Pole piece unit and magnetic-geared electric machine

Abstract

To provide a magnetic pole piece unit with improved strength and a magnetically geared electric machine.SOLUTION: A magnetic pole piece unit includes an annular unit, an inner cover disposed on an inner peripheral surface of the annular unit, an inner plate disposed on the inner circumferential surface of the inner cover, and disposed so as to overlap at least a connecting portion in an axial direction, an outer cover disposed on an outer peripheral surface of the annular unit, an outer plate disposed on the outer peripheral surface of the outer cover, and disposed so as to at least partially overlap the inner plate in the axial direction, and a fastening member including shaft portion arranged to penetrate the outer plate, the outer cover, the connecting portion of the annular unit, the inner cover, and the inner plate in a radial direction of the annular unit.SELECTED DRAWING: Figure 4A

Description

[Technical Field]

[0001] The present disclosure relates to a pole piece unit and a magnetically geared electric machine. [Background technology]

[0002] The magnetic-geared electric machine disclosed in Patent Document 1 includes a plurality of first magnets arranged in a circumferential direction, and a second magnet arranged in a circumferential direction on the outer circumferential side of the plurality of first magnets. A pole piece unit, which is a component of the magnetic-geared electric machine, is provided between the plurality of first magnets and the plurality of second magnets. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] U.S. Patent No. 9,425,655 Summary of the Invention [Problem to be solved by the invention]

[0004] When a magnetic-geared electric machine is in operation, a radial electromagnetic force acts on the pole piece unit, and a design that improves the strength of the pole piece unit is desired to prevent the pole pieces from coming off.

[0005] It is an object of the present disclosure to provide a pole piece unit and a magnetic-geared electric machine with improved strength. [Means for solving the problem]

[0006] A pole piece unit according to one embodiment of the present disclosure comprises: An annular unit extending circumferentially about an axis, a plurality of circumferentially spaced pole pieces; a plurality of non-magnetic bodies arranged at intervals in the circumferential direction, the non-magnetic bodies alternating with the plurality of magnetic pole pieces; and an annular unit including a connecting portion connected to an end of each of the magnetic pole pieces and an end of each of the non-magnetic bodies on one axial side of the axis; an inner cover disposed on an inner circumferential surface of the annular unit; an inner plate disposed on an inner circumferential surface of the inner cover so as to overlap at least the connecting portion in the axial direction; an outer cover disposed on an outer peripheral surface of the annular unit; an outer plate disposed on an outer peripheral surface of the outer cover so as to overlap at least a portion of the inner plate in the axial direction; a fastening member including a shaft portion disposed to penetrate the outer plate, the outer cover, the connecting portion, the inner cover, and the inner plate in a radial direction of the annular unit; Equipped with.

[0007] A pole piece unit according to one embodiment of the present disclosure comprises: An annular unit extending circumferentially about an axis, a plurality of circumferentially spaced pole pieces; a plurality of non-magnetic bodies arranged at intervals in the circumferential direction, the non-magnetic bodies alternating with the plurality of magnetic pole pieces; and an annular unit including a connecting portion connected to an end of each of the magnetic pole pieces and an end of each of the non-magnetic bodies on one axial side of the axis; an inner plate disposed on an inner peripheral surface of the annular unit, the inner plate extending from the inner peripheral surface of the connecting portion to the inner peripheral surface of the pole piece and the inner peripheral surface of the non-magnetic body; an outer plate disposed on an outer peripheral surface of the annular unit, the outer plate extending from an outer peripheral surface of the connecting portion to an outer peripheral surface of the pole piece and an outer peripheral surface of the non-magnetic body; a fastening member including a shaft portion disposed to penetrate the outer plate, the connecting portion, and the inner plate in a radial direction of the annular unit; Equipped with.

[0008] According to one embodiment of the present disclosure, a magnetic-geared electric machine includes: The pole piece unit; a plurality of first magnets arranged in the circumferential direction on the outer or inner side of the annular unit, and a first yoke unit supporting the plurality of first magnets; a plurality of second magnets arranged in the circumferential direction on the inside or outside of the annular unit, and a second yoke unit supporting the plurality of second magnets; Equipped with. [Effects of the Invention]

[0009] According to the present disclosure, a pole piece unit and a magnetic-geared electric machine having improved strength can be provided. [Brief explanation of the drawings]

[0010] [Figure 1A] 1 is a schematic diagram of a magnetic-geared electric machine (magnetic-geared generator) according to one embodiment. [Figure 1B] 1 is a schematic diagram of a magnetic-geared electric machine (magnetic-geared generator) according to another embodiment. [Figure 1C] 1 is a schematic diagram of a magnetic-geared electric machine (magnetic-geared motor) according to one embodiment. [Figure 1D] FIG. 1 is a schematic diagram of a magnetic-geared electric machine (magnetic-geared motor) according to another embodiment. [Figure 2A] 1 is a schematic diagram illustrating a first internal structure of a magnetic-geared electric machine according to one embodiment. [Figure 2B] FIG. 2 is a schematic diagram illustrating a second internal structure of a magnetic-geared electric machine according to an embodiment. [Figure 3] FIG. 2 is a schematic diagram of a pole piece unit according to one embodiment. [Figure 4A] FIG. 2 is a conceptual exploded view (first example) of a pole piece unit according to the first embodiment. [Figure 4B] FIG. 4 is a conceptual exploded view (second example) of a pole piece unit according to the first embodiment. [Figure 4C] 10 is a schematic diagram of a first internal structure to which a pole piece unit according to a second example is applied; FIG. [Figure 5A]FIG. 2 is a conceptual exploded view of a pole piece unit according to the first embodiment. [Figure 5B] FIG. 10 is a schematic view showing an annular portion of a pole piece unit according to a second embodiment. [Figure 5C] FIG. 10 is a schematic view of a first internal structure to which a pole piece unit according to a second embodiment is applied. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, several embodiments of the present disclosure will be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of components described as embodiments or shown in the drawings are merely illustrative examples and are not intended to limit the scope of the present disclosure.

[0012] <1. Overview of Magnetic-Geared Electric Machine 1> 1A to 1D are schematic diagrams of a magnetic-geared electric machine 1 according to some embodiments of the present disclosure. In the following description, an "axial direction" is a direction parallel to the rotation axis (first rotation axis A1 or second rotation axis A2) of the magnetic-geared electric machine 1, a "radial direction" is a direction perpendicular to the rotation axis of the magnetic-geared electric machine 1, and a "circumferential direction" is a circumferential direction based on the rotation axis of the magnetic-geared electric machine 1.

[0013] Each of the magnetic-geared electric machines 1 illustrated in FIGS. 1A to 1D includes, in order from one radial side, a first yoke unit 10, a second yoke unit 20, and a pole piece unit 30. All three units extend in the axial direction. The first yoke unit 10 includes a plurality of first magnets 19 arranged in the circumferential direction and a first yoke 15 supporting the plurality of first magnets 19. The second yoke unit 20 includes a plurality of second magnets 29 arranged in the circumferential direction and a second yoke 25 supporting the plurality of second magnets 29. The pole piece unit 30 includes a plurality of pole pieces 50 arranged at intervals in the circumferential direction, and the plurality of pole pieces 50 face the plurality of first magnets 19 and the plurality of second magnets 29, respectively, with gaps G1 and G2 (see, for example, FIG. 2A ) between the first yoke unit 10 and the second yoke unit 20. Each pole piece 50 has a structure in which a plurality of electromagnetic steel plates are stacked in the axial direction. One of the first yoke unit 10, the second yoke unit 20, and the pole piece unit 30 functions as a stator, and the remaining two function as rotors.

[0014] 1A to 1D, the second yoke unit 20 is disposed on the outer circumferential side of the first yoke unit 10, i.e., the magnetic-geared electric machine 1 includes, in order from the inside (inner circumferential side) in the radial direction, the first yoke unit 10, the pole piece unit 30, and the second yoke unit 20. In another example, the second yoke unit 20 may be disposed on the inner circumferential side of the first yoke unit 10, i.e., the magnetic-geared electric machine 1 may include, in order from the outside (outer circumferential side) in the radial direction (see FIG. 2B).

[0015] The magnetic-geared electric machines 1A, 1B(1) illustrated in FIGS. 1A and 1B are magnetic-geared generators 2A, 2B(2) configured to generate electricity when driven by input from a prime mover 9. The magnetic-geared generator 2 is configured to supply the generated electric power P to a power supply destination 4, which may be, for example, an electric power system. The magnetic-geared electric machines 1C, 1D(1) illustrated in FIGS. 1C and 1D are magnetic-geared motors 3A, 3B(3) configured to receive a supply of electric power P from a power supply source 6, which may be, for example, an electric power system, to drive a rotating machine 8.

[0016] <1-1. Magnetic-geared generator 2> The magnetic-geared generator 2A(2) illustrated in FIG. 1A includes a housing 98 that may be mounted on a base 101. In the example illustrated in the figure, a second yoke unit 20 supported by the housing 98 is provided with a coil 99 as a stator winding that can be electrically connected to the power supply destination 4. That is, in the example illustrated in the figure, the second yoke unit 20 functions as a stator. The housing 98 rotatably supports, via bearings, a first rotating shaft A1 that serves as an input shaft connected to the prime mover 9. Both axial ends of the pole piece unit 30 are respectively connected to a pair of end plates 97. One end plate 97 is connected to the first rotating shaft A1, and the other end plate 97 is connected via bearings to a second rotating shaft A2 that is disposed coaxially with the first rotating shaft A1. Therefore, the pole piece unit 30 illustrated in the figure functions as a rotor that rotates together with the first rotating shaft A1. In this example, the second rotating shaft A2 supports the first yoke unit 10 that is disposed between the pair of end plates 97. Therefore, the first yoke unit 10 illustrated in the figure functions as a rotor that rotates together with the second rotation shaft A2. The second rotation shaft A2 is rotatably supported by the housing 98 via a bearing.

[0017] The magnetic-geared generator 2A converts mechanical input from the prime mover 9 into electric power P by utilizing the harmonic magnetic gear principle and electromagnetic induction. As a more specific example, when the first rotating shaft A1 rotates together with the pole piece unit 30 as the prime mover 9 is driven, the multiple pole pieces 50 move circumferentially relative to the multiple first magnets 19 and the multiple second magnets 29. This modulates the magnetic flux between the first yoke unit 10 and the second yoke unit 20, and the first magnet 19 receives a magnetic force from the modulated magnetic field, causing the first yoke unit 10 to rotate. Electromagnetic induction occurring as the pole piece unit 30 and the first yoke unit 10 rotate generates a current in the coil 99, allowing the magnetic-geared generator 2A to generate electricity. The ratio of the rotation speed of the first yoke unit 10 to the pole piece unit 30 is expressed as the ratio of the number of pole pairs NH of the first magnet 19 to the number of magnetic poles NL of the pole piece 50 (=NL / NH). In this example, NL / NH is greater than 1, so the first yoke unit 10 functions as a high-speed rotor, and the pole piece unit 30 functions as a low-speed rotor. Note that the number of poles NL of the pole piece 50 is less than the number of poles NS of the second magnet 29.

[0018] In the magnetic-geared generator 2A illustrated in FIG. 1A, the second rotating shaft A2 may function as the input shaft instead of the first rotating shaft A1. Although detailed illustration is omitted, in this case, the prime mover 9 is coupled to the second rotating shaft A2. When the first yoke unit 10 rotates together with the second rotating shaft A2 due to the driving of the prime mover 9, the multiple first magnets 19 move relative to the multiple pole pieces 50 and the multiple second magnets 29, and the pole pieces 50 modulate the magnetic flux between the first yoke unit 10 and the second yoke unit 20. Therefore, the magnetic force resulting from the modulation of the magnetic field causes the pole pieces 50 to rotate together with the first rotating shaft A1. As a result, electromagnetic induction occurs as the first yoke unit 10 and the pole piece unit 30 rotate, generating a current in the coil 99, enabling the magnetic-geared generator 2A to generate electricity. In this case as well, a configuration in which NL / NH is greater than 1 is adopted, so that the first yoke unit 10 functions as a high-speed rotor, and the pole piece unit 30 functions as a low-speed rotor.

[0019] 1A may be a single rotating shaft. Although detailed illustration is omitted, in this case, a single rotating shaft connected to the prime mover 9 is rotatably supported by a housing 98 and is rotatably connected to the first yoke unit 10. A pair of end plates 97 are fixed to the outer periphery of the rotating shaft. In this configuration, when the pole piece unit 30 is rotated by being driven by the prime mover 9, the first yoke unit 10 rotates and a current is generated in the coil 99.

[0020] In the magnetic-geared generator 2B(2) illustrated in FIG. 1B, the pole piece unit 30 functions as a stator, and the first yoke unit 10 and the second yoke unit 20 function as a rotor. The magnetic-geared generator 2B includes a housing 96 that may be mounted on a base 101, and the housing 96 supports the pole piece unit 30. A plurality of pole pieces 50 are arranged at intervals in the circumferential direction, and each has a coil 99 as a stator winding that can be electrically connected to a power supply destination 4. The housing 96 rotatably supports a second rotating shaft A2 via a bearing. The second rotating shaft A2, which functions as an input shaft in the illustrated example, supports the first yoke unit 10 and is connected to the prime mover 9. The first rotating shaft A1, which is arranged coaxially with the second rotating shaft A2, is rotatably supported by a support unit (not shown) and is connected to the second yoke unit 20 via a connecting member 95. The second yoke unit 20 may be connected to the pole piece unit 30 via a bearing.

[0021] The power generation principle of the magnetic-geared generator 2B is the same as that of the magnetic-geared generator 2A. When the second rotation shaft A2 rotates together with the first yoke unit 10 as the prime mover 9 is driven, the multiple first magnets 19 move relative to the multiple pole pieces 50 and the multiple second magnets 29, and the pole pieces 50 modulate the magnetic flux between the first yoke unit 10 and the second yoke unit 20. Therefore, the magnetic force caused by the modulation of the magnetic field causes the second yoke unit 20 to rotate together with the first rotation shaft A1. Electromagnetic induction occurs as the first yoke unit 10 and the second yoke unit 20 rotate, generating a current in the coil 99, allowing the magnetic-geared generator 2B to generate electricity.

[0022] In the magnetic-geared generator 2B illustrated in FIG. 1B , the first rotating shaft A1 may function as the input shaft instead of the second rotating shaft A2. Although detailed illustration is omitted, in this case, the prime mover 9 is coupled to the first rotating shaft A1. When the second yoke unit 20 rotates together with the first rotating shaft A1 due to the driving of the prime mover 9, the second magnets 29 move relative to the pole pieces 50 and the first magnets 19, and the pole pieces 50 modulate the magnetic flux between the first yoke unit 10 and the second yoke unit 20. The magnetic force resulting from the modulation of the magnetic field causes the first yoke unit 10 to rotate together with the second rotating shaft A2. Electromagnetic induction occurs as the first yoke unit 10 and the second yoke unit 20 rotate, generating a current in the coil 99, enabling the magnetic-geared generator 2B to generate electricity.

[0023] <1-2. Magnetic geared motor 3> The magnetic-geared motor 3A(3) illustrated in FIG. 1C has a similar configuration to the magnetic-geared generator 2A (see FIG. 1A). More specifically, the magnetic-geared motor 3A differs from the magnetic-geared generator 2A in that a coil 99 serving as a stator winding is electrically connected to the power supply source 6 and that a first rotating shaft A1 is connected to a rotating machine 8. In other respects, the magnetic-geared motor 3A has the same configuration as the magnetic-geared generator 2A. That is, the magnetic-geared motor 3A includes a housing 98, a first rotating shaft A1, a second rotating shaft A2, and a pair of end plates 97. In the example of FIG. 1C, the second yoke unit 20 functions as a stator, and the first yoke unit 10 and the pole piece unit 30 function as a rotor. The rotating machine 8 may be, for example, an electric vehicle driven by the magnetic-geared motor 3A(3). In this case, the first rotating shaft A1 may be connected to a drive shaft of the electric vehicle, which is a component of the rotating machine 8.

[0024] The magnetic-geared motor 3A rotates the first yoke unit 10 together with the second rotation axis A2 by a rotating magnetic field generated by energizing the coil 99. The first magnets 19 move circumferentially relative to the pole pieces 50 and the second magnets 29, causing the pole pieces 50 to modulate the magnetic flux between the first yoke unit 10 and the second yoke unit 20. The magnetic force generated by the modulated magnetic field rotates the pole pieces 50 together with the first rotation axis A1, and the magnetic-geared motor 3A can apply power to the rotating machine 8 via the first rotation axis A1. In the example of FIG. 1C , the above-mentioned configuration in which NL / NH is greater than 1 is adopted, so the first yoke unit 10 functions as a high-speed rotor and the pole piece unit 30 functions as a low-speed rotor.

[0025] The magnetic-geared motor 3B (3) illustrated in FIG. 1D has a similar configuration to the magnetic-geared generator 2B (see FIG. 1B). More specifically, the magnetic-geared motor 3B differs from the magnetic-geared generator 2B in that a coil 99 serving as a stator winding is electrically conductive with a power supply source 6 and that a first rotating shaft A1 is connected to a rotating machine 8. In other respects, the magnetic-geared motor 3B has the same configuration as the magnetic-geared generator 2B. That is, the magnetic-geared motor 3B includes a housing 96, a first rotating shaft A1, a second rotating shaft A2, and a connecting member 95. In the example of FIG. 1D, the pole piece unit 30 functions as a stator, and the first yoke unit 10 and the second yoke unit 20 function as rotors.

[0026] The operating principle of the magnetic-geared motor 3B is the same as that of the magnetic-geared motor 3A. That is, the second yoke unit 20 rotates due to a rotating magnetic field generated by energizing the coil 99. The second magnets 29 move circumferentially relative to the pole pieces 50 and the first magnets 19, causing the pole pieces 50 to modulate the magnetic flux between the first yoke unit 10 and the second yoke unit 20. The magnetic force generated by the modulated magnetic field rotates the first yoke unit 10, and the magnetic-geared motor 3A can apply power to the rotating machine 8 via the second rotating shaft A2. Note that the rotating machine 8 may be connected to the first rotating shaft A1 instead of the second rotating shaft A2. Even in this case, the magnetic-geared motor 3A can apply power to the rotating machine 8 via the first rotating shaft A1 using the same principle as described above.

[0027] <2. Example of the internal structure of the magnetic-geared electric machine 1> 2A and 2B are schematic diagrams showing the internal structure of a magnetic-geared electric machine 1 according to some embodiments of the present disclosure. In the schematic diagrams of FIGS. 2A and 2B, the circumferential direction is illustrated linearly. The multiple first magnets 19 are composed of magnets with different magnetic poles (north-pole magnets and south-pole magnets) arranged alternately in the circumferential direction. Similarly, the multiple second magnets 29 are composed of magnets with different magnetic poles (north-pole magnets and south-pole magnets) arranged alternately in the circumferential direction. A gap G1 is present between the pole piece 50 and the first yoke unit 10, and a gap G2 is present between the pole piece 50 and the second yoke unit 20.

[0028] The pole piece unit 30 includes an annular unit 35 (see FIG. 3) in which a plurality of pole pieces 50 are provided. However, the only component of the pole piece unit 30 illustrated in FIGS. 2A and 2B is the pole piece 50 (details of the annular unit 35 will be described later). FIG. 2A conceptually shows a first internal structure as an example of the internal structure of the magnetic-geared electric machine 1, and FIG. 2B conceptually shows a second internal structure as another example of the internal structure of the magnetic-geared electric machine 1.

[0029] <2-1. First internal structure> 2A, the first yoke unit 10 is disposed on the inner periphery side of the pole piece unit 30, and the second yoke unit 20 is disposed on the outer periphery side. A more detailed configuration is as follows.

[0030] The first yoke 15 includes a first body portion 11, which may be a core made of a soft magnetic material. The first body portion 11 illustrated in FIG. 2A has an outer peripheral surface 11B that supports a plurality of first magnets 19 arranged in the circumferential direction. The outer peripheral surface 11B is a curved surface formed over the entire circumferential length of the magnetic-geared electric machine 1. The second yoke 25 includes a second body portion 21, which may be a core made of a soft magnetic material, and a plurality of second teeth 21T that are spaced apart in the circumferential direction. In the example illustrated in FIG. 2A, the second body portion 21 has an inner peripheral surface 21A that faces the plurality of second magnets 29. Each second tooth 21T protrudes from the inner peripheral surface 21A toward the pole piece 50 and supports one or more second magnets 29. The second teeth 21T are made of a soft magnetic material and may be formed integrally with the second body portion 21. The second tooth portion 21T may be provided with a coil 99 (see FIGS. 1A and 2A) as the above-mentioned stator winding.

[0031] <2-2.Second internal structure> 2B, the second yoke unit 20 is disposed on the inner periphery side of the pole piece unit 30, and the first yoke unit 10 is disposed on the outer periphery side. A more detailed configuration is as follows.

[0032] The first yoke 15 includes a first body portion 11, which may be a core made of a soft magnetic material. The first body portion 11 illustrated in FIG. 2B has an inner circumferential surface 11A that supports a plurality of first magnets 19 arranged in the circumferential direction. The inner circumferential surface 11A is a curved surface formed over the entire circumferential length of the magnetic-geared electric machine 1. The second yoke 25 includes a second body portion 21, which may be a core made of a soft magnetic material, and a plurality of second teeth 21T spaced apart in the circumferential direction. In the example illustrated in FIG. 2B, the second body portion 21 has an outer circumferential surface 21B that faces a plurality of second magnets 29. The second teeth 21T protrude from the outer circumferential surface 21B toward the pole piece 50 and support one or more second magnets 29. The characteristics of the second teeth 21T, such as the material, are similar to those of the first internal structure, and therefore will not be described in detail.

[0033] <2-3. Examples of other internal structures> The magnetic-geared electric machine 1 may employ an internal structure different from the first internal structure and the second internal structure. For example, the first yoke 15 shown in FIGS. 2A and 2B may have a plurality of first teeth protruding toward the pole piece 50. In this case, the first teeth protrude from the inner circumferential surface 11A or the outer circumferential surface 11B of the first body portion 11 toward the pole piece 50, and the tips of the first teeth support one or more first magnets 19. Alternatively, the second yoke 25 shown in FIGS. 2A and 2B may not have the second teeth 21T. In this case, the inner circumferential surface 21A or the outer circumferential surface 21B of the second body portion 21 supports a plurality of second magnets 29. The first yoke unit 10 may employ an interior permanent magnet (IPM) structure in which a plurality of first magnets 19 are embedded in the first yoke 15. Similarly, the second yoke 25 may have an embedded magnet structure in which a plurality of second magnets 29 are embedded in the second yoke 25.

[0034] 3. Overview of the pole piece unit 30 3 is a schematic diagram of a pole piece unit 30 according to an embodiment of the present disclosure. The pole piece unit 30 includes an annular unit 35 extending in a circumferential direction about an axis O. The axis O is also the axis of the magnetic-geared electric machine 1. Therefore, the axial direction of the axis O (hereinafter sometimes simply referred to as the axial direction) is the axial direction of the magnetic-geared electric machine 1, and the radial direction of the annular unit 35 is the radial direction of the magnetic-geared electric machine 1. The pole piece unit 30 illustrated in the figure has an axially symmetrical shape.

[0035] Both axial ends of the annular unit 35 may be supported by the pair of end plates 97 (see FIGS. 1A and 2A), respectively. Alternatively, both axial ends of the annular unit 35 may be supported by a housing 98 (see FIGS. 1B and 2B). For convenience of explanation, the pair of end plates 97 and the housing 98 may hereinafter be collectively referred to as the support body 93 (see FIG. 4A).

[0036] The annular unit 35 includes a plurality of magnetic pole pieces 50 spaced apart in the circumferential direction and a plurality of non-magnetic bodies 53 spaced apart in the circumferential direction. The magnetic pole pieces 50 and the non-magnetic bodies 53 alternate in the circumferential direction, and each magnetic pole piece 50 is sandwiched between two non-magnetic bodies 53 in the circumferential direction. The non-magnetic bodies 53 are formed, for example, from carbon fiber reinforced plastic (CFRP). In the example shown in the figure, the magnetic pole pieces 50 are shorter than the non-magnetic bodies 53 in the axial direction. More specifically, both ends of the magnetic pole pieces 50 are located closer to the midpoint of the annular unit 35 than both ends of the non-magnetic bodies 53 in the axial direction. The centers of each magnetic pole piece 50 and each non-magnetic body 53 coincide with each other in the axial direction. Hereinafter, the magnetic pole pieces 50 and the non-magnetic bodies 53 will be collectively referred to as an annular portion 58.

[0037] The annular unit 35 further includes a pair of connecting portions 70 respectively connected to both axial ends of the annular portion 58. Each connecting portion 70 has a ring shape extending in the circumferential direction and is supported by the support body 93 described above. Each connecting portion 70 is fixed to the support body 93 by fastening means such as bolts. Each ring-shaped connecting portion 70 may be made of one or more conductive members. The conductive members are, for example, metals such as stainless steel. Note that the connecting portion 70 may also be made of one or more non-conductive members. The non-conductive members are, for example, plastics or rubber.

[0038] 3, the end face of each connecting portion 70 on the annular unit 35 side has a circumferentially extending uneven shape. A plurality of non-magnetic bodies 53 fit into the plurality of concave surfaces formed on the end face, and each of the plurality of convex surfaces formed on the end face abuts against a corresponding pole piece 50 sandwiched between two non-magnetic bodies 53. The end face of the connecting portion 70 is bonded to the plurality of non-magnetic bodies 53 and the plurality of pole pieces 50 via, for example, an adhesive layer 88 (see FIG. 4A).

[0039] In another embodiment, the pole pieces 50 and the non-magnetic bodies 53 may have approximately the same length in the axial direction, and the end face of the connecting portion 70 on the annular unit 35 side may be flat. In this case, for example, a structure may be employed in which the pair of connecting portions 70 respectively hold both ends of a support bar (not shown) that extends in the axial direction so as to penetrate the center of each pole piece 50. Furthermore, the pair of connecting portions 70 and the plurality of non-magnetic bodies 53 may be integrally configured. In this embodiment, at least a portion of the adhesive layer 88 is unnecessary.

[0040] In the pole piece unit 30 illustrated in Fig. 3, the annular unit 35 is fastened by an outer plate 37 (outer plate 137), an inner plate 33 (inner plate 133), and a fastening member 65. A more detailed structure will be described below in order for a first embodiment and a second embodiment. In order to avoid duplication of explanation, the structure of the pole piece unit 30, which has an axially symmetrical shape, will be described on one side of the center of the unit in the axial direction, and a description of the structure on the other side will be omitted.

[0041] 4. Details of the pole piece unit 31 (30) according to the first embodiment 4A to 4C, a pole piece unit 31 that is a pole piece unit 30 according to the first embodiment will be described. Below, a pole piece unit 31A (31) according to the first example and a pole piece unit 31B (31) according to the second example will be described in order.

[0042] <4-1. Pole piece unit 31A (31) according to the first example> 4A is a conceptual exploded view of the pole piece unit 31A (31), and is a cross-sectional view taken along the arrow AA in FIG. 3. The pole piece unit 31A (31) includes an inner cover 43 disposed on the inner circumferential surface of the annular unit 35, and an outer cover 47 disposed on the outer circumferential surface of the annular unit 35. Each of the inner cover 43 and the outer cover 47 is a cylinder formed of one or more members, and covers at least a portion of the annular unit 35 over its entire circumferential length. The member constituting each of the inner cover 43 and the outer cover 47 may be, for example, carbon fiber reinforced plastic (CFRP).

[0043] The pole piece unit 31A (31) illustrated in the figure includes an inner adhesive layer 91 interposed between the inner cover 43 and the annular unit 35, and an outer adhesive layer 92 interposed between the outer cover 47 and the inner plate 33A. In this embodiment, both the outer adhesive layer 92 and the inner adhesive layer 91 are arranged so as to overlap the connecting portion 70 and the pole piece 50 in the axial direction. In other words, both the outer adhesive layer 92 and the inner adhesive layer 91 are arranged so as to be aligned radially with the connecting portion 70 and the pole piece 50. Although not shown, both adhesive layers are also arranged so as to overlap the non-magnetic material 53 in the axial direction. Note that the inner adhesive layer 91 is preferably arranged so as to be aligned radially with a portion of the connecting portion 70, avoiding the support 93.

[0044] In this embodiment, at least half (more preferably, two-thirds or more) of the outer peripheral surface of the inner cover 43 is covered by the inner adhesive layer 91. Even more preferably, the entire outer peripheral surface of the inner cover 43 is covered by the inner adhesive layer 91. Furthermore, at least half (more preferably, two-thirds or more) of the inner peripheral surface of the outer cover 47 is covered by the outer adhesive layer 92. Even more preferably, the entire inner peripheral surface of the outer cover 47 is covered by the outer adhesive layer 92. The thickness (i.e., radial dimension) of each of the outer adhesive layer 92 and the inner adhesive layer 91 is one-tenth or less of the radial dimension of each of the outer cover 47 and the inner cover 43.

[0045] The pole piece unit 31A (31) further includes an inner plate 33A (33) disposed on the inner circumferential surface of the inner cover 43, and an outer plate 37A (37) disposed on the outer circumferential surface of the outer cover 47. At least a portion of the inner plate 33A is disposed so as to overlap a portion of the connecting portion 70 in the axial direction, and at least a portion of the outer plate 37A is disposed so as to overlap the inner plate 33A in the axial direction. In other words, at least a portion of the inner plate 33A and at least a portion of the outer plate 37A are disposed so as to be aligned radially with the connecting portion 70.

[0046] The pole piece unit 31A further includes a fastening member 65. A shaft 61, which is a component of the fastening member 65, is arranged so as to radially penetrate the outer plate 37A, the outer cover 47, the connecting portion 70, the inner cover 43, and the inner plate 33A. In this example, the shaft 61 is also arranged so as to penetrate the inner adhesive layer 91 and the outer adhesive layer 92. The fastening member 65 may be a bolt or a screw. The fastening member 65 illustrated in the figure is a bolt, and a nut 68 is inserted into the shaft 61 protruding radially from the inner plate 33. The nut 68 and a head 65A of the fastening member 65 radially sandwich the inner plate 33A and the outer plate 37A. In this example, the fastening member 65 and the nut 68 form a fastening unit, and multiple fastening units are arranged at intervals in the circumferential direction.

[0047] According to the above configuration, the inner cover 43, the annular unit 35, and the outer cover 47 are sandwiched and reinforced in the radial direction by the fastening structure consisting of the inner plate 33A, the outer plate 37A, and the fastening member 65. This improves the strength of the pole piece unit 31 (30). Furthermore, during operation of the magnetic-geared electric machine 1, electromagnetic forces directed radially outward and radially inward repeatedly act on each of the multiple pole pieces 50, which may cause the pole pieces 50 to peel off from the connecting portions 70 (or the adhesive layer 88 attached to the connecting portions 70). Furthermore, in an embodiment in which the pole piece unit 30 functions as a rotor (see FIGS. 1A and 1C), centrifugal force is also applied to the pole piece unit 30, making peeling even more of a concern. In this regard, according to the above configuration, the pole pieces 50 are more firmly sandwiched between the inner cover 43 and the outer cover 47, thereby reinforcing the pole pieces 50. This makes it possible to prevent the pole pieces 50 from peeling off from the connecting portions 70 (or the adhesive layers 88 that are adhered to the connecting portions 70). This also makes it possible to prevent the pole pieces 50 that have come off from the connecting portions 70 from hitting the first yoke unit 10 or the second yoke unit 20, which are other components of the magnetic-geared electric machine 1. As mentioned above, the connecting portion 70 and the pole piece 50 may be connected by a support bar instead of by the adhesive layer 88. Even in this case, the advantage of being able to prevent the pole piece 50 from coming off the connecting portion 70 due to the increased strength of the pole piece unit 31 (30) is obtained. Furthermore, the pole piece unit 30 does not need to have an axially symmetrical shape. More specifically, a fastening structure consisting of the inner plate 33A, the outer plate 37A, and the fastening member 65 may be provided only on one axial side of the annular unit 35. Even in this case, the above-mentioned advantage is obtained. Furthermore, the above-mentioned advantage is also obtained in an embodiment in which the pole piece unit 30 functions as a stator (see FIGS. 1B and 2B).

[0048] In the example of FIG. 4A , at least one of the inner plate 33A and the outer plate 37A is a conductor spaced apart from the pole pieces 50 in the axial direction. The conductor may be a metal such as stainless steel. In the example of FIG. 4A , both the inner plate 33A and the outer plate 37A are spaced apart from the pole pieces 50 in the axial direction. In other words, the inner plate 33A and the outer plate 37A are arranged so as to be radially aligned only with respect to the connecting portion 70 or the pole pieces 50. Note that in this embodiment, in which the non-magnetic material 53 is axially longer than the pole pieces 50, the inner plate 33A or the outer plate 37A may be arranged so as to overlap the non-magnetic material 53 in the axial direction. In other words, the inner plate 33A or the outer plate 37A may be arranged so as to be radially aligned with one end of the non-magnetic material 53.

[0049] According to the above configuration, the inner plate 33A and the outer plate 37A, which serve as conductors, are spaced axially away from the plurality of pole pieces 50. This makes it possible to prevent vortex-linked currents, which are generated in the pole pieces 50 as the magnetic-geared electric machine 1 operates, from flowing through the conductors, thereby suppressing eddy current loss in the magnetic-geared electric machine 1. Either the inner plate 33A or the outer plate 37A may be a conductor arranged radially aligned with the pole piece 50. Even in this case, the above-mentioned advantages can be obtained.

[0050] <4-2. Pole piece unit 31B (31) according to the second example> 4B is a schematic diagram showing a pole piece unit 31B (31) according to a second example, and is a cross-sectional view taken along the line AA in FIG. 3. The pole piece unit 31B includes an inner plate 33B (33) and an outer plate 37B (37) instead of the inner plate 33A and the outer plate 37A. Otherwise, the pole piece unit 31B has the same configuration as the pole piece unit 31A.

[0051] At least one of the inner plate 33B and the outer plate 37B is arranged to overlap the connecting portion 70 and the pole piece 50 in the axial direction. In the example shown in the figure, both the inner plate 33B and the outer plate 37B are arranged to overlap the connecting portion 70 and the pole piece 50 in the axial direction. In other words, the inner plate 33B and the outer plate 37B are arranged to be aligned radially with the connecting portion 70 and the pole piece 50. The inner plate 33B and the outer plate 37B also extend circumferentially and are arranged to be aligned radially with the non-magnetic material 53. The inner plate 33B and the outer plate 37B are fastened together by fastening members 65, as in the first example.

[0052] According to the above configuration, the pole piece 50 is positioned between the inner plate 33 and the outer plate 37, so the force generated by sandwiching the inner plate 33 and the outer plate 37 is easily transmitted to the pole piece 50. The reinforcing effect of the pole piece 50 is improved, so that the pole piece 50 can be further prevented from coming off the connecting portion 70. Either the inner plate 33B or the outer plate 37B may be disposed on one axial side of the pole piece 50 with a gap therebetween. Even in this case, the above advantages can be obtained. However, it is preferable that at least the inner plate 33B of the inner plate 33B or the outer plate 37B be disposed so as to overlap the pole piece 50 in the axial direction. This is because the inner plate 33B can indirectly support the pole piece 50.

[0053] 4C is a schematic diagram of a second exemplary pole piece unit 31B (31) applied to the first internal structure (the inner adhesive layer 91 and the outer adhesive layer 92 are not shown). With reference to this figure, the configuration of the pole piece unit 31B will be described in more detail.

[0054] The inner plate 33B (33) may include an inner contact surface 333 that contacts the inner cover 43 and a first opposite surface 331 opposite to the inner contact surface 333. Furthermore, the first opposite surface 331 has a first tapered surface 339 that extends so that the distance from the inner contact surface 333 decreases toward the opposite (other) side in the axial direction. The first tapered surface 339 may be a flat surface as shown in the figure, or may be a curved surface not shown. In the example shown in the figure, the first tapered surface 339 faces the first yoke unit 10 with a gap G1 between them. In other embodiments, the pole piece unit 31B may be applied to the second internal structure, and the first tapered surface 339 may face the second yoke unit 20 with a gap G2 between them.

[0055] According to the above configuration, even if a radial force generated in the pole piece 50 is transmitted to the inner plate 33B during operation of the magnetic-geared electric machine 1, the stress is dispersed at the first tapered surface 339 of the inner plate 33B. Suppressing stress concentration on the inner plate 33B makes it possible to suppress damage to the inner plate 33B. Furthermore, since the inner plate 33B has the first tapered surface 339, it is possible to prevent the gap (gap G1 or gap G2) between the pole piece unit 31B and another component (first yoke unit 10 or second yoke unit 20) of the magnetic-geared electric machine 1 from becoming excessively small, thereby suppressing contact between the pole piece unit 31B and the other component. The first tapered surface 339 may be provided on the pole piece unit 31A according to the first example, and the above advantages can be obtained even in this case.

[0056] As illustrated in FIG. 4C , the outer plate 37B (37) includes an outer abutment surface 377 that abuts against the outer cover 47 and a second opposite surface 372 opposite to the outer abutment surface 377. The second opposite surface 372 has a second tapered surface 379 that extends so that the distance from the outer abutment surface 377 decreases toward the opposite (other) side in the axial direction. The second tapered surface 379 may be a flat surface as shown in the figure, or may be a curved surface (not shown). In the example shown in the figure, the second tapered surface 379 faces the second yoke unit 20 with a gap G2 between them. In other embodiments, the pole piece unit 31B may be applied to the second internal structure, and the second tapered surface 379 may face the first yoke unit 10 with a gap G1 between them.

[0057] According to the above configuration, even if a radial force generated in the pole piece 50 is transmitted to the outer plate 37B during operation of the magnetic-geared electric machine 1, the stress is dispersed at the second tapered surface 379 of the outer plate 37B. Suppressing stress concentration on the outer plate 37B makes it possible to suppress damage to the outer plate 37B. Furthermore, since the outer plate 37B has the second tapered surface 379, it is possible to prevent the gap (gap G2 or gap G1) between the pole piece unit 31B and another component (second yoke unit 20 or first yoke unit 10) of the magnetic-geared electric machine 1 from becoming excessively small, thereby suppressing contact between the pole piece unit 31B and the other component. The second tapered surface 379 may be provided on the pole piece unit 31A according to the first example, and the above advantages can be obtained even in this case.

[0058] 5. Details of the pole piece unit 32 according to the second embodiment 5A is a conceptual exploded view of the pole piece unit 32 (30) according to the second embodiment, and is a cross-sectional view taken along the arrow AA in FIG. 3. FIG. 5B is a schematic diagram showing the annular portion 58 of the pole piece unit 32 according to the second embodiment. In this figure, the annular portion 58 is shown viewed along the radial direction, and the circumferential direction is shown linearly. FIG. 5C is a schematic diagram of a first internal structure to which the pole piece unit according to the second embodiment is applied.

[0059] 5A, the outer cover 47, the outer adhesive layer 92, the inner cover 43, and the inner adhesive layer 91 (see FIGS. 4A and 4B) are not provided. Also, the pole piece unit 32 according to the second embodiment includes an inner plate 133 and an outer plate 137 instead of the inner plate 33 and the outer plate 37.

[0060] The inner plate 133 is disposed on the inner circumferential surface of the annular unit 35, and is formed from the inner circumferential surfaces of the pole pieces 50 and non-magnetic material 53 to the inner circumferential surface of the connecting portion 70. The pole piece unit 32 of this embodiment includes a plurality of inner plates 133 arranged in the circumferential direction, and the plurality of inner plates 133 form an annular shape. The arrangement range of one inner plate 133 is, for example, the area indicated by the two-dot chain line J1 shown in FIG. 5B. Note that the inner plate 133 may be a ring-shaped member formed from a single member.

[0061] The outer plate 137 is disposed on the outer peripheral surface of the annular unit 35, and is formed from the outer peripheral surfaces of the pole pieces 50 and non-magnetic material 53 to the outer peripheral surface of the connecting portion 70. The pole piece unit 32 of this embodiment includes a plurality of outer plates 137 arranged in the circumferential direction, and the plurality of outer plates 137 form an annular shape. The arrangement range of one outer plate 137 is, for example, the area indicated by the two-dot chain line J1 shown in FIG. 5B. The outer plate 137 may also be a ring-shaped plate formed from a single member.

[0062] 5A includes a shaft portion 61 that is disposed so as to radially penetrate the outer plate 137, the connecting portion 70, and the inner plate 133. In the example shown in the same figure, the fastening member 65 is a bolt, and a nut 68 is inserted into the shaft portion 61 that protrudes radially from the inner plate 133. The fastening member 65, the outer plate 137, and the inner plate 133 radially sandwich the connecting portion 70 and the annular portion 58. In other embodiments, the fastening member 65 may be a screw.

[0063] According to the above configuration, the annular unit 35 is sandwiched and reinforced in the radial direction by the fastening structure consisting of the inner plate 133, the outer plate 137, and the fastening member 65. This improves the strength of the pole piece unit 32 (30). Furthermore, during operation of the magnetic-geared electric machine 1, electromagnetic forces directed radially outward and radially inward repeatedly act on each of the multiple pole pieces 50, which may cause the pole pieces 50 to peel off from the connecting portions 70 (or the adhesive layer 88 attached to the connecting portions 70). Furthermore, in an embodiment in which the pole piece unit 30 functions as a rotor (see FIGS. 1A and 1C), centrifugal force also acts on the pole piece unit 30, making peeling even more of a concern. In this regard, according to the above configuration, the pole pieces 50 are firmly sandwiched between the inner plate 133 and the outer plate 137, thereby reinforcing the pole pieces 50. This makes it possible to prevent the pole pieces 50 from peeling off from the connecting portions 70 (or the adhesive layers 88 that are adhered to the connecting portions 70). This also makes it possible to prevent the pole pieces 50 that have come off from the connecting portions 70 from hitting the first yoke unit 10 or the second yoke unit 20, which are other components of the magnetic-geared electric machine 1. As mentioned above, the connecting portion 70 and the pole piece 50 may be connected by a support bar instead of by the adhesive layer 88. Even in this case, the advantage of being able to prevent the pole piece 50 from coming off the connecting portion 70 due to the increased strength of the pole piece unit 32 is obtained. The above advantage is also obtained in the embodiment in which the pole piece unit 30 functions as a stator (see FIGS. 1B and 2B).

[0064] In the second embodiment, at least one of the inner plate 133 and the outer plate 137 is an insulator. The insulator may be carbon fiber reinforced plastic (CFRP), ceramic, or the like. With the above configuration, during operation of the magnetic-geared electric machine 1, vortex-linked currents generated in the pole pieces 50 can be prevented from flowing through at least one of the inner plate 133 and the outer plate 137, thereby suppressing eddy current loss. Either the inner plate 133 or the outer plate 137 may be a conductor. Even in this case, the above-mentioned advantages can be obtained by making the other of the inner plate 133 and the outer plate 137 an insulator.

[0065] As illustrated in Fig. 5C, the inner plate 133 has the same components as the inner plate 33B according to the first embodiment (see Fig. 4C). That is, the inner plate 133 has an inner abutment surface 333 and a first opposite surface 331, and the first opposite surface 331 has a first tapered surface 339. Details of the above components have been described above. Even if a radial force generated in the pole piece 50 is transmitted to the inner plate 133 during operation of the magnetic-geared electric machine 1, the stress is dispersed at the first tapered surface 339 of the inner plate 133. By suppressing stress concentration in the inner plate 133, damage to the inner plate 133 can be suppressed. Furthermore, since the inner plate 133 has the first tapered surface 339, the gap (gap G1 or gap G2) between the pole piece unit 32 and other components (first yoke unit 10 or second yoke unit 20) of the magnetic-geared electric machine 1 can be prevented from becoming excessively small, and contact between the pole piece unit 32 and other components can be prevented.

[0066] As illustrated in Fig. 5C, the outer plate 137 has the same components as the outer plate 37B (37) according to the first embodiment. That is, the outer plate 137 has an outer abutment surface 377 and a second opposite surface 372, and the second opposite surface 372 has a second tapered surface 379. Details of the above components have been described above. Even if a radial force generated in the pole piece 50 is transmitted to the outer plate 137 during operation of the magnetic-geared electric machine 1, the stress is dispersed at the second tapered surface 379 of the outer plate 137. Suppressing stress concentration in the outer plate 137 can suppress damage to the outer plate 137. Furthermore, since the outer plate 137 has the second tapered surface 379, the gap (gap G2 or gap G1) between the pole piece unit 31B and other components of the magnetic-geared electric machine 1 (the second yoke unit 20 or the first yoke unit 10) can be prevented from becoming excessively small, and contact between the pole piece unit 32 and other components can be prevented.

[0067] <6. Summary> The contents of the above-described embodiments can be understood, for example, as follows.

[0068] 1) A pole piece unit (30) for a magnetic-geared electric machine according to at least one embodiment of the present disclosure comprises: An annular unit (35) extending circumferentially about an axis (O), a plurality of magnetic pole pieces (50) spaced apart in the circumferential direction; a plurality of non-magnetic bodies (53) arranged at intervals in the circumferential direction, the non-magnetic bodies (53) alternating with the plurality of magnetic pole pieces (50); and an annular unit (35) including a connecting portion (70) connected to an end of each of the magnetic pole pieces (50) and an end of each of the non-magnetic bodies (53) on one axial side of the axis (O); an inner cover (43) disposed on the inner circumferential surface of the annular unit (35); an inner plate (33) disposed on an inner peripheral surface of the inner cover (43), the inner plate (33) being disposed so as to overlap at least the connecting portion (70) in the axial direction; an outer cover (47) disposed on the outer peripheral surface of the annular unit (35); an outer plate disposed on an outer peripheral surface of the outer cover (47), the outer plate being disposed so as to at least partially overlap with the inner plate (33) in the axial direction; a fastening member (65) including a shaft portion (61) arranged to penetrate the outer plate, the outer cover (47), the connecting portion (70), the inner cover (43), and the inner plate (33) in the radial direction of the annular unit (35); Equipped with.

[0069] According to the configuration 1), the inner cover 43, the annular unit 35, and the outer cover 47 are radially sandwiched and reinforced by the fastening structure consisting of the inner plate 33, the outer plate, and the fastening member 65. This improves the strength of the pole piece unit 30. Therefore, during operation of the magnetic-geared electric machine 1, the pole piece 50 is prevented from coming off the connecting portion 70 due to the electromagnetic force acting on the pole piece 50. Furthermore, the pole piece 50 that has come off the connecting portion 70 is prevented from hitting other components of the magnetic-geared electric machine 1.

[0070] 2) In some embodiments, the pole piece unit (30) described in 1) above, At least one of the inner plate (33) and the outer plate (50) is an electric conductor that is spaced apart from the magnetic pole pieces (50) on the one side in the axial direction.

[0071] According to the configuration 2), the conductor is spaced apart from the plurality of pole pieces 50. This prevents vortex-linked currents, which are generated in the pole pieces 50 as the magnetic-geared electric machine 1 operates, from flowing through the conductor, thereby reducing eddy current loss.

[0072] 3) In some embodiments, the pole piece unit (30) described in 1) above, At least one of the inner plate (33) and the outer plate (50) is arranged to overlap the connecting portion (70) and the pole piece (50) in the axial direction.

[0073] According to the configuration 3), the pole piece 50 is positioned between the inner plate 33 and the outer plate, so that the force generated by sandwiching the inner plate 33 and the outer plate is easily transmitted to the pole piece 50. The reinforcing effect of the pole piece 50 is improved, which further prevents the pole piece 50 from coming off the connecting portion 70.

[0074] 4) In some embodiments, the pole piece unit (30) according to any one of 1) to 3) above, the inner plate (33) includes an inner abutment surface (333) that abuts against the inner cover (43) and a first opposite surface (331) opposite to the inner abutment surface (333), The first opposite surface (331) has a first tapered surface (339) extending in a direction opposite to the one side in the axial direction so that the distance from the inner contact surface (333) becomes smaller.

[0075] According to the configuration of 4) above, even if a radial force generated in the pole piece 50 is transmitted to the inner plate 33 during operation of the magnetic-geared electric machine 1, the stress is dispersed at the first tapered surface 339 of the inner plate 33. Suppressing stress concentration on the inner plate 33 can suppress damage to the inner plate 33. Furthermore, since the inner plate 33 has the first tapered surface 339, it can suppress excessively small gaps between the pole piece unit 30 and other components of the magnetic-geared electric machine 1, thereby suppressing contact between the pole piece unit 30 and other components.

[0076] 5) In some embodiments, the pole piece unit (30) according to any one of 1) to 4) above, The outer plate includes an outer abutment surface (377) that abuts against the outer cover (47) and a second opposite surface (372) opposite to the outer abutment surface (377), The second opposite surface (372) has a second tapered surface (379) extending in a direction opposite to the one side in the axial direction so that the distance from the outer contact surface (377) becomes smaller.

[0077] According to the configuration of 5) above, even if a radial force generated in the pole piece 50 is transmitted to the outer plate during operation of the magnetic-geared electric machine 1, the stress is dispersed at the second tapered surface 379 of the outer plate. Suppressing stress concentration on the outer plate reduces damage to the outer plate. Furthermore, since the outer plate has the second tapered surface 379, excessively small clearances between the pole piece unit 30 and other components of the magnetic-geared electric machine 1 can be prevented, thereby reducing contact between the pole piece unit 30 and other components.

[0078] 6) A pole piece unit (30) for a magnetic-geared electric machine according to at least one embodiment of the present disclosure comprises: An annular unit (35) extending circumferentially about an axis (O), a plurality of magnetic pole pieces (50) spaced apart in the circumferential direction; a plurality of non-magnetic bodies (53) arranged at intervals in the circumferential direction, the non-magnetic bodies (53) alternating with the plurality of magnetic pole pieces (50); and an annular unit (35) including a connecting portion (70) connected to an end of each of the magnetic pole pieces (50) and an end of each of the non-magnetic bodies (53) on one axial side of the axis (O); an inner plate (133) disposed on the inner peripheral surface of the annular unit (35), the inner plate (133) being formed from the inner peripheral surface of the connecting portion (70) to the inner peripheral surface of the pole piece (50) and the inner peripheral surface of the non-magnetic body (53); an outer plate (137) disposed on the outer peripheral surface of the annular unit (35), the outer plate (137) being formed from the outer peripheral surface of the connecting portion (70) to the outer peripheral surface of the pole piece (50) and the outer peripheral surface of the non-magnetic body (53); a fastening member (65) including a shaft portion (61) arranged to penetrate the outer plate (137), the connecting portion (70), and the inner plate (133) in the radial direction of the annular unit (35); Equipped with.

[0079] According to the configuration 6) above, the annular unit 35 is sandwiched and reinforced in the radial direction by the fastening structure consisting of the inner plate 133, the outer plate 137, and the fastening member 65. This improves the strength of the pole piece unit 30. Therefore, during operation of the magnetic-geared electric machine 1, the pole piece 50 is prevented from coming off the connecting portion 70 due to the electromagnetic force acting on the pole piece 50. Furthermore, the pole piece 50 that has come off the connecting portion 70 is prevented from hitting other components of the magnetic-geared electric machine 1.

[0080] 7) In some embodiments, the pole piece unit (30) described in 6) above, At least one of the inner plate (133) or the outer plate (137) is an insulator.

[0081] According to the configuration of 7) above, when the magnetic-geared electric machine (1) is operating, vortex-linked currents generated in the pole pieces (50) can be prevented from flowing through at least one of the inner plate (133) and the outer plate (137), thereby suppressing eddy current loss.

[0082] 8) In some embodiments, the pole piece unit (30) described in 6) or 7) above, the inner plate (133) includes an inner abutment surface (333) that abuts against the annular unit (35) and a first opposite surface (331) opposite to the inner abutment surface (333), The first opposite surface (331) has a first tapered surface (339) extending in a direction opposite to the one side in the axial direction so that the distance from the inner contact surface (333) becomes smaller.

[0083] According to the configuration 8) above, the same advantages as those of 4) above can be obtained.

[0084] 9) In some embodiments, the pole piece unit (30) according to any one of 6) to 8) above, the outer plate (137) includes an outer abutment surface (377) that abuts against the annular unit (35) and a second opposite surface (372) opposite to the outer abutment surface (377), The second opposite surface (372) has a second tapered surface (379) extending in a direction opposite to the one side in the axial direction so that the distance from the outer contact surface (377) becomes smaller.

[0085] According to the configuration 9) above, the same advantages as those of 5) above can be obtained.

[0086] 10) A magnetic-geared electric machine (1) according to at least one embodiment of the present disclosure includes: A magnetic pole piece unit (30) according to any one of 1) to 9) above; a first yoke unit (10) including a plurality of first magnets (19) arranged in the circumferential direction on the outside or inside of the annular unit (35) and a first yoke (15) supporting the plurality of first magnets (19); The annular unit (35) is provided with a second yoke unit (20) including a plurality of second magnets (29) arranged in the circumferential direction on the inside or outside of the annular unit (35), and a second yoke unit (20) including a second yoke (25) that supports the plurality of second magnets.

[0087] According to the configuration of 10) above, for the same reason as in 1), the magnetic-geared electric machine (1) is obtained.

[0088] The above describes embodiments of the present disclosure, but the present disclosure is not limited to the above-described embodiments, and also includes forms in which the above-described embodiments are modified, or forms in which these forms are appropriately combined.

[0089] In this specification, expressions expressing relative or absolute arrangement such as "in a certain direction," "along a certain direction," "parallel," "orthogonal," "center," "concentric," or "coaxial" not only express such an arrangement strictly, but also express a state in which there is a relative displacement with a tolerance or an angle or distance to the extent that the same function is obtained. For example, expressions such as "identical," "equal," and "homogeneous" that indicate that something is in an equal state not only indicate a state of strict equality, but also indicate a state in which there is a tolerance or a difference to the extent that the same function is obtained. Furthermore, in this specification, expressions representing shapes such as a rectangular shape or a cylindrical shape not only represent rectangular shapes or cylindrical shapes in the strict geometric sense, but also represent shapes including uneven portions, chamfered portions, etc., to the extent that the same effect can be obtained. Furthermore, in this specification, the expressions "comprise," "include," or "have" a component are not exclusive expressions that exclude the presence of other components. [Explanation of symbols]

[0090] 1: Magnetic-geared electric machine 10: First yoke unit 11A: Inner surface 11B: Outer surface 15: First yoke 19: First magnet 20: Second yoke unit 21A: Inner surface 21B: Outer surface 25: Second yoke 29: Second magnet 31, 32(30): Pole piece unit 33, 133: Inner plate 35: Annular unit 37, 137: Outer plate 43: Inner cover 47: Outer cover 50 :Magnetic pole piece 53: Non-magnetic material 61: Shaft 65: Fastening member 70:Connection part 331: Opposite side of No. 1 333: Inner contact surface 339: First tapered surface 372: 2nd opposite side 377:Outer contact surface 379: Second tapered surface O: Axis line

Claims

1. An annular unit extending circumferentially about an axis, a plurality of circumferentially spaced pole pieces; a plurality of non-magnetic bodies arranged at intervals in the circumferential direction, the non-magnetic bodies alternating with the plurality of magnetic pole pieces; and an annular unit including a connecting portion connected to an end of each of the magnetic pole pieces and an end of each of the non-magnetic bodies on one axial side of the axis; an inner cover disposed on an inner circumferential surface of the annular unit; an inner plate disposed on an inner circumferential surface of the inner cover so as to overlap at least the connecting portion in the axial direction; an outer cover disposed on an outer peripheral surface of the annular unit; an outer plate disposed on an outer peripheral surface of the outer cover so as to overlap at least a portion of the inner plate in the axial direction; a fastening member including a shaft portion disposed to penetrate the outer plate, the outer cover, the connecting portion, the inner cover, and the inner plate in a radial direction of the annular unit; A pole piece unit comprising:

2. At least one of the inner plate and the outer plate is a conductor that is spaced apart from the plurality of magnetic pole pieces on the one side in the axial direction. The pole piece unit of claim 1 .

3. At least one of the inner plate and the outer plate is arranged to overlap the connecting portion and the pole piece in the axial direction. The pole piece unit of claim 1 .

4. the inner plate includes an inner abutment surface that abuts against the inner cover and a first opposite surface opposite to the inner abutment surface, the first opposite surface has a first tapered surface extending such that the distance between the first opposite surface and the inner abutment surface decreases toward the opposite side from the one side in the axial direction; A pole piece unit according to any one of claims 1 to 3.

5. the outer plate includes an outer abutment surface that abuts against the outer cover and a second opposite surface opposite to the outer abutment surface, the second opposite surface has a second tapered surface extending such that the distance from the outer contact surface decreases toward the opposite side from the one side in the axial direction; A pole piece unit according to any one of claims 1 to 3.

6. An annular unit extending circumferentially about an axis, a plurality of circumferentially spaced pole pieces; a plurality of non-magnetic bodies arranged at intervals in the circumferential direction, the non-magnetic bodies alternating with the plurality of magnetic pole pieces; and an annular unit including a connecting portion connected to an end of each of the magnetic pole pieces and an end of each of the non-magnetic bodies on one axial side of the axis; an inner plate disposed on an inner peripheral surface of the annular unit, the inner plate extending from the inner peripheral surface of the connecting portion to the inner peripheral surface of the pole piece and the inner peripheral surface of the non-magnetic body; an outer plate disposed on an outer peripheral surface of the annular unit, the outer plate extending from an outer peripheral surface of the connecting portion to an outer peripheral surface of the pole piece and an outer peripheral surface of the non-magnetic body; a fastening member including a shaft portion disposed to penetrate the outer plate, the connecting portion, and the inner plate in a radial direction of the annular unit; A pole piece unit comprising:

7. At least one of the inner plate and the outer plate is an insulator.

7. The pole piece unit of claim 6.

8. the inner plate includes an inner abutment surface that abuts against the annular unit and a first opposite surface opposite to the inner abutment surface, the first opposite surface has a first tapered surface extending such that the distance between the first opposite surface and the inner abutment surface decreases toward the opposite side from the one side in the axial direction; 8. A pole piece unit according to claim 6 or 7.

9. the outer plate includes an outer abutment surface that abuts against the annular unit and a second opposite surface opposite to the outer abutment surface, the second opposite surface has a second tapered surface extending such that the distance from the outer contact surface decreases toward the opposite side from the one side in the axial direction; 8. A pole piece unit according to claim 6 or 7.

10. A pole piece unit according to claim 1 or 6; a first yoke unit including a plurality of first magnets arranged in the circumferential direction on the outer or inner side of the annular unit, and a first yoke supporting the plurality of first magnets; a second yoke unit including a plurality of second magnets arranged in the circumferential direction on the inside or outside of the annular unit, and a second yoke supporting the plurality of second magnets; 1. A magnetic-geared electric machine comprising:

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