JP2012034483A - Axial gap motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an axial gap motor that eliminates the need for a large-scale configuration for generating and adjusting a field, allows a weak field operation by a new configuration where permanent magnets are not exposed to opposing magnetic fields, and overlaps excitation magnetic flux generated by excitation coils of the axial gap motor with field magnetic flux generated by using the permanent magnets, so as to increase magnetic flux.SOLUTION: Field permanent magnets 5b are provided in either of a first rotor 31b or a surface of a stator 2b that faces the first rotor 31b. Field coils 6b are provided in either of a second rotor 32b or a surface of the stator 2b that faces the second rotor 32b. Thus, the configuration eliminates the need for a large-scale configuration for generating and adjusting a field and allows a weak field operation by the configuration where the permanent magnets 5b are not exposed to opposing magnetic fields.

Description

  The present invention relates to an axial gap motor having a structure in which both front and back surfaces of a stator are magnetic pole surfaces and a rotor is disposed so as to face both sides of the stator. The present invention relates to a structure that generates magnetic flux.

  Conventionally, there are various types of axial gap motors in which the stator and the rotor are arranged in the direction of the motor shaft so that the magnetic pole surfaces face each other.

  The present applicant has already invented and applied for an axial gap motor having a structure in which a stator is disposed on each of both the front and back sides of a rotor (Japanese Patent Application No. 2010-058974).

  FIG. 13 shows the axial gap motor 101 of the above-mentioned application. The axial gap motor 101 is arranged in order from the output side (the front side on the left side of the paper) of the motor shaft 102, one (front side) stator 103a, the rotor 104, and the other (back side). The stator 103b is provided with a gap (gap) so that the magnetic pole faces face each other. In addition, the broken line in a figure shows the non-opposing magnetic pole of stator 103a, 103b.

  The stators 103a and 103b on both sides of the rotor 104 have a single-sided magnetic pole configuration in which the magnetic pole surface faces the rotor 104. The double-sided magnetic rotor 104 has both sides of the magnetic pole surface and is supported by the motor shaft 102 and rotated. To do.

  14A and 14B show the stators 103a and 103b. The axial gap motor 101 is a three-phase reluctance motor of A, B, and C, and the stators 103a and 103b are fan-shaped, for example, formed of a dust core having a stator magnetic pole pair 131. A stator core 132 having a shape with a part cut away is provided at intervals of 30 degrees in the circumferential direction. The stator magnetic pole pair 131 has teeth of a pair of magnetic poles 131a and 131b protruding in the direction of the rotor 104 on the outer diameter side and the inner diameter side, and the teeth are connected by a core 131c.

  The stator core 132 having the stator magnetic pole pairs 131 of the respective stators 103a and 103b is fitted with non-magnetic metal ring bodies 151 and 152 on the outer diameter side and inner diameter side in a radially arranged state. And is fixed in an annular shape in a magnetically independent state. A space (gap) between the stator cores 132 having the stator pole pairs 131 is a space for reducing the weight.

  Each of the stator magnetic pole pairs 131 of the stators 103a and 103b, for example, forms a magnetic pole pair of each phase in the order of A phase, B phase, and C phase clockwise when viewed from the front side, and each of the four magnetic pole pairs shifted by 90 degrees. A magnetic pole pair is a magnetic pole pair in which each phase is excited simultaneously.

  In each of the stators 103a and 103b, each of the stator magnetic pole pairs 131 has an extremely large number and quantity of coils of the stators 103a and 103b when a concentrated winding exciting coil is provided for each of the magnetic poles 131a and 131b. The portion of the stator core between the magnetic poles 131a and 131b is provided with an exciting coil 106 that is commonly used for exciting the magnetic poles 131a and 131b, and is formed so as to minimize the number and amount of coils of the stators 103a and 103b. In this case, for example, when each A-phase excitation coil 106 is energized, the magnetic flux of each excitation coil 106 passes through each stator magnetic pole pair 131 in the radial direction so that the magnetic poles 131a and 131b have N poles and S poles (or their poles). On the contrary, it is excited. Each exciting coil 106 is drawn out to a pair of terminals of each phase by a connecting wire 161 on the outer diameter side and inner diameter side.

  FIG. 15A shows a magnetic pole surface on the front side of the rotor 104, for example, and the rotor 104 has a fan-shaped pair of rotor magnetic poles 141 as rotor magnetic poles on both the front and back surfaces (more precisely, from the same fan shape as the stator core 131 to the center point portion). 8 rotor cores 142 are provided at intervals of 45 degrees in the circumferential direction, and the front and back are symmetrical. Each rotor magnetic pole pair 141 has a configuration in which teeth of the pair of magnetic poles 141a and 141b on the outer diameter side and the inner diameter side facing the pair of magnetic poles 131a and 131b of the stators 103a and 103b are connected by the core 141c. Similarly to 131, nonmagnetic metal ring bodies 191 and 192 on the outer diameter side and inner diameter side are fitted and fixed radially (annular).

  Each rotor magnetic pole pair 141 on the front and back sides of the rotor 104 is actually formed by integrally forming a magnetic pole pair on the front and back sides of, for example, a dust core rotor core (yoke). 142) are insulated by a gap between the cores 142 and are magnetically independent.

  FIG. 15B is a perspective view of the rotor 104 when the rotor magnetic pole pairs 141 on the front and back sides are integrally formed by a common yoke of the dust core, and each rotor core 142 of the dust core has a magnetic pole 141a on the front and back. , 141b protruding teeth are formed, and the teeth are connected by a concave core 141c.

  When the stators 103a and 103b and the rotor 104 are assembled as shown in FIG. 13, the portions of the excitation coil 106 mounted on the stator magnetic pole pairs 131 of the stators 103a and 103b that protrude in the direction of the rotor 104 The rotor core 141c between the teeth is rotatably fitted. Further, the thin portion on the outer diameter side of the rotor 104 faces the protruding thick portion on the outer diameter side of the stator 103a, 103b, and the inner diameter of the rotor 104 faces the thin portion on the inner diameter side of the stator 103a, 103b. Thick portions protruding toward the stators 103a and 103b on the side face each other.

  The axial gap motor 101 configured as described above operates by energizing each phase of the exciting coil 6 in the order of A phase, B phase, and C phase.

  In the above-mentioned existing application, an annular field coil is disposed on the stators 3a and 3b so as to overlap the respective excitation coils 6 of the stators 3a and 3b, and a DC field magnetic flux of the field coil is applied to the stator 3a. It is also described that torque is increased by increasing the amount of magnetic flux by superimposing the magnetic flux on the magnetic flux of each stator pole pair 31 of 3b in a lump.

  By the way, in this type of axial gap motor, in order to increase the motor output and torque, when the field magnetic flux is superimposed on the excitation magnetic flux generated by the excitation coil as described above, the field magnetic flux is generated using a permanent magnet. In this case, the efficiency can be improved by omitting the power supply of the field coil.

  However, when a field magnetic flux is generated using a permanent magnet, field weakening operation is required to reduce the interlaced magnetic flux of the stator coil in a high rotation range.

  In an axial gap motor having a structure in which a rotor is provided with a permanent magnet to generate a field, at least a part of the surface of the permanent magnet facing the stator is covered with a ferromagnetic material, and a reverse magnetic field from the stator is applied. It has been proposed to perform field-weakening operation (see, for example, Patent Document 1 (abstract, paragraphs [0007] to [0012], FIG. 1 to FIG. 3)).

  FIG. 16 shows the configuration of the rotor described in Patent Document 1. The rotor 200 of FIG. 16 facing the stator is attached to a motor shaft (rotating shaft) 202 through which the center of a disc-shaped rotor core 201 passes. Yes. In the circumferential direction of the rotor core 101, a plurality of permanent magnets 203 for alternately forming N magnetic poles and S magnetic poles are provided. The rotor core 201 is formed of a laminated body (laminated steel sheet) of electromagnetic steel sheets, a dust core, or the like.

  On the other hand, a stator (not shown) facing the rotor 200 is configured by arranging a plurality of stator teeth portions (saliency poles) as magnetic poles around which excitation coils are wound, at equal intervals.

  The rotor 200 rotates about the motor shaft 202 by generating a reaction force in the permanent magnet 203 against the rotating magnetic flux (excitation magnetic flux) generated in the stator by switching the excitation magnetic poles in phase order.

Here, in the rotor 200, at least a part of the surface of each permanent magnet 203 facing the stator is covered with a ferromagnetic material of a ferromagnetic material layer 204 in which electromagnetic steel plates are laminated. Reference numeral 205 denotes a non-magnetized region.

  Then, the magnetic steel sheet of the ferromagnetic layer 204 blocks a part of the magnetic flux of the permanent magnet 203 so that reluctance torque can be used, and a weak magnetic field operation is performed by applying a reverse magnetic field from the stator. The expansion of several ranges is achieved.

  Further, in the switched reluctance motor operable also as a generator, a field magnetic field forming member is provided close to the motor main body including the stator 1 and the rotor in the rotation axis direction, and the field magnetic field forming member converts the permanent magnet into the field magnet. If the field forming member is provided with a field coil as a field means, the relative position between the field forming member and the motor body is changed, the size is changed to generate a field magnetic flux. It has been proposed to generate a field magnetic flux according to the amount of field current applied (for example, Patent Document 2 (abstract, paragraphs [0005]-[0013], [0032]-[0062], FIG. 1-see FIG.

  When the field magnetic field forming member of the switched reluctance motor of Patent Document 2 uses a permanent magnet as the field means, the relative position between the field forming member and the motor body is changed, and the field flux is changed by changing the size. If this is generated, the above-mentioned field-weakening operation can be performed.

JP 2005-341696 A JP 2007-37213 A

  As described in Patent Document 1, when at least a part of the surface of the rotor permanent magnet facing the stator is covered with a ferromagnetic material and field weakening operation is performed using reluctance torque, in order to adjust the field, It is necessary to apply a magnetic field opposite to the field of the permanent magnet from the stator. At this time, the permanent magnet is exposed to the reverse magnetic field. For example, when the temperature of the permanent magnet rises, demagnetization occurs. The performance of the magnet may be impaired.

  If a field weakening operation is to be realized by providing a field magnetic field forming member as described in Patent Document 2, a large scale for applying and adjusting the field separately from the motor body that generates the torque of the switched reluctance motor A field forming member and a cam driving mechanism for changing the relative position are required, and the entire motor becomes large and heavy.

  The present invention eliminates the need for a large-scale configuration for generating and adjusting a field, and allows a field-weakening operation to be performed with a novel configuration in which a permanent magnet is not exposed to a reverse magnetic field. It is an object to increase or decrease the magnetic flux by superimposing a field magnetic flux generated using a permanent magnet on the exciting magnetic flux generated by the exciting coil.

  In order to achieve the above-described object, the axial gap motor of the present invention is arranged such that both the front and back surfaces of the stator are magnetic pole surfaces, and the rotor is opposed to the both surface sides of the stator, respectively. Are arranged in a circumferential direction, and an excitation coil for the stator magnetic pole pair is provided between a pair of salient pole structures on the outer diameter side and the inner diameter side of the stay magnetic pole pair, An axial gap motor in which a rotor magnetic pole is disposed in a circumferential direction on a side of a magnetic pole surface facing the stator of the rotor, and one of the rotor and a stator surface facing the rotor is used for a field. A permanent magnet is provided, and a field coil is provided on one of the other rotor and the stator surface facing the rotor.

  In order to further simplify the configuration, it is preferable that the permanent magnet is disposed between adjacent rotor magnetic pole pairs in the circumferential direction and shared between the adjacent rotor magnetic pole pairs (Claim 2).

  In the case of the axial gap motor according to the first aspect of the present invention, the other rotor is disposed so as to face the stator surfaces on the front and back of the stator, and the one rotor (or one stator surface opposed to the rotor) has a field. A permanent magnet for magnetism is provided, and a field coil is provided on the other rotor (or the other stator surface facing the rotor). The stator is wound across the front and back of the pair of magnetic poles in which the exciting coil is divided in the radial direction (so as to turn around both stator surfaces), and generates an exciting magnetic flux passing through the opposing rotor.

  FIG. 1 is an explanatory diagram of a magnetic path of an axial gap motor 1a of the present invention, where (a) shows a magnetic path in a low / medium rotation region where no field-weakening operation is performed, and (b) shows a field-weakening field. The high-rotation region magnetic path for operation is indicated by an arrow line, and the arrow line ml is a reluctance magnetic path of the field coil. In these drawings, reference numeral 2a denotes a stator, and a pair of radial stator magnetic poles 21a having a salient pole structure is disposed in the circumferential direction on each of the front and back stator surfaces, and the stators at the same circumferential position on both stator surfaces. An excitation coil (excitation coil) 22a is wound between the magnetic poles of the magnetic pole pair 21a. One and the other rotor 31a, 32a are disposed so as to face one stator surface of the other stator 2a, and the rotor 31a, 32a is a pair of radial magnetic pole pairs 33a, 34a in the circumferential direction of the salient pole structure. Is attached to the motor shaft 4a and rotates. Further, for example, one rotor 31a is provided with permanent magnets 5a each having S poles and N poles at the positions of the inner diameter side and outer diameter side of each rotor pole pair 33a, and the other rotor 32a is provided with each rotor. An annular field coil 6a is provided in the gap between the magnetic poles of the magnetic pole pair 34a.

In the low and middle rotation range where the field weakening operation is not performed, the field magnet 6a generates a magnetic field in a direction in which the magnetic flux is increased (a direction added to the excitation magnetic flux), so that the field magnetic flux of the permanent magnet 5a is One side of the facing stator surface is mixed with the exciting coil 22a, and the field magnetic flux of the field coil 6a is mixed with the exciting coil 22a on the other facing stator surface side (see FIG. 1A).

  In the high rotation range where the field weakening operation is performed, if the current of the field coil 6a is reduced, the magnetic flux generated by the field coil 6a can be reduced, so that the interlaced magnetic flux of the exciting coil 22a can be reduced. Furthermore, in the term rotation region, the current of the field coil 6a is set to zero and no magnetic flux is generated. In the high rotation region, a field magnet is generated in the direction in which the magnetic field is reduced by the field coil 6a (the direction subtracted from the excitation magnetic flux), so that a part of the field magnetic flux of the permanent magnet 5a on the one stator surface side is generated. Passes through the magnetic path of the rotor 31a, the stator 2a, and the rotor 32a without interlacing with the exciting coil 22a, and passes through the stator 2a without interlinking with the exciting coil 22a. Guided to the magnetic path through. Therefore, the field-weakening operation is performed without exposing the permanent magnet 5a to the reverse magnetic field (see FIG. 1B). At this time, the large field forming member and the cam driving mechanism for changing the relative position described in Patent Document 2 are not required, and the entire motor is not increased in size and weight.

  Therefore, a large-scale configuration for generating and adjusting the field is unnecessary, and the field-weakening operation can be performed by a new configuration in which the permanent magnet is not exposed to the reverse magnetic field, thereby exciting the axial gap motor 1a. The magnetic flux can be increased by superimposing the field magnetic flux generated using the permanent magnet 5a on the exciting magnetic flux generated by the coil 22a.

  In the case of the axial gap motor of the present invention according to claim 2, the permanent magnet is disposed between the adjacent rotor magnetic pole pairs in the circumferential direction and shared between the adjacent rotor magnetic pole pairs, and the number and amount of permanent magnetic poles are halved. Thus, the configuration becomes simpler, and it becomes smaller and lighter.

It is explanatory drawing of the magnetic path of the axial gap motor of this invention, (a) shows the case of not performing field-weakening operation (magnetization), and (b) shows the case of field-weakening (demagnetization) operation. . It is sectional drawing of 1st Embodiment of the axial gap motor of this invention. It is a magnetic pole surface of the rotor of the axial gap motor of FIG. 2, (a) shows the rotor by the side of a permanent magnet, (b) shows the rotor by the side of reluctance. 2 is a magnetic pole surface (stator surface) of the stator of the axial gap motor of FIG. 2, (a) shows the magnetic pole surface on the permanent magnet side, and (b) shows the magnetic pole surface on the reluctance rotor side. It is sectional drawing of 2nd Embodiment of the axial gap motor of this invention. It is a magnetic pole surface of the rotor by the side of the permanent magnet of the axial gap motor of FIG. It is a perspective view of the rotor core of the rotor of FIG. It is sectional drawing of 3rd Embodiment of the axial gap motor of this invention. 10 is a magnetic pole surface of a rotor on the permanent magnet side of the axial gap motor of FIG. 9. It is a perspective view of the rotor core of the rotor of FIG. It is sectional drawing of 4th Embodiment of the axial gap motor of this invention. It is a magnetic pole surface of the stator of the axial gap motor of FIG. It is sectional drawing of the axial gap motor of an existing application. (A), (b) is the rear view and front view which looked at the stator of one side of FIG. 15 from the left side of the paper surface. (A), (b) is the front view and perspective view which looked at the rotor of FIG. 14 from the left side of the paper surface. It is sectional drawing of an example of the conventional axial gap motor.

  Next, in order to describe the present invention in more detail, embodiments will be described in detail with reference to FIGS. In these drawings, the motor shaft and the like are omitted as appropriate.

(First embodiment)
First, a first embodiment will be described with reference to FIGS.

  FIG. 2 shows a cross section along the motor shaft 4b of the axial gap motor 1b of the present embodiment. The axial gap motor 1b includes a front side (left side of the drawing) and a rear side for attaching the rotors 31b and 32b to the motor shaft 4b. Flange shafts 71 and 72 are attached. The flange shafts 71 and 72 have a shape in which a cylindrical support portion 74 is attached to the outer periphery of a disc-shaped flange portion 73 through which the motor shaft 4b penetrates the center.

  One annular (front side) rotor 31 b is attached to the front support portion 74. On the rear side, an annular stator 2b having both surfaces formed on the magnetic pole surface and the motor shaft 2 passing through the central opening is disposed. Further, the other rear (back side) rotor 32b is attached to the rear support portion 74 behind the rear portion. In this way, the rotor 31b supported by the motor shaft 4b via the flange shaft 71, the stator 2b, and the rotor shaft 32b supported by the motor shaft 4b via the flange shaft 72 in this order from the front side in the direction of the motor shaft 4b. The magnetic pole faces are arranged to face each other. The flange shafts 71 and 72 are both made of a non-magnetic material such as stainless steel.

  The stator 2b is formed, for example, by joining a front split stator 2ba and a rear split stator 2bb, and the split stators 2ba and 2bb are each of a pair of stator magnetic poles 21b having a pair of magnetic poles 23 having a radial salient pole structure. A core (stator core) is disposed in the circumferential direction, and at least the outer diameter side and the inner diameter side of the stator magnetic pole pair 21b of the front and rear divided stators 2ba and 2bb are magnetically connected to each other. In the concave core portion between the radial magnetic poles of the stator magnetic pole pair 21b at the same circumferential position of the divided stators 2ba and 2bb, an exciting coil (stator coil) 22b of a cassette coil is provided so as to go around the stator magnetic pole pair 21b on the front and back sides. An annular field coil 6b faces the concave core portion of the split stator 2b that is mounted and faces the reluctance-side rotor 32b described later.

  The rotor 31b is a permanent magnet side rotor in which the permanent magnet 5b is provided on the side of the magnetic pole surface facing the split stator 2ba, and the rotor 32b is a reluctance in which the field coil 6b is provided on the side of the magnetic pole surface facing the split stator 2bb. Side rotor.

  FIG. 3A shows a rotor 31b on the permanent magnet side. For example, eight rotor cores formed of a dust core form a radial rotor magnetic pole pair (a pair of rotor magnetic poles of the present invention) 33b having a salient pole structure. The rotor magnetic pole pairs 33b are disposed at intervals of 45 degrees in the circumferential direction. Each rotor magnetic pole pair 33b is fixed by nonmagnetic metal ring bodies 91 and 92 on the outer diameter side and the inner diameter side, and on the surface side of the pair of magnetic poles 35 of each rotor magnetic pole pair 33b with respect to the magnetic pole 35 on the outer diameter side. A magnetic field generating permanent magnet 5b having an N pole on the magnetic pole surface side (front surface side) is affixed, and a magnetic field having the magnetic pole surface side (front surface side) as an S pole is provided for the magnetic pole 35 on the inner diameter side. A permanent magnet 5b for generation is attached. Between the rotor magnetic pole pair 33b (between adjacent cores) is a non-magnetic resin filling portion 14, and each rotor core of the rotor 31b is also magnetically independent. The area where the pair of magnetic poles 35 of the magnetic rotor pole pair 33b is bonded to the permanent magnet 5b is preferably larger than the surface area of the magnetic pole 35.

  FIG. 3B shows a reluctance-side rotor 32b. This rotor 32b is composed of, for example, eight radial magnetic pole pairs 34b in the circumferential direction formed by dust cores and arranged at intervals of 45 degrees in the circumferential direction. Each rotor magnetic pole pair 34b is fixed by nonmagnetic metal ring bodies 91 and 92 on the outer diameter side and the inner diameter side, and between the rotor magnetic pole pairs 34b (between adjacent cores) is a non-magnetic resin filling portion. 115, and each rotor core of the rotor 32b is also magnetically independent. The above-described field coil 6b is fitted and attached to the concave core portion between the magnetic poles of the rotor magnetic pole pair 33b of the rotor 32b.

  FIG. 4A shows the magnetic pole surface of the split stator 2ba on the permanent magnet side facing the rotor 31b, and FIG. 4B shows the magnetic pole surface of the split stator 2ba on the reluctance side facing the rotor 32b.

  The axial gap motor 1b is basically a three-phase reluctance motor of A, B, C similar to the axial gap motor 101 of the above-mentioned application, and each of the divided stators 2ba, 2bb is, for example, a pressure motor. Twelve (four at 90 degree intervals per phase) stator cores formed of powder magnetic cores are arranged at intervals of 30 degrees in the circumferential direction, and each stator core forms a radial stator pole pair 21b, and between the stator cores The gap (between adjacent cores) is a space or a non-magnetic resin filling portion, and each one-data core is magnetically independent.

  The radial stator magnetic pole pair 21b formed by the stator cores of the split stators 2ba and 2bb has a configuration in which a pair of magnetic poles 23 having a salient pole structure on the outer diameter side and the inner diameter side are connected by a concave yoke portion between the magnetic poles. The stator magnetic pole pairs 21b are fixed by nonmagnetic metal ring bodies 81 and 82 on the outer diameter side and the inner diameter side.

  The stator magnetic pole pairs 21b at the same position in the circumferential direction of the divided stators 2ba and 2bb are each provided with an exciting coil 22b in a concave yoke portion. Further, the field yoke 6b is opposed to the concave yoke portion of each stator magnetic pole pair 21b of each stator core of the split stator 2bb on the reluctance side so as to cover the exciting coil 22b.

  When, for example, the A-phase excitation coil 22b of the stator 2b is energized, the excitation magnetic flux of the excitation coil 22b of the A-phase stator magnetic pole pair 21b of the split stator 2ba passes through the rotor 31b in the radial direction, and the split stator 2bb. The exciting magnetic flux of the exciting coil 22b of the A-phase stator pole pair 21b passes through the rotor 32b in the radial direction. The same applies when the B-phase and C-phase exciting coils 22b are energized.

  At this time, in the low / medium rotation range where field-weakening operation is not performed, not only the permanent magnet 5b but also the field coil 6b generates a field magnetic flux in the same direction as the excitation magnetic flux, as in the magnetic path of FIG. The field magnetic flux of the permanent magnet 5b intersects with the excitation magnetic flux of the divided stator 31b, and the field magnetic flux of the field coil 6b intersects with the excitation magnetic flux of the divided stator 32b. The magnetic flux intermingled with the exciting coil 22b increases, and the motor output and torque increase. On the other hand, in the high-speed rotation region in which field-weakening operation is performed, a magnetic path similar to that shown in FIG. 1B is formed, the energizing direction of the reluctance field coil 6b is reversed, and the magnetic flux is reduced accordingly. At this time, a part of the field magnetic flux generated by the permanent magnet 5b passes through the magnetic path passing through the stator 2b in the direction of the motor shaft 4b, and passes through the rotor 32b on the reluctance side without intermingling with the exciting coil 22b. Thus, the field-weakening operation is performed without the permanent magnet 5b being exposed to the reverse magnetic flux. Note that the amount of field weakening is performed by controlling the amount of energization (field amount) of the field coil 6b.

  Regardless of whether or not the field weakening operation is performed, the rotor is based on the exciting magnetic flux based on the energization of each exciting coil 22b in the order of the A phase, the B phase, and the C phase, and the field magnetic flux intersecting with the exciting magnetic flux. The axial gap motor 1b rotates by magnetic attraction between 31b and 32b and the stator 2b.

  Therefore, in the axial gap motor 1b of the present embodiment, the field permanent magnet 5b is provided on one rotor 31b as one of the stator surfaces of one rotor 31b and the stator surface of the divided stator 2ba facing the rotor 31b. The field coil 6b is provided on the stator surface of the other rotor 32b as one of the stator surfaces of the rotor 32b and the divided stator 2bb opposite to the rotor 32b, and is linked to the excitation coil (excitation coil) 22b as described above. It is possible to perform field-weakening operation by adjusting the amount of field magnetic flux, and to form a motor configuration capable of high-efficiency operation over a wide rotational speed range. And since the permanent magnet 5b is utilized, there is also an advantage that the field loss does not occur and the efficiency is high.

  Further, a large field forming member and a cam driving mechanism for changing the relative position are unnecessary, and the axial gap motor 1b can be formed in a small size and light weight without increasing the size and weight. Further, since the axial gap motor 1b is configured by including the stator magnetic pole pair 21b and the rotor magnetic pole pairs 33b and 34b that are divided in the radial direction as the stator magnetic pole and the rotor magnetic pole, there is an advantage that the magnetic path can be formed slim.

  Next, since the permanent magnet 5b is not subject to a reverse magnetic field and is difficult to demagnetize, there is an advantage that a low grade magnet can be used as the permanent magnet 5b, and an expensive Dy (dysprosium) for securing a coercive force is provided. ), Tb (terbium) and the like, and the amount of rare earth elements added can be suppressed, and the magnet cost can be further reduced.

  The magnetic poles of the stator 2b and the rotors 31b and 32b are all formed by the stator magnetic pole pair 21b and the rotor magnetic pole pairs 33b and 34b that are divided into two in the radial direction, so that the total surface area of the magnetic poles remains the same and the cross-sectional area of the magnetic path is increased. The cores of the stator 2b and the rotors 31b and 32b can be reduced in weight.

  The core of the stator magnetic pole pair 21b of the split stator 2ba and 2bb of the stator 2b is magnetically connected between the outer diameter side and the inner diameter side of the front and back magnetic pole pair 21b, so that the magnetic flux of the permanent magnet 5b is reduced during field-weakening operation. A magnetic path penetrating the stator 2b in the axial direction can be formed.

  The excitation coil (excitation coil) 22b is wound across the pair of stator magnetic poles 21b on the front and back sides, and the excitation directions are all the same. Therefore, it is possible to excite the pair of magnetic poles 23 of the stator magnetic pole pair 21b of the front and rear divided stators 2ba and 2bb with one exciting coil 22b, and there is an advantage that the number of coils and the amount of conductor used can be reduced. Further, at the time of field-weakening operation, a part of the magnetic flux of the permanent magnet 5b can be passed through the magnetic path passing through the stator 2b in the direction of the motor shaft 4b so as not to be linked to the exciting magnetic flux.

  Next, in order to dispose the annular field coil 6b and the reluctance side rotor (salient magnetic body rotor) 32b on the side where the permanent magnet 5b is not disposed, the reluctance side magnetic poles are bundled together by the field coil 6b. Can be excited. Further, when the magnetization is increased without the field weakening operation, the linkage flux of the coil exciting coil 22b can be increased to increase the torque. Further, the demagnetization in the field weakening operation can be performed by reversing the direction of the field current and drawing the magnetic flux of the permanent magnet 5b into the reluctance rotor 2bb. At this time, the magnetic field generated by the field current is permanent. The direction is to increase the magnetic flux of the magnet, and the permanent magnet 5b is not exposed to the reverse magnetic flux.

  Next, the permanent magnet 5b is arranged on the magnetic pole surface of the rotor 2ba on the permanent magnet side, and the permanent magnet 5b is set to have the N pole on the outer diameter side and the S pole on the inner diameter side. Can be used to improve torque. In addition, during field weakening operation, instead of applying a reverse magnetic field to the permanent magnet 5b as described above, the field coil 6b draws the magnetic flux into the reluctance-side rotor 2bb to shunt the magnetic flux of the permanent magnet 5b to weaken the field. Magnetic operation can be performed.

(Second Embodiment)
A second embodiment will be described with reference to FIGS. In these drawings, the same reference numerals as those in FIGS. 2 to 4 denote the same or corresponding components.

  FIG. 5 shows a cross section along the motor shaft 4c of the axial gap motor 1c of the present embodiment. The axial gap motor 1c is different from the axial gap motor 1b in that the permanent magnet of the rotor 31b on the permanent magnet side is replaced with the axial gap. The two permanent magnets 5b of the motor 1b are changed to one permanent magnet 5c.

  FIG. 6 shows a magnetic pole surface of the rotor 31b on the permanent magnet side, and FIG. 7 is an enlarged perspective view of the permanent magnet 5b.

  As is apparent from these drawings, in the present embodiment, for example, one outer pole side is the S pole and the inner diameter side is the N pole between the pair of magnetic poles 35 of the rotor pole pair 33b of the rotor 31b on the permanent magnet side. A permanent magnet 5b is disposed. The area Sb of the surface where the pair of magnetic poles 35 and the permanent magnet 5b are joined is set to a size equal to or greater than the surface area Sa of the magnetic poles so that no loss of magnetic flux occurs.

  In the case of this embodiment, the effect similar to the effect of 1st implementation ecology is acquired, and also the following effect is acquired.

  Since the surface magnetic flux density of the permanent magnet 5b is generally lower than that of a magnetic material (such as a magnetic steel sheet or a dust core), the magnetic flux density on the magnetic pole surface can be increased by processing the surface into a polyhedral shape to increase the surface area. it can. In addition, since no permanent magnetic field is applied to the permanent magnet 5b, the permanent magnet 5b can be made thin. Therefore, there is an advantage that the amount of magnet used by the permanent magnet 5b can be reduced as compared with the case of the first embodiment.

(Third embodiment)
A third embodiment will be described with reference to FIGS. In these drawings, the same reference numerals as those in FIGS. 2 to 7 denote the same or corresponding components.

  8 shows a cross section along the motor shaft 4c of the axial gap motor 1d of the present embodiment, FIG. 9 shows the magnetic pole surface of the rotor 31b on the permanent magnet side, and FIG. 10 is a perspective view of the permanent magnet portion of the rotor magnetic pole 31b. It is.

  The axial gap motor 1d of this embodiment is different from the axial gap motors 1b and 1c in that the permanent magnets 5b and 5c are not provided for each rotor magnetic pole pair 33b of the rotor 31b on the permanent magnet side, but a magnetic body on the outer diameter side. The permanent magnet 37 sandwiched between the magnetic body 36b on the inner diameter side 36a and the rotor magnetic pole pair 33b is arranged between the rotor magnetic pole pairs 33b adjacent to each other in the circumferential direction.

  In other words, the adjacent rotor cores are connected between the rotor magnetic pole pairs 33 of the rotor 31b on the permanent magnet side, the common permanent magnet 37 sandwiched between the magnetic bodies 36a and 36b is disposed, and the rotor magnetic pole pairs 33b adjacent in the circumferential direction are made permanent. The magnet 37 is shared.

  In this case, half of the rotor magnetic pole pair 33b of the switched reluctance motor 1d contributes to torque generation at each time point, and the other half is the next half, like the rotor magnetic pole pair of the previously described switched reluctance motor 101 and the like. Since it is in a standby state in preparation for being excited and generating torque, the amount of magnet use can be further reduced by sharing the permanent magnet 37 between the adjacent rotor magnetic pole pairs 33b.

(Fourth embodiment)
A fourth embodiment will be described with reference to FIGS. 11 and 12. In these drawings, the same reference numerals as those in FIGS. 2 to 10 denote the same or corresponding parts.

  FIG. 11 shows a cross section along the motor shaft 4c of the axial gap motor 1e of the present embodiment, and FIG. 12 shows the magnetic pole surface of the split stator 2ba on the permanent magnet side.

  The axial gap motor 1e of this embodiment is different from the axial gap motors 1b to 1d in that a permanent magnet and a field coil are provided in the stator 2b.

  That is, the rotor 31b is not provided with the permanent magnets 5b, 5c, and 37. The rotor 32b is not provided with the field coil 6b. Instead, on the magnetic pole surface (stator surface) facing the rotor 31b of the split stator 2ba, the S pole is on the surface side on the outer diameter side and the N pole is on the surface side on the inner diameter side. A permanent magnet 38 is attached in the direction. In order to avoid increasing the size of the motor, the thickness of the split stator 2ba in the motor axial direction is reduced by the provision of the permanent magnet 38. The field coil 6b is mounted so as to overlap the exciting coil 22b of the split stator 22b.

  In this case, the same effects as those described in the first embodiment can be obtained, and the permanent magnet 38 is provided on one of the magnetic pole faces of the both faces of the stator 2b, and the other of the both faces of the stator 2b is obtained. In the case where the permanent magnets 5b, 5c, and 37 are provided on the rotor 31b, the magnet is formed in consideration of the centrifugal force and the magnetic attractive force caused by the rotation of the rotor 31b. Although it is necessary to determine a structure for holding 5b, 5c, and 37, since the stator 2b does not rotate, no consideration is given to centrifugal force, and there is an advantage that the holding structure of the permanent magnet 38 is simplified.

  The present invention is not limited to the above-described embodiments, and various modifications other than those described above can be made without departing from the spirit thereof, for example, the stator magnetic pole pair 21b of the stator 2b. The number and shape of the rotor magnetic pole pairs 33a and 33b of the rotors 31b and 32b are not limited to those of the embodiments.

  The present invention can be applied to an axial gap motor for various uses such as a drive motor for an electric vehicle.

1a to 1e Axial gap motor 2a, 2b Stator 5a, 5b, 37, 38 Permanent magnet 6a, 6b Field coil 21a, 21b Stator magnetic pole pair 22a, 22b Excitation coil 31a, 31b, 32a, 32b Rotor 33a, 33b Rotor magnetic pole pair

Claims (2)

Both the front and back surfaces of the stator are magnetic pole surfaces, and the rotor is disposed so as to face both surface sides of the stator, and a pair of radial stator magnetic poles is disposed in the circumferential direction on each of both surface sides of the stator, An excitation coil of the stator magnetic pole pair is provided between the pair of salient pole structures on the outer diameter side and the inner diameter side of the stay magnetic pole pair, and the rotor magnetic pole is disposed on the magnetic pole surface side of the rotor facing the stator. An axial gap motor arranged in a direction,
A permanent magnet for field is provided on one of the rotor and the stator surface facing the rotor, and a field coil is provided on either the other rotor or the stator surface facing the rotor. A characteristic axial gap motor. The axial gap motor according to claim 1,
The axial gap motor according to claim 1, wherein the permanent magnet is disposed between adjacent rotor magnetic pole pairs in the circumferential direction and shared between the adjacent rotor magnetic pole pairs.

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