Stator core, stator, rotating electrical machine, and method for manufacturing stator core

Abstract

A stator (200) has a core (230). The core (230) has teeth (231) and a flange (235). The teeth (231) are laminated cores. The teeth (231) are formed so as to include a plurality of magnetic plate materials (232). The plurality of magnetic plate materials (232) are laminated in a radial direction (RD). The plurality of magnetic plate materials (232) are joined to each other by a plate adhesion part. The flange (235) is a dust core. The flange (235) is formed so as to contain a magnetic powder (236). The flange (235) is formed by press working or the like of the magnetic powder (236). In the flange (235), a plurality of magnetic powders (236) are in an aggregated state. The plurality of magnetic powders (236) are joined to each other with an insulating coating therebetween.

Description

Stator Core, Rotating Electric Machine, and Method for Manufacturing Stator Core Cross - reference to Related Applications

[0001] This application is based on Japanese Patent Application No. 2024 - 173490 filed in Japan on October 2, 2024, the contents of which are incorporated herein by reference in their entirety.

[0002] The disclosure in this specification relates to a stator core, a rotating electric machine, and a method for manufacturing a stator core.

[0003] Patent Document 1 describes a motor having a stator and a rotor. In this motor, the stator has a stator core. The stator core is formed by laminating a plurality of electromagnetic steel sheets.

[0004] Japanese Unexamined Patent Application Publication No. 2015 - 180150

[0005] In the above Patent Document 1, it is considered that since a plurality of electromagnetic steel sheets are laminated, eddy currents are less likely to occur in the stator core due to the magnetic flux passing through the stator core. However, even if a plurality of electromagnetic steel sheets are laminated, depending on the direction in which the magnetic flux passes through the stator core, eddy currents may easily occur in the stator core. If eddy currents occur in the stator core, there is a concern that the loss in the motor will increase.

[0006] One object of the present disclosure is to provide a stator core, a rotating electric machine, and a method for manufacturing a stator core that can reduce losses.

[0007] The plurality of aspects disclosed in this specification employ different technical means to achieve their respective objects. Also, the claims and the reference numerals in parentheses described in this section are an example showing the correspondence relationship with the specific means described in the embodiments described later as one aspect, and do not limit the technical scope.

[0008] To achieve the above objective, the disclosed embodiment is a stator core provided in the stator of a rotating electric machine, to which an energizable coil portion is attached, comprising: a first core member having a plate-shaped first member and formed by joining a plurality of stacked first members to each other; and a second core member having a second member smaller than the first member and formed by joining a plurality of assembled second members to each other.

[0009] According to the stator core described above, the stator core has a first core member and a second core member. In this configuration, even with the laminated structure of the first core member, the magnetic flux passing through in a direction where eddy currents are likely to occur can be suppressed by the aggregate structure of the second core member. Therefore, losses caused by eddy currents in the stator core can be reduced.

[0010] The disclosed embodiment is a rotating electric machine driven by the supply of power, comprising: a stator having an energizable coil section and a stator core to which the coil section is attached; and a rotor that rotates about a rotation axis relative to the stator, wherein the stator core comprises a first core member having a first plate-shaped member and a plurality of stacked first members joined together, and a second core member having a second member smaller than the first member and a plurality of assembled second members joined together.

[0011] According to the above-described rotating electric machine, losses caused by eddy currents can be reduced, similar to the stator core described above.

[0012] The disclosed embodiment is a manufacturing method for a stator core provided in the stator of a rotating electric machine and to which an energizable coil portion is attached, comprising: a first preparation step of preparing a first core member having a first member formed in the shape of a plate, and a plurality of stacked first members being joined together; a second preparation step of preparing a second core member having a second member smaller than the first member, and a plurality of assembled second members being joined together; and a fixing step of fixing the first core member and the second core member.

[0013] According to the above-described method for manufacturing a stator, a stator core can be formed by fixing the first core member and the second core member. Therefore, similar to the above-described stator core, losses caused by eddy currents can be reduced.

[0014] A diagram showing the configuration of the eVTOL in the first embodiment. A diagram showing the electrical configuration of the propulsion system. A schematic perspective view of the EPU. A schematic longitudinal section view of the motor device. A perspective view of the stator and motor housing. A plan view of the core piece and motor housing. A diagram showing the first and second magnetic fluxes in the plan view of the core piece. A diagram showing the first and second magnetic fluxes in the side view of the core piece. A diagram showing the first and second magnetic fluxes in a view of the core piece from the outer circumference. A perspective view of the core. A diagram showing the structure of the teeth and the structure of the flange. A diagram for explaining the first eddy current. A diagram for explaining the second eddy current. A flowchart showing the procedure of the manufacturing process of the motor device. A perspective view of the teeth. A perspective view of the teeth with bobbin. An exploded perspective view of the teeth with bobbin and flange. A perspective view of the core with bobbin. A perspective view of the core with coil section. A perspective view of the core piece. A side view of the core in modified example 1-1. A side view of the core in modified example 1-2. A diagram showing the schematic configuration of the motor in the second embodiment. A diagram showing the configuration of the core. A diagram showing the configuration of the core in modified example 2-1. A diagram showing the schematic configuration of the motor in the third embodiment. A diagram showing the configuration of the core. A diagram showing the configuration of the core in modified example 3-1.

[0015] Several embodiments for implementing this disclosure are described below with reference to the drawings. In each embodiment, parts corresponding to matters described in a preceding embodiment are denoted by the same reference numerals, and redundant explanations may be omitted. If only a part of the configuration is described in each embodiment, other parts of the configuration can be applied to other embodiments described in advance. Not only are combinations of parts that are explicitly shown to be combinable in each embodiment possible, but embodiments can also be partially combined even if not explicitly shown, as long as there are no particular problems with the combination.

[0016] <First Embodiment> The propulsion system 30 shown in Figure 1 is mounted on the eVTOL 10. The eVTOL 10 is an electric vertical take-off and landing aircraft. An electric vertical take-off and landing aircraft is an electric vertical take-off and landing aircraft that is capable of vertical take-off and landing. eVTOL is an abbreviation for electric Vertical Take-Off and Landing aircraft. The eVTOL 10 is an electric flying vehicle that flies in the atmosphere and is sometimes referred to as an electric flying vehicle. The eVTOL 10 is also an electric aircraft and is sometimes referred to as an electric aircraft. The eVTOL 10 is a manned flying vehicle that carries a crew. The crew of the eVTOL 10 includes a pilot as the operator or driver. The propulsion system 30 is a system that drives the eVTOL 10 to fly. The propulsion system 30 is sometimes referred to as a flight system.

[0017] The eVTOL 10 has an airframe 11 and a propeller 20. The airframe 11 has an airframe body 12 and wings 13. The airframe body 12 is the fuselage of the airframe 11 and has a shape that extends, for example, forward and backward. The wings 13 extend from the airframe body 12 and are provided in multiples on the airframe body 12. The wings 13 are fixed wings. The multiple wings 13 include main wings, tail wings, etc.

[0018] The eVTOL 10 has an aircraft cabin. The aircraft cabin is located inside the eVTOL 10. For example, the aircraft cabin is the internal space of the aircraft body 12 and is formed by the aircraft body 12. The aircraft cabin may include a crew compartment 14 or a cargo compartment. The crew compartment 14 may include a passenger cabin or a pilot's cabin. The crew compartment 14 is equipped with seats for the crew. The crew compartment 14 does not have to be occupied by crew members and may contain cargo.

[0019] Multiple propellers 20 are provided on the airframe 11. The eVTOL 10 is a multirotor having at least three propellers 20. For example, at least four propellers 20 are provided on the airframe 11. The propellers 20 are provided on the airframe body 12 and the wings 13, respectively. The propellers 20 rotate around their propeller axis. The propeller axis is, for example, the center line of the propeller 20. The propellers 20 can generate thrust and lift in the eVTOL 10. The propellers 20 are also sometimes referred to as rotors or rotor blades.

[0020] The propeller 20 has blades 21 and a boss 22. Multiple blades 21 are arranged in the circumferential direction of the propeller axis. The boss 22 connects the multiple blades 21. The blades 21 extend radially from the boss 22 along the propeller axis. The propeller 20 has a propeller shaft (not shown). The propeller shaft is the axis of rotation of the propeller 20 and extends from the boss 22 along the propeller axis.

[0021] The eVTOL 10 is a tiltrotor aircraft. In the eVTOL 10, the tilt angle of the propeller 20 is adjustable. However, the eVTOL 10 does not have to be a tiltrotor aircraft. For example, the eVTOL 10 may have separate propellers 20 for lift and propellers 20 for cruising.

[0022] The eVTOL 10 includes a battery 31, a distributor 32, a flight control device 40, and an EPU 50. The battery 31, distributor 32, flight control device 40, and EPU 50 are included in the propulsion system 30. The battery 31 is connected to multiple EPUs 50 so as to be energized. The battery 31 is a power supply unit that supplies power to the EPUs 50 and corresponds to a power supply unit. The battery 31 is a DC voltage source that applies a DC voltage to the EPUs 50. The battery 31 has a rechargeable secondary battery. The battery 31 also supplies power to the flight control device 40. In addition to the battery 31, a fuel cell or a generator may be used as a power supply unit.

[0023] The distributor 32 is electrically connected to the battery 31 and the multiple EPUs 50. The distributor 32 distributes power from the battery 31 to the multiple EPUs 50. The power that the distributor 32 distributes to the EPUs 50 is the drive power required to operate the EPUs 50.

[0024] The flight control device 40 controls the propulsion system 30. The flight control device 40 performs flight control to fly the eVTOL 10. The flight control device 40 is communicatively connected to multiple EPUs 50. The flight control device 40 controls the multiple EPUs 50 individually. The flight control device 40 controls the EPUs 50 via a control circuit 160, which will be described later. The flight control device 40 controls the control circuit 160.

[0025] The EPU 50 is a device that drives the propeller 20 to rotate, and is equivalent to a drive unit. EPU is an abbreviation for Electric Propulsion Unit. The EPU 50 is sometimes referred to as an electric drive unit or electric drive system. An EPU 50 is provided individually for each of the multiple propellers 20. The EPU 50s are arranged along the propeller axis of the propeller 20. All of the multiple EPU 50s are fixed to the aircraft body 11. The EPU 50 rotatably supports the propeller 20. The EPU 50 is connected to the propeller 20. The propeller 20 is fixed to the aircraft body 11 via the EPU 50. When the tilt angle of the propeller 20 is changed, the angle of the EPU 50 is also changed.

[0026] The eVTOL 10 has a propulsion system 15. The propulsion system 15 is a device for propelling the eVTOL 10. The eVTOL 10 can perform lifts and other forms of flight by being propelled by the propulsion system 15. The propulsion system 15 has a propeller 20 and an EPU 50. In the propulsion system 15, the propeller 20 rotates in conjunction with the drive of the EPU 50. The propeller 20 corresponds to a rotating body. The eVTOL 10 flies by the rotation of the propeller 20. That is, the eVTOL 10 moves by the rotation of the propeller 20. The eVTOL 10 corresponds to a moving body.

[0027] As shown in Figures 1 and 2, the EPU 50 has a motor unit 60 and an inverter unit 80. The motor unit 60 has a motor 61. The motor unit 60 corresponds to a rotating electric machine. The inverter unit 80 has an inverter 81. The motor 61 is electrically connected to the battery 31 via the inverter 81. The motor 61 is driven according to the power supplied from the battery 31 via the inverter 81.

[0028] Motor 61 is a multi-phase AC motor. Motor 61 is, for example, a three-phase AC motor and has U-phase, V-phase, and W-phase. Motor 61 is a power source for moving a moving object and functions as an electric motor. For example, a brushless motor is used as motor 61. Motor 61 functions as a generator during regeneration. Motor 61 has multiple-phase coils 64. The coils 64 are windings and form the armature. Motor 61 is driven by energizing the coils 64. Coils 64 are provided for each of the U-phase, V-phase, and W-phase. For example, motor 61 has a U-phase coil 64, a V-phase coil 64, and a W-phase coil 64. In motor 61, the multiple-phase coils 64 are connected to each other at a neutral point 65. Note that the U-phase is sometimes referred to as the first phase, the V-phase as the second phase, and the W-phase as the third phase.

[0029] In Figure 2, the inverter 81 drives the motor 61 by converting the power supplied to the motor 61. The inverter 81 converts the power supplied to the motor 61 from DC to AC. The inverter 81 is a power conversion unit that converts power. The inverter 81 is a multi-phase power conversion unit and performs power conversion for each of the multiple phases. For example, the inverter 81 is a three-phase inverter and performs power conversion for each of the U-phase, V-phase, and W-phase. The inverter device 80 is sometimes referred to as a power conversion device.

[0030] The inverter device 80 has a P line 141 and an N line 142. The P line 141 and the N line 142 electrically connect the battery 31 and the inverter 81. The P line 141 is electrically connected to the positive electrode of the battery 31. The N line 142 is electrically connected to the negative electrode of the battery 31. In the battery 31, the positive electrode is the electrode on the high potential side, and the negative electrode is the electrode on the low potential side. The P line 141 and the N line 142 are power lines for supplying power. The P line 141 is the power line on the high potential side and is sometimes referred to as the high potential line. The N line 142 is the power line on the low potential side and is sometimes referred to as the low potential line.

[0031] The EPU 50 has an output line 143. The output line 143 is a power line for supplying power to the motor 61. The output line 143 electrically connects the motor 61 and the inverter 81. The output line 143 is connected to the motor device 60 and the inverter device 80.

[0032] The inverter device 80 has a smoothing capacitor 145. The smoothing capacitor 145 is a capacitor that smooths the DC voltage supplied from the battery 31. The smoothing capacitor 145 is connected to the P line 141 and the N line 142 between the battery 31 and the inverter 81. The smoothing capacitor 145 is connected in parallel to the inverter 81.

[0033] The inverter 81 is a power conversion circuit, for example, a DC-AC conversion circuit. The inverter 81 has upper and lower arm circuits 85 for multiple phases. For example, the inverter 81 has upper and lower arm circuits 85 for each of the U-phase, V-phase, and W-phase. The upper and lower arm circuits 85 have an upper arm 85a and a lower arm 85b. The upper arm 85a and the lower arm 85b are connected in series to the battery 31. The upper arm 85a is connected to the P line 141, and the lower arm 85b is connected to the N line 142.

[0034] The output line 143 is connected to the upper and lower arm circuit 85 for each of the multiple phases. The output line 143 is connected between the upper arm 85a and the lower arm 85b. In each of the multiple phases, the output line 143 connects the upper and lower arm circuit 85 to the coil 64. The output line 143 is connected to the coil 64 on the opposite side from the neutral point 65.

[0035] The upper arm 85a and the lower arm 85b have an arm switch 86 and a diode 87. The arm switch 86 is a transistor such as a MOSFET. MOSFET is an abbreviation for Metal-Oxide-Semiconductor Field-Effect Transistor. The arm switch 86 is a switching element and is capable of converting power by switching. The switching element can be any semiconductor element such as a power element. The arm switch 86 is a conversion switch for converting power.

[0036] The EPU 50 has a control circuit 160. The control circuit 160 is included in the inverter device 80. The control circuit 160 controls the drive of the inverter 81. The control circuit 160 controls the drive of the motor 61 via the inverter 81. The control circuit 160 is sometimes referred to as the motor control unit. In Figure 2, the control circuit 160 is shown as CD.

[0037] As shown in Figure 3, in the EPU 50, the motor unit 60 and the inverter unit 80 are arranged in the axial direction AD along the motor axis Cm. The motor unit 60 is located between the propeller 20 and the inverter unit 80 in the axial direction AD. The motor axis Cm is the centerline of the motor 61 and is a hypothetical line extending in a straight line. The motor axis Cm corresponds to the axis of rotation. The axial direction AD is the direction in which the motor axis Cm extends.

[0038] Regarding the motor axis Cm, the axial direction AD, circumferential direction CD, and radial direction RD are mutually orthogonal. The circumferential direction CD is the rotation direction of the motor 61. The radial direction RD is sometimes referred to as the radial outer side or outer circumference, and the inner side as the radial inner side or inner circumference. The axial direction AD is sometimes referred to as the axial direction.

[0039] The EPU 50 has a motor housing 70 and an inverter housing 90. The motor housing 70 is included in the motor unit 60. The motor housing 70 houses the motor 61. The inverter housing 90 is included in the inverter unit 80. The inverter housing 90 houses the inverter 81. The motor housing 70 and the inverter housing 90 are connected to each other.

[0040] As shown in Figure 4, the motor housing 70 has a motor outer circumferential wall 71, a rear frame 370, and a drive frame 390. The motor outer circumferential wall 71 and the frames 370 and 390 are made of a metal or the like and have thermal conductivity. The motor outer circumferential wall 71 is formed in a cylindrical shape and extends in the axial direction A. The frames 370 and 390 are formed in a plate shape and extend in a direction perpendicular to the axial direction A. The rear frame 370 and the drive frame 390 are arranged in the axial direction A via the motor outer circumferential wall 71. The frames 370 and 390 are fixed to the motor outer circumferential wall 71 by fasteners such as bolts. Figure 4 also shows a longitudinal cross-section of the motor device 60 cut along the motor axis Cm.

[0041] The motor housing 70 has an outer circumferential surface 70a and an inner circumferential surface 70b. The outer circumferential surface 70a is the outer circumferential surface of the motor housing 70 and is included in the outer surface of the motor housing 70. The inner circumferential surface 70b is the inner circumferential surface of the motor housing 70 and is included in the inner surface of the motor housing 70. The outer circumferential surface 70a and the inner circumferential surface 70b are formed by the motor outer circumferential wall 71.

[0042] The rear frame 370 covers the inner space of the motor outer periphery wall 71 from the inverter device 80 side. The rear frame 370 is located on the side opposite to the propeller 20 via the motor outer periphery wall 71. The drive frame 390 covers the inner space of the motor outer periphery wall 71 from the side opposite to the inverter device 80. The drive frame 390 is located on the propeller 20 side of the motor outer periphery wall 71.

[0043] The motor housing 70 has a motor fin 72. The motor fin 72 is provided on the outer surface of the motor housing 70. For example, the motor fin 72 is provided on the outer peripheral surface 70a of the housing. The motor fin 72 protrudes outward from the outer peripheral wall 71 of the motor. The motor fin 72 extends in a direction orthogonal to the circumferential direction CD. A plurality of motor fins 72 are arranged in the circumferential direction CD. The motor fin 72 is a heat radiating fin that releases the heat of the motor device 60 to the outside.

[0044] The motor 61 has a stator 200, a rotor 300, and a shaft 340. The stator 200 is a stator. The stator 200 has a coil 64. The rotor 300 is a rotor. The rotor 300 rotates relative to the stator 200. The rotor 300 rotates about the motor axis Cm. The motor axis Cm is the center line of the rotor 300. The stator 200 extends annularly in the circumferential direction CD. The motor axis Cm coincides with the center line of the stator 200.

[0045] The motor device 60 is an axial gap type rotating electric machine. The motor 61 is an axial gap type motor. In the motor 61, the stator 200 and the rotor 300 are arranged in the axial direction AD via a gap 305. The motor device 60 is a double rotor type rotating electric machine. The motor 61 is a double rotor type motor. The motor 61 has two rotors 300, namely a first rotor 300A and a second rotor 300B. The first rotor 300A and the second rotor 300B are arranged in the axial direction AD via the stator 200. The motor 61 may be referred to as a double axial motor. In an axial gap type motor, the axial direction AD corresponds to the first direction, and the radial direction RD corresponds to the second direction.

[0046] The shaft 340 supports the rotor 300. The shaft 340 rotates about the motor axis Cm together with the rotor 300. The center line of the shaft 340 coincides with the motor axis Cm. The shaft 340 connects the rotor 300 and the propeller 20.

[0047] The shaft 340 is rotatably supported by a rear bearing 350 and a drive bearing 360. The bearings 350 and 360 are included in the motor device 60. The bearings 350 and 360 extend annularly in the circumferential direction CD. The rear bearing 350 and the drive bearing 360 are arranged axially in the axial direction AD via the rotor 300. The bearings 350 and 360 are fixed to the motor housing 70. The rear bearing 350 is fixed to the rear frame 370. The drive bearing 360 is fixed to the drive frame 390.

[0048] The motor housing 70 houses the stator 200 and the rotor 300. In the motor housing 70, the motor outer peripheral wall 71 covers the stator 200 and the rotor 300 from the outer peripheral side. The motor housing 70 corresponds to the electric machine housing. The motor outer peripheral wall 71 corresponds to the electric machine outer peripheral wall.

[0049] The rotor 300 has a magnet portion 310 and a magnet holder 320. A plurality of magnet portions 310 are arranged in the circumferential direction CD in each of the rotors 300. The magnet portion 310 is configured to include permanent magnets and forms a field magnet. In the rotor 300, the magnet portion 310 generates magnetic flux. The magnet portion 310 of the first rotor 300A and the magnet portion 310 of the second rotor 300B are arranged axially in the axial direction AD via the stator 200. The magnet holder 320 supports the magnet portion 310. The magnet holder 320 forms the outer peripheral end and the inner peripheral end of the rotor 300.

[0050] The stator 200 has a coil section 211 and a core 230. The coil section 211 is formed including a coil wire 211a. The coil wire 211a forms the coil section 211 when wound around the core 230. The coil wire 211a is an electric wire such as a flat rectangular wire. The coil section 211 and the coil wire 211a are electrically conductive. The coil section 211 is attached to the core 230. The coil section 211 is formed in a cylindrical shape as a whole and extends in the axial direction A and D. The core 230 is an iron core and extends in the axial direction A and D. The core 230 corresponds to the stator core. Multiple coil sections 211 and cores 230 are arranged in the circumferential direction CD along the inner circumferential surface 70b of the housing. In the stator 200, a coil 64 is formed by multiple coil sections 211.

[0051] The stator 200 has a core piece 210. The core piece 210 is formed including a coil portion 211 and a core 230. The core piece 210 is a component in which the coil portion 211 and the core 230 are integrated. The core piece 210 is sometimes referred to as a coil piece. In the stator 200, multiple core pieces 210 are arranged in the circumferential direction CD, so that multiple coil portions 211 are arranged in the circumferential direction CD.

[0052] The coil portion 211 is wound around the core 230 via a bobbin 240. The bobbin 240 is included in the core piece 210. The core piece 210 is a component in which the coil portion 211, the core 230, and the bobbin 240 are integrated. The bobbin 240 is made of a resin material or the like and has electrical insulating properties. The bobbin 240 is formed in a cylindrical shape as a whole and extends in the axial direction A and D. The bobbin 240 accommodates at least a portion of the core 230 so as to cover the outer circumferential surface of the core 230.

[0053] The core piece 210 has a piece cover 255 (see Figure 20). The piece cover 255 is made of a resin material or the like and has electrical insulating properties. The piece cover 255 is provided to cover the coil section 211, the core 230, and the bobbin 240. The piece cover 255 protects the coil section 211, the core 230, and the bobbin 240. In Figure 4 and other figures, the piece cover 255 is not shown.

[0054] As shown in Figures 4 and 5, the motor device 60 has a core piece support section 280. The core piece support section 280 supports the core piece 210. The core piece support section 280 is fixed to the outer peripheral wall 71 of the motor. The core piece support section 280 has a first support plate 281A, a second support plate 281B, and a support pole 291.

[0055] As shown in Figures 4 and 5, the support plates 281A and 281B are formed in a plate shape and extend in a direction perpendicular to the axial direction AD. The first support plate 281A and the second support plate 281B are aligned in the axial direction AD via a core piece 210. The core piece 210 is fixed to the motor housing 70 while sandwiched between the first support plate 281A and the second support plate 281B.

[0056] The support pole 291 shown in Figure 4 extends columnarly in the axial direction AD. The support pole 291 is provided radially inward of the core piece 210. The support pole 291 connects the first support plate 281A and the second support plate 281B. The support plates 281A and 281B are fixed to the wall projection 73 of the motor outer peripheral wall 71. As shown in Figures 4 and 6, the wall projection 73 is a projection provided on the inner circumferential surface 70b of the housing. The wall projection 73 connects the first support plate 281A and the second support plate 281B.

[0057] As shown in Figure 5, the support plates 281A and 281B have core holes 285a. The core holes 285a penetrate the support plates 281A and 281B in the axial direction AD. Multiple core holes 285a are arranged in the circumferential direction CD. The core piece 210 is fitted into the core holes 285a. A portion of the core 230 is exposed to the rotor 300 side through the core holes 285a. In the core 230, the flange 235, which will be described later, is fitted into the core holes 285a.

[0058] As shown in Figures 7, 8, and 9, the core 230 has a core-facing surface 230a. The core-facing surface 230a is included in the outer surface of the core 230. The core-facing surface 230a is the end face of the core 230. The core-facing surface 230a extends in a direction perpendicular to the axial direction AD. The core-facing surface 230a faces the rotor 300 via a gap 305. For example, when the core 230 and the magnet portion 310 are aligned in the axial direction AD, the core-facing surface 230a faces the magnet portion 310. A pair of core-facing surfaces 230a are arranged in the axial direction AD. One of the pair of core-facing surfaces 230a faces the first rotor 300A, and the other faces the second rotor 300B.

[0059] As shown in Figure 10, the core 230 has teeth 231 and a flange 235. The teeth 231 and the flange 235 are independent components. The teeth 231 and the flange 235 are fixed to each other by adhesive or the like. The teeth 231 and the flange 235 are arranged in the axial direction AD. The axial direction AD corresponds to one direction. The flange 235 is provided on the rotor 300 side of the teeth 231. That is, the flange 235 is provided between the teeth 231 and the rotor 300.

[0060] The teeth 231 are formed in a columnar shape and extend in the axial direction AD. The flanges 235 are formed in a plate shape and extend in a direction perpendicular to the axial direction AD. The flanges 235 are arranged in pairs via the teeth 231. The teeth 231 extend in the axial direction AD so as to span across the pair of flanges 235. Of the pair of flanges 235, one faces the first rotor 300A and the other faces the second rotor 300B. The flanges 235 form the core-facing surface 230a. The flanges 235 are the portions of the core 230 that face the gap 305. At least a portion of the flanges 235 protrudes from the teeth 231 in a direction perpendicular to the axial direction AD. For example, the flanges 235 protrude from the teeth 231 in the circumferential direction CD.

[0061] In the core 230, the teeth 231 are housed inside the coil portion 211, while the flange 235 is not housed inside the coil portion 211. The teeth 231 do not protrude further towards the rotor 300 than the coil portion 211. The flange 235 does not extend inside the coil portion 211. The boundary between the teeth 231 and the coil portion 211 is located at the end of the coil portion 211, aligned in the circumferential direction CD and the radial direction RD.

[0062] As shown in Figures 10 and 15, the tooth 231 has a tooth end face 231a and a tooth outer circumferential surface 231b. The tooth end face 231a and the tooth outer circumferential surface 231b are included in the outer surface of the tooth 231. The tooth end face 231a is the end face of the tooth 231. The tooth end face 231a extends in a direction perpendicular to the axial direction AD. The tooth outer circumferential surface 231b is the outer circumferential surface of the tooth 231. The tooth outer circumferential surface 231b extends in the axial direction AD so as to span across the pair of tooth end faces 231a.

[0063] As shown in Figures 10 and 17, the flange 235 has a first flange surface 235a and a second flange surface 235b. The flange surfaces 235a and 235b are plate surfaces of the flange 235 and extend in a direction perpendicular to the axial direction AD. In the flange 235, one of a pair of plate surfaces is the first flange surface 235a and the other is the second flange surface 235b. The first flange surface 235a faces the first rotor 300A, and the second flange surface 235b faces the second rotor 300B. The flange surfaces 235a and 235b are included in the core-facing surface 230a.

[0064] As shown in Figure 11, the teeth 231 and the flange 235 are bonded together by the core bonding portion 250. The core bonding portion 250 is contained within the core 230. The core bonding portion 250 is provided between the teeth 231 and the flange 235. The core bonding portion 250 is formed when the core adhesive material 251 (see Figure 17) solidifies. The core bonding portion 250 is made of a resin material or the like. The core bonding portion 250 has electrical insulating properties. The core bonding portion 250 corresponds to the bonding portion.

[0065] As shown in Figures 10 and 11, the teeth 231 are formed by including a plurality of magnetic plate materials 232. The plurality of magnetic plate materials 232 are fixed to each other in a stacked state. The magnetic plate materials 232 are formed in a plate shape. The teeth 231 are sometimes referred to as a stacked core. The plurality of magnetic plate materials 232 are arranged in the radial direction RD. The plurality of magnetic plate materials 232 are bonded to each other by a plate bonding portion 233. The plate bonding portion 233 is formed of a resin material or the like and has electrical insulating properties. The plate bonding portion 233 is included in the teeth 231. The teeth 231 corresponds to the first core member, and the magnetic plate materials 232 correspond to the first member.

[0066] The magnetic plate material 232 is formed by including a soft magnetic material. For example, the magnetic plate material 232 is formed by including an electrical steel sheet or an amorphous material. In a configuration in which the magnetic plate material 232 is formed by including an electrical steel sheet, the teeth 231 are sometimes referred to as laminated electrical steel sheets. In a configuration in which the magnetic plate material 232 is formed by including an amorphous material, the teeth 231 are sometimes referred to as laminated amorphous material. For example, in a magnetic plate material 232 formed by including an amorphous material, there is no crystalline structure.

[0067] As shown in Figure 11, the flange 235 is formed by including magnetic powder 236. The flange 235 is formed by applying pressure or sintering to the magnetic powder 236. For example, the flange 235 is formed by press-forming the magnetic powder 236. The flange 235 is sometimes referred to as a compacted powder core. In the flange 235, multiple magnetic powders 236 are aggregated together. Multiple magnetic powders 236 are joined to each other. In the flange 235, many magnetic powders 236 are joined via an insulating coating 237. The insulating coating 237 is formed from a resin material or the like and has electrical insulating properties. The insulating coating 237 is contained within the flange 235. The flange 235 corresponds to the second member, and the magnetic powder 236 corresponds to the second member.

[0068] The magnetic powder 236 is formed in powder form and contains a soft magnetic material. For example, the magnetic powder 236 is formed by containing iron powder or iron-based alloy powder. In a configuration where the magnetic powder 236 is formed by containing iron powder, the flange 235 is sometimes referred to as a compacted soft magnetic core. The magnetic powder 236 is a smaller component than the magnetic plate material 232. Note that in Figure 11, the hatching of the first component 232, the plate bonding portion 233, the second component 236, and the insulating coating 237 has been omitted.

[0069] As shown in Figures 7 to 9, the magnetic flux generated by the motor 61 includes a first magnetic flux M1 and a second magnetic flux M2. The first magnetic flux M1 extends in the axial direction AD so as to span between the stator 200 and the rotor 300. The first magnetic flux M1 extends from one of the first rotor 300A and the second rotor 300B through the core 230 toward the other. The first magnetic flux M1 is linked to the core 230 so as to extend along the surface of the magnetic plate material 232. The first magnetic flux M1 includes magnetic flux that extends outward from the magnet section 310 and magnetic flux that extends inward from the magnet section 310.

[0070] The second magnetic flux M2 extends along the gap 305 so as to intersect with the first magnetic flux M1. The second magnetic flux M2 passes through the core 230 in a direction perpendicular to the axial direction AD. For example, the second magnetic flux M2 links with the core 230 so as to extend in the radial direction RD. The second magnetic flux M2 includes leakage flux and short-circuit flux from the magnet section 310. The second magnetic flux M2 passes more easily through the core 230 in the part closer to the rotor 300. In the core 230, there is a greater amount of the second magnetic flux M2 passing through the flange 235 and less amount passing through the teeth 231.

[0071] In the stator 200, the first magnetic flux M1 passes through the core 230, which can cause a first eddy current Im1 to be generated in the core 230 (see Figure 12). In contrast, because multiple magnetic plate materials 232 form a laminated structure, the first eddy current Im1 is less likely to be generated in the teeth 231. In the teeth 231, the flow of the first eddy current Im1 in the radial direction RD is restricted by the plate bonding portion 233. Also, because the flange 235 is a compacted powder core, the first eddy current Im1 is less likely to be generated in the flange 235 as well. In the flange 235, the flow of the first eddy current Im1 in the radial direction RD and the circumferential direction CD is restricted by the insulating coating 237. In the core 230, eddy current loss caused by the first eddy current Im1 is reduced in both the teeth 231 and the flange 235. Eddy current loss is included in the iron loss generated in the motor 61.

[0072] In the stator 200, the second magnetic flux M2 passes through the core 230, which can cause a second eddy current Im2 to be generated in the core 230 (see Figure 13). In contrast, the flange 235 is less prone to the generation of a second eddy current Im2 because of the aggregate structure formed by numerous magnetic powders 236. In the flange 235, the insulating coating 237 restricts the flow of the second eddy current Im2 in the circumferential direction CD and the axial direction AD. In the flange 235, eddy current losses caused by the second eddy current Im2 are reduced.

[0073] In teeth 231, the magnetic plate material 232 extends in a direction perpendicular to the radial direction RD. Also, the second eddy current Im2 flows in a direction perpendicular to the radial direction RD. Therefore, if the second magnetic flux M2 were to pass through teeth 231 in the radial direction RD, the second eddy current Im2 would easily flow along the plate surface of the magnetic plate material 232. In contrast, as described above, in core 230, the flange 235 is positioned where the second magnetic flux M2 can easily pass through, and the teeth 231 are positioned where the second magnetic flux M2 cannot easily pass through. In this way, because the second magnetic flux M2 cannot easily pass through teeth 231, the eddy current loss caused by the second eddy current Im2 in teeth 231 tends to be sufficiently small.

[0074] Next, the manufacturing method of the motor device 60 will be described. The manufacturing process for the motor device 60 will be explained with reference to the flowchart in Figure 14. Steps P101 to P109 shown in Figure 14 are for manufacturing the core piece 210. Steps P101 to P107 are for manufacturing the core 230. The manufacturing method of the motor device 60 includes the manufacturing method of the core 230. The manufacturing method of the core 230 corresponds to the manufacturing method of the stator core.

[0075] In steps P101 to P103 shown in Figure 14, the worker prepares for manufacturing the core 230. In step P101, the worker prepares parts for manufacturing the core 230. For example, the worker prepares plate members for forming the magnetic plate material 232 as parts for manufacturing the teeth 231. The worker prepares powder for forming the magnetic powder 236 as parts for manufacturing the flange 235. For convenience of explanation, the plate members may be referred to as magnetic plate material 232 and the powder as magnetic powder 236.

[0076] Furthermore, the worker prepares parts and other materials for manufacturing the core piece 210. For example, the worker prepares wire components for forming the coil section 211 and the coil wire 211a. The worker also prepares resin materials for forming the piece cover 255. For the sake of explanation, the wire components may be referred to as the coil wire 211a.

[0077] In process P102, the worker manufactures the flange 235. The worker forms the flange 235 by pressing the magnetic powder 236. The worker prepares the flange 235 by performing processes P101 and P102. Processes P101 and P102 correspond to the second preparation process. The worker may also prepare a core member that can be used as the flange 235 in process P101. For the sake of explanation, the core member for forming the flange 235 may be referred to as the flange 235.

[0078] In process P103, the worker manufactures the teeth 231 (see Figure 15). The worker forms the teeth 231 by laminating magnetic plate material 232. The worker prepares the teeth 231 by performing processes P101 and P103. Processes P101 and P103 correspond to the first preparation process. The worker may also prepare a core member that can be used as the teeth 231 in process P101. For convenience of explanation, the core member for forming the teeth 231 may be referred to as the teeth 231.

[0079] In step P104, the worker forms the bobbin 240 (see Figure 16). The worker attaches the bobbin 240 to the teeth 231 using an insert mold or the like. The bobbin 240 is attached to the teeth 231 so as to cover the outer surface 231b of the teeth. The bobbin 240 corresponds to the covering portion. Step P104 corresponds to the covering process.

[0080] The bobbin 240 has a bobbin end face 240a and a bobbin outer circumferential surface 240b. The bobbin end face 240a is the end face of the bobbin 240. The bobbin outer circumferential surface 240b is the outer circumferential surface of the bobbin 240. The bobbin end faces 240a are arranged in pairs via the bobbin outer circumferential surface 240b. When the bobbin 240 is mounted on the teeth 231, the teeth end face 231a and the bobbin end face 240a are arranged side by side. The teeth end face 231a and the bobbin end face 240a form the same plane.

[0081] In steps P105 to P107, the worker fixes the teeth 231 and the flange 235. The worker fixes the flange 235 to both the teeth 231 and the bobbin 240. The worker fixes the tooth end face 231a and the bobbin end face 240a to the first flange face 235a. Steps P105 to P107 correspond to the fixing process.

[0082] In process P105, the worker polishes the teeth 231 and the flange 235. The worker polishes at least one of the tooth end face 231a and the first flange face 235a. For example, the worker polishes the tooth end face 231a. The tooth end face 231a is a fixing surface for fixing the tooth 231 to the flange 235. The tooth end face 231a corresponds to the first fixing surface. The first flange face 235a is a fixing surface for fixing the flange 235 to the tooth 231. The first flange face 235a is also an adhesive surface for bonding the flange 235 to the tooth 231. The first flange face 235a corresponds to the second fixing surface and adhesive surface. Process P105 corresponds to the polishing process.

[0083] The worker may inspect the bobbin 240 after polishing the teeth 231 and flange 235. For example, the worker may check that the electrical insulation of the bobbin 240 is appropriate. The worker may also check that the shape and size of the bobbin 240 are appropriate.

[0084] In step P106, the worker applies core adhesive 251 to the teeth 231, bobbin 240, and flange 235 (see Figure 17). Core adhesive 251 is an adhesive in a molten state. Core adhesive 251 is formed by including a thermosetting molten resin or a room-temperature curing molten resin. The worker applies core adhesive 251 to at least one of the tooth end face 231a, bobbin end face 240a, and first flange face 235a. For example, the worker applies core adhesive 251 so that it covers both the tooth end face 231a and the bobbin end face 240a. The bobbin end face 240a is a fixing surface for fixing the bobbin 240 to the flange 235. The bobbin end face 240a corresponds to the coating fixing surface. Step P106 corresponds to the application step.

[0085] In step P107, the worker adheres the tooth end face 231a and the bobbin end face 240a to the first flange face 235a using the core adhesive 251. The worker assembles the flange 235 to the teeth 231 and bobbin 240 so that the first flange face 235a overlaps both the tooth end face 231a and the bobbin end face 240a. The worker forms the core adhesive portion 250 by solidifying the core adhesive 251 by heating or other means. Step P107 corresponds to the bonding process. The worker manufactures the core 230 with the bobbin 240 attached by fixing the teeth 231 and the flange 235 (see Figure 18).

[0086] After manufacturing the core 230, the worker may inspect the core 230. For example, the worker may confirm that the magnetic flux passes through the core 230 properly. The worker may also inspect the loss conditions in the core 230. For example, the worker may measure the eddy current loss occurring in the core 230 and confirm that the eddy current loss is within the acceptable range.

[0087] In step P108, the worker forms the coil portion 211 by winding the coil wire 211a around the bobbin 240 and core 230 (see Figure 19). After forming the coil portion 211, the worker may inspect the core 230, bobbin 240, and coil portion 211. For example, the worker confirms that proper electrical insulation is ensured between the core 230 and the coil 64.

[0088] In step P109, the worker forms a piece cover 255 so as to cover the coil wire 211a, core 230, and bobbin 240. The worker manufactures the core piece 210 by attaching the piece cover 255 to the coil wire 211a, core 230, and bobbin 240 using an insert mold or the like (see Figure 20). After forming the piece cover 255, the worker may inspect the piece cover 255. For example, the worker may confirm that the electrical insulation of the piece cover 255 is properly ensured.

[0089] In this embodiment described above, the teeth 231 have a laminated structure formed by a plurality of magnetic plate materials 232. The flange 235 has an aggregate structure formed by a plurality of magnetic powders 236. Since the core 230 has teeth 231 and flange 235, the aggregate structure of the flange 235 can suppress the generation of the first eddy current Im1 in the first magnetic flux M1 that passes in a direction in which the first eddy current Im1 is likely to be generated, even in the laminated structure of teeth 231. As a result, losses such as eddy current losses can be reduced in the core 230.

[0090] In the core 230, eddy current losses can be effectively suppressed by using different materials and components for the teeth 231 and the flange 235. In the motor 61, a laminated structure that is highly effective in reducing losses for the first magnetic flux M1 is provided to the teeth 231, and a composite structure that is highly effective in reducing losses for the second magnetic flux M2 is provided to the flange 235, thereby allowing the laminated structure and composite structure to be placed in the core 230 in the most appropriate locations. For example, the teeth 231 are provided with a laminated structure that has anisotropy with respect to the eddy current suppression effect. On the other hand, the flange 235, which does not exhibit an eddy current suppression effect easily due to the anisotropy of the laminated structure, is provided with a composite structure that does not have anisotropy with respect to the eddy current suppression effect. In the core 230, the appropriate material is placed in the appropriate location depending on the presence or absence of anisotropy.

[0091] Between a laminated structure and an aggregated structure, the aggregated structure offers a higher eddy current suppression effect, while the laminated structure allows for greater strength to be imparted to the core 230. Therefore, for example, in a configuration where the core 230 is formed using only the aggregated structure, while the eddy current suppression effect can be improved, there is a concern that the strength of the core 230 may be insufficient. Similarly, in a configuration where the core 230 is formed using only the laminated structure, while the strength of the core 230 can be improved, there is a concern that the eddy current suppression effect may be insufficient. In contrast, in this embodiment, the core 230 is a hybrid core having both a laminated structure and an aggregated structure, thereby achieving a good balance between the eddy current suppression effect and the strength of the core 230.

[0092] According to this embodiment, the flange 235 is formed by joining a plurality of magnetic powders 236 together. Therefore, even if multiple magnetic fluxes extending in different directions pass through the flange 235, it is possible to exert an eddy current suppression effect for each of the multiple magnetic fluxes. For example, the flange 235 can exert both the effect of suppressing the generation of a first eddy current Im1 due to a first magnetic flux M1, and the effect of suppressing the generation of a second eddy current Im2 due to a second magnetic flux M2.

[0093] In this embodiment, the teeth 231 and the flange 235 are arranged in a single direction, the axial direction A and D. In this configuration, the flange 235 is positioned in a location where the stacked structure of the teeth 231 is less likely to exert an eddy current suppression effect, while there is no need to position the flange 235 in a location where the stacked structure of the teeth 231 is more likely to exert an eddy current suppression effect. In this way, the arrangement of the flange 235 cluster structure can be done without excess or deficiency, thereby reducing the burden and cost of manufacturing the core 230.

[0094] In this embodiment, the teeth 231 and the flange 235 are bonded together by the core bonding portion 250. In this configuration, the teeth 231 and the flange 235 can be manufactured as separate components. This increases the degree of freedom regarding the laminated structure of the teeth 231 and the assembled structure of the flange 235. As a result, the teeth 231 and the flange 235 can be formed to enhance the eddy current suppression effect. Furthermore, in this configuration, the burden of integrating the teeth 231 and the flange 235 during the manufacturing of the core 230 can be reduced by the core bonding portion 250.

[0095] In this embodiment, the tooth end face 231a and the bobbin end face 240a and the first flange face 235a are bonded together by the core bonding portion 250. This configuration allows for a setup in which the tooth 231 and the bobbin 240 and the flange 235 are fixed together by the core bonding portion 250. Furthermore, in this configuration, the area indirectly bonded between the tooth 231 and the flange 235 increases by the area bonded between the bobbin end face 240a and the first flange face 235a. Therefore, the fixing strength between the tooth 231 and the flange 235 can be increased.

[0096] In this embodiment, the motor 61 has a stator 200 and a rotor 300 arranged in the axial direction AD. In this configuration, the first magnetic flux M1 easily passes through the core 230 in the axial direction AD, and the second magnetic flux M2 easily passes through the core 230 in the radial direction RD. Therefore, the fact that the teeth 231 have a stacked structure and the flange 235 have a clustered structure allows the core 230 to be provided with a suppression effect on both the first eddy current Im1 caused by the first magnetic flux M1 and the second eddy current Im2 caused by the second magnetic flux M2.

[0097] In this embodiment, the stacked structure of the teeth 231 is positioned on the rotor 300 in the axial direction AD to restrict the generation of a first eddy current Im1 in the core 230 due to the first magnetic flux M1. Therefore, the stacked structure of the teeth 231 can exert a suppression effect on the first eddy current Im1. Furthermore, the aggregate structure of the flanges 235 is provided between the teeth 231 and the rotor 300 in the axial direction AD to restrict the generation of a second eddy current Im2 in the core 230 due to the second magnetic flux M2. Therefore, the aggregate structure of the flanges 235 can exert a suppression effect on the second eddy current Im2.

[0098] In this embodiment, the flange 235 forms the core-facing surface 230a. The second magnetic flux M2 tends to pass radially RD through the core 230 at a position close to the core-facing surface 230a. Therefore, by arranging the flange 235 aggregate structure at a position through which the second magnetic flux M2 easily passes, a configuration can be achieved in which the flange 235 aggregate structure can easily exert a suppression effect on the second eddy current Im2.

[0099] According to this embodiment, the worker can manufacture the core 230 by fixing the teeth 231 and the flange 235 in the manufacturing process of the core 230. In this way, by manufacturing the teeth 231 and the flange 235 separately and then fixing them, two types of structures, a laminated structure of teeth 231 and an assembled structure of flange 235, can be given to the core 230.

[0100] According to this embodiment, the worker can increase the fixing strength between the tooth end face 231a and the first flange surface 235a by the core adhesive 251 by polishing at least one of the tooth end face 231a and the first flange surface 235a. This prevents insufficient fixing strength between the tooth 231 and the flange 235, even if the worker manufactures the tooth 231 and the flange 235 separately.

[0101] According to this embodiment, in addition to bonding the tooth end face 231a to the first flange face 235a, the worker also bonds the bobbin end face 240a to the first flange face 235a. This indirectly increases the bonding area between the tooth 231 and the flange 235 by the bobbin 240. Therefore, the fixing of the tooth 231 and the flange 235 can be reinforced by the bobbin 240.

[0102] In this embodiment, as a modification 1-1, the teeth 231 may protrude from the coil portion 211 in the axial direction AD, as shown in Figure 21. In this configuration, the flange 235 is provided at a position away from the coil portion 211 toward the rotor 300. Furthermore, the teeth 231 may protrude from the coil portion 211 in the axial direction AD on at least one of the first rotor 300A side and the second rotor 300B side. For example, the teeth 231 may protrude from the coil portion 211 toward the first rotor 300A side, but not toward the second rotor 300B side.

[0103] In this embodiment, as a modification 1-2, as shown in Figure 22, a part of the flange 235 may extend inside the coil portion 211. In this configuration, the teeth 231 are provided at a position away from the end of the coil portion 211 in the axial direction AD. Also, a part of at least one of the pair of flanges 235 may extend inside the coil portion 211. For example, of the pair of flanges 235, the flange 235 on the first rotor 300A side may extend inside the coil portion 211, while the flange 235 on the second rotor 300B side may not extend inside the coil portion 211.

[0104] <Second Embodiment> In the first embodiment described above, the motor 61 is a double-rotor type motor. In contrast, in the second embodiment, the motor 61 does not have to be a double-rotor type motor. Configurations, operations, and effects not specifically described in the second embodiment are the same as in the first embodiment described above. The second embodiment will be described mainly in terms of the differences from the first embodiment described above.

[0105] As shown in Figure 23, the motor device 60 is a single-rotor type rotating electric machine. Alternatively, the motor device 60 is a double-stator type rotating electric machine. The motor 61 has two stators 200, a first stator 200A and a second stator 200B. The first stator 200A and the second stator 200B are arranged in the axial direction AD via a rotor 300.

[0106] In this embodiment, the stator 200 has a core 430. The core 430 has a back core 431 and an inner core 435. The back core 431 extends annularly in the circumferential direction CD. The back core 431 extends in the circumferential direction CD so as to span across a plurality of coil portions 211. The back core 431 is located on the opposite side of the rotor 300 in the axial direction AD via the coil portions 211.

[0107] The inner core 435 extends axially AD from the back core 431 toward the rotor 300. Multiple inner cores 435 are arranged in the circumferential direction CD. A coil portion 211 is attached to the inner core 435. The coil portion 211 is wound around the inner core 435.

[0108] In the core 430, the back core 431 has a laminated structure, and the inner core 435 has an aggregated structure. As shown in Figure 24, the back core 431 has a plurality of magnetic plate materials 232, similar to the teeth 231 of the first embodiment. In the back core 431, the plurality of magnetic plate materials 232 are laminated in the radial direction RD. The magnetic plate materials 232 extend in a direction perpendicular to the radial direction RD. The back core 431 corresponds to the first core member. The inner core 435 has magnetic powder 236, similar to the flange 235 of the first embodiment. In the inner core 435, the aggregated plurality of magnetic powders 236 are joined to each other. The inner core 435 corresponds to the second core member.

[0109] In core 430, the inner core 435 is housed inside the coil portion 211, while the back core 431 is not housed inside the coil portion 211. The inner core 435 does not protrude axially AD from the coil portion 211 on either the rotor 300 side or the back core 431 side. The back core 431 does not extend inside the coil portion 211. The boundary between the back core 431 and the inner core 435 is located at the end of the coil portion 211, aligned circumferentially CD and radially RD.

[0110] In this embodiment, as a modification 2-1, as shown in Figure 25, at least a portion of the back core 431 may extend inside the coil portion 211. In this configuration, the protruding portion of the back core 431 extends inside the coil portion 211. The protruding portion extends axially AD from the back core 431 toward the rotor 300.

[0111] Furthermore, in this embodiment, the inner core 435 may protrude from the coil portion 211 in the axial direction AD. For example, the inner core 435 may protrude from the coil portion 211 toward the rotor 300 side, or it may protrude from the coil portion 211 toward the back core 431 side.

[0112] <Third Embodiment> In the first embodiment described above, the motor 61 is an axial gap type motor. In contrast, in the second embodiment, the motor 61 does not have to be an axial gap type motor. Configurations, operations, and effects not specifically described in the third embodiment are the same as in the first embodiment described above. In this third embodiment, the differences from the first embodiment described above will be explained in detail.

[0113] As shown in Figure 26, the motor device 60 is a radial gap type rotating electric machine. In a radial gap type rotating electric machine, the stator 200 and the rotor 300 are arranged radially RD with a gap 305 between them. For example, the stator 200 is located on the outer circumference side of the rotor 300.

[0114] The stator 200 has a core 530. The core 530 has a back core 531 and an inner core 535. The back core 531 extends in an annular shape in the circumferential direction CD. The back core 531 extends in the circumferential direction CD so as to span across a plurality of coil sections 211. The back core 531 is provided on the outer circumference side of the coil sections 211. The inner core 535 and the back core 531 are arranged in the radial direction RD. In this embodiment, the radial direction RD corresponds to one direction.

[0115] The inner core 535 extends radially RD from the back core 531 toward the rotor 300. Multiple inner cores 535 are arranged in the circumferential direction CD. A coil portion 211 is attached to the inner core 535. The coil portion 211 is wound around the inner core 535.

[0116] In the core 530, the back core 531 has a laminated structure, and the inner core 535 has an aggregated structure. As shown in Figure 27, the back core 531 has a plurality of magnetic plate materials 232, similar to the teeth 231 of the first embodiment. In the back core 531, the plurality of magnetic plate materials 232 are laminated in the axial direction AD. The magnetic plate materials 232 extend in a direction perpendicular to the axial direction AD. The back core 531 corresponds to the first core member. The inner core 535 has magnetic powder 236, similar to the flange 235 of the first embodiment. In the inner core 535, the aggregated plurality of magnetic powders 236 are joined to each other. The inner core 535 corresponds to the second core member.

[0117] In core 530, the inner core 535 is housed inside the coil portion 211, while the back core 531 is not housed inside the coil portion 211. The inner core 535 does not protrude axially AD from the coil portion 211 on either the rotor 300 side or the back core 531 side. The back core 531 does not extend inside the coil portion 211. The boundary between the back core 531 and the inner core 535 is located at the end of the coil portion 211, aligned circumferentially CD and radially RD.

[0118] In this embodiment, as a modification 3-1, as shown in Figure 28, at least a portion of the back core 531 may extend inside the coil portion 211. In this configuration, the protruding portion of the back core 531 extends inside the coil portion 211. The protruding portion extends radially RD from the back core 531 toward the rotor 300.

[0119] Furthermore, in this embodiment, the inner core 535 may protrude radially RD from the coil portion 211. For example, the inner core 535 may protrude toward the rotor 300 side from the coil portion 211, or it may protrude toward the back core 531 side from the coil portion 211.

[0120] <Other Embodiments> The disclosures in this specification are not limited to the exemplary embodiments. The disclosures encompass the exemplary embodiments and variations thereof by those skilled in the art. For example, the disclosures are not limited to the combinations of parts and elements shown in the embodiments, but can be implemented in various variations. The disclosures can be implemented in a variety of combinations. The disclosures may have additional parts that can be added to the embodiments. The disclosures encompass embodiments in which parts and elements have been omitted. The disclosures encompass substitutions or combinations of parts and elements between one embodiment and another. The scope of the disclosed technical field is not limited to the descriptions of the embodiments. The scope of the disclosed technical field is indicated by the claims and should be understood to include all modifications within the meaning and scope equivalent to the claims.

[0121] In each of the above embodiments, the second member, such as the magnetic powder 236, may be smaller than the first member, such as the magnetic plate material 232. The second member may be smaller than the first member in terms of length, thickness, volume, etc. For example, the second member may be formed in a plate shape so as to be smaller than the first member. Multiple second members may be stacked in a direction different from the direction in which the multiple first members are stacked. For example, in the first embodiment above, while multiple first members are stacked in the radial direction RD, multiple second members may be stacked in the circumferential direction CD or the axial direction AD.

[0122] In each of the above embodiments, in the stator core such as the core 230, a third member different from the core bonding portion 250 may be provided between the first core member such as the teeth 231 and the second core member such as the flange 235. For example, the third member may be a plate-shaped member extending in a different direction from the first member.

[0123] In each of the above embodiments, the aircraft on which the motor device 60 is mounted does not have to be a vertical take-off and landing aircraft, as long as it is electrically powered. For example, the aircraft may be an electric aircraft capable of taking off and landing with a runway. Furthermore, the aircraft may be a rotary-wing aircraft or a fixed-wing aircraft. The aircraft may be an unmanned aircraft that does not carry a person. The unmanned aircraft may have a crew compartment 14 or it may not have a crew compartment 14. Also, the pilot may remotely control the aircraft. The eVTOL 10 may be referred to as a manned aircraft even if it does not carry a person, as long as it is capable of carrying a person.

[0124] In each of the above embodiments, the mobile body on which the motor device 60 is mounted does not have to be an aircraft, as long as it can be moved by the rotation of a rotating body. For example, the mobile body may be a vehicle, a ship, construction machinery, or agricultural machinery. For example, if the mobile body is a vehicle or construction machinery, the rotating body may be a wheel for movement, and the output shaft may be an axle. If the mobile body is a ship, the rotating body may be a screw propeller for propulsion, and the output shaft may be a propeller shaft. The mobile body may also be an automated guided vehicle (AGV) or an electric wheelchair. For example, an AGV or an electric wheelchair may be equipped with a relatively small motor device 60.

[0125] In each of the above embodiments, the motor device 60 is not necessarily mounted on a moving object. For example, the motor device 60 may be installed on stationary equipment, machinery, or devices. Thus, the motor device 60 is not limited to moving objects and can be used as a drive device for various applications.

[0126] (Disclosure of Technical Ideas) This specification discloses several technical ideas as described in the following paragraphs. Some paragraphs may be written in a multiple dependent form, where subsequent paragraphs optionally refer to preceding paragraphs. Furthermore, some paragraphs may be written in a multiple dependent form, where they refer to other multiple dependent forms. These paragraphs written in multiple dependent forms define several technical ideas.

[0127] (Technical Concept 1) A stator core (230) provided on the stator (200) of a rotating electric machine (60), to which an energizable coil section (211) is attached, comprising: a first core member (231, 431, 531) having a plate-shaped first member (232) and a plurality of stacked first members joined together; and a second core member (235, 435, 535) having a second member (236) smaller than the first member and a plurality of assembled second members joined together.

[0128] (Technical Concept 2) The stator core according to Technical Concept 1, wherein the second core member has magnetic powder as the second member, and is formed by joining a plurality of the magnetic powders together.

[0129] (Technical Concept 3) The stator core according to technical concept 1 or 2, wherein the first core member and the second core member are arranged in one direction (AD, RD).

[0130] (Technical Idea 4) A stator core according to any one of technical ideas 1 to 3, comprising an adhesive portion (250) provided between the first core member and the second core member, which bonds the first core member and the second core member together.

[0131] (Technical Idea 5) The stator core according to Technical Idea 4, wherein the adhesive portion adheres the end face (231a) of the first core member and the end face (240a) of the covering portion (240) that is provided to cover the outer peripheral surface (231b) of the first core member and the adhesive surface (235a) of the second core member.

[0132] (Technical Concept 6) A rotating electric machine (60) driven by the supply of electricity, comprising: a stator (200) having an energizable coil section (211) and a stator core (230) to which the coil section is attached; and a rotor (300) that rotates around a rotation axis (Cm) relative to the stator, wherein the stator core comprises: a first core member (231) having a plate-shaped first member (232) and a plurality of stacked first members joined together; and a second core member (235) having a second member (236) smaller than the first member and a plurality of assembled second members joined together.

[0133] (Technical Concept 7) The rotating electric machine according to Technical Concept 6, wherein the stator and the rotor are arranged in a first direction (AD), the first core member is provided on the rotor in a position aligned in the first direction to restrict the generation of a first eddy current (Im1) in the stator core by a first magnetic flux (M1) passing through the stator core in the first direction, and the second core member is provided between the first core member and the rotor in the first direction to restrict the generation of a second eddy current (Im2) in the stator core by a second magnetic flux (M2) passing through the stator core in a second direction (RD) perpendicular to the first direction.

[0134] (Technical idea 8) The stator core has a core-facing surface (230a) facing the stator, and the second core member is provided on the rotor side of the first core member and forms the core-facing surface, as described in technical idea 6 or 7.

[0135] (Technical Idea 9) The stator and the rotor are arranged in the axial direction (AD) of the rotation axis, and the second core member extends toward the rotor in the axial direction, as described in any one of Technical Ideas 6 to 8.

[0136] (Technical Concept 10) A method for manufacturing a stator core (230) provided on the stator (200) of a rotating electric machine (60) and to which an energizable coil section (211) is attached, comprising: a first preparation step (P101, P103) for preparing a first core member (231) having a plate-shaped first member (232) and formed by joining a plurality of stacked first members; a second preparation step (P101, P102) for preparing a second core member (235) having a second member (236) smaller than the first member and formed by joining a plurality of assembled second members; and a fixing step (P105 to P107) for fixing the first core member and the second core member.

[0137] (Technical Idea 11) The method for manufacturing a stator core according to technical idea 10, wherein the fixing step comprises: a polishing step (P105) of polishing at least one of the first fixing surface (231a) of the first core member and the second fixing surface (235a) of the second core member; a coating step (P106) of applying an adhesive (251) to at least one of the first fixing surface and the second fixing surface; and a bonding step (P107) of bonding the first fixing surface and the second fixing surface with the adhesive.

[0138] (Technical idea 12) A method for manufacturing a stator core according to technical idea 11, comprising: a coating step (P104) of providing a covering portion (240) so as to cover the outer peripheral surface (231b) of the first core member, wherein the coating step involves applying the adhesive to the covering fixing surface (240a) of the covering portion, and the bonding step involves bonding both the first fixing surface and the covering fixing surface to the second fixing surface with the adhesive.

Claims

1. A stator core (230) provided on the stator (200) of a rotating electric machine (60), to which an energizable coil section (211) is attached, comprising: a first core member (231, 431, 531) having a plate-shaped first member (232) and a plurality of stacked first members joined together; and a second core member (235, 435, 535) having a second member (236) smaller than the first member and a plurality of assembled second members joined together.

2. The stator core according to claim 1, wherein the second core member has magnetic powder as the second member, and is formed by joining a plurality of the magnetic powders together.

3. The stator core according to claim 1 or 2, wherein the first core member and the second core member are arranged in one direction (AD, RD).

4. The stator core according to claim 1 or 2, further comprising: an adhesive portion (250) provided between the first core member and the second core member, which bonds the first core member and the second core member together.

5. The stator core according to claim 4, wherein the adhesive portion adheres the end face (231a) of the first core member and the end face (240a) of the covering portion (240) that is provided to cover the outer peripheral surface (231b) of the first core member and the adhesive surface (235a) of the second core member.

6. A rotating electric machine (60) driven by the supply of power, comprising: a stator (200) having an energizable coil section (211) and a stator core (230) to which the coil section is attached; and a rotor (300) that rotates around a rotation axis (Cm) relative to the stator, wherein the stator core comprises: a first core member (231) having a plate-shaped first member (232) and a plurality of stacked first members joined together; and a second core member (235) having a second member (236) smaller than the first member and a plurality of assembled second members joined together.

7. The rotating electric machine according to claim 6, wherein the stator and the rotor are arranged in a first direction (AD), the first core member is provided on the rotor in a position aligned in the first direction to restrict the generation of a first eddy current (Im1) in the stator core by a first magnetic flux (M1) passing through the stator core in the first direction, and the second core member is provided between the first core member and the rotor in the first direction to restrict the generation of a second eddy current (Im2) in the stator core by a second magnetic flux (M2) passing through the stator core in a second direction (RD) perpendicular to the first direction.

8. The rotating electric machine according to claim 6 or 7, wherein the stator core has a core-facing surface (230a) facing the stator, and the second core member is provided on the rotor side of the first core member and forms the core-facing surface.

9. The rotating electric machine according to claim 6 or 7, wherein the stator and the rotor are arranged in the axial direction (AD) of the rotation axis, and the second core member extends in the axial direction toward the rotor.

10. A manufacturing method for a stator core (230) provided on the stator (200) of a rotating electric machine (60) and to which an energizable coil section (211) is attached, comprising: a first preparation step (P101, P103) of preparing a first core member (231) having a first member (232) formed in the shape of a plate, and a plurality of stacked first members being joined together; a second preparation step (P101, P102) of preparing a second core member (235) having a second member (236) smaller than the first member, and a plurality of assembled second members being joined together; and a fixing step (P105 to P107) of fixing the first core member and the second core member.

11. The method for manufacturing a stator core according to claim 10, wherein the fixing step comprises: a polishing step (P105) of polishing at least one of the first fixing surface (231a) of the first core member and the second fixing surface (235a) of the second core member; a coating step (P106) of applying an adhesive (251) to at least one of the first fixing surface and the second fixing surface; and a bonding step (P107) of bonding the first fixing surface and the second fixing surface with the adhesive.

12. A method for manufacturing a stator core according to claim 11, comprising: a coating step (P104) of providing a covering portion (240) so as to cover the outer peripheral surface (231b) of the first core member, wherein the coating step involves applying the adhesive to the covering fixing surface (240a) of the covering portion, and the bonding step involves bonding both the first fixing surface and the covering fixing surface to the second fixing surface with the adhesive.

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