, the balance correction in the circumferential direction of the rotor 30 may be performed by removing a part of the wall portion 52 in any manner.

[0052] The end plate 50a has a first groove portion 55 extending in the radial direction. The first groove portion 55 is provided on the surface of the end plate 50a on the opposite side to the side where the rotor core 32 is located, that is, on the right side (-Y side). The first groove portion 55 has a groove opening portion 55e as a second opening portion that opens to the opposite side to the side where the rotor core 32 is located in the axial direction, that is, on the right side. In the present embodiment, the first groove portion 55 is provided in a manner that spans the end plate main body portion 51 and the wall portion 52. The first groove portion 55 extends from the inner edge of the end plate main body portion 51 to the radial outside, and extends to a position radially outside of the radially inner edge of the wall portion 52.

[0053] The radially inner end of the first groove portion 55 is located radially inwardly of the radially inner edge of the wall portion 52. The radially inner end of the first groove portion 55 opens radially inwardly. Figure 5 As shown in FIG. 1 , the radially inner end of the first groove portion 55 is radially opposed to the outer opening portion 31c and the peripheral edge of the portion of the outer peripheral surface of the shaft 31 that opens out of the outer opening portion 31c. The radially inner end of the first groove portion 55 is connected to the outer opening portion 31c. In addition, the radially inner end of the first groove portion 55 may be directly connected to the outer opening portion 31c, or may be indirectly connected to the outer opening portion 31c via a gap.

[0054] like Figure 6As shown, the oil O that flows from the gap portion 37 to the outside of the shaft 31 through the through hole 31a flows into the first groove portion 55. The oil O that flows into the first groove portion 55 flows radially outward along the groove bottom surface 55d described later of the first groove portion 55 by the centrifugal force generated by the rotation of the rotor 30, and blows toward the coil end 42a. As a result, a portion of the oil O that flows into the gap portion 37 is provided to the coil end 42a. Therefore, the coil end 42a can be cooled by the oil O. The oil O provided to the coil end 42a falls to the lower side and accumulates in the lower area of ​​the motor housing 20. The oil O accumulated in the lower area of ​​the motor housing 20 returns to the gear housing 61 through the partition wall opening 22a provided in the partition wall portion 22. Thus, the drive device 100 of this embodiment is provided with the following oil O circulation path: the oil O lifted by the ring gear 63a in the gear housing 61 is provided to the coil end 42a via the gap portion 37 of the shaft 31 and the end plate 50a, and then returns to the gear housing 61 again.

[0055] like Figure 5 As shown, the radially outer end of the first groove portion 55 is located radially outward from the radially inner edge of the wall portion 52. The radially outer end of the first groove portion 55 is located radially inward from the radially outer edge of the wall portion 52. In the present embodiment, the radially outer end of the first groove portion 55 is located at the radial center of the wall portion 52.

[0056] The inner surface of the first groove portion 55 has a groove bottom surface 55d located on the side where the rotor core 32 is located in the axial direction, that is, on the left side (+Y side). The groove bottom surface 55d is a surface facing the right side (-Y side) and extends in the radial direction when viewed in the axial direction. In the present embodiment, the radial inner end of the groove bottom surface 55d is arranged so as to be away from the shaft 31 toward the radial outer side. Therefore, even if the axial position of the end plate 50a relative to the through hole 31a is offset due to dimensional tolerance and assembly tolerance, etc., it is possible to prevent the outer opening 31c of the through hole 31a from being closed by the portion of the end plate 50a provided with the groove bottom surface 55d. As a result, it is possible to prevent the oil O from flowing into the first groove portion 55 through the through hole 31a.

[0057] In the present embodiment, a through portion 51c is provided in the end plate body 51 at the radially inner end portion of the first groove portion 55, which penetrates the portion in the axial direction, so that the radially inner end portion of the groove bottom surface 55d is arranged in a manner radially outwardly away from the shaft 31. The radially inner end portion of the groove bottom surface 55d is arranged to face the outer peripheral surface of the shaft 31 across the interior of the through portion 51c.

[0058] The groove bottom surface 55d has a first surface 55a, a second surface 55b, and a third surface 55c. The second surface 55b, the third surface 55c, and the first surface 55a are arranged so as to be continuously connected in order from the radial inner side toward the radial outer side.

[0059] The first surface 55a is located on the right side (-Y side) as it goes radially outward. That is, the first surface 55a is a surface that is axially away from the rotor core 32 as it goes radially outward. Figure 6 As shown by the middle arrow, the oil O flowing radially outward along the first surface 55a flows in a direction axially away from the rotor core 32. As a result, the oil O sprayed from the first groove portion 55 toward the coil end 42a can be more easily splashed to a position axially away from the rotor core 32. Therefore, it is easy to properly provide the oil O to the portion of the coil end 42a that is relatively far from the rotor core 32 in the axial direction. In addition, the oil O sprayed from the first groove portion 55 toward the coil end 42a is diffused and scattered to a certain extent in the axial direction. Therefore, the oil O is also provided to the portion of the coil end 42a that is relatively close to the rotor core 32 in the axial direction. As described above, according to the present embodiment, the oil O as a refrigerant can be easily provided to the entire coil end 42a via the end plate 50a.

[0060] In addition, for example, if the axial position of the outer opening portion 31c of the through hole 31a is set to a position farther away from the rotor core 32 in the axial direction, the oil O flowing out of the outer opening portion 31c can be easily supplied to the portion of the coil end 42a that is relatively far from the rotor core 32 in the axial direction. However, in this case, the end plate 50a needs to be enlarged in the axial direction. Therefore, there are problems such as the increase in the mass of the rotor 30 and the increase in the size of the rotor 30 in the axial direction. In contrast, according to the present embodiment, the oil O flowing out of the outer opening portion 31c can be easily supplied to the portion of the coil end 42a that is relatively far from the rotor core 32 in the axial direction without setting the axial position of the outer opening portion 31c to a position far away from the rotor core 32. Therefore, it is possible to suppress the increase in the mass of the rotor 30 and the increase in the size of the rotor 30 in the axial direction, and it is possible to easily supply the oil O as a refrigerant to the coil end 42a via the end plate 50a.

[0061] Here, when the coil 42c constituting the coil end 42a is made of a flat wire as in the present embodiment, the axial dimension of the coil end 42a tends to become larger. Therefore, the axial end of the coil end 42a that is away from the rotor core 32 is easily arranged at a position farther from the rotor core 32. Therefore, it is difficult to supply oil O to the portion of the coil end 42a that is relatively far from the rotor core 32 in the axial direction. In contrast, according to the present embodiment, as described above, it is also possible to easily supply oil O to the portion of the coil end 42a that is away from the rotor core 32 in the axial direction. Therefore, even if the coil 42c is made of a flat wire and the axial dimension of the coil end 42a becomes larger, oil O can be appropriately supplied to the coil end 42a.

[0062] In addition, according to the present embodiment, the radially inner end of the first groove portion 55 is located radially inwardly relative to the radially inner edge of the wall portion 52, and the radially outer end of the first groove portion 55 is located radially outwardly relative to the radially inner edge of the wall portion 52. Therefore, the first groove portion 55 can be made longer in the radial direction, and the oil O can be more appropriately guided toward the coil end portion 42a through the first groove portion 55. In addition, the position where the oil O splashes out from the first groove portion 55 can be made closer to the radially outer side, and the position where the oil O splashes out from the first groove portion 55 can be made closer to the coil end portion 42a. Therefore, the oil O can be easily and more appropriately supplied to the coil end portion 42a.

[0063] like Figure 5 and Figure 6 As shown, in the present embodiment, the first surface 55a is a planar inclined surface that is inclined axially relative to the radial direction and extends in a straight line. The inclination angle θa of the first surface 55a relative to the plane perpendicular to the axial direction is, for example, about 5° or more and 30° or less. The radially outer end of the first surface 55a is the radially outer end of the groove bottom surface 55d. The radially outer end of the first surface 55a is connected to the radially outer portion of the inner edge of the groove opening portion 55e. Therefore, it is easy to make the direction of the oil O sprayed from the first groove portion 55 toward the coil end 42a become the direction along the first surface 55a, and it is easy to more appropriately provide the oil O to the portion of the coil end 42a that is relatively far away from the rotor core 32 in the axial direction.

[0064] In the present embodiment, the radially outer end of the first surface 55a is located at the same position as the right end surface of the wall portion 52 in the axial direction, and is connected to the right end surface of the wall portion 52. The radially outer end of the first surface 55a is located at the rightmost side (-Y side) in the slot bottom surface 55d, and is located at a position farthest from the rotor core 32 in the axial direction. The radially outer end of the first surface 55a is located radially outward of the radially inner edge of the wall portion 52. The radially inner end of the first surface 55a is located radially inward of the radially inner edge of the wall portion 52.

[0065] like Figure 6 As shown, in the cross section along the axial direction, the imaginary line IL extending radially outward from the radially outer end of the first surface 55a in the direction along the first surface 55a passes through the coil end 42a. Therefore, the oil O injected radially outward from the first groove portion 55 along the first surface 55a can be more appropriately provided to the coil end 42a.

[0066] The imaginary line IL is a line extending axially obliquely relative to the radial direction, and the imaginary line IL is located on the right side as it moves toward the radial outside. The inclination of the imaginary line IL relative to the radial direction is the same as the inclination of the first surface 55a relative to the radial direction. The position where the imaginary line IL intersects the coil end 42a is a position axially farther from the stator core 41 than the axial center CL1 of the coil end 42a. Therefore, the oil O injected radially outward from the first groove portion 55 along the first surface 55a can be easily provided to the portion of the coil end 42a that is axially farther from the stator core 41 than the axial center CL1. As a result, it is easy to more appropriately provide the oil O to the portion of the coil end 42a that is relatively far from the rotor core 32 in the axial direction.

[0067] In the present embodiment, the "portion of the coil end 42a that is relatively far from the rotor core 32 in the axial direction" includes, for example, a portion of the coil end 42a that is located axially farther from the rotor core 32 than the axial center CL1, that is, a portion of the coil end 42a that is located on the right side (-Y side) of the center CL1. In the present embodiment, the "portion of the coil end 42a that is relatively close to the rotor core 32 in the axial direction" includes, for example, a portion of the coil end 42a that is located axially closer to the rotor core 32 than the axial center CL1, that is, a portion of the coil end 42a that is located on the left side (+Y side) of the center CL1. The axial center CL1 of the coil end 42a may be included in the "portion of the coil end 42a that is relatively far from the rotor core 32 in the axial direction" or in the "portion of the coil end 42a that is relatively close to the rotor core 32 in the axial direction".

[0068] In the present embodiment, the position where the imaginary line IL intersects the coil end 42a is substantially the same as the axial center CL2 of the portion of the coil end 42a that protrudes axially from the stator core 41 more than the insulator 43, that is, the portion of the coil end 42a that is located to the right of the insulator 43. More specifically, the position where the imaginary line IL intersects the coil end 42a is slightly closer to the stator core 41 than the center CL2 in the axial direction. By making the position where the imaginary line IL intersects the coil end 42a be the same as the axial center CL2 of the portion of the coil end 42a that protrudes axially from the stator core 41 more than the insulator 43, or being closer to the stator core 41 than the center CL2 in the axial direction, it is possible to prevent the oil O injected radially outward from the first groove 55 along the first surface 55a from being difficult to be supplied to the portion of the coil end 42a that is relatively close to the rotor core 32 in the axial direction. Therefore, it is possible to easily and more appropriately supply the oil O to the coil end 42a.

[0069] The second surface 55b is located radially inwardly of the first surface 55a. The second surface 55b is located on the right side (-Y side) as it goes radially outwardly. That is, the second surface 55b is a surface that is axially away from the rotor core 32 as it goes radially outwardly. Therefore, the axial position of the radially inner end of the first surface 55a, which is located radially outwardly of the second surface 55b, can be easily arranged at a position axially away from the rotor core 32. Thus, the axial position of the radially inner end of the first surface 55a can be appropriately adjusted, the inclination of the first surface 55a with respect to the radial direction can be appropriately made, and the axial position and radial position of the first surface 55a can be appropriately adjusted.

[0070] In the present embodiment, the radially inner end of the second surface 55b is the radially inner end of the groove bottom surface 55d. Therefore, the radially inner end of the groove bottom surface 55d can be inclined obliquely with respect to the radial direction and arranged at a position close to the rotor core 32 in the axial direction. Thus, the oil O flowing out from the outer opening 31c of the through hole 31a can be easily guided into the first groove portion 55 through the radially inner end of the groove bottom surface 55d, that is, the radially inner end of the second surface 55b. Therefore, the oil O flowing out from the outer opening 31c can be easily flowed into the first groove portion 55.

[0071] In this embodiment, the second surface 55b and the outer opening portion 31c are radially opposed. Figure 6As shown by the arrow in the middle, the oil O flowing out from the outer opening 31c to the radial outside can be brought into contact with the second surface 55b. Thus, the flow of the oil O flowing out from the outer opening 31c to the radial outside can be adjusted by the second surface 55b and then flow to the first surface 55a. Therefore, it is easy to stabilize the flow of the oil O ejected toward the coil end 42a along the first surface 55a. Therefore, the oil O can be stably and appropriately supplied to the coil end 42a.

[0072] In addition, in this specification, regarding "a certain object is opposite to each other in a certain direction", it is sufficient that the certain objects overlap each other at least in part when viewed in a certain direction, and the shape and direction of the part of the certain object that is opposite to another object can be oriented in any direction. For example, regarding "the second surface 55b and the outer opening portion 31c are opposite in the radial direction", it is sufficient that the second surface 55b and the outer opening portion 31c overlap at least in part when viewed in at least one radial direction passing through the outer opening portion 31c in the radial direction, and it is not necessary for the second surface 55b to be opposite to the outer opening portion 31c in parallel. In this embodiment, the direction perpendicular to the second surface 55b is a direction that intersects the direction in which the outer opening portion 31c opens.

[0073] The second surface 55b is arranged with a gap in the radial outside of the outer opening portion 31c. In the present embodiment, the second surface 55b is a planar inclined surface that is inclined axially relative to the radial direction and extends linearly. The inclination angle θb of the second surface 55b relative to the plane perpendicular to the axial direction is larger than the inclination angle θa of the first surface 55a relative to the plane perpendicular to the axial direction. Therefore, the radial dimension of the second surface 55b can be made relatively small, and the radial outer end of the second surface 55b can be located at a position away from the rotor core 32 in the axial direction. Thus, the axial position of the first surface 55a can be appropriately adjusted by the second surface 55b, and the second surface 55b can be prevented from becoming too large in the radial direction. Therefore, it is easy to make the inclination angle θa of the first surface 55a an appropriate angle, and it is easy to adjust the axial position and radial position of the first surface 55a by the second surface 55b. In addition, the oil O flowing out of the outer opening 31c can be easily brought into contact with the second surface 55b appropriately, and the flow of the oil O can be more appropriately adjusted by the second surface 55b. The inclination angle θb of the second surface 55b relative to the plane perpendicular to the axial direction is, for example, about 5° to 30°.

[0074] The dimension of the second surface 55b in the direction in which the second surface 55b extends is smaller than the dimension of the first surface 55a in the direction in which the first surface 55a extends. The radial dimension of the second surface 55b is smaller than the radial dimension of the first surface 55a. The axial dimension of the second surface 55b is smaller than the axial dimension of the first surface 55a. The radially outer end of the second surface 55b is axially arranged at the same position as the radially inner end of the first surface 55a.

[0075] The third surface 55c is a surface connecting the first surface 55a and the second surface 55b. The third surface 55c is a flat surface along a plane perpendicular to the axial direction. Therefore, the oil O adjusted by contacting the second surface 55b can be appropriately flowed radially outward along the third surface 55c. Thus, the flow velocity of the oil O after contacting the second surface 55b can be easily increased, and the oil O can be flowed along the first surface 55a in a state where the flow velocity of the oil O is relatively large. Therefore, it is easy to appropriately increase the momentum of the oil O ejected from the first surface 55a to the coil end 42a, and the oil O can be more appropriately provided to the coil end 42a. In addition, the oil O can be guided radially outward along the third surface 55c while keeping the axial position of the radially inner end of the first surface 55a the same as the axial position of the radially outer end of the second surface 55b. Therefore, the oil O can be guided to the first surface 55 a without changing the axial position and radial position of the first surface 55 a adjusted by the second surface 55 b .

[0076] The third surface 55c extends in the radial direction. The radial inner end of the third surface 55c is connected to the radial outer end of the second surface 55b. The radial outer end of the third surface 55c is connected to the radial inner end of the first surface 55a. The dimension of the third surface 55c in the direction in which the third surface 55c extends is larger than the dimension of the second surface 55b in the direction in which the second surface 55b extends, and is smaller than the dimension of the first surface 55a in the direction in which the first surface 55a extends. The radial dimension of the third surface 55c is larger than the radial dimension of the second surface 55b, and is smaller than the radial dimension of the first surface 55a.

[0077] A portion of the first groove portion 55 is covered from the right side by the nut 36. The nut 36 as a protruding portion closes a portion of the groove opening portion 55e. Thus, the first groove portion 55 and the nut 36 can constitute a flow path for conveying the oil O to the radially outer side, and the oil O can flow more appropriately in the first groove portion 55. In the present embodiment, the nut 36 as a protruding portion closes the portion of the groove opening portion 55e that overlaps with the second surface 55b and the third surface 55c when viewed in the axial direction. Therefore, a flow path for the oil O to flow between the second surface 55b and the third surface 55c and the nut 36 in the axial direction can be made, and the oil O can be appropriately guided to the first surface 55a. In addition, the oil O flowing along the second surface 55b can be suppressed from scattering in the axial direction from the radially outer end of the second surface 55b by the nut 36. Therefore, the oil O flowing along the second surface 55b can be appropriately flowed to the radially outer side along the third surface 55c, and the oil O can be sprayed from the first surface 55a to the coil end 42a.

[0078] In the present embodiment, the radially outer end of the nut 36 is located at substantially the same radial position as the radially outer end of the third surface 55c. The left end of the nut 36 is disposed on the radially inner side of the first surface 55a in a manner opposed to each other with a gap therebetween. The left end of the nut 36 is located to the left of the right end of the wall portion 52.

[0079] like Figure 3 and Figure 4 As shown, the end plate 50a has a plurality of first grooves 55. The plurality of first grooves 55 are arranged at equal intervals in the circumferential direction. Therefore, the oil O sprayed radially outward from the plurality of first grooves 55 can be provided to the coil end 42a in a balanced manner in the circumferential direction. Thus, the coil end 42a can be properly cooled over the entire circumference. In the present embodiment, four first grooves 55 are provided. The four first grooves 55 are arranged at 90° intervals in the circumferential direction. The outer openings 31c of the four through holes 31a are respectively connected to the radially inner ends of the four first grooves 55.

[0080] like Figure 7 As shown, the end plate 50a has a fourth surface 51a for the nut 36 as a protrusion to contact. Figure 4 As shown, the fourth surface 51a is an arc-shaped surface extending in the circumferential direction. A plurality of fourth surfaces 51a are provided at intervals in the circumferential direction. In the present embodiment, four fourth surfaces 51a are provided. The four fourth surfaces 51a are respectively produced by dividing the radial inner portion of the right side surface of the end plate main body 51 into four parts in the circumferential direction by the four first grooves 55. Each fourth surface 51a is a surface along a plane perpendicular to the axial direction.

[0081] like Figure 7 As shown, the left side surface of the nut 36 contacts the fourth surface 51a. The radially outer end of the fourth surface 51a is located slightly radially outward than the radially outer end of the nut 36. The radially inner end of the fourth surface 51a is the radially inner end of the right side surface of the end plate main body 51. The fourth surface 51a is provided with a second groove 53a that opens on the right side. Therefore, the end plate 50a can be made lighter. Figure 4 As shown in the figure, the second groove portion 53a is in the shape of an arc extending in the circumferential direction. One second groove portion 53a is provided for each fourth surface 51a. That is, four second groove portions 53a are provided at intervals in the circumferential direction. Each second groove portion 53a is located between the first groove portions 55 adjacent to each other in the circumferential direction. Both circumferential ends of the second groove portion 53a are closed and are arranged to be away from the first groove portion 55 in the circumferential direction.

[0082] like Figure 4 and Figure 7As shown in FIG. 1 , the axial opening of the second groove portion 53a is closed by the nut 36 as a protruding portion. Therefore, the oil O is suppressed from flowing into the second groove portion 53a. Thus, the second groove portion 53a is provided to reduce the weight of the end plate 50a, and the oil O flowing in the first groove portion 55 can be suppressed from leaking into the second groove portion 53a. Therefore, the amount of oil O flowing in the first groove portion 55 can be suppressed from decreasing, and the amount of oil O supplied from the first groove portion 55 to the coil end portion 42a can be suppressed from decreasing.

[0083] like Figure 3 As shown, the end plate 50a has a fifth surface 51g protruding from the radially outer edge of the fourth surface 51a in a direction close to the rotor core 32 in the axial direction, that is, to the left (+Y direction). The fifth surface 51g is an arc-shaped surface extending in the circumferential direction toward the radially outer side. A plurality of fifth surfaces 51g are provided at intervals in the circumferential direction. In the present embodiment, four fifth surfaces 51g are provided. The four fifth surfaces 51g protrude to the left (+Y side) from the radially outer edges of the four fourth surfaces 51a.

[0084] like Figure 3 As shown, the end plate 50a has a third groove portion 53b opened on the right side. Therefore, the end plate 50a can be further lightened. The third groove portion 53b is provided in a portion located between the wall portion 52 and the fourth surface 51a in the radial direction in the right side surface of the end plate main body 51. The third groove portion 53b is in the shape of a circular arc extending in the circumferential direction. Four third groove portions 53b are provided at intervals in the circumferential direction. Each third groove portion 53b is located between the first groove portions 55 adjacent to each other in the circumferential direction. Both circumferential ends of the third groove portion 53b are closed and arranged to be away from the first groove portion 55 in the circumferential direction. Each third groove portion 53b is located at a position radially outward of each second groove portion 53a. Each third groove portion 53b is separately arranged radially outward of each second groove portion 53a. The radial width of the third groove portion 53b is larger than the radial width of the second groove portion 53a.

[0085] The radially outer surface of the inner surface of each third groove portion 53b is formed by the radially inner surface of the wall portion 52. Therefore, the third groove portion 53b can be provided at a position adjacent to the radially inner side of the wall portion 52. As a result, the radial width of the third groove portion 53b can be easily increased, and the weight of the end plate 50a can be more appropriately reduced.

[0086] The radially inner surface of each third groove portion 53b is formed by each fifth surface 51g. Therefore, the third groove portion 53b can be provided at a position radially outward from the fourth surface 51a and adjacent to the fourth surface 51a. As a result, it is easy to make the radial width of the third groove portion 53b more appropriately larger, and the end plate 50a can be more appropriately lightweight. In addition, the third groove portion 53b can be provided at a position radially outward from the fourth surface 51a, so that the fourth surface 51a can be appropriately contacted with the nut 36, and the end plate 50a can be appropriately fixed to the rotor core 32 by the nut 36, and the end plate 50a can be lightweight.

[0087] like Figure 3 and Figure 4 As shown, the end plate 50a has a pair of side wall portions 56a and 56b respectively arranged on both sides of the first groove portion 55 in the circumferential direction. The pair of side wall portions 56a and 56b are walls that separate the interior of each third groove portion 53b located on both sides of the first groove portion 55 in the circumferential direction from the interior of the first groove portion 55 in the circumferential direction. The pair of side wall portions 56a and 56b protrude to the right side (-Y side) from the circumferential end of the third groove portion 53b. The radially outer ends of the pair of side wall portions 56a and 56b are connected to the wall portion 52. Therefore, the oil O in the first groove portion 55 can be appropriately guided to the radially outer end of the first groove portion 55 provided on the wall portion 52 by the pair of side wall portions 56a and 56b. In addition, it is possible to suppress the oil O flowing in the first groove portion 55 from leaking to the third groove portions 53b located on both sides of the first groove portion 55 in the circumferential direction.

[0088] The radially inner ends of the pair of side wall portions 56a, 56b are located radially outward of the fourth surface 51a. The right ends of the pair of side wall portions 56a, 56b are arranged at the same position as the right end of the wall portion 52 in the axial direction. A pair of side wall portions 56a, 56b is provided for each first groove portion 55. That is, four pairs of the pair of side wall portions 56a, 56b are provided at intervals in the circumferential direction.

[0089] like Figure 6 As shown in FIG. 1 , the end plate 50a has a recessed portion 51d recessed to the right from the surface of the end plate main body 51 that contacts the rotor core 32, that is, the left surface of the end plate main body 51. Therefore, the end plate 50a can be further reduced in weight. The recessed portion 51d is annular centered on the central axis J. The recessed portion 51d has a first recessed portion 51e and a second recessed portion 51f.

[0090] The first recess 51e is provided in a portion of the end plate main body 51 that is located radially inward of the radially outer edge of the wall portion 52. The radially inner edge of the first recess 51e is located radially inward of the radially outer end of the third surface 55c, and is located radially outward of the radially inner end of the third surface 55c. The radially outer end of the first recess 51e is provided in a portion of the end plate main body 51 that overlaps with the radially inner portion of the wall portion 52 when viewed in the axial direction.

[0091] The second recess 51f is connected to the radially outer side of the first recess 51e. The second recess 51f is provided in a portion of the end plate main body 51 that overlaps with the wall portion 52 when viewed in the axial direction. The axial dimension of the second recess 51f is larger than the axial dimension of the first recess 51e. In this way, by providing the second recess 51f having a larger axial depth in the portion of the end plate 50a whose axial dimension is increased due to the wall portion 52, the strength of the end plate 50a can be ensured, and the end plate 50a can be further reduced in weight. The radially outer edge of the second recess 51f is located radially inward of the radially outer edge of the wall portion 52.

[0092] like Figure 3 and Figure 4 As shown, the end plate 50a has a protrusion 54 protruding radially inward from the inner edge of the end plate body 51. Figure 5 As shown, the protrusion 54 is engaged with the groove 31d extending in the axial direction and provided on the outer peripheral surface of the shaft 31. Therefore, the relative movement of the end plate 50a in the circumferential direction with respect to the shaft 31 is suppressed. As a result, the end plate 50a can be positioned with high precision in the circumferential direction with respect to the shaft 31. Therefore, the circumferential position of the outer opening portion 31c of the through hole 31a can be appropriately aligned with the circumferential position of the first groove portion 55. Therefore, the oil O flowing out from the outer opening portion 31c can be appropriately flowed into the first groove portion 55.

[0093] like Figure 3 and Figure 4 As shown, in the present embodiment, a pair of protrusions 54 are provided across the central axis J in the radial direction. Although not shown in the figure, a pair of grooves 31d provided on the shaft 31 are also provided across the central axis J. The pair of protrusions 54 are respectively engaged with the pair of grooves 31d. In addition, a recess may be provided on the inner edge of the end plate body 51 instead of providing the protrusions 54, and a protrusion engaged with the recess may be provided on the outer peripheral surface of the shaft 31 instead of providing the grooves 31d.

[0094] like Figure 2As shown, the end plate 50b has the first groove portion 57 similarly to the end plate 50a. The first groove portion 57 is the same as the first groove portion 55 except that it is symmetrically arranged in the axial direction. A portion of the groove opening portion 57e of the first groove portion 57 is closed by the flange portion 31e as a protrusion provided on the shaft 31. The flange portion 31e closes the radial inner end of the groove opening portion 57e from the left side. The radial outer end of the flange portion 31e is located radially inward of the third surface 57c of the first groove portion 57. The radial outer end of the flange portion 31e is located radially inward of the radial outer end of the second surface 57b of the first groove portion 57, and is located radially outward of the radial inner end of the second surface 57b of the first groove portion 57.

[0095] like Figure 1 As shown, in the present embodiment, a refrigerant flow path 90 for circulating oil O as a refrigerant is provided in the drive device 100. The refrigerant flow path 90 is provided in a manner spanning the inside of the motor housing 20 and the inside of the gear housing 61. The refrigerant flow path 90 is a path for the oil O stored in the gear housing 61 to be supplied to the rotary electric machine 10 and returned to the gear housing 61 again. The pump 71, the cooler 72, and the refrigerant supply unit 94 are provided in the refrigerant flow path 90. The refrigerant flow path 90 includes a first flow path portion 91, a second flow path portion 92, a third flow path portion 93, and a refrigerant supply unit 94.

[0096] The first flow path 91, the second flow path 92, and the third flow path 93 are provided, for example, on the wall of the gear housing 61. The first flow path 91 connects the portion of the gear housing 61 in which the oil O is stored to the pump 71. The second flow path 92 connects the pump 71 to the cooler 72. The third flow path 93 connects the cooler 72 to the inside of the refrigerant supply unit 94. In the present embodiment, the third flow path 93 is connected to the left end of the refrigerant supply unit 94.

[0097] The refrigerant supply portion 94 is disposed inside the motor housing 20. In the present embodiment, the refrigerant supply portion 94 is in the shape of a tube extending in the axial direction. In other words, in the present embodiment, the refrigerant supply portion 94 is a tube extending in the axial direction. Both axial ends of the refrigerant supply portion 94 are supported by the motor housing 20. The left end of the refrigerant supply portion 94 is supported by, for example, the partition wall portion 22. The right end of the refrigerant supply portion 94 is supported by, for example, the cover portion 23. The refrigerant supply portion 94 is located radially outside the stator 40. In the present embodiment, the refrigerant supply portion 94 is located on the upper side of the stator 40.

[0098] The refrigerant supply portion 94 has a supply port 94a for supplying oil O as a refrigerant to the stator 40. In the present embodiment, the supply port 94a is an injection port for injecting a portion of the oil O flowing into the refrigerant supply portion 94 to the outside of the refrigerant supply portion 94. A plurality of supply ports 94a are provided. A plurality of supply ports 94a are provided at intervals in the axial direction. The axial positions of the plurality of supply ports 94a are included in the axial position of the stator core 41. The plurality of supply ports 94a are located to the left of the coil end portion 42a and to the right of the coil end portion 42b.

[0099] The plurality of supply ports 94a are open toward the stator core 41. Therefore, the oil O ejected from the plurality of supply ports 94a is supplied to the stator core 41. Thus, the stator core 41 can be cooled by the oil O. Here, the oil O supplied to the stator core 41 easily reaches the portion of each coil end 42a, 42b relatively close to the stator core 41 in the axial direction along the surface of the stator core 41. Therefore, the portion of the coil end 42a, 42b relatively close to the stator core 41 in the axial direction can be easily cooled by the oil O supplied from the supply port 94a to the stator 40. Therefore, even if the position where the imaginary line IL intersects the coil end 42a is a position relatively far from the stator core 41 in the axial direction, and the oil O is easily ejected from the first grooves 55, 57 to the position of each coil end 42a, 42b relatively far from the stator core 41 in the axial direction, it is possible to suppress the portion of the coil end 42a, 42b relatively close to the stator core 41 in the axial direction from being difficult to be cooled. Therefore, the oil O as the refrigerant can be easily and appropriately supplied to the entire coil end portions 42a, 42b.

[0100] In the present embodiment, the refrigerant supply unit 94 does not have a supply port that opens toward the coil ends 42a, 42b and a supply port that directly supplies the oil O to the coil ends 42a, 42b. Thus, the amount of oil O supplied from the refrigerant supply unit 94 to the stator core 41 can be appropriately increased. In the present embodiment, the oil O can be appropriately supplied to the coil ends 42a, 42b from the gap 37 of the shaft 31 via the end plates 50a, 50b, so even if the oil O is not supplied from the refrigerant supply unit 94 to the coil ends 42a, 42b, it is possible to suppress the insufficient cooling of the coil ends 42a, 42b. In addition, the refrigerant supply unit 94 does not have a supply port that actively supplies the oil O to the coil ends 42a, 42b, but as described above, a portion of the oil O supplied from the refrigerant supply unit 94 to the stator core 41 may flow to the coil ends 42a, 42b.

[0101] When the pump 71 is driven, the oil O stored in the gear housing 61 is sucked up through the first flow path portion 91, and flows into the cooler 72 through the second flow path portion 92. The oil O that has flowed into the cooler 72 is cooled in the cooler 72, and then flows into the inside of the refrigerant supply portion 94 through the third flow path portion 93. The oil O that has flowed into the refrigerant supply portion 94 is ejected from the supply port 94a and supplied to the stator 40.

[0102] The oil O supplied from the supply port 94a to the stator 40 removes heat from the stator 40. The oil O after cooling the stator 40 falls downward and accumulates in the lower region of the motor housing 20. The oil O accumulated in the lower region of the motor housing 20 returns to the gear housing 61 through the partition wall opening 22a provided in the partition wall portion 22.

[0103] As described above, in this embodiment, the rotating motor 10 can be cooled by two paths: a path in which the oil O flows into the gap portion 37 of the shaft 31 through the reservoir 65 after being lifted by the ring gear 63a, and a path in which the oil O is provided from the first groove portions 55, 57 to the coil ends 42a, 42b and a path in which the oil O is provided to the stator 40 through the refrigerant flow path 90.

[0104] <Second embodiment>

[0105] In the following description, the same structures as those in the above-mentioned embodiment are sometimes omitted by appropriately marking the same reference numerals. Figure 8 As shown, in the end plate 250a of the rotor 230 of the present embodiment, the radially outer end of the first groove portion 255 is located radially outward from the radially inner edge of the wall portion 52. Therefore, even if a part of the wall portion 52 needs to be removed by cutting for circumferential balance adjustment of the rotor 230, a part of the first groove portion 255 will not be removed. Thus, even if the circumferential balance adjustment of the rotor 230 is performed, the amount of oil O supplied from the first groove portion 255 to the coil end portion 42a and the direction of the oil O ejected from the first groove portion 255 can be suppressed from changing. The other structures of the first groove portion 255 are the same as those of the first groove portion 55 of the first embodiment.

[0106] The end plate 250a has a connecting wall portion 258 protruding from the end plate main body portion 251 in a direction away from the rotor core 32 in the axial direction. The connecting wall portion 258 is in the shape of an arc extending in the circumferential direction. The connecting wall portion 258 protrudes to the right side (-Y side) from the radially inner edge of the third groove portion 53b. A plurality of connecting wall portions 258 are arranged at intervals in the circumferential direction. For example, four connecting wall portions 258 are provided. Each connecting wall portion 258 is located between the side wall portion 56a of a pair of side wall portions 56a, 56b and the side wall portion 56b of the other pair of side wall portions 56a, 56b, and the other pair of side wall portions 56a, 56b are adjacent to the pair of side wall portions 56a, 56b in the circumferential direction. Each connecting wall portion 258 connects the side wall portion 56a of a pair of side wall portions 56a, 56b to the side wall portion 56b of the other pair of side wall portions 56a, 56b.

[0107] Unlike the first embodiment, the second groove portion 53a is not provided on each fourth surface 251a of the present embodiment. A sixth surface 251b is provided on the radially outer side of each fourth surface 251a, and the sixth surface 251b is located at a position axially farther from the rotor core 32 than the fourth surface 251a. The sixth surface 251b is located at a position to the right (-Y side) than the fourth surface 251a. The sixth surface 251b is in the shape of an arc extending in the circumferential direction. The sixth surface 251b is provided between the fourth surface 251a and the connecting wall portion 258 in the radial direction. The other structures of the end plate 250a are the same as the other structures of the end plate 50a of the first embodiment.

[0108] The present invention is not limited to the above-mentioned embodiments, and other structures and other methods can also be adopted within the scope of the technical idea of ​​the present invention. The first surface of the slot bottom surface of the first slot portion can be any surface as long as it is a surface that moves axially away from the rotor core as it moves radially outward. The first surface can also be a curved surface. In addition, the first surface can also be set at any position in the slot bottom surface. The inclination angle of the first surface relative to the plane perpendicular to the axial direction is not particularly limited. In the cross section along the axial direction, the imaginary line extending radially outward from the radially outer end of the first surface in the direction along the first surface can also pass through any part of the coil end.

[0109] The second surface of the groove bottom surface of the first groove portion can be any surface as long as it is located radially inward than the first surface and is axially away from the rotor core as it moves radially outward. The second surface can also be a curved surface. The second surface may not be radially opposite to the first opening portion of the through hole provided on the shaft. The inclination angle of the second surface relative to the plane perpendicular to the axial direction may be the same as the inclination angle of the first surface relative to the plane perpendicular to the axial direction, or it may be smaller than the inclination angle of the first surface relative to the plane perpendicular to the axial direction. The inclination angle of the second surface relative to the plane perpendicular to the axial direction may also be determined according to the axial size of the coil end. The second surface may also be omitted.

[0110] The groove bottom surface of the first groove portion may not have a third surface connecting the first surface and the second surface. In this case, the first surface and the second surface may be directly connected. The radial inner end of the groove bottom surface of the first groove portion may also be in contact with the outer peripheral surface of the shaft. The number of the first groove portions is not particularly limited as long as it is one or more.

[0111] The protrusion protruding radially outward from the outer peripheral surface of the shaft may be part of the same single component as the shaft, or may be separate from the shaft. The shape of the protrusion is not particularly limited. In the case where the protrusion is separate from the shaft, the protrusion may be a component other than a nut such as a washer. The end plate may not be provided with a wall protruding in a direction away from the rotor core in the axial direction.

[0112] The rotary electric machine to which the present invention is applied is not limited to a motor, but may also be a generator. The purpose of the rotary electric machine is not particularly limited. For example, the rotary electric machine may be mounted on a vehicle for purposes other than rotating an axle, or may be mounted on equipment other than a vehicle. The posture when the rotary electric machine is used is not particularly limited. The central axis of the rotary electric machine may also extend in the vertical direction. The supply of the refrigerant to the gap portion of the shaft in the rotary electric machine may be performed in any manner. The shaft may have any structure as long as it has a gap portion. The refrigerant may also be a substance other than oil.

[0113] In addition, the present technology can adopt the following structures.

[0114] (1) A rotor capable of rotating about a central axis, wherein the rotor comprises: a shaft extending in an axial direction; a rotor core fixed to the shaft; and an end plate arranged in an axial direction with the rotor core, the shaft comprising: a gap portion provided inside the shaft; and a through hole connected to the gap portion, the through hole having a first opening portion opening on an outer peripheral surface of the shaft, the end plate having a first groove portion extending in a radial direction, the first groove portion having a second opening portion opening on an axial side opposite to a side where the rotor core is located, a radially inner end portion of the first groove portion being connected to the first opening portion, an inner surface of the first groove portion having a groove bottom surface located in an axial direction on a side where the rotor core is located, the groove bottom surface having a first surface which is axially away from the rotor core as it moves radially outward.

[0115] (2) The rotor according to (1), wherein the radially outer end of the first surface is the radially outer end of the groove bottom surface and is continuous with a radially outer portion of the inner edge of the second opening.

[0116] (3) A rotor according to (1) or (2), wherein the slot bottom surface has a second surface located radially inward of the first surface, and the second surface is a surface that is axially away from the rotor core as it moves radially outward.

[0117] (4) The rotor according to (3), wherein the second surface and the first opening are opposed to each other in the radial direction.

[0118] (5) The rotor according to (3) or (4), wherein an inclination angle of the second surface relative to a plane perpendicular to the axial direction is larger than an inclination angle of the first surface relative to the plane perpendicular to the axial direction.

[0119] (6) The rotor according to any one of (3) to (5), wherein the slot bottom surface has a third surface connecting the first surface and the second surface, and the third surface is a flat surface along a plane perpendicular to the axial direction.

[0120] (7) A rotor according to (6), wherein the rotor has a protrusion protruding radially outward from the outer peripheral surface of the shaft, the end plate is clamped between the protrusion and the axial direction of the rotor core, and the protrusion closes the portion of the second opening that overlaps with the second surface and the third surface when viewed in the axial direction.

[0121] (8) A rotor according to any one of (1) to (5), wherein the rotor has a protrusion protruding radially outward from the outer peripheral surface of the shaft, the end plate is sandwiched between the protrusion and the rotor core in the axial direction, and the protrusion closes a portion of the second opening.

[0122] (9) The rotor according to (7) or (8), wherein the end plate has a fourth surface with which the protrusion contacts, a second groove is provided on the fourth surface, and an axial opening of the second groove is closed by the protrusion.

[0123] (10) A rotor according to (9), wherein the end plate comprises: a wall portion protruding in a direction away from the rotor core in the axial direction; and a third groove portion located radially outwardly of the second groove portion and extending circumferentially, wherein the wall portion extends circumferentially, and a radially outer surface of an inner surface of the third groove portion is formed by a radially inner surface of the wall portion.

[0124] (11) A rotor according to (10), wherein the end plate has a fifth surface protruding from the radially outer edge of the fourth surface in an axial direction close to the rotor core, and the radially inner surface of the inner surface of the third groove portion is composed of the fifth surface.

[0125] (12) A rotor according to any one of (1) to (9), wherein the end plate has a wall portion protruding in the direction away from the rotor core in the axial direction, the wall portion extends circumferentially, the radially inner end of the first groove portion is located radially inward of the radially inner edge of the wall portion, and the radially outer end of the first groove portion is located radially outward of the radially inner edge of the wall portion.

[0126] (13) The rotor according to (12), wherein the end plate has a pair of side wall portions respectively arranged on both sides of the first groove portion in the circumferential direction, and radially outer ends of the pair of side wall portions are connected to the wall portion.

[0127] (14) The rotor according to any one of (1) to (13), wherein the radially inner end of the groove bottom surface is arranged to be separated from the shaft toward the radially outer side.

[0128] (15) The rotor according to any one of (1) to (14), wherein the end plate has a plurality of the first groove portions, and the plurality of the first groove portions are arranged at equal intervals in the circumferential direction.

[0129] (16) A rotating electric machine comprising: a rotor as described in any one of (1) to (15); and a stator located radially outside the rotor, the stator comprising: a stator core; and a coil end portion which protrudes axially beyond the stator core, wherein, in a cross section along the axial direction, an imaginary line extending radially outward from the radially outer end portion of the first surface in a direction along the first surface passes through the coil end portion.

[0130] (17) The rotating electrical machine according to (16), wherein the position where the imaginary line intersects the coil end is a position axially farther from the stator core than the axial center of the coil end.

[0131] The configurations described above in this specification can be appropriately combined within a range that does not contradict each other.

[0132] Description of symbols

[0133] 10: rotating electrical machine; 30, 230: rotor; 31: shaft; 31a: through hole; 31c: outer opening (first opening); 31e: flange (protrusion); 32: rotor core; 36: nut (protrusion); 37: gap; 40: stator; 41: stator core; 42a, 42b: coil end; 42c: coil; 50, 50a, 50b, 250a: end plate; 51a, 25 1a: 4th surface; 51g: 5th surface; 52: wall portion; 53a: 2nd groove portion; 53b: 3rd groove portion; 55, 57, 255: 1st groove portion; 55a: 1st surface; 55b, 57b: 2nd surface; 55c, 57c: 3rd surface; 55d: groove bottom surface; 55e: groove opening portion (2nd opening portion); 56a, 56b: side wall portion; IL: imaginary line; J: center axis; θa, θb: inclination angles.

Claims

1. A rotor capable of rotating about a central axis, wherein: The rotor has: a shaft extending in an axial direction; a rotor core fixed to the shaft; and an end plate, which is arranged axially with the rotor core, The shaft has: a gap portion disposed inside the shaft; and a through hole connected to the gap portion, The through hole has a first opening portion opened on the outer peripheral surface of the shaft, The end plate has a first groove portion extending in the radial direction. The first groove portion has a second opening portion that opens on the side opposite to the side where the rotor core is located in the axial direction. The radial inner end of the first groove portion is connected to the first opening portion, The inner surface of the first groove portion has a groove bottom surface located on the side where the rotor core is located in the axial direction. The slot bottom surface has a first surface that becomes axially distant from the rotor core as it goes radially outward.

2. The rotor according to claim 1, wherein: The radially outer end of the first surface is the radially outer end of the groove bottom surface, and is connected to a radially outer portion of the inner edge of the second opening.

3. The rotor according to claim 1, wherein: The groove bottom surface has a second surface located radially inward of the first surface. The second surface is a surface that becomes more and more distant from the rotor core in the axial direction as it goes radially outward.

4. The rotor according to claim 3, wherein: The second surface faces the first opening in the radial direction.

5. The rotor according to claim 3, wherein: An inclination angle of the second surface with respect to a plane perpendicular to the axial direction is larger than an inclination angle of the first surface with respect to the plane perpendicular to the axial direction.

6. The rotor according to claim 3, wherein: The groove bottom surface has a third surface connecting the first surface and the second surface, The third surface is a flat surface along a plane perpendicular to the axial direction.

7. The rotor according to claim 6, wherein: The rotor has a protrusion that protrudes radially outward from the outer peripheral surface of the shaft. The end plate is sandwiched between the protruding portion and the rotor core in the axial direction, and the protruding portion closes a portion of the second opening that overlaps with the second surface and the third surface when viewed in the axial direction.

8. The rotor according to claim 1, wherein: The rotor has a protrusion that protrudes radially outward from the outer peripheral surface of the shaft. The end plate is sandwiched between the protruding portion and the rotor core in the axial direction, and the protruding portion closes a portion of the second opening.

9. The rotor according to claim 7, wherein: The end plate has a fourth surface for the protrusion to contact, A second groove is provided on the fourth surface, The axial opening of the second groove is closed by the protrusion.

10. The rotor according to claim 9, wherein: The end plate has: a wall portion protruding in a direction away from the rotor core in the axial direction; and a third groove portion, which is located radially outward of the second groove portion and extends in the circumferential direction, The wall portion extends in the circumferential direction, A radially outer surface of the inner surface of the third groove portion is constituted by a radially inner surface of the wall portion.

11. The rotor according to claim 10, wherein: The end plate has a fifth surface protruding from a radially outer edge of the fourth surface in an axial direction toward the rotor core. A surface located on the radial inner side of the inner surface of the third groove portion is constituted by the fifth surface.

12. The rotor according to claim 1, wherein: The end plate has a wall portion protruding in a direction away from the rotor core in the axial direction. The wall portion extends in the circumferential direction, The radially inner end of the first groove portion is located radially inward of the radially inner edge of the wall portion. The radially outer end portion of the first groove portion is located radially outward of the radially inner edge portion of the wall portion.

13. The rotor according to claim 12, wherein: The end plate has a pair of side wall portions respectively arranged on both sides of the first groove portion in the circumferential direction. The radially outer ends of the pair of side wall portions are connected to the wall portion.

14. The rotor according to claim 1, wherein: The radially inner end of the groove bottom surface is arranged so as to be separated from the shaft toward the radially outer side.

15. The rotor according to claim 1, wherein: The end plate has a plurality of the first grooves. The plurality of first grooves are arranged at equal intervals in the circumferential direction.

16. A rotating electrical machine, comprising: A rotor as claimed in any one of claims 1 to 15; and a stator, which is located radially outside the rotor, The stator has: stator core; and The coil end portion protrudes axially from the stator core. In a cross section along the axial direction, an imaginary line extending radially outward from a radially outer end of the first surface in a direction along the first surface passes through the coil end.

17. The rotating electrical machine according to claim 16, wherein: The position where the imaginary line intersects the coil end is a position farther from the stator core in the axial direction than the axial center of the coil end.

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