JP6737238B2 - Rotating electric machine - Google Patents

Description

The present invention relates to a rotating electric machine including a stator and a rotor.

BACKGROUND ART Conventionally, a rotating electric machine such as a vehicle AC generator including a stator and a rotor is known (for example, Patent Document 1). In the generator described in Patent Document 1, the rotor has 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 of rotation by the field winding. It is a rotor. This rotor is arranged between two claw-shaped magnetic pole portions that are adjacent to each other in the circumferential direction of rotation, and the magnetic poles are formed so as to match the polarities alternately appearing in the claw-shaped magnetic pole portions due to the magnetomotive force of the field winding. It has a magnet. With this permanent magnet, a larger output density can be obtained. In such a generator, the size of the permanent magnet and the shapes of the boss, disk, and claw-shaped magnetic poles of the rotor core of the Lundell-type rotor are optimized for design, which improves the power generation capacity and counteracts it. Achieving compatibility with reduction of electric power.

JP-A-4-255451

In recent years, assuming a case where a rotating electric machine is mounted on a vehicle, for example, a slant nose for reducing vehicle running resistance, a smaller engine room, and the like are accompanied by a space for mounting a vehicle AC generator and a starter. It is being minimized. Since the ability to starter, the highly efficient powering to assist the vehicle in high efficiency operation, and the regenerative ability are added as the ability that is regarded as important in such a situation, the ratio of the ability improvement only to the pure power generation ability is relatively high. Since the field current becomes large in a short period of time, the power generation, torque, and regenerative ability of the generator are attracting attention. When this field current becomes a large current in a short period of time, both the field magnetic field generated by the rotor and the magnetic field generated by the stator wound with the winding are added to the permanent magnet, and the permanent magnet has a strong demagnetizing field. Is added.

Generally, in a rotor of a combined electromagnet/magnet type in which a parallel magnetic circuit having at least two magnetic circuits of a permanent magnet and a magnetic circuit of a field core is formed as in the Lundell type rotor disclosed in Patent Document 1. When the field current becomes large in a short period of time, the permanent magnet simultaneously receives a strong demagnetizing field from the field coil and a strong demagnetizing field received from the stator side exciting coil. When a strong demagnetizing field is applied to the permanent magnet, the permanent magnet may be significantly demagnetized.

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

One aspect of the present invention is a rotating electric machine comprising: an annular stator having an armature winding wound around a stator core; and a rotor arranged to face an inner side in a radial direction of the stator. Is a cylindrical boss portion, and a field core having a plurality of claw-shaped magnetic pole portions arranged radially outside of the boss portion and having magnetic poles of different polarities formed alternately in the circumferential direction of rotation, and the boss. A field winding that is wound around the outer peripheral side of the portion and that generates a magnetomotive force by energization, and an easy axis of magnetization is arranged in the circumferential direction between the claw-shaped magnetic pole portions that are adjacent in the rotational circumferential direction, and has a permanent magnet poles to match the polarities appear alternately on the claw-shaped magnetic pole portions by the magnetomotive force of the field winding is formed, the rotation each other of the permanent magnet and the claw-shaped magnetic pole portions The distance between the facing surfaces facing each other in the circumferential direction is longer at the radially outer position closer to the stator than at the radially inner position far from the stator, and the claw-shaped magnetic pole portion and the permanent magnet rotate relative to each other. magnetic resistance in the direction opposite to the direction, the radial who in the radially outer position than in the inward position rather large, the claw-shaped magnetic pole portions are recessed in the radially outer position of the facing surface recess And the rotor is a rotating electric machine having a magnet holder for holding the permanent magnet, a part of which is housed in the hollow portion .

According to this configuration, the magnetic field flowing in the rotational circumferential direction between the claw-shaped magnetic pole portion and the permanent magnet is hard to flow on the radially outer side and easily flows on the radially inner side. The magnetic field is guided to a portion radially inward of the claw-shaped magnetic pole portion, and the magnetic field flowing out from the claw-shaped magnetic pole portion to the permanent magnet side is dispersed in the entire radial direction of the facing portion. Therefore, the influence of the demagnetizing field on the permanent magnet can be made uniform at the radial position of the permanent magnet. Therefore, local demagnetization of the permanent magnet can be prevented, and its demagnetization resistance performance can be improved.

With this configuration, the gap between the facing surfaces of the claw-shaped magnetic pole portion and the permanent magnet can be made larger at the radially outer position than at the radially inner position. The magnetic resistance at the radially outer position closer to the stator in the direction opposed to the circumferential direction of rotation can be made larger than the magnetic resistance at the radially inner position far from the stator. Therefore, since the influence of the demagnetizing field on the permanent magnet can be made uniform in the radial position of the permanent magnet, it is possible to prevent local demagnetization of the permanent magnet and improve its demagnetization resistance performance. You can

According to this configuration, the distance between the facing surfaces in the portion where the recess is present is made longer than the distance between the facing surfaces in the portion where the recess is not present, and the facing surface between the claw-shaped magnetic pole portion and the permanent magnet is increased. The gap between them can be made larger at the radially outer position than at the radially inner position. Therefore, the magnetic resistance of the claw-shaped magnetic pole portion and the permanent magnet at the radially outer position closer to the stator in the direction opposed to each other in the circumferential direction of rotation can be made larger than the magnetic resistance at the radially inner position far from the stator. it can. Therefore, since the influence of the demagnetizing field on the permanent magnet can be made uniform in the radial position of the permanent magnet, it is possible to prevent local demagnetization of the permanent magnet and improve its demagnetization resistance performance. You can

According to the configuration of this, in a recess portion of the claw-shaped magnetic pole portions, it is possible to receive a portion of the magnet holder for holding the permanent magnets, it is possible to position fixing the permanent magnet against the claw-shaped magnetic pole portions.

The claw-shaped magnetic pole portion includes the recess portion and a protrusion portion that protrudes in the rotation circumferential direction on the outer side in the radial direction of the recess portion, and the magnet holder has an outer surface that forms the recess portion and the outer surface. It may be locked to the protrusion.

According to this configuration, the magnet holder, and thus the permanent magnet held by the magnet holder, can be restricted in movement with respect to the claw-shaped magnetic pole portion. Therefore, 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.

Further , the rotor has a cylindrical magnetic pole iron core arranged radially outside of the claw-shaped magnetic pole portion so as to cover an outer peripheral surface of the claw-shaped magnetic pole portion, and the magnet holder includes an inner portion of the magnetic pole iron core. It may be fitted and fixed in a space formed between a peripheral surface and an outer surface of the claw-shaped magnetic pole portion forming the recess.

According to this structure, 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 magnetic pole core. Therefore, 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. In addition, the depression of the claw-shaped magnetic pole portion required to accommodate a part of the magnet holder and the depression of the claw-shaped magnetic pole portion required to prevent local demagnetization of the permanent magnet can be used together. can do. Therefore, it is possible to simplify the shape of the claw-shaped magnetic pole portion and facilitate the molding. Further, since the magnetic pole iron core is arranged so as to cover the outer peripheral surface of the claw-shaped magnetic pole portion, a plurality of claw-shaped magnetic pole portions arranged in the circumferential direction of rotation can be connected to each other via the magnetic pole iron core. Therefore, even if the centrifugal force acting on the rotor increases as the weight of the permanent magnets increases, the deformation of the claw-shaped magnetic pole portions can be reliably suppressed, and the reduction in strength can be suppressed.

Further , the magnet holder may be made of a magnetic material. According to this structure, since the magnet holder, which is a magnetic body, is arranged between the permanent magnet and the claw-shaped magnetic pole portion over substantially the entire area in the radial direction, the magnetic resistance of the entire permanent magnet can be reduced, and the permeance thereof can be reduced. Can be increased. Therefore, the demagnetizing field of the permanent magnet can be further reduced.

In addition, the magnetic permeability of the facing portions facing each other circumferential direction of rotation of the permanent magnet and the claw-shaped magnetic pole portions, is small Kuteyoi person in the radially outward position than that of the radially inward position.

According to this configuration, the magnetic resistance of the claw-shaped magnetic pole portion and the permanent magnet at the radially outer position closer to the stator in the direction opposed to each other in the circumferential direction of rotation is compared to the magnetic resistance at the radially inner position far from the stator. Can be large. Therefore, since the influence of the demagnetizing field on the permanent magnet can be made uniform in the radial position of the permanent magnet, it is possible to prevent local demagnetization of the permanent magnet and improve its demagnetization resistance performance. You can

The front SL permanent magnet may be magnetized magnets in a state of being assembled between said claw-shaped magnetic pole portion adjacent to the circumferential direction of rotation.

According to this structure, the magnetizing magnetic field flowing in the circumferential direction of rotation between the claw-shaped magnetic pole portion and the permanent magnet is hard to flow on the outer side in the radial direction and easily flows on the inner side in the radial direction. The magnetizing magnetic field is guided to a portion radially inward of the claw-shaped magnetic pole portion, and the magnetizing magnetic field flowing out from the claw-shaped magnetic pole portion toward the permanent magnet is dispersed in the entire radial direction of the facing portion. Therefore, the magnetizing magnetic field received by the permanent magnet can be made uniform at the radial position of the permanent magnet, so that the magnetizing of the permanent magnet can be prevented from becoming non-uniform as a whole.

It is sectional drawing showing the structure of the rotary electric machine which concerns on one Embodiment of this invention. It is a figure when the rotor with which the rotary electric machine of this embodiment is equipped is seen from the radial outside. It is a perspective view of the rotor with which the rotary electric machine of this embodiment is equipped. It is a perspective view in the state where the magnetic pole iron core which covers the perimeter of a claw-shaped magnetic pole part was removed among the rotors with which the rotary electric machine of this embodiment was equipped. It is a figure when the principal part of the rotor with which the rotary electric machine of this embodiment is equipped was seen from an axial direction. It is a figure showing an example of the demagnetization curve which shows the relation between a magnetic field and magnetic flux density when irreversible demagnetization generate|occur|produces in a permanent magnet. It is a figure showing an example of a demagnetization curve showing a relation between a magnetic field and magnetic flux density for explaining a method of setting magnetic resistance of a rotor so that irreversible demagnetization does not occur in a permanent magnet. It is an example of the flowchart showing the assembly procedure of the rotor of the present embodiment. It is a figure when the magnet holder which the rotor of this embodiment has and its periphery are seen from the axial direction. It is a perspective view of the magnet holder which the rotor of this embodiment has. It is the figure when the magnet holder which the rotor of the rotary electric machine which concerns on the modification of this invention has, and its periphery are seen from an axial direction. It is a figure when the principal part of the rotor of the rotary electric machine which concerns on the other modified form of this invention is seen from the axial direction. It is a figure when the principal part of the rotor of the rotary electric machine which concerns on another modification of this invention is seen from the axial direction.

Specific embodiments and modifications of the rotary electric machine according to the present invention will be described below with reference to FIGS. 1 to 13.

First, the configuration of the rotary electric machine 1 according to the embodiment will be described. The rotating electric machine 1 is mounted in, for example, a vehicle, and generates a driving force for driving the vehicle by being supplied with power from a power source such as a battery, and is also supplied with a driving force from an engine of the vehicle. This is a device that generates electric power for charging the battery. The rotary electric machine 1 is a three-phase AC motor generator. As shown in FIG. 1, the rotary electric machine 1 includes a housing 10, a stator 20, a rotor 30, a brush device 40, a rectifying device 50, a voltage regulator 60, and a pulley 70.

The housing 10 is a case member that houses the stator 20 and the rotor 30. The housing 10 supports the rotating shaft 80 fitted to the rotor 30 via a bearing so as to be rotatable about its axis, and also fixes the stator 20.

The stator 20 is a member that generates a magnetic field that rotates the rotor 30 when an electric current flows and also generates a magnetic field by the rotation of the rotor 30 to generate an electromotive force. The stator 20 includes a stator core 21 and an armature winding 22. The stator core 21 is a hollow cylindrical member. The stator core 21 is made of a soft magnetic material such as an electromagnetic steel plate made of iron or silicon steel, and constitutes a part of the magnetic path. The stator core 21 includes an annular portion formed in an annular shape, and a plurality of teeth portions extending inward in the radial direction from an inner surface in the radial direction of the annular portion and arranged at predetermined circumferential angles. , And a slot portion that is vacant between two tooth portions that are adjacent to each other in the circumferential direction of rotation.

The armature winding 22 is wound around the stator core 21. The armature winding 22 has a linear slot housing portion housed in the slot portion of the stator core 21, and a curved coil end portion that projects axially outward from the axial end of the stator core 21. .. The armature windings 22 are polyphase windings (for example, three-phase windings) provided in the number corresponding to the number of phases of the rotary electric machine 1. Each phase winding of the armature winding 22 is connected to the inverter device. The voltage applied to each phase winding is controlled by switching-driving a switching element in the inverter device.

The rotor 30 is disposed to face the stator 20 (specifically, the tips of the teeth) radially inward with a predetermined air gap. That is, the stator 20 and the rotor 30 are arranged to face each other in the radial direction with a predetermined air gap therebetween. The rotor 30 can apply a magnetic field to the armature winding 22 side by rotation. The rotor 30 is a so-called Lundell type rotor. The rotor 30 includes a field core 31, a field winding 32, a magnetic pole tube portion 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 a boss portion 35, a disk portion 36, and a claw-shaped magnetic pole portion 37. The boss portion 35, the disk portion 36, and the claw-shaped magnetic pole portion 37 form a pole core (field iron core). The field core 31 is, for example, forged.

The boss portion 35 is a portion fitted and fixed to the outer peripheral side of the rotary shaft 80. The disk portion 36 is a disk-shaped portion that extends radially outward from the end of the boss portion 35 in the rotation axis direction. The claw-shaped magnetic pole part 37 is a claw-shaped part that is connected to the outer peripheral end of the disk part 36 and extends in the axial direction from the connected part. The claw-shaped magnetic pole portion 37 extends from the connecting portion with the disc portion 36 along the rotation axis direction of the rotation shaft 80. The claw-shaped magnetic pole portion 37 is arranged with a gap radially outward from the boss portion 35. The outer peripheral surface of the claw-shaped magnetic pole portion 37 is formed in a substantially arc shape.

The claw-shaped magnetic pole portion 37 includes a first claw-shaped magnetic pole portion 37-1 and a second claw-shaped magnetic pole portion 37-2 in which magnetic poles having different polarities (specifically, N pole and S pole) are formed. The first claw-shaped magnetic pole portion 37-1 and the second claw-shaped magnetic pole portion 37-2 form a pair of pole cores. The first claw-shaped magnetic pole portions 37-1 and the second claw-shaped magnetic pole portions 37-2 are provided in the same number (e.g., eight) in the circumferential direction of the rotor 30. 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 while being spaced apart from each other with a gap space 38 in the rotation circumferential direction.

The first claw-shaped magnetic pole portion 37-1 and the second claw-shaped magnetic pole portion 37-2 rotate so that the axial root side (or the axial tip side) connected to the disc portion 36 is axially opposite to each other. They are arranged alternately in the circumferential direction. The first claw-shaped magnetic pole portion 37-1 and the second claw-shaped magnetic pole portion 37-2 are magnetized to have different polarities. The first claw-shaped magnetic pole portion 37-1 is connected to the outer peripheral end of the disk portion 36 that extends radially outward from one axial side of the boss portion 35, and extends to the other axial side. The second claw-shaped magnetic pole portion 37-2 is connected to the outer peripheral end of the disc portion 36 that extends radially outward from the other end side in the axial direction of the boss portion 35, and extends to one end side in the axial direction. .. The first claw-shaped magnetic pole portion 37-1 and the second claw-shaped magnetic pole portion 37-2 are formed in a common shape except for the arrangement position and the protruding axial direction.

Each claw-shaped magnetic pole portion 37 is formed so as to have a predetermined width (that is, a circumferential width) in the rotation circumferential direction and a predetermined thickness (that is, a radial thickness) in the radial direction. Each of the claw-shaped magnetic pole portions 37 is formed so that the width in the circumferential direction and the thickness in the radial direction gradually decrease from the root side in the vicinity of the connecting portion with the disc portion 36 to the tip side in the axial direction. .. That is, each claw-shaped magnetic pole portion 37 is formed so as to become thinner in both the circumferential direction of rotation and the radial direction toward the tip end side in the axial direction. It is preferable that each of the claw-shaped magnetic pole portions 37 is formed so as to be bilaterally symmetric with respect to the circumferential direction in the circumferential direction of rotation.

The clearance space 38 is provided between each of the first claw-shaped magnetic pole portions 37-1 and the second claw-shaped magnetic pole portions 37-2 that are adjacent to each other in the rotation circumferential direction. The clearance space 38 extends obliquely in the axial direction, and is inclined at a predetermined angle from the axial end portion to the opposite axial end portion with respect to the rotation axis of the rotor 30. Each clearance space 38 has a size (that is, a dimension) in the circumferential direction of rotation that hardly changes in accordance with an axial position, that is, a circumferential dimension thereof is constant or a very small amount including the constant value. It is set to be maintained within a certain range. A permanent magnet 34 is arranged in each gap space 38.

The field winding 32 is arranged in a radial gap between the boss portion 35 and the claw-shaped magnetic pole portion 37. The field winding 32 is wound around the boss portion 35 around the rotation axis on the outer peripheral side of the boss portion 35. The field winding 32 is a coil member that generates a magnetic flux in the field core 31 by applying a direct current to generate a magnetomotive force. The magnetic flux generated by the field winding 32 is guided to the claw-shaped magnetic pole portion 37 via the boss portion 35 and the disc portion 36. 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 portion 37-1 to the N pole and the second claw-shaped magnetic pole portion 37-2 to the S pole by the generated magnetic flux.

As shown in FIGS. 2 and 3, the magnetic pole tube portion 33 has its claw radially outward of the claw-shaped magnetic pole portion 37 (that is, the first claw-shaped magnetic pole portion 37-1 and the second claw-shaped magnetic pole portion 37-2). Is a substantially cylindrical member arranged so as to cover the outer peripheral surface of the magnetic pole portion 37. The magnetic pole tube portion 33 has an axial length of about the distance from the connecting portion of the claw-shaped magnetic pole portion 37 with the disk portion 36 to the axial tip of the claw-shaped magnetic pole portion 37. The magnetic pole tube portion 33 is a thin skin member having a predetermined thickness in the radial direction. The radial thickness is, for example, about 0.6 mm to 1.0 mm, which can achieve both mechanical strength and magnetic performance of the rotor 30. The magnetic pole tube portion 33 is arranged so as to face the circular arc surface of the claw-shaped magnetic pole portion 37, and is in contact with the claw-shaped magnetic pole portion 37. The magnetic pole tube portion 33 is arranged so as to close the gap space 38 between the first claw-shaped magnetic pole portion 37-1 and the second claw-shaped magnetic pole portion 37-2 which are adjacent to each other in the circumferential direction of rotation, on the radially outer side. And the claw-shaped magnetic pole portions 37-1 and 37-2 are magnetically connected to each other.

The magnetic pole tube portion 33 is a magnetic pole core formed of a metal material having soft magnetic characteristics. The magnetic pole cylinder portion 33 may be a pipe-shaped member formed in a cylindrical shape, a laminated member in which a plurality of punched thin plate members and the like are laminated in the axial direction, or a wire member wound or rolled and fitted. .. The magnetic pole tube portion 33 is fixed to the claw-shaped magnetic pole portion 37 by shrink fitting, press fitting, welding, or a combination thereof. The thin plate-shaped, linear, or strip-shaped member that constitutes the magnetic pole tube portion 33 is preferably a square member having a rectangular cross section from the viewpoint of strength and magnetic performance, but a round wire or a curved corner portion. May be.

The magnetic pole cylinder portion 33 has a function of smoothing the outer peripheral surface of the rotor 30 and reducing wind noise caused by the unevenness formed on the outer peripheral surface of the rotor 30. In addition, the magnetic pole tube portion 33 connects the plurality of claw-shaped magnetic pole portions 37 arranged in the circumferential direction of rotation to each other, so that when the centrifugal force acts, the respective claw-shaped magnetic pole portions 37 are deformed (in particular, radially outwardly deformed). ) Has a function to suppress.

The permanent magnet 34 is housed inside the magnetic pole tube portion 33 in the radial direction. The permanent magnet 34 has a clearance space between the two claw-shaped magnetic pole portions 37 that are adjacent to each other in the circumferential direction of rotation, that is, between the pair of the first claw-shaped magnetic pole portion 37-1 and the second claw-shaped magnetic pole portion 37-2. 38 is a magnet between magnetic poles arranged so as to fill up 38. The permanent magnets 34 are arranged in each of the gap spaces 38, and the permanent magnets 34 are provided in the same number as the number of the gap spaces 38.

Each permanent magnet 34 is formed in a substantially rectangular parallelepiped shape. The permanent magnets 34 are arranged in a state of extending obliquely in the axial direction so as to be inclined in the circumferential direction on the surface side of the claw-shaped magnetic pole portion 37. The permanent magnet 34 has a function of reducing leakage of magnetic flux between the two claw-shaped magnetic pole portions 37 adjacent to each other in the circumferential direction of rotation and strengthening the magnetic flux between the claw-shaped magnetic pole portion 37 and the stator core 21 of the stator 20. ing.

The permanent magnets 34 are arranged so that magnetic poles are formed so as to reduce the leakage magnetic flux between two claw-shaped magnetic pole portions 37 that are adjacent in the rotation circumferential direction, that is, the easy axis of magnetization is oriented in the circumferential direction. .. Specifically, in the permanent magnet 34, the magnetic pole on the surface in the rotation circumferential direction facing the first claw-shaped magnetic pole portion 37-1 magnetized to the N pole becomes the N pole, and the second magnet magnetized to the S pole. The magnetic pole on the surface in the rotational circumferential direction facing the claw-shaped magnetic pole portion 37-2 is formed and arranged so as to be the S pole. The permanent magnet 34 is incorporated in the rotor 30, and is magnetized in a state of being assembled between the two claw-shaped magnetic pole portions 37-1 and 37-2 that are adjacent to each other in the rotation circumferential direction.

The permanent magnet 34 is held by the magnet holder 39 and is integrated with the magnet holder 39. The permanent magnet 34 is held and fixed to the rotor 30 by using a magnet holder 39. The permanent magnet 34 is held and fixed to the rotor 30 in a state in which all or part of the permanent magnet 34 is covered by the magnet holder 39. The magnet holder 39 is formed of a so-called soft magnetic material that is attracted by a magnet such as iron. For this reason, when the rotating electric machine 1 is not loaded, the magnet holder 39 can short-circuit the magnetic flux generated by the permanent magnet 34, so that the occurrence of back electromotive force can be suppressed, and the damage to the equipment of the load circuit can be suppressed. You can

The brush device 40 has a slip ring 41 and a brush 42. The slip ring 41 is fixed to one end of the outer peripheral surface of the rotary shaft 80 in the axial direction. The slip ring 41 has a function of supplying a direct current to the field winding 32 of the rotor 30. Two brushes 42 are provided as a pair, and are held by a brush holder mounted and fixed to the housing 10. The brush 42 is arranged in a state of being pressed toward the rotary shaft 80 by a spring so that the tip on the radially inner side slides on the surface of the slip ring 41. The brush 42 causes a direct current to flow through the field winding 32 via the slip ring 41.

The rectifying device 50 is electrically connected to the armature winding 22 of the stator 20. The rectifying device 50 is a device that rectifies an alternating current generated in the armature winding 22 into a direct current and outputs the direct current. The voltage regulator 60 is for adjusting the output voltage of the rotary electric machine 1 by controlling the field current flowing through the field winding 32, and the output voltage that changes according to the electric load or the amount of power generation is substantially It has the function of keeping it constant. The pulley 70 is for transmitting the rotation of the vehicle engine to the rotor 30 of the rotary electric machine 1, and is fastened and fixed to the other axial end of the rotary shaft 80.

In the rotary electric machine 1 having such a structure, when a DC current is supplied from the power source to the field winding 32 of the rotor 30 via the brush device 40, the field winding 32 is penetrated by the energization of the current. A magnetic flux flowing through the boss portion 35, the disk portion 36, and the claw-shaped magnetic pole portion 37 is generated. This magnetic flux is, for example, the boss portion 35 of one pole core→the disc portion 36→the first claw-shaped magnetic pole portion 37-1→the stator core 21→the second claw-shaped magnetic pole portion 37-2→the disc portion 36 of the other pole core→the boss. A magnetic circuit is formed which flows in the order of the portion 35→the boss portion 35 of one pole core.

When the above magnetic flux is guided to the first claw-shaped magnetic pole portion 37-1 and the second claw-shaped magnetic pole portion 37-2, the first claw-shaped magnetic pole portion 37-1 is magnetized to the N pole and the second claw-shaped magnetic pole portion 37-1 is magnetized. The magnetic pole portion 37-2 is magnetized to the S pole. When the direct current supplied from the power supply is converted into, for example, three-phase alternating current and supplied to the armature winding 22 in the state where the claw-shaped magnetic pole portion 37 is magnetized, the rotor 30 rotates with respect to the stator 20. To do. Therefore, the rotary electric machine 1 can be made to function as an electric motor that is driven to rotate by supplying electric power to the armature winding 22.

Further, the rotor 30 of the rotary electric machine 1 is rotated by the rotation torque of the vehicle engine being transmitted to the rotary 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 to generate an AC electromotive force in the armature winding 22. The alternating electromotive force generated in the armature winding 22 is supplied to the battery after being rectified into a direct current through the rectifying device 50. Therefore, the rotary electric machine 1 can be made to function as a generator that charges the battery by the generation of electromotive force in the armature winding 22.

In the rotor 30 of the rotating electric machine 1, the permanent magnet 34 is arranged in the gap space 38 between the first claw-shaped magnetic pole portion 37-1 and the second claw-shaped magnetic pole portion 37-2 which are adjacent to each other in the rotation circumferential direction. .. A surface of the claw-shaped magnetic pole portion 37 facing the circumferential direction of rotation on the side of the clearance space 38 and a surface of the permanent magnet 34 facing the circumferential direction of rotation are substantially opposed to each other. Hereinafter, the surface of the claw-shaped magnetic pole portion 37 will be referred to as the facing surface 37a, and the surface of the permanent magnet 34 will be referred to as the facing surface 34a.

In the rotor 30, the magnetic reluctance of the claw-shaped magnetic pole portion 37 and the permanent magnet 34 in the directions opposed to each other in the circumferential direction of rotation is greater at a radially outer position closer to the stator 20 than at a radially inner position farther from the stator 20. large. The magnitude relationship of the magnetic resistance in the rotor 30 is that 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 (specifically, the circumferential distance in the rotating direction or the facing distance) is set to the radial position. It is realized by changing accordingly. Specifically, as shown in FIG. 5, the distance is longer at the radially outer position closer to the stator 20 than at the radially inner position far from the stator 20.

The facing surface 34a of the permanent magnet 34 is formed in a substantially flat shape. On the other hand, the facing surface 37a of the claw-shaped magnetic pole portion 37 is formed such that the surface thereof has irregularities that increase the distance from the facing surface 34a of the permanent magnet 34 from the radially inner side to the radially outer side. That is, the claw-shaped magnetic pole portion 37 has a recessed portion 37b that is recessed at a radially outer position of the facing surface 37a. The recess 37b is formed in such a shape that a portion having a plane substantially parallel to the facing surface 34a of the permanent magnet 34 is cut out in the circumferential direction. The portion of the facing surface of the claw-shaped magnetic pole portion 37 located inside in the radial direction may be formed in a substantially flat shape. A distance L1 between a portion of the facing surface 37a located radially outside and the facing surface 34a of the permanent magnet 34 is a distance L2 between a portion of the facing surface 37a located radially inside and the facing surface 34a of the permanent magnet 34. Large compared to.

The distance between the facing surfaces 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. It suffices that the length increases from the inner side in the radial direction to the outer side in the radial direction, and there are points that become shorter from the inner side in the radial direction to the outer side in the radial direction, such as uneven portions for stopping the flow of varnish and fixing the permanent magnet 34 or the magnet holder 39. It may be partially included. Further, it is desirable that the distance between the facing surfaces 37a and 34a in the recessed portion 37b be gradually increased from the radially inner side to the radially outer side, but the radially inner side such as the above-mentioned uneven portion for varnishing or magnet fixing. From the radial direction to the outside in the radial direction may be partially included.

As described above, the distance L1 between the portion of the facing surface 37a of the claw-shaped magnetic pole portion 37 of the rotor 30 located on the radially outer side (the recessed portion 37b) and the facing surface 34a of the permanent magnet 34 is the diameter of the facing surface 37a. If it is larger than the distance L2 between the portion located on the inner side in the direction and the facing surface 34a of the permanent magnet 34, the gap between the claw-shaped magnetic pole portion 37 and the permanent magnet 34 in the rotational circumferential direction is larger than the inner side in the radial direction. It becomes larger outside the direction. In this case, the magnetic resistance flowing in the rotational circumferential direction between the claw-shaped magnetic pole portion 37 and the permanent magnet 34 becomes larger at the radially outer position than at the radially inner position by the amount of the larger gap, so The magnetic field flowing in the circumferential direction of rotation between the magnetic pole portion 37 and the permanent magnet 34 is less likely to flow radially outside and easier to flow radially inside.

If the resistance of the magnetism flowing in the circumferential direction of rotation between the claw-shaped magnetic pole portion 37 and the permanent magnet 34 is uniform regardless of the radial position, the exciting magnetic field generated in the armature winding 22 of the stator 20 is The claw-shaped magnetic pole portion 37 (specifically, the first claw-shaped magnetic pole portion 37-1 magnetized to the N pole) from the radially inner end of the stator 20 (specifically, its tooth portion) via the air gap. The following inconvenience occurs when the flow goes to. Specifically, the magnetic field flowing through the claw-shaped magnetic pole portion 37 is then likely to concentrate on the radially outer portion near the stator 20, which is the shortest distance in the structure, of the facing surface 37a facing the permanent magnet 34. It becomes easy for the permanent magnet 34 to flow into the facing surface 34a of the permanent magnet 34 from the radially outer portion of the facing surface 37a through the gap space 38. Then, the magnetic field flows to the adjacent claw-shaped magnetic pole portion 37 (specifically, the second claw-shaped magnetic pole portion 37-2 magnetized to the S pole) through the radially outer side (front surface side) of the permanent magnet 34. And return to the stator 20 side. Therefore, in this comparative structure, the portion of the permanent magnet 34 on the outer side (front side) in the radial direction is affected by the demagnetizing field more than other portions (specifically, on the inner side in the radial direction, that is, on the back side with respect to the surface). Since it is easily received, the operating point on the demagnetization curve on the outer side in the radial direction of the permanent magnet 34 is likely to be lower than the knick point, and as shown in FIG. 6, when the operating point is lower than the knick point, the permanent magnet 34 is In particular, the portion on the outer side in the radial direction is greatly demagnetized.

On the other hand, in the structure of the rotor 30 of the present embodiment, the exciting magnetic field generated in the armature winding 22 of the stator 20 causes the air gap from the radially inner end of the stator 20 (specifically, its teeth portion). When the magnetic field flows to the claw-shaped magnetic pole portion 37 via the magnetic field, it is difficult for the magnetic field to flow on the radial outer side where the concave portion 37b exists in the facing surface 37a facing the permanent magnet 34, and on the radial inner side where the concave portion 37b does not exist. Makes it easier to flow. In this case, the magnetic field flowing 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 flowing from the facing surface 37a to the permanent magnet 34 side causes the facing surface 37a. Dispersed in the entire radial direction.

For this reason, it is possible to suppress a large demagnetizing field from acting locally on the permanent magnet 34 (specifically, radially outward near the stator 20), and the permanent magnet 34 is affected by the demagnetizing field. It can be made uniform at radial positions 34. In this case, as shown in FIG. 7, it is possible to prevent the operating point on the demagnetization curve on the radially outer side of the permanent magnet 34 from falling below the knick point. Therefore, according to the structure of the rotary electric machine 1, it is possible to prevent local demagnetization of the permanent magnet 34 and improve the demagnetization resistance performance of the permanent magnet 34.

The magnetization of the rotor 30 is performed in 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 attached to the rotary shaft 80 that constitutes the rotor 30 (step S100 shown in FIG. 8). Then, the permanent magnet 34 before magnetization is assembled to the field core 31 (step S110). The assembling of the non-magnetized permanent magnet 34 is performed for each gap space 38 between the two claw-shaped magnetic pole portions 37-1 and 37-2 of the field core 31. The permanent magnet 34 is assembled by inserting the permanent magnet 34 in the axial direction from the axial end of the field core 31 while the permanent magnet 34 is held by the magnet holder 39. A magnetizing current is applied to the armature winding 22 of the stator 20 while the rotor 30 is opposed to the stator 20 in the radial direction with an air gap or set in the magnetizing device. The permanent magnet 34 is magnetized by the magnetic field generated by the flow (step S120).

In the configuration in which the permanent magnets 34 are magnetized in the state of being incorporated in the rotor 30 as described above, the magnetizing magnetic field is similar to the above-mentioned demagnetizing field, and the recessed portion 37b of the facing surface 37a facing the permanent magnets 34 is formed. Is difficult to flow on the outer side in the radial direction, and tends to flow on the inner side in the radial direction where the recess 37b does not exist. In this case, the magnetizing magnetic field flowing to the claw-shaped magnetic pole portion 37 is guided to a portion radially inside the claw-shaped magnetic pole portion 37, and the magnetizing magnetic field flowing out from the facing surface 37a to the permanent magnet 34 side is generated. It is dispersed in the entire radial direction of the facing surface 37a. Therefore, according to the structure of the rotary electric machine 1, that is, the rotor 30, the magnetizing magnetic field received by the permanent magnet 34 can be made uniform at the radial position of the permanent magnet 34, and the magnetizing of the permanent magnet 34 is not uniform as a whole. It can be prevented.

In addition, in the rotor 30 of the rotating electric machine 1, the claw-shaped magnetic pole portion 37 has the above-described recessed portion 37b and the protruding portion 37c. The projecting portion 37c projects outward in the circumferential direction of rotation on the radially outer side of the recess 37b. The tip side of the protrusion 37c is located radially outward of the permanent magnet 34, and faces the permanent magnet 34 in the radial direction. The protruding portion 37c has a function of preventing the permanent magnet 34 from coming off to the outside in the radial direction.

As described above, the 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 capable of covering the permanent magnet 34. The magnet holder 39 extends in the axial direction (to be exact, in the oblique direction of the axial direction inclined in the circumferential direction). The magnet holder 39 has a function of restricting radial movement of the permanent magnet 34 with respect to the claw-shaped magnetic pole portion 37, and also moves the permanent magnet 34 in the circumferential direction of rotation with respect to the claw-shaped magnetic pole portion 37. Has the function of regulating The magnet holder 39 may have a function of restricting the axial movement of the permanent magnet 34 with respect to the claw-shaped magnetic pole portion 37. The magnet holder 39 has a bottom portion 39a, a side wall portion 39b, and a locking portion 39c.

The bottom portion 39a is a portion that spreads along the circumferential direction of rotation, and contacts the radially inner end surface of the permanent magnet 34 to hold the permanent magnet 34. The permanent magnet 34 is interposed between the bottom portion 39a of the magnet holder 39 and the protruding portion 37c of the claw-shaped magnetic pole portion 37, so that the permanent magnet 34 interferes with the magnet holder 39 and the claw-shaped magnetic pole portion 37 in the radial direction. As a result, the radial movement of the permanent magnet 34 is restricted.

The side wall portion 39b is a portion erected radially outward from both ends of the bottom portion 39a in the rotation circumferential direction, and contacts the rotation circumferential direction end surface of the permanent magnet 34 to hold the permanent magnet 34. The permanent magnet 34 is sandwiched between the two side wall portions 39b of the magnet holder 39, so that the permanent magnet 34 interferes with the magnet holder 39 in the rotation circumferential direction. The side wall portions 39b on both sides of the bottom portion 39a are separated from each other by the same distance as the separation distance (that is, the size of the gap space 38) between the two claw-shaped magnetic pole portions 37 adjacent to each other in the circumferential direction of rotation. Therefore, the magnet holder 39 interferes with the claw-shaped magnetic pole portion 37 in the rotation circumferential direction. As a result, the movement of the permanent magnet 34 with respect to the claw-shaped magnetic pole portion 37 in the circumferential direction of rotation is restricted.

The locking portion 39c is a flange-shaped portion that extends outward from the radial outer end of each side wall portion 39b in the rotational circumferential direction and is housed in the recess 37b of the claw-shaped magnetic pole portion 37. The outer surface of the claw-shaped magnetic pole portion 37 forming the recess 37b and the protruding portion 37c are engaged and fitted. When the locking portions 39c corresponding to the respective side wall portions 39b are housed and locked in the recesses 37b of the claw-shaped magnetic pole portions 37, the magnet holder 39 causes the outer surface and the protrusions 37c forming the recesses 37b. The position is fixed with respect to the claw-shaped magnetic pole portion 37 by a frictional force with the. As a result, 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.

In this manner, 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. Therefore, 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 and chipping due to the shock magnetic field when the permanent magnet 34 is magnetized. The movement of the magnet holder 39 and the permanent magnet 34 with respect to the claw-shaped magnetic pole portion 37 can be restricted by using the recess 37b formed in the claw-shaped magnetic pole portion 37. For this reason, the concave portion of the claw-shaped magnetic pole portion 37 necessary for accommodating a part of the magnet holder 39 and restricting the movement of the magnet holder 39, and the claw-shaped magnetic pole portion 37 for preventing local demagnetization of the permanent magnet 34. It is not necessary to provide it separately from the recess 37b formed in the above, and the function of both recesses can be shared by one recess 37b. As a result, the shapes of the rotor 30 and the claw-shaped magnetic pole portion 37 can be simplified and the molding can be facilitated.

The magnet holder 39 is made of a soft magnetic material. When the magnet holder 39 that holds the permanent magnet 34 is made of a magnetic material, the magnet holder 39, which is a magnetic body, is arranged between the permanent magnet 34 and the claw-shaped magnetic pole portion 37 over substantially the entire radial direction. It will be. Therefore, the magnetic resistance of the entire permanent magnet 34 can be reduced and the permeance thereof can be increased as compared with the case where the magnet holder 39 does not exist or the magnet holder 39 is not formed of a magnetic material. The demagnetizing field of the permanent magnet 34 can be further reduced.

Further, in the rotary electric machine 1, the rotor 30 has the permanent magnet 34 arranged between the two claw-shaped magnetic pole portions 37 that are adjacent to each other in the rotation circumferential direction. When the permanent magnet 34 is incorporated in the rotor 30, 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 increases when the centrifugal force is generated, so the strength of the rotor 30 may decrease. On the other hand, the rotor 30 has a cylindrical magnetic pole cylinder portion 33 arranged radially outside the claw-shaped magnetic pole portion 37 so as to cover the outer peripheral surface thereof. According to the magnetic pole cylinder portion 33, the plurality of claw-shaped magnetic pole portions 37 arranged in the circumferential direction of rotation are connected to each other through the magnetic pole cylinder portion 33, so that the permanent magnet 34 acts on the rotor 30 as the weight increases. Even if the centrifugal force is increased, the deformation of the claw-shaped magnetic pole portion 37 can be suppressed, and the strength reduction can be suppressed.

As is clear from what has been described above, the rotating electric machine 1 includes the annular stator 20 in which the armature winding 22 is wound around the stator core 21, and the rotor arranged to face the inside of the stator 20 in the radial direction. 30 is provided. The rotor 30 has a field core 31, a field winding 32, and a permanent magnet 34. The field core 31 has a cylindrical boss portion 35 and a plurality of claw-shaped magnetic pole portions 37 which are arranged radially outside the boss portion 35 and in which magnetic poles of different polarities are alternately formed in the rotation circumferential direction. The field winding 32 is wound around the outer periphery of the boss portion 35 and generates a magnetomotive force when energized. The permanent magnet 34 is arranged between the claw-shaped magnetic pole portions 37-1 and 37-2 adjacent to each other in the circumferential direction of rotation so that the easy axis of magnetization is oriented in the circumferential direction, and the claw-shaped magnetic pole is generated by the magnetomotive force of the field winding 32. The magnetic poles are formed so as to match the polarities that alternately appear in the portion 37. Further, the magnetic resistance of the claw-shaped magnetic pole portion 37 and the permanent magnet 34 in the directions opposed to each other in the circumferential direction of rotation is larger at the radially outer position closer to the stator 20 than at the radially inner position farther from the stator 20. Specifically, the distance between the facing surfaces of the claw-shaped magnetic pole portion 37 and the permanent magnet 34 that face each other in the circumferential direction of rotation is at a radially outer position closer to the stator 20 than at a radially inner position farther from the stator 20. Is longer.

According to this configuration, the magnetic field flowing in the rotational circumferential direction between the claw-shaped magnetic pole portion 37 and the permanent magnet 34 is hard to flow outside in the radial direction and easily flows inside in the radial direction. The magnetic field flowing to the portion 37 is guided to a portion radially inward of the claw-shaped magnetic pole portion 37, and the magnetic field flowing from the claw-shaped magnetic pole portion 37 to the permanent magnet 34 side is dispersed in the entire radial direction of the facing portion. .. Therefore, the influence of the demagnetizing field on the permanent magnet 34 can be made uniform at the radial position of the permanent magnet 34. Therefore, it is possible to prevent local demagnetization of the permanent magnet 34 and improve its demagnetization resistance performance.

In the rotating electric machine 1, the claw-shaped magnetic pole portion 37 has a recessed portion 37b that is recessed at a radially outer position of the facing surface 37a. With this configuration, the distance between the facing surfaces of the claw-shaped magnetic pole portion and the permanent magnet that face each other in the circumferential direction of rotation can be made longer at the radially outer position than at the radially inner position.

In the rotary electric machine 1, the rotor 30 has a magnet holder 39 that holds the permanent magnet 34, a part of which is housed in the recess 37 b. With this configuration, a part of the magnet holder 39 that holds the permanent magnet 34 can be housed 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. Can be fixed.

In the rotating electric machine 1, the claw-shaped magnetic pole portion 37 has a recess 37b and a protrusion 37c that projects in the circumferential direction on the outer side in the radial direction of the recess 37b, and the magnet holder 39 forms the recess 37b. It is locked to the outer surface and the protrusion 37c. With 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. Therefore, it is possible to 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.

In the rotary electric machine 1, the magnet holder 39 is made of a magnetic material. According to this structure, since the magnet holder 39, which is a magnetic body, is arranged 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. Yes, you can increase its permeance. Therefore, the demagnetizing field of the permanent magnet 34 can be further reduced.

Further, in the rotary electric machine 1, the permanent magnet 34 is a magnet that is magnetized in a state of being assembled between the claw-shaped magnetic pole portions 37 that are adjacent to each other in the circumferential direction of rotation. According to this configuration, the magnetizing magnetic field flowing in the rotational circumferential direction between the claw-shaped magnetic pole portion 37 and the permanent magnet 34 is hard to flow on the radially outer side and easily flows on the radially inner side. The magnetizing magnetic field flowing into the claw-shaped magnetic pole portion 37 is guided to a radially inner portion of the claw-shaped magnetic pole portion 37, and the magnetizing magnetic field flowing from the claw-shaped magnetic pole portion 37 to the permanent magnet 34 side is dispersed in the entire radial direction of the facing portion. To be done. Therefore, the magnetizing magnetic field received by the permanent magnet 34 can be made uniform at the radial position of the permanent magnet 34, so that the magnetizing of the permanent magnet 34 can be prevented from becoming non-uniform as a whole. ..

(Variation)
By the way, in the above-described 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 is closer to the stator 20 in the radial outside position than to the stator 20 in the radial inner position. In order to increase the length of the claw-shaped magnetic pole portion 37, a recessed portion 37b formed in a shape that is formed by cutting out a planar portion in a portion of the facing surface 37a of the claw-shaped magnetic pole portion 37 that is located on the radially outer side of the facing surface 37a that faces the permanent magnet 34. Will be provided. However, the present invention is not limited to this. The claw-shaped magnetic pole portion 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 addition, in the above-described embodiment, the claw-shaped magnetic pole portion 37 of the rotor 30 has the recess portion 37b and the protrusion portion 37c that projects in the rotation circumferential direction on the outer side in the radial direction of the recess portion, and The engaging portion 39c of the magnet holder 39 holding the permanent magnet 34 is engaged and fitted to the outer surface of the recess 37b and the protruding portion 37c. However, the present invention is not limited to this. For example, as shown in FIG. 11, the concave portion 37b of the claw-shaped magnetic pole portion 37 is a portion formed in a taper shape at a corner portion where the radially outer end of the claw-shaped magnetic pole portion 37 and the rotation circumferential direction end intersect. As the claw-shaped magnetic pole portion 37 does not have the above-mentioned protruding portion 37c, and the magnet holder 39 is formed by the inner peripheral surface of the magnetic pole cylinder portion 33 and the outer surface forming the recess 37b. It is also possible to abut against those surfaces and fit and fix them. Also in this modified structure, the magnet holder 39 is used because the magnet holder 39 is fixed in position with respect to the claw-shaped magnetic pole portion 37 by the frictional force between the outer surface forming the recess 37b and the magnetic pole tube portion 33. It is possible to restrict movement of the permanent magnet 34 with respect to the claw-shaped magnetic pole portion 37 and the magnetic pole cylinder portion 33. Therefore, it is possible to 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.

In the above modification, the locking portion 39c of the magnet holder 39 is housed in the recess 37b of the claw-shaped magnetic pole portion 37 and is locked to the outer surface of the recess 37b and the protrusion 37c. .. However, the present invention is not limited to this. While the permanent magnet 34 is sandwiched between the bottom portion 39a of the magnet holder 39 and the projection portion 37c of the claw-shaped magnetic pole portion 37 or the magnetic pole tube portion 33, the locking portion 39c of the magnet holder 39 is formed on the outer surface forming the recess portion 37b. It may be hooked on a surface facing radially outward. In order to realize this structure, the distance between the bottom portion 39a and the locking portion 39c of the magnet holder 39, that is, the height of the side wall portion 39b and the radial height of the permanent magnet 34 are defined to have a predetermined relationship. And it is sufficient.

Further, in the above-described embodiment, the recessed portion 37b is provided in the portion of the facing surface 37a of the claw-shaped magnetic pole portion 37 facing the permanent magnet 34, which is located on the radially outer side, and the facing surface of the claw-shaped magnetic pole portion 37 is provided. By increasing the distance between 37a and the facing surface 34a of the permanent magnet 34 at the radially outer position closer to the stator 20 than at the radially inner position farther from the stator 20, the claw-shaped magnetic pole portion 37 and the permanent magnet 34 are provided. With respect to the magnetic resistance in the directions opposed to each other in the circumferential direction of rotation, the magnetic resistance at the radially outer position closer to the stator 20 is made longer than at the radial inner position far from the stator 20. However, the present invention is not limited to this. It is assumed that the permanent magnet 34 has a recess formed in a shape in which a flat surface is cut out in a portion of the surface 34a facing the claw-shaped magnetic pole portion 37, which is located on the radially outer side, and the above-mentioned distance relationship And the relationship of magnetic resistance may be realized. Further, as shown in FIG. 12, the permanent magnet 34 may be formed in a tapered shape such 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 magnetic resistance of the claw-shaped magnetic pole portion 37 and the permanent magnet 34 in the directions facing each other in the circumferential direction of rotation is set to be longer at the radially outer position than at the radially inner position. 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 set longer at the radially outer position than at the radially inner position. However, the present invention is not limited to this. In order to realize the above-described magnetic resistance relationship, the magnetic permeability of the facing portions of the claw-shaped magnetic pole portion 37 and the permanent magnet 34, which face each other in the circumferential direction of rotation, is set to be larger at the radially outer position than at the radially inner position. You may make it small. Also in the configuration of this modification, the same effect as that of the above-described embodiment can be obtained.

For example, the facing surface 37a of the claw-shaped magnetic pole portion 37 and the facing surface 34a of the permanent magnet 34 are both formed in a substantially flat shape, and the distance between the facing surfaces 37a and 34a is set from the radial inside to the radial direction regardless of the radial position. The magnetic permeability of the facing portion of at least one of the claw-shaped magnetic pole portion 37 and the permanent magnet 34 is constant at the outer side in the radial direction nearer to the stator 20 than at the radially inner side far from the stator 20. One may be made smaller.

Further, for example, as shown in FIG. 13, the recess 37b of the claw-shaped magnetic pole portion 37 is formed in a tapered shape at the corner where the radially outer end of the claw-shaped magnetic pole portion 37 and the circumferential edge of the claw-shaped magnetic pole portion 37 intersect to form a claw shape. The distance between the facing surface 37a of the magnetic pole portion 37 and the facing surface 34a of the permanent magnet 34 is longer at the radially outer position than at the radially inner position, and then the claw-shaped magnetic pole portion 37 is provided in the recess 37b. It is also possible to press-fit the magnetic body 90 made of a magnetic material having a smaller magnetic permeability than that of the above, or to pour the magnetic material and perform the filling molding. The magnetic material having a magnetic permeability smaller than that of the claw-shaped magnetic pole portion 37 may be, for example, soft ferrite. Further, in this press-fitting or filling molding, after the locking portion 39c of the magnet holder 39 is housed and mounted in the recess 37b, the rod-shaped magnetic body 90 is press-fitted into the gap of the recess 37b or its magnetic material. May be poured.

Further, for example, the facing surface 37a of the claw-shaped magnetic pole portion 37 and the facing surface 34a of the permanent magnet 34 are both formed into a substantially flat shape, and the distance between the facing surfaces 37a and 34a is set from the radial inner side regardless of the radial position. The magnetic permeability of the magnet holder 39 disposed between the facing surfaces 37a and 34a is set to be constant toward the outside in the direction, and the magnetic permeability at the radial outside position closer to the stator 20 compared to the radial inside position far from the stator 20. You may make it small.

In the above embodiment, the permanent magnet 34 is magnetized after being incorporated in the rotor 30. For example, an annular stator 20 having an armature winding 22 wound around a stator core 21 and a rotor 30 arranged to face the inside of the stator 20 in the radial direction are provided, and the rotor 30 has a tubular boss. A field core 31 having a portion 35 and a plurality of claw-shaped magnetic pole portions 37 arranged radially outside the boss portion 35 and having magnetic poles of different polarities formed alternately in the circumferential direction of rotation, and the outer periphery of the boss portion 35. The permanent magnet 34, which is wound on the side, is disposed between the field winding 32 that generates a magnetomotive force by energization and the claw-shaped magnetic pole portion 37 that is adjacent in the circumferential direction of rotation so that the easy axis of magnetization is oriented in the circumferential direction. And the magnetic resistance at the radially outer position near the stator 20 in the direction in which the claw-shaped magnetic pole portion 37 and the permanent magnet 34 oppose each other in the circumferential direction of rotation is the magnetic resistance at the radially inner position far from the stator 20. A method of magnetizing a permanent magnet 34 constituting a rotating electric machine, which is larger than resistance, in which the permanent magnet 34 is incorporated into a rotor 30 and then the permanent magnet 34 is magnetized by a magnetomotive force of a field winding 32. Magnetization is performed so that magnetic poles are formed so as to match the polarities alternately appearing at 37. According to this configuration, all the permanent magnets 34 arranged in the rotation circumferential direction can be magnetized at the same time, so that the permanent magnets 34 can be easily magnetized.

However, the present invention 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 invention is not limited to the above-described embodiments and modifications, and various modifications can be made without departing from the spirit of the present invention. For example, the rotating electric machine 1 and thus the rotor 30 may be configured by combining the above-described embodiments and the modified embodiments.

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

Claims (6)

A rotating electric machine comprising an annular stator (20) in which an armature winding (22) is wound around a stator core (21), and a rotor (30) arranged to face the inside of the stator in the radial direction. 1) and
The rotor is
A field core having a tubular boss portion (35) and a plurality of claw-shaped magnetic pole portions (37) arranged radially outside the boss portion and having magnetic poles of different polarities alternately formed in the circumferential direction of rotation. (31),
A field winding (32) that is wound around the outer periphery of the boss portion and that generates a magnetomotive force when energized;
An easy axis of magnetization is arranged between the claw-shaped magnetic pole portions adjacent to each other in the circumferential direction of rotation so that the easy axis of magnetization is oriented in the circumferential direction so as to coincide with the polarity that appears alternately on the claw-shaped magnetic pole portions due to the magnetomotive force of the field winding. A permanent magnet (34) having a magnetic pole formed on
Have
The distance between the facing surfaces of the claw-shaped magnetic pole portion and the permanent magnet that face each other in the circumferential direction of rotation is longer at a radial outer position closer to the stator than at a radial inner position far from the stator,
Wherein said claw-shaped magnetic pole portions mutually rotating circumferential-direction magnetic resistance opposed to the permanent magnet, is more in Ki径 outward position before than previously Ki径 inward position rather large,
The claw-shaped magnetic pole portion has a recessed portion (37b) recessed at the radially outer position of the facing surface,
The rotating electric machine , wherein the rotor has a magnet holder (39) for holding the permanent magnet, a part of which is housed in the hollow portion . The claw-shaped magnetic pole portion includes the recess portion and a protrusion portion (37c) that protrudes in the rotation circumferential direction on the outer side in the radial direction of the recess portion,
The magnet holder is locked to the outer surface and the projecting portion forming the recess, the rotary electric machine according to claim 1, wherein. The rotor has a cylindrical magnetic pole core (33) arranged radially outside the claw-shaped magnetic pole portion so as to cover the outer peripheral surface of the claw-shaped magnetic pole portion,
The magnet holder, the is fitted and fixed in a space formed by an outer surface forming the recess portion of the inner peripheral face of the pole core and the claw-shaped magnetic pole portions, the rotary electric machine according to claim 1, wherein. The magnet holder is formed of a magnetic material, the rotating electrical machine of any one of claims 1 to 3. Permeability of the facing portions facing each other circumferential direction of rotation of the permanent magnet and the claw-shaped magnetic pole portions, is smaller in the radially outward position than that of the radially inner position, any of claims 1 to 4 A rotating electric machine according to item 1. The permanent magnet is magnetized magnet assembled state between the claw-shaped magnetic pole portion adjacent to the circumferential direction of rotation, the rotating electrical machine of any one of claims 1 to 5.

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