ROTOR, ROTATING ELECTRIC MACHINE, DRIVE DEVICE, AND MOBILE BODY

Abstract

To provide a technique attaining reduction of torque ripple and improvement of manufacture efficiency for a rotor having a skew structure.SOLUTION: A first rotor core 11 and a second rotor core, which are aligned in an axial direction and arranged with magnet poles thereof positioned deviated from each other in a circumferential direction, comprise: a pair of first magnets 13; and a pair of first magnet storage holes 14 in which the first magnets are stored. A flux barrier of the first rotor core includes a first flux barrier 31 and a second flux barrier 32 which are overlapped with the first magnet storage holes of the second rotor core in the axial direction. An imaginary line connecting an intermediate position of the pair of first magnets in the circumferential direction with a central axis is defined to be a first axis J1, and an imaginary line being adjacent with the first axis in the circumferential direction and magnetically orthogonal with the first axis and passing the central axis is defined to be a second axis J2. The first flux barrier is disposed between the first axis and the first magnet in the circumferential direction, and the second flux barrier is disposed on the second axis.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present disclosure relates to a rotor, a rotating electric machine, a drive device, and a moving body. [Background technology]

[0002] Conventionally, a laminated rotor core is known that is manufactured by fixing a permanent magnet to a laminated body by resin sealing (see, for example, Patent Document 1). In addition, in a rotating electric machine having a permanent magnet rotor, the rotor is given a skew structure in order to reduce cogging torque (see, for example, Patent Document 2). In a skew structure, a laminated rotor core is divided into multiple pieces together with the permanent magnet in the lamination direction, and each divided rotor core is assembled with a predetermined angle offset.

[0003] The permanent magnets are inserted into the magnet insertion sections of the rotor core and fixed in place with adhesive using a filler. In a skewed structure, the positions of the magnet insertion sections are misaligned between the split rotor cores, so when filling the magnet insertion sections with filler after stacking multiple split rotor cores, there is a possibility that the magnet insertion sections will not be filled sufficiently with filler. For this reason, conventionally, the magnet insertion sections are filled with filler for each divided tier. In this case, the work must be repeated for each divided tier, which raises concerns that the manufacturing process may become complicated.

[0004] For this reason, it is known that a rotor having a skewed rotor core that is divided into multiple stages in the axial direction and arranged with a circumferential phase angle between each stage, and permanent magnets that create poles, is configured as follows (see Patent Document 2, for example). The rotor core has insertion holes for inserting the permanent magnets, and at least one intermediate hole that is provided between the poles and independent of the insertion holes. The rotor core insertion hole in a certain stage communicates with the intermediate hole in an adjacent stage. With this configuration, the intermediate hole ensures a supply path for filler to the permanent magnet insertion holes, so that a rotor having a skewed rotor core can be manufactured at low cost. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2007-282392 A [Patent Document 2] JP 2011-55641 A Summary of the Invention [Problem to be solved by the invention]

[0006] In the above-mentioned configuration in which an intermediate hole is provided between the poles formed by the permanent magnets, the intermediate hole may affect magnetic characteristics such as torque ripple depending on, for example, the angle or skew angle of the permanent magnets.

[0007] An object of the present disclosure is to provide a technique that can reduce torque ripple and improve manufacturing efficiency in a rotor having a skew structure. [Means for solving the problem]

[0008] An exemplary rotor of the present disclosure is a rotor that rotates around a central axis, and has a first rotor core and a second rotor core that are arranged in the axial direction and have magnetic poles that are shifted from each other in the circumferential direction. Each of the first rotor core and the second rotor core is arranged in a V-shape with a circumferential distance increasing toward the radially outward direction, and has a pair of first magnets that constitute the magnetic poles, and a pair of first magnet accommodating holes that accommodate the pair of first magnets. The first rotor core further has a plurality of flux barriers that penetrate in the axial direction. The plurality of flux barriers include a first flux barrier and a second flux barrier that at least partially overlap in the axial direction with the first magnet accommodating hole of the second rotor core. In a plan view from the axial direction, a virtual line connecting a circumferential midpoint of the pair of first magnets and the central axis is defined as a first axis, and a virtual line that is adjacent to the first axis in the axial direction, magnetically perpendicular to the first axis, and passes through the central axis is defined as a second axis. The first flux barrier is disposed circumferentially between the first shaft and the first magnet, and the second flux barrier is disposed on the second shaft.

[0009] An exemplary rotating electric machine according to the present disclosure includes a rotor having the above-described configuration and a stator disposed radially outward of the rotor.

[0010] An exemplary drive device of the present disclosure includes a rotating electric machine having the above-described configuration and a gear unit connected to the rotating electric machine.

[0011] An exemplary moving body of the present disclosure includes a driving device having the above-described configuration, and a moving operation unit that is connected to the driving device and enables the moving body itself to move. Effect of the Invention

[0012] According to the present disclosure, in a rotor having a skew structure, it is possible to reduce torque ripple and improve manufacturing efficiency. [Brief description of the drawings]

[0013] [Figure 1]FIG. 1 is a schematic diagram showing a configuration of a moving body according to an embodiment of the present disclosure. [Diagram 2] FIG. 2 is a diagram illustrating a schematic configuration of a drive device according to an embodiment of the present disclosure. [Diagram 3] FIG. 3 is a side view that illustrates a schematic configuration of the rotor according to the first embodiment of the present disclosure. [Figure 4] FIG. 4 is a plan view showing a schematic configuration of a first rotor core of the rotor according to the first embodiment. [Diagram 5] FIG. 5 is a plan view that typically shows a detailed configuration of the first rotor core shown in FIG. [Figure 6] FIG. 6 is a diagram showing the relationship between the first rotor core shown in FIG. 5 and the second rotor core disposed below the first rotor core. [Figure 7] FIG. 7 is a plan view that illustrates a schematic configuration of a portion of the first rotor core after the resin is injected. [Figure 8] FIG. 8 is a diagram for explaining the details of the arrangement of the first flux barrier and the second flux barrier. [Figure 9] FIG. 9 is a graph showing the results of an experiment to explain the arrangement of the second flux barrier. [Figure 10] FIG. 10 is a plan view showing the configuration of a first rotor core of a rotor according to the second embodiment. [Figure 11] FIG. 11 is a diagram showing the relationship between the first rotor core shown in FIG. 10 and the second rotor core disposed below the first rotor core. [Figure 12] FIG. 12 is a plan view that illustrates a schematic configuration of a portion of the first rotor core after the resin is injected. [Figure 13] FIG. 13 is a diagram for explaining details of the arrangement of a plurality of flux barriers included in the first rotor core according to the second embodiment. [Figure 14] FIG. 14 is a graph showing the results of an experiment to explain the arrangement of the third flux barrier. [Figure 15] FIG. 15 is a first graph showing experimental results for explaining the arrangement of the fourth flux barrier. [Figure 16] FIG. 16 is a second graph showing the experimental results for explaining the arrangement of the fourth flux barrier. [Figure 17] FIG. 17 is a diagram for explaining a second rotor core of the rotor according to the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, an exemplary embodiment of the present disclosure will be described in detail with reference to the drawings. In this specification, when describing the rotating electric machine and the rotor, the direction in which the central axis A of the rotating electric machine 100 shown in FIG. 2 extends will be simply referred to as the "axial direction", and the radial direction and circumferential direction centered on the central axis A of the rotating electric machine 100 will be simply referred to as the "radial direction" and the "circumferential direction". In addition, in this specification, when describing the rotor, the axial direction when the rotating electric machine 100 is arranged in the direction shown in FIG. 2 will be defined as the up-down direction. In addition, in this specification, when viewed from above in the axial direction, the clockwise side of the circumferential direction will be defined as one side of the circumferential direction, and the counterclockwise side of the circumferential direction will be defined as the other side of the circumferential direction. In addition, the definitions of the up-down direction, one side of the circumferential direction, and the other side of the circumferential direction are names used simply for explanation, and do not limit the actual positional relationship or direction.

[0015] <1. Moving body, driving device, and rotating electric machine> 1 is a schematic diagram showing a configuration of a moving body 300 according to an embodiment of the present disclosure. In this embodiment, the moving body 300 is an automobile. However, the moving body 300 may be a vehicle other than an automobile, a ship, an aircraft, a robot, or the like. As shown in FIG. 1, the moving body 300 has a driving device 200 and a moving operation unit 301.

[0016] The traveling motion unit 301 is connected to the driving device 200, and allows the traveling motion unit 301 to move. In detail, the traveling motion unit 301 is a wheel fixed to an axle 302. The axle 302 may be configured to be connected to the driving device 200, or may be configured to be included in the driving device 200, for example. The traveling motion unit 301 rotates about the axle 302 by being driven by the driving device 200. In accordance with the rotation of the traveling motion unit 301, the moving body 300 moves.

[0017] Note that the driving device 200 may be disposed anywhere in the moving body 300 as long as it can be directly or indirectly connected to the traveling motion unit 301. The driving device 200 may be a device that constitutes a so-called in-wheel motor.

[0018] 2 is a diagram illustrating a schematic configuration of a drive device 200 according to an embodiment of the present disclosure. As illustrated in FIG. 2, the drive device 200 includes a rotating electric machine 100 and a gear unit 201 connected to the rotating electric machine 100.

[0019] In this embodiment, the rotating electric machine 100 is a motor. The drive device 200 has an inverter (not shown) that supplies power to the rotating electric machine 100. However, the technology of the present disclosure may be applied to a configuration in which the rotating electric machine is used as a generator. The rotating electric machine 100 has a rotor 10 and a stator 20 disposed radially outward of the rotor 10. That is, the rotating electric machine 100 of this embodiment is an inner rotor type rotating electric machine.

[0020] The rotor 10 rotates about a central axis A. The rotor 10 has a cylindrical shape centered on the central axis A. The rotor 10 has a magnet for a field magnet embedded therein, as will be described in detail later. In other words, the rotating electric machine 100 is an IPM (Interior Permanent Magnet) type rotating electric machine.

[0021] The stator 20 is an armature of the rotating electric machine 100. The stator 20 is cylindrical and centered on the central axis A. The stator 20 faces the rotor 10 arranged radially inward with a gap therebetween, and surrounds the rotor 10. In detail, the stator 20 has a stator core 21 and a coil 22. The stator core 21 has a cylindrical core back 211 extending in the axial direction, and a plurality of teeth 212 extending radially inward from the core back 211. The coil 22 is formed by winding a conductor around the teeth 212 of the stator core 21 via an insulator (not shown). When a driving current is supplied to the coil 22, a radial magnetic flux is generated in the teeth 212 of the stator core 21. As a result, a circumferential torque is generated in the rotor 10, and the rotor 10 rotates around the central axis A.

[0022] The rotating electric machine 100 further has a columnar shaft 40 extending in the axial direction. The shaft 40 is disposed radially inward of the rotor 10 and fixed to the rotor 10. The shaft 40 rotates together with the rotor 10 about a central axis A. In this embodiment, an upper end of the shaft 40 is inserted into a casing 2011 of a gear unit 201. The gear unit 201 has a plurality of gears 2012 in the casing 2011. When the shaft 40 rotates, the rotational force of the shaft 40 is transmitted to the axle 302 by the plurality of gears 2012.

[0023] In this embodiment, the rotating electric machine 100 is configured to be connected to the traveling motion unit 301 via the gear unit 201, but may be directly connected to the traveling motion unit 301.

[0024] As described below, according to the present disclosure, the rotor 10 having a skew structure can be manufactured at low cost while reducing torque ripple. Therefore, the rotating electric machine 100, the drive unit 200, and the moving body 300 each having the rotor 10 can be manufactured at low cost while improving the characteristics.

[0025] <2. Rotor> Next, the rotor 10 will be described in detail.

[0026] (2-1. First embodiment) Fig. 3 is a side view showing a schematic configuration of the rotor 10 according to the first embodiment of the present disclosure. As shown in Fig. 3, the rotor 10 has a first rotor core 11 and a second rotor core 12 arranged in the axial direction. In this embodiment, the first rotor core 11 is arranged above and the second rotor core 12 is arranged below, with the first rotor core 11 being arranged above and the second rotor core 12 being arranged below. Note that in this embodiment, the number of rotor cores constituting the rotor 10 is two. However, the number of rotor cores constituting the rotor 10 may be any number greater than two.

[0027] Both the first rotor core 11 and the second rotor core 12 are cylindrical and centered on the central axis A. The first rotor core 11 and the second rotor core 12 have the same inner diameter and outer diameter. The first rotor core 11 and the second rotor core 12 also have the same axial length. The first rotor core 11 and the second rotor core 12 are, for example, laminated steel plates in which multiple electromagnetic steel plates are laminated in the axial direction. The multiple electromagnetic steel plates are fixed to each other by, for example, crimping or welding.

[0028] The first rotor core 11 and the second rotor core 12 have a plurality of magnetic poles in the circumferential direction. The first rotor core 11 and the second rotor core 12 have the same number of magnetic poles. In FIG. 3, a thick line TL indicates the center position of each magnetic pole in the circumferential direction. As shown in FIG. 3, the first rotor core 11 and the second rotor core 12 are arranged with the magnetic poles shifted from each other in the circumferential direction. That is, the rotor 10 has a skew structure. By configuring the rotor 10 to have a skew structure in this way, it is possible to reduce cogging torque. In this embodiment, the first rotor core 11 is arranged shifted to one side in the circumferential direction with respect to the second rotor core 12. However, the first rotor core 11 may be arranged shifted to the other side in the circumferential direction with respect to the second rotor core 12. The angle by which the first rotor core 11 and the second rotor core 12 are shifted in the circumferential direction may be any value obtained, for example, by an experiment, a simulation, or the like.

[0029] FIG. 4 is a plan view showing a schematic configuration of the first rotor core 11 of the rotor 10 according to the first embodiment. In this embodiment, the second rotor core 12 has the same configuration as the first rotor core 11, except for the configuration in which the positions of the magnetic poles are shifted in the circumferential direction. For this reason, the configuration of the second rotor core 12 may also be described together with reference to FIG. 4 showing the configuration of the first rotor core 11. In this embodiment, the first rotor core 11 and the second rotor core 12 can be manufactured using the same mold, so that the manufacturing cost can be reduced compared to the case in which the first rotor core and the second rotor core are manufactured using different molds.

[0030] As shown in FIG. 4, each of first rotor core 11 and second rotor core 12 has a pair of first magnets 13a, 13b and a pair of first magnet accommodating holes 14a, 14b.

[0031] In this embodiment, eight pairs of first magnets 13a, 13b are arranged at equal intervals in the circumferential direction in each of the first rotor core 11 and the second rotor core 12. The pair of first magnets 13a, 13b constitutes magnetic poles. That is, the first rotor core 11 and the second rotor core 12 each have eight magnetic poles. However, the number of magnetic poles may be other than eight, and the number of magnetic poles may be changed depending on, for example, the target design of the rotating electric machine 100.

[0032] The pair of first magnets 13a, 13b are arranged in a V-shape with the circumferential distance increasing toward the radially outward direction. In detail, each of the pair of first magnets 13a, 13b has a rectangular parallelepiped shape that is rectangular when viewed from the axial direction. When viewed from the axial direction, the longitudinal directions of the pair of first magnets 13a, 13b are inclined in opposite directions relative to the radial direction. The pair of first magnets 13a, 13b have the same shape and size, and are arranged symmetrically with respect to a virtual line extending radially from the central axis A when viewed from the axial direction. The pair of first magnets 13a, 13b are permanent magnets having the same magnetic properties, such as sintered magnets or bonded magnets.

[0033] The pair of first magnet accommodating holes 14a, 14b accommodate a pair of first magnets 13a, 13b. Therefore, in this embodiment, the number of pairs of first magnet accommodating holes 14a, 14b in each of the first rotor core 11 and the second rotor core 12 is eight. The number of pairs of first magnet accommodating holes 14a, 14b may be changed according to the number of pairs of first magnets 13a, 13b. The multiple pairs of first magnet accommodating holes 14a, 14b are arranged at equal intervals in the circumferential direction.

[0034] Similar to the pair of first magnets 13a, 13b, the pair of first magnet accommodating holes 14a, 14b are V-shaped with a circumferential distance increasing radially outward. In a plan view from the axial direction, the pair of first magnet accommodating holes 14a, 14b are symmetrically disposed with respect to a virtual line extending radially from the central axis A. The pair of first magnet accommodating holes 14a, 14b are through holes that axially penetrate rotor cores 11, 12 in which the accommodating holes 14a, 14b are provided.

[0035] In this embodiment, each of the pair of first magnet accommodating holes 14a, 14b has a first gap 15 at both ends in the longitudinal direction of the first magnets 13a, 13b accommodated in the corresponding accommodating holes 14a, 14b in a plan view from the axial direction. The first gap 15 functions as a flux barrier.

[0036] Fig. 5 is a plan view showing a schematic detailed configuration of the first rotor core 11 shown in Fig. 4. Fig. 5 is an enlarged view showing a portion of the first rotor core 11. As shown in Fig. 5, the first rotor core 11 further has a plurality of flux barriers 30 penetrating in the axial direction. The flux barriers 30 are through holes provided separately from the first magnet accommodating holes 14. In detail, the plurality of flux barriers 30 include a first flux barrier 31 and a second flux barrier 32.

[0037] In this embodiment, the multiple flux barriers 30 include only two types of flux barriers, a first flux barrier 31 and a second flux barrier 32. In this embodiment, the first flux barrier 31 and the second flux barrier 32 are different in shape and size from each other. However, the first flux barrier 31 and the second flux barrier 32 may be the same in shape and size. The shape of the flux barrier 30 is not particularly limited.

[0038] Fig. 6 is a diagram showing the relationship between the first rotor core 11 shown in Fig. 5 and the second rotor core 12 arranged below the first rotor core 11. In Fig. 6, the configuration related to the second rotor core 12 is indicated by dashed lines. As shown in Fig. 6, the first flux barrier 31 and the second flux barrier 32 at least partially overlap with the first magnet accommodating holes 14 of the second rotor core 12 in the axial direction.

[0039] In detail, the first flux barrier 31 at least partially overlaps in the axial direction with the first magnet accommodating hole 14a on one circumferential side of the pair of first magnet accommodating holes 14a, 14b of the second rotor core 12. The second flux barrier 32 at least partially overlaps in the axial direction with the first magnet accommodating hole 14b on the other circumferential side of the pair of first magnet accommodating holes 14a, 14b of the second rotor core 12.

[0040] In FIG. 6, black dots indicate the positions where the resin 16 is injected. FIG. 7 is a plan view showing a schematic configuration of a portion of the first rotor core 11 after the resin 16 is injected. In this embodiment, the resin 16 is injected in the same manner in each magnetic pole of the rotor 10 in which the first rotor core 11 and the second rotor core 12 are stacked. In each magnetic pole of the first rotor core 11, the resin 16 is injected into each of the pair of first magnet accommodating holes 14a, 14b, the first flux barrier 31, and the second flux barrier 32. The first flux barrier 31 and the second flux barrier 32 at least partially overlap with the first magnet accommodating hole 14 of the second rotor core 12 in the axial direction. For this reason, by injecting the resin 16 from the first rotor core 11 side, the resin 16 can be filled not only in the first magnet accommodating hole 14 of the first rotor core 11 but also in the first magnet accommodating hole 14 of the second rotor core 12.

[0041] That is, the rotor 10 of this embodiment further has a resin 16 filled in the first magnet accommodating holes 14 and the flux barrier 30. In detail, the rotor 10 has the resin 16 filled in the first magnet accommodating holes 14, the first flux barrier 31, and the second flux barrier 32. The resin 16 is, for example, an epoxy resin.

[0042] With this configuration, in each of the rotor cores 11, 12 constituting the rotor 10, the first magnets 13 can be fixed in the first magnet accommodating holes 14 using the resin 16. Furthermore, the first rotor core 11 and the second rotor core 12 can be stacked in the axial direction, and the first magnets 13 in each of the rotor cores 11, 12 can be fixed together using the resin 16, thereby improving the work efficiency during the manufacture of the rotor 10.

[0043] It is preferable that the first flux barrier 31 and the second flux barrier 32 overlap with the first magnet accommodating hole 14 as much as possible. This can improve the efficiency of filling the resin 16. In particular, the resin 16 is melted when injected, and the melted resin 16 solidifies in the first magnet accommodating hole 14 to fix the first magnet 13 to the rotor cores 11 and 12. The resin 16 may cover the upper end face of the first magnet 13 in the first magnet accommodating hole 14. In the second rotor core 12, the lower end of the first magnet 13 accommodated in the first magnet accommodating hole 14 of the second rotor core 12 does not have to be covered by the resin 16. On the lower side of the second rotor core 12, the lower end of the first magnet 13 may be arranged on the same plane as the opening edge of the first magnet accommodating hole 14 of the second rotor core 12.

[0044] As shown in FIG. 5, in plan view from the axial direction, a virtual line connecting the central axis A and the circumferential midpoint of the pair of first magnets 13a, 13b is defined as the first axis J1. In addition, in plan view from the axial direction, a virtual line adjacent to the first axis J1 in the circumferential direction, magnetically perpendicular to the first axis J1, and passing through the central axis A is defined as the second axis J2. In other words, the second axis J2 is a virtual line connecting the central axis A and the circumferential midpoint of the circumferentially adjacent first axes J1. The first axis J1 is the so-called d-axis. The second axis J2 is the so-called q-axis.

[0045] 5, the first flux barrier 31 is disposed circumferentially between the first axis J1 and the first magnet 13. In other words, the first flux barrier 31 is disposed circumferentially between the first axis J1 and the first magnet accommodating hole 14. In this embodiment, the first flux barrier 31 is disposed circumferentially between the first axis J1 and the first magnet 13a of the pair of first magnets 13a, 13b, which is on one side in the circumferential direction.

[0046] However, when the direction in which the second rotor core 12 is circumferentially shifted relative to the first rotor core 11 is the opposite direction to that of this embodiment, the first flux barrier 31 may be disposed circumferentially between the first axis J1 and the first magnet 13b on the other circumferential side of the pair of first magnets 13a, 13b. Also, another flux barrier may be provided at a position symmetrical to the first flux barrier 31 with respect to the first axis J1 of the first rotor core 11. With this configuration, it is possible to prevent the first rotor core 11 from becoming unbalanced, and the rotor 10 can be rotated stably.

[0047] 5, the second flux barrier 32 is disposed on the second axis J2. By disposing the first flux barrier 31 and the second flux barrier 32 in this manner, taking into consideration the positional relationship between the first axis J1 and the second axis J2, it is possible to dispose a plurality of flux barriers 30 at positions where torque ripple can be reduced. That is, in the rotor 10 having a skew structure, it is possible to reduce torque ripple and improve manufacturing efficiency.

[0048] Fig. 8 is a diagram for explaining the details of the arrangement of the first flux barrier 31 and the second flux barrier 32. Fig. 8 is an enlarged plan view of the first rotor core 11 similar to Fig. 5. As shown in Fig. 8, in a plan view from the axial direction, a virtual circle having a radius from the central axis A to the radially outermost end of the first magnet accommodating hole 14 is defined as a first virtual circle VC1, and a virtual circle having a radius from the central axis A to the radially outermost end of the first magnet 13 is defined as a second virtual circle VC2. As shown in Fig. 8, the second flux barrier 32 is disposed radially between the first virtual circle VC1 and the second virtual circle VC2.

[0049] 6, the first flux barrier 31 and the second flux barrier 32 are disposed symmetrically with respect to the first axis J1 of the second rotor core 12. That is, the first flux barrier 31 is also disposed radially between the first imaginary circle VC1 and the second imaginary circle VC2.

[0050] By arranging the first flux barrier 31 and the second flux barrier 32 in this manner, in a configuration in which the second rotor core 12 is arranged with the magnetic pole positions shifted circumferentially with respect to the first rotor core 11, the first magnet accommodating holes 14 of the second rotor core 12 can be efficiently filled with resin 16 using the first flux barrier 31 and the second flux barrier 32 provided on the first rotor core 11. Furthermore, the first flux barrier 31 and the second flux barrier 32, which enable efficient injection of resin 16 into each of the first magnet accommodating holes 14 of the multiple rotor cores 11, 12, can be arranged at a position suitable for reducing torque ripple.

[0051] FIG. 9 is a graph showing experimental results for explaining the arrangement of the second flux barrier 32. In FIG. 9, the horizontal axis X1 indicates the distance from the outer circumferential surface of the first rotor core 11 to the second flux barrier 32 arranged on the second axis J2. The distance is shown as a percentage of the radius of the first rotor core 11. The vertical axis Y1 indicates torque ripple. The vertical axis Y1 indicates a value normalized by setting the torque ripple value obtained when the second flux barrier 32 was not arranged to 1. The experimental conditions used for normalization when the second flux barrier 32 was not arranged were the same as those when the experimental data shown in FIG. 9 was obtained, except that the second flux barrier 32 was not arranged.

[0052] 9, when the second flux barrier 32 is disposed at a distance that is 2.9% of the radius of the first rotor core 11 from the outer peripheral surface of the first rotor core 11, the torque ripple is almost the same as when the second flux barrier 32 is not disposed. It can be estimated that when the second flux barrier 32 is disposed at a distance that is greater than 2.9% of the radius of the first rotor core 11 from the outer peripheral surface of the first rotor core 11, the torque ripple is reduced.

[0053] 9, it is preferable to place the second flux barrier 32 at a distance of 3.5% or more of the radius of the first rotor core 11 from the outer circumferential surface of the first rotor core 11. This allows the flux barrier 30, which enables efficient injection of the resin 16 into each of the first magnet accommodating holes 14 of the multiple rotor cores 11, 12, to be placed at an appropriate position, thereby reducing torque ripple.

[0054] The multiple flux barriers 30 are preferably arranged on the same circumference centered on the central axis A. With this configuration, the multiple flux barriers 30 are provided at positions that are the same radial distance from the central axis A, so that the rotor 10 can be prevented from becoming unbalanced, and the rotor 10 can be rotated stably.

[0055] (2-2. Second embodiment) Next, a rotor 10A according to a second embodiment will be described. In describing the rotor 10A according to the second embodiment, the configuration and contents that overlap with those of the first embodiment will be omitted unless there is a particular need to explain them.

[0056] The rotor 10A of this embodiment also has a first rotor core 11A and a second rotor core 12A having a skew structure, similar to the first embodiment. FIG. 10 is a plan view showing the configuration of the first rotor core 11A of the rotor 10A according to the second embodiment. FIG. 10 is an enlarged view of a portion of the first rotor core 11A. FIG. 11 is a view showing the relationship between the first rotor core 11A shown in FIG. 10 and the second rotor core 12A arranged below the first rotor core 11A. In FIG. 11, the configuration related to the second rotor core 12A is indicated by dashed lines.

[0057] 10 and 11, in this embodiment, each of the first rotor core 11A and the second rotor core 12A has a pair of first magnets 13aA, 13bA and a pair of first magnet accommodating holes 14aA, 14bA. However, in this embodiment, each of the first rotor core 11A and the second rotor core 12A further has a pair of second magnets 17a, 17b and a pair of second magnet accommodating holes 18a, 18b. This is different from the first embodiment.

[0058] The pair of second magnets 17a, 17b are arranged in a V-shape radially outward and circumferentially between the pair of first magnets 13aA, 13bA. More specifically, the V-shape is a V-shape in which the circumferential spacing becomes wider as it goes radially outward. Each of the pair of second magnets 17a, 17b has a rectangular parallelepiped shape that is rectangular in a plan view from the axial direction. In a plan view from the axial direction, the longitudinal directions of the pair of second magnets 17a, 17b are inclined in opposite directions to each other with respect to the radial direction. The pair of second magnets 17a, 17b have the same shape and size, and are arranged symmetrically with respect to the first axis J1 of the first rotor core 11A in a plan view from the axial direction.

[0059] The pair of second magnets 17a, 17b are permanent magnets having the same magnetic properties, such as sintered magnets or bonded magnets. The pair of second magnets 17a, 17b form magnetic poles together with the pair of first magnets 13aA, 13bA. In each of the first rotor core 11A and the second rotor core 12A, the number of magnetic poles formed by the pair of first magnets 13aA, 13bA and the pair of second magnets 17a, 17b is eight.

[0060] The pair of second magnet accommodating holes 18a, 18b accommodate a pair of second magnets 17a, 17b. Therefore, in the present embodiment as well, the number of pairs of second magnet accommodating holes 18a, 18b in each of first rotor core 11A and second rotor core 12A is eight. The multiple pairs of second magnet accommodating holes 18a, 18b are arranged at equal intervals in the circumferential direction.

[0061] Similar to the pair of second magnets 17a, 17b, the pair of second magnet accommodating holes 18a, 18b are V-shaped with the circumferential spacing increasing radially outward. The pair of second magnet accommodating holes 18a, 18b are symmetrically disposed with respect to the first axis J1 of the first rotor core 11A in a plan view from the axial direction. The pair of second magnet accommodating holes 18a, 18b are through holes that axially penetrate rotor cores 11A, 12A in which the accommodating holes 18a, 18b are provided.

[0062] In this embodiment, each of the pair of second magnet accommodating holes 18a, 18b has a second gap 19 at both ends in the longitudinal direction of the second magnets 17a, 17b accommodated in the corresponding accommodating holes 18a, 18b in a plan view from the axial direction. The second gap 19 functions as a flux barrier.

[0063] In the present embodiment, the first rotor core 11A has a plurality of flux barriers 30A, similar to the first embodiment. The flux barriers 30A are through holes provided separately from the first magnet accommodating holes 14 and the second magnet accommodating holes 18. The plurality of flux barriers 30A have a first flux barrier 31A and a second flux barrier 32A. However, in the present embodiment, the plurality of flux barriers 30A further have a third flux barrier 33 and a fourth flux barrier 34. This point differs from the first embodiment. The shapes and sizes of the third flux barrier 33 and the fourth flux barrier 34 are also not particularly limited.

[0064] 11, in the present embodiment, as in the first embodiment, the first flux barrier 31A and the second flux barrier 32A at least partially overlap in the axial direction with the first magnet accommodating hole 14A of the second rotor core 12A. In detail, the first flux barrier 31A at least partially overlaps in the axial direction with the first magnet accommodating hole 14aA on one side in the circumferential direction of the pair of first magnet accommodating holes 14aA, 14bA of the second rotor core 12A. The second flux barrier 32A at least partially overlaps in the axial direction with the first magnet accommodating hole 14bA on the other side in the circumferential direction of the pair of first magnet accommodating holes 14aA, 14bA of the second rotor core 12A.

[0065] Furthermore, in this embodiment, the third flux barrier 33 and the fourth flux barrier 34 at least partially overlap in the axial direction with the second magnet accommodating hole 18 of the second rotor core 12A. In detail, the third flux barrier 33 at least partially overlaps in the axial direction with the second magnet accommodating hole 18b on the other circumferential side of the pair of second magnet accommodating holes 18a, 18b of the second rotor core 12. The fourth flux barrier 34 at least partially overlaps in the axial direction with the second magnet accommodating hole 18a on one circumferential side of the pair of second magnet accommodating holes 18a, 18b of the second rotor core 12.

[0066] In Fig. 11, black dots indicate the positions where resin 16A is injected. Fig. 12 is a plan view showing a schematic configuration of a portion of first rotor core 11A after injecting resin 16A. In this embodiment, resin 16 is injected similarly into each magnetic pole of rotor 10A in which first rotor core 11A and second rotor core 12A are stacked. In each magnetic pole of first rotor core 11A, resin 16A is injected into each of the pair of first magnet accommodating holes 14aA, 14bA, each of the pair of second magnet accommodating holes 18a, 18b, first flux barrier 31A, second flux barrier 32A, third flux barrier 33, and fourth flux barrier 34. The first flux barrier 31A and the second flux barrier 32A at least partially overlap with the first magnet accommodating hole 14A of the second rotor core 12A in the axial direction, and the third flux barrier 33 and the fourth flux barrier 34 at least partially overlap with the second magnet accommodating hole 18 of the second rotor core 12A in the axial direction. For this reason, by injecting the resin 16A from the first rotor core 11A side, the resin 16A can be filled not only into the first magnet accommodating hole 14A and the second magnet accommodating hole 18 of the first rotor core 11A, but also into the first magnet accommodating hole 14A and the second magnet accommodating hole 18 of the second rotor core 12A.

[0067] That is, the rotor 10A of this embodiment further has a resin 16A filled in the first magnet accommodating hole 14A, the second magnet accommodating hole 18, and the flux barrier 30A. In detail, the rotor 10A has the resin 16A filled in the first magnet accommodating hole 14A, the second magnet accommodating hole 18, the first flux barrier 31A, the second flux barrier 32A, the third flux barrier 33, and the fourth flux barrier 34. The resin 16A is, for example, an epoxy resin.

[0068] With this configuration, in each of the rotor cores 11A and 12A constituting the rotor 10A, the first magnet 13A can be fixed in the first magnet housing hole 14A and the second magnet 17 can be fixed in the second magnet housing hole 18 using the resin 16A. The first rotor core 11A and the second rotor core 12A can be stacked in the axial direction, and the first magnet 13A and the second magnet 17 in each of the rotor cores 11A and 12A can be fixed together using the resin 16A, thereby improving the work efficiency during the manufacture of the rotor 10A. The resin 16A may cover the upper end face of the first magnet 13A in the first magnet housing hole 14A. In the second rotor core 12A, the lower end of the first magnet 13A housed in the first magnet housing hole 14A of the second rotor core 12A does not have to be covered with the resin 16A. On the lower side of the second rotor core 12A, the lower end of the first magnet 13A may be disposed on the same plane as the lower opening edge of the first magnet accommodating hole 14A of the second rotor core 12A. The resin 16A may cover the upper end face of the second magnet 17 in the second magnet accommodating hole 18. The lower end of the second magnet 17 accommodated in the second magnet accommodating hole 18 of the second rotor core 12A does not have to be covered by the resin 16A. On the lower side of the second rotor core 12A, the lower end of the second magnet 17 may be disposed on the same plane as the lower opening edge of the second magnet accommodating hole 18 of the second rotor core 12A.

[0069] 10, the first flux barrier 31A is disposed circumferentially between the first magnet 13aA on one side of the pair of first magnets 13aA, 13bA in the circumferential direction and the second magnet 17a on one side of the pair of second magnets 17a, 17b in the circumferential direction. In other words, the first flux barrier 31A is disposed circumferentially between the first magnet accommodating hole 14aA on one side of the pair of first magnet accommodating holes 14aA, 14bA in the circumferential direction and the second magnet accommodating hole 18a on one side of the pair of second magnet accommodating holes 18a, 18b in the circumferential direction.

[0070] The second flux barrier 32A is disposed on the second axis J2, similar to the first embodiment. The first flux barrier 31A and the second flux barrier 32A are disposed symmetrically with respect to the first axis J1 of the second rotor core 12A, similar to the first embodiment. The first flux barrier 31A and the second flux barrier 32A are disposed circumferentially between the first virtual circle VC1 and the second virtual circle VC2, similar to the first embodiment.

[0071] The third flux barrier 33 is disposed circumferentially between the first magnet 13bA on the other circumferential side of the pair of first magnets 13aA, 13bA and the second magnet 17b on the other circumferential side of the pair of second magnets 17a, 17b. In other words, the third flux barrier 33 is disposed circumferentially between the first magnet accommodating hole 14bA on the other circumferential side of the pair of first magnet accommodating holes 14aA, 14bA and the second magnet accommodating hole 18b on the other circumferential side of the pair of second magnet accommodating holes 18a, 18b.

[0072] The fourth flux barrier 34 is disposed circumferentially between the first axis J1 of the first rotor core 11A and the second magnet 17a on one side in the circumferential direction of the pair of second magnets 17a, 17b. In other words, the fourth flux barrier 34 is disposed circumferentially between the first axis J1 of the first rotor core 11A and the second magnet accommodating hole 18a on one side in the circumferential direction of the pair of second magnet accommodating holes 18a, 18b.

[0073] In this way, the first flux barrier 31A, the second flux barrier 32A, the third flux barrier 33, and the fourth flux barrier are arranged in consideration of the positional relationship between the first axis J1 and the second axis J2, and the positional relationship between the first magnet 13A and the second magnet 17, so that the plurality of flux barriers 30A can be arranged at positions where torque ripple can be reduced. That is, in the rotor 10A having a skew structure, torque ripple can be reduced and manufacturing efficiency can be improved. Note that, when the direction in which the second rotor core 12A is shifted in the circumferential direction with respect to the first rotor core 11A is opposite to that of this embodiment, the circumferential positional relationship in which the various flux barriers are provided may be appropriately reversed between one side and the other side in the circumferential direction from the above description.

[0074] Fig. 13 is a diagram for explaining the detailed arrangement of a plurality of flux barriers 30A of a first rotor core 11A of the second embodiment. Fig. 13 is an enlarged plan view of a first rotor core 11A similar to Fig. 10. As shown in Fig. 13, in a plan view from the axial direction, a virtual circle having a radius from the central axis A to the radially outermost end of a second magnet accommodating hole 18 is defined as a third virtual circle VC3, and a virtual circle having a radius from the central axis A to the radially outermost end of a second magnet 17 is defined as a fourth virtual circle VC4.

[0075] In this case, at least one of the third flux barrier 33 and the fourth flux barrier 34 is preferably disposed radially between the third virtual circle VC3 and the fourth virtual circle VC4. According to this configuration, the third flux barrier 33 and the fourth flux barrier 34, which enable efficient injection of the resin 16A into each of the second magnet accommodating holes 18 of the rotor cores 11A, 12A, are disposed at appropriate positions, thereby reducing torque ripple. In this embodiment, as a more preferred embodiment, both the third flux barrier 33 and the fourth flux barrier 34 are disposed radially between the third virtual circle VC3 and the fourth virtual circle VC4.

[0076] 11, in this embodiment, the third flux barrier 33 and the fourth flux barrier 34 are disposed at positions symmetrical with respect to the first axis J1 of the second rotor core 12A. By disposing the third flux barrier 33 and the fourth flux barrier 34 in this manner, in a configuration in which the second rotor core 12A is disposed with the magnetic pole positions shifted in the circumferential direction with respect to the first rotor core 11A, the resin 16A can be efficiently filled into the second magnet accommodating holes 18 of the second rotor core 12 using the third flux barrier 33 and the fourth flux barrier 34 provided in the first rotor core 11A. In addition, the third flux barrier 33 and the fourth flux barrier 34, which enable efficient injection of the resin 16A into each of the second magnet accommodating holes 18 of the multiple rotor cores 11A and 12A, can be disposed at positions suitable for reducing torque ripple.

[0077] FIG. 14 is a graph showing experimental results for explaining the arrangement of the third flux barrier 33. In FIG. 14, the horizontal axis X2 indicates the distance of the third flux barrier 33 from the outer peripheral surface of the first rotor core 11A. The distance is shown as a percentage of the radius of the first rotor core 11A. The vertical axis Y2 indicates the torque ripple. The vertical axis Y2 indicates a value normalized by setting the torque ripple value obtained when the third flux barrier 33 is not arranged to 1. The experimental conditions used for normalization when the third flux barrier 33 is not arranged are the same as the experimental conditions when the experimental data shown in FIG. 14 is obtained, except that the third flux barrier 33 is not arranged. When the third flux barrier 33 is arranged, the circumferential position of the third flux barrier 33 is the same.

[0078] As shown in FIG. 14, the third flux barrier 33 tends to reduce torque ripple when it is closer to the outer peripheral surface of the first rotor core 11A. However, the closer the third flux barrier 33 is to the outer peripheral surface of the first rotor core 11A, the more difficult it becomes to arrange the third flux barrier 33 on the first rotor core 11A in terms of manufacturing. For this reason, it is preferable to arrange the third flux barrier 33 at a position slightly shifted radially inward from the outer peripheral surface of the first rotor core 11A. Also, when the third flux barrier 33 is arranged at a distance of 7.3% of the radius of the first rotor core 11A from the outer peripheral surface of the first rotor core 11A, the torque ripple becomes almost the same as when the third flux barrier 33 is not arranged.

[0079] For these reasons, it is preferable that the third flux barrier 33 is disposed at a distance of 1.9% to 6.2% of the radius of the first rotor core 11A from the outer circumferential surface of the first rotor core 11A. This allows the third flux barrier 33 to be disposed at an appropriate position to reduce torque ripple.

[0080] The first flux barrier 31A is disposed circumferentially between the pair of first magnets 13aA, 13bA and the pair of second magnets 17a, 17b, similarly to the third flux barrier 33. For this reason, it is preferable that the distance of the first flux barrier 31A from the outer peripheral surface of the first rotor core 11A is the same as that of the third flux barrier 33. That is, it is preferable that the first flux barrier 31A is also disposed at a distance of 1.9% to 6.2% of the radius of the first rotor core 11A from the outer peripheral surface of the first rotor core 11A. This allows the first flux barrier 31A to be disposed at an appropriate position to reduce torque ripple.

[0081] In the present embodiment, as a preferred embodiment, the first flux barrier 31A and the third flux barrier 33 are disposed symmetrically with respect to the first axis J1 of the first rotor core 11A in a plan view from the axial direction. With this configuration, it is possible to prevent the first rotor core 11A from becoming unbalanced, and it is possible to stably rotate the rotor 10A.

[0082] FIG. 15 is a first graph showing experimental results for explaining the arrangement of the fourth flux barrier 34. In FIG. 15, the horizontal axis X3 indicates the angle of the fourth flux barrier 34 with respect to the first axis J1 of the first rotor core 11A. The vertical axis Y3 indicates torque ripple. However, the vertical axis Y3 indicates a value normalized by setting the torque ripple value obtained when the fourth flux barrier 34 is not arranged to 1. The experimental conditions used for normalization when the fourth flux barrier 34 is not arranged are the same as the experimental conditions when the experimental data shown in FIG. 15 was obtained, except that the fourth flux barrier 34 is not arranged. Also, when the fourth flux barrier 34 is arranged, the torque ripple value obtained when the fourth flux barrier 34 is arranged is normalized to 1. 4 The radial positions of the respective axial members are the same.

[0083] 15, if the angle of the fourth flux barrier 34 with respect to the first axis J1 is too small, the torque ripple tends to become high. If the angle of the fourth flux barrier 34 with respect to the first axis J1 is smaller than 1.5°, the torque ripple may become higher than when the fourth flux barrier 34 is not provided. If the angle of the fourth flux barrier 34 with respect to the first axis J1 is too large, the torque ripple tends to become higher. When the angle of the fourth flux barrier 34 with respect to the first axis J1 is 5.5°, the torque ripple is higher than when the fourth flux barrier 34 is not provided.

[0084] FIG. 16 is a second graph showing experimental results for explaining the arrangement of the fourth flux barrier 34. In FIG. 16, the horizontal axis X4 indicates the distance of the fourth flux barrier 34 from the outer peripheral surface of the first rotor core 11A. The distance is shown as a percentage of the radius of the first rotor core 11A. The vertical axis Y4 indicates the torque ripple. The vertical axis Y4 indicates a value normalized by setting the torque ripple value obtained when the fourth flux barrier 34 is not arranged to 1. The experimental conditions used for normalization when the fourth flux barrier 34 is not arranged are the same as the experimental conditions when the experimental data shown in FIG. 16 is obtained, except that the fourth flux barrier 34 is not arranged. When the fourth flux barrier 34 is arranged, the circumferential position of the fourth flux barrier 34 is the same.

[0085] As shown in FIG. 16, the fourth flux barrier 34 tends to reduce torque ripple when it is closer to the outer peripheral surface of the first rotor core 11A. However, similar to the third flux barrier 33, the closer the fourth flux barrier 34 is to the outer peripheral surface of the first rotor core 11A, the more difficult it becomes to arrange the fourth flux barrier 34 in the first rotor core 11A in terms of manufacturing. For this reason, it is preferable to arrange the fourth flux barrier 34 at a position slightly shifted radially inward from the outer peripheral surface of the first rotor core 11A. In addition, if the fourth flux barrier 34 is arranged at a distance from the outer peripheral surface of the first rotor core 11A that exceeds 5.2% of the radius of the first rotor core 11A, it is estimated that the torque ripple will be almost the same as when the fourth flux barrier 34 is not arranged.

[0086] For these reasons, it is preferable that the fourth flux barrier 34 be disposed within a range of 1.5° to 5° from the first axis J1 of the first rotor core 11A and at a distance of 1.9% to 4.5% of the radius of the first rotor core 11A from the outer circumferential surface of the first rotor core 11A. This allows the fourth flux barrier 34 to be disposed at an appropriate position to reduce torque ripple.

[0087] In this embodiment, as a preferred embodiment, the plurality of flux barriers 30A further includes a fifth flux barrier 35 disposed at a position symmetrical to the fourth flux barrier 34 with respect to the first axis J1 of the first rotor core 11A in a plan view from the axial direction (see, for example, FIG. 10, etc.). With such a configuration, it is possible to prevent the first rotor core 11A from becoming unbalanced, and the rotor 10A can be rotated stably. Since the fifth flux barrier 35 is provided for the purpose of adjusting the balance of the first rotor core 11A, it is preferable that the fifth flux barrier 35 is also filled with resin 16A as shown in FIG. 12.

[0088] The fifth flux barrier 35 does not have to be disposed symmetrically to the fourth flux barrier 34. The fifth flux barrier 35 may be disposed on the circumferentially opposite side of the side where the fourth flux barrier 34 is provided with respect to the first axis J1 of the first rotor core 11A, between the first axis J1 and the second magnet 17. In this case, the fifth flux barrier 35 is preferably disposed within a range of 1.5° to 5° from the first axis J1 of the first rotor core 11A, and at a distance of 1.9% to 4.5% of the radius of the first rotor core 11A from the outer peripheral surface of the first rotor core 11A. This allows the fifth flux barrier 35 to be disposed at an appropriate position to reduce torque ripple.

[0089] In this embodiment, similarly to the first embodiment, the multiple flux barriers 30 are preferably arranged on the same circumference centered on the central axis A. With this configuration, the multiple flux barriers 30A are provided at positions that are the same radial distance from the central axis A, so that the rotor 10A can be prevented from becoming unbalanced, and the rotor 10A can be rotated stably.

[0090] Fig. 17 is a diagram for explaining the second rotor core 12A of the rotor 10A of the second embodiment. Fig. 17 is a diagram showing in more detail the configuration of the second rotor core 12A in Fig. 11. As shown in Fig. 17, the second rotor core 12A may also have a flux barrier 30A penetrating in the axial direction.

[0091] In this embodiment, the second rotor core 12A has an unfilled flux barrier 36 that penetrates in the axial direction and is covered by the first rotor core 11A and is not filled with the resin 16A. By allowing such a configuration, the second rotor core 12A can be made to have the same shape as the first rotor core 11A. In other words, the first rotor core 11A and the second rotor core 12A can be manufactured using the same mold, thereby reducing manufacturing costs. In this embodiment, the second rotor core 12A has the same configuration as the first rotor core 11A, except for the configuration in which the positions of the magnetic poles are shifted in the circumferential direction.

[0092] <3. Notes> Various technical features disclosed in this specification may be modified in various ways without departing from the spirit of the technical creation. Furthermore, multiple embodiments and modifications shown in this specification may be combined to the extent possible. [Industrial Applicability]

[0093] The technology disclosed herein can be used in, for example, home appliances, automobiles, ships, aircraft, trains, power-assisted bicycles, wind power generators, and the like. [Explanation of symbols]

[0094] 10, 10A...Rotor 11, 11A: First rotor core 12, 12A...Second rotor core 13, 13A...First magnet 14, 14A...First magnet receiving hole 16, 16A...Resin 17 Second magnet 18 Second magnet housing hole 20. Stator 30, 30A···Flux barrier 31, 31A: First flux barrier 32, 32A...Second flux barrier 33. Third flux barrier 34 Fourth Flux Barrier 35. Fifth Flux Barrier 36 Unfilled flux barrier 100 Rotating electric motor 200 Drive unit 201 Gear unit 300 Mobile 301...Moving operation part A...Center axis J1...1st axis J2...2nd axis VC1: First virtual circle VC2: Second virtual circle VC3: Third virtual circle VC4: Fourth virtual circle

Claims

1. A rotor that rotates about a central axis, The rotor core includes a first rotor core and a second rotor core that are arranged in an axial direction and have magnetic poles that are shifted from each other in a circumferential direction. Each of the first rotor core and the second rotor core is A pair of first magnets that are arranged in a V-shape with a circumferential distance that increases toward the radially outward direction and that constitute the magnetic poles; a pair of first magnet accommodating holes that accommodate the pair of first magnets; having The first rotor core further includes a plurality of flux barriers extending therethrough in an axial direction, the plurality of flux barriers include a first flux barrier and a second flux barrier that at least partially overlap with the first magnet accommodating hole of the second rotor core in the axial direction, In plan view from the axial direction, a virtual line connecting a circumferential midpoint of the pair of first magnets and the central axis is defined as a first axis; a second axis is a virtual line that is adjacent to the first axis in the circumferential direction, magnetically perpendicular to the first axis, and passes through the central axis; the first flux barrier is disposed between the first shaft and the first magnet in a circumferential direction, the second flux barrier is disposed on the second axis; a virtual circle having a radius extending from the central axis to the radially outermost end of the first magnet accommodating hole is defined as a first virtual circle; a virtual circle having a radius from the central axis to the radially outermost end of the first magnet is defined as a second virtual circle; the second flux barrier is disposed radially between the first virtual circle and the second virtual circle, A rotor, wherein the first flux barrier and the second flux barrier are disposed symmetrically with respect to the first axis of the second rotor core.

2. A rotor as described in claim 1, wherein the second flux barrier is positioned at a distance from the outer peripheral surface of the first rotor core that is at least 3.5% of the radius of the first rotor core.

3. A rotor rotating about a central axis, The rotor core includes a first rotor core and a second rotor core that are arranged in an axial direction and have magnetic poles that are shifted from each other in a circumferential direction. Each of the first rotor core and the second rotor core is A pair of first magnets that are arranged in a V-shape with a circumferential distance that increases toward the radially outward direction and that constitute the magnetic poles; a pair of first magnet accommodating holes that accommodate the pair of first magnets; a pair of second magnets arranged in the V-shape radially outwardly and circumferentially between the pair of first magnets, the pair of second magnets constituting the magnetic poles together with the pair of first magnets; a pair of second magnet accommodating holes that accommodate the pair of second magnets; having The first rotor core further includes a plurality of flux barriers extending therethrough in an axial direction, The plurality of flux barriers include a first flux barrier and a second flux barrier at least partially overlapping with the first magnet accommodating hole of the second rotor core in the axial direction; a third flux barrier and a fourth flux barrier at least partially overlapping with the second magnet accommodating hole of the second rotor core in the axial direction; having In plan view from the axial direction, a virtual line connecting a circumferential midpoint of the pair of first magnets and the central axis is defined as a first axis; a second axis is a virtual line that is adjacent to the first axis in the circumferential direction, magnetically perpendicular to the first axis, and passes through the central axis; the first flux barrier is disposed between the first shaft and the first magnet in a circumferential direction, and between a first magnet on one side of the pair of first magnets in the circumferential direction and a second magnet on one side of the pair of second magnets in the circumferential direction, the second flux barrier is disposed on the second axis; the third flux barrier is disposed circumferentially between a first magnet on the other side of the pair of first magnets in the circumferential direction and a second magnet on the other side of the pair of second magnets in the circumferential direction, A rotor, wherein the fourth flux barrier is circumferentially disposed between the first shaft of the first rotor core and a second magnet on one side of the pair of second magnets in the circumferential direction.

4. When viewed in a plane from the axial direction, a virtual circle having a radius extending from the central axis to the radially outermost end of the first magnet accommodating hole is defined as a first virtual circle; a virtual circle having a radius from the central axis to the radially outermost end of the first magnet is defined as a second virtual circle; the second flux barrier is disposed radially between the first virtual circle and the second virtual circle, The rotor according to claim 3 , wherein the first flux barrier and the second flux barrier are disposed at positions symmetrical with respect to the first axis of the second rotor core.

5. In plan view from the axial direction, a virtual circle having a radius from the central axis to the outermost end of the second magnet accommodating hole in the radial direction is defined as a third virtual circle; a virtual circle having a radius extending from the central axis to the radially outermost end of the second magnet is defined as a fourth virtual circle; The rotor according to claim 3 , wherein at least one of the third flux barrier and the fourth flux barrier is disposed radially between a third imaginary circle and a fourth imaginary circle.

6. The rotor according to claim 3 , wherein the third flux barrier is disposed at a distance from an outer circumferential surface of the first rotor core that is equal to or greater than 1.9% and equal to or less than 6.2% of a radius of the first rotor core.

7. The rotor according to claim 3 , wherein the first flux barrier and the third flux barrier are disposed at positions symmetrical with respect to the first axis of the first rotor core when viewed in a plan view in the axial direction.

8. 8. The rotor according to claim 3, wherein the fourth flux barrier is disposed within a range of 1.5° to 5° from the first axis of the first rotor core, and at a distance from the outer circumferential surface of the first rotor core that is 1.9% to 4.5% of a radius of the first rotor core.

9. The rotor according to claim 3 , wherein the third flux barrier and the fourth flux barrier are disposed at positions symmetrical with respect to the first axis of the second rotor core when viewed in a plan view in the axial direction.

10. 10. The rotor according to claim 3, wherein the plurality of flux barriers further include a fifth flux barrier arranged in a position symmetrical to the fourth flux barrier with respect to the first axis of the first rotor core when viewed in a plan view from the axial direction.

11. The rotor according to claim 1 , further comprising a resin filled in the first magnet accommodating hole and the flux barrier.

12. The rotor according to claim 3 , further comprising a resin filled in the first magnet accommodating hole, the second magnet accommodating hole, and the flux barrier.

13. The rotor according to claim 11 or 12, wherein the second rotor core has an unfilled flux barrier that penetrates the second rotor core in the axial direction, is covered by the first rotor core, and is unfilled with the resin.

14. The rotor according to claim 1 , wherein the plurality of flux barriers are arranged on the same circumference about a central axis.

15. A rotor according to any one of claims 1 to 14; a stator disposed radially outward of the rotor; A rotating electric motor having the above structure.

16. A rotating electric machine according to claim 15; a gear unit connected to the rotating electric machine; A drive unit having the same.

17. A drive device according to claim 16; A moving operation unit connected to the driving device and capable of moving itself; A moving object having the above configuration.

Images