JP2019187063A - Rotary electric machine - Google Patents

Abstract

To provide a rotating electrical machine that can sufficiently cool coil ends at both axial direction ends of a rotor and a stator core and that can be easily processed when providing a refrigerant flow path.SOLUTION: A rotating electrical machine 1 includes a first flow path 31 provided in a shaft 11, second and third flow paths 32, 33 formed in a rotor core 12, a fourth flow path 34 formed in the rotor core 12, a fifth flow path 35 formed in a first end plate 13, connecting the first flow path 31 and the second flow path 32, and that is connected to the first flow path 31 and the third flow path 33, and an U-turn channel 37 formed on the second end plate 14 and connecting the third channel 33 and the fourth channel 34. The first end plate 13 is formed with a first discharge port 36 for discharging refrigerant that is passed through the fourth flow path 34 to the outside of the rotor 10, and the second end plate 14 is formed with a second discharge port 38 for discharging the refrigerant that is passed through the second flow path 32 to the outside of the rotor 10.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a rotating electrical machine.

  2. Description of the Related Art Conventionally, there is known a motor cooling structure in which a refrigerant flow path extending in the axial direction of a motor is provided in each of a shaft and a rotor core. Patent Document 1 discloses a cooling of a motor in which a passage connecting a shaft and a coolant flow path of a rotor core is connected to one end plate provided on both axial end surfaces of a rotor core, and a coolant discharge port is formed on the other end plate. A structure is disclosed.

  In this motor cooling structure, the refrigerant flows from one end surface in the axial direction of the shaft, and after the refrigerant is supplied to the refrigerant flow path of the rotor core through the connecting passage formed in one end plate, the other end plate is The refrigerant is discharged from the discharge port. The discharged refrigerant sprays on the coil end in the stator surrounding the rotor.

  Patent Document 2 discloses a diameter in which a refrigerant flow path extending in the axial direction inside the shaft and a refrigerant flow path spirally provided on the outer peripheral surface of the shaft are provided in the central portion in the axial direction of the shaft. A cooling structure for a motor connected by a directional flow path is disclosed. Both ends of the spiral refrigerant flow path provided on the outer peripheral surface of the shaft are connected to discharge ports provided in end plates on both ends of the rotor core.

  In this motor cooling structure, the refrigerant flowed in the axially extending refrigerant flow path in the shaft passes through the flow path extending in the radial direction from the axial central portion of the shaft, and the spiral provided on the outer peripheral surface of the shaft. Is supplied to the refrigerant flow path. The refrigerant supplied to the refrigerant flow path on the outer peripheral surface of the shaft flows in two directions toward both ends, and is discharged from a discharge port provided in the end plate when reaching the end.

JP 2010-220340 A JP 2009-81953 A

  In the motor cooling structure, it is required to cool a magnet in the rotor and a coil in the stator that are particularly likely to be heated to a high temperature among the rotor and the stator constituting the motor. In the motor cooling structure described in Patent Document 1, since the refrigerant discharge port is provided only in one end plate, the refrigerant sprays only on one coil end of the coil ends at both axial ends of the stator core. It is done. Therefore, the other coil end is not cooled, and the stator coil cannot be sufficiently cooled.

  On the other hand, in the motor cooling structure described in Patent Document 2, it is necessary to extend at least the axial refrigerant path in the axial direction of the shaft to the vicinity of the central portion in the axial direction of the shaft, and a long refrigerant flow path must be provided in the shaft. I must. Therefore, the length of drilling required to provide the coolant channel in the shaft also increases, and the processing cost increases.

  In view of the above problems, an object of the present invention is to provide a rotating electrical machine that can sufficiently cool the coil ends at both ends in the axial direction of the rotor and the stator core and that can be easily processed when providing the refrigerant flow path. .

  According to one aspect of the present invention, a rotor including a shaft, a rotor core to which the shaft is attached, and first and second end plates provided on both end surfaces in the axial direction of the rotor core, and the rotor are disposed so as to surround the rotor. A rotating electric machine is provided. The rotating electrical machine is formed in a rotor core, a first flow path provided on a shaft, linearly extending from an end surface near the first end plate, and extending toward the first end plate, Second and third flow paths for flowing the refrigerant from the end face on the first end plate side toward the end face on the second end plate side, and formed in the rotor core, from the end face on the second end plate side toward the end face on the first end plate side. A fifth flow path formed in the first end plate, connected to the first flow path and the third flow path, and connected to the first flow path and the third flow path. And a U-turn flow path formed in the second end plate and connecting the third flow path and the fourth flow path. The first end plate is formed with a first discharge port that discharges the refrigerant that has passed through the fourth flow path to the outside of the rotor, and the second end plate has the refrigerant that has passed through the second flow path outside of the rotor. A second discharge port for discharging is formed.

  According to the present invention, the cooling oil supplied from the first flow path of the shaft to the second flow path is sprayed from the first discharge port to the coil end by hydraulic pressure. On the other hand, the cooling oil supplied from the first flow path of the shaft to the third flow path is U-turned by the U-turn flow path, flows through the fourth flow path in the direction opposite to the second flow path, and is discharged to the second discharge port. Sprayed to the coil end by hydraulic pressure. Thereby, the coil ends at both axial ends of the rotor and the stator core can be sufficiently cooled. Moreover, the 1st flow path formed in the shaft is extended toward the 1st end plate, after extending linearly from the end surface near the 1st end plate of a shaft. For this reason, the 1st flow path in a shaft is comprised short. Thereby, the length of the drill process for providing the flow path in a shaft can be shortened, and processing cost can be reduced.

FIG. 1 is a schematic configuration diagram illustrating a motor according to the first embodiment. FIG. 2 is a radial sectional view of the first end plate as viewed from the axial direction of the motor. FIG. 3 is a radial sectional view of the second end plate as viewed from the axial direction of the motor. FIG. 4 is a partial cross-sectional view in the radial direction of the rotor core as seen from the axial direction of the motor. FIG. 5 is a schematic configuration diagram of an axial cross section of the cooling oil passage. FIG. 6 is a partial cross-sectional view in the radial direction of the rotor core as seen from the axial direction in a motor according to a modification of the first embodiment. FIG. 7 is a partial cross-sectional view in the radial direction of the rotor core as seen from the axial direction in a motor according to a modification of the first embodiment. FIG. 8 is a partial cross-sectional view in the radial direction of the rotor core as seen from the axial direction in the motor according to the modification of the first embodiment. FIG. 9 is a partial cross-sectional view in the radial direction of the rotor core as seen from the axial direction in a motor according to a modification of the first embodiment. FIG. 10 is a partial cross-sectional view in the radial direction of the rotor core viewed from the axial direction in the motor according to the second embodiment. FIG. 11 is a partial cross-sectional view in the radial direction of the rotor core as seen from the axial direction in a motor according to a modification of the second embodiment. FIG. 12 is a partial cross-sectional view in the radial direction of the rotor core viewed from the axial direction in the motor according to the third embodiment. FIG. 13 is a partial cross-sectional view in the radial direction of the rotor core as seen from the axial direction in the motor according to the fourth embodiment. FIG. 14 is a partial cross-sectional view in the radial direction of the rotor core as seen from the axial direction in a motor according to a modification of the fourth embodiment. FIG. 15 is a partial cross-sectional view in the radial direction of the rotor core as seen from the axial direction in the motor according to the fifth embodiment. FIG. 16 is a partial cross-sectional view in the radial direction of the rotor core as seen from the axial direction in a motor according to a modification of the fifth embodiment. FIG. 17 is a partial cross-sectional view in the radial direction of the rotor core as seen from the axial direction in a motor according to a modification of the fifth embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a schematic configuration diagram showing a motor 1 according to the first embodiment of the present invention. A motor 1 shown in FIG. 1 functions as an electric motor that rotates by receiving power supplied from a power source such as a battery and drives wheels of a vehicle. The motor 1 also functions as a generator that is driven by an external force to generate power. Therefore, the motor 1 is configured as a so-called rotating electric machine (motor generator) that functions as an electric motor and a generator. The motor 1 may be used as a drive source for a system other than the vehicle, not a motor for driving the vehicle.

  As shown in FIG. 1, the motor 1 includes a rotor 10 and a stator 20 disposed on the outer peripheral side of the rotor 10. The rotor 10 and the stator 20 are accommodated in a case (not shown).

  The rotor 10 is disposed inside the stator 20 so as to be rotatable with respect to the stator 20. The rotor 10 includes a shaft 11 as a rotating shaft, a rotor core 12 that is a cylindrical member formed by laminating a plurality of electromagnetic steel plates, and ring-shaped first portions provided on both axial end surfaces of the rotor core 12. 1 and second end plates 13, 14. The shaft 11 is rotatably supported by bearings 15 and 16 provided in the case. The rotor core 12 is fastened to the shaft 11 by, for example, press-fitting the shaft 11 into a part of the inner peripheral surface. The inner peripheral surfaces of the first and second end plates 13 and 14 are in contact with the outer peripheral surface of the shaft 11, and are fixed to the shaft 11 on both end surfaces in the axial direction of the rotor core 12 by, for example, contraction fastening. Yes. The first and second end plates 13, 14 prevent the magnet 17, which will be described later, from jumping out.

  The stator 20 includes a stator core 21 that is a cylindrical member formed by laminating a plurality of electromagnetic steel plates, and a stator coil that is wound around the teeth of the stator core 21. An end portion of the wound stator coil (hereinafter referred to as a coil end 22) protrudes outward of the stator core 21 in the axial direction of the motor 1. The outer peripheral surface of the stator core 21 is fixed to the case in surface contact with the inner peripheral surface of the case.

  On one side in the axial direction of the shaft 11, a resolver rotor 18 installed on the outer periphery of the shaft 11 is provided outside the bearings 15 and 16 in the axial direction. The resolver rotor 18 rotates integrally with the shaft 11 and is provided to detect the rotation angle of the rotor 10.

  A plurality of (for example, eight) holes 171 for accommodating the magnets 17 are formed in the axial direction at positions from the outer periphery of the rotor core 12, and the magnets 17 are inserted into the holes 171.

  Next, the cooling oil passage (refrigerant passage) 30 provided in the rotor 10 will be described with reference to FIGS.

  The cooling oil passage 30 in the rotor 10 includes first to fifth passages 31 to 35, a U-turn passage 37, and first and second discharge ports 36 and 38, and cools the inside of the cooling oil passage 30. As the oil flows, the motor 1 is cooled.

  As shown in FIG. 1, the first flow path 31 is formed in the shaft 11, extends linearly from the end surface of the shaft 11 on the side close to the first end plate 13, and then faces the first end plate 13. Branching into two and extending. The first flow path 31 is connected to an oil pump (not shown) outside the rotor 10, and cooling oil is supplied from the oil pump. In the present embodiment, the first flow path 31 is branched into two, but is not limited thereto. For example, the first flow path 31 may be extended toward the first end plate 13 without branching, or may be branched into three or more and each extended toward the first end plate 13. It may be.

  Four second flow paths 32 are formed in the rotor core 12 and extend from the one axial end surface of the rotor core 12 to the other end surface, for example, linearly in the axial direction of the motor 1. When cooling oil flows through the second flow path 32, the rotor core 12 and the magnet 17 fitted to the rotor core 12 are cooled.

  A part of the inner peripheral surface of the third flow path 33 is constituted by the outer peripheral surface of the shaft 11, and eight third flow paths 33 are formed at positions on the inner peripheral side of the second flow path 32 of the rotor core 12. The third flow path 33 extends from the one end surface in the axial direction of the rotor core 12 to the other end surface, for example, linearly in the axial direction of the motor 1.

  Four fourth flow paths 34 are formed in the rotor core 12, and extend from the one end surface in the axial direction of the rotor core 12 to the other end surface, for example, linearly in the axial direction of the motor 1. The fourth flow path 34 is formed at a position where the distance from the central axis of the rotor core 12 to the second flow path 32 is equal to the distance from the central axis of the rotor core 12 to the fourth flow path 34. When cooling oil flows through the fourth flow path 34, the rotor core 12 and the magnet 17 fitted to the rotor core 12 are cooled.

  The fifth flow path 35 is formed along the outer peripheral surface of the shaft 11 at a position in contact with one end surface of the rotor core 12 of the first end plate 13. The inner peripheral surface of the fifth flow path 35 is configured by the outer peripheral surface of the shaft 11, and the bottom 350 is configured by the end surface of the rotor core 12. The fifth flow path 35 is connected to the first flow path 31 on the inner peripheral surface of the first end plate 13 (the outer peripheral surface of the shaft 11), and is connected to the second flow path 32 and the third flow path 33 at the bottom 350. is doing. That is, the fifth flow path 35 connects the first flow path 31 and the second flow path 32, and connects the first flow path 31 and the third flow path 33.

  The U-turn flow path 37 is formed along the outer peripheral surface of the shaft 11 at a position in contact with the other end surface of the rotor core 12 of the second end plate 14. The inner peripheral surface of the U-turn channel 37 is configured by the outer peripheral surface of the shaft 11, and the upper portion 370 is configured by the end surface of the rotor core 12. The U-turn flow path 37 is connected to the third flow path 33 and the fourth flow path 34 at the upper portion 370. That is, the U-turn flow path 37 connects the third flow path 33 and the fourth flow path 34.

  Four first discharge ports 36 are formed on the second end plate 14, and from the end surface (the upper end surface of the second end plate 14) that contacts the rotor core 12 of the second end plate 14 to the other end surface (of the second end plate 14). It extends to the lower end surface. The first discharge port 36 is connected to each of the four second flow paths 32 at the upper end surface of the second end plate 14, and is opened toward the outside of the rotor 10 at the lower end surface of the second end plate 14. An opening 361 is provided.

  Four second discharge ports 38 are formed on the first end plate 13, and from the end surface (lower end surface of the first end plate 13) that contacts the rotor core 12 of the first end plate 13 to the other end surface (of the first end plate 13). (Upper end surface). The second discharge ports 38 are respectively connected to the four fourth flow paths 34 at the lower end surface of the first end plate 13, and are opened toward the outside of the rotor 10 at the upper end surface of the first end plate 13. An opening 381 is provided.

  FIG. 2 is a radial cross-sectional view of the first end plate 13 as viewed from the axial direction of the motor 1. As shown in FIG. 2, the fifth flow path 35 includes an inner peripheral part 351 and a connecting part 352. The inner peripheral portion 351 is formed so as to surround the outer peripheral surface of the shaft 11, and is connected to the first flow path 31 on the outer peripheral surface of the shaft 11. Further, the inner peripheral portion 351 is connected to the eight third flow paths 33 in contact with the outer peripheral surface of the shaft 11 at the bottom 350 of the fifth flow path 35. The connecting part 352 extends from the inner peripheral part 351 toward each of the four second flow paths 32 formed on the outer peripheral side of the third flow path 33, and is connected to the second flow path 32. Yes. As described above, the fifth flow path 35 connects the first flow path 31 and the eight third flow paths 33 via the inner peripheral portion 351, and the first flow path via the inner peripheral portion 351 and the connecting portion 352. The flow path 31 and the four second flow paths 32 are connected. Note that the configuration of the fifth flow path 35 is not limited to the above, and it is sufficient that the first flow path 31 is connected to the second flow path 32 and the third flow path 33.

  FIG. 3 is a radial sectional view of the second end plate 14 as viewed from the axial direction of the motor 1. As shown in FIG. 3, the U-turn flow path 37 includes an inner peripheral part 371 and a connecting part 372. The inner peripheral portion 371 is formed so as to surround the outer peripheral surface of the shaft 11, and the inner peripheral portion 371 has eight third flow paths 33 in contact with the outer peripheral surface of the shaft 11 in the upper portion 370 of the U-turn flow path 37. Connected. The connecting part 372 extends from the inner peripheral part 371 toward each of the four fourth flow paths 34 formed on the outer peripheral side of the third flow path 33, and is connected to the fourth flow path 34. Yes. As described above, the U-turn flow path 37 connects the eight third flow paths 33 and the four fourth flow paths 34 via the inner peripheral portion 371 and the connecting portion 372. Note that the configuration of the U-turn flow path 37 is not limited to the above, and it may be formed so as to connect the third flow path 33 and the fourth flow path 34. For example, a configuration may be adopted in which four U-turn channels 37 that connect two third channels 33 and one fourth channel 34 are provided.

  According to the cooling oil passage 30 configured as described above, the cooling oil supplied to the first flow path 31 by the oil pump flows into the fifth flow path 35 from the outer peripheral surface of the shaft 11. The cooling oil that has flowed into the fifth flow path 35 is transferred to the third flow path 33 via the inner peripheral portion 351 of the fifth flow path 35, and to the second flow path 32 via the inner peripheral portion 351 and the connecting portion 352. Supplied respectively. The cooling oil supplied to the second flow path 32 flows into the first discharge port 36 from the upper end surface of the second end plate 14 and is discharged out of the rotor from the opening 361 on the lower end surface of the second end plate 14. . The cooling oil discharged from the opening 361 is sprayed on one coil end 22a by the hydraulic pressure, and cools the coil end 22a. On the other hand, the cooling oil supplied to the third flow path 33 flows into the U-turn flow path 37 from the upper portion 370 of the second end plate 14. The cooling oil that has flowed into the U-turn flow path 37 is supplied so as to make a U-turn from the connecting portion 372 to the fourth flow path 34 via the inner peripheral portion 371 of the U-turn flow path 37. The cooling oil supplied to the fourth flow path 34 flows into the second discharge port 38 from the lower end surface of the first end plate 13 and is discharged from the opening 381 on the upper end surface of the first end plate 13 to the outside of the rotor. . The cooling oil discharged from the opening 381 is sprayed to the other coil end 22b by the hydraulic pressure, and cools the coil end 22b.

  As described above, the cooling oil passage 30 includes the route from the first flow passage 31 to the fifth flow passage 35, the second flow passage 32, and the first discharge port 36, and the first flow passage 31 to the fifth flow passage 35, There are two types of routes, a route that flows through the third flow path 33, the U-turn flow path 37, the fourth flow path 34, and the second discharge port 38.

  FIG. 4 is a partial cross-sectional view in the radial direction of the rotor core 12 as viewed from the axial direction of the motor 1. As shown in FIG. 4, a hole 171 into which the magnet 17 is inserted, a second flow path 32, a third flow path 33, and a fourth flow path 34 are formed in the rotor core 12.

  The hole 171 into which the magnet 17 is inserted is formed at a position near the outer periphery of the rotor core 12, and the two holes 171 are provided so as to form a substantially V shape. Two magnets 17 constitute one magnetic pole, and the magnetic poles formed by the two magnets 17 are equidistant from each other along the circumferential direction of the rotor core 12, and the polarities of the adjacent magnetic poles are different from each other. Has been placed. A straight line connecting the center of one magnetic pole formed by the two magnets 17 and the rotation center of the rotor 10 is a d-axis, and a direction electrically orthogonal to the d-axis is a q-axis.

  The magnet 17 is formed with a width in the longitudinal direction smaller than that of the hole 171, and flux barriers 172 as space portions are formed at both ends in the circumferential direction of the hole 171. This space portion has a lower magnetic permeability and a higher magnetic resistance than the electromagnetic steel sheet. Therefore, the flux barrier 172 acts as a magnetic barrier in which the magnetic flux hardly passes in the magnetic circuit that the magnet 17 forms on the rotor core 12.

  The third flow path 33 is formed in a substantially semicircular shape (bow shape) in the radial cross-sectional view of the rotor core 12, and 2 for each magnetic pole on the inner peripheral side of the second flow path 32 and the fourth flow path 34. The books are arranged one by one. A part of the inner peripheral surface of the third flow path 33 is constituted by the outer peripheral surface of the shaft 11. In the rotor core 12, the shaft 11 is press-fitted into a part of the inner peripheral surface and fastened to the shaft 11. However, the third flow path 33 is formed in a portion of the inner peripheral surface of the rotor core 12 that does not have a press-fitting function. ing. In the present embodiment, a part of the inner peripheral surface of the third flow path 33 is configured by the outer peripheral surface of the shaft 11. However, the present invention is not limited to this, and the third flow path 33 is not in contact with the shaft 11. May be formed. Moreover, in this embodiment, although the 3rd flow path 33 is formed in the substantially semicircle shape (bow shape), the shape of the 3rd flow path 33 is not restricted to this.

  The second flow path 32 and the fourth flow path 34 have an elliptical shape in the radial sectional view of the rotor core 12, and are formed in the vicinity of the hole 171 on the outer peripheral side of the third flow path 33, one for each magnetic pole. In addition, the magnetic poles formed by the two magnets 17 are arranged at positions symmetrical with respect to the d-axis. That is, the second flow path 32 and the fourth flow path 34 are formed in line symmetry with respect to the d axis at a position closer to the magnet 17 than the third flow path 33.

  FIG. 5 is a schematic configuration diagram of an axial cross section of the cooling oil passage 30.

  As shown in FIG. 5, the second flow path 32 and the fourth flow path 34 have the same radial cross-sectional area and a smaller radial cross-sectional area than the third flow path 33. Since the flow rate of the refrigerant flowing through the flow path is inversely proportional to the cross-sectional area of the flow path, the flow rate of the cooling oil flowing through the second flow path 32 and the fourth flow path 34 having a smaller radial cross-sectional area than the third flow path 33 is The flow velocity of the cooling oil flowing through the third flow path 33 is faster. Further, since the heat transfer coefficient is proportional to the flow velocity, the cooling efficiency by the cooling oil flowing through the second flow path 32 and the fourth flow path 34 is substantially equal.

  According to the motor 1 of the first embodiment described above, the following effects can be obtained.

  The motor 1 (rotating electrical machine) includes a second flow path 32, a third flow path 33, and a fourth flow path 34 in the rotor core 12. The second flow path 32 is connected to the first discharge port 36, the third flow path 33 is connected to the fourth flow path 34 by the U-turn flow path 37, and the fourth flow path 34 is connected to the second discharge port 38. . For this reason, the cooling oil that has flowed through the second flow path 32 is sprayed from the opening 361 of the first discharge port 36 to the coil end 22 a by hydraulic pressure. On the other hand, the cooling oil that has flowed through the third flow path 33 is U-turned by the U-turn flow path 37, flows through the fourth flow path 34 in the direction opposite to the second flow path 32, and opens the second discharge port 38. It is sprayed from the coil 381 to the coil end 22b by hydraulic pressure. Thereby, coil end 22a, 22b of the axial direction both ends of the rotor 10 and the stator core 21 can fully be cooled.

  The motor 1 extends toward the first end plate 13 after the first flow path 31 formed in the shaft 11 extends linearly from the end surface of the shaft 11 near the first end plate 13. ing. For this reason, the 1st flow path 31 in the shaft 11 is comprised short. Thereby, the length of the drill process at the time of providing the flow path in the shaft 11 can be shortened, and the processing cost can be reduced. In addition, when the drilling length is increased, it is necessary to use a thicker drill, the diameter of the flow path in the shaft 11 is increased, and the rotation detector provided on the shaft 11 must be a large one. I will have to. On the other hand, since the motor 1 of this embodiment has a short drilling length, it can be processed by a thin drill and a thinner shaft 11 can be used. Therefore, the resolver rotor 18 can also be small, and space saving and cost reduction can be achieved.

  In the motor 1, the first end plate 13 is provided with a fifth flow path 35 that connects the first flow path 31 formed on the shaft 11 and the second and third flow paths 32 and 33 formed on the rotor core 12. ing. Since the rotor core is generally configured by laminating electromagnetic steel plates, when a radial flow path is provided in the rotor core 12 and the flow path of the shaft 11 and the flow path of the rotor core 12 are connected, the processing becomes complicated. That is, when providing radial flow paths in the rotor core 12, some laminated steel sheets are provided with axial and radial flow paths, and some laminated steel sheets are provided with only axial flow paths, Processing to laminated steel sheets cannot be performed at once. On the other hand, in the motor 1 of the present embodiment, since the radial flow path connecting the flow path of the shaft 11 and the flow path of the rotor core 12 is provided in the first end plate 13, the radial flow path is provided in the rotor core 12. Compared with the case of providing, processing to the rotor core 12 is easy.

  In the motor 1, the second flow path 32 and the fourth flow path 34 in which cooling oil flows in opposite directions in the axial direction are arranged at positions symmetrical with respect to the d-axis. As a result, the magnets 17 can be cooled uniformly, and adverse effects such as only a part of the magnets 17 not being cooled can be prevented.

  In the motor 1, the radial cross-sectional areas of the second flow path 32 and the fourth flow path 34 are equal. For this reason, the flow rates of the refrigerant flowing through the second flow path 32 and the fourth flow path 34 are equal, and the thermal conductivities in the second flow path 32 and the fourth flow path 34 are also substantially equal. Therefore, the cooling efficiency by the cooling oil flowing through the second flow path 32 and the fourth flow path 34 becomes substantially equal, and the magnet 17 can be cooled uniformly. Further, by arranging the second flow path 32 and the fourth flow path 34 symmetrically and having the same cross-sectional area, the internal stress of the rotor 10 is generated symmetrically and equally, so that the balance during rotation of the rotor is improved.

  Further, the motor 1 has a radial cross-sectional area of the second flow path 32 and the fourth flow path 34 smaller than a radial cross-sectional area of the third flow path 33, and the second flow path 32 and the fourth flow path 34 are It is formed at a position closer to the magnet 17 than the third flow path 33. The flow rate of the refrigerant flowing through the flow path is faster in the second flow path 32 and the fourth flow path 34 than in the third flow path 33 with a smaller radial cross-sectional area, and the heat of the second flow path 32 and the fourth flow path 34 is increased. The transmission rate is higher than that of the third flow path 33. That is, the cooling efficiency by the second flow path 32 and the fourth flow path 34 is higher than that of the third flow path 33. Thus, since the 2nd flow path 32 and the 4th flow path 34 with high cooling efficiency are formed in the position nearer to the magnet 17 than the 3rd flow path 33, the cooling efficiency of the magnet 17 improves.

  In the present embodiment, eight magnets 17, four second flow paths 32, eight third flow paths 33, and four fourth flow paths 34 are formed. The number of is not limited to these.

  Moreover, in this embodiment, although the magnet 17 is arrange | positioned so that a substantially V shape may be made, arrangement | positioning of the magnet 17 is not restricted to this.

(Modification of the first embodiment)
A motor 1 according to a modification of the first embodiment will be described with reference to FIG.

  FIG. 6 is a partial cross-sectional view in the radial direction of the rotor core 12 as seen from the axial direction in the motor 1 according to the modification of the first embodiment. As shown in FIG. 6, in the present modification, the second flow path 32 and the fourth flow path 34 are arranged at positions symmetrical with respect to the q axis.

  Even with such a configuration, the magnets 17 can be uniformly cooled, and adverse effects such as only a part of the magnets 17 not being cooled can be prevented.

  In the first embodiment and its modifications, the second flow path 32 and the fourth flow path 34 have an elliptical shape, but the shape of the flow path is not limited to this. For example, as shown in FIG. 7, the second flow path 32 and the fourth flow path 34 may have a round shape in the radial cross-sectional view of the rotor core 12, and have a long hole shape as shown in FIG. 8. Alternatively, it may have a square hole shape as shown in FIG. Similarly, in the second and third embodiments described later, the shape of the flow path can be freely changed.

(Second Embodiment)
The motor 1 according to the second embodiment will be described with reference to FIG.

  FIG. 10 is a partial cross-sectional view in the radial direction of the rotor core 12 as seen from the axial direction in the motor 1 according to the second embodiment. In the second embodiment, the arrangement and number of the second flow paths 32 and the fourth flow paths 34 are different from those in the first embodiment. In the following embodiments, the same functions as those in the first embodiment are denoted by the same reference numerals, and repeated description will be omitted as appropriate.

  As shown in FIG. 10, in the present embodiment, two second flow paths 32 are formed for each magnetic pole, and the two second flow paths 32 are positioned equidistant from the central axis of the rotor core 12. In addition, they are arranged symmetrically with respect to the d axis. Two fourth flow paths 34 are formed for each magnetic pole, and the two fourth flow paths 34 are located on the inner peripheral side of the second flow path 32 and equidistant from the central axis of the rotor core 12. In addition, they are arranged symmetrically with respect to the d axis.

  Even with such a configuration, the magnets 17 can be uniformly cooled, and adverse effects such as only a part of the magnets 17 not being cooled can be prevented.

  In the present embodiment, two second flow paths 32 and four fourth flow paths 34 are formed for each magnetic pole, but the number of second flow paths 32 and fourth flow paths 34 is not limited to this. For example, as shown in FIG. 11, four poles may be formed for each magnetic pole, and each may be formed symmetrically with respect to the d-axis.

  In the present embodiment, the plurality of second flow paths 32 and the plurality of fourth flow paths 34 are arranged symmetrically with respect to the d axis, respectively. The four flow paths 34 may be arranged symmetrically with respect to the q axis.

  In the present embodiment, the fourth flow path 34 is disposed on the inner peripheral side with respect to the second flow path 32, but the present invention is not limited to this, and the fourth flow path 34 is on the outer peripheral side with respect to the second flow path 32. It may be arranged.

(Third embodiment)
The motor 1 according to the third embodiment will be described with reference to FIG.

  FIG. 12 is a partial cross-sectional view in the radial direction of the rotor core 12 as seen from the axial direction in the motor 1 according to the third embodiment. The third embodiment is different from the other embodiments in that the second flow path 32 and the fourth flow path 34 are formed on the d-axis and the q-axis.

  As shown in FIG. 12, one second flow path 32 is formed on each of the d-axis and the q-axis. One fourth flow path 34 is formed on the d-axis and one q-axis on the inner peripheral side of the second flow path 32.

  Even with such a configuration, the same effects as those of the first embodiment described above can be obtained.

  In the present embodiment, one second channel 32 and one fourth channel 34 are formed on the d-axis and the q-axis, respectively, but the number of channels is not limited to this, and the d-axis and the q-axis are not limited to this. Two or more of each may be formed on the shaft.

  In the present embodiment, the fourth flow path 34 is disposed on the inner peripheral side with respect to the second flow path 32, but the present invention is not limited to this, and the fourth flow path 34 is on the outer peripheral side with respect to the second flow path 32. It may be arranged.

(Fourth embodiment)
With reference to FIG. 13, the motor 1 by 4th Embodiment is demonstrated.

  FIG. 13 is a partial cross-sectional view in the radial direction of the rotor core 12 as seen from the axial direction in the motor 1 according to the fourth embodiment. The fourth embodiment is different from the third embodiment in that the second flow path 32 and the fourth flow path 34 are formed only on the d-axis.

  As shown in FIG. 13, the second flow path 32 has an elliptical shape in the radial sectional view of the rotor core 12, and one second flow path 32 is formed in the vicinity of the magnet 17 on the d axis for each magnetic pole. Further, the fourth flow path 34 has an elliptical shape in the radial cross-sectional view of the rotor core 12, and one fourth flow path 34 is formed for each magnetic pole on the inner peripheral side of the second flow path 32 on the d axis.

  Even with such a configuration, the same effects as those of the first embodiment described above can be obtained.

  In the present embodiment, one second flow path 32 and one fourth flow path 34 are formed on the d-axis, but the number of flow paths is not limited to this, and two each on the d-axis. It may be formed as described above.

  In the present embodiment, the fourth flow path 34 is formed on the inner peripheral side with respect to the second flow path 32, but the fourth flow path 34 is in the vicinity of the magnet 17 on the d-axis, and the second flow path 32. May be formed on the inner peripheral side of the fourth flow path 34 on the d-axis.

  In the present embodiment, the second flow path 32 and the fourth flow path 34 are formed only on the d-axis. However, the present invention is not limited to this, and the second flow path 32 and the fourth flow path 34 are on the q-axis. It may be formed only.

  In the present embodiment, the second flow path 32 and the fourth flow path 34 have an elliptical shape in the radial cross-sectional view of the rotor core 12, but the shape of the flow path is not limited to this, for example, as shown in FIG. As described above, the second flow path 32 and the fourth flow path 34 may be rectangular in the radial cross-sectional view of the rotor core 12.

(Fifth embodiment)
With reference to FIG. 15, a motor 1 according to a fifth embodiment will be described.

  FIG. 15 is a partial cross-sectional view in the radial direction of the rotor core 12 as seen from the axial direction in the motor 1 according to the fifth embodiment. The fifth embodiment is different from the other embodiments in that the flux barrier 172 is the second flow path 32 and the fourth flow path 34.

  As shown in FIG. 15, the flux barriers 172 a and 172 c formed at the ends near the d-axis of the two holes 171 into which the two magnets 17 constituting one magnetic pole are inserted are the second flow paths 32. It is utilized as. Further, the flux barriers 172b and 172d formed at the ends close to the q-axis of the two holes 171 into which the two magnets 17 constituting one magnetic pole are inserted are used as the fourth flow path 34. Since the two holes 171 in which the flux barriers 172 are formed at both ends are arranged symmetrically with respect to the d-axis and two for each magnetic pole, the second flow path 32 and the fourth flow path 34 are also two for each magnetic pole. Are symmetrical with respect to the d axis.

  According to the motor 1 of the fifth embodiment described above, the following effects can be obtained in addition to the effects obtained by the motor 1 of the first embodiment.

  The motor 1 uses the flux barriers 172 formed at both ends of the magnet 17 as the second flow path 32 and the fourth flow path 34. In the motor 1 configured as described above, the cooling efficiency of the magnet 17 is improved because the second flow path 32 and the fourth flow path 34 through which the cooling oil flows are in contact with the magnet 17. Further, since the flux barrier 172 is used as a cooling flow path, it is not necessary to provide a separate cooling flow path in the rotor core 12, and adverse effects on the rotor core strength can be reduced.

  In addition, the second flow path 32 and the fourth flow path 34 are arranged symmetrically with respect to each other across the d-axis, two for each magnetic pole. Therefore, the magnets 17 can be uniformly cooled, and adverse effects such as the fact that only some of the magnets 17 are not cooled can be prevented.

  In the present embodiment, the second flow path 32 is formed in the flux barriers 172a and 172c on the side close to the d axis, and the fourth flow path 34 is formed in the flux barriers 172b and 172d on the side close to the q axis. It is not limited to this. As shown in FIG. 16, the fourth flow path 34 may be formed in the flux barriers 172a and 172c near the d axis, and the second flow path 32 may be formed in the flux barriers 172b and 172d near the q axis.

(Modification of the fifth embodiment)
A motor 1 according to a modification of the fifth embodiment will be described with reference to FIG.

  FIG. 17 is a partial cross-sectional view in the radial direction of the rotor core 12 as seen from the axial direction in the motor 1 according to the modification of the fifth embodiment. As shown in FIG. 17, flux barriers 172 a and 172 b formed at both ends of one of the two magnets 17 constituting one magnetic pole are utilized as the second flow path 32. Further, of the two magnets 17 constituting one magnetic pole, flux barriers 172 c and 172 d formed at both ends of the other magnet 17 are utilized as the fourth flow path 34. The second flow path 32 and the fourth flow path 34 are formed symmetrically with respect to the d axis.

  Even with such a configuration, the same effects as those of the fifth embodiment described above can be obtained.

  The embodiment of the present invention has been described above. However, the above embodiment only shows a part of application examples of the present invention, and the technical scope of the present invention is limited to the specific configuration of the above embodiment. Absent.

  In any of the embodiments, the refrigerant flowing through the refrigerant flow path 30 is the cooling oil, but the refrigerant is not limited to this, and may be a gas such as nitrogen gas.

  Each of the above embodiments has been described as a single embodiment, but may be combined as appropriate.

DESCRIPTION OF SYMBOLS 1 Motor 10 Rotor 11 Shaft 12 Rotor core 13 1st end plate 14 2nd end plate 20 Stator 21 Stator core 22 Coil end 30 Cooling oil path 31 1st flow path 32 2nd flow path 33 3rd flow path 34 4th flow path 35 Fifth flow path 36 First discharge port 37 U-turn flow path 38 Second discharge port 172 Flux barrier

Claims (8)

A rotor including a shaft, a rotor core to which the shaft is attached, a plurality of permanent magnets fitted to the rotor core, and first and second end plates provided on both end surfaces in the axial direction of the rotor core;
A rotating electric machine comprising a stator arranged so as to surround the rotor,
A first flow path provided on the shaft and extending linearly from an end surface near the first end plate and then extending toward the first end plate;
Formed in the rotor core, and second and third flow paths for flowing a refrigerant from an end surface on the first end plate side toward an end surface on the second end plate side;
A fourth flow path formed in the rotor core and configured to flow a refrigerant from an end surface on the second end plate side toward an end surface on the first end plate side;
A fifth flow path formed on the first end plate, connecting the first flow path and the second flow path, and connected to the first flow path and the third flow path;
A U-turn flow path formed on the second end plate and connecting the third flow path and the fourth flow path;
The first end plate is formed with a first discharge port for discharging the refrigerant that has passed through the fourth flow path to the outside of the rotor,
The second end plate is formed with a second discharge port for discharging the refrigerant that has passed through the second flow path to the outside of the rotor.
Rotating electric machine. One or a plurality of the second and fourth flow paths are formed for each magnetic pole,
A plurality of the third flow paths are formed for each magnetic pole.
The rotating electrical machine according to claim 1. The second flow path and the fourth flow path are arranged symmetrically with respect to the d axis constituting one magnetic pole or the q axis electrically orthogonal to the d axis.
The rotating electrical machine according to claim 1 or 2, characterized in that A plurality of the second and fourth flow paths are formed for each magnetic pole,
A plurality of the third flow paths are formed for each magnetic pole,
Each of the plurality of second flow paths is arranged in line symmetry with respect to the d axis formed by the adjacent second flow path and one magnetic pole or the q axis electrically orthogonal to the d axis. Each of the fourth flow paths is arranged symmetrically with respect to the adjacent fourth flow path across the d axis or the q axis.
The rotating electrical machine according to claim 1. The third flow path is disposed closer to the inner periphery of the rotor core than the second flow path and the fourth flow path.
The rotating electrical machine according to any one of claims 1 to 4, wherein The radial cross-sectional areas of the second flow path and the fourth flow path are equal and smaller than the radial cross-sectional area of the third flow path,
The rotating electrical machine according to any one of claims 1 to 5, wherein The second flow path and the fourth flow path are formed at positions closer to the permanent magnet than the third flow path,
The rotating electrical machine according to any one of claims 1 to 6, wherein The rotor core includes a plurality of holes in which a plurality of permanent magnets are fitted and flux barriers are formed at both end portions,
The flux barrier constitutes the second flow path and the fourth flow path.
The rotating electrical machine according to any one of claims 1 to 7, wherein

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