Rotor structure of rotary electric machine

Abstract

To suppress the impact on rods due to the thermal deformation of a rotor core.SOLUTION: The rotor structure of a drive motor 2 comprises: a plurality of reinforcement rods 73 arranged in a row in the circumferential direction penetrating a rotor core 11 in the axial or radial direction; and a first oil passage 81 formed in each of the reinforcement rods 73 and extending in the axial direction of the reinforcement rods 73, for circulating oil to the outside of the rotor 10.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The technology disclosed herein belongs to the technical field related to the rotor structure of a rotating electrical machine.

Background Art

[0002] Conventionally, in order to reinforce the rotor, a structure has been known in which a plurality of rods penetrating the rotor core are provided.

[0003] For example, in Patent Document 1, there is known a rotor structure including a rotor core, a conductor bar (rod) penetrating the rotor core in the axial direction of the central axis of the rotor core, an annular end ring provided at an end of the rotor core and connected to the conductor bar protruding from the end, and an annular first reinforcing member provided between the rotor core and the end ring and in contact with the end ring, and an insertion hole into which the conductor bar protruding from the end is inserted is formed in the first reinforcing member.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, when the rotor core generates heat, the rotor core undergoes thermal deformation. When the rotor core undergoes thermal deformation, the rod also deforms. When the rod deforms, there is a possibility that the reinforcing effect by the rod cannot be expected.

[0006] The technology disclosed herein has been made in view of such a point, and its object is to suppress the influence on the rod due to the thermal deformation of the rotor core.

Means for Solving the Problems

[0007] To solve the above problems, a first aspect of the technology disclosed herein is directed to a rotor structure of a rotating electrical machine including a rotor having a rotor core fixed to a shaft and a stator having a stator core disposed with a gap from the rotor core, the rotor core being penetrated in an axial direction or a radial direction, and a plurality of rods arranged side by side in a circumferential direction, and first oil passages respectively formed in the rods, extending in an axial direction of the rods, and circulating oil with the outside of the rotor.

[0008] In the first aspect, the rotor core can be cooled by the oil passing through the first oil passage. In particular, since the peripheral portion of the rod in the rotor core can be effectively cooled, deformation of the rod due to thermal deformation of the rotor core can be suppressed.

[0009] A second aspect of the technology disclosed herein is, in the first aspect, the rotor core has a plurality of hole portions provided at intervals in the circumferential direction, the rods are respectively arranged so as to penetrate the hole portions with a gap from an inner peripheral surface of the hole portions, and the rods have a plurality of communication holes communicating the first oil passage and the hole portions.

[0010] In the second aspect, by allowing the oil to flow out into the holes, the cooling area can be made as wide as possible. Thereby, the rotor core can be effectively cooled, and deformation of the rod due to thermal deformation of the rotor core can be suppressed.

[0011] A third aspect of the technology disclosed herein is that, in the first or second aspect, the rotating electrical machine is a radial gap motor in which the rotor and the stator are arranged with a gap in the radial direction. The rotor has a pair of end plates provided on one end side and the other end side in the axial direction of the rotor core, respectively. The shaft has a second oil passage extending axially through the shaft. The rod penetrates the rotor core in the axial direction and is connected to the end plate. A first guide path for guiding oil from the second oil passage to the first oil passage is provided between the end plate on the one end side and the rotor core. A second guide path for guiding oil from the first oil passage to the second oil passage is provided between the end plate on the other end side and the rotor core.

[0012] In the third aspect, a second oil passage is formed in the shaft, and by allowing oil to flow from the second oil passage to the first oil passage, oil can be easily supplied to the first oil passage in each rod. Thereby, the rotor core can be effectively cooled.

[0013] A fourth aspect of the technology disclosed herein is that, in the third aspect, the rotor core has a plurality of holes provided at intervals in the circumferential direction and penetrating the rotor core in the axial direction. The rods are respectively arranged to penetrate the holes with a gap between the rods and the inner circumferential surface of the holes. The rods have a plurality of communication holes for communicating the first oil passage and the holes.

[0014] In the fourth aspect, since the holes penetrate the rotor core, the rod and the rotor core can be separated. Thereby, even if the rotor core is thermally deformed, its thermal deformation can be made less likely to affect the rod.

[0015] The fifth aspect of the technology disclosed herein is that, in the first or second aspect, the rotating electrical machine is an axial-gap motor in which the rotor and the stator are arranged with a gap in the axial direction, the rotor has an inner wall portion provided between the rotor core and the shaft, and an outer wall portion covering the outer peripheral portion of the rotor core, the shaft has a second oil passage extending axially through the shaft, the rod penetrates the rotor core in the radial direction and is connected to the inner wall portion and the outer wall portion respectively, and the first oil passage penetrates the rod so as to communicate the second oil passage with the outside of the rotor.

[0016] In the fifth aspect, a second oil passage is formed in the shaft, and by allowing oil to flow from the second oil passage into the first oil passage, oil can be easily supplied to the first oil passage in each rod. Thereby, the rotor core can be effectively cooled.

[0017] The sixth aspect of the technology disclosed herein is that, in the fifth aspect, the rotor core has a plurality of holes provided at intervals in the circumferential direction and penetrating the rotor core in the radial direction, the rods are respectively arranged so as to penetrate the holes with a gap between the rods and the inner peripheral surface of the holes, and the rods have a plurality of communication holes communicating the first oil passage with the holes.

[0018] In the sixth aspect, since the holes penetrate the rotor core, the rod and the rotor core can be separated from each other. Thereby, even if the rotor core is thermally deformed, the thermal deformation can be made less likely to affect the rod.

Advantages of the Invention

[0019] As described above, according to the technology disclosed herein, by effectively cooling the rotor core, the influence of the thermal deformation of the rotor core on the rod can be suppressed.

Brief Description of the Drawings

[0020]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

BEST MODE FOR CARRYING OUT THE INVENTION

[0021] Hereinafter, exemplary embodiments will be described in detail with reference to the drawings.

[0022] (Embodiment 1) 〈Configuration of Vehicle〉 Figure 1 schematically shows an automobile 1 equipped with a drive motor 2 having a rotor structure according to Embodiment 1. The automobile illustrated here is a hybrid vehicle. As a drive source of the automobile, an engine 3 is mounted together with a drive motor 2 (magnetic force variable motor) to which the disclosed technology is applied. These cooperate to rotationally drive two wheels (drive wheels 4R) that are symmetrically located among the four wheels 4F, 4F, 4R, 4R. Thereby, the automobile 1 moves (runs). This automobile 1 is a hybrid vehicle capable of traveling using electric power. Note that the automobile 1 may be an electric vehicle equipped with only the drive motor 2. The automobile 1 may also be four-wheel drive.

[0023] In the case of this automobile 1, the engine 3 is disposed on the front side of the vehicle body, and the drive wheels 4R are disposed on the rear side of the vehicle body. That is, this automobile 1 is a so-called FR vehicle. In the case of this automobile 1, as a drive source, the engine 3 is the main one rather than the drive motor 2, and the drive motor 2 is used in a form that assists the drive of the engine 3 (so-called mild hybrid). The drive motor 2 is also used not only as a drive source but also as a generator during regeneration.

[0024] The engine 3 is, for example, an internal combustion engine that burns using gasoline as fuel. The engine 3 may be a diesel engine using light oil as fuel. The drive motor 2 is connected to the rear of the engine 3 via a first clutch 5. The drive motor 2 is a permanent magnet synchronous motor driven by three-phase alternating current.

[0025] This drive motor 2 is a magnetic force variable motor as described above. The rotor is provided with a magnetic force fixed magnet 40 and magnetic force variable magnets 51, 52, which will be described later, and is configured to be able to change the magnetic force. In order to improve the motor performance, the structure of the rotor is devised. Details of the drive motor 2 will be described later.

[0026] The drive motor 2 is connected to the battery 7 via the inverter 6. The battery 7 is composed of a plurality of lithium-ion batteries. The rated voltage of the battery 7 is 50 V or less (specifically, 48 V). The battery 7 supplies DC power to the inverter 6. The inverter 6 converts the DC power into three-phase alternating current with different phases and supplies it to the drive motor 2. Thereby, the drive motor 2 rotates.

[0027] Behind the drive motor 2, a transmission 9 is connected via a second clutch 8. The transmission 9 is a multi-stage automatic transmission (so-called AT). The rotational power output by the engine 3 and / or the drive motor 2 is output to the transmission 9 through the second clutch 8. The transmission 9 is connected to the differential gear via a propeller shaft.

[0028] The differential gear is connected to the left and right drive wheels 4R via a pair of drive shafts. When the vehicle 1 is running (under power), the rotational power shifted by the transmission 9 is distributed by the differential gear and transmitted to each drive wheel 4R.

[0029] When the vehicle 1 decelerates (during regeneration), energy consumed by using the drive motor 2 is recovered. Specifically, when the vehicle 1 brakes, the second clutch 8 remains engaged while the first clutch 5 is released. By doing so, the drive motor 2 is rotated by the rotational power of the drive wheels to generate electricity. The electric power is charged to the battery 7 to recover energy.

[0030] <Configuration of Drive Motor> Figure 2 shows a cross-section of the drive motor 2. As shown in Figure 3, the drive motor 2 is a six-pole motor having six magnetic pole portions 12 described later. The drive motor 2 includes a rotor 10, a stator 20, and a shaft 30. The drive motor 2 is a radial gap motor, and the rotor 10 and the stator 20 are arranged with a gap in the radial direction. Note that the number of poles of the drive motor 2 is not particularly limited and may be seven poles or more.

[0031] In the following description, the rotational axis direction or the axial direction represents the direction in which the rotational axis Q extends. The radial direction represents the radial direction centered on the rotational axis Q. The circumferential direction represents the direction around the rotational axis Q. In the radial direction, the side far from the rotational axis Q is referred to as the "outer radial side", and the side close to the rotational axis Q is referred to as the "inner radial side".

[0032] 〔Stator〕 The stator 20 faces the rotor 10 with a gap in the radial direction. The stator 20 has a stator core 21 and a plurality of coils 22.

[0033] The stator core 21 has an annular back yoke 21a and a plurality (nine) of teeth 21b that radially protrude inward in the radial direction from the back yoke 21a. For example, the stator core 21 is a laminated core formed by laminating a plurality of electromagnetic steel sheets with high magnetic permeability in the rotational axis direction.

[0034] The plurality of coils 22 are wound around the plurality of teeth 21b. When the plurality of coils 22 are energized, magnetic flux is generated in the plurality of coils 22. For example, the plurality of coils 22 constitute a three-phase coil group consisting of a U-phase, a V-phase, and a W-phase with different phases of the flowing current. The coils 22 of each phase are arranged in order in the circumferential direction.

[0035] In this example, the magnetic flux generated in the plurality of coils 22 includes a rotational magnetic flux for rotating the rotor 10 and a variable magnetic flux (predetermined magnetic flux) for changing the magnetization states of the first magnetically variable magnet 51 and the second magnetically variable magnet 52 described later.

[0036] For example, by supplying an alternating current to a plurality of coils 22, a rotating magnetic flux is generated in the plurality of coils 22. The rotor 10 rotates due to this rotating magnetic flux. Further, during the rotation (or stop) of the rotor 10, a variable magnetic flux is generated in the plurality of coils 22 by supplying a predetermined current (for example, a pulse current larger than the alternating current that generates the rotating magnetic flux) to the plurality of coils 22 for a predetermined time. The magnetization states of the first magnetic force variable magnet 51 and the second magnetic force variable magnet 52, which will be described later, change due to this variable magnetic flux.

[0037] 〔Rotor〕 Next, the rotor 10 will be described with reference to FIGS. 2 and 3. The rotor 10 includes a rotor core 11 and a plurality of magnetic pole portions 12.

[0038] 〔Rotor Core〕 The rotor core 11 is formed in a cylindrical shape. For example, the rotor core 11 is a laminated core in which a plurality of electromagnetic steel sheets with high magnetic permeability are laminated in the axial direction. A shaft hole is provided at the central portion of the rotor core 11. A shaft 30 is inserted and fixed in the shaft hole.

[0039] 〔Magnetic Pole Portion〕 The plurality of magnetic pole portions 12 are provided on the rotor core 11 and are arranged in the circumferential direction. Each of the plurality of magnetic pole portions 12 has a magnetic force fixed magnet 40, a first magnetic force variable magnet 51, a second magnetic force variable magnet 52, a first auxiliary magnet 61, and a second auxiliary magnet 62.

[0040] The magnetic pole portions 12 adjacent to each other in the circumferential direction of the rotor 10 have different magnetic properties. Specifically, the magnetization directions of the magnetic force fixed magnet 40, the first auxiliary magnet 61, and the second auxiliary magnet 62 are opposite to each other.

[0041] 〈Magnetic Force Fixed Magnet〉 The magnetic force fixed magnet 40 is embedded in the rotor core 11. In this example, the magnetic force fixed magnet 40 is housed in a magnetic force fixed magnet hole H40 provided in the rotor core 11. Further, the magnetic force fixed magnet 40 extends in a direction orthogonal to the radial direction (tangential direction). Specifically, the magnetic force fixed magnet 40 has a rectangular cross-sectional shape and its longitudinal direction faces the tangential direction.

[0042] For the magnetic force fixing magnet 40, a magnet such as a neodymium magnet with a high magnetic flux density and a large coercive force is used. Even when a magnetic flux, for example, a magnetic flux generated by a large current (e.g., 750 Arms) that the battery 7 and the inverter 6 can output, is applied to the magnetic force fixing magnet 40, its magnetization state does not substantially change. The coercive force of the magnetic force fixing magnet 40 is higher than the coercive forces of the first magnetically variable magnet 51 and the second magnetically variable magnet 52. These magnetic force fixing magnets 40 may be made of different magnetic materials, but in this rotor 10, the same magnetic material is used.

[0043] 〈Magnetically Variable Magnet〉 The first magnetically variable magnet 51 included in each of the plurality of magnetic pole portions 12 is adjacent to the second magnetically variable magnet 52 included in another magnetic pole portion 12 adjacent to one end side in the circumferential direction of the magnetic pole portion 12 (adjacent in the clockwise direction in FIGS. 2 and 3) with the q-axis therebetween. The q-axis is an imaginary line that passes between two adjacent magnetic pole portions 12 in the circumferential direction and extends in the radial direction.

[0044] Also, in each of the plurality of magnetic pole portions 12, the first magnetically variable magnet 51 and the second magnetically variable magnet 52 are arranged symmetrically with respect to the d-axis. The d-axis is an imaginary line that passes through the center in the circumferential direction of the magnetic force fixing magnet 40 and extends in the radial direction.

[0045] 〈First Magnetically Variable Magnet〉 The first magnetically variable magnet 51 is arranged on one end side in the circumferential direction of the magnetic force fixing magnet 40. The first magnetically variable magnet 51 faces the magnetic force fixing magnet 40 with a gap therebetween in the circumferential direction. The circumferential length between the first magnetically variable magnet 51 and the q-axis is shorter than the circumferential length between the first magnetically variable magnet 51 and the magnetic force fixing magnet 40.

[0046] The first magnetically variable magnet 51 is embedded in the rotor core 11. In this example, the first magnetically variable magnet 51 is housed in a first magnetically variable magnet hole H51 provided in the rotor core 11. Further, the first magnetically variable magnet 51 extends along the q-axis (adjacent q-axes in the circumferential direction). Specifically, the first magnetically variable magnet 51 has a rectangular cross-sectional shape and its longitudinal direction faces a direction parallel to the q-axis.

[0047] 〈Second Magnetically Variable Magnet〉 The second magnetically variable magnet 52 is disposed on the other end side in the circumferential direction of the magnetically fixed magnet 40. The second magnetically variable magnet 52 faces the magnetically fixed magnet 40 with a gap therebetween in the circumferential direction. The circumferential length between the second magnetically variable magnet 52 and the q-axis is shorter than the circumferential length between the second magnetically variable magnet 52 and the magnetically fixed magnet 40.

[0048] The second magnetically variable magnet 52 is embedded in the rotor core 11. In this example, the second magnetically variable magnet 52 is housed in a second magnetically variable magnet hole H52 provided in the rotor core 11. Further, the second magnetically variable magnet 52 extends along the q-axis (adjacent q-axes in the circumferential direction). Specifically, the second magnetically variable magnet 52 has a rectangular cross-sectional shape and its longitudinal direction faces a direction parallel to the q-axis.

[0049] 〈Magnetic Characteristics of Magnetically Variable Magnet〉 For the first magnetically variable magnet 51 and the second magnetically variable magnet 52, magnets such as neodymium magnets, samarium cobalt magnets, and alnico magnets, which have a high magnetic flux density but a small coercive force, are used. Each of the first magnetically variable magnet 51 and the second magnetically variable magnet 52 can change its magnetic force by a magnetic flux generated by a predetermined magnetic flux, for example, a large current (e.g., 750 Arms) that the battery 7 and the inverter 6 can output. The first magnetically variable magnet 51 and the second magnetically variable magnet 52 are hardly magnetized at the magnitude of the current when the drive motor 2 is normally driven. At this time, the first magnetically variable magnet 51 and the second magnetically variable magnet 52 also function as permanent magnets.

[0050] In this example, the easy magnetization direction of each of the first magnetically variable magnet 51 and the second magnetically variable magnet 52 faces the circumferential direction, more specifically, the direction orthogonal to the radial direction (tangential direction). The difficult magnetization direction of the first magnetically variable magnet 51 faces the direction orthogonal to the easy magnetization direction of the first magnetically variable magnet 51 (the radial direction in this example). The difficult magnetization direction of the second magnetically variable magnet 52 faces the direction orthogonal to the easy magnetization direction of the second magnetically variable magnet 52 (the radial direction in this example).

[0051] Also, in this example, each of the first magnetically variable magnet 51 and the second magnetically variable magnet 52 can be switched between a state where the magnetization direction faces the first direction, a state where the magnetization direction faces the second direction, and a zero state where the magnetic force is substantially zero. The first direction is the direction in which the magnetic flux (effective magnetic flux) linking with the teeth 21b increases. The second direction is the direction in which the magnetic flux (effective magnetic flux) linking with the teeth 21b decreases. For example, when the magnetization direction of the magnetically fixed magnet 40 faces outward in the radial direction, the first direction is the direction from the first magnetically variable magnet 51 (or the second magnetically variable magnet 52) toward the magnetically fixed magnet 40, and the second direction is the direction from the magnetically fixed magnet 40 toward the first magnetically variable magnet 51 (or the second magnetically variable magnet 52).

[0052] 〈Auxiliary Magnet〉 In each of the plurality of magnetic pole portions 12, the first auxiliary magnet 61 and the second auxiliary magnet 62 are arranged symmetrically with respect to the d-axis.

[0053] 〈First Auxiliary Magnet〉 The first auxiliary magnet 61 is arranged between the magnetically fixed magnet 40 and the first magnetically variable magnet 51. The circumferential length between the first auxiliary magnet 61 and the magnetically fixed magnet 40 is shorter than the circumferential length between the first auxiliary magnet 61 and the first magnetically variable magnet 51.

[0054] The first auxiliary magnet 61 is embedded in the rotor core 11. In this example, the first auxiliary magnet 61 is accommodated in a first auxiliary magnet hole H61 provided in the rotor core 11. Further, the first auxiliary magnet 61 extends along one circumferential end portion of the magnetic force fixing magnet 40. Specifically, the first auxiliary magnet 61 has a rectangular cross-sectional shape, and the short side direction faces the longitudinal direction of the magnetic force fixing magnet 40.

[0055] The first auxiliary magnet 61 is magnetized in a direction that inhibits the flow of magnetic flux between the radially outer end of the magnetic force fixing magnet 40 and the first magnetically variable magnet 51. Specifically, when the magnetization direction of the magnetic force fixing magnet 40 is a direction toward the radially outer side, the magnetization direction of the first auxiliary magnet 61 is a direction from the first magnetically variable magnet 51 toward the magnetic force fixing magnet 40. When the magnetization direction of the magnetic force fixing magnet 40 is a direction toward the radially inner side, the magnetization direction of the first auxiliary magnet 61 is a direction from the magnetic force fixing magnet 40 toward the first magnetically variable magnet 51.

[0056] 〈Second Auxiliary Magnet〉 The second auxiliary magnet 62 is disposed between the magnetic force fixing magnet 40 and the second magnetically variable magnet 52. The circumferential length between the second auxiliary magnet 62 and the magnetic force fixing magnet 40 is shorter than the circumferential length between the second auxiliary magnet 62 and the second magnetically variable magnet 52.

[0057] The second auxiliary magnet 62 is embedded in the rotor core 11. In this example, the second auxiliary magnet 62 is accommodated in a second auxiliary magnet hole H62 provided in the rotor core 11. Further, the second auxiliary magnet 62 extends along the other circumferential end portion of the magnetic force fixing magnet 40. Specifically, the second auxiliary magnet 62 has a rectangular cross-sectional shape, and the short side direction faces the longitudinal direction of the magnetic force fixing magnet 40.

[0058] The second auxiliary magnet 62 is magnetized in a direction that inhibits the flow of magnetic flux between the radially outer end of the magnetic force fixing magnet 40 and the second magneto-variable magnet 52. Specifically, when the magnetization direction of the magnetic force fixing magnet 40 is in the radially outward direction, the magnetization direction of the second auxiliary magnet 62 is in the direction from the second magneto-variable magnet 52 toward the magnetic force fixing magnet 40. When the magnetization direction of the magnetic force fixing magnet 40 is in the radially inward direction, the magnetization direction of the second auxiliary magnet 62 is in the direction from the magnetic force fixing magnet 40 toward the second magneto-variable magnet 52.

[0059] 〈Hole portion〉 The first hole portions 71 included in each of the plurality of magnetic pole portions 12 are adjacent to second hole portions 72 included in other magnetic pole portions 12 located on one end side in the circumferential direction of the magnetic pole portion 12 (adjacent in the clockwise direction in the examples of FIGS. 3 and 4), with the q-axis interposed therebetween.

[0060] In each of the plurality of magnetic pole portions 12, the first hole portion 71 and the second hole portion 72 are arranged symmetrically with respect to the d-axis. The first hole portion 71 and the second hole portion 72 suppress the magnetic flux from the stator 20 from entering radially inside the first magneto-variable magnet 51 and the second magneto-variable magnet 52, and facilitate the inflow of magnetic flux into the first magneto-variable magnet 51 and the second magneto-variable magnet 52.

[0061] 〈First hole portion〉 The first hole portion 71 is arranged at a position radially inside the magnetic force fixing magnet 40, the first magneto-variable magnet 51, and the first auxiliary magnet 61 on one end side in the circumferential direction of the magnetic pole portion 12. The first hole portion 71 is separated from the radially inner ends of the magnetic force fixing magnet 40 and the first auxiliary magnet 61.

[0062] The first hole portion 71 penetrates the rotor core 11 in the axial direction. Further, the first hole portion 71 extends along the q-axis (adjacent q-axes in the circumferential direction). Specifically, the cross-sectional shape of the first hole portion 71 is formed in a trapezoidal shape. One hypotenuse of the first hole portion 71 faces in a direction parallel to the q-axis, and the other hypotenuse of the first hole portion 71 faces in a direction parallel to the d-axis.

[0063] 〈Second hole portion〉 The second hollow portion 72 is disposed at a position radially inside the magnetic force fixing magnet 40, the second magnetically variable magnet 52, and the second auxiliary magnet 62 on the other end side in the circumferential direction of the magnetic pole portion 12. The second hollow portion 72 is spaced apart from the radially inner ends of the magnetic force fixing magnet 40 and the second auxiliary magnet 62.

[0064] The second hollow portion 72 penetrates the rotor core 11 in the axial direction. Further, the second hollow portion 72 extends along the q-axis (adjacent q-axes in the circumferential direction). Specifically, the cross-sectional shape of the second hollow portion 72 is formed in a trapezoidal shape. One hypotenuse of the second hollow portion 72 faces a direction parallel to the q-axis, and the other hypotenuse of the second hollow portion 72 faces a direction parallel to the d-axis.

[0065] 〔End Plate, Insulating Sheet〕 As shown in FIG. 4, a first end plate 13 is disposed on one end side in the axial direction of the rotor core 11. A second end plate 14 is disposed on the other end side in the axial direction of the rotor core 11. The outer diameters of the first end plate 13 and the second end plate 14 are equal to the outer diameter of the rotor core 11. A shaft 30 is inserted through the centers of the first end plate 13 and the second end plate 14.

[0066] A first insulating sheet 15 is disposed between the first end plate 13 and the rotor core 11. A second insulating sheet 16 is disposed between the second end plate 14 and the rotor core 11. The outer diameters of the first insulating sheet 15 and the second insulating sheet 16 are equal to the outer diameter of the rotor core 11. A shaft 30 is inserted through the centers of the first insulating sheet 15 and the second insulating sheet 16.

[0067] 〔Reinforcing Rod〕 Reinforcing rods 73 are respectively disposed at the positions of the first hollow portion 71 and the second hollow portion 72 in the circumferential direction. The reinforcing rod 73 is a member for improving the strength of the rotor 10. The reinforcing rods 73 are arranged side by side in the circumferential direction.

[0068] As shown in FIG. 5, the reinforcing rod 73 includes a head portion 73a, a shaft portion 73b, and a threaded portion 73c. The head portion 73a is disposed on one end side of the shaft portion 73b, and the threaded portion 73c is formed on the other end side of the shaft portion 73b. The head portion 73a, the shaft portion 73b, and the threaded portion 73c are concentric. The head portion 73a has a larger diameter than the shaft portion 73b.

[0069] The reinforcing rod 73 is disposed so as to penetrate the first hole portion 71 and the second hole portion 72 with a gap between the inner peripheral surface of the first hole portion 71 and the inner peripheral surface of the second hole portion 72. Specifically, the reinforcing rod 73 penetrates the first end plate 13 and the first insulating sheet 15 and enters the first hole portion 71. After passing through the first hole portion 71, the reinforcing rod 73 penetrates the second insulating sheet 16. The threaded portion 73c of the reinforcing rod 73 is connected to the second end plate 14 by screwing. On the other hand, the head portion 73a of the reinforcing rod 73 is located on the one end side in the axial direction of the first end plate 13 without penetrating the first end plate 13. The head portion 73a is received in a recess 13a provided in the first end plate 13. Thereby, the reinforcing rod 73 is connected and fixed to the first end plate 13 and the second end plate 14. In a state where the reinforcing rod 73 is fixed to the first end plate 13 and the second end plate 14, the head portion 73a is flush with the first end plate 13. Although not shown, the reinforcing rod 73 disposed at the position of the second hole portion 72 has the same configuration.

[0070] The reinforcing rod 73 is made of a non-magnetic conductor such as aluminum or copper. When a magnetic flux for changing the magnetization states of the first magnetically variable magnet 51 and the second magnetically variable magnet 52 is input, the reinforcing rod 73 generates an eddy current that generates a repulsive magnetic flux that repels the magnetic flux. Due to the repulsive magnetic flux, it becomes difficult for the magnetic flux to enter through the first hole portion 71 and the second hole portion 72, so that the magnetic flux can be made to flow easily toward the first magnetically variable magnet 51 and the second magnetically variable magnet 52.

[0071] 〔Oil passage〕 The rotor 10 is formed with an oil passage for supplying oil for cooling the rotor 10. As shown in FIG. 4, the oil passage includes a first oil passage 81 formed in the reinforcing rod 73 and a second oil passage 82 formed in the shaft 30. The oil passage also includes a first guide passage 83 for guiding oil from the second oil passage 82 to the first oil passage 81 and a second guide passage 84 for guiding oil from the first oil passage 81 to the second oil passage 82.

[0072] The first oil passage 81 is formed in the shaft portion 73b of the reinforcing rod 73. The first oil passage 81 extends in a first specific direction that is the axial direction of the reinforcing rod 73. The first specific direction is parallel to the axial direction of the shaft 30.

[0073] The shaft portion 73b is provided with a plurality (six in FIGS. 4 and 5) of communication holes 85 that communicate the first oil passage 81 with the first hole portion 71 and the second hole portion 72. The communication holes 85 are arranged side by side in the first specific direction and are arranged to face each other in a second specific direction orthogonal to the first specific direction. Further, the shaft portion 73b has an inflow hole 86 for allowing oil to flow from the first guide passage 83 into the first oil passage 81 and an outflow hole 87 for allowing oil to flow out from the first oil passage 81 to the second guide passage 84. In the circumferential direction of the shaft portion 73b, the inflow hole 86 and the outflow hole 87 are formed at the same position. In the circumferential direction of the shaft portion 73b, the inflow hole 86 and the outflow hole 87 do not necessarily have to be at the same position as the communication holes 85.

[0074] The second oil passage 82 extends in the axial direction of the shaft 30. The flow cross-sectional area of the second oil passage 82 is larger than the flow cross-sectional area of the first oil passage 81. The second oil passage 82 has an upstream passage 82a that communicates with the first guide passage 83 and a downstream passage 82b that communicates with the second guide passage 84. A partition wall 31 is provided between the upstream passage 82a and the downstream passage 82b. Due to the presence of the partition wall 31, the oil in the upstream passage 82a does not directly flow into the downstream passage 82b and always flows into the downstream passage 82b after passing through the first guide passage 83, the first oil passage 81, and the second guide passage 84.

[0075] The first guide path 83 is formed between the rotor core 11 and the first end plate 13, more specifically, between the first insulating sheet 15 and the first end plate 13. The first guide path 83 is formed by forming a groove in a part of the first insulating sheet 15.

[0076] The second guide path 84 is formed between the rotor core 11 and the second end plate 14, more specifically, between the second insulating sheet 16 and the second end plate 14. The second guide path 84 is formed by forming a groove in a part of the second insulating sheet 16.

[0077] 〔Flow of oil〕 Next, the flow of oil in the rotor 10 will be described. Since the flow of oil in the first hole portion 71 is the same as the flow of oil in the second hole portion 72, in the following description, only the flow of oil in the first hole portion 71 will be described in detail. Also, it is assumed that the inside of the first hole portion 71 is filled with oil.

[0078] The oil that has passed through the upstream passage 82a from the outside of the rotor 10 flows into the first guide path 83. The oil in the first guide path 83 passes through the inflow hole 86 and flows into the first oil passage 81. The oil that has flowed into the first oil passage 81 flows out from the communication hole 85 into the first hole portion 71. Due to the oil flowing out into the first hole portion 71, a part of the oil present in the first hole portion 71 flows into the first oil passage 81 through the communication hole 85. The oil that has flowed from the first hole portion 71 into the first oil passage 81 flows into the second guide path 84 through the outflow hole 87. The oil that has flowed into the second guide path 84 flows into the downstream passage 82b and flows out to the outside of the rotor 10. The oil that has flowed out to the outside of the rotor 10 flows back into the second oil passage 82 through a passage (not shown).

[0079] As described above, the oil circulates between the inside and the outside of the rotor 10. From this, it can be said that the first oil passage 81 is a passage for circulating the oil between the outside of the rotor 10.

[0080] By circulating oil between the inside and the outside of the rotor 10, the oil can effectively cool the rotor core 11. If the rotor core 11 is cooled, thermal deformation of the rotor core 11 can be suppressed. Thereby, it is possible to suppress the deformation of the reinforcing rod 73 due to the thermal deformation of the rotor core 11. As a result, the reinforcing effect of the rotor core 11 by the reinforcing rod 73 can be maintained in a high state.

[0081] 〔Effect of Embodiment 1〕 As described above, in the rotor 10 having the rotor structure of Embodiment 1, the first oil passage 81 is provided in the reinforcing rod 73 penetrating the rotor core 11. The rotor core 11 can be cooled by the oil passing through the first oil passage 81. In particular, since the peripheral portion of the reinforcing rod 73 in the rotor core 11 can be effectively cooled, deformation of the reinforcing rod 73 due to thermal deformation of the rotor core 11 can be suppressed.

[0082] Further, in the rotor 10 of the present Embodiment 1, the rotor core 11 has a plurality of first hole portions 71 and second hole portions 72 provided at intervals in the circumferential direction, and the reinforcing rod 73 penetrates the first hole portions 71 and the second hole portions 72 with a gap between the inner peripheral surfaces of the first hole portions 71 and the second hole portions 72, respectively, and the reinforcing rod 73 has a plurality of communication holes 85 that communicate the first oil passage 81 with the first hole portions 71 and the second hole portions 72. By allowing the oil to flow out into the first hole portions 71 and the second hole portions 72, the cooling area can be made as wide as possible. Thereby, the rotor core 11 can be effectively cooled, and deformation of the reinforcing rod 73 due to thermal deformation of the rotor core 11 can be suppressed.

[0083] In particular, in the first embodiment, the first hole portion 71 and the second hole portion 72 penetrate the rotor core 11 in the axial direction. By having the first hole portion 71 and the second hole portion 72 penetrate the rotor core 11, the reinforcing rod 73 and the rotor core 11 can be separated from each other. Thereby, even if the rotor core 11 undergoes thermal deformation, it is possible to make it difficult for the thermal deformation to affect the reinforcing effect by the reinforcing rod 73.

[0084] Also, in the first embodiment, the rotor 10 has a first end plate 13 and a second end plate 14 provided on one end side and the other end side in the axial direction of the rotor core 11, respectively. The shaft 30 has a second oil passage 82 extending in the axial direction within the shaft 30. The reinforcing rod 73 penetrates the rotor core 11 in the axial direction and is connected to the first end plate 13 and the second end plate 14. A first guide passage 83 for guiding oil from the second oil passage 82 to the first oil passage 81 is provided between the first end plate 13 and the rotor core 11. A second guide passage 84 for guiding oil from the first oil passage 81 to the second oil passage 82 is provided between the second end plate 14 and the rotor core 11. In this way, by forming the second oil passage 82 in the shaft 30 and allowing oil to flow from the second oil passage 82 to the first oil passage 81, oil can be easily supplied to the first oil passage 81 in each reinforcing rod 73. Thereby, the rotor core 11 can be effectively cooled.

[0085] (Second Embodiment) Hereinafter, the second embodiment will be described in detail with reference to the drawings. In the following description, the same reference numerals are given to the parts common to the first embodiment, and the detailed description thereof will be omitted.

[0086] Embodiment 2 is different from the foregoing Embodiment 1 in that the drive motor 202 is an axial gap motor in which the rotor 210 and the stator 220 are arranged with a gap in the axial direction. The drive motor 202 is a one-rotor two-stator type motor in which two stators 220 are arranged to face each other in the axial direction with respect to the rotor 210. The rotor 210 and the stator 220 are housed in the housing 290.

[0087] A shaft 230 is inserted through the centers of the rotor 210 and each stator 220. The rotor 210 is fixed to the shaft 230. Each stator 220 is connected to the shaft 230 via a bearing, and the stator 220 does not rotate even if the shaft 230 rotates. In the following description, the rotational axis direction or the axial direction represents the direction in which the rotational axis J extends. The radial direction represents the radial direction centered on the rotational axis J. The circumferential direction represents the direction around the rotational axis J. In the radial direction, the side far from the rotational axis J is referred to as the "radial outer side", and the side close to the rotational axis J is referred to as the "radial inner side". Also, the rotor 210 side in the axial direction is referred to as the "axial inner side", and the side opposite to the rotor 210 in the axial direction is referred to as the "axial outer side".

[0088] 〔Stator〕 As shown in FIG. 6, the stator 220 has a stator core 221 and a plurality of coils 222. The stator core 221 has an annular back yoke 221a and a plurality (here, nine) of teeth 221b that project radially inward from the back yoke 221a. For example, the stator core 221 is a laminated core formed by laminating a plurality of electromagnetic steel sheets having a high magnetic permeability in the radial direction.

[0089] The plurality of coils 222 are wound around the plurality of teeth 221b. When the plurality of coils 222 are energized, magnetic flux is generated in the plurality of coils 222. For example, the plurality of coils 222 constitute a three-phase coil group including a U phase, a V phase, and a W phase in which the phases of the flowing currents are different. The coils 222 of each phase are arranged in order in the circumferential direction.

[0090] Similar to the first embodiment, the magnetic fluxes generated in the plurality of coils 222 include a rotating magnetic flux for rotating each rotor 210 and a variable magnetic flux (predetermined magnetic flux) for changing the magnetization states of the first magnetism variable magnet 251 and the second magnetism variable magnet 252 described later.

[0091] By supplying an alternating current to the plurality of coils 222, a rotating magnetic flux is generated in the plurality of coils 222. Each rotor 210 rotates due to this rotating magnetic flux. Further, during the rotation (or stop) of each rotor 210, a variable magnetic flux is generated in the plurality of coils 222 by supplying a predetermined current (for example, a pulse current larger than the alternating current for generating the rotating magnetic flux) to the plurality of coils 222 for a predetermined time. The magnetization states of the first magnetism variable magnet 251 and the second magnetism variable magnet 252 described later change due to this variable magnetic flux.

[0092] 〔Rotor〕 Next, with reference to FIGS. 7 to 9, the rotor 210 will be described. The rotor 210 includes a rotor core 211, a plurality of magnetic pole portions 212, a plurality of hole portions 271, an outer wall portion 216, an inner wall portion 217, and a plurality of reinforcing rods 273.

[0093] 〔Rotor Core〕 The rotor core 211 is formed in a columnar shape. For example, the rotor core 211 is a laminated core in which a plurality of cylindrical electromagnetic steel sheets having a high magnetic permeability are laminated in the radial direction. A shaft hole H230 (see FIG. 9) through which the shaft 230 is inserted is formed at the center of the rotor core 211.

[0094] 〔Magnetic Pole Portion〕 The plurality of magnetic pole portions 212 are provided on the rotor core 211 and are arranged in the circumferential direction. Each of the plurality of magnetic pole portions 212 has a pair of magnetic force fixed magnets 240, a pair of first magnetism variable magnets 251, and a pair of second magnetism variable magnets 252. As shown in FIG. 8, the pair of magnetic force fixed magnets 240, the pair of first magnetism variable magnets 251, and the pair of second magnetism variable magnets 252 are arranged in a mirror image with respect to a specific plane P passing through the center in the axial direction of the rotor 210 and perpendicular to the axial direction.

[0095] The magnetic pole portions 212 adjacent to each other in the circumferential direction of the rotor 210 have different magnetic properties. Specifically, the magnetization directions of the magnetic force fixing magnets 240 are opposite to each other. Also, in the same magnetic pole portion 212, the magnetic force fixing magnets 240 adjacent to each other in the axial direction have magnetization directions opposite to each other.

[0096] 〈Magnetic force fixing magnet〉 The magnetic force fixing magnet 240 is embedded in the rotor core 211. The magnetic force fixing magnet 240 extends in a direction orthogonal to the axial direction (tangential direction). Specifically, the magnetic force fixing magnet 240 has a rectangular cross-sectional shape, with its longitudinal direction facing the tangential direction and its short-side direction facing the axial direction. The magnetic force fixing magnet 240 is formed in a fan shape when viewed from the axial direction. The circumferential length of the magnetic force fixing magnet 240 is shorter toward the inner side in the radial direction. Since the material of the magnetic force fixing magnet 240 is the same as that in the aforementioned Embodiment 1, detailed description thereof is omitted.

[0097] 〈First magnetically variable magnet〉 The first magnetically variable magnet 251 is disposed on one end side in the circumferential direction of the magnetic force fixing magnet 240. The first magnetically variable magnet 251 faces the magnetic force fixing magnet 240 with a gap therebetween in the circumferential direction.

[0098] The first magnetically variable magnet 251 is embedded in the rotor core 211. The first magnetically variable magnet 251 extends along the axial direction. Specifically, the first magnetically variable magnet 251 has a rectangular cross-sectional shape, with its longitudinal direction facing the axial direction and its short-side direction facing the tangential direction.

[0099] The first magnetically variable magnet 251 is formed in a fan shape when viewed from the axial direction. The circumferential length of the first magnetically variable magnet 251 is shorter toward the inner side in the radial direction. Since the material of the first magnetically variable magnet 251 is the same as that in the aforementioned Embodiment 1, detailed description thereof is omitted.

[0100] 〈Second magnetically variable magnet〉 The second magnetism variable magnet 252 is disposed on the other end side in the circumferential direction of the magnetism fixed magnet 240. The second magnetism variable magnet 252 faces the magnetism fixed magnet 240 with a space therebetween in the circumferential direction.

[0101] The second magnetism variable magnet 252 is embedded in the rotor core 211. The second magnetism variable magnet 252 extends along the axial direction. Specifically, the second magnetism variable magnet 252 has a rectangular cross-sectional shape, with its longitudinal direction facing the axial direction and its short-side direction facing the tangential direction.

[0102] The second magnetism variable magnet 252 is formed in a sector shape when viewed from the axial direction. The circumferential length of the second magnetism variable magnet 252 is shorter toward the inner side in the radial direction. Since the material of the second magnetism variable magnet 252 is the same as that in the foregoing Embodiment 1, detailed description thereof is omitted.

[0103] 〔Hole portion〕 As shown in FIG. 8, the hole portion 271 is provided across two adjacent magnetic pole portions 212. The hole portion 271 is provided from a portion on one end side in the circumferential direction of one magnetic pole portion 212 to a portion on the other end side in the circumferential direction of the other magnetic pole portion 212. The hole portion 271 is provided on the rotor core 211 on one end side in the axial direction with respect to a specific plane P and on the other end side in the axial direction with respect to the specific plane P so as to be symmetric with respect to the specific plane P.

[0104] The hole portion 271 has a T-shaped cross section. The hole portion 271 is disposed inside the magnetism fixed magnet 240 in the axial direction and also inside the first magnetism variable magnet 251 and the second magnetism variable magnet 252 in the axial direction. The hole portion 271 protrudes outward in the axial direction at the positions of the first magnetism variable magnet 251 and the second magnetism variable magnet 252 in the circumferential direction.

[0105] As shown in FIGS. 7 and 9, the hole portion 271 penetrates the rotor core 211 in the radial direction. The hole portion 271 is formed in a sector shape when viewed from the axial direction. The circumferential length of the hole portion 271 is shorter toward the inner side in the radial direction.

[0106] The hollow hole portion 271 and the magnetic force fixing magnet 240 are separated from each other in the axial direction and the circumferential direction. The hollow hole portion 271 and the first magnetically variable magnet 251 and the second magnetically variable magnet 252 are separated from each other in the axial direction.

[0107] 〔Outer wall portion, inner wall portion〕 The outer wall portion 216 is a wall portion that covers the outer peripheral portion of the rotor core 211. The outer wall portion 216 is arranged along the circumferential surface on the radially outer side of the rotor core 211. The outer wall portion 216 is cylindrical. The outer wall portion 216 is arranged concentrically with the rotor core 211. The inner diameter of the outer wall portion 216 is equal to the outer diameter of the rotor core 211 or slightly larger than the outer diameter of the rotor core 211.

[0108] The inner wall portion 217 is arranged between the rotor core 211 and the shaft 230. The inner wall portion 217 is arranged along the shaft hole H230 of the rotor core 211. The inner wall portion 217 is cylindrical. The inner wall portion 217 is arranged concentrically with the rotor core 211. The outer diameter of the inner wall portion 217 is equal to the shaft hole H230 or slightly smaller than the diameter of the shaft hole H230. The inner diameter of the inner wall portion 217 is equal to the diameter of the shaft 230.

[0109] 〔Reinforcing rod〕 A reinforcing rod 273 is disposed in each hollow hole portion 271. The reinforcing rod 273 is disposed in the hollow hole portion 271 on one end side in the axial direction with respect to the specific plane P and in the hollow hole portion 271 on the other end side in the axial direction with respect to the specific plane P, respectively.

[0110] The reinforcing rod 273 includes a head portion 273a, a shaft portion 273b, and a screw portion 273c. The head portion 273a is disposed on one end side of the shaft portion 273b, and the screw portion 273c is formed on the other end side of the shaft portion 273b. The head portion 273a, the shaft portion 273b, and the screw portion 273c are concentric. The head portion 273a has a larger diameter than the shaft portion 273b.

[0111] As shown in FIG. 9, the reinforcing rods 273 are each arranged so as to penetrate the hole portion 271 with a gap left between the inner peripheral surface of the hole portion 271. Specifically, the reinforcing rod penetrates the outer wall portion 216, enters the hole portion 271, and extends in the radial direction with a gap left between the inner peripheral surface of the hole portion 271. The threaded portion 273c of the reinforcing rod 273 is connected to the inner wall portion 217 by screwing. On the other hand, the head portion 273a of the reinforcing rod 273 is not penetrated through the outer wall portion 216 but is accommodated in a recess 216a provided in the outer wall portion 216. The depth of the recess 216a is about the same as the thickness of the head portion 273a. Thereby, the reinforcing rod 273 is connected to the outer wall portion 216 and the inner wall portion 217.

[0112] The reinforcing rod 273 is made of a non-magnetic conductor such as aluminum or copper. When magnetic flux for changing the magnetization states of the first magnetically variable magnet 251 and the second magnetically variable magnet 252 is input, the reinforcing rod 273 generates eddy currents that generate repulsive magnetic fluxes that repel the magnetic flux. Due to the repulsive magnetic flux, it becomes difficult for the magnetic flux to enter through the hole portion 271, so that the magnetic flux can be made to flow easily toward the first magnetically variable magnet 251 and the second magnetically variable magnet 252.

[0113] 〔Oil passage〕 In the rotor 210, an oil passage for supplying oil for cooling the rotor 210 is formed. The oil passage includes a first oil passage 281 formed in the reinforcing rod 273 and a second oil passage 282 formed in the shaft 230.

[0114] The first oil passage 281 is formed to penetrate the head portion 273a, the shaft portion 273b, and the threaded portion 273c of the reinforcing rod 273 in a third specific direction that is the axial direction of the reinforcing rod 273. The third specific direction is a direction orthogonal to the axial direction of the shaft 30.

[0115] The shaft portion 273b is provided with a plurality (six in FIGS. 4 and 5) of communication holes 285 that communicate the first oil passage 81 with the hole portion 271. The communication holes 285 are arranged side by side in a third specific direction and are arranged to face each other in a fourth specific direction orthogonal to the third specific direction.

[0116] The second oil passage 282 extends in the axial direction of the shaft 230. The flow cross-sectional area of the second oil passage 282 is larger than the flow cross-sectional area of the first oil passage 281. In the axial direction, the second oil passage 82 does not pass through the entire rotor 210 and is blocked midway.

[0117] The inner wall portion 217 has an inflow hole 284 that communicates the first oil passage 281 with the second oil passage 282 at the position of the first oil passage 281. Thereby, the second oil passage 282 and the outside of the rotor 210 communicate with each other through the first oil passage 281.

[0118] 〔Flow of oil〕 Next, the flow of oil in the rotor 210 will be described. It is assumed that the inside of the hole portion 271 is filled with oil.

[0119] The oil that has passed through the second oil passage 282 from the outside of the rotor 210 flows into the first oil passage 281 through the inflow hole 284. The oil that has flowed into the first oil passage 281 flows out from the communication hole 285 into the hole portion 271. When oil flows out into the hole portion 271, a part of the oil present in the hole portion 271 flows into the first oil passage 281 through the communication hole 285. The oil that has flowed into the first oil passage 281 from the hole portion 271 flows out from the end on the head portion 273a side to the outside of the rotor 210. The oil that has flowed out of the rotor 210 is received by the housing 290 and then drained through the drain oil passage. The drained oil flows back into the second oil passage 282 through a passage (not shown).

[0120] In this way, oil circulates between the inside and the outside of the rotor 210. From this, it can be said that the first oil passage 281 is a passage for circulating oil between the outside of the rotor 210.

[0121] By circulating oil between the inside and the outside of the rotor 210, the oil can effectively cool the rotor core 211. Thereby, it is possible to suppress the deformation of the reinforcing rod 273 due to the thermal deformation of the rotor core 211. As a result, the reinforcing effect of the rotor core 211 by the reinforcing rod 273 can be maintained in a high state.

[0122] 〔Effects of Embodiment 2〕 As described above, in Embodiment 2, the drive motor 202 is an axial gap type motor. The rotor 210 of the drive motor 202 has an inner wall portion 217 provided between the rotor core 211 and the shaft 230, and an outer wall portion 216 covering the outer peripheral portion of the rotor core 211. The shaft 230 has a second oil passage 282 extending axially in the shaft 230. The reinforcing rod 273 penetrates the rotor core 211 in the radial direction and is connected to the inner wall portion 217 and the outer wall portion 216, respectively. The first oil passage 281 penetrates the reinforcing rod 273 so as to communicate the second oil passage 282 with the outside of the rotor 210. In this way, by forming the second oil passage 282 in the shaft 230 and allowing oil to flow from the second oil passage 282 into the first oil passage 281, oil can be easily supplied to the first oil passage 281 in each reinforcing rod 273. Thereby, the rotor core 211 can be effectively cooled.

[0123] Further, in the rotor 210 of the second embodiment, the rotor core 211 has a plurality of hole portions 271 that are provided at intervals in the circumferential direction and penetrate the rotor core 211 in the radial direction. Thereby, since the hole portion 271 penetrates the rotor core 211, the reinforcing rod 273 and the rotor core 211 can be separated from each other. Thereby, even if the rotor core 211 is thermally deformed, it is possible to make it difficult for the thermal deformation to affect the reinforcing effect by the reinforcing rod 273.

[0124] (Other Embodiments) The technology disclosed herein is not limited to the above-described embodiments, and substitution is possible without departing from the gist of the claims.

[0125] In the first and second embodiments, the vehicle 1 is a hybrid vehicle having the engine 3. However, the vehicle 1 is not limited thereto, and may be an electric vehicle having only the drive motors 2 and 202 as drive sources.

[0126] In the first and second embodiments, a gap was formed between the rotor cores 11 and 211 and the reinforcing rods 73 and 273 by the hole portions 71, 72, and 271. However, the rotor cores 11 and 211 and the reinforcing rods 73 and 273 may be in close contact with each other. In this case, the reinforcing rods 73 and 273 may be provided at portions other than the hole portions 71, 72, and 271, or the hole portions 71, 72, and 271 may be omitted.

[0127] In the second embodiment, the hole portions 271 are provided separately on one axial end side with respect to the specific plane P and the other axial end side with respect to the specific plane P. However, the hole portions are not limited thereto, and may be integrated like the hole portion 371 shown in FIG. 10. In this case, the cross section of the hole portion 371 is in a cross shape. Further, since the number of the hole portions 371 decreases, the number of the reinforcing rods 373 arranged in the hole portion 371 also decreases. The reinforcing rod 373 is arranged at the intersection portion in the hole portion 371.

[0128] The foregoing embodiments are merely illustrative and should not be construed as limiting the scope of the present disclosure. The scope of the present disclosure is defined by the claims, and all modifications and changes belonging to the equivalent scope of the claims are within the scope of the present disclosure.

Industrial Applicability

[0129] The technology disclosed herein is useful as a rotor structure of a rotating electrical machine.

Explanation of Signs

[0130] 10 Rotor 11 Rotor Core 14 First End Plate 15 Second End Plate 20 Stator 21 Stator Core 40 Magnetically Fixed Magnet 51 First Magnetically Variable Magnet 52 Second Magnetically Variable Magnet 71 First Hole Portion 72 Second Hole Portion 73 Reinforcing Rod 81 First Oil Passage 82 Second Oil Passage 83 First Guide Path 84 Second Guide Path 85 Communication Hole 210 Rotor 211 Rotor Core 212 Pole Portion 216 Outer Wall Portion 217 Inner Wall Portion 220 Stator 240 Magnetically Fixed Magnet 251 First Magnetically Variable Magnet 252 Second Magnetically Variable Magnet 271 Hole Portion 273 Reinforcing Rod 281 First Oil Passage 282 Second Oil Passage 285 Communication Path

Claims

1. A rotor structure of a rotating electrical machine including a rotor having a rotor core fixed to a shaft, and a stator having a stator core disposed with a gap from the rotor core, wherein a plurality of rods penetrating the rotor core in an axial direction or a radial direction and arranged side by side in a circumferential direction; and first oil passages respectively formed in the rods, extending in an axial direction of the rods, and circulating oil with the outside of the rotor, are provided. A rotor structure of a rotating electrical machine is characterized by comprising the above.

2. In the rotor structure of the rotating electrical machine according to Claim 1, the rotor core has a plurality of hole portions provided at intervals in the circumferential direction, the rods are respectively arranged so as to penetrate the hole portions with a gap from an inner circumferential surface of the hole portions, and the rods have a plurality of communication holes communicating the first oil passages with the hole portions. A rotor structure of a rotating electrical machine is characterized by comprising the above.

3. In the rotor structure of the rotating electrical machine according to Claim 1 or 2, the rotating electrical machine is a radial gap motor in which the rotor and the stator are arranged with a gap in the radial direction, the rotor has a pair of end plates respectively provided on one end side and the other end side in the axial direction of the rotor core, the shaft has a second oil passage extending in an axial direction inside the shaft, the rods penetrate the rotor core in the axial direction and are connected to the end plates, a first guide path for guiding oil from the second oil passage to the first oil passage is provided between the end plate on the one end side and the rotor core, and a second guide path for guiding oil from the first oil passage to the second oil passage is provided between the end plate on the other end side and the rotor core. A rotor structure of a rotating electrical machine is characterized by comprising the above.

4. In the rotor structure of the rotating electrical machine according to Claim 3, the rotor core has a plurality of hole portions provided at intervals in the circumferential direction and penetrating the rotor core in the axial direction, the rods are respectively arranged so as to penetrate the hole portions with a gap from an inner circumferential surface of the hole portions, and the rods have a plurality of communication holes communicating the first oil passages with the hole portions. A rotor structure of a rotating electrical machine is characterized by comprising the above.

5. In the rotor structure of the rotating electrical machine according to Claim 1 or 2 The rotating electrical machine is an axial-gap motor in which the rotor and the stator are arranged with a gap therebetween in the axial direction. The rotor includes: an inner wall portion provided between the rotor core and the shaft; an outer wall portion covering the outer peripheral portion of the rotor core; and has The shaft has a second oil passage extending axially through the shaft. The rod penetrates the rotor core in the radial direction and is connected to the inner wall portion and the outer wall portion, respectively. The first oil passage penetrates the rod so as to communicate the second oil passage with the outside of the rotor. A rotor structure of a rotating electrical machine, characterized by this. **Claim 6** In the rotor structure of the rotating electrical machine according to claim 5, the rotor core has a plurality of hole portions provided at intervals in the circumferential direction and penetrating the rotor core in the radial direction, the rods are respectively arranged so as to penetrate the hole portions with a gap therebetween and the inner peripheral surface of the hole portions, The rod has a plurality of communication holes for communicating the first oil passage with the hole portions. A rotor structure of a rotating electrical machine, characterized by this.

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