JP2024035947A - Rotary electric machine - Google Patents

Abstract

To provide a rotary electric machine capable of increasing motor efficiency by appropriately cooling a permanent magnet.SOLUTION: A cylindrical part 21 has a radial through-hole 241 penetrating from the inner peripheral surface of a recess 24 to a permanent magnet 22 in a radial direction, an axial through-hole 242 penetrating from one end 20a side of the permanent magnet 22 to the other end 20b side in an axial direction, and an opening 243 open at the other end 20b of the axial through-hole 242. A housing 10 is provided with a pedestal 12 that rotatably supports a rotary shaft. The pedestal 12 is provided with a refrigerant inlet 14 for introducing a refrigerant into the housing 10. The refrigerant introduced from the refrigerant inlet 14 is distributed from the recess 24 through the radial through-hole 241 and the axial through-hole 242 to the opening 243.SELECTED DRAWING: Figure 1

Description

The present invention relates to a rotating electrical machine.

Since a rotating electrical machine generates heat during its operation, it is necessary to appropriately cool the stator and rotor. Normally, the stator can be cooled by providing a coolant flow path in a yoke or housing surrounding the stator. On the other hand, since the rotor is constantly rotating, it is difficult to provide a coolant flow path, and cooling requires some ingenuity.

In Patent Document 1, an oil reservoir is disposed inside the rotor in the radial direction in which permanent magnets are embedded, and the oil (refrigerant) stored in the oil reservoir is transferred to the inner circumference of the cylindrical portion by centrifugal force caused by the rotation of the rotor. A configuration is disclosed in which the cylindrical portion is cooled by scattering the liquid toward the cylindrical portion.

JP2008-289245A

With a configuration in which the refrigerant is scattered toward the inner circumference of the rotor by centrifugal force as in the prior art, it is not possible to directly cool the permanent magnets embedded in the rotor. Therefore, since the permanent magnets are not cooled sufficiently, there is a problem in that there is a limit to improving motor efficiency.

An object of the present invention is to provide a rotating electrical machine that can improve motor efficiency by appropriately cooling permanent magnets installed in a rotor.

One aspect of the present invention is applied to a rotating electric machine that includes a rotor, a stator provided on the outer periphery of the rotor, and a housing that accommodates the rotor and the stator. The rotor includes a rotating shaft, a cylindrical cylindrical portion including a permanent magnet, and a connecting portion connecting the outer circumferential surface of the rotating shaft and the inner circumferential surface of the cylindrical portion. The rotor is a space formed by a rotating shaft, a cylindrical portion, and a connecting portion, and includes an annular recess that opens in the axial direction across the connecting portion. The housing includes a pedestal that rotatably supports the rotating shaft. The pedestal is provided with a refrigerant introduction hole that introduces the refrigerant toward the annular recess. The rotor has a radial through hole that radially penetrates the cylindrical part in the annular recess, and an axial through hole that communicates with the radial through hole and axially penetrates the inside of the rotor. The coolant introduced into the permanent magnet cools the permanent magnet by passing through the radial through hole and the axial through hole.

According to the present invention, the refrigerant introduced into the annular recess of the rotor from the refrigerant introduction hole of the pedestal flows through the radial through hole and the axial through hole inside the rotor, so that the refrigerant is directed against the permanent magnets provided in the rotor. The refrigerant can be directly circulated through the refrigerant. Thereby, the permanent magnet is appropriately cooled, so that motor efficiency can be improved.

FIG. 1 is an axial cross-sectional view of the motor of this embodiment. FIG. 2 is a perspective view of a rotating shaft and a cylindrical portion that constitute the rotor. FIG. 3 is a perspective view of the rotor with permanent magnets attached thereto. FIG. 4 is a perspective view of the end plate attached to the rotor. FIG. 5 is a radial cross-sectional view of the rotor. FIG. 6 is an axial cross-sectional view of the rotor centered on the annular recess. FIG. 7 is an explanatory diagram showing a refrigerant distribution path. FIG. 8 is an explanatory diagram showing another example of the refrigerant distribution path.

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is an explanatory diagram of a motor 1 as a rotating electric machine according to an embodiment of the present invention, and shows an axial cross-sectional view.

The motor 1 includes a stator 15 formed in an annular shape, a rotor 20 rotatably mounted inside the stator 15, and a housing 10 in which the stator 15 and rotor 20 are housed.

The motor 1 of this embodiment is installed in an electric vehicle or a hybrid vehicle, and functions as an electric motor that drives wheels. The motor 1 also functions as a generator that generates power (regeneration) by receiving driving force from rotation of the wheels. Note that the motor 1 may be used as a drive device for devices other than automobiles, such as various electrical devices or industrial machines.

The stator 15 is constructed by laminating electromagnetic steel sheets. Windings are inserted into slots (not shown) formed in the stator 15. A coil end formed by folding back the winding protrudes from the axial end of the stator 15 . A first coil end 151 projects in the axial direction from one end (left side in FIG. 1) of the stator 15. A second coil end 152 projects in the axial direction from the other end of the stator 15 (on the right side in FIG. 1). By passing current through the windings of the stator 15, the rotor 20 rotates due to the action with the permanent magnets 25 provided in the rotor 20.

The rotor 20 includes a rotating shaft 21, a cylindrical portion 22, and a permanent magnet 25.

The cylindrical portion 22 is a cylindrical member disposed so as to surround the outer periphery of the rotating shaft 21 . The cylindrical portion 22 is arranged coaxially with the rotating shaft 21 . The rotating shaft 21 and the cylindrical portion 22 are connected by a connecting portion 23 that extends in the radial direction from the outer circumferential surface of the rotating shaft 21 and connects to the inner circumferential surface of the cylindrical portion 22 . A permanent magnet 25 having an annular shape is fixed to the outer periphery of the cylindrical portion 22 . A plurality of segment magnets 251, which will be described later with reference to FIG. 4, are arranged in a ring shape so that the permanent magnet 25 has a plurality of magnetic poles in the circumferential direction. The magnetic poles of the permanent magnet 35 are arranged in a Halbach arrangement. The Halbach arrangement is one in which magnetic poles adjacent to each other in the circumferential direction are arranged so that their orientations differ by 90 degrees.

A cylindrical holding member 202 for fixing the permanent magnet 25 is provided on the outer periphery of the permanent magnet 25. Both ends of the permanent magnet 25 in the axial direction are provided with disk-shaped end plates 201 (201a, 201b), respectively.

The rotor 20 has a space formed by the rotating shaft 21, the cylindrical part 22, and the connecting part 23, and has an opening on one end 20a (left side in FIG. 1) in the axial direction across the connecting part 23. An annular recess 24a is formed. Similarly, the other end 20b (right side in FIG. 1) of the rotor 20 is formed by the rotating shaft 21, the cylindrical part 22, and the connecting part 23, and the other axial end with the connecting part 23 separated. An annular recess 24b that opens toward the portion 20b is formed.

The rotating shaft 21 of the rotor 20 is rotatably supported at both ends by bearings 13 (13a, 13b) fixed to a penetrating portion of the inner circumference of the pedestal 12 (12a, 12b) formed in the housing 10. .

The pedestal 12a is formed to protrude from the housing 10 on the one end 20a side of the rotor 20 toward the rotor 20. A portion of the pedestal 12a is formed so as to fit further inside the annular recess 24a than one end 20a of the rotor 20.

Similarly, the pedestal 12b is formed to protrude from the housing 10 on the other end 20b side of the rotor 20 toward the rotor 20, and a part of the pedestal 12b is formed in an annular recess than the other end 20b of the rotor 20. It is formed to fit inside 24b.

The pedestal 12a has a refrigerant introduction hole 14 for introducing refrigerant into the housing. A plurality of coolant introduction holes 14 (for example, eight) are provided along the periphery of the bearing 13a. The refrigerant introduction hole 14 is configured to introduce the refrigerant into the inside of the housing 10, particularly toward the inside of the annular recess 24a of the rotor 20. The refrigerant is, for example, insulating oil, but may also be water such as cooling water, other fluids, or gases.

A radial through hole 241 having a circular cross section is formed in the annular recess 24a of the rotor 20, and extends from the inner wall of the annular recess 24a to the outer circumference. An axial through hole 242 with a rectangular cross section that communicates with the radial through hole 241 and extends in the axial direction is formed on the outer peripheral side of the annular recess 24a and between the cylindrical portion 22 and the permanent magnet 25. Ru. A plurality of radial through holes 241 and axial through holes 242 are formed in the circumferential direction of the rotor 20 . An opening 243 having a circular cross section is formed in the end plate 201b on the other end 20b side of the axial through hole 242 at a position corresponding to the axial through hole 242.

The refrigerant introduced from the refrigerant introduction hole 14 flows inward from the one end 20a side of the annular recess 24a. The refrigerant moves toward the inner peripheral surface of the annular recess 24a due to centrifugal force caused by the rotation of the rotor 20. The refrigerant flows into the radial through hole 241 and from the radial through hole 241 into the axial through hole 242 due to centrifugal force. The refrigerant further moves through the axial through hole 242 from the one end 20a side to the other end 20b side. The refrigerant that has reached the other end 20b side of the axial through hole 242 flows out of the rotor 20 through the opening 243. This refrigerant is scattered toward the second coil end 152 of the stator 15 due to the centrifugal force caused by the rotor 20 rotations.

Of the refrigerant introduced into the annular recess 24a, the refrigerant that has not passed through the radial through hole 241 flows out from the opening of the annular recess 24a. This refrigerant moves radially outward through the gap between the rotor 20 and the pedestal 12a of the housing 10 due to the centrifugal force caused by the rotation of the rotor 20, and scatters toward the first coil end 151 of the stator 15.

With this configuration, the rotor 20 is cooled by the refrigerant introduced from the outside of the motor 1 into the housing 10 and passing through the axial through hole 242 formed in the rotor 20. Further, the refrigerant cools the first coil end 151 and the second coil end 152 of the stator 15 by scattering them. The refrigerant then flows down into a refrigerant reservoir 18 (see FIG. 7) formed at the bottom of the housing 10. This refrigerant is again introduced into the housing 10 through the refrigerant introduction hole 14.

Next, the configuration of the rotor 20 will be explained in more detail.

FIG. 2 is a perspective view of the rotating shaft 21 and the cylindrical portion 22 that constitute the rotor 20 of this embodiment. FIG. 3 is a perspective view of the rotor 20 with the permanent magnets 25 attached thereto. FIG. 4 is a perspective view of the rotor 20 with the end plate 201 attached. FIG. 5 is a radial cross-sectional view of the rotor 20.

As shown in FIG. 2, a plurality of grooves 225 are formed in the outer peripheral surface of the cylindrical portion 22 in the axial direction. A radial through hole 241 that radially penetrates the inner peripheral side of the cylindrical portion 22, that is, the annular recess 24a and the groove 225, is provided on one end 20a side of each groove 225 (on the near side in FIG. 2). It is formed.

The groove portion 225 is formed by a set of upright walls 221 that stand up from the outer periphery of the cylindrical portion 22 . The upright wall 221 is a wall-shaped portion that extends linearly in the axial direction, and a plurality of upright walls 221 are arranged at predetermined intervals in the circumferential direction of the cylindrical portion 22. Note that on the outer periphery of the cylindrical portion 22, standing walls 221a having a high standing height and standing walls 221b having a lower standing height than the standing walls 221a are alternately arranged.

The groove portion 225 has a permanent magnet 25 disposed on its outer periphery, so that the inner circumferential surface of the permanent magnet 25 and the upper surface of the standing wall 221 are in contact with each other, and a shaft surrounded by the permanent magnet 25 and the set of standing walls 221 is formed. A directional space is formed (see Figure 3). This space is configured as an axial through hole 242 through which the refrigerant flows in the axial direction of the rotor 20. Note that, as shown in FIG. 3, a cylindrical holding member 202 that holds the permanent magnet 25 is fitted around the outer periphery of the permanent magnet 25.

As shown in FIG. 4, annular end plates 201a and 201b are arranged at one end 20a and the other end 20b of the rotor 20, respectively, to fix the permanent magnet 25 in the axial direction, and to fix the permanent magnet 25 in the axial direction. The axial through hole 242 is closed at the end 20a and the other end 20b.

As shown in FIG. 5, the permanent magnets 25 of the rotor 20 are composed of a plurality of fan-shaped segment magnets 251 arranged in an annular manner. The segment magnets 251 are composed of segment magnets 251a in contact with a set of upright walls 221a and segment magnets 251b in contact with a set of upright walls 221b, and the segment magnets 251a and the segment magnets 251b are arranged alternately. These segment magnets 251 are arranged so that the magnetic pole directions of adjacent segment magnets 251 differ by 90 degrees.

The segment magnet 251a has a flat inner peripheral surface, and an axial through hole 242 is formed by contacting the upper surface of the set of upright walls 221a.

The segment magnet 251b is formed such that its inner circumferential surface is closer to the cylindrical portion 22 than the segment magnet 251a, and has a recess 255b recessed radially outward. When the segment magnet 251b contacts the upper surface of the set of upright walls 221b, an axial through hole 242 is formed by the recess 255b of the segment magnet 251b and the set of upright walls 221b.

With such a configuration, the axial through hole 242 is formed between the cylindrical portion 22 and the permanent magnet 25, so that the refrigerant flowing through the axial through hole 242 comes into direct contact with the permanent magnet 25. Heat exchange can be performed between the Thereby, the cooling efficiency of the permanent magnets 25 of the rotor 20 by the refrigerant can be improved. By improving the cooling efficiency of the permanent magnet 25, demagnetization of the permanent magnet 25 due to heat can be suppressed, and the efficiency of the motor 1 can be improved.

Note that by alternately arranging segment magnets 251a and segment magnets 251b having different shapes in contact with the cylindrical portion 22, the permanent magnet 25 configured in an annular shape is prevented from rotating relative to the cylindrical portion 22. Ru.

Next, the structure of the annular recess 24a will be explained.

FIG. 6 is an axial cross-sectional view of the rotor 20 centered on the annular recess 24a.

The annular recess 24a is a space formed by the outer circumferential surface of the rotating shaft 21, the inner circumferential surface of the cylindrical portion 22, and the connecting portion 23. The annular recess 24a has a small diameter part 245 with a small cross-sectional area on the opening side, and an enlarged diameter part 246 with a larger radial cross-sectional area, that is, expanded in the radial direction, on the connection part 23 side than the small diameter part 245. . Between the small diameter portion 245 and the enlarged diameter portion 246, there is a stepped portion 247 in which the cross-sectional area of the annular recess 24a increases in diameter in a step or taper shape. A radial through hole 241 is formed in the stepped portion 247 .

Since the annular recess 24a has such a shape, the refrigerant introduced into the annular recess 24a from the refrigerant introduction hole 14 of the base 12a moves radially outward of the annular recess 24a due to the centrifugal force caused by the rotation of the rotor 20. , is stored on the inner periphery of the enlarged diameter portion 246. The refrigerant stored in the enlarged diameter portion 246 flows into the radial through hole 241 formed in the stepped portion 247 and is pushed into the axial through hole 242 due to centrifugal force. Thereby, the refrigerant flows through the axial through hole 242 inside the rotor 20 from the one end 20a side to the other end 20b side, cooling the inside of the rotor 20, especially the permanent magnets 25.

The end plate 201b of the other end 20b of the stator 15 has a plurality of openings 243 (see FIG. 1) formed at positions corresponding to the respective axial through holes 242. The opening 243 is formed so that its opening cross-sectional area is greater than or equal to the opening cross-sectional area of the axial through hole 242. Further, the opening 243 is formed such that a radially outer portion of the opening 243 is located on the radial side of the axial through hole 242 .

By forming the opening 243 in this way, the refrigerant that flows through the axial through hole 242 and reaches the other end 20b is caused by the centrifugal force caused by the rotation of the rotor 20 to move from the opening 243 to the diameter of the rotor 20. It quickly flows outward. This refrigerant scatters toward the second coil end 152 of the stator 15 located radially outward than the other end 20b of the rotor 20, and cools the second coil end 152.

The pedestal 12b near the other end 20b of the rotor 20 has a small diameter portion 121b that enters the annular recess 24b, and a pedestal 12b that is erected radially outward from the small diameter portion 121b (enlarged in diameter) and attached to the end plate 201b of the rotor 20. and flange portions 122b configured to face each other. The portion from the small diameter portion 121b to the flange portion 122 is formed to gradually move away from the rotor 20 as it goes radially outward. By configuring the pedestal 12b in this way, the refrigerant flowing out from the opening 243 moves radially outward while colliding with the small diameter portion 121b and the flange portion 16b, and reaches the second coil end 152 of the stator 15. Moving.

Similarly, the pedestal 12a near one end 20a of the rotor 20 has a small diameter portion 121a that enters into the annular recess 24a, and an end plate 201a of the rotor 20 that is erected (diameter expanded) on the outside in the radial direction from the small diameter portion 121a. The flange portion 122a is configured to face the flange portion 122a. The portion from the small diameter portion 121a to the flange portion 122a is formed to gradually move away from the rotor 20 as it goes radially outward. By configuring the pedestal 12 in this way, the refrigerant that has moved into the gap between the one end 20a of the rotor 20 and the pedestal 12a moves radially outward while colliding with the small diameter portion 121a and the flange portion 16a. , and moves to the first coil end 151 of the stator 15.

Next, a configuration for circulating the refrigerant of the motor 1 of this embodiment will be described.

FIG. 7 is an explanatory diagram of the motor 1 of this embodiment, and shows a configuration including a pump 40 that circulates refrigerant.

In the motor 1, the refrigerant introduced into the housing 10 from the refrigerant introduction hole 14 flows through the annular recess 24a of the rotor 20, the first coil end 151 of the stator 15, the rotor 20, and the second coil end 152 of the stator 15. Cooling. The refrigerant then flows down inside the housing 10 and is stored in the refrigerant storage section 18 at the bottom of the housing 10.

A pipe 30 and a pump 40 are connected to the refrigerant storage section 18 . The pipe 30 is connected to the refrigerant introduction hole 14 of the pedestal 12. The pump 40 may be an electric pump driven by electric power, or a mechanical pump driven by the rotation of the rotating shaft 21 of the motor 1 being transmitted by a gear or the like.

The pump 40 pumps up the refrigerant stored in the refrigerant storage section 18 and discharges the refrigerant into the refrigerant introduction hole 14 via the piping 30.

With this configuration, the pump 40 can be used to circulate the refrigerant for cooling the motor 1.

FIG. 8 is an explanatory diagram of another example of the motor 1 of this embodiment, and shows a configuration in which the motor 1 is equipped with a transmission 60.

The transmission 60 is connected to the rotating shaft 21 of the motor 1, changes the speed (decelerates or speeds up) the rotation of the motor 1 using a plurality of gears 61, and outputs the rotation.

The transmission 60 has a refrigerant storage section 65 at its lower part. The refrigerant storage section 65 communicates with the refrigerant storage section 18 of the motor 1, and the refrigerant stored in the refrigerant storage section 18 is also stored in the refrigerant storage section 65. A part of the gear 61 is immersed in the refrigerant reservoir 65 .

As the motor 1 rotates, the gear 61 of the transmission 60 rotates, and the refrigerant stored in the refrigerant storage section 65 is scraped upward. The refrigerant scraped up by the gear 61 of the transmission 60 flows into the refrigerant introduction hole 14 of the base 12.

With such a configuration, the refrigerant for cooling the motor 1 can be circulated using the rotation of the gear 61 of the transmission 60.

As explained above, in the embodiment of the present invention, the motor 1 (rotating electric machine) includes the rotor 20, the stator 15 provided on the outer periphery of the rotor 20, and the housing 10 that accommodates the rotor 20 and the stator 15. . The rotor 20 includes a rotating shaft 21 , a cylindrical cylindrical portion 22 that houses a permanent magnet 25 , and a connecting portion 23 that connects the outer circumferential surface of the rotating shaft 21 and the inner circumferential surface of the cylindrical portion 22 . . The rotor 20 is a space formed by the rotating shaft 21, the cylindrical portion 22, and the connecting portion 23, and includes an annular recess 24a that opens in the axial direction across the connecting portion 23. The housing 10 includes a pedestal 12 that rotatably supports a rotating shaft 21. A refrigerant introduction hole 14 is provided around the pedestal 12 to introduce a refrigerant toward the annular recess 24a. The rotor 20 includes a radial through hole 241 that radially penetrates the cylindrical portion 22 in the annular recess 24a, and an axial through hole 242 that communicates with the radial through hole 241 and axially penetrates the inside of the rotor 20. The permanent magnet 25 is cooled by the refrigerant introduced into the annular recess 24a passing through the radial through hole 241 and the axial through hole 242.

With such a configuration, the axial through hole 242 is formed between the cylindrical portion 22 and the permanent magnet 25, so that the refrigerant introduced from the refrigerant introduction hole 14 into the annular recess 24a is centrifuged by the rotation of the rotor 20. Since the force flows through the radial through hole 241 and the axial through hole 242 and cools the permanent magnet 25, the cooling efficiency of the permanent magnet 25 of the rotor 20 by the refrigerant can be improved. By improving the cooling efficiency of the permanent magnet 25, demagnetization of the permanent magnet 25 due to heat can be suppressed, and the efficiency of the motor 1 can be improved.

Furthermore, in this embodiment, the inner circumferential surface of the cylindrical portion 22 has an enlarged diameter portion 246 whose inner diameter is larger on the connecting portion side via the stepped portion 247 than on the opening side of the annular recess 24a; The radial through hole 241 is formed in the stepped portion 247 .

With such a configuration, the refrigerant introduced into the annular recess 24a can be stored in the enlarged diameter portion 246 having a large inner diameter due to centrifugal force, and the refrigerant can be guided to the radial through hole 241 more reliably.

Further, in this embodiment, there is a gap between the pedestal 12 and the rotor 20, and a part of the refrigerant introduced from the coolant introduction hole 14 flows to the stator 15 via the gap, so that the inside of the housing is The refrigerant introduced can be used not only for cooling the rotor 20 but also for cooling the stator 15 and the first coil end 151.

Furthermore, in this embodiment, the other end 20b of the permanent magnet 25 is provided with an end plate 201b, and the end plate 201b has an opening 243 through which the axial through hole 242 opens into the housing 10. The opening cross-sectional area of the opening 243 is greater than or equal to the opening cross-sectional area of the axial through-hole 242, and at least a portion of the opening 243 is located on the outer side of the axial through-hole 242 in the radial direction.

With such a configuration, the refrigerant flowing through the axial through hole 242 can quickly flow out into the housing 10, and the refrigerant can be easily introduced to the radially outer side of the rotor 20, that is, to the stator 15 side.

Furthermore, in this embodiment, the pedestal 12 has a small diameter portion 121b that fits into the inner periphery of the annular recess 24b, and a flange portion 122b that stands radially outward from the small diameter portion 121b on the axial end side.

With this configuration, the refrigerant flowing out from the opening 243 moves radially outward from the small diameter portion 121b of the pedestal 12 while colliding with the flange portion 122b due to the centrifugal force caused by the rotation of the rotor 20, and then moves to the stator 15. can be done.

Moreover, in this embodiment, the permanent magnet 25 is arranged around the cylindrical part 22, and the axial through hole 242 is formed between the outer periphery of the cylindrical part 22 and the inner periphery of the permanent magnet 25, and the permanent magnet 25 has a plurality of magnetic poles in the circumferential direction, and the magnetic poles are arranged in a Halbach arrangement. Therefore, in the motor 1 to which the Halbach arrangement is applied, by flowing the refrigerant so as to be in contact with the permanent magnet 25, the permanent magnet 25 can be properly aligned. can be cooled to

Although the embodiments of the present invention have been described above, the above embodiments merely show a part of the application examples of the present invention, and are not intended to limit the technical scope of the present invention to the specific configurations of the above embodiments. .

Although the permanent magnet 25 of this embodiment has a configuration in which a plurality of segment magnets 251 are arranged in a Halbach array, the present invention is not limited to this. Permanent magnets with other magnetic pole arrangements may be used as long as the axial through hole can be arranged between the inner periphery of the permanent magnet in which annular or segment magnets are arranged in an annular manner and the cylindrical portion 22.

1: Motor, 10: Housing, 12: Pedestal, 14: Refrigerant introduction hole, 15: Stator, 16: Flange portion, 20: Rotor, 20a: One end, 20b: Other end, 21: Rotating shaft, 22: Cylindrical part, 23: Connection part, 24a: Annular recess, 25: Permanent magnet, 40: Pump, 60: Transmission, 151: First coil end, 152: Second coil end, 201a: End plate , 201b: End plate, 241: Radial through hole, 242: Axial through hole, 243: Opening, 245: Small diameter portion, 246: Expanded diameter portion, 247: Step portion

Claims (6)

A rotating electrical machine comprising a rotor, a stator provided on the outer periphery of the rotor, and a housing housing the rotor and the stator,
The rotor includes a rotating shaft, a cylindrical cylindrical portion including a permanent magnet, and a connecting portion connecting an outer circumferential surface of the rotating shaft and an inner circumferential surface of the cylindrical portion,
The rotor is a space formed by the rotating shaft, the cylindrical portion, and the connecting portion, and includes an annular recess that opens in the axial direction across the connecting portion,
The housing includes a pedestal that rotatably supports the rotating shaft,
The pedestal is provided with a refrigerant introduction hole for introducing refrigerant toward the annular recess,
The rotor includes a radial through hole that radially penetrates the cylindrical portion in the annular recess, and an axial through hole that communicates with the radial through hole and axially penetrates the inside of the rotor. have,
Coolant introduced into the annular recess cools the permanent magnet by passing through the radial through hole and the axial through hole.
Rotating electric machine. The rotating electric machine according to claim 1,
The inner circumferential surface of the cylindrical part has an enlarged diameter part whose inner diameter is larger on the connecting part side via a step part than the inner diameter on the opening side of the annular recess,
The radial through hole is formed in the step part of the enlarged diameter part,
Rotating electric machine. The rotating electric machine according to claim 1,
There is a gap between the pedestal and the rotor,
A part of the refrigerant introduced from the refrigerant introduction hole flows to the stator via the gap,
Rotating electric machine. The rotating electric machine according to claim 1,
An end plate is provided at an axial end of the permanent magnet, and the end plate has an opening through which the axial through hole opens into the housing;
The opening cross-sectional area of the opening is greater than or equal to the opening cross-sectional area of the axial through-hole, and at least a portion of the opening is located radially outward than the axial through-hole.
Rotating electric machine. The rotating electric machine according to claim 1,
The pedestal has a small diameter portion that enters the inner periphery of the annular recess near the end of the rotor, and a flange portion that stands radially outward from the small diameter portion on the axial end side.
Rotating electric machine. The rotating electric machine according to claim 1,
The permanent magnet is arranged around the cylindrical part, and the axial through hole is formed between the cylindrical part and the permanent magnet,
The permanent magnet has a plurality of magnetic poles in the circumferential direction, and the magnetic poles are arranged in a Halbach array.
Rotating electric machine.

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