CN110601446A

CN110601446A - Rotor and rotating electrical machine

Info

Publication number: CN110601446A
Application number: CN201910488844.8A
Authority: CN
Inventors: 竹岛彻
Original assignee: Honda Motor Co Ltd
Current assignee: Honda Motor Co Ltd
Priority date: 2018-06-13
Filing date: 2019-06-05
Publication date: 2019-12-20
Anticipated expiration: 2039-06-05
Also published as: JP2019216555A; CN110601446B; JP7115912B2

Abstract

Provided are a rotor and a rotating electric machine, which can improve cooling efficiency. The rotor is provided with: an output shaft (5) that is configured to be rotatable about an axis (C) and that has a shaft core cooling passage (15) through which a cooling medium flows; and a rotor core (4) that is fixed to the output shaft (5) and that has a rotor internal flow path (12), wherein an upstream end of the rotor internal flow path (12) communicates with the shaft core cooling path (15), and a downstream end of the rotor internal flow path (12) opens at an end surface (48, 49) of the rotor core facing in a direction in which the axis extends, and wherein the rotor internal flow path (12) has, at least in part, an inclined portion (26, 27) that extends radially outward in a process from the upstream end toward the downstream end.

Description

Rotor and rotating electrical machine

Technical Field

The present invention relates to a rotor and a rotating electric machine.

Background

Conventionally, a rotating electrical machine has been used as a power source for hybrid vehicles and electric vehicles. In a rotating electrical machine, magnetic attraction and repulsion are generated between a magnet provided in a rotor core and a stator around which a coil is wound. Thereby, the rotor rotates relative to the stator.

The rotor generates heat due to the influence of eddy current generated in the magnet during rotation. When the magnetic force is reduced due to heat generation of the magnet (so-called thermal demagnetization), the performance of the rotating electrical machine may be reduced.

Thus, for example, japanese patent application laid-open No. 2009-284603 discloses a structure in which a cooling medium is circulated through weight-reduced holes that axially penetrate a rotor core. According to this structure, it is considered that the cooling medium can cool the rotor during the passage through the lightening holes.

Problems to be solved by the invention

However, in the technique of the above-mentioned document, there is room for improvement in that the coolant is smoothly passed through the lightening holes. That is, in the technique of the above-described document, the coolant that is biased toward the outer peripheral side of the lightening hole due to the rotation of the rotor is likely to be accumulated in the lightening hole. When the cooling medium accumulated in the lightening holes becomes high temperature by heat exchange with the rotor, the cooling efficiency of the rotor is lowered.

Disclosure of Invention

An object of an aspect of the present invention is to provide a rotor and a rotating electrical machine that can improve cooling efficiency.

Means for solving the problems

A rotor according to an aspect of the present invention (for example, the rotor 7 according to the first embodiment) includes: an output shaft (e.g., the output shaft 5 in the first embodiment) configured to be rotatable about an axis (e.g., the axis C in the first embodiment) and having a shaft core cooling passage (e.g., the shaft core cooling passage 15 in the first embodiment) through which a cooling medium flows; and a rotor core (for example, the rotor core 4 in the first embodiment) that is fixed to the output shaft and that has a rotor internal flow path (for example, the rotor internal flow path 12 in the first embodiment) whose upstream end portion communicates with the shaft core cooling path and whose downstream end portion is open at an end surface (for example, a first side core end surface 48 and a second side core end surface 49 in the first embodiment) of the rotor core facing in the axial direction, and that has, at least in part, inclined portions (for example, the first inclined portion 26 and the second inclined portion 27 in the first embodiment) extending outward in the radial direction in a process from the upstream end portion toward the downstream end portion.

In one example of the above aspect, the rotor internal flow path includes: a connection path (for example, the core connection path 45 and the sleeve connection path 28 in the first embodiment) that communicates with the shaft core cooling path; a first cooling medium conveyance path (for example, a first cooling medium conveyance path 22 in the first embodiment) extending from the connection path toward a first side in the axial direction, a downstream end of the first cooling medium conveyance path being open at an end surface of the rotor core on the first side; and a second cooling medium supply passage (for example, a second cooling medium supply passage 23 in the first embodiment) extending from the connection passage toward a second side in the axial direction, a downstream end of the second cooling medium supply passage being open at an end surface of the second side of the rotor core, the connection passage being provided in a central portion in the axial direction, and the first cooling medium supply passage and the second cooling medium supply passage each having the inclined portion at least in part.

In one example of the above aspect, the inclined portion is provided in the first cooling medium conveyance path and the second cooling medium conveyance path over the entire axial direction.

In one example of the above configuration, a sleeve (for example, the sleeve 2 in the first embodiment) having the rotor internal flow path formed therein is attached to the rotor core in a separate manner.

In one example of the above aspect, the sleeve is a resin product.

In one example of the above configuration, a plurality of communication holes (for example, the communication hole 47 in the first embodiment) are formed in the rotor core in the circumferential direction, and the sleeves are disposed in the plurality of communication holes.

In one example of the above aspect, the communication hole and the sleeve are formed in a polygonal shape in a plan view viewed from the axial direction.

In one example of the above aspect, the communication hole and the sleeve are formed in an arc shape centered on the axis in a plan view seen from the axial direction.

In one example of the above configuration, a magnet (for example, the magnet 6 in the first embodiment) is disposed along the axial direction at a position in the rotor core where at least a part overlaps with the rotor internal flow path in a side view from the radial direction.

A rotating electrical machine according to another aspect of the present invention (for example, the rotating electrical machine 1 according to the first embodiment) includes the rotor according to the above aspect; and a stator (e.g., the stator 3 in the first embodiment) surrounding the rotor.

In one example of the above aspect, the stator includes: a stator core (e.g., the stator core 30 in the first embodiment); and a coil (e.g., coil 32 in the first embodiment) that is attached to the stator core and has coil end portions (e.g., coil end portions 34 and 35 in the first embodiment) that protrude from both end surfaces in the axial direction in the stator core, the coil end portions being located outside in the axial direction with respect to an end surface on a first side in the axial direction and an end surface on a second side in the axial direction in the rotor core.

Effects of the invention

According to the rotor of the aspect of the invention, the rotor internal flow path has, at least in part, the inclined portion extending outward in the radial direction in a process from the upstream side end portion toward the downstream side end portion. Therefore, the cooling medium supplied from the core cooling passage to the rotor internal passage is transferred to the wall surface of the inclined portion by the centrifugal force generated by the rotation of the rotor, and moves from the upstream end portion toward the downstream end portion. Thereafter, the cooling medium is discharged from the end surface facing the axial direction in the rotor core. Thus, the cooling medium stably flows through the rotor internal flow passage without being accumulated in the rotor internal flow passage, so that the cooling medium at a low temperature is easily supplied to the rotor, and the rotor can be efficiently cooled. Therefore, a rotor capable of improving cooling efficiency can be provided.

In the example of the above-described configuration, the connection path is provided in the center portion in the axial direction in the rotor core, and the rotor internal flow path has the first cooling medium conveyance path that opens to the end surface on the first side of the rotor core and the second cooling medium conveyance path that opens to the end surface on the second side of the rotor core, so that the cooling medium is easily distributed and supplied to the first cooling medium conveyance path 22 and the second cooling medium conveyance path 23 equally. This can suppress the occurrence of a temperature difference due to imbalance in the cooling effect between the first side and the second side of the rotor 7. Further, since the rotor 7 can have a symmetrical structure with respect to the axial center portion of the rotor core 4, the weight balance of the rotor 7 can be made uniform on the first side and the second side in the axial direction. As a result, the shaft of the rotor 7 is prevented from wobbling, and the rotor 7 can be rotated stably. Further, the center of gravity can be prevented from being biased by the flow of the cooling medium in the rotor internal flow passage 12. Therefore, a stable and high-performance rotor can be realized in which the cooling efficiency can be improved and the bias of the rotor can be suppressed.

In the above-described aspect, since the inclined portions are provided in the first cooling medium conveyance path and the second cooling medium conveyance path in the entire axial direction, a force toward the downstream end portion is constantly applied to the cooling medium flowing into the first cooling medium conveyance path and the second cooling medium conveyance path by a centrifugal force. Thus, the cooling medium flows stably, is transferred to the wall surface of the inclined portion, moves from the upstream end portion toward the downstream end portion, and is discharged from the end surface of the rotor core without being accumulated in the rotor core. Thus, the rotor can be efficiently cooled. Therefore, a rotor capable of improving cooling efficiency can be provided.

In the above-described aspect, since the rotor internal flow path is formed in the sleeve that is separate from the rotor core, the rotor internal flow path can be processed more easily than when the rotor internal flow path is formed directly in the rotor core. Therefore, a rotor that can be easily processed can be provided.

In the above-described example, since the sleeve is made of a resin, the surface of the rotor internal flow path can be made smooth as compared with a case where the rotor internal flow path is formed in a metallic sleeve by laminating electromagnetic steel plates, for example. This makes it possible to facilitate the flow of the cooling medium. In addition, the processing of the flow path inside the rotor can be facilitated. Further, by selecting a resin having a high heat transfer coefficient as the resin used for the sleeve, the cooling medium flowing through the rotor internal flow path formed in the sleeve can cool the rotor core through the resin. Therefore, the rotor can be easily processed and has high cooling efficiency.

In the above-described aspect, since the sleeve is disposed in the plurality of communication holes provided in the circumferential direction of the rotor core, the sleeve can facilitate the processing of the flow path inside the rotor, and the sleeve only needs to form the communication holes having the same shape in the axial direction in the rotor core, thereby facilitating the processing of the rotor core. Further, since the plurality of rotor internal flow paths can be arranged along the circumferential direction easily, the cooling efficiency of the rotor can be improved. Therefore, the rotor which improves the cooling efficiency and is easy to process can be provided.

In the above aspect, the communication hole and the sleeve are formed in a polygonal shape in a plan view as viewed from the axial direction, and therefore, when the sleeve is inserted into the communication hole, the sleeve can be easily positioned by inserting the sleeve so that a corner of the communication hole corresponds to a corner of the sleeve. Therefore, the rotor having improved mounting and workability can be formed.

In the above aspect, the communicating hole and the sleeve are formed in an arc shape centering on the axis line in a plan view from the axial direction, and therefore, when the sleeve is inserted into the communicating hole, the orientation of the sleeve is uniquely determined. This can prevent erroneous assembly of the sleeve. Therefore, the rotor having improved mounting and workability can be formed.

In one example of the above configuration, the magnet is disposed along the axial direction at a position at least partially overlapping the rotor internal flow path in a side view in the radial direction. Therefore, heat generated by the magnets is easily transferred to the rotor core and absorbed by the cooling medium flowing through the internal flow path. Thereby, the cooling medium can effectively cool the magnet. Therefore, a rotor capable of improving cooling efficiency can be provided.

According to the rotating electrical machine according to another aspect of the present invention, a rotating electrical machine having high cooling performance can be provided that includes a rotor capable of improving cooling efficiency as compared with the conventional art.

In the above aspect, the cooling medium flowing through the inclined portion of the first cooling medium conveyance path is subjected to a force toward the first side in the axial direction by a component force of the centrifugal force. Thereby, the cooling medium discharged from the first cooling medium conveyance path is accelerated toward the first side in the axial direction. Therefore, the cooling medium discharged from the first cooling medium conveyance path is scattered outward in the axial direction from the end surface located on the first side of the rotor core. The cooling medium discharged from the first cooling medium conveyance path is guided radially outward by centrifugal force and is scattered, and is supplied to the coil end portion located on the first side in the axial direction with respect to the stator core. Similarly, a force toward the second side in the axial direction acts on the cooling medium flowing through the inclined portion of the second cooling medium conveyance path due to a reaction force of the centrifugal force. Thereby, the cooling medium discharged from the second cooling medium conveyance path is accelerated toward the second side in the axial direction. Therefore, the cooling medium discharged from the second cooling medium conveyance path is scattered outward in the axial direction from the end surface located on the second side of the rotor core. The cooling medium discharged from the second cooling medium conveyance path is guided radially outward by centrifugal force, is scattered, and is supplied to the coil end portion located on the second side in the axial direction with respect to the stator core.

Here, since the coil end portions are located outside the rotor core in the axial direction with respect to the end surface on the first side in the axial direction and the end surface on the second side in the axial direction, the cooling medium discharged from the end surface of the rotor core is scattered outward in the axial direction from the end surface of the rotor and is supplied to the coil end portions. This enables the cooling medium to be directly sprayed to the coil having a large heat generation amount, thereby efficiently cooling the coil. Further, since the cooling medium is supplied from the end face of the rotor in the direction away from the axial direction, the cooling medium can be prevented from entering the gap between the stator and the rotor.

In addition, when the end face plate is provided on the end face of the rotor, it is not necessary to provide a guide portion for guiding the cooling medium from the end face of the rotor toward the outside in the axial direction on the end face plate, and therefore the rotor can be made to have a simple structure.

Therefore, according to the aspect of the present invention, it is possible to provide a rotating electric machine that improves cooling efficiency and is easy to machine. In addition, a high-performance rotating electrical machine in which the cooling medium does not easily enter the gap between the stator and the rotor can be formed.

Drawings

Fig. 1 is a sectional view showing a schematic configuration of a rotating electric machine according to a first embodiment.

Fig. 2 is a partial sectional view of a rotating electric machine showing a rotor cooling structure according to a first embodiment.

Fig. 3 is a cross-sectional view of the rotor core according to the first embodiment taken along line III-III of fig. 2.

Fig. 4 is a perspective view of the sleeve of the first embodiment.

Fig. 5 is a sectional view of the sleeve of the first embodiment.

Fig. 6 is a side view of a rotor core according to a second embodiment.

Fig. 7 is a perspective view of a sleeve of the second embodiment.

Fig. 8 is a sectional view of the sleeve of the second embodiment.

Fig. 9 is a perspective view of a sleeve according to a first modification of the second embodiment.

Fig. 10 is a side view of a rotor core of a third embodiment.

Fig. 11 is a perspective view of a sleeve of the third embodiment.

Fig. 12 is a sectional view of a sleeve of the third embodiment.

Fig. 13 is a perspective view of a sleeve according to a first modification of the third embodiment.

Fig. 14 is a side view of a rotor core according to a fourth embodiment.

Fig. 15 is a perspective view of a sleeve of the fourth embodiment.

Fig. 16 is a sectional view of a sleeve of the fourth embodiment.

Fig. 17 is a partial cross-sectional view of a rotary electric machine showing a rotor cooling structure according to a fifth embodiment.

Fig. 18 is a partial cross-sectional view of a rotary electric machine showing a rotor cooling structure according to a first modification of the fifth embodiment.

Description of reference numerals:

1 rotating electrical machine

2 sleeve

3 stator

4-rotor iron core

5 output shaft

6 magnet

7 rotor

12 rotor internal flow path

15 axle core cooling circuit

22 first cooling medium transport path (cooling medium transport path)

23 second cooling medium transport path (cooling medium transport path)

26 first inclined part (inclined part)

27 second inclined part (inclined part)

28 sleeve connecting road (connecting road)

30 stator core

32 coil

34 coil end part

35 coil end part

45 iron core connecting road (connecting road)

47 communication hole

48 first side core end face

49 second side core end face

The C axis.

Detailed Description

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

(first embodiment)

(rotating electric machine)

Fig. 1 is a sectional view showing a schematic structure of a rotating electric machine according to an embodiment.

The rotating electric machine 1 shown in fig. 1 is a running motor mounted on a vehicle such as a hybrid vehicle or an electric vehicle, for example. However, the configuration of the present invention is not limited to the motor for running, and can be applied to a motor for power generation, a motor for other applications, and a rotating electrical machine (including a generator) other than a vehicle.

The rotating electric machine 1 includes a housing 11, a stator 3, and a rotor 7.

The housing 11 accommodates the stator 3 and the rotor 7. A cooling medium (not shown) is accommodated in the casing 11. The stator 3 is disposed in the casing 11 in a state in which a part thereof is immersed in the cooling medium. As the cooling medium, atf (automatic transmission fluid), which is a working oil used for lubrication of the transmission, power transmission, and the like, is preferably used.

In the following description, a direction along the axis C of the output shaft 5 of the rotor 7 is simply referred to as an axial direction, a direction perpendicular to the axis C is referred to as a radial direction, and a direction around the axis C is referred to as a circumferential direction.

(stator)

The stator 3 includes a stator core 30 and a coil 32 attached to the stator core 30. The stator core 30 is cylindrical and disposed coaxially with the axis C. The stator core 30 is fixed to an inner peripheral surface of the housing 11. Stator core 30 is formed by laminating electromagnetic steel sheets in the axial direction. The stator core 30 may be a so-called dust core.

The coil 32 is fitted to the stator core 30. The coil 32 includes a U-phase coil, a V-phase coil, and a W-phase coil arranged with a predetermined phase difference in the circumferential direction. The coil 32 includes an insertion portion 33 that passes through a slot (not shown) of the stator core 30, a coil end portion 34 that protrudes from the stator core 30 to a first side in the axial direction, and a coil end portion 35 that protrudes from the stator core 30 to a second side in the axial direction. In the stator core 30, a current flows through the coil 32 to generate a magnetic field.

(rotor)

Fig. 2 is a partial sectional view of the rotating electric machine showing a rotor cooling structure. Fig. 3 is a cross-sectional view of the rotor core taken along line III-III of fig. 2.

As shown in fig. 2 and 3, the rotor 7 is configured to be rotatable about an axis C. The rotor 7 includes a rotor core 4, an output shaft 5, a magnet 6, and a sleeve 2.

(output shaft)

As shown in fig. 2, the output shaft 5 is rotatably supported by the housing 11.

The output shaft 5 has a core cooling passage 15 and a radial flow passage 14.

The core cooling passage 15 extends in the axial direction at a position coaxial with the axis C inside the output shaft 5. The cooling medium pumped from the cooling medium pump flows through the shaft core cooling passage 15 in the axial direction. The coolant pump may be a so-called motor pump that is driven in conjunction with the rotation of the output shaft 5, or may be an electric pump that is driven independently of the rotation of the output shaft 5.

The radial flow passage 14 extends in the radial direction at the axial center portion in the interior of the output shaft 5.

The radial inner end of the radial flow passage 14 communicates with the inside of the shaft core cooling passage 15.

The cooling medium flowing through the shaft core cooling passage 15 can flow into the radial flow passage 14.

The radial outer end of the radial flow passage 14 opens on the outer peripheral surface of the output shaft 5.

In addition, a plurality of radial flow passages 14 (8 in the present embodiment) are formed in the circumferential direction. The radial flow passage 14 may be disposed offset to the first side or the second side with respect to the axial center portion.

(rotor core)

The rotor core 4 is disposed at a radially inner side with a space with respect to the stator 3.

The rotor core 4 is formed in a cylindrical shape disposed coaxially with the axis C. A shaft through hole 41 for axially penetrating the rotor core 4 is formed in a radial center portion of the rotor core 4.

The output shaft 5 is fixed to the shaft through hole 41 by press fitting or the like, for example. Therefore, the rotor core 4 is configured to be rotatable integrally with the output shaft 5 about the axis C.

A magnet holding hole 46 is formed in the outer peripheral portion of the rotor core 4 to axially penetrate the rotor core 4. The magnet holding holes 46 are formed in plurality at intervals in the circumferential direction. Magnets 6 are inserted into the magnet holding holes 46.

The magnet 6 is, for example, a rare-earth magnet. Examples of the rare-earth magnet include neodymium magnet, samarium-cobalt magnet, and praseodymium magnet.

As shown in fig. 3, the rotor core 4 includes a communication hole 47 and a core connection path (connection path) 45 between the magnet holding hole 46 and the shaft through hole 41 in the radial direction.

The communication hole 47 axially penetrates the rotor core 4. The communication holes 47 have a circular cross section and have the same inner diameter. A plurality of (8 in the present embodiment) communication holes 47 are formed in the circumferential direction.

The core connection path 45 is provided at the center of the rotor core 4 in the axial direction, and extends in the radial direction between the communication hole 47 and the shaft through hole 41. The radially inner end of the core connecting passage 45 opens on the inner circumferential surface of the shaft through hole 41. The radially inner end of the core connecting passage 45 communicates with the radially outer end of the radial flow passage 14. Thereby, the cooling medium flowing through the radial flow channels 14 can flow into the core connecting channel 45.

The outer end of the core connecting passage 45 in the radial direction communicates with the inside of the communication hole 47. The core connecting path 45 may be disposed offset to the first side or the second side in the axial direction with respect to the center portion in the axial direction.

(Sleeve)

Fig. 4 is an external perspective view of the sleeve, and fig. 5 is a sectional view of the sleeve.

As shown in fig. 4 and 5, the sleeve 2 is a columnar member, and is preferably made of a resin having high thermal conductivity, for example. The sleeve 2 is inserted into the communication hole 47 of the rotor core 4. The sleeve 2 may be fixed to the communication hole 47 of the rotor core 4 by bonding or the like, or may be fixed to the communication hole 47 by press-fitting or the like.

An end surface of the sleeve 2 facing the first side in the axial direction (hereinafter referred to as a first-side sleeve end surface 16) is coplanar with an end surface of the rotor core 4 facing the first side in the axial direction (hereinafter referred to as a first-side core end surface 48). An end surface of the sleeve 2 facing the second side in the axial direction (hereinafter referred to as a second side sleeve end surface 17) is coplanar with an end surface of the rotor core 4 facing the second side in the axial direction (hereinafter referred to as a second side core end surface 49). The sleeves 2 are disposed in the respective communication holes 47.

Here, the coil end portion 34 protruding to the first side is positioned axially outward with respect to the first side sleeve end surface 16 and the first side core end surface 48.

The coil end portion 35 protruding to the second side is positioned axially outward of the second side sleeve end surface 17 and the second side core end surface 49.

Since each sleeve 2 has the same configuration, the following description will be given by taking 1 sleeve 2 as an example.

The sleeve 2 is formed with a coolant flow field 20 through which a coolant flows. The coolant flow field 20 includes a sleeve connection path (connection path) 28, a first coolant conveyance path 22, and a second coolant conveyance path 23.

The sleeve connection passage 28 extends in the radial direction at the axial center portion of the sleeve 2.

The radially inner end of the sleeve connection passage 28 opens to the outer peripheral surface of the sleeve 2. The radially inner end of the sleeve connecting passage 28 communicates with the radially outer end of the core connecting passage 45 of the rotor core 4. Further, the radially outer end portion of the sleeve connection passage 28 terminates inside the sleeve 2.

In the present embodiment, the core connecting passage 45 and the coolant flow field 20 of the sleeve 2 form the rotor internal flow field 12.

The first cooling medium supply passage 22 extends from the sleeve connection passage 28 toward the first side in the axial direction.

The first cooling medium transport path 22 has a first inclined portion 26 and a first outlet portion 24.

The first inclined portion 26 extends radially outward from the upstream end portion (the center portion in the axial direction) toward the downstream end portion (the first end portion in the axial direction). An upstream end of the first inclined portion 26 communicates with a radially outer end of the sleeve connecting passage 28. In the present embodiment, the first inclined portion 26 has the same inner diameter over the entire range in the axial direction and is inclined outward in the radial direction over the entire range in the axial direction.

The first outlet 24 opens in the sleeve 2 at the first side sleeve end face 16.

The first outlet portion 24 is connected to a downstream side end portion of the first inclined portion 26. The first outlet 24 is formed in a circular shape in cross section.

The second cooling medium supply passage 23 extends from the sleeve connection passage 28 toward the second side in the axial direction.

The second cooling medium conveyance path 23 has a second slope portion 27 and a second outlet portion 25.

The second inclined portion 27 extends radially outward from the upstream end (center portion in the axial direction) toward the downstream end (second side end in the axial direction). An upstream end of the second inclined portion 27 communicates with a radial outer end of the sleeve connecting passage 28. In the present embodiment, the second inclined portion 27 has the same inner diameter over the entire range in the axial direction and is inclined outward in the radial direction over the entire range in the axial direction.

The second outlet portion 25 opens at the second side sleeve end face 17 in the sleeve 2.

The second outlet portion 25 is connected to a downstream side end portion of the second inclined portion 27. The second outlet portion 25 is formed to have a circular cross section.

The first coolant conveyance path 22 and the second coolant conveyance path 23 are symmetrical with respect to the axial center of the liner 2. Further, the first cooling medium transport passage 22 and the second cooling medium transport passage 23 communicate with each other at the upstream side end portion. Therefore, the coolant flowing from the sleeve connection passage 28 can flow into either one of the first coolant conveyance passage 22 and the second coolant conveyance passage 23.

In the present embodiment, the rotor internal flow path 12 (in particular, the coolant supply paths 22 and 23) and the magnet 6 extend in the axial direction in a state of being at least partially overlapped in a side view seen in the radial direction.

(action and Effect of rotating Electrical machine)

Next, the operation of the rotating electric machine 1 will be described.

The cooling medium flowing through the shaft core cooling passage 15 of the output shaft 5 flows into the radial flow passage 14 by a centrifugal force generated by the rotation of the rotor 7. The coolant flowing into the radial flow channels 14 flows radially outward in the radial flow channels 14. Then, the cooling medium flowing through the radial flow channels 14 flows into the core connecting channel 45 of the rotor core 4.

The cooling medium flowing into the core connecting passage 45 flows radially outward inside the core connecting passage 45 by centrifugal force. Subsequently, the cooling medium flowing through the core connecting passage 45 flows into the cooling medium flow passage 20 of the sleeve 2. Specifically, the cooling medium in the core connecting passage 45 first flows into the sleeve connecting passage 28. Next, the cooling medium flowing through the sleeve connection passage 28 is distributed to the first cooling medium delivery passage 22 and the second cooling medium delivery passage 23 of the rotor core 4 at the outer end portion in the radial direction of the sleeve connection passage 28. The cooling medium flowing into the first cooling medium conveyance path 22 is transferred by centrifugal force to an outward wall surface located mainly radially outward of the wall surfaces of the first inclined portion 26, moves from the upstream end portion toward the downstream end portion, and is discharged from the first outlet portion 24 opening to the first sleeve end surface 16 of the rotor core 4. The cooling medium flowing into the second cooling medium conveyance path 23 is transferred by centrifugal force to an outward wall surface located mainly radially outward of the wall surfaces of the second inclined portion 27, moves from the upstream end portion toward the downstream end portion, and is discharged from the second outlet portion 25 opened to the second side liner end surface 17 of the rotor core 4.

The cooling medium flowing through the cooling medium supply paths 22 and 23 exchanges heat with the rotor core 4 and the magnet 6 via the sleeve 2 while flowing through the cooling medium supply paths 22 and 23. This allows the rotor core and the magnets to be cooled. In particular, in the present embodiment, since the magnets 6 are arranged along the rotor internal flow path 12, heat generated in the magnets 6 is transferred to the rotor core 4 and is absorbed by the cooling medium flowing through the rotor internal flow path 12.

This enables the cooling medium to effectively cool the magnets 6 housed in the rotor core 4.

As described above, in the present embodiment, the cooling medium conveyance paths 22 and 23 are configured to have the inclined portions 26 and 27 at least in part.

According to this configuration, the cooling medium is easily guided to the outlet portions 24 and 25 by the centrifugal force generated by the rotation of the rotor 7. This allows the cooling medium to stably flow inside the rotor 7 without accumulating in the cooling medium conveyance paths 22 and 23. Therefore, the low-temperature cooling medium is easily supplied to the rotor 7, and the cooling efficiency of the rotor 7 can be improved.

Here, a force toward the first side in the axial direction acts on the cooling medium flowing through the inclined portion 26 of the first cooling medium conveyance path 22 due to a component force of the centrifugal force. Thereby, the cooling medium discharged from the first cooling medium conveyance path 22 is accelerated toward the first side in the axial direction. Therefore, the coolant discharged from the first coolant conveyance path 22 is scattered outward in the axial direction from the first sleeve end face 16 of the rotor core 4. The cooling medium discharged from the first cooling medium conveyance path 22 is guided radially outward by centrifugal force, is scattered, and is supplied to the coil end portion 34 located on the first side in the axial direction with respect to the stator core 30.

Similarly, a force toward the second side in the axial direction acts on the cooling medium flowing through the inclined portion 27 of the second cooling medium conveyance path 23 due to a component force of the centrifugal force. Thereby, the cooling medium discharged from the second cooling medium conveyance path 23 is accelerated toward the second side in the axial direction. Therefore, the cooling medium discharged from the second cooling medium conveyance path 23 is scattered outward in the axial direction from the second side sleeve end surface 17 of the rotor core 4. The cooling medium discharged from the second cooling medium conveyance path 23 is guided radially outward by centrifugal force, is scattered, and is supplied to the coil end portion 35 located on the second side in the axial direction with respect to the stator core 30.

In particular, in the present embodiment, since the coil end portions 34 and 35 are positioned axially outward of the core end surfaces 48 and 49 (the sleeve end surfaces 16 and 17), the cooling medium discharged from the end surface of the rotor core 4 is easily blown to the coil end portions 34 and 35. This allows the cooling medium to be directly sprayed to the coil end portions 34 and 35 of the coil 32 having a large heat generation amount, thereby efficiently cooling the coil 32. Further, since the cooling medium is scattered in the axial direction in the direction separating from each other from the core end faces 48 and 49 of the rotor core 4, the cooling medium can be prevented from entering the gap between the stator 3 and the rotor 7.

Therefore, the cooling efficiency can be improved, and the cooling medium can be made less likely to enter the gap between the stator 3 and the rotor 7, thereby enabling the high-performance rotating electric machine 1 to be formed.

In the present embodiment, as described above, the cooling medium is accelerated in the direction separating from the rotor 7 in the axial direction while flowing through the rotor internal flow path 12. Therefore, for example, it is not necessary to provide guides or the like for guiding the cooling medium from the end face of the rotor 7 to the outside in the axial direction on the core end faces 48 and 49 of the rotor core 4. Therefore, the rotor 7 can be simplified and the number of components can be reduced as compared with the case where the guide portion is provided on the outer side of the rotor core 4.

Therefore, the cooling efficiency can be improved by a simple structure.

Here, since the core connection path 45 and the sleeve connection path 28 are provided in the axial center portion of the rotor core 4, the cooling medium is easily distributed and supplied equally to the first cooling medium conveyance path 22 and the second cooling medium conveyance path 23 after passing through the core connection path 45 and the sleeve connection path 28. This can suppress the occurrence of a temperature difference due to imbalance in the cooling effect between the first side and the second side of the rotor 7. Further, since the rotor 7 can have a symmetrical structure with respect to the axial center portion of the rotor core 4, the weight balance of the rotor 7 can be made uniform on the first side and the second side in the axial direction. As a result, the shaft of the rotor 7 is prevented from wobbling, and the rotor 7 can be rotated stably. Further, the center of gravity can be prevented from being biased by the flow of the cooling medium in the rotor internal flow passage 12.

Further, by distributing the coolant to the coolant conveyance paths 22 and 23 from the center portion in the axial direction, the coolant at a low temperature can be supplied to the center portion in the axial direction, which is likely to become a high temperature in the rotor 7. This also suppresses the temperature gradient at the axial position of the rotor 7.

Therefore, according to the present invention, the cooling efficiency can be improved, and a stable and high-performance rotor 7 in which the bias of the rotor 7 is suppressed can be realized.

According to the present embodiment, the rotor internal flow path 12 is formed in the sleeve 2 that is separate from the rotor core 4. Therefore, as compared with the case where the rotor core 4 is directly formed with the rotor internal flow passage 12, the degree of freedom in material selection can be improved, and the processing of the rotor internal flow passage 12 can be facilitated.

Since the sleeve 2 is made of a resin product, for example, as compared with a case where the rotor internal flow path 12 is formed in a metallic sleeve 2 by laminating electromagnetic steel plates, the processing is easy and the surface of the rotor internal flow path 12 can be made smooth. This makes it possible to facilitate the flow of the cooling medium in the cooling medium flow path. Further, by selecting a resin having a high heat transfer rate as the resin used for the sleeve 2, the cooling medium flowing through the rotor internal flow path 12 formed by the sleeve 2 can cool the rotor core 4 through the resin.

Therefore, according to the present invention, the rotor 7 having easy processing and high cooling efficiency can be provided.

Further, since the weight is reduced as compared with the case of using the metal sleeve 2, it is possible to suppress the generation of stress against the centrifugal force caused by the rotation of the rotor 7.

The sleeve 2 is inserted into a plurality of communication holes 47 provided in the circumferential direction of the rotor core 4, and is disposed inside the rotor core 4. In this way, the sleeve 2 can facilitate the processing of the rotor internal flow path 12, and the communication holes 47 having the same shape in the axial direction need only be formed in the rotor core 4, so that the processing becomes easy, and the rotor core 4 can be configured to have a simple structure.

Further, since the plurality of rotor internal flow paths 12 can be easily arranged in the circumferential direction of the rotor core 4 only by inserting the sleeve 2 into the communication hole 47, it is possible to improve the cooling efficiency of the rotor 7 while suppressing a reduction in manufacturing efficiency caused by the addition of the rotor internal flow paths 12.

Therefore, according to the present invention, the rotor 7 having improved cooling efficiency and easy processing can be provided.

Next, a second embodiment to a fifth embodiment will be described with reference to fig. 6 to 18. In the second to fifth embodiments, the same members as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. In the following description, reference numerals for components other than those described in fig. 6 to 18 are referred to as appropriate in fig. 1 to 5.

(second embodiment)

A second embodiment of the present invention will be explained. Fig. 6 is a side view of a rotor core according to a second embodiment. Fig. 7 is an external perspective view of the sleeve according to embodiment 2, and fig. 8 is a cross-sectional view of the sleeve according to the second embodiment. The present embodiment is different from the above-described embodiments in that the sleeve 2 and the communication hole 47 are formed in a triangular shape in a cross-sectional view viewed from the axial direction.

In the present embodiment, the communication hole 47 having a triangular cross section is formed in the rotor core 4. The communication hole 47 is formed such that one corner of the triangular shape faces radially inward. A plurality of (8 in the present embodiment) communication holes 47 are formed in the circumferential direction.

As shown in fig. 7 and 8, the outer shape of the sleeve 2 is formed in a triangular shape in a cross-sectional view from the axial direction. Further, the sleeve connection path 28 is provided at one corner of the triangular shape. When the sleeve 2 is inserted into the rotor core 4, a corner portion of the sleeve 2 having the sleeve connection passage 28 is arranged to coincide with a corner portion of the communication hole 47 facing radially inward in the rotor core 4.

As in the first embodiment, the cooling medium supply passages 22 and 23 extend radially outward as they go axially outward. In the present embodiment, the cooling medium supply paths 22 and 23 extend toward opposite sides of the sleeve 2 where one corner of the sleeve connection path 28 is formed.

Since the sleeve 2 and the communication hole 47 are formed in a triangular shape in cross section, when the sleeve 2 is inserted into the communication hole 47 of the rotor core 4, the core connection path 45 and the sleeve connection path 28 can be easily positioned only by aligning and assembling the corner portions of the sleeve 2 and the corner portions of the communication hole 47. This can suppress the occurrence of erroneous assembly. Further, since the sleeve 2 can be prevented from rotating in the communication hole 47, the reliability of the coolant flow field 20 can be ensured over a long period of time.

(first modification of the second embodiment)

Fig. 9 is an external perspective view of a sleeve according to a first modification of the second embodiment.

The first modification is different from the above-described embodiment in that two first coolant supply passages 22 and two second coolant supply passages 23 are formed in the liner 2. As shown in fig. 9, the jacket 2 has two first cooling medium supply paths 22, two second cooling medium supply paths 23, two first outlets 24, and two second outlets 25, 25.

The first cooling medium transport paths 22, 22 extend in a direction radially outward and circumferentially away from each other with a first side in the axial direction.

The second cooling medium supply passages 23, 23 extend in a direction radially outward and circumferentially away from each other with a second side in the axial direction.

The first outlet portion 24, 24 opens at the first side sleeve end face 16. The first outlets 24, 24 are arranged in parallel with a surface facing a corner having the sleeve connecting passage 28. One of the two first coolant passages 22, 22 has the first coolant passage 22 that communicates the sleeve connection passage 28 with the first outlet 24. The other first cooling medium supply passage 22 communicates the sleeve connection passage 28 with the other first outlet port 24.

The second outlet portion 25, 25 opens at the second side sleeve end face 17. The second outlet portions 25, 25 are arranged substantially parallel to a surface facing a corner portion having the sleeve connection passage 28. One of the two second cooling medium supply paths 23, 23 has the second cooling medium supply path 23 communicating with the sleeve connection path 28 and the second outlet 25. The other second cooling medium supply passage 23 communicates with the sleeve connection passage 28 and the other second outlet port 25, respectively. The first outlets 24, 24 and the second outlets 25, 25 formed in the same liner 2 may be arranged in the circumferential direction.

According to this configuration, the coolant can be distributed in the circumferential direction, as compared with a case where one coolant transport passage is formed for each of the first coolant transport passage 22 and the second coolant transport passage 23. This facilitates uniform cooling of the rotor 7 in the circumferential direction. Therefore, the rotor 7 can be efficiently cooled. Further, since the cooling medium is scattered over a wide range in the circumferential direction, the cooling medium can be supplied over a wide range over the entire coil end portions 34 and 35. Therefore, the coil 32 can be efficiently cooled.

(third embodiment)

Next, a third embodiment of the present invention will be described. Fig. 10 is a side view of a rotor core of a third embodiment. Fig. 11 is an external perspective view of a sleeve according to a third embodiment, and fig. 12 is a sectional view of the sleeve according to the third embodiment. The present embodiment is different from the above-described embodiments in that the sleeve 2 and the communication hole 47 are formed in a trapezoidal shape in a cross-sectional view viewed from the axial direction.

In the present embodiment, the rotor core 4 is formed with a communication hole 47 having an isosceles trapezoidal cross section. The communication hole 47 is formed such that one of the opposing bottom surfaces (the bottom surface on the short side in the present embodiment) faces radially inward. A plurality of (8 in the present embodiment) communication holes 47 are formed in the circumferential direction.

As shown in fig. 11 and 12, the sleeve 2 is formed to have an isosceles trapezoid-shaped outer shape in cross section. The sleeve connection path 28 is provided on one bottom surface (the bottom surface on the short side in the present embodiment). The sleeve is disposed in the communication hole 47 so that the bottom surface on the short side matches the bottom surface on the short side of the communication hole 47.

As in the first embodiment, the cooling medium supply passages 22 and 23 extend radially outward as they go axially outward. In the present embodiment, the coolant conveyance paths 22 and 23 extend toward the other bottom surface (in the present embodiment, the bottom surface on the long side).

According to the present embodiment, the attachment direction of the sleeve 2 is uniquely determined with respect to the communication hole 47 of the rotor core 4. Therefore, the sleeve 2 can be easily positioned, and the mountability can be improved.

(first modification of the third embodiment)

Fig. 13 is an external perspective view of a sleeve according to a first modification of the third embodiment.

The first modification is different from the above-described embodiment in that the outlet portions 24 and 25 of the liner 2 are formed in an elongated hole shape. As shown in fig. 13, the outlet portions 24 and 25 are formed as long holes having long axes in a direction substantially perpendicular to the radial direction.

According to the present configuration, since the first outlet 24 and the second outlet 25 extend in the circumferential direction, the cooling medium can be distributed over a wide range in the circumferential direction. This facilitates uniform cooling of the rotor in the circumferential direction. Therefore, the rotor 7 can be efficiently cooled. Further, since the cooling medium continuously scatters over a wide range in the circumferential direction, the cooling medium can be supplied over a wide range over the entire coil end portions 34 and 35. Therefore, the coil 32 can be efficiently cooled.

(fourth embodiment)

Next, a fourth embodiment of the present invention will be described. Fig. 14 is a side view of a rotor core according to a fourth embodiment. Fig. 15 is an external perspective view of a sleeve according to a fourth embodiment, and fig. 16 is a sectional view of the sleeve according to the fourth embodiment. The present embodiment is different from the above-described embodiments in that the sleeve 2 and the communication hole 47 are formed in an arc shape centering on the axis C of the rotor core 4 in a cross-sectional view viewed from the axial direction.

In the present embodiment, the rotor core 4 is formed with the communication hole 47 having an arc-shaped cross section.

Specifically, the communication hole 47 is formed by 4 sides of an outer circular arc portion, an inner circular arc portion, one side surface portion, and the other side surface portion, in a cross-sectional view seen from the axial direction. The arc center of the outer circumferential arc portion coincides with the axis C of the rotor core 4. The arc center of the inner circular arc portion coincides with the axis C of the rotor core 4, and the inner circular arc portion is located radially inward of the outer circular arc portion. The one-side surface portion extends in the radial direction and connects circumferential end portions of the outer circular arc portion and the inner circular arc portion. The other side surface portion extends in the radial direction and connects the circumferential other end portions of the outer circular arc portion and the inner circular arc portion. A plurality of (4 in the present embodiment) communication holes 47 are formed in the circumferential direction.

As shown in fig. 15 and 16, the sleeve 2 is formed to have an arc-shaped outer shape in cross section. The sleeve connection passage 28 is provided in an arc-shaped inner circumferential arc portion. Thereby, the mounting direction of the sleeve 2 is uniquely determined with respect to the communication hole 47 of the rotor core 4. Therefore, the sleeve 2 can be easily positioned, and the mountability can be improved.

In the present embodiment, the first cooling medium conveyance path 22 and the second cooling medium conveyance path 23 are formed in an arc shape along the outer circumferential arc portion in a cross-sectional view seen from the axial direction. The cross-sectional shapes of the first cooling medium transport passage 22 and the second cooling medium transport passage 23 are uniform from the upstream end to the downstream end. In this way, since the first cooling medium conveyance path 22 and the second cooling medium conveyance path 23 are formed to have an arc-shaped cross section, the cooling medium is discharged from the outlet portions 24 and 25 with a width in the circumferential direction. Therefore, the cooling medium can be supplied over a wide range over the entire coil end portions 34 and 35.

(fifth embodiment)

Next, a fifth embodiment of the present invention will be described. Fig. 17 is a partial cross-sectional view of a rotary electric machine showing a rotor cooling structure according to a fifth embodiment. The present embodiment is different from the above-described embodiments in that the rotor internal flow path 12 is directly formed in the rotor core 4.

In the present embodiment, the rotor core 4 is provided with the rotor internal flow path 12. The rotor internal flow path 12 includes a core connection path 45, a first cooling medium conveyance path 22, and a second cooling medium conveyance path 23. The plurality of rotor internal flow passages 12 are arranged at intervals in the circumferential direction. The cooling medium flowing through the shaft core cooling passage 15 of the output shaft 5 can flow through the rotor internal flow passage 12 as the rotor 7 rotates.

The core connection path 45 extends in the radial direction at the center in the axial direction inside the rotor core 4. The radially inner end of the core connecting passage 45 opens on the inner circumferential surface of the shaft through hole 41. The radially inner end of the core connecting passage 45 communicates with the radially outer end of the radial flow passage 14 of the output shaft 5. The cooling medium flowing through the radial flow channels 14 can flow into the core connecting channel 45.

Further, the outer end portion in the radial direction of the core connecting path 45 is terminated inside the rotor core 4.

The first cooling medium supply passage 22 is provided on a first side in the axial direction of the rotor core 4. The first cooling medium transport passage 22 extends radially outward from the upstream end toward the downstream end. The upstream end of the first cooling medium supply passage 22 communicates with the radial outer end of the core connecting passage 45. The downstream end of the first cooling medium feeding path 22 opens at a first core end surface 48 of the rotor core 4.

The second cooling medium supply passage 23 is provided on the second side of the rotor core 4 in the axial direction. The second cooling medium transport passage 23 extends radially outward from the upstream end toward the downstream end. The upstream end of the second cooling medium supply passage 23 communicates with the radially outer end of the core connecting passage 45. The downstream end of the second cooling medium supply passage 23 opens at a second side core end face 49 of the rotor core 4.

The first cooling medium conveyance path 22 and the second cooling medium conveyance path 23 are symmetrical with respect to the center portion in the axial direction. Further, the upstream end of the first cooling medium conveyance path 22 and the upstream end of the second cooling medium conveyance path 23 communicate with each other. Therefore, the cooling medium flowing from the core connecting passage 45 can flow into either the first cooling medium conveyance passage 22 or the second cooling medium conveyance passage 23.

When the rotor core 4 according to the present embodiment is formed by laminating electromagnetic steel sheets, for example, first, the electromagnetic steel sheets are formed with cooling medium holes to be the cooling medium passages 22 and 23. At this time, the coolant holes are formed so that the electromagnetic steel sheets arranged at the center in the axial direction of the rotor core 4 are positioned radially inward as the electromagnetic steel sheets constituting the rotor core 4 are positioned farther in the axial direction. Thereafter, electromagnetic steel sheets having different positions of formation of the cooling medium holes in the radial direction are stacked coaxially along the axis C. Thereby, the rotor core 4 having the rotor internal flow path 12 is formed.

In the present embodiment, the same operational effects as those of the above-described embodiment can be obtained, and workability can be improved by reducing the number of components and omitting the step of fixing the sleeve 2, as compared with the case of providing the sleeve 2. In addition, the rotor core 4 can be directly cooled by the cooling medium.

(first modification of fifth embodiment)

As a first modification of the fifth embodiment, for example, as shown in fig. 18, the entire inner portions in the radial direction of the cooling medium conveyance paths 22 and 23 may be constituted by the straight portions 29.

In the first modification, the first cooling medium conveyance path 22 includes the first inclined portion 26 and the linear portion 29. The first inclined portion 26 is formed at a radially outer portion of the first cooling medium conveyance path 22. The straight portion 29 is formed in a radially inner portion of the first cooling medium conveyance path 22. Thus, the first cooling medium transport passage 22 gradually increases in inner diameter from the upstream end toward the downstream end.

The second cooling medium conveyance path 23 includes a second inclined portion 27 and a linear portion 29. The second inclined portion 27 is formed at a radially outer portion of the second cooling medium conveyance path 23. The straight portion 29 is formed in a radially inner portion of the second cooling medium conveyance path 23. Thus, the second cooling medium transport passage 23 gradually increases in inner diameter from the upstream end toward the downstream end.

Preferably, the linear portion 29 of the first cooling medium conveyance path 22 is spaced apart from the rotor core 4 in the radial direction by the same distance as the linear portion 29 of the second cooling medium conveyance path 23 is spaced apart from the rotor core 4 in the radial direction.

In this way, the inclined portions 26 and 27 may be formed at least in part of the outer portions in the radial direction of the cooling medium passages 22 and 23. In addition, when the sleeve 2 is used, the radially inner portion may be the linear portion 29 in the same manner.

Thus, for example, when the rotor core 4 and the sleeve 2 are formed by a dust core or a mold, the cooling medium supply paths 22 and 23 can be easily processed.

The preferred embodiments of the present invention have been described above, but the present invention is not limited to these embodiments. Addition, omission, replacement, and other changes in configuration may be made within the scope not departing from the spirit of the present invention. The present invention is not limited by the foregoing description, but is only limited by the scope of the claims.

For example, in the above-described embodiment, the case where the sleeve 2 is made of a resin product has been described, but the present invention is not limited to this configuration. The sleeve 2 may also be metal. In this case, the sleeve 2 is formed by laminating steel plates in the axial direction, for example. Alternatively, the two members may be divided in the axial direction.

In the above-described embodiment, the outer shape of the sleeve 2 in plan view is a perfect circle, a triangle, a trapezoid, an arc, or the like, but the present invention is not limited to this configuration. The sleeve 2 may have a circular shape other than a perfect circle (for example, an ellipse or an oblong), or may have a shape other than the above-described shape such as a triangular shape or a polygonal shape other than a trapezoidal shape. When the sleeve 2 is formed in a shape other than a perfect circle, the sleeve 2 has portions having different distances from the center of gravity of the sleeve 2 when viewed in a cross section taken from the axial direction, and thus, as described above, the rotation stop and the erroneous assembly of the sleeve 2 with respect to the rotor core 4 can be suppressed.

In the above-described embodiment, the end plates are not provided on the core end faces 48 and 49 of the rotor core 4, but the present invention is not limited to this configuration. An end plate may be provided on either or both of the core end faces 48 and 49 of the rotor core 4. In this case, it is preferable that the end plate is provided with holes for discharging the cooling medium at positions corresponding to the outlets 24, 25.

In the above-described embodiment, the inclined portions 26 and 27 are formed over the entire axial direction, but the inclined portions 26 and 27 may be formed at least in part of the section from the sleeve connecting passage 28 to the outlet portions 24 and 25.

In the above-described embodiment, the configuration in which the coolant flow field 20 branches from the center portion in the axial direction to the coolant conveyance paths 22 and 23 has been described, but the present invention is not limited to this configuration. For example, the sleeve connection passage 28 may be formed at the first axial end portion, and the cooling medium delivery passage 23 may extend radially outward from the first axial end portion toward the second axial end portion.

In the above-described embodiment, the case where the rotor core 4 is formed by laminating the electromagnetic steel sheets has been described, but the present invention is not limited to this configuration. The rotor core 4 may be a so-called dust core, or may be formed using a so-called 3D printer. That is, in the 3D printer, the rotor core 4 can be molded by selectively melting and solidifying the powder layer in which the metal powder is supplied in a layer form based on the sectional data of the rotor core.

In the above-described embodiment, the configuration in which the sleeve 2 is disposed in the communication hole 47 has been described, but the present invention is not limited to this configuration. For example, the rotor core 4 may have an inner cylinder fitted to the output shaft 5 and an outer cylinder surrounding the inner cylinder, and a cylindrical sleeve may be disposed between the inner cylinder and the outer cylinder.

In the above-described embodiment, the case where the rotor core 4 and the sleeve 2 are formed separately has been described, but the present invention is not limited to this configuration, and the sleeve 2 may be integrally formed with the rotor core 4 by insert molding or the like.

Claims

1. A rotor, characterized in that,

the rotor is provided with:

an output shaft configured to be rotatable about an axis and having a shaft core cooling passage through which a cooling medium flows; and

a rotor core fixed to the output shaft and having a rotor internal flow path,

an upstream end of the rotor internal flow path communicates with the shaft core cooling path, and a downstream end of the rotor internal flow path opens at an end surface of the rotor core facing the axial direction,

the rotor internal flow path has, at least in part, an inclined portion extending radially outward from the upstream end portion toward the downstream end portion.

2. The rotor of claim 1,

the rotor internal flow path includes:

a connection passage communicating with the shaft core cooling passage;

a first cooling medium supply passage extending from the connection passage toward a first side in an axial direction, the downstream end of the first cooling medium supply passage being open at an end surface of the rotor core on the first side; and

a second cooling medium supply passage extending from the connection passage toward a second side in the axial direction, the downstream end of the second cooling medium supply passage being open at an end surface of the rotor core on the second side,

the connecting passage is provided at the axial center portion,

the first cooling medium transport path and the second cooling medium transport path each have the inclined portion at least in part.

3. The rotor of claim 2,

the inclined portion is provided in the first cooling medium conveyance path and the second cooling medium conveyance path over the entire axial direction.

4. The rotor of any one of claims 1 to 3,

a sleeve is separately attached to the rotor core, and the sleeve forms the rotor internal flow path.

5. The rotor of claim 4,

the sleeve is a resin article.

6. The rotor according to any one of claims 4 or 5,

the rotor core has a plurality of communication holes formed in a circumferential direction, and the sleeve is disposed in the plurality of communication holes.

7. The rotor of claim 6,

the communication hole and the sleeve are formed in a polygonal shape in a plan view when viewed in the axial direction.

8. The rotor of claim 6,

the communication hole and the sleeve are formed in an arc shape centered on the axis in a plan view seen in the axial direction.

9. The rotor of any one of claims 1 to 8,

magnets are disposed along the axial direction at positions in the rotor core where at least a part of the magnets overlaps the rotor internal flow path in a side view from the radial direction.

10. A rotating electrical machine is characterized in that,

the rotating electric machine includes:

the rotor of any one of claims 1 to 9; and

a stator surrounding the rotor.

11. The rotating electric machine according to claim 10,

the stator includes:

a stator core; and

a coil that is assembled to the stator core and has coil end portions that protrude from both end surfaces in the axial direction in the stator core,

the coil end portion is located on the outside in the axial direction with respect to an end surface on the first side in the axial direction and an end surface on the second side in the axial direction in the rotor core.