JP2011072087A - Axial gap motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lightweight, small-sized, and robust axial gap motor with a novel rotor structure in which a rotor is placed on both end face sides of a stator, wherein it is possible to prevent production of eddy current and induced current and ensure a sufficient magnetic path. <P>SOLUTION: Dust cores 34 are arranged as multiple rotor magnetic poles in the direction of circumference of each of stator 3a, 3b arranged on both sides of a rotor 2 opposite to the stator 2. A magnetic path between the rotors 3a, 3b is formed by a magnetic path formation member 4 penetrating the center hole 21 in the stator 2. Magnetic paths between the dust cores 34 are formed of a laminated steel plate body 35. Part of the laminated steel plate body 35 around each dust core 34 is cut into a gap shape to expose part of the circumferential surface of each dust core 34 from the laminated steel plate body 35 and an axial gap motor 1 is thereby formed. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an axial gap motor in which a rotor is disposed on both end surfaces of a stator, and more particularly to a reduction in size and weight of a rotor that realizes a lightweight, small and robust configuration.

  Conventionally, in a radial type switched reluctance motor, a stator and a rotor are arranged concentrically in a radial direction with respect to a motor shaft.

  FIGS. 10A to 10C are sectional views showing the structure and operation of a three-phase U, V, W switched reluctance motor 100. As shown in these drawings, the switched reluctance motor 100 is a motor shaft. Rotor magnetic poles (saliency poles) 111 are arranged at equal intervals in the circumferential direction on a rotor 110 that is axially attached to a rotor 110 (not shown), and a plurality of magnetic poles 111 are arranged on the inner peripheral side of the outer stator 120 so as to face the rotor magnetic pole 111. The stator magnetic pole 121 is arranged. Each stator magnetic pole 121 is concentratedly wound with a coil 122 of the corresponding phase so that the N pole and S pole of each phase are alternately excited.

  Then, when the coil 122 concentratedly wound on each stator magnetic pole is excited in phase sequence, the rotor magnetic pole 111 in the vicinity thereof is magnetically attracted, torque is generated, the rotor 110 rotates, and the excitation phases are sequentially switched. The rotation of the rotor 110 continues and the switched reluctance motor 100 rotates. At this time, as the excitation phase is switched, the magnetic path changes as shown by the loop-shaped arrow lines in FIGS. 10A to 10C (FIG. 10A is the U phase, and FIG. 10B is the V phase). Phase, (c) is the W phase). The arrow line t indicates torque (magnetic attraction force), and the arrow line r at the center indicates the motor rotation direction.

  In such a switched reluctance motor 100, only half of the rotor magnetic poles 111 are used at a certain moment, and the remaining half of the rotor magnetic poles 111 are in an empty state (a state in which no magnetic flux passes) in preparation for the next excitation. become. Therefore, if a sufficient output is obtained, it becomes large and heavy.

  On the other hand, when an axial gap motor is provided with one rotor and one stator, each of the rotor magnetic pole and the stator magnetic pole is arranged in the circumferential direction on the end face side where the rotor and the stator face each other. When the concentrated winding coil of the stator magnetic pole is energized and excited in order, the rotor rotates and the motor shaft rotates in accordance with the magnetic action of the stator magnetic pole and the rotor magnetic pole.

  The axial gap motor has the advantage that the increase in the axial length accompanying the increase in output is smaller than that of the radial switched reluctance motor 100, and is lighter and smaller than the switched reluctance motor 100. Various proposals have been made for this type of axial gap motor, which is useful for motors and the like, and which is further lightened and reduced in size and has a robust structure resistant to centrifugal force.

  For example, each rotor magnetic pole is formed of a permanent magnet, and the rotor is composed of the permanent magnet of each rotor magnetic pole, the frame, and the rotor core, and the rotor is thinned to be strong against centrifugal force. At this time, in order to increase the output with a small configuration, the rotor magnetic poles are disposed in the circumferential direction on one end surface side of the rotor in the axial direction, and the stator is disposed on both end surface sides of the rotor. On the contrary, it has been proposed to dispose a stator magnetic pole in the circumferential direction on one end surface side of the stator in the axial direction and to dispose a rotor on both end surface sides of the stator (for example, Patent Document 1 (Summary)). , Paragraphs [0031], [0054], FIG. 1, FIG. 2, etc.)).

  FIG. 11 is a disassembled perspective view showing the rotor structure described in Patent Document 1, and the rotor 200 has one rotor core 240 and both sides so as to sandwich the rotor core 240 in order to dispose a stator on both end surfaces. The two frame members 241 and 242 provided and permanent magnets 243 and 244 provided in the plurality of magnet mold holes 241a and 242a of the frame members 241 and 242 respectively.

  In this case, since the rotor core 240 and the frame member 241 share the centrifugal force acting on the permanent magnet 243, a robust structure is obtained. Further, since the size of the permanent magnets 243 and 244 can be increased while reducing the thickness of the rotor core 240, the motor is lightweight, small, and has high output.

  Next, the applicant of the present application has already filed an application for an axial gap motor having a structure in which a stator is disposed on both end faces of a rotor (Japanese Patent Application No. 2009-011523).

  FIG. 12 shows the structure of the already-applied three-phase drive axial gap motor 300. In the axial gap motor 300, rotors 320 and 330 are arranged on both end surfaces of the stator 310, and the rotor magnetic poles 321 and 331 are made of a soft magnetic material. It is a salient pole structure formed by, for example.

  In the axial gap motor 300, stator magnetic poles 311 and 312 of each phase are arranged in the circumferential direction on one end face and the other end face in the axial direction of the stator 310, and the concentrated winding coils (see FIG. (Not shown), the stator magnetic poles 311 of each phase on one end face are excited to the N pole, and the stator magnetic poles 312 of each phase on the other end face are excited to the S pole in phase order. Further, rotors 320 and 330 are arranged on both sides of the stator 310 so as to face the stator 310, and the rotors 320 and 330 are each provided with a plurality of rotor magnetic poles 321 and 331 having a salient pole configuration in the circumferential direction. Further, a magnetic path between the rotors 320 and 330 is formed by an annular magnetic path forming member 340 loosely inserted into the center hole of the stator 310.

  Then, the concentrated winding coils of the stator magnetic poles 311 and 312 on both end faces of the stator 310 are energized and excited in sequence, whereby the stator 310 is excited to the N pole while the magnetic pole position on one end face moves in the circumferential direction. The magnetic pole position of the other end face moves in the circumferential direction and is excited to the S pole, and the rotors 320 and 330 are rotated by the magnetic action of the rotor magnetic poles 321 and 331 facing the stator magnetic poles 311 and 312.

JP 2006-14563 A

  In the case of the conventional axial gap motor described in Patent Document 1, the rotor 200 of FIG. 11 has a frame member 241 when the frame members 241 and 242 provided on the rotor core 240 are electrical conductors (stainless steel or the like). 242 is a short-circuit ring surrounding the rotor magnetic poles of the permanent magnets 243 and 244. In this case, problems such as induction current for suppressing fluctuations in magnetic flux in the frame members 241 and 242 are generated and the frame members 241 and 242 generate heat, and increase in magnetic flux is suppressed and torque is reduced.

  Further, the permanent magnets 243 and 244 serving as the rotor magnetic poles have different magnetic polarities from the neighboring permanent magnets 243 and 244 in the circumferential direction, and the rotor magnetic poles on one and the other end surfaces of the rotor 200 are N and S poles in the circumferential direction. (See paragraph [0011] etc. of Patent Document 1). In this case, the yoke portion of the stator must be made quite thick so that magnetic saturation does not occur, and the motor becomes thick in the axial direction, becomes large and increases in weight. For this reason, the axial gap motor cannot be made sufficiently light and small.

  Next, in the case of the axial gap motor 300 of the already-filed application in FIG. 12, all of the stator magnetic poles 311 on one end face side of the stator 310 are excited to, for example, N poles, and all of the stator magnetic poles 312 on the other end face side of the stator 310 are Is excited to the south pole. In addition, the magnetic flux from the N pole to the S pole passes through the magnetic path of the magnetic path forming member 340. In this case, when the arrangement of the stator magnetic poles 311 and 312 on the both end face sides of the stator 310 is shifted in the circumferential direction, an equivalent state is obtained in which the total number of magnetic poles of the stator 310 is doubled. Therefore, downsizing (thinning) and weight reduction can be realized. However, in particular, in the rotors 320 and 330, the magnetic flux of the excitation phase is such that the rotor magnetic poles 321 and 331 opposed to the stator magnetic pole of the excitation phase form a magnetic path in the axial direction (magnetic pole back direction). Therefore, in order to ensure a sufficient magnetic path, the rotor magnetic poles 321 and 331 cannot be made too small. Further, the magnetic flux passing through the opposing rotor magnetic poles 321 and 331 is transmitted to the magnetic path forming member via the yoke portion. At this time, depending on the material of the yoke portion, eddy current loss or the like may occur. Further, when the rotor magnetic poles 321 and 331 are supported by a frame body such as the frame members 241 and 242, problems such as the induced current occur.

  The present invention relates to an axial gap motor having a structure in which rotors are arranged on both end surfaces of a stator, and is a novel lightweight, small, and robust rotor capable of preventing eddy currents and induction currents and securing a sufficient magnetic path. It is an object to provide an axial gap motor having a structure.

  In order to achieve the above-described object, the axial gap motor of the present invention is arranged such that each stator magnetic pole arranged circumferentially on one end face in the axial direction has N poles and circumferentially arranged on the other end face in the axial direction. A stator having a coil for exciting each stator magnetic pole to the S pole, a rotor disposed on both sides of the stator so as to face the stator, and a plurality of rotor magnetic poles disposed in the circumferential direction, and a center hole of the stator An axial gap motor including a magnetic path forming member that forms a magnetic path between the two rotors, the two rotors each having a dust core disposed in the circumferential direction as each rotor magnetic pole, A laminated steel plate body that forms a magnetic path between the dust cores, and the laminated steel plate body is partially cut out in the form of a gap around each of the dust cores, and the peripheral surface of each dust core Part of the laminate It is characterized in that it is exposed from the plate body (claim 1).

  In the axial gap motor of the present invention, the radially outer portion of each of the dust cores of the two rotors is connected to the radially outer portion of the adjacent dust core through the laminated steel sheet body. It is said. (Claim 2).

  In the axial gap motor of the present invention, at least the radially inner ends of the dust cores of the rotors protrude radially inward from the radially inner ends of the opposing stator magnetic poles. (Claim 3).

  Furthermore, the axial gap motor of the present invention includes a rotor housing in which the two rotors hold the laminated steel plate body and the dust cores in a lid shape, and the laminated steel plate and the rotor housing are each of the dust cores. Each of the surrounding portions has a gap (Claim 4).

  In the case of the axial gap motor of the present invention according to claim 1, since the portion that is susceptible to fluctuations in the magnetic flux of each rotor magnetic pole is formed by a dust core that is a non-directional magnetic material, each rotor magnetic pole is Thus, the magnetic flux of the excitation phase passes through the rotor magnetic pole facing the stator magnetic pole of the excitation phase in the axial direction (magnetic pole back direction), and is It is bent 90 degrees by the non-directionality of the powder magnetic core, is distributed in a plane shape to each layer of the laminated steel sheet body, and is transmitted to the rotor magnetic poles facing the nearby non-excited phase without generating eddy currents. Further, a magnetic path between the rotors of the magnetic flux passing through these rotor magnetic poles is formed by the magnetic path forming member. In this case, in both rotors, not only the rotor magnetic pole facing the excitation phase but also the rotor magnetic pole facing the non-excitation phase in the vicinity thereof forms a magnetic path. Can be ensured, and the entire rotor and motor can be dramatically reduced in size.

  In addition, a part of the periphery of each of the dust cores of the laminated steel sheet is notched in a gap shape, and a part of the peripheral surface of each dust core is exposed from the laminated steel sheet. A short ring that surrounds the rotor magnetic pole of the powder magnetic core is not provided, and the generation of induced current is prevented, and problems such as torque reduction do not occur.

  Furthermore, the laminated steel plate can be formed of a robust electromagnetic steel plate or the like, and the rotor magnetic pole of the dust core is held by the robust laminated steel plate, so that the rotor structure is robust against centrifugal force and the like.

  Therefore, in an axial gap motor having a structure in which the rotor is arranged on both end surfaces of the stator, a light, small, and robust new rotor structure that can prevent eddy currents and induction currents and secure a sufficient magnetic path. An axial gap motor can be provided.

  In the case of the axial gap motor of the present invention according to claim 2, in both rotors, the radially outer portion of the dust core of each rotor magnetic pole is also the radially outer portion of the dust core of the adjacent rotor magnetic pole through the laminated steel plate body. Therefore, the portion also forms a solid magnetic path, and accordingly, the thickness of a portion such as a yoke connecting the rotor magnetic poles can be reduced. Therefore, there is an advantage that the rotor and the motor can be further reduced in size. In this case as well, since the laminated steel sheet body is partially cut out in the form of a gap, no eddy current is generated. Further, although the outer diameter of the rotor is increased, the stator is originally wound with a coil rather than the rotor, so that the thickness of the stator becomes larger, so that the entire motor does not increase.

  In the case of the axial gap motor of the present invention according to claim 3, at least the radially inner end of the dust core as the rotor magnetic poles of both rotors is radially inward of the stator magnetic poles on the other end face of the opposing stator. Since it protrudes inward in the radial direction from the end portion, the fringing magnetic flux of the stator magnetic pole can be received by the rotor magnetic pole without leakage, and the generation of eddy currents on the surface of the laminated steel sheet body due to the fringing magnetic flux can also be prevented. There are advantages you can do.

  In the case of the axial gap motor of the present invention according to claim 4, the laminated steel plate body and the dust cores are held and fixed by the rotor housing so as not to be separated, and both rotors are formed more firmly. In addition, since there is a gap between the laminated steel plate and the rotor housing around each rotor magnetic pole, the conduction loop that generates the induced current is reliably cut off, and the rotor housing does not cause torque reduction or loss increase.

It is the disassembled perspective view which abbreviate | omitted a part of axial gap motor of the 1st Embodiment of this invention. (A), (b) is the perspective view of the rotor of FIG. 1, and a front view. It is a perspective view explaining the magnetic path of the rotor of FIG. (A), (b) is sectional drawing explaining the fringing magnetic flux of the axial gap motor of FIG. 1, and the one part enlarged view. (A), (b) is the perspective view of the rotor of the 2nd Embodiment of this invention, and a front view. It is explanatory drawing of the rotor of the 3rd Embodiment of this invention. It is explanatory drawing of the example of attachment of the rotor of FIG. (A)-(c) is explanatory drawing of the detailed structure of the rotor of FIG. FIG. 7 is an enlarged perspective view of a part of the rotor of FIG. 6. (A)-(c) is explanatory drawing of the conventional switched reluctance motor. It is explanatory drawing of the conventional axial gap motor. It is explanatory drawing of the other 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)
A first embodiment will be described with reference to FIGS.

(Constitution)
FIG. 1 shows an axial gap motor 1 of a three-phase drive according to this embodiment. The axial gap motor 1 includes a disk-shaped stator 2 in which a motor shaft (not shown) is loosely inserted into a center hole 21, and both end faces thereof. Two disk-shaped rotors 3a and 3b disposed on the side facing the stator 2 and a magnetic path between the rotors 3a and 3b, which is attached to the motor shaft in a jacket shape and penetrates the center hole 21 of the stator 2. And a magnetic path forming member 4 as an axial magnetic path material made of a hollow tubular magnetic material.

  In the stator 2, a plurality of stator magnetic poles 23 having salient pole structures are arranged at equal intervals in the circumferential direction on both end faces of a disk-shaped thin stator yoke 22 made of, for example, laminated steel sheets (electromagnetic steel sheets). Each stator magnetic pole 23 is a magnetic pole in the phase sequence of U, V, W, U, V, W,..., And a coil (not shown) of the corresponding phase is concentratedly wound. Then, by energization control of the coils of each stator magnetic pole 23, for example, each stator magnetic pole 23 on one end face on the motor shaft end side is all excited to N pole, and each stator magnetic pole 23 on the other end face on the motor shaft output side All are excited to the S pole. At this time, the stator magnetic poles 23 on the one end face side and the stator magnetic poles 23 on the other end face side are arranged so as not to overlap each other when viewed from the motor axial direction. The number of magnetic poles is twice that of the case where the stator magnetic poles 23 are arranged only on one end face.

  The rotors 3a and 3b have substantially the same configuration. For example, a motor shaft having a magnetic path forming member 4 mounted in a center hole 32 of a disk-shaped rotor yoke 31 of a laminated steel plate (electromagnetic steel plate) is fitted into the stator 2 of the rotor yoke 31. A magnetic pole portion 33 having a gear shape in a plan view is provided concentrically with the center hole 32 on the opposite end face side.

  2 (a) and 2 (b) show the rotor 3b. As is clear from these drawings, the magnetic pole portions 33 of the rotors 3a and 3b are arranged at equal intervals in the circumferential direction in the radially outer portion of the rotor yoke 31. A dust core 34 as each rotor magnetic pole disposed, and a laminated steel plate body 35 that forms a magnetic path between the dust cores 34 together with the rotor yoke 31 are provided.

  Each dust core 34 is a magnetic core of a non-directional magnetic material obtained by compression molding magnetic powder having an insulating film. In the laminated steel plate 35, each support frame portion 35b radially extending radially outward from the radially inner gear-shaped inner portion 35a surrounds and holds each dust core 34. It is a shape fitted radially, and is formed of the same laminated steel plate as the rotor yoke 31. In order to reduce the weight of the rotor yoke 31, a portion between the powder magnetic cores 34 is partially cut to form a hole 31a.

  Furthermore, a part of the periphery of each dust core 34 of the laminated steel body 35 is cut out in a gap shape, and a part of the peripheral surface of each dust core 34 is exposed from the laminated steel body 35. The portion notched in the gap shape may be an arbitrary portion around each of the dust cores 34. However, in the present embodiment, the portion notched in the gap shape is a circumferentially outer periphery of each dust core 34. A notch 36 is formed in this portion, and each dust core 34 is exposed from the laminated steel plate body 35.

  Note that the laminated steel plate body 35 and the rotor yoke 31 are magnetically connected integrally with the annular radially outer end surface in contact with the magnetic path forming member 4 fitted in the center hole 32 of the rotor 3a, 3b.

(Operation)
In the axial gap motor 1 configured as described above, the stator magnetic poles 23 of the respective phases on both end faces of the stator 2 are excited such that the magnetic pole position moves in the circumferential direction by energization of the coil. At this time, basically, as indicated by the arrow line in FIG. 1, the magnetic flux emitted from the N-pole stator magnetic pole 23 of the excitation phase of the stator 2 is compressed as a rotor magnetic pole of the rotor 3 a facing the magnetic pole 23. From the magnetic core 34, through the laminated steel plate 35 and the magnetic path forming member 4, toward the rotor 3b, and from the dust core 34 as the rotor magnetic pole of the rotor 3b facing the S magnetic pole 23 of the excitation phase of the stator 2, The stator 2 passes through the S-phase stator pole 23 of the excitation phase and returns to the N-phase stator pole 23 of the excitation phase. At that time, the rotor 3a, 3b is rotated by the magnetic action of the stator magnetic pole 23 of the stator 2 and the rotor magnetic pole formed by the dust core 34 opposed to the rotor 3a, 3b, the motor shaft is rotated, and the motor output Will occur.

  By the way, each rotor magnetic pole of the magnetic pole portion 33 of the rotors 3a and 3b is formed by a dust core 34, which is a non-directional magnetic material in a portion that is susceptible to magnetic flux fluctuations. Each rotor magnetic pole extends radially inward by the inner portion 35 a of the laminated steel plate 35 and is connected to the magnetic path forming member 4. Further, the rotor magnetic poles of the magnetic pole portions 33 of the rotors 3 a and 3 b are connected to each other by the rotor yoke 31 at the back surfaces of the magnetic poles. Therefore, the magnetic flux of the excitation phase passes through the rotor magnetic pole facing the stator magnetic pole 23 of the excitation phase in the motor axis direction (magnetic pole back direction), and at that time, it is bent by 90 degrees due to the non-directionality of the dust core 34 and laminated. It is distributed in a planar manner to each layer of the steel plate body 35 and is transmitted to the dust core 34 of the rotor pole of the nearby non-excited phase without generating eddy currents.

  FIG. 3 shows the three-dimensional spread of the magnetic flux of the rotor 3a by an arrow line, and the magnetic flux of the solid arrow line entering the dust core 34 of the rotor magnetic pole facing the stator magnetic pole 23 of the excitation phase is shown by the broken arrow line. Further, the magnetic core 34 of the rotor magnetic pole facing the non-excited phase stator magnetic pole 23 passes through the laminated steel plate 35, and the magnetic flux passing through these three-dimensional magnetic paths passes to the magnetic path forming member 4 on the radially inner side. Head.

  And the same solid magnetic path is formed also about the rotor 3b, and a magnetic path is formed in the direction of the arrow line opposite to FIG.

  In this case, in the rotors 3a and 3b, not only the rotor magnetic pole facing the excitation phase but also the rotor magnetic pole in the vicinity thereof forms a magnetic path for the magnetic flux, so that the rotor magnetic pole can be made sufficiently small to secure a sufficient magnetic path for the rotor. The thickness and area of the rotors 3a and 3b can be reduced. As a result, the entire motor can be dramatically reduced in size.

  Further, a part of the periphery of each of the dust cores 34 of the laminated steel body 35 is cut out in a gap shape, and a part of the peripheral surface of each dust core 34 is exposed from the laminate steel sheet 35. The steel plate body 35 does not become a short-circuit ring surrounding the rotor magnetic poles of the dust core 34, and the generation of induced current is prevented and problems such as torque reduction do not occur.

  Further, since the laminated steel plate body 35 is formed of a robust electromagnetic steel plate, and the rotor magnetic pole of the dust core 34 is held by the robust laminated steel plate body 35, the axial gap motor 1 has a robust rotor structure against centrifugal force and the like. become.

  Therefore, in the case of this embodiment, the rotors 3a and 3b are arranged on both end surfaces of the stator 2, and the light weight, small size, which can prevent the generation of eddy currents and induced currents and secure a sufficient magnetic path, In addition, the axial gap motor 1 having a new and robust rotor structure can be provided.

  Further, in the magnetic pole part 33 of the rotors 3a and 3b, the magnetic pole width of each rotor magnetic pole extended radially inward by the laminated steel plate body 35 gradually increases in the vicinity of the outer peripheral surface of the magnetic path forming member 4, and the magnetic path forming member Since the rotor magnetic poles are connected to each other in an annular shape on the outer peripheral surface of No. 4, the magnetic flux distribution on the outer peripheral surface of the magnetic path forming member 4 is smoothed. The accompanying torque drop can also be prevented.

  By the way, in the axial gap motor 1, the radially inner ends of the dust cores 34 of the rotors 3 a and 3 b protrude more radially inward than the radially inner ends of the opposing stator magnetic poles 23.

  4A shows the assembled state of the axial gap motor 1. In FIG. 4, 24 is a coil concentratedly wound around the stator magnetic pole 23, 5 is a motor shaft, 51 and 52 are retaining rings of the motor shaft 5. FIG. is there.

  4B is an enlarged view of the radially inner end of the stator 2 and the rotor 3b surrounded by the annular solid line α in FIG. 4A, and the radial direction of the dust core 34 as the rotor magnetic pole of the rotor 3b. The inner end portion extends and projects inward (center hole side) from the radially inner end portion of the opposing stator magnetic pole 23 by a length indicated by z in the drawing.

  Therefore, among the magnetic fluxes indicated by broken lines in FIG. 4B, in particular, the fringing magnetic flux at the radially inner end of the stator magnetic pole 23 can be received by the dust magnetic core 34 of the rotor magnetic pole without leakage, and the rotors 3a, 3b. The magnetic flux passing therethrough increases, the torque increases, the motor output increases, and the generation of eddy currents due to the fringing magnetic flux passing through the surface of the laminated steel plates of the rotor yoke 31 and the laminated steel plate body 35 can be prevented. There is also an advantage that can be done.

  For the rotor yoke 31 as well, it is preferable that the radially inner end is extended to the outer periphery of the magnetic path forming member 4 and used as a magnetic path. Also, the dust cores 34 of both rotors 3a and 3b are extended radially outward so that the fringing magnetic flux at the radially outer end of the stator pole 23 is received by the dust core 34 of the rotor pole without leakage. Also good.

(Second Embodiment)
A second embodiment will be described with reference to FIGS.

  In the present embodiment, instead of the rotors 3a and 3b in FIG. 1, the diameter of the adjacent dust core 34 via the laminated steel plate body 37 in which the radially outer portion of each dust core 34 corresponds to the laminated steel plate body 35 is used. The rotor 3 c connected to the outer side portion in the direction is disposed on both end surfaces of the stator 2 to form an axial gap motor similar to the axial gap motor 1.

  5 (a) and 5 (b) show the rotor 3c, and the laminated steel plate body 37 of the rotor 3c is roughly a rotor as is apparent from a comparison with the rotor 3b of FIGS. 2 (a) and 2 (b), for example. Each laminated steel plate body 35a is connected to the laminated steel plate body 3b of 3b so that the radially outer sides of the adjacent dust cores 34 are connected in an arch shape. Each laminated steel sheet body 35a has an arm shape projecting outward in the radial direction in a U shape in plan view, and the left and right end faces abut on the side closer to the notch 36 on the radially outer side of the adjacent dust core 34. . Therefore, each powder magnetic core 34 has a notch 36 exposed from the laminated steel plate body 37, and the laminated steel plate body 37 is a short-circuit ring surrounding the rotor magnetic pole of the dust magnetic core 34, as in the case of the laminated steel plate body 35. Thus, the generation of induced current is prevented, and problems such as torque reduction do not occur.

  Then, the rotor 3c is extended by the laminated steel plate body 37 so that the rotor magnetic poles extend radially outward of the dust cores 34, and the amount of magnetic flux passing is further increased, making it thinner and smaller. Further reduction in the size of the axial gap motor can be achieved.

  The outer diameter of the rotor 3c is larger than that of the rotors 3a and 3b, but the stator 2 is larger than the rotors 3a and 3b by winding the coil 23. Don't be.

(Third embodiment)
A third embodiment will be described with reference to FIGS. 1 and 6 to 9.

  In the present embodiment, instead of the rotors 3a and 3b in FIG. 1, the rotor 3d having a rotor housing 6 is disposed on both end surfaces of the stator 2 to form an axial gap motor similar to the axial gap motor 1. To do.

  The rotor 3d is formed by holding a laminated steel plate 35 and each dust core 34 integrally formed with the rotor yoke 31 of the rotors 3a and 3b in a lid-like rotor housing 6.

  FIG. 6 shows the structure of the rotor 3 d, in which a dust core 34 is fitted into each support frame portion 35 b of a laminated steel plate body 35 formed integrally with the rotor yoke 31. Each powder magnetic core 34 has a back surface that is recessed for the purpose of balance adjustment and weight reduction described later. Further, a laminated steel plate body 35 in which the dust core 34 is fitted is fitted in a lid-like rotor housing 6 formed by processing, for example, an iron plate. At this time, the rotor yoke 31 integral with the laminated steel plate body 35 is pressed into the rotor housing 6 by the plurality of locking claws 6 a bent inside the peripheral portion of the rotor housing 6. It is firmly fixed inside. In addition, a locking piece 6b serving as a holding wall of each dust core 34 is formed at a portion of the outer portion of each dust core 34 on the peripheral portion of the rotor housing 6, and each locking piece 6b is each dust core 34. The respective powder magnetic cores 34 are also firmly held in contact with the outer surface. The bottom surface of the rotor housing 6 has a center hole 6c through which the motor shaft 5 passes, a plurality of mounting holes 6d in the vicinity of the periphery, and a cutout opening 6e between the dust cores 34 for the purpose of weight reduction and the like. Is formed.

  The rotor 3d formed in this way is combined into an annular shape by the rotor housing 6 serving as an end plate so that a plurality of parts of the laminated steel plate 35 and the dust cores 34 formed integrally with the rotor yoke 31 are not separated. Can be held and fixed to form a robust rotor 3c. At this time, there is also an advantage that the magnetic pole can be easily positioned by the rotor housing 6. Further, since each dust core 34 fitted in the laminated steel plate 35 is held with a compressive force advantageous in terms of mechanical strength, there is also an effect of preventing damage (scattering).

  Next, the rotor 3 d can be easily attached to the motor shaft 5 by screwing each attachment hole 6 d on the bottom surface of the rotor housing 6.

  FIG. 7 shows an example of attachment of the rotor 3d. Screws 7a communicated with the respective attachment holes 6d on the bottom surface of the rotor housing 6 are screwed into the respective screw holes 7b on the outer peripheral edge of the stepped portion of the rotor position of the motor shaft 5. By doing so, the rotor 3c can be securely attached to the motor shaft 5.

  In addition, since the laminated steel plate 35 and the locking piece 6b of the rotor housing 6 have a gap 8 in a portion around each rotor magnetic pole of the rotor 3d, that is, a portion on the radially outer peripheral surface of each dust core 34. The outer peripheral surface of each powder magnetic core 34 is partially exposed, the conduction loop that generates the induced current is reliably cut off, and the rotor housing 6 does not cause torque reduction or loss increase.

  8A and 8B are perspective views of the rotor 3d viewed from the opening surface side and the bottom surface side of the rotor housing 6, respectively. FIG. 8C is a pressure indicated by a broken line circle in FIG. 3 is an enlarged perspective view of a portion of the outer peripheral surface of the powder magnetic core 34. FIG. As is apparent from these drawings, in the portion of the outer peripheral surface of the dust core 34, there are left and right gaps 8 between the laminated steel plate body 35 and the locking pieces 6 b of the rotor housing 6, and the dust core 34. The peripheral surface is not completely covered with a conductor.

  Therefore, as described above, in the rotor 3d, the conduction loop that generates the induced current is reliably cut off at each portion of the powder magnetic core 34, and the rotor housing 6 does not cause a decrease in torque or an increase in loss.

  Next, each of the dust cores 34 has a recessed back surface for the purpose of balance adjustment and weight reduction.

  FIG. 9 is an enlarged perspective view of the portion of the outer peripheral surface of the dust core 34 indicated by the broken-line circle in FIG. 8A, and shows an example of a recess on the back side of the dust core 34.

  By doing so, the rotor 3d has an advantage that the magnetic imbalance can be corrected so as not to disturb the magnetic circuit.

  By the way, a portion extending in the inner peripheral direction of the rotor housing 6 can be used as a magnetic circuit. In this case, an improvement in motor performance due to relaxation of magnetic saturation and a weight reduction effect due to a reduction in yoke thickness occur.

  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 shape of each dust core 34 Further, the number and the shape of the laminated steel plates 35 and 37 are not limited to those of the above embodiments.

  Moreover, the thickness of the laminated steel plates 35 and 37 is not necessarily the thickness that covers the entire side surface of the dust core 34, and may be, for example, a portion that covers half or less.

  Further, a part of the gap-shaped notch 36 around each of the dust cores 34 of the laminated steel bodies 35 and 37 may be an arbitrary part around each of the dust cores 34, and may be formed on the outer surface portion. It is not limited.

  Next, for example, the stator 2 according to the first embodiment, the rotors 3a and 3b, and the magnetic path forming member 4 are combined in a plurality, with the arrangement of the stator 2 and the rotors 3a and 3b reversed, so-called multistage configuration. In this case, the same effect as the embodiment can be obtained.

  Of course, the axial gap motor of the present invention may be configured to be driven in multiple phases of four or more phases. Further, the number of magnetic poles and the like of the stator 2 and the rotors 3a to 3d are not limited to those in the above embodiments. Furthermore, the magnetic poles on both end faces of the stay 2 may be opposite to those in 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.

DESCRIPTION OF SYMBOLS 1 Axial gap motor 2 Stator 3a-3d Rotor 4 Magnetic path formation member 6 Rotor housing 21 Center hole 25 Stator magnetic pole 34 Powder magnetic core 35, 37 Laminated steel plate body

Claims (4)

A stator having a coil for exciting each stator magnetic pole arranged in the circumferential direction on one end face in the axial direction to N pole, and each stator magnetic pole arranged in the circumferential direction on the other end face in the axial direction to S pole;
A rotor disposed on both sides of the stator so as to face the stator, and a plurality of rotor magnetic poles disposed in the circumferential direction;
An axial gap motor provided with a magnetic path forming member that forms a magnetic path between the rotors through the center hole of the stator,
Each of the rotors includes a dust core disposed in the circumferential direction as each rotor magnetic pole, and a laminated steel sheet body that forms a magnetic path between the dust cores.
The laminated steel sheet body is characterized in that a part of the periphery of each dust core is cut out in a gap shape, and a part of the peripheral surface of each dust core is exposed from the laminated steel sheet body. Axial gap motor. The axial gap motor according to claim 1,
An axial gap motor characterized in that the radially outer portion of each of the dust cores of both rotors is connected to the radially outer portion of the adjacent dust core via the laminated steel sheet body. The axial gap motor according to claim 1 or 2,
An axial gap motor, wherein at least radially inner ends of the dust cores of the rotors protrude radially inward from radially inner ends of the opposing stator magnetic poles. In the axial gap motor in any one of Claims 1-3,
The rotors each include a rotor housing that holds the laminated steel plate body and the dust cores in a lid shape, and the laminated steel plate and the rotor housing have gaps in respective peripheral portions of the dust cores. A characteristic axial gap motor.

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