JP2011172302A - Axial gap motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an axial gap motor with a stator and a rotor formed by dust cores that is compact and light, can be manufactured easily, and produces a larger motor output. <P>SOLUTION: The stator 4 includes each stator core 5 of the dust core arranged circumferentially with a gap in a magnetically independent state, a magnetic pole 7 at an outside-diameter side is formed by each radial outside-diameter side portion on the front and rear of each stator core 5, and a magnetic pole 8 at an inside-diameter side is formed by a radial inside-diameter side portion. Further, a cassette coil 10 is attached to a yoke unit 9 between the magnetic poles 7, 8 of each stator core 5, and a pair of magnetic poles 11 on the front and rear of each stator core 5 is excited collectively, thus providing the new axial gap motor 1a that is compact and light, can be manufactured easily, and produces a larger motor output. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an axial gap motor in which a rotor is disposed on both sides of a front and back of a stator. More specifically, the present invention provides a new coil structure of a stator and a new magnetic pole structure of a rotor, and is small, lightweight, inexpensive, and easy to manufacture. A simple configuration.

  Conventionally, in an axial gap motor, a plurality of magnetic pole pairs formed by an outer diameter side magnetic pole and an inner diameter side magnetic pole are arranged in the circumferential direction on both the front and back surfaces of the stator, and the rotor is opposed to both the front and back surfaces of the stator. (See, for example, Patent Document 1 (paragraphs [0010]-[0015], [0029]-[0032], FIG. 1, FIG. 5, etc.)).

  FIG. 14 shows this type of axial gap motor 200 described in FIG. 1 of Patent Document 1, wherein (a) is a plan view of the magnetic pole surface of the rotor 212a viewed from the stator 211, and (b) is B in (a). It is sectional drawing of the axial gap motor 200 cut | disconnected along the -B line. The axial gap motor 200 includes a stator 211 and a pair of rotors 212a and 212b arranged with a gap (gap) between both surfaces of the stator 211, and the rotors 212a and 212b are supported by a motor shaft 213.

  In the stator 211, a plurality of outer-diameter cores (stator cores) 215 around which coils (excitation coils) 214 of respective phases are wound are arranged at substantially equal intervals in the circumferential direction, and the coils 214 are disposed inside the outer-diameter cores 215. A wound inner diameter side core (stator core) 216 is disposed. That is, in the stator 211, the outer diameter side core 215 and the inner diameter side core 216, in which the coil 214 is wound, are arranged concentrically in close proximity to the magnetic pole positions of each phase at substantially equal intervals in the circumferential direction. The coils 214 of the cores 215 and 216 at the magnetic pole positions of the respective phases are different in electrical angle of energization by 180 degrees, and are excited, for example, as U phase + U (N pole) and -U (S pole), respectively. Form.

  The rotors 212a and 212b include yokes 217a and 217b and a plurality of outer permanent magnets 218a and inner permanent magnets 218b that form magnetic poles, respectively, and are divided into approximately four equal parts by a partition 219 made of a nonmagnetic member. It has four compartments that are magnetically isolated. The permanent magnets 218a and 218b facing the stator 211 are arranged corresponding to the cores 215 and 216 of the stator 211 and have different polarities in the circumferential direction and the radial direction.

  By sequentially energizing the coils 214 of each phase, for example, the magnetic path r in FIG. 14B and the magnetic path r2 in FIG. 14A are formed, and the rotors 212a and 212b rotate. At this time, the magnetic path r2 passing through the end surface orthogonal to the motor shaft 213 is shortened, and the motor loss is reduced.

  15 shows another example of the axial gap motor 250 described in FIG. 5 of Patent Document 1, wherein (a) is a plan view of the rotor 212a viewed from the stator 246 side, and (b) is a BB of (a). It is sectional drawing which follows a line.

  As shown in FIG. 15, in the axial gap motor 250, each magnetic pole pair in the circumferential direction of the stator 246 is formed by a single core 247 in which an exciting coil 214 is wound vertically. Other configurations and operations are the same as those of the axial gap motor 200 of FIG.

  A plurality of cores 247 (four in this example) are arranged at substantially equal intervals in the circumferential direction, and a coil 214 is vertically wound along the direction of the motor shaft 213 at the central portion in the radial direction of each core 247. A groove 247a is formed. A coil 214 is wound around the groove 247a in the vertical direction (axial direction). Further, the end 247b of each core 247 other than the groove 247a faces the outer diameter side permanent magnet 218a and the inner diameter side permanent magnet 218b of the rotors 212a and 212b.

  In each core 247 of the stator 246, the axial gap motor 250 moves from the inner diameter side permanent magnet 218b of the rotor 212b to the outer diameter side permanent magnet 218a of the rotor 212a through the core 247 and through the yoke 217b. From the magnetic path r toward the side permanent magnet 218b and the inner diameter side permanent magnet 218b of the rotor 212a through the core 247 to the outer diameter side permanent magnet 218a of the rotor 212a, through the yoke 217a, the inner diameter side permanent of the rotor 212a. A magnetic path r toward the magnet 218b is formed and rotates.

JP 2007-236130 A

  In the case of the axial gap motor 200 having the configuration shown in FIG. 1 of Patent Document 1 shown in FIG. 14, coils for exciting the magnetic poles on both the front and back sides of the magnetic pole portions of the cores 215 and 216 on the outer diameter side and inner diameter side of the stator 211. Since 214 is wound, based on the thickness of these coils 214 and the like, the outer diameter side, the inner diameter side of each magnetic pole and the magnetic pole area between the magnetic poles are reduced accordingly, and the motor output is reduced. Moreover, since it is necessary to individually wind the coil 214 around the magnetic pole portions of the cores 215 and 216 on the outer diameter side and inner diameter side of the stator 211, labor is required and the manufacturing cost increases. In addition, the coil 214 is bulky and has a large coil mass, and there is a problem that the physique and mass of the axial gap motor 200 are increased.

  Further, in the case of the axial gap motor 250 having the configuration shown in FIG. 5 of Patent Document 1 shown in FIG. 15, the exciting coil 214 of the stator 246 is wound at a position retracted from the magnetic pole surface of the stator 246. The stator 246 extends in the motor axial direction and protrudes. Therefore, the volume and mass of the stator 24 are increased. Moreover, the coil 214 must be wound around each core 247 of the stator 246. Specifically, each core 247 needs to be attached to the winding machine spindle and rotated, and the coil 214 needs to be wound around each core 247. Therefore, it takes time and manufacturing costs are increased. Further, the axial gap motor 250 has a complicated magnetic flux direction as in the case of a general axial gap motor. Therefore, each core 247 is preferably formed of a dust core in which the direction of passing the magnetic flux is not limited. Is weak in mechanical strength and easily broken during the work process of attaching to the winding machine spindle. Therefore, there is a problem that the axial gap motor 250 cannot be easily manufactured.

  In the axial gap motors 200 and 250, the rotors 212a and 212b using heavy permanent magnets as the magnetic poles must have a mechanical structure that can withstand centrifugal force. Is not shown.

  In this type of axial gap motor in which the rotors are arranged on both the front and back sides of the stator, it is desired to obtain a larger motor output with a configuration that is as small and light as possible and easy to manufacture. .

  An object of the present invention is to make an axial gap motor formed using a dust core small, light and easy to manufacture, and to obtain a larger motor output.

  In order to achieve the above object, the axial gap motor of the present invention has a plurality of magnetic pole pairs formed by an outer diameter side magnetic pole and an inner diameter side magnetic pole arranged in the circumferential direction on both front and back surfaces in the motor axial direction. An axial gap motor including a stator and a rotor disposed opposite to both the front and back surfaces of the stator, wherein the stator is provided with a plurality of wedge-shaped stator cores formed of dust cores with gaps therebetween. It is formed by being arranged in the circumferential direction in a magnetically independent state, the radially outer diameter side portions of the front and back surfaces of each stator core form the outer diameter side magnetic pole, and both front and back surfaces of each stator core Each radially inner diameter portion forms the inner diameter side magnetic pole, and the pair of magnetic poles on both the front and back sides are formed on the yoke portion between the outer diameter side magnetic pole and the inner diameter side magnetic pole of each stator core. Cassette coil for exciting collectively is characterized in that it is mounted (claim 1).

  The axial gap motor of the present invention is characterized in that each stator core is formed such that the outer diameter side magnetic pole is longer in the motor axial direction than the inner diameter side magnetic pole.

  The axial gap motor of the present invention is characterized in that each stator core is formed by joining one single-sided core and the other single-sided core back to back with an adjustment plate for the magnetic pole interval interposed therebetween (claims). Item 3).

  The axial gap motor of the present invention is characterized in that annular field coils are arranged on both the front and back surfaces of the stator (claim 4).

  Further, in the axial gap motor of the present invention, each pair of magnetic poles on both the front and back surfaces of each stator forms a pair of magnetic poles in each drive phase in the circumferential direction, and the outer diameter side magnetic pole and the inner diameter side magnetic pole The polarity is reversed for each pair of magnetic pole pairs of the number of phases of the drive phase sequentially arranged in the circumferential direction, and a plurality of annular field coils for applying a magnetic field to each of the magnetic pole pairs on both sides of the stator The double-sided field coils are arranged in the stator so as to cross each pole pair of the group of magnetic pole pairs and to be reversed from each other to reverse from the front surface to the back surface of the stator. (Claim 5).

  Further, the axial gap motor of the present invention is a wedge-shaped outer diameter of a dust core in which the rotor disposed opposite to both the front and back surfaces of the stator is disposed in the circumferential direction to form a magnetic pole on the outer diameter side. And a wedge-shaped inner rotor core of a dust core that is disposed in the circumferential direction to form a magnetic pole on the inner diameter side is individually held by fitting a non-magnetic outer ring on each outer peripheral side. The rotor core is superposed in the motor axial direction, and a common ring is fitted on the inner peripheral side of the two rotor cores to be assembled (Claim 6).

  In the case of the axial gap motor of the present invention according to claim 1, in this type of axial gap motor in which the rotor is disposed on both the front and back surfaces of the stator, the stator is disposed in the circumferential direction in a magnetically independent state with a gap. Each of the stator cores of the powdered magnetic core is provided. Further, in each stator core, the radially outer diameter side portions on both the front and back surfaces form an outer diameter side magnetic pole, and the radial inner diameter side portion forms an inner diameter side magnetic pole. Each stator core is energized with a pair of magnetic poles on both the front and back surfaces by a cassette coil mounted on the yoke portion between the outer diameter side magnetic pole and the inner diameter side magnetic pole of each stator core.

  In this case, the coils need not be concentratedly wound for each magnetic pole or each magnetic pole pair on both the front and back surfaces of each stator core, and the number of coils and the coil mass of the stator are reduced. In addition, one cassette coil is attached to each stator core, and as described above, each stator core is attached to the winding machine spindle and rotated, and the coils need to be wound around the magnetic poles on both sides of each stator core 247. There is no problem, and the manufacturing cost is low. Furthermore, there is almost no possibility that the dust core having a low mechanical strength is broken during the operation, and the axial gap motor can be easily manufactured. In addition, since each magnetic pole pair of the stator is formed by the magnetic pole on the radially outer diameter side and the magnetic pole on the inner diameter side of each stator core, the magnetic pole pair of each stator pair is compared with the case where the magnetic poles are not divided in the radial direction. The amount of magnetic flux in the yoke portion between the magnetic poles is halved, the yoke magnetic path cross-sectional area of the stator and the rotor is reduced, and the stator becomes smaller and lighter.

  Therefore, the outer diameter sides of both the front and back surfaces of each stator core of the dust core disposed in the circumferential direction in a magnetically independent manner, the magnetic pole pairs on both sides of the stator formed using the dust core. An axial gap motor is formed by exciting a pair of magnetic poles on the front and back surfaces of each stator core together with one cassette coil mounted on the yoke portion of each stator core. Therefore, it is possible to provide a novel excitation structure of a stator formed by using a dust core, and to provide an unprecedented axial gap motor that is small and lightweight, can be easily manufactured, and can obtain a larger motor output.

  In the case of the axial gap motor of the present invention according to claim 2, each stator core has a magnetic pole on the outer diameter side protruding longer in the motor axis direction than the magnetic pole on the inner diameter side. In other words, the inner diameter side of each stator core is thinner than the outer diameter side, and the cassette coil can be easily mounted by being inserted into each stator core from the inner diameter side. Also, the rotor facing both the front and back surfaces of the stator, contrary to the stator, has a thinner outer peripheral side than the inner peripheral side where the action of centrifugal force is greater, so the centrifugal force applied to the outer periphery of the rotor core is smaller and faster and faster. Rotation is possible.

  In the case of the axial gap motor of the present invention according to claim 3, each stator core includes one single-sided core and the other single-sided core in consideration of the relatively large dimensional error of the core formed of the dust core. It is formed by joining back to back with an adjustment plate for the magnetic pole interval. At this time, an appropriate thickness and inclination as a magnetic pole spacing adjustment plate so as to eliminate the variation due to the dimensional error of the magnetic pole surfaces on both the front and back sides of each stator core arranged in the circumferential direction and to maintain high accuracy flatness. The wedge-shaped plate can be selected and the magnetic pole spacing in the motor axial direction between the stator and the rotor can be adjusted, so that the magnetic pole surfaces on both sides of the stator can be made flat with high accuracy.

  In the case of the axial gap motor of the present invention according to claim 4, it is possible to increase the torque by increasing the magnetic fluxes on both the front and back sides of the stator by the annular field coil that is easy to manufacture, thereby improving the motor output.

  In the case of the axial gap motor of the present invention according to claim 5, each magnetic pole pair on both the front and back surfaces of each stator is, for example, U, V, W, U in the circumferential direction in the case of U, V, W three-phase driving. , VW are formed in the order of VW, and the polarities of the magnetic poles on the outer diameter side and the inner diameter side of these magnetic pole pairs are reversed for each set of magnetic pole pairs of U, V, and W. Further, in accordance with this, a plurality of annular field coils intersect with each other of a pair of magnetic pole pairs of U, V, and W so that they are reversed from each other and switched from the front surface to the back surface, and vice versa. Since the magnetic field coils are provided on the front and back surfaces of the stator, the field magnets for increasing the excitation of the magnetic poles are applied to the magnetic poles on the front and back surfaces of the stator, thereby increasing the torque and improving the motor output. In addition, since the polarity direction of the magnetic pole pair is reversed in units of a pair of magnetic pole pairs of U, V, and W, there are few places (number of times) in which both field coils cross and reciprocate the front and back, and the field coil Increase in mass can be prevented. The reason why the polarity direction of the magnetic pole pair is reversed in units of a pair of magnetic pole pairs of U, V, and W is to simplify the connection of the cassette coils by the jumper wires.

  In the case of the axial gap motor of the present invention according to claim 6, the rotor of the dust core facing the stator is divided into an outer diameter side rotor core and an inner diameter side rotor core, and the outer peripheral side of these rotor cores is the core of the rotor In order to make the two magnetically independent, each is individually held in an annular shape by a non-magnetic outer ring, and both rotor cores are overlapped in the motor shaft direction and held on the inner ring side by a common ring.

  When a rotor having a magnetic pole portion and a yoke portion having different lengths (heights) in the motor axial direction by compressing the powder magnetic core is integrally formed, the magnetic pole on the inner diameter side, which is particularly high, is formed during compression molding. The punch that receives lateral force hits the side of the mold and the mold is easily damaged, and the compression density of the molded core varies, but the outer and inner rotor cores are formed separately. When the magnetic poles on the inner diameter side are formed repeatedly, the mold can be formed less easily damaged, the compression density becomes uniform, and the rotor receiving the centrifugal force can be accurately formed to improve the motor performance. In addition, if a metal or the like is used for the common ring on the inner peripheral side, the common ring can be easily fitted by press fitting or the like, so that both rotor cores can be integrated and held.

It is sectional drawing of the axial gap motor of the 1st Embodiment of this invention. (A), (b) is a front view by the side of the magnetic pole surface of the stator of FIG. 1, and a rotor. FIG. 2 is an enlarged front view of the stator of FIG. 1 on the magnetic pole surface side. (A), (b) is a perspective view of the stator core of the stator of FIG. 3, and its formation explanatory drawing. It is a front view by the side of the magnetic pole surface of the stator of the 2nd Embodiment of this invention. It is explanatory drawing of the field coil of the stator of FIG. It is sectional drawing of the axial gap motor of the 3rd Embodiment of this invention. (A), (b) is a front view by the side of the magnetic pole surface of the stator of FIG. 7, and a rotor. FIG. 8 is an enlarged front view of the stator of FIG. 7 on the magnetic pole surface side. It is explanatory drawing of the field coil of the stator of FIG. (A), (b) is the perspective view of the rotor of the 4th Embodiment of this invention, and explanatory drawing of the magnetic flux. It is a disassembled perspective view explaining the assembly | attachment of the rotor of Fig.11 (a). FIG. 12 is a perspective view of a part of the rotor of FIG. (A), (b) is a top view by the side of the magnetic pole surface of the rotor of a conventional example, and sectional drawing of the whole motor cut | disconnected by the BB line. (A), (b) is the top view by the side of the magnetic pole surface of the rotor of the other conventional example, and sectional drawing of the whole motor cut | disconnected by the BB line.

  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)
A first embodiment will be described with reference to FIGS.

  FIG. 1 shows an axial gap motor 1a according to this embodiment. The axial gap motor 1a is provided with a certain gap (gap) between the rotor 3a, the stator 4, and the rotor 3b in order from the output side (left side of the paper) of the motor shaft 2. The magnetic pole faces are arranged so as to face each other. The rotors 3a and 3b are supported by the motor shaft 2 and rotate. The stator 4 is fixed with a gap between the stator 4 and the motor shaft 2.

  FIG. 2A shows the stator 4. The stator 4 has a circular shape in plan view, and has a wedge-shaped plural (in this embodiment, U, V, W, three-phase, 12-pole configuration) formed of dust cores. Since the number of magnetic pole pairs to be described later per drive phase is an even number, 12 stator cores 5 are formed in the circumferential direction in a magnetically independent state with a gap.

  Each stator core 5 is annularly held by a nonmagnetic outer holder 61 and an inner holder 62. The gaps between the stator cores 5 are spaces for reducing the weight in the case of the present embodiment, but may be filled with an appropriate non-magnetic resin or the like when configured to be more robust.

  Each stator core 5 will be further described. Each stator core 5 has a radially outer diameter side portion projecting in the motor axial direction (hereinafter referred to as the axial direction) on both the front and back surfaces to form a magnetic pole 7 having an outer diameter side. The inner diameter side portion of the direction forms the inner diameter side magnetic pole 8. Then, by energization excitation of the cassette coil 10 described later, one of the magnetic poles 7 and 8 is excited to the N pole and the other to the S pole to form the magnetic pole pair 11.

  By the way, the concave portion between the magnetic poles 7 and 8 is a yoke portion 9 that connects the magnetic poles 7 and 8 in the radial direction, and a concentrated winding cassette that excites the magnetic pole pairs 11 on both surfaces of each stator core 5 collectively to the yoke portion 9. A coil 10 is attached.

  In this case, (1) since the magnetic pole pairs 11 of the magnetic poles 7 and 8 on both the front and back surfaces of the stator core 5 are excited collectively by the cassette coil 10, the number and mass of the exciting coils are reduced. (2) The magnetic poles 7 and 8 of the magnetic pole pair 11 are divided and arranged on the outer diameter side and the inner diameter side of one stator core 5 so that each of the magnetic poles of the magnetic pole pair is formed by one stator core. The magnetic flux passing through the yoke portions of the rotors 3a and 3b and the stator 4 is halved as compared with the case of an axial gap motor. Therefore, the yoke portion 9 of the stator core 5 and the yoke portion of the rotor core, which will be described later, of the rotors 3a and 3b can be thinned, and the stator core 5 and the rotor core are lightened. (3) Since the stator core 5 is inserted inside the cassette coil 10 and the cassette coil 10 is attached to the stator core 5, assembly is easy. Further, in each stator core 5, the outer diameter side magnetic pole 7 is longer in the axial direction than the inner diameter side magnetic pole 8 and protrudes in the direction of the stators 3 a and 3 b, so that the magnetic pole pair 11 has an outer diameter side in the axial direction more than the inner diameter side. It is short (thin). Therefore, the cassette coil 10 can be easily inserted by being inserted into each stator core 5 from the inner peripheral side, and the assembly is further simplified. Further, the cassette coil 10 is formed separately from the stator core 5 in the manner of manufacturing an air-core coil using a jig, and is then attached to the stator core 5. In this case, it is not necessary to attach the stator core 5 to the winding machine spindle and wind the coil, and the dust core of the stator core 5 is not broken during operation. (4) Since each cassette coil 10 protrudes in the axial direction from the magnetic pole surface of each stator core 5, each stator core 5 becomes lighter than the case where the magnetic pole surface is configured to protrude in the motor axial direction from the cassette coil 10. . (5) Since each cassette coil 10 protrudes in the axial direction from the magnetic pole face of each stator core 5, there is an advantage that the height of the magnetic pole face of the stator 4 can be reduced and the mold compression molding of the dust core becomes easy. . If there are irregularities with large differences in the height of the powder magnetic core, the punch is subject to lateral force during compression molding in the mold, and the mold tends to be damaged, and the density of the molded product varies from one compression site to another. Although it becomes easy, since the height of the magnetic pole surface of the stator 4 can be made low, each stator core 5 can be manufactured with a good yield by compressing the dust core.

  The stator core 5 and the cassette coil 10 will be described more specifically.

  FIG. 3 shows the magnetic pole surface of the stator 4 in an enlarged manner. For example, when the stator core 5 surrounded by a broken line in the figure is extracted and shown, FIG.

  FIG. 4A shows the stator core 5 with the cassette coil 10 mounted thereon, and the stator core 5 may be formed of a single core piece, but is generally a core formed by compressing a dust core. In this embodiment, one (front side) single-sided core 51 and the other (back side) single-sided core 52 are joined back to back with the magnetic pole spacing adjustment plate 12 in between. Formed. As for the single-sided cores 51 and 52, the surface side is the uneven | corrugated shape of the magnetic poles 7 and 8 and the yoke part 9, respectively, and a back side (bonding surface side) is a flush plane.

  FIG. 4B shows an example of the assembly procedure of the stator core 5. First, the single-sided cores 51 and 52 are matched back to back in the order of the numbers “1”, “2”, and “3” circled. Next, back-to-back single-sided cores 51 and 52 are fitted into the cassette coil 10 formed in a rectangular shape with a specified inner diameter from the inner peripheral side, and the cassette coil 10 is mounted on the yoke portion 9. Further, between the mating surfaces of the single-sided cores 51 and 52, an appropriate thickness selected so that (thickness of the single-sided cores 51 and 52) + (thickness of the adjusting plate 12) is within a predetermined range that matches the prescribed inner diameter dimension. The thickness adjusting plate 12 is sandwiched, and the stator core 5 is assembled in a shape in which the adjusting plate 12 is sandwiched between the single-sided cores 51 and 52. Thereby, (6) the flatness of the magnetic pole surface of the stator 4 in which each stator core 5 is disposed can be ensured, and variations in motor characteristics of the axial gap motor 1 can be reduced. (7) The cassette coil 10 is held by the yoke portion 9 between the magnetic poles 7 and 8 protruding in the axial direction and does not fall off.

  As shown in the broken line U-phase wiring path in FIG. 2A, for example, the cassette coils 10 mounted on the stator cores 5 are connected in series by the connecting wires 13 and the lead wires 14 to form a coil group. Power is supplied from a pair of terminals 15u, 15v, 15w of each phase connected to the lead wire 14 of each phase. As shown in FIG. 1, each stator core 5 has a shape in which the central portion in the axial direction is cut out and recessed in both the outer peripheral portion and the inner peripheral portion, and the crossover wire 13 and the lead wire 14 pass through the cutout portion. In this case, since (8) each cassette coil 10 of the coil group is connected by the crossover wire 13, for example, the number of coil connection points is larger than the case where both ends of each cassette coil 10 are drawn and wired to the positions of the terminals 15u to 15w. There are few, and manufacture becomes easy. (9) As indicated by broken line arrows in FIG. 1, the magnetic path of the magnetic flux is formed between the stator 4 and the rotors 3a and 3b facing each other on the front and back sides. The portion in the vicinity of the position of the adjustment plate 12 is a portion where the magnetic flux density is low. And since the said notch part is formed in the location where this magnetic flux density is low, there also exists an advantage which can reduce the weight of the stator core 5 without affecting magnetic flux. (10) By accommodating the crossover wire 13 in the core notch, an increase in the size of the stator 4 due to wiring can be prevented.

  Finally, the rotors 3a and 3b will be described. The rotors 3a and 3b have the same configuration.

  FIG. 2B shows the rotor 3a, and the rotors 3a and 3b will be described with reference to the rotor 3a.

  The rotors 3a and 3b have, for example, an 8-pole configuration, and eight wedge-shaped rotor cores 17 formed of dust cores are provided on a non-magnetic disk-like rotor cover 16 that is supported by the motor shaft 2, respectively. It is formed by being provided in the circumferential direction in a magnetically independent state with a gap. In this embodiment, the gap between the rotor cores 17 is a space for reducing the weight. However, in the case of a more robust structure, the rotor cores 17 are connected by a dust core or a laminated steel sheet yoke. Also good.

  The rotor cores 17 will be further described. In each rotor core 17, the radially outer diameter side portion of the magnetic pole surface facing the stator 4 forms an outer diameter side magnetic pole 18, and the radially inner diameter side portion is an inner diameter side magnetic pole 19. Form. The magnetic poles 18 and 19 of each rotor core 17 form a magnetic pole pair 20. Further, in each rotor core 17, the concave portion between the magnetic poles 18 and 19 and the left and right edge portions form yoke portions 21 a, 21 b and 21 c. The yoke portion 21a connects the magnetic poles 18 and 19, and when assembled to the motor 1a, each cassette coil 10 protruding in the axial direction from the magnetic pole surface of each magnetic pole pair 11 of the stator 4 rotates in the concave portion of the yoke portion 21a. It is designed to fit freely. The yoke portions 21b and 21c increase the yoke area of the rotors 3a and 3b. Of the magnetic pole pairs 11 of each stator core 5, the outer diameter side magnetic pole 7 is longer in the axial direction than the inner diameter side magnetic pole 8. 18 is shorter in the axial direction than the magnetic pole 19 on the inner diameter side.

  (11) Since the magnetic pole 18 on the outer diameter side of the magnetic pole pair 20 of each rotor core 17 is shorter in the axial direction than the magnetic pole 19 on the inner diameter side, the following advantages are obtained. That is, the magnetic pole 18 on the outer diameter side of each rotor core 17 and the yoke portion 20a and the magnetic pole 19 on the inner diameter side thereof differ in mass and mass position, and the magnitude of centrifugal force during rotation differs. On the other hand, since the Young's modulus of the dust core is relatively small, displacement due to strain occurs relatively easily when subjected to centrifugal force. Then, the displacement of the rotor core 17 due to the centrifugal force increases toward the outer diameter side, the tensile stress increases, and the core breakage of the rotors 3a and 3b is likely to occur. However, the axial gap motor 1a is strong against centrifugal force because the portion of the magnetic pole 18 on the outer diameter side on which the centrifugal force acts is short and light in the axial direction. (12) Since the portion of each cassette coil 10 protruding in the axial direction is rotatably fitted into a yoke portion (concave portion) 21a between the magnetic poles 18 and 19 of each rotor core 17, the physique of the axial gap motor 1a accordingly. And mass is reduced. The height of the magnetic pole surface of each rotor core 17 (the height in the axial direction) may be a height that provides magnetic unevenness with respect to the yoke surfaces of the yoke portions 21a to 21c. Then, the magnetic pole surface of the stator 4 is retracted from the protruding surface of each cassette coil 10, and the protruding portion of each cassette coil 10 is fitted into the yoke portion (concave portion) 21a between the magnetic poles 18 and 19 of each rotor core 17. As described above, the axial gap motor 1a is reduced in axial length (physique) and mass. If the yoke portions of the rotors 3a and 3b are formed only in the vicinity of the back surfaces of the magnetic poles 18 and 19, and the inductance when the rotors 3a and 3b and the stator 4 are not opposed to the magnetic poles can be made sufficiently small, the rotors 3a and 3b The required height of the pole face is also reduced. Therefore, in this case, it is preferable to determine the heights of the magnetic pole surfaces of the stator core 5 and the rotor core 17 in consideration of the moldability of both the stator core 5 and the rotor core 17 of the dust core.

  As described above, in the axial gap motor 1a, the magnetic pole pairs 11 on both the front and back surfaces of each stator core 5 are energized in a lump, so that it is not necessary to concentrate the coil for each magnetic pole or each magnetic pole pair. The number of coils for exciting the stator 4 and the coil mass are reduced. In addition, one cassette coil 10 can be attached to each stator core 5 and can be easily assembled, so that no labor is required and the manufacturing cost is low. Furthermore, there is almost no possibility that the dust core having a low mechanical strength is broken during the operation, and the axial gap motor 1b can be easily manufactured. Further, since each magnetic pole pair 11 of the stator 4 is formed by the magnetic pole 7 on the outer diameter side and the magnetic pole 8 on the inner diameter side of each stator core 5, compared to the case where the magnetic poles 7 and 8 are formed by separate cores. The amount of magnetic flux in the yoke portion 9 between the magnetic poles 7 and 8 of each magnetic pole pair 11 is halved, the yoke thickness in the axial direction of the stator 4 is reduced, and the stator 4 becomes smaller and lighter.

  Accordingly, the magnetic pole pairs 11 on both the front and back surfaces of the stator 4 formed by using the dust core are made magnetically independent on both the front and back surfaces of each stator core 5 of the dust core disposed in the circumferential direction. An axial gap motor 1a is formed by exciting a pair of magnetic poles 11 formed on the front and back surfaces of each stator core 5 by a single cassette coil 10 mounted on a yoke portion 9 of each stator core 5 and formed by magnetic poles 7 and 8. It is possible to provide a novel exciting structure of the stator 4 formed by using a dust core, and to provide an unprecedented axial gap motor 1a that is small, lightweight, easy to manufacture, and capable of obtaining a larger motor output. .

  Each stator core 5 has an outer diameter side magnetic pole 7 protruding longer in the axial direction than an inner diameter side magnetic pole 8. Each stator core 5 has an inner peripheral portion thinner than an outer peripheral portion, and the cassette coil 10 has an inner peripheral portion. Can be easily installed by inserting from the side. In contrast to the stator 4, the rotors 3a and 3b facing both the front and back surfaces of the stator 4 are thinner at the outer peripheral side where the action of centrifugal force is larger than the inner peripheral side, and are stronger against the centrifugal force and rotate at higher speed. Is possible.

  Next, considering that the dimensional error of the core formed of the powder magnetic core is relatively large, each stator core 5 sandwiches one single-sided core 51 and the other single-sided core 52 with a magnetic pole interval adjustment plate 12 interposed therebetween. Therefore, the magnetic pole surfaces on both sides of the stator 4 can be made flat with high accuracy.

(Second Embodiment)
A second embodiment will be described with reference to FIGS. 1, 5, and 6.

  FIG. 5 shows the magnetic pole surface of the stator 4 of the present embodiment. In this embodiment, the connecting method and the energizing direction of the cassette coils 10 by the crossover wires 13 are set appropriately, and each stator core 5 of the stator 4 of FIG. The magnetic poles 7 on the outer diameter side on both the front and back sides are all N poles, and the magnetic poles 8 on the inner diameter side are all S poles. The magnetic poles 7 and 8 may be reversed in polarity. In short, all the magnetic poles 7 are excited to the same polarity, and all the magnetic poles 8 are excited to the same polarity opposite to the polarity of the magnetic poles 7. Furthermore, the gaps of the concave portions formed by the yoke portions 9 on the front and back sides of the stator 4 are used or the concave portions are expanded in the radial direction, and the exciting cassette coil 10 and the front and rear surfaces of the stator 4 are respectively shown on the yoke portion 9. The annular field coils 22a and 22b shown in FIG. 5 are attached, and the field coils 22a and 22b always generate a field having a direction of increasing the magnetic flux. In addition, in order to generate the field magnetic flux of the same direction on the back and front of the stator 4, the energization directions of the field coils 22a and 22b from the terminals a and a and the terminals b and b are reversed. Further, the yoke portions 21a of the rotor cores 17 of the rotors 3a and 3b shown in FIG. 1 also have portions protruding in the axial direction of the field coils 22a and 22b by using the gaps of the recesses or by expanding the recesses in the radial direction. The rotor cores 17 are rotatably fitted in the yoke portions 21a.

  In this case, (1) since the field bias magnetic flux is superimposed on the magnetic flux of the stator 4 by the field coils 22a and 22b, the motor output is further improved. (2) Since the field coils 22a and 22b are simple annular shapes, they are easy to manufacture.

  Therefore, in the case of the present embodiment, the annular field coils 22a and 22b that are easy to manufacture can increase the torque by increasing the magnetic fluxes on both the front and back surfaces of the stator 4 and further improve the motor output of the axial gap motor 1a. .

(Third embodiment)
A third embodiment will be described with reference to FIGS. 7 to 10, the same reference numerals as those in FIGS. 1 to 6 denote the same or corresponding components.

  FIG. 7 shows the axial gap motor 1b of the present embodiment, and FIGS. 8A and 8B show the magnetic pole surfaces of the stator 4 and the rotor 3a. In the axial gap motor 1b of the present embodiment, the magnetic pole pairs 11 on both the front and back surfaces of each stator core 5 of the stator 4 form the magnetic pole pairs 11 of U, V, and W driving phases in order in the circumferential direction.

  The difference between the axial gap motor 1b of the present embodiment and the axial gap motor 1a of the first and second embodiments is that first, the front and back of each stator core 5 is set by setting the energization direction of each cassette coil 10. The polarity of the magnetic pole 7 on the outer diameter side and the magnetic pole 8 on the inner diameter side of each of the magnetic pole pairs of the number of drive phases arranged in order in the circumferential direction (three in the case of the embodiment is three) is This is the opposite point.

  FIG. 9 shows, for example, the polarities of the magnetic pole 7 on the outer diameter side and the magnetic pole 8 on the inner diameter side of each stator core 5, and the magnetic pole pairs 11 of three stator cores 5 of W, U, and V phases adjacent in the circumferential direction are one. Two magnetic pole pair groups # 1 are formed, and the adjacent magnetic pole pairs 11 of the three W, U, and V phase stator cores 5 form the next magnetic pole pair group # 2. # 3 and # 4 are also formed. In the magnetic pole pair 11 of the stator core 5 of the magnetic pole pair group # 1, the magnetic pole 7 is excited to the S pole and the magnetic pole 8 is excited to the N pole. The magnetic pole pairs 11 of the stator core 5 of the adjacent magnetic pole pair group # 2 are all excited with the magnetic pole 7 being an N pole and the magnetic pole 8 being an S pole. Further, the magnetic pole pair 11 of the stator core 5 in the adjacent magnetic pole pair group # 3 is excited to have the magnetic pole 7 as the S pole and the magnetic pole 8 as the N pole, and the magnetic pole pair 11 of the stator core 5 in the adjacent magnetic pole pair group # 4 is In both cases, the magnetic pole 7 is excited to the N pole and the magnetic pole 8 is excited to the S pole. In actuality, since each cassette coil 10 is energized in the order of U, V, and W phases, for example, when the U phase is energized, the magnetic pole 7 of the U phase magnetic pole pair 11 of the magnetic pole pair group # 1 is the S pole, The magnetic pole 8 is excited to the N pole, the magnetic pole 7 of the U-phase magnetic pole pair 11 of the magnetic pole pair group # 2 is excited to the N-pole, and the magnetic pole 8 is excited to the S-pole. The magnetic pole 7 is excited to the S pole, the magnetic pole 8 is excited to the N pole, the magnetic pole 7 of the U-phase magnetic pole pair 11 of the magnetic pole pair group # 4 is excited to the N pole, and the magnetic pole 8 is excited to the S pole.

  That is, when the winding directions of the respective cassette coils 10 are the same, it is simplest and most efficient to connect the cassette coils 10 of the same phase alternately from the upper side and the lower side in the circumferential direction with the crossover wires 13. By connecting, the direction of the magnetic flux generated by energizing each cassette coil 10 of the same phase is alternately reversed in the circumferential direction. Therefore, as described above, when the U-phase is energized, the magnetic pole 7 of the U-phase magnetic pole pair 11 of the magnetic pole pair group # 1 is excited to the S pole and the magnetic pole 8 is excited to the N pole, and the U-phase magnetic pole of the magnetic pole pair group # 2 The magnetic pole 7 of the pair 11 is excited to the N pole, the magnetic pole 8 is excited to the S pole, the magnetic pole 7 of the U-phase magnetic pole pair 11 of the magnetic pole pair group # 3 is excited to the S pole, and the magnetic pole 8 is excited to the N pole. The magnetic pole 7 of the 4 U-phase magnetic pole pair 11 is excited to the N pole and the magnetic pole 8 is excited to the S pole.

  A second difference of the axial gap motor 1b of the present embodiment from the axial gap motor 1a of the first and second embodiments is that the front and back surfaces of the stator 4 are replaced with the field coils 22a and 22b of the second embodiment. Are provided with two annular field coils 22c and 22d for applying a field to each of the magnetic pole pairs 11 on both sides of the magnetic field pairs, and the field coils 22c and 22d intersect each magnetic pole pair 11 of the magnetic pole pair groups # 1 to # 4. In other words, the stator core 5 is disposed so as to be reversed from the front surface to the back surface and vice versa. In addition, the energizing directions of the field coils 22c and 22d are also opposite to those of the field coils 22a and 22b.

  FIG. 10 shows the assembled state in which the field coils 22c and 22d intersect, and the annular field coils 22c and 22d intersect at the boundary between the magnetic pole pair groups # 1 to # 4 and are opposite to each other (not shown). 3) is arranged on the stator so as to be switched from the front surface to the back surface and vice versa.

  Therefore, the field coils 22c and 22d give a magnetic field that enhances the excitation of the magnetic poles 7 and 8 to the magnetic pole pairs 11 on both the front and back surfaces of the stator 4, thereby increasing the torque and improving the motor output. Further, since the polarity direction of the magnetic pole pair is reversed in units of a pair of magnetic pole pairs (units of magnetic pole pair groups # 1 to # 4), the field coils 22c and 22d intersect each other. The number of times (number of times) of reciprocating is as small as four (four times), and an increase in mass due to the field coils 22c and 22d can be suppressed to the minimum electric power.

  Therefore, it is possible to provide a high-performance axial gap motor 1b in which each cassette coil 10 is formed by the same common cassette coil and the connection between them is simplified to increase the torque.

(Fourth embodiment)
A fourth embodiment will be described with reference to FIGS.

  FIG. 11A shows the rotor 3c of the present embodiment that is replaced by the rotors 3b and 3b of the axial gap motors 1a and 1b, and the rotor 3c is disposed to face both the front and back surfaces of the stator 4 of FIG. . The rotor 3 c includes an outer peripheral member 23 and an inner peripheral member 24.

  12 shows the assembly of the rotor 3c, and the outer member 23 has a wedge-shaped outer diameter of a dust core disposed in the circumferential direction and forming a magnetic pole 25 protruding from the outer diameter portion and a yoke portion 26 on the inner diameter side thereof. The side rotor core 27 has a structure in which a nonmagnetic outer peripheral ring 28 is fitted and held on the outer peripheral side, and the inner member 24 is a wedge-shaped dust core disposed in the circumferential direction to form a magnetic pole 29 on the inner diameter side. In this structure, the inner diameter side rotor core 30 is held by fitting a nonmagnetic outer ring 31 on the outer periphery side. Further, the outer member 23 and the inner member 24 are assembled by superimposing the inner member 24 on the magnetic pole surface side of the outer member 23 in the axial direction and fitting a common ring 32 of metal, for example, on the inner peripheral side of the overlapping. The rotor 3c is formed.

  FIG. 13 shows the overlap between the outer diameter side rotor core 27 and the inner diameter side rotor core 30, and the magnetic pole 29 of the inner diameter side rotor core 30 overlaps with the inner peripheral portion of the yoke portion 26 of the outer diameter side rotor core 27. They are connected by a yoke part 26.

  The row 3c configured as described above has a separate structure in which at least the inner diameter side magnetic pole 29 is separated from the outer diameter side magnetic pole 25 and the yoke portion 26, and the inner ring side metal common ring 32 has a separate structure. It is easily integrated and formed by press fitting or the like.

  The row 3c is configured in this way. (1) Centrifugal force due to rotation acts on the rotor 3c, but centrifugal force acts between the salient pole-like magnetic poles 25 and 29 and the concave yoke portion 27. Further, the powder magnetic core has a low Young's modulus, and the amount of deformation due to centrifugal force differs between the outside and the inside of the rotor 3c. In particular, for the inner diameter side magnetic pole 29 that is elongated in the axial direction, the outer diameter side rotor core 27 and the inner diameter side rotor core 30 are separately formed and overlapped to be separated from the yoke portion 27, whereby the amount of deformation described above is achieved. This is because the tensile stress due to the difference between the two can be reduced, and the compression density can be made uniform and mechanically strong. As a result, the rotor 3c can be strong against centrifugal force. In addition, the mold on the side surface of the magnetic pole 29 having a height during the compression molding by the mold of the dust core prevents the rotor magnetic poles 25 and 26 from being damaged by rubbing against a punch that has received a lateral force from the side surface. Productivity can be improved by making the mold less likely to be damaged than when integrally molded with a dust core. (2) The reason why the inner diameter side rotor core 30 is held by the outer ring 31 made of a non-magnetic material is to first reliably hold the inner diameter side rotor core 30 with the force in the compression direction against the centrifugal force. Further, the stator facing the rotor 3c is assumed to have the polarity direction of the magnetic pole pair reversed in units of the magnetic pole pair groups # 1 to # 4 as in the stator 4 of the third embodiment. The direction of the passing magnetic flux differs depending on the magnetic pole pairs of the magnetic poles 25 and 29 at the locations facing the exciting magnetic pole pairs 11 of the magnetic pole pair groups # 1 to # 4 as indicated by the wavy arrows in FIG. Moreover, the number of magnetic pole pairs 11 of each phase of the stator is an even number (specifically, four). For this reason, as shown in FIG. 11B, in the outer ring 31 that holds the inner rotor core 30 (which can be regarded as a loop coil with respect to the magnetic flux), the interlinkage magnetic flux indicated by the arrow line is canceled, and the inner rotor core 30 This is because no induction current is generated in the outer peripheral ring 31 that holds the electromagnetic wave and electromagnetic induction can be prevented.

  Therefore, by using the rotor 3c of this embodiment instead of the rotor of an axial gap motor having a structure like the axial gap motor 1b having the configuration of the third embodiment, a rotor that receives centrifugal force can be accurately formed. The motor performance can be further improved, and the inner ring-side common ring 32 is made of metal or the like, so that the common ring 32 can be easily fitted by press-fitting or the like to hold both the rotor cores 27 and 30 together. Can do.

  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 rotors 3a, 3b, 3c The number of the magnetic pole pairs and the magnetic pole pairs 11 of the stator 4 is not limited to eight or twelve. Also, the number of drive phases is not limited to three. Furthermore, the shape of each of the cores 5, 27, 30, 51, 52 and the magnetic poles 7, 8, 25, 29 is not limited to the shape of each embodiment. Further, the structure and shape of each cassette coil 10 may be any.

  Next, in the first to third embodiments, the rotor does not have to be formed of a dust core. In the fourth embodiment, the stator may not be formed of a dust core.

  Next, for example, a plurality of configurations of the rotor 3a, the stator 4, and the rotor 3b of the first embodiment can be combined to form a so-called multistage configuration, and the same applies to other embodiments. In these cases, the same effects as in the above embodiments can be obtained.

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

DESCRIPTION OF SYMBOLS 1a, 1b Axial gap motor 3a, 3b, 3c Rotor 4 Stator 5 Stator core 10 Cassette coil 11 Magnetic pole pair 12 Adjustment plate 22a-22d Field coil 26 Outer diameter side rotor core 28 Outer ring 30 Inner diameter side rotor core 31 Outer circumference which holds inner rotor core Ring 32 Common ring 51, 52 Single-sided core

Claims (6)

A stator in which a plurality of magnetic pole pairs formed by an outer diameter side magnetic pole and an inner diameter side magnetic pole are arranged in the circumferential direction on both the front and back surfaces in the axial direction, and a rotor disposed to face both the front and back surfaces of the stator, An axial gap motor with
The stator is
A plurality of wedge-shaped stator cores formed of powder magnetic cores are formed by being arranged in the circumferential direction in a magnetically independent state with gaps,
The radially outer diameter side portions of the front and back surfaces of each stator core form the outer diameter side magnetic pole,
The radially inner diameter side portions of the front and back surfaces of each stator core form the inner diameter side magnetic pole,
Axial coil characterized in that a cassette coil for energizing the pair of magnetic poles on both the front and back surfaces together is mounted on a yoke portion between the outer diameter side magnetic pole and the inner diameter side magnetic pole of each stator core. Gap motor. The axial gap motor according to claim 1,
In each of the stator cores, the outer diameter side magnetic pole is formed longer in the axial direction than the inner diameter side magnetic pole. The axial gap motor according to claim 1 or 2,
Each stator core is formed by joining one single-sided core and the other single-sided core back to back with an adjustment plate for the magnetic pole interval interposed therebetween. In the axial gap motor in any one of Claims 1-3,
An axial gap motor, wherein annular field coils are arranged on both the front and back surfaces of the stator. In the axial gap motor in any one of Claims 1-3,
Each pair of magnetic poles on both the front and back sides of each stator core forms a pair of magnetic poles for each driving phase in the circumferential direction in order,
The polarity of the magnetic pole on the outer diameter side and the magnetic pole on the inner diameter side is reversed for each magnetic pole pair group of the number of phases of the driving phase sequentially arranged in the circumferential direction,
A plurality of annular field coils for applying a field to each of the magnetic pole pairs on both sides of the stator;
The axial gap motor according to claim 1, wherein the field coils on both sides are arranged on the stator so as to cross each magnetic pole pair group and to be reversed from each other to reverse from the front surface to the back surface of the stator. In the axial gap motor according to any one of claims 1 to 5,
The rotor arranged to face both the front and back surfaces of the stator,
A wedge-shaped outer-diameter-side rotor core of a dust core that is arranged in the circumferential direction and forms a magnetic pole on the outer diameter side, and a wedge-shaped inner peripheral portion of a dust core that is arranged in the circumferential direction and forms a magnetic pole on the inner diameter side The side rotor core is individually held by fitting a non-magnetic outer ring on each outer peripheral side,
An axial gap motor characterized in that the two rotor cores are overlapped in the axial direction and assembled by fitting a common ring on the inner peripheral side of the two rotor cores.

Images