WO2018225656A1

WO2018225656A1 - Rotating electric machine

Info

Publication number: WO2018225656A1
Application number: PCT/JP2018/021239
Authority: WO
Inventors: 佳純北原; 高橋　裕樹
Original assignee: 株式会社デンソー
Priority date: 2017-06-05
Filing date: 2018-06-01
Publication date: 2018-12-13
Also published as: JP6737238B2; JP2018207667A

Abstract

A rotating electric machine provided with a stator and a rotor which is disposed on the inside in the radial direction of the stator and opposed to the stator in the radial direction. The rotor includes: a field magnet core which includes a tubular boss portion and a plurality of nail-shaped magnetic pole portions which are disposed on the outside in the radial direction of the boss portion and formed with magnetic poles with polarities alternately varying in the circumferential direction; a field magnet winding which is wound around the outer periphery of the boss portion and generates magnetomotive force upon being energized; and a plurality of permanent magnets which are respectively disposed between two nail-shaped magnetic pole portions adjacent to each other in the circumferential direction with the magnetization easy axis of the permanent magnets oriented in the circumferential direction, and which are formed with magnetic poles so as to match the polarities appearing in the two nail-shaped magnetic pole portions due to the magnetomotive force of the field magnet winding. Magnetic resistance between the nail-shaped magnetic pole portions of each pair and the permanent magnets opposing each other in the circumferential direction is greater in a radially outside position far from the stator than in a radially inside position close to the stator.

Description

Rotating electric machine

The present disclosure relates to a rotating electrical machine including a stator and a rotor.

Conventionally, a rotating electrical machine including a stator and a rotor is known. For example, Patent Literature 1 includes a field winding and a plurality of claw-shaped magnetic pole portions in which magnetic poles having different polarities are alternately formed in the circumferential direction (rotation direction) by the magnetomotive force of the field winding. An automotive alternator having a Landel rotor is disclosed. Each of the Landel rotors is disposed between two claw-shaped magnetic pole portions adjacent to each other in the circumferential direction, and the magnetic poles are matched with the polarities appearing in the two claw-shaped magnetic pole portions by the magnetomotive force of the field winding. A plurality of permanent magnets are formed. With these permanent magnets, a higher power density can be obtained. In such an AC generator for vehicles, the optimum design is made for the size of the permanent magnet and the shape of the boss, disk, and claw-shaped magnetic poles of the rotor core of the Landel rotor. The coexistence with the reduction of electromotive force is achieved.

JP-A-4-255451

In recent years, the space for mounting vehicle alternators and starters on vehicles has been minimised with the slant nose of vehicles to reduce running resistance and the miniaturization of engine rooms. In such a situation, functions that are regarded as important for the vehicle alternator include a starter function and a power running and regenerative braking function for assisting the vehicle with high-efficiency operation. Therefore, attention is paid to the power generation, torque generation, and regenerative braking capability of the vehicle AC generator when the field current becomes a large current in a short period of time. When this field current becomes a large current in a short period of time, both the field magnetic field generated by the rotor itself and the excitation magnetic field generated from the stator around which the armature winding is wound are strong demagnetizing fields (demagnetizing fields). )

Generally, as in the Landel rotor disclosed in Patent Document 1, an electromagnet / permanent magnet combined type in which a parallel magnetic circuit having at least two of a magnetic circuit using a permanent magnet and a magnetic circuit using a field core is formed. In the rotor, when the field current becomes a large current in a short period, the permanent magnet simultaneously receives a strong demagnetizing field from the field winding and a strong demagnetizing field from the stator armature winding. When a strong demagnetizing field is applied to the permanent magnet, the permanent magnet may be greatly demagnetized.

The present disclosure has been made in view of the above circumstances, and an object thereof is to provide a rotating electrical machine capable of improving the demagnetization resistance performance of a permanent magnet.

A rotating electrical machine according to the present disclosure includes an annular stator core, a stator having an armature winding wound around the stator core, and a rotor disposed radially opposite to the stator on the radially inner side of the stator. Prepare. The rotor has a cylindrical boss portion, and a field core having a plurality of claw-shaped magnetic pole portions that are arranged on the radially outer side of the boss portion and in which magnetic poles having different polarities are alternately formed in the circumferential direction (rotating direction). The field winding wound around the outer periphery of the boss part and generating a magnetomotive force when energized, and the easy axis of magnetization between the two claw-shaped magnetic pole parts adjacent to each other in the circumferential direction are oriented in the circumferential direction. And a plurality of permanent magnets having magnetic poles formed so as to coincide with the polarities appearing in the two claw-shaped magnetic pole portions by the magnetomotive force of the field winding. And the magnetic resistance between each pair of claw-shaped magnetic pole portions facing each other in the circumferential direction and the permanent magnet is larger at a radially outer position closer to the stator than a radially inner position far from the stator.

According to the above configuration, the magnetic flux flowing in the circumferential direction between the claw-shaped magnetic pole portion and the permanent magnet is difficult to flow on the radially outer side and easily flows on the radially inner side. Therefore, the magnetic flux generated by the excitation magnetic field generated in the armature winding of the stator that flows from the stator to the claw-shaped magnetic pole portion is guided to the radially inner portion of the claw-shaped magnetic pole portion, and the permanent magnet The magnetic flux flowing out is dispersed over the entire length in the radial direction of the opposite part. Thereby, the influence of the demagnetizing field (the excitation magnetic field) received by the permanent magnet can be made uniform over the entire radial length of the permanent magnet. Therefore, local demagnetization of the permanent magnet can be prevented, and its demagnetization resistance can be improved.

In the above rotating electric machine, the distance between the opposed surfaces of each pair of claw-shaped magnetic pole portions facing each other in the circumferential direction and the permanent magnet may be longer at the radially outer position than at the radially inner position.

According to the above configuration, the magnetic resistance between each pair of claw-shaped magnetic pole portions facing each other in the circumferential direction and the permanent magnet can be increased at a radially outer position closer to the stator than a radially inner position far from the stator. it can. Therefore, since the influence of the demagnetizing field applied to the permanent magnet can be made uniform over the entire radial length of the permanent magnet, local demagnetization of the permanent magnet can be prevented and its anti-demagnetization performance can be improved. Can do.

Further, in each pair of claw-shaped magnetic pole portions and permanent magnets facing each other in the circumferential direction, at least one of the claw-shaped magnetic pole portions and the permanent magnet has a hollow portion recessed in the circumferential direction at a radially outer position of the facing surface. May be.

According to the above configuration, the distance between the opposing surfaces at the radially outer position where the recess is present can be made longer than the distance between the opposing surfaces at the radially inner position where the recess is not present. For this reason, the magnetic resistance between each pair of claw-shaped magnetic pole portions facing each other in the circumferential direction and the permanent magnet can be increased at a radially outer position closer to the stator than a radially inner position far from the stator. Therefore, since the influence of the demagnetizing field applied to the permanent magnet can be made uniform over the entire radial length of the permanent magnet, local demagnetization of the permanent magnet can be prevented and its anti-demagnetization performance can be improved. Can do.

Furthermore, the hollow part may be provided in the claw-shaped magnetic pole part, and the rotor may have a magnet holder that holds a permanent magnet partially accommodated in the hollow part. According to this configuration, a part of the magnet holder that holds the permanent magnet can be accommodated in the recess of the claw-shaped magnetic pole part, and the permanent magnet can be positioned (fixed) with respect to the claw-shaped magnetic pole part. .

Further, the claw-shaped magnetic pole part has a hollow part and a protruding part protruding in the circumferential direction on the radially outer side of the hollow part, and the magnet holder has a wall surface and a protruding part of the claw-shaped magnetic pole part forming the hollow part. It may be locked to.

According to the above configuration, the movement of the magnet holder, and thus the permanent magnet held by the magnet holder, can be restricted with respect to the claw-shaped magnetic pole portion. For this reason, it is possible to reduce the occurrence of vibration or peeling of the permanent magnet due to the demagnetizing field, and the occurrence of cracking or chipping due to the shock magnetic field when the permanent magnet is magnetized.

Alternatively, the rotor has a cylindrical iron core member disposed on the radially outer side of the claw-shaped magnetic pole portion so as to cover the outer peripheral surface of the claw-shaped magnetic pole portion, and the magnet holder is recessed with the inner peripheral surface of the iron core member. It may be fitted and fixed in a space formed between the wall surfaces of the claw-shaped magnetic pole part forming the part.

According to the above configuration, the movement of the magnet holder, and thus the permanent magnet held by the magnet holder, can be restricted with respect to the claw-shaped magnetic pole portion and the iron core member. For this reason, it is possible to reduce the occurrence of vibration or peeling of the permanent magnet due to the demagnetizing field, and the occurrence of cracking or chipping due to the shock magnetic field when the permanent magnet is magnetized. Also, the claw-shaped magnetic pole dent necessary to accommodate a part of the magnet holder and the claw-shaped magnetic pole dent necessary to prevent local demagnetization of the permanent magnet are used together. can do. For this reason, simplification of the shape of the claw-shaped magnetic pole part and facilitation of molding can be achieved. Furthermore, since the iron core member is disposed so as to cover the outer peripheral surface of the claw-shaped magnetic pole portion, all the claw-shaped magnetic pole portions arranged in the circumferential direction can be connected to each other via the iron core member. For this reason, even if the centrifugal force acting on the rotor increases as the weight of the permanent magnet increases, the deformation of the claw-shaped magnetic pole portion can be reliably suppressed, and the strength reduction can be suppressed.

Further, the magnet holder may be formed of a magnetic material. According to this configuration, since the magnet holder, which is a magnetic body, is disposed between the permanent magnet held by the magnet holder and the claw-shaped magnetic pole portion over substantially the entire radial direction, the magnetic resistance of the entire permanent magnet is lowered. And its permeance can be increased. As a result, the demagnetizing field of the permanent magnet can be further reduced.

In the above rotating electric machine, the magnetic permeability of at least one of the opposed portions of the pair of claw-shaped magnetic pole portions facing each other in the circumferential direction and the permanent magnet may be smaller at the radially outer position than at the radially inner position.

In the above rotating electric machine, the permanent magnet may be magnetized while being assembled between the claw-shaped magnetic pole portions adjacent in the circumferential direction.

According to the above configuration, the magnetic flux generated by the magnetizing magnetic field flowing in the circumferential direction between the claw-shaped magnetic pole portion and the permanent magnet is less likely to flow radially outside and easily flows radially inside. Therefore, the magnetic flux due to the magnetized magnetic field that has flowed to the claw-shaped magnetic pole part is guided to the radially inner portion of the claw-shaped magnetic pole part, and the magnetic flux by the magnetized magnetic field that flows from the claw-shaped magnetic pole part to the permanent magnet is the opposite part. Are distributed over the entire length in the radial direction. Thereby, the magnetization magnetic field which acts on a permanent magnet can be made uniform over the radial direction full length of the permanent magnet. As a result, it is possible to prevent the permanent magnets from being unevenly magnetized in the radial direction.

It is sectional drawing which shows the whole structure of the rotary electric machine which concerns on one Embodiment. It is the top view which looked at the rotor of the rotary electric machine which concerns on this embodiment from the radial direction outer side. It is a perspective view of the rotor of the rotary electric machine which concerns on this embodiment. It is a perspective view of the rotor of the rotary electric machine which concerns on this embodiment in the state which removed the cylindrical iron core member which covers the outer periphery of a claw-shaped magnetic pole part. It is the top view which looked at a part of rotor of the rotary electric machine which concerns on this embodiment from the axial direction. It is a graph which shows the demagnetization curve in case the irreversible demagnetization arises in a permanent magnet in the rotor which concerns on a comparative example. It is a graph which shows the demagnetization curve when an irreversible demagnetization does not arise in a permanent magnet by the method of setting the magnetic resistance of the rotor which concerns on this embodiment. It is a flowchart which shows the assembly procedure of the rotor which concerns on this embodiment. It is the top view which looked at the magnet holder of the rotor which concerns on this embodiment, and its periphery from the axial direction. It is a perspective view of the magnet holder of the rotor which concerns on this embodiment. It is the top view which looked at the magnet holder of the rotor which concerns on one modification, and its periphery from the axial direction. It is the top view which looked at some rotors concerning other modifications from an axial direction. It is the top view which looked at some rotors concerning other modifications from an axial direction.

Hereinafter, an embodiment and its modifications will be described with reference to FIGS.

First, the overall configuration of a rotating electrical machine 1 according to an embodiment will be described with reference to FIG. The rotating electrical machine 1 is mounted on a vehicle, for example, and generates a driving force for driving the vehicle when power is supplied from a power source such as a battery. Moreover, the driving force is supplied from the engine of the vehicle to generate electric power for charging the battery. That is, the rotating electrical machine 1 is configured as a three-phase AC motor generator. As shown in FIG. 1, the rotating electrical machine 1 includes a housing 10, a stator 20, a rotor 30, a brush device 40, a rectifier 50, a voltage regulator 60, and a pulley 70.

The housing 10 accommodates the stator 20 and the rotor 30. In addition, the housing 10 supports a rotating shaft 80 fitted to the rotor 30 so as to be rotatable via a bearing, and fixes the stator 20.

The stator 20 generates a magnetic field that rotates the rotor 30 when a three-phase alternating current flows. The stator 20 generates an electromotive force when a rotating magnetic field generated by the rotation of the rotor 30 is applied. Specifically, the stator 20 includes a stator core 21 and an armature winding (stator winding) 22. The stator core 21 is formed in an annular shape (hollow cylindrical shape). The stator core 21 is made of a soft magnetic material and constitutes a part of the magnetic path. For example, in the present embodiment, the stator core 21 is formed by laminating electromagnetic steel plates made of iron or silicon steel in the axial direction. The stator core 21 has an annular back core portion, a plurality of teeth extending radially inward from the back core portion and arranged at predetermined intervals in the circumferential direction (rotating direction), each of which is in the circumferential direction. A plurality of slots formed between two teeth adjacent to each other.

The armature winding 22 is wound around the stator core 21. The armature winding 22 has a slot accommodating portion that is accommodated in a slot of the stator core 21 and a pair of coil end portions that protrude outward in the axial direction from both axial ends of the stator core 21. The armature winding 22 is a multiphase winding (specifically, a three-phase winding in the present embodiment). Each phase winding of the armature winding 22 is connected to an inverter device (not shown). The voltage applied to each phase winding is controlled by opening / closing a switching element in the inverter device.

The rotor 30 is disposed radially opposite to the stator 20 with a predetermined air gap inside the stator 20 (specifically, the tip of the teeth) in the radial direction. The rotor 30 can apply a rotating magnetic field to the armature winding 22 by rotating. In the present embodiment, the rotor 30 is configured as a Landel rotor. The rotor 30 includes a field core 31, a field winding 32, an iron core member 33, and a permanent magnet 34.

The field core 31 is made of a soft magnetic material and constitutes a part of the magnetic path. The field core 31 has one boss portion 35, a pair of disk portions 36, and a plurality of (for example, 16) claw-shaped magnetic pole portions 37. Specifically, in the present embodiment, the field core 31 is configured by a pair of pole cores that are divided into two in the axial direction. Each pole core includes a half of the boss portion 35, one disk portion 36 of the pair of disk portions 36, and a half claw-shaped magnetic pole portion 37 of the plurality of claw-shaped magnetic pole portions 37. The field core 31 is forged, for example.

The boss portion 35 has a hollow cylindrical shape and is fitted and fixed to the outer periphery of the rotating shaft 80. The pair of disk portions 36 respectively extend radially outward from both axial end portions of the boss portion 35 and have a disk shape as a whole. Specifically, each disk portion 36 has one annular base portion connected to the boss portion 35, extends radially outward from the base portion, and is spaced at a predetermined interval in the circumferential direction (rotation direction) of the rotation shaft 80. A plurality of protrusions. Each claw-shaped magnetic pole part 37 is connected to one projecting part of the corresponding disk part 36 and extends in the axial direction of the rotary shaft 80 from the projecting part. Each claw-shaped magnetic pole part 37 is arranged with a gap on the radially outer side with respect to the boss part 35. Each claw-shaped magnetic pole portion 37 is formed in a claw shape as a whole, and its outer peripheral surface is substantially arc-shaped.

The claw-shaped magnetic pole part 37 includes a plurality of first claw-shaped magnetic pole parts 37-1 and a plurality of second claw-shaped magnetic pole parts 37- in which magnetic poles having different polarities (specifically, N and S poles) are formed. 2 is included. That is, one pole core of the pair of pole cores has the first claw-shaped magnetic pole part 37-1, and the other pole core has the second claw-shaped magnetic pole part 37-2. The number of first claw-shaped magnetic pole portions 37-1 and the number of second claw-shaped magnetic pole portions 37-2 are set to the same number (for example, eight). Further, as shown in FIG. 4, the first claw-shaped magnetic pole portions 37-1 and the second claw-shaped magnetic pole portions 37-2 are alternately arranged in the circumferential direction. A gap 38 is formed between each pair of first claw-shaped magnetic pole portions 37-1 and second claw-shaped magnetic pole portions 37-2 adjacent in the circumferential direction.

The first claw-shaped magnetic pole portion 37-1 and the second claw-shaped magnetic pole portion 37-2 are arranged such that the axial bases (or the axial front end sides) connected to the corresponding disk portions 36 are opposite to each other in the axial direction. ing. The first claw-shaped magnetic pole part 37-1 and the second claw-shaped magnetic pole part 37-2 are magnetized with different polarities. The first claw-shaped magnetic pole part 37-1 is connected to the disk part 36 that extends radially outward from one axial end of the boss part 35, and the disk that extends radially outward from the other axial end of the boss part 35. It extends in the axial direction toward the portion 36. On the other hand, the second claw-shaped magnetic pole part 37-2 is connected to the disk part 36 that spreads radially outward from the other axial end of the boss part 35, and radially extends from one axial end of the boss part 35. It extends in the axial direction toward the disk portion 36 spreading outward. The first claw-shaped magnetic pole part 37-1 and the second claw-shaped magnetic pole part 37-2 are formed in a shape common to each other except for the arrangement position and the axially extending direction.

Each claw-shaped magnetic pole part 37 has a predetermined width (that is, a circumferential width) in the circumferential direction and a predetermined thickness (that is, a radial thickness) in the radial direction. Each claw-shaped magnetic pole portion 37 is formed so that the circumferential width gradually decreases and the radial thickness gradually decreases from the proximal end portion (root portion) connected to the corresponding disk portion 36 to the distal end portion. ing. That is, each claw-shaped magnetic pole portion 37 is formed so as to become thinner in both the circumferential direction and the radial direction from the base end portion to the tip end portion. Each claw-shaped magnetic pole part 37 is preferably formed symmetrically with respect to the center in the circumferential direction.

The gap 38 is provided between the first claw-shaped magnetic pole part 37-1 and the second claw-shaped magnetic pole part 37-2 adjacent in the circumferential direction. The gap 38 extends obliquely with respect to the axial direction (that is, is inclined at a predetermined angle with respect to the rotating shaft 80 of the rotor 30). Each gap 38 has a circumferential dimension (that is, a circumferential dimension) that hardly changes depending on the axial position, that is, a pole whose circumferential dimension is constant or includes the constant value. It is set to be maintained within a slight range. One permanent magnet 34 is disposed in each gap 38.

The field winding 32 is disposed in the radial gap between the boss portion 35 and the claw-shaped magnetic pole portion 37. The field winding 32 is wound around the outer periphery of the boss portion 35. The field winding 32 generates a magnetic flux when energized with a DC field current. The magnetic flux generated by the field winding 32 is guided to the claw-shaped magnetic pole part 37 through the boss part 35 and the disk part 36 of the field core 31. That is, the boss portion 35 and the disk portion 36 form a magnetic path that guides the magnetic flux generated in the field winding 32 to the claw-shaped magnetic pole portion 37. The field winding 32 magnetizes the first claw-shaped magnetic pole part 37-1 to the N pole and the second claw-shaped magnetic pole part 37-2 to the S pole by the generated magnetic flux.

As shown in FIGS. 2 and 3, the iron core member 33 is substantially cylindrical and has claw-shaped magnetic pole portions 37 (that is, the first claw-shaped magnetic pole portion 37-1 and the second claw-shaped magnetic pole portion 37-2). It arrange | positions so that the outer peripheral surface of the nail | claw-shaped magnetic pole part 37 may be covered to radial direction outer side. The iron core member 33 has an axial length that is about the distance from the connecting portion of each claw-shaped magnetic pole portion 37 to the corresponding disk portion 36 to the tip of the claw-shaped magnetic pole portion 37 in the axial direction. The iron core member 33 is a thin skin member having a predetermined thickness in the radial direction. The radial thickness is set, for example, in the range of 0.6 mm to 1.0 mm, which can achieve both the mechanical strength and the magnetic performance of the rotor 30. The iron core member 33 is disposed so as to face the arcuate outer peripheral surface of the claw-shaped magnetic pole portion 37 and is in contact with the claw-shaped magnetic pole portion 37. The iron core member 33 is disposed so as to close the gap 38 between the first claw-shaped magnetic pole portion 37-1 and the second claw-shaped magnetic pole portion 37-2 adjacent in the circumferential direction on the outer side in the radial direction. The claw-shaped magnetic pole portions 37-1 and 37-2 are magnetically connected to each other.

The iron core member 33 is made of a metal material having soft magnetic properties. The iron core member 33 may be constituted by a cylindrical pipe or a laminated body in which a plurality of punched thin plates are laminated in the axial direction. Alternatively, the iron core member 33 may be formed by winding or rolling a wire rod and fitting. The iron core member 33 is fixed to the claw-shaped magnetic pole portion 37 by shrink fitting, press fitting, welding, or a combination thereof. The thin plate-like, wire-like, and belt-like members constituting the iron core member 33 preferably have a rectangular cross section from the viewpoint of strength and magnetic performance, but may have a circular shape or a cross section with a curved corner. Good.

The iron core member 33 has a function of smoothing the outer periphery of the rotor 30 and reducing wind noise caused by unevenness formed on the outer periphery of the rotor 30. In addition, the iron core member 33 mechanically connects a plurality of claw-shaped magnetic pole portions 37 arranged in the circumferential direction to each other, so that when the centrifugal force is applied, deformation of each claw-shaped magnetic pole portion 37 (particularly radially outward). It has a function of suppressing deformation.

The permanent magnet 34 is accommodated inside the core member 33 in the radial direction. Each permanent magnet 34 is formed between two claw-shaped magnetic pole portions 37 adjacent in the circumferential direction, that is, between a pair of first claw-shaped magnetic pole portions 37-1 and a second claw-shaped magnetic pole portion 37-2. It arrange | positions so that the clearance gap 38 may be filled up. That is, the permanent magnet 34 is a magnet between magnetic poles. The permanent magnets 34 are arranged for each gap 38, and the same number as the number of the gaps 38 is provided.

Each permanent magnet 34 is generally formed in a rectangular parallelepiped shape. Each permanent magnet 34 extends obliquely with respect to the axial direction so as to incline in the circumferential direction (that is, inclines at a predetermined angle with respect to the rotating shaft 80 of the rotor 30). Each permanent magnet 34 reduces leakage of magnetic flux between two claw-shaped magnetic pole portions 37 adjacent in the circumferential direction, and reinforces the magnetic flux flowing between the two claw-shaped magnetic pole portions 37 and the stator core 21 of the stator 20. It has a function.

Each permanent magnet 34 is arranged such that a magnetic pole is formed in such a direction as to reduce the leakage flux between two claw-shaped magnetic pole portions 37 adjacent in the circumferential direction, that is, the easy magnetization axis is directed in the circumferential direction. ing. Specifically, each permanent magnet 34 has a magnetic pole on the side surface in the circumferential direction facing the corresponding first claw-shaped magnetic pole portion 37-1 that is magnetized to the N pole, and is magnetized to the S pole. The circumferential claw poles facing the second claw-shaped magnetic pole portion 37-2 are provided so as to be S poles. In the present embodiment, each permanent magnet 34 is incorporated in the rotor 30 and magnetized in a state of being assembled between two claw-shaped magnetic pole portions 37-1 and 37-2 that are adjacent in the circumferential direction.

Each permanent magnet 34 is held by one magnet holder 39 and integrated with the magnet holder 39. Each permanent magnet 34 is held and fixed to the rotor 30 using a magnet holder 39. Each permanent magnet 34 is held and fixed to the rotor 30 in a state where the permanent magnet 34 is completely or partially covered by the magnet holder 39. The magnet holder 39 is formed of a so-called soft magnetic material attracted by a magnet such as iron. For this reason, since the magnetic holder 39 can short-circuit the magnetic flux generated by the permanent magnet 34 when the rotating electrical machine 1 is not loaded, generation of a counter electromotive voltage can be suppressed and damage to the equipment of the load circuit can be suppressed. Can do.

The brush device 40 has a pair of slip rings 41 and a pair of brushes 42. The slip ring 41 is fixed to one end of the rotating shaft 80 in the axial direction (the right end in FIG. 1). The slip ring 41 has a function of supplying a DC field current to the field winding 32 of the rotor 30. The brush 42 is held by a brush holder attached and fixed to the housing 10. Each brush 42 is arranged in a state of being pressed against the rotating shaft 80 side by a spring so that its radially inner end slides on the surface of the corresponding slip ring 41. The brush 42 causes a field current to flow through the field winding 32 via the slip ring 41.

The rectifier 50 is electrically connected to the armature winding 22 of the stator 20. The rectifier 50 is a device that rectifies and outputs the alternating current generated in the armature winding 22 to direct current. The voltage regulator 60 adjusts the output voltage of the rotating electrical machine 1 by controlling the field current flowing through the field winding 32. The voltage regulator 60 has a function of maintaining the output voltage that changes according to the electric load and the amount of power generation substantially constant. The pulley 70 is fastened and fixed to the other axial end portion (the left end portion in FIG. 1) of the rotary shaft 80 so as to transmit the rotational force (torque) generated by the vehicle engine to the rotor 30 of the rotating electrical machine 1.

In the rotating electrical machine 1 having the above configuration, when a field current is supplied from the power source to the field winding 32 of the rotor 30 via the brush device 40, the boss portion 35, the disk portion 36, and the claw-shaped magnetic pole portion. The magnetic flux which flows through 37 is generated. Specifically, this magnetic flux is generated, for example, by the boss portion 35 → the disk portion 36 of one pole core → the first claw-shaped magnetic pole portion 37-1 → the stator core 21 → the second claw-shaped magnetic pole portion 37-2 → the disk of the other pole core. A magnetic circuit that flows in the order of the portion 36 → the boss portion 35 is formed.

When the magnetic flux is guided to the first claw-shaped magnetic pole part 37-1 and the second claw-shaped magnetic pole part 37-2, the first claw-shaped magnetic pole part 37-1 is magnetized to the N pole and the second claw-shaped magnetic pole part 37-1 is magnetized. The magnetic pole part 37-2 is magnetized to the south pole. When the direct current supplied from the power source is converted into, for example, a three-phase alternating current and supplied to the armature winding 22 in a state where the claw-shaped magnetic pole portion 37 is magnetized, the rotor 30 rotates with respect to the stator 20. To do. As a result, the rotating electrical machine 1 functions as an electric motor.

On the other hand, the rotor 30 of the rotating electrical machine 1 rotates when the rotational torque generated by the vehicle engine is transmitted to the rotating shaft 80 via the pulley 70. The rotation of the rotor 30 applies a rotating magnetic field to the armature winding 22 of the stator 20, thereby generating an AC electromotive force in the armature winding 22. The alternating electromotive force generated in the armature winding 22 is rectified to direct current through the rectifier 50 and then supplied to the battery. As a result, the rotating electrical machine 1 functions as a generator.

In the rotor 30 of the rotating electrical machine 1, the permanent magnets 34 are respectively disposed in the gaps 38 between the first claw-shaped magnetic pole portion 37-1 and the second claw-shaped magnetic pole portion 37-2 that are adjacent in the circumferential direction. The circumferential side surface of the claw-shaped magnetic pole part 37 and the corresponding circumferential side surface of the permanent magnet 34 are opposed to each other in the circumferential direction. Hereinafter, the circumferential side surface of the claw-shaped magnetic pole part 37 is referred to as an opposing surface 37a, and the circumferential side surface of the permanent magnet 34 is referred to as an opposing surface 34a.

In the rotor 30, the magnetic resistance between each pair of claw-shaped magnetic pole portions 37 facing each other in the circumferential direction and the permanent magnet 34 is larger at a radially outer position closer to the stator 20 than a radially inner position far from the stator 20. The change in the radial direction position of the magnetic resistance in the rotor 30 is caused by the distance (specifically, the distance between the opposing surface 37a of each pair of claw-shaped magnetic pole portions 37 and the opposing surface 34a of the permanent magnet 34 facing each other in the circumferential direction. This is realized by changing the circumferential distance or the opposing distance) according to the radial position. Specifically, as shown in FIG. 5, the distance is longer at a radially outer position closer to the stator 20 than a radially inner position far from the stator 20.

The opposed surface 34a of the permanent magnet 34 is formed in a substantially flat shape. On the other hand, the opposing surface 37a of the claw-shaped magnetic pole part 37 is formed so as to have irregularities that make the distance from the opposing surface 34a of the permanent magnet 34 non-uniform from the radially inner side to the radially outer side. That is, the claw-shaped magnetic pole part 37 has a recessed part 37b that is recessed in the circumferential direction at a radially outer position of the opposing surface 37a. The recessed portion 37b is formed in a shape in which a part of the facing surface 37a of the claw-shaped magnetic pole portion 37 that is substantially parallel to the facing surface 34a of the permanent magnet 34 is cut out in the circumferential direction. In addition, the site | part located inside radial direction among the opposing surfaces of the nail | claw-shaped magnetic pole part 37 may be formed in substantially planar shape. A distance L1 between a portion located on the radially outer side of the facing surface 37a and the facing surface 34a of the permanent magnet 34 is a distance L2 between a portion located on the radially inner side of the facing surface 37a and the facing surface 34a of the permanent magnet 34. Larger than

The distance between the facing surface 37a of the claw-shaped magnetic pole portion 37 and the facing surface 34a of the permanent magnet 34 is preferably gradually increased from the radially inner side to the radially outer side. As long as it is long as a whole, there are locally included portions that become shorter from the radially inner side to the radially outer side, such as uneven portions for preventing varnish flow and fixing the permanent magnet 34 or the magnet holder 39. Also good. In addition, the distance between the opposing

surfaces

37a and 34a in the recess 37b is preferably gradually increased from the radially inner side to the radially outer side. A portion that becomes shorter from the inner side in the direction to the outer side in the radial direction may be included locally.

As described above, the distance L1 between the portion (indented portion 37b) located on the radially outer side of the opposing surface 37a of the claw-shaped magnetic pole portion 37 in the rotor 30 and the opposing surface 34a of the permanent magnet 34 is the diameter of the opposing surface 37a. If the distance L2 between the portion located on the inner side in the direction and the facing surface 34a of the permanent magnet 34 is larger, the gap in the circumferential direction between the claw-shaped magnetic pole portion 37 and the permanent magnet 34 is more radially outward than the radially inner side. growing. In this case, the magnetic resistance against the magnetic flux flowing in the circumferential direction between the claw-shaped magnetic pole portion 37 and the permanent magnet 34 is increased by the larger gap at the radially outer position than at the radial inner position. The magnetic flux flowing in the circumferential direction between the magnet and the permanent magnet 34 is less likely to flow on the radially outer side and more easily flows on the radially inner side.

In the comparative example in which the magnetic resistance against the magnetic flux flowing in the circumferential direction between the claw-shaped magnetic pole portion 37 and the permanent magnet 34 is uniform regardless of the radial position, the magnetic field is generated by the excitation magnetic field generated in the armature winding 22 of the stator 20. The claw-shaped magnetic pole portion 37 (specifically, the first claw-shaped magnetic pole portion 37-1 that is magnetized to the N pole) from the radially inner end of the stator 20 (specifically, its teeth) through the air gap. ), The following inconvenience occurs. Specifically, the radial direction close to the stator 20 where the distance until the magnetic flux flowing in the claw-shaped magnetic pole portion 37 reaches the permanent magnet 34 is the shortest in the facing surface 37a facing the permanent magnet 34 thereafter. It tends to concentrate on the outer part, and easily flows into the opposing surface 34a of the permanent magnet 34 through the gap 38 from the radially outer part of the opposing surface 37a. Then, the magnetic flux flows through the radially outer portion of the permanent magnet 34 to the adjacent claw-shaped magnetic pole portion 37 (specifically, the second claw-shaped magnetic pole portion 37-2 magnetized to the S pole), and then the stator. Return to 20. For this reason, in this comparative example, the radially outer portion of the permanent magnet 34 is affected by a demagnetizing field (specifically, the above-described excitation magnetic field) as compared with other portions (specifically, the radially inner portion). Since the operating point on the demagnetizing curve at the radially outer portion of the permanent magnet 34 is likely to be lower than the knickpoint, and the operating point is lower than the knickpoint as shown in FIG. In particular, the radially outer portion of the permanent magnet 34 is greatly demagnetized.

On the other hand, in the rotor 30 according to the present embodiment, the magnetic flux generated by the excitation magnetic field generated in the armature winding 22 of the stator 20 causes the air gap from the radial inner end of the stator 20 (specifically, its teeth). When the magnetic flux flows to the claw-shaped magnetic pole portion 37 via the magnetic field, the magnetic flux hardly flows on the radially outer side where the recessed portion 37b exists in the facing surface 37a facing the permanent magnet 34, and the radially inner side where the recessed portion 37b does not exist. It becomes easy to flow. In this case, the magnetic field that has flowed to the claw-shaped magnetic pole portion 37 is guided to a portion radially inward of the claw-shaped magnetic pole portion 37, and the demagnetizing field (specifically, the flow from the facing surface 37a to the permanent magnet 34 side) , The magnetic flux generated by the excitation magnetic field) is dispersed over the entire length in the radial direction of the facing surface 37a.

For this reason, it is possible to suppress a large demagnetizing field from acting on the permanent magnet 34 locally (specifically, radially outward near the stator 20), and the influence of the demagnetizing field received by the permanent magnet 34 is suppressed. 34 can be made uniform over the entire length in the radial direction. In this case, as shown in FIG. 7, the operating point on the demagnetization curve at the radially outer portion of the permanent magnet 34 is suppressed from falling below the knick point. Therefore, in the rotor 30 according to the present embodiment, local demagnetization of the permanent magnet 34 can be prevented, and the demagnetization resistance performance of the permanent magnet 34 can be improved.

In this embodiment, magnetization of the rotor 30 is performed according to the following procedure. First, the field core 31 including the boss portion 35, the disk portion 36, and the claw-shaped magnetic pole portion 37 is assembled to the rotating shaft 80 (step S100 shown in FIG. 8). Thereafter, the permanent magnet 34 before magnetization is assembled to the field core 31 (step S110). The assembly of the non-magnetized permanent magnet 34 is performed for each gap 38 between the two claw-shaped magnetic pole portions 37-1 and 37-2 of the field core 31. The assembly of the permanent magnet 34 is performed by inserting the permanent magnet 34 in the axial direction from one axial end of the field core 31 in a state where the permanent magnet 34 is held by the magnet holder 39. Then, with the rotor 30 facing the stator 20 through an air gap in the radial direction or set in the magnetizing device, the armature winding 22 of the stator 20 or the magnetizing device The permanent magnet 34 is magnetized by a magnetic field generated by flowing a magnetizing current through the exciting winding (step S120).

In the configuration in which the permanent magnet 34 is magnetized in such a state that the permanent magnet 34 is incorporated in the rotor 30, the magnetic flux generated by the magnetizing magnetic field is claw-shaped magnetic pole portion facing the permanent magnet 34 in the same manner as the magnetic flux generated by the demagnetizing field. Of the opposed surfaces 37a of 37, it is difficult to flow on the radially outer side where the recessed portion 37b exists, and it becomes easier to flow on the radially inner side where the recessed portion 37b does not exist. In this case, the magnetic flux generated by the magnetizing magnetic field that has flowed to the claw-shaped magnetic pole portion 37 is guided to a more radially inner portion of the claw-shaped magnetic pole portion 37 and flows out from the facing surface 37a toward the permanent magnet 34. Is dispersed over the entire length in the radial direction of the facing surface 37a. Therefore, according to the present embodiment, the magnetization magnetic field acting on the permanent magnet 34 can be made uniform over the entire radial length of the permanent magnet 34. As a result, it is possible to prevent the permanent magnet 34 from being unevenly magnetized in the radial direction.

Further, in the rotor 30 of the rotating electrical machine 1, the claw-shaped magnetic pole part 37 has the above-described recessed part 37 b and the protruding part 37 c. Each protrusion 37c protrudes outward in the circumferential direction on the radially outer side of the corresponding recess 37b. The front end side of each protrusion 37c is located on the radially outer side of the corresponding permanent magnet 34 and faces the corresponding permanent magnet 34 in the radial direction. Each protrusion 37c has a function of preventing the corresponding permanent magnet 34 from coming out radially outward.

As described above, each permanent magnet 34 is held by the magnet holder 39. As shown in FIGS. 9 and 10, the magnet holder 39 is formed in a U-shaped cross section that can cover the permanent magnet 34. The magnet holder 39 extends in the axial direction (more precisely, a direction oblique to the axial direction). The magnet holder 39 has a function of restricting the permanent magnet 34 from moving in the radial direction with respect to the claw-shaped magnetic pole portion 37 and moves the permanent magnet 34 in the circumferential direction with respect to the claw-shaped magnetic pole portion 37. It has a function to regulate. The magnet holder 39 may be configured to have a function of restricting the permanent magnet 34 from moving in the axial direction with respect to the claw-shaped magnetic pole portion 37. The magnet holder 39 has one bottom portion 39a, a pair of side wall portions 39b, and a pair of locking portions 39c.

The bottom 39a extends in the axial direction and the circumferential direction. Further, the bottom 39 a abuts against the radially inner end surface of the permanent magnet 34 to hold the permanent magnet 34. The permanent magnet 34 is sandwiched between the bottom 39 a of the magnet holder 39 and the protruding portion 37 c of the claw-shaped magnetic pole portion 37, thereby being interfered with the magnet holder 39 and the claw-shaped magnetic pole portion 37 in the radial direction. Thereby, the movement of the permanent magnet 34 in the radial direction is restricted.

The side wall 39b is erected radially outward from both ends in the circumferential direction of the bottom 39a. Further, the side wall portion 39b abuts on both end surfaces in the circumferential direction of the permanent magnet 34 to hold the permanent magnet 34. The permanent magnet 34 is interfered with the magnet holder 39 in the circumferential direction by being sandwiched between the pair of side wall portions 39 b of the magnet holder 39. The pair of side wall portions 39b formed at both ends in the circumferential direction of the bottom portion 39a are separated by the same distance as the separation distance between the two claw-shaped magnetic pole portions 37 adjacent in the circumferential direction (that is, the circumferential size of the gap 38). Yes. For this reason, the magnet holder 39 interferes with the claw-shaped magnetic pole portion 37 in the circumferential direction. Thereby, the movement to the circumferential direction with respect to the nail | claw-shaped magnetic pole part 37 of the permanent magnet 34 is controlled.

The locking portions 39c extend from the radially outer ends of the corresponding side wall portions 39b outward in the circumferential direction. The engaging portions 39c are flange-shaped and are respectively accommodated in the recessed portions 37b of the two claw-shaped magnetic pole portions 37 adjacent in the circumferential direction, and the wall surfaces of the claw-shaped magnetic pole portions 37 forming the recessed portions 37b and Locked to the protrusion 37c. When the locking portions 39c corresponding to the respective side wall portions 39b are respectively housed and locked in the recess portions 37b of the claw-shaped magnetic pole portions 37, the magnet holder 39 of the claw-shaped magnetic pole portions 37 that form the recess portions 37b. It is positioned (fixed) with respect to the claw-shaped magnetic pole portion 37 by a frictional force between the wall surface and the protruding portion 37c. Thereby, the permanent magnet 34 held by the magnet holder 39 is reliably restricted from moving with respect to the claw-shaped magnetic pole portion 37.

As described above, the movement of the magnet holder 39 and the permanent magnet 34 held by the magnet holder 39 with respect to the claw-shaped magnetic pole portion 37 can be restricted. For this reason, it is possible to greatly reduce the occurrence of vibration and peeling of the permanent magnet 34 due to the demagnetizing field, and the occurrence of cracking or chipping due to the shock magnetic field when the permanent magnet 34 is magnetized. Further, the movement restriction of the magnet holder 39 and the permanent magnet 34 with respect to the claw-shaped magnetic pole part 37 can be performed by using the recessed part 37 b formed in the claw-shaped magnetic pole part 37. For this reason, the claw-shaped magnetic pole portion 37 is used to prevent a local demagnetization of the permanent magnet 34 from occurring in the recess of the claw-shaped magnetic pole portion 37 necessary for accommodating a part of the magnet holder 39 and realizing the movement restriction thereof. It is possible to eliminate the need for providing separately from the depressions 37b formed in the first and second depressions 37b, and the functions of both depressions can be shared by one depression 37b. Thereby, simplification of the shape of the claw-shaped magnetic pole part 37 and facilitation of molding can be achieved.

In this embodiment, the magnet holder 39 is formed of a soft magnetic material. Therefore, the magnet holder 39, which is a magnetic body, is disposed over the substantially entire radial direction between the permanent magnet 34 held by the magnet holder 39 and the claw-shaped magnetic pole portion 37. As a result, compared to the case where the magnet holder 39 is not present or the magnet holder 39 is formed of a non-magnetic material, the magnetic resistance of the permanent magnet 34 can be lowered and its permeance can be increased. The demagnetizing field of the permanent magnet 34 can be further reduced.

As described above, in this embodiment, the rotor 30 includes a plurality of permanent magnets 34 that are disposed between two claw-shaped magnetic pole portions 37 that are adjacent to each other in the circumferential direction. Therefore, the weight of the rotor 30 increases by the amount of the permanent magnet 34. When the weight of the rotor 30 increases, the centrifugal force generated when the rotor 30 rotates increases, so that the strength of the rotor 30 can decrease. However, in the present embodiment, the rotor 30 further includes a cylindrical iron core member 33 disposed on the radially outer side of the claw-shaped magnetic pole portion 37 so as to cover the outer peripheral surface thereof. Since the plurality of claw-shaped magnetic pole portions 37 arranged in the circumferential direction are mechanically connected to each other by the iron core member 33, even if the centrifugal force acting on the rotor 30 increases with the weight increase by the permanent magnet 34, Deformation of the claw-shaped magnetic pole portion 37 can be suppressed, and a decrease in strength can be suppressed.

As described above, in the present embodiment, the rotating electrical machine 1 includes the stator 20 having the annular stator core 21 and the armature winding 22 wound around the stator core 21, and the stator 20 on the radially inner side of the stator 20. And a rotor 30 disposed to face each other in the radial direction. The rotor 30 includes a field core 31, a field winding 32, and a plurality of permanent magnets 34. The field core 31 includes a cylindrical boss portion 35 and a plurality of claw-shaped magnetic pole portions 37 that are arranged on the radially outer side of the boss portion 35 and in which magnetic poles having different polarities are alternately formed in the circumferential direction. The field winding 32 is wound around the outer periphery of the boss portion 35 and generates a magnetomotive force when energized. Each permanent magnet 34 is disposed between a pair of claw-shaped magnetic pole portions 37-1 and 37-2 adjacent in the circumferential direction so that the easy axis of magnetization is directed in the circumferential direction, and by the magnetomotive force of the field winding 32. The magnetic poles are formed so as to coincide with the polarities appearing on the pair of claw-shaped magnetic pole portions 37-1 and 37-2. Further, the magnetic resistance between each pair of claw-shaped magnetic pole portions 37 and the permanent magnet 34 facing each other in the circumferential direction is larger at a radially outer position closer to the stator 20 than a radially inner position far from the stator 20. Specifically, the distance between the opposed surfaces of each pair of claw-shaped magnetic pole portions 37 and the permanent magnet 34 facing each other in the circumferential direction is longer at the radially outer position closer to the stator 20 than the radially inner position far from the stator 20. .

According to the above configuration, the magnetic flux flowing in the circumferential direction between the claw-shaped magnetic pole portion 37 and the permanent magnet 34 is difficult to flow on the radially outer side and easily flows on the radially inner side. Therefore, the magnetic flux caused by the exciting magnetic field generated in the armature winding 22 of the stator 20 that flows from the stator 20 to the claw-shaped magnetic pole portion 37 is guided to the radially inner portion of the claw-shaped magnetic pole portion 37 and is claw-shaped. The magnetic flux flowing out from the magnetic pole part 37 to the permanent magnet 34 is dispersed over the entire length in the radial direction of the facing part. Thereby, the influence of the demagnetizing field (the excitation magnetic field) received by the permanent magnet 34 can be made uniform over the entire radial length of the permanent magnet 34. Therefore, local demagnetization of the permanent magnet 34 can be prevented, and its demagnetization resistance can be improved.

In this embodiment, the claw-shaped magnetic pole part 37 has a recessed part 37b that is recessed in the circumferential direction at a radially outer position of the facing surface 37a. According to this configuration, the distance between the opposed surfaces of each pair of claw-shaped magnetic pole portions 37 and the permanent magnet 34 facing each other in the circumferential direction can be made longer at the radially outer position than at the radially inner position.

In this embodiment, the rotor 30 has a magnet holder 39 that holds a permanent magnet 34 that is partly housed in the recess 37 b of the claw-shaped magnetic pole part 37. According to this configuration, a portion of the magnet holder 39 that holds the permanent magnet 34 can be accommodated in the recess 37 b of the claw-shaped magnetic pole portion 37, and the permanent magnet 34 is positioned with respect to the claw-shaped magnetic pole portion 37. (Fixed).

In the present embodiment, the claw-shaped magnetic pole portion 37 has a recess portion 37b and a protrusion portion 37c that protrudes in the circumferential direction on the radially outer side of the corresponding recess portion 37b. The magnet holder 39 is locked to the wall surface of the claw-shaped magnetic pole part 37 that forms the corresponding hollow part 37b and the corresponding projecting part 37c. According to this configuration, the movement of the magnet holder 39 and thus the permanent magnet 34 held by the magnet holder 39 can be restricted with respect to the claw-shaped magnetic pole portion 37. For this reason, it is possible to reduce the occurrence of vibration or peeling of the permanent magnet 34 due to the demagnetizing field, or the occurrence of cracks or chipping due to the shock magnetic field when the permanent magnet 34 is magnetized.

In this embodiment, the magnet holder 39 is made of a magnetic material. According to this configuration, since the magnet holder 39 which is a magnetic body is disposed between the permanent magnet 34 and the claw-shaped magnetic pole portion 37 over substantially the entire radial direction, the magnetic resistance of the entire permanent magnet 34 can be reduced. And the permeance can be increased. For this reason, the demagnetizing field of the permanent magnet 34 can be further reduced.

In the present embodiment, the permanent magnet 34 is magnetized while being assembled between the claw-shaped magnetic pole portions 37 adjacent in the circumferential direction. According to this configuration, the magnetic flux generated by the magnetizing magnetic field flowing in the circumferential direction between the claw-shaped magnetic pole portion 37 and the permanent magnet 34 is difficult to flow on the radially outer side and easily flows on the radially inner side. Therefore, the magnetic flux generated by the magnetized magnetic field that has flowed to the claw-shaped magnetic pole portion 37 is guided to the radially inner portion of the claw-shaped magnetic pole portion 37, and the magnetic flux generated by the magnetized magnetic field that flows from the claw-shaped magnetic pole portion 37 to the permanent magnet 34. Is dispersed over the entire length in the radial direction of the opposing portion. Thereby, the magnetizing magnetic field acting on the permanent magnet 34 can be made uniform over the entire radial length of the permanent magnet 34. As a result, it is possible to prevent the permanent magnet 34 from being unevenly magnetized in the radial direction.

(Modification)
In the above embodiment, the distance between the facing surface 37a of the claw-shaped magnetic pole portion 37 and the facing surface 34a of the permanent magnet 34 facing in the circumferential direction is a radially outer position closer to the stator 20 than a radially inner position far from the stator 20. In order to increase the length, a notch-shaped depression 37b is provided at a radially outer position on the opposing surface 37a of the claw-shaped magnetic pole portion 37. However, the present disclosure is not limited to this. The claw-shaped magnetic pole part 37 may be formed in a tapered shape so that the distance from the permanent magnet 34 gradually increases from the radially inner side to the radially outer side.

In the above embodiment, the claw-shaped magnetic pole portion 37 of the rotor 30 has the recessed portion 37b and the protruding portion 37c protruding in the circumferential direction on the radially outer side of the corresponding recessed portion 37b. And the latching | locking part 39c of the magnet holder 39 holding the permanent magnet 34 is latched by the wall surface of the nail | claw-shaped magnetic pole part 37 which forms the corresponding hollow part 37b, and the corresponding protrusion part 37c, and the corresponding hollow part 37b. It is inserted in. However, the present disclosure is not limited to this. For example, as shown in FIG. 11, the recess 37b of the claw-shaped magnetic pole part 37 is formed in a tapered shape at the corner where the outer peripheral surface and the circumferential side surface of the claw-shaped magnetic pole part 37 intersect. The magnet holder 39 does not have the protruding portion 37c and is formed in a space formed by the inner peripheral surface of the cylindrical iron core member 33 and the wall surface of the claw-shaped magnetic pole portion 37 that forms the recessed portion 37b. It is good also as being contact | abutted to those surfaces and fitting and fixing. Also in this modification, the magnet holder 39 is positioned with respect to the claw-shaped magnetic pole part 37 by the frictional force between the wall surface of the claw-shaped magnetic pole part 37 and the inner peripheral surface of the iron core member 33 that form the corresponding hollow part 37b. Since it is (fixed), it is possible to restrict the movement of the permanent magnet 34 with respect to the claw-shaped magnetic pole portion 37 and the iron core member 33 using the magnet holder 39. For this reason, it is possible to reduce the occurrence of vibration or peeling of the permanent magnet 34 due to the demagnetizing field, or the occurrence of cracks or chipping due to the shock magnetic field when the permanent magnet 34 is magnetized.

In the above embodiment, the locking portion 39c of the magnet holder 39 is accommodated in the recess 37b of the claw-shaped magnetic pole portion 37, and the wall surface and the protruding portion 37c of the claw-shaped magnetic pole portion 37 forming the recess 37b. It is locked to. However, the present disclosure is not limited to this. A claw-shaped magnetic pole portion that forms a recess 37b in the locking portion 39c of the magnet holder 39 while sandwiching the permanent magnet 34 between the bottom portion 39a of the magnet holder 39 and the protruding portion 37c of the claw-shaped magnetic pole portion 37 or the iron core member 33. It is good also as latching only to the part which faced the radial direction outward among 37 wall surfaces. In order to realize this structure, the distance between the bottom 39a and the locking portion 39c of the magnet holder 39, that is, the height of the side wall 39b and the radial height of the permanent magnet 34 should be set to satisfy a predetermined relationship. Good.

In the above-described embodiment, the depression 37b is provided at the radially outer position on the facing surface 37a of the claw-shaped magnetic pole portion 37, and the facing surface 37a of the claw-shaped magnetic pole portion 37 and the facing surface 34a of the permanent magnet 34 facing each other in the circumferential direction. Is longer at the radially outer position closer to the stator 20 than at the radially inner position far from the stator 20, so that the magnetoresistance between the claw-shaped magnetic pole portion 37 and the permanent magnet 34 facing in the circumferential direction is increased. It is larger at a radially outer position closer to the stator 20 than a radially inner position far from the stator. However, the present disclosure is not limited to this. A notch-like depression may be provided at a radially outer position on the facing surface 34a of the permanent magnet 34 to realize the above-described distance relationship and magnetoresistance relationship. In addition, as shown in FIG. 12, the permanent magnet 34 may be formed in a tapered shape so that the distance from the claw-shaped magnetic pole portion 37 gradually increases from the radially inner side to the radially outer side.

In the above embodiment, the claw-like shape facing in the circumferential direction is set to increase the magnetic resistance between the claw-shaped magnetic pole part 37 and the permanent magnet 34 facing in the circumferential direction at the radial outside position from the radial inside position. The distance between the facing surface 37a of the magnetic pole part 37 and the facing surface 34a of the permanent magnet 34 is longer at the radially outer position than at the radially inner position. However, the present disclosure is not limited to this. In order to realize the above-described magnetic resistance relationship, the magnetic permeability of the facing portion between the claw-shaped magnetic pole portion 37 and the permanent magnet 34 facing in the circumferential direction may be made smaller at the radially outer position than at the radially inner position. . Also in this modification, the same effect as the above-described embodiment can be obtained.

For example, the opposing surface 37a of the claw-shaped magnetic pole part 37 and the opposing surface 34a of the permanent magnet 34 are both formed in a substantially planar shape, and the distance between the opposing

surfaces

37a, 34a facing each other in the circumferential direction is set to a diameter regardless of the radial position. The magnetic permeability of at least one opposing portion of the claw-shaped magnetic pole portion 37 and the permanent magnet 34 is made constant at the radially outer position closer to the stator 20 than the radially inner position far from the stator 20. It is good also as making it small.

Further, for example, as shown in FIG. 13, the recess 37b of the claw-shaped magnetic pole part 37 is formed in a tapered shape at a corner where the outer peripheral surface and the circumferential side surface of the claw-shaped magnetic pole part 37 intersect, and is opposed in the circumferential direction. The distance between the facing surface 37a of the claw-shaped magnetic pole portion 37 and the facing surface 34a of the permanent magnet 34 is made longer at the radially outer position than the radially inner position, and the recess 37b has a larger distance than the claw-shaped magnetic pole portion 37. Alternatively, the magnetic body 90 made of a magnetic material having a low magnetic permeability may be press-fitted or filled by pouring the magnetic material. The magnetic material having a smaller magnetic permeability than the claw-shaped magnetic pole portion 37 may be, for example, soft ferrite. Further, in this press-fitting and filling molding, after the engaging part 39c of the magnet holder 39 is accommodated and mounted in the recess 37b, a rod-like magnetic body 90 is press-fitted into the gap of the recess 37b or the magnetic material is used. It may be cast and filled.

Further, for example, the opposing surface 37a of the claw-shaped magnetic pole portion 37 and the opposing surface 34a of the permanent magnet 34 are both formed in a substantially planar shape, and the distance between the opposing

surfaces

37a, 34a facing in the circumferential direction is independent of the radial position. The magnetic permeability of the magnet holder 39 disposed between the

opposed surfaces

37a and 34a is made constant from the radially inner side to the radially outer side at a radially outer position closer to the stator 20 than the radially inner position far from the stator 20. It is good also as making it small.

In the above embodiment, after the permanent magnet 34 is incorporated into the rotor 30, a magnetic pole is formed on the permanent magnet 34 so as to coincide with the polarity appearing on the claw-shaped magnetic pole portion 37 by the magnetomotive force of the field winding 32. Do magnetism. According to this configuration, since all the permanent magnets 34 arranged in the circumferential direction can be magnetized simultaneously, the permanent magnet 34 can be easily magnetized.

However, the present disclosure is not limited to this. Each permanent magnet 34 may be individually magnetized before being incorporated into the rotor 30, and each permanent magnet 34 may be incorporated into the rotor 30 after being magnetized.

It should be noted that the present disclosure is not limited to the above-described embodiments and modifications, and various modifications can be made without departing from the spirit of the present disclosure. For example, the rotor 30 and thus the rotating electrical machine 1 may be configured by combining the above-described embodiment and each modification.

1: rotating electric machine, 20: stator, 21: stator core, 22: armature winding, 30: rotor, 31: field core, 32: field winding, 33: cylindrical iron core member, 34: permanent magnet, 34a: opposing surface of permanent magnet, 35: boss portion, 36: disk portion, 37: claw-shaped magnetic pole portion, 37a: opposing surface of claw-shaped magnetic pole portion, 37b: recessed portion, 37c: protruding portion, 38: gap, 39 : Magnet holder.

Claims

An annular stator core (21) and a stator (20) having an armature winding (22) wound around the stator core, and arranged radially opposite the stator on the radially inner side of the stator A rotating electrical machine (1) comprising a rotor (30),
The rotor is
A field core (37) having a cylindrical boss portion (35) and a plurality of claw-shaped magnetic pole portions (37) arranged on the radially outer side of the boss portion and formed with magnetic poles having different polarities alternately in the circumferential direction. 31) and
A field winding (32) wound around the outer periphery of the boss portion and generating a magnetomotive force by energization;
Between each of the two claw-shaped magnetic pole portions adjacent to each other in the circumferential direction, the magnetization easy axis is arranged in the circumferential direction, and appears in the two claw-shaped magnetic pole portions by the magnetomotive force of the field winding. A plurality of permanent magnets (34) having magnetic poles formed to match the polarity;
Have
A rotating electrical machine in which a magnetic resistance between each pair of claw-shaped magnetic pole portions facing each other in the circumferential direction and the permanent magnet is larger at a radially outer position closer to the stator than a radially inner position far from the stator.
2. The rotating electrical machine according to claim 1, wherein a distance between opposing surfaces of each pair of the claw-shaped magnetic pole portions facing each other in the circumferential direction and the permanent magnet is longer at the radially outer position than at the radially inner position.
In each pair of the claw-shaped magnetic pole portions and the permanent magnets facing each other in the circumferential direction, at least one of the claw-shaped magnetic pole portions and the permanent magnet is a depression recessed in the circumferential direction at the radially outer position of the facing surface. The rotating electrical machine according to claim 2, comprising a portion (37b).
The recess is provided in the claw-shaped magnetic pole,
The rotating electrical machine according to claim 3, wherein the rotor has a magnet holder (39) for holding the permanent magnet, a part of which is accommodated in the recess.
The claw-shaped magnetic pole part has the recess part and a protrusion part (37c) protruding in the circumferential direction on the radially outer side of the recess part,
5. The rotating electrical machine according to claim 4, wherein the magnet holder is locked to a wall surface of the claw-shaped magnetic pole portion that forms the hollow portion and the protruding portion.
The rotor has a cylindrical iron core member (33) disposed on the radially outer side of the claw-shaped magnetic pole portion so as to cover the outer peripheral surface of the claw-shaped magnetic pole portion,
5. The rotating electrical machine according to claim 4, wherein the magnet holder is fitted and fixed in a space formed by an inner peripheral surface of the iron core member and a wall surface of the claw-shaped magnetic pole portion that forms the hollow portion.
The rotating electric machine according to any one of claims 4 to 6, wherein the magnet holder is made of a magnetic material.
8. The magnetic permeability of at least one of the facing portions of each pair of the claw-shaped magnetic pole portions facing each other in the circumferential direction and the permanent magnet is smaller at the radially outer position than at the radially inner position. The rotating electrical machine according to claim 1.
The rotating electrical machine according to any one of claims 1 to 8, wherein the permanent magnet is magnetized in a state of being assembled between the claw-shaped magnetic pole portions adjacent in the circumferential direction.