JP2006304539A - Rotor structure of axial gap rotating electric machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide the rotor structure of an axial gap rotating electric machine in which the holding strength of a rotor to a permanent magnet can be enhanced and a rotation limit as a rotating electric machine can be elevated. <P>SOLUTION: A plurality of substantially sectoral columnar permanent magnets 11 are inserted into a plurality of substantially sectoral holes 13 formed in the circumferential direction of a disc-like member 12. A taper profile or a step profile, a taper profile 11a in this case, is provided at the circumferential end on the gap side of the permanent magnet 11. A plurality of pairs of holding members 14 each having a taper profile or a step profile 14a fitting to the above-mentioned taper profile or the step profile are bonded to the disc-like member 12 located between the adjacent permanent magnets 11. A pair of shaft securing portions 15 are bonded to the inner circumferential side of the permanent magnet 11 in the disc-like member 12, and a pair of outer rings 16 are bonded to the outer circumferential side of the permanent magnet 11 in the disc-like member 12. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a rotor structure of an axial gap type rotating electrical machine in which a stator and a rotor are arranged to face each other along a rotation axis.

  A rotating electrical machine having a permanent magnet on a rotor is used in many automobiles or industrial machines for reasons such as low loss, high efficiency, and high output. In particular, since the axial gap type rotating electrical machine in which the stator and the disk-shaped rotor are arranged so as to face each other along the rotation axis can reduce the thickness in the rotation axis direction, Patent Document 1 and Patent Document As described in FIG. 2, it is more frequently used when there is a layout restriction.

In the rotor structure of the axial gap type rotating electrical machine described in Patent Document 1, in fixing the permanent magnet to the rotor, the resin adhesive on the back side of the permanent magnet is devoured to hold the permanent magnet in the radial direction and the circumferential direction. In the rotor structure of the axial gap type rotating electrical machine described in Patent Document 2, the strength is increased, and a plurality of holes are formed in a disk-like member made of a non-magnetic material in the axial direction so that the divided permanent magnet is axially The holding strength in the radial direction and the circumferential direction with respect to the permanent magnet is increased.
JP 2004-80898 A JP-A-6-38418

  However, in the axial gap type rotating electrical machine, a large force acts on the permanent magnet of the rotor in the circumferential direction by the rotating magnetic field of the stator, and a large force acts on the rotor in the radial direction by the centrifugal force. Since a large force is also applied in the axial direction by the magnetic field, in the rotor structure of the axial gap type rotating electrical machine having such a configuration, when a large axial force is applied to the permanent magnet of the rotor, the permanent magnet is sufficiently retained. There was a problem that the strength could not be maintained and it was difficult to increase the rotation limit of the rotating electrical machine.

  The object of the present invention is to solve the above-described problems, and the object is to increase the axial holding strength of the rotor with respect to the permanent magnet, and to increase the rotation limit of the rotating electrical machine. Another object of the present invention is to provide a rotor structure for an axial gap type rotating electrical machine.

  In the rotor structure of the axial gap type rotating electrical machine according to the present invention, a plurality of permanent magnets are inserted into a plurality of holes provided side by side in the circumferential direction of the disk-shaped member, and tapered to the circumferential end on the gap side of the permanent magnet. A shape or step shape is provided, and a plurality of pairs of holding members having a taper shape or a step shape fitting to the taper shape or the step shape are joined to the disk-like member located between adjacent permanent magnets. The pair of shaft fixing portions are joined to the inner peripheral side of the permanent magnet of the disk-shaped member, and the pair of outer rings are joined to the outer peripheral side of the permanent magnet of the disk-shaped member. Features.

  According to this, with respect to the taper shape or step shape provided at the circumferential end of the gap surface of the permanent magnet, it has a taper shape or step shape that fits into the taper shape or step shape from the outside in the axial direction. Since the holding member can be joined to the disk-shaped member after covering the holding member, the permanent magnet is firmly held in the axial direction by the holding member, and the axial direction of the rotor with respect to the permanent magnet is increased. Holding strength can be increased.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic cross-sectional view showing an embodiment of a general axial gap type rotating electrical machine.
In this axial gap type rotating electrical machine, a stator 3 formed by winding a coil 2 around a core 1 and a rotor 4 are arranged to face each other along a rotation axis. The rotor 4 includes a plurality of permanent magnets 5. Are arranged at equal intervals in the circumferential direction, and a shaft 6 is provided on the inner circumferential side thereof. The shaft 6 is rotatably supported by a case 8 via a bearing 7. Further, a cooling path 9 is provided in the case 8 to circulate a cooling liquid for absorbing and cooling heat generated by the loss of the stator 3. Furthermore, an encoder 10 for detecting the rotation amount and position of the rotor 4 is provided at the end of the rotating shaft 6.

  In the axial gap type rotating electrical machine shown in FIG. 1, when the coil 2 is excited by an inverter (not shown), a rotating magnetic field is formed in the circumferential direction of the stator 3, and a plurality of permanent magnets 5 having different polarities alternately are embedded in the circumferential direction. The disk-shaped rotor 4 is attracted and repelled by the rotating magnetic field generated by the stator 3 to generate magnet torque, and also generates reluctance torque due to the presence of the magnetic material constituting the rotor 4, which is used as power. The rotor 4 rotates at a synchronous speed with the rotating magnetic field.

FIG. 2 is a schematic diagram showing in detail the rotor structure of the axial gap type rotating electrical machine according to the present invention. FIG. 2 (a) shows a state before assembly, and FIG. 2 (b) shows a state after assembly.
In the rotor structure of this axial gap type rotating electrical machine, a plurality of substantially sector-shaped columnar permanent magnets 11 are inserted into a plurality of substantially sector-shaped holes 13 arranged side by side in the circumferential direction of the disk-shaped member 12, and the permanent magnets 11. A taper shape or a step shape, here a taper shape 11a, is provided at the circumferential end on the gap side of this, and a taper that fits in the taper shape or the step shape to the disk-like member 12 located between the adjacent permanent magnets 11 is provided. A plurality of pairs of holding members 14 having a shape or step shape, here a tapered shape 14a, are provided by being joined from the outside in the axial direction, and a pair of shaft fixing portions 15 on the inner peripheral side of the permanent magnet 11 of the disk-like member 12. Are joined from the outside in the axial direction, and a pair of outer rings 16 are joined from the outside in the axial direction to the outer peripheral side of the permanent magnet 11 of the disk-like member 12. (Equivalent to claim 1)
In addition, a hole for fitting a shaft (not shown) is provided on the inner peripheral side of the disk-shaped member 12 and the pair of shaft fixing portions 15, and is configured by stacking electromagnetic steel plates or integrated with a soft magnetic dust material. Molded and configured.

According to this, the taper shape or step shape provided at the circumferential end of the gap surface of the permanent magnet 11, here the taper shape that fits into the taper shape or step shape from the outside in the axial direction with respect to the taper shape 11 a. Alternatively, since the holding member 14 can be joined to the disk-shaped member 12 after covering the holding member 14 having a stepped shape, here a tapered shape 14a, the permanent magnet 11 is pivoted by the holding member 14. The holding strength in the axial direction with respect to the permanent magnet 11 of the rotor 4 can be increased by firmly holding in the direction. Furthermore, the magnet and the holding member 14 are deformed in the radial direction by receiving a centrifugal force at a high rotation speed. However, the magnet and the holding member 14 having different materials are different in durability against deformation and are different in the way of receiving the centrifugal force. . By not bonding the holding member 14 and the magnet with an adhesive or the like, it is possible to prevent the deformation in the radial direction from affecting each other due to centrifugal force, and particularly the cracking of the holding member 14 that is vulnerable to elastic deformation occurs. Can be prevented. Even if the holding member 14 is not bonded, there is no problem because the holding member 14 is fitted by the tapered shape.
In order to hold the permanent magnet 11 in the axial direction by the holding member 14, it is necessary to make the thickness of the disk-like member 12 smaller than the thickness of the permanent magnet.

  Of course, the taper shape or step shape 11a and the taper shape or step shape 14a fitted to the taper shape or step shape 14a cover the permanent magnet 11 with the holding member 14 covering the circumferential end of the gap surface from the outside in the axial direction. As long as the holding force in the direction is applied, the shape is not limited to the tapered shape or the step shape, and other forms are also possible.

  FIG. 3 is a schematic view showing a permanent magnet having a rotor structure of an axial gap type rotating electrical machine according to the present invention. 3A shows a view of the permanent magnet as viewed from the gap side of the rotor, FIG. 3B shows a view of the permanent magnet as viewed from the circumferential direction of the rotor, and FIG. It is a figure which shows the AA cross section in a).

As shown in FIG. 3A, the permanent magnet 11 is formed in a substantially fan shape when viewed from the gap side of the rotor, and the circumferential end on the outer peripheral side of the hole 13 of the disk-shaped member 12 described above. Corresponding to the shape of the portion having an R shape for securing the strength, the circumferential end on the outer peripheral side is chamfered into a C shape. Further, the permanent magnet 11 is configured by laminating thin plate-like permanent magnets in the radial direction and bonding them with a resin or the like.
Furthermore, as shown to Fig.3 (a), the taper shape 11a is provided in the circumferential direction both ends by the side of a gap.

  Therefore, when the permanent magnet 11 is viewed from the circumferential direction, as shown in FIG. 3B, tapered shapes 11a are formed on both sides thereof, and the shape in the cross section AA perpendicular to the radial direction shown in FIG. , Make a rectangle with chamfered corners.

  FIG. 4 is a schematic view showing a holding member of a rotor structure of an axial gap type rotating electrical machine according to the present invention. 4A shows a view of the holding member as seen from the radial direction of the rotor, FIG. 4B shows a view of the holding member as seen from the gap side of the rotor, and FIG. 4C shows the holding member as the rotor. FIG. 4D is a perspective view showing the gap side of the holding member as seen from the inner circumference side.

As shown in FIG. 4, the holding member 14 is formed with a tapered shape 14 a that fits to the tapered shape 11 a of the permanent magnet 11 described above at the opposite circumferential end when viewed from the gap side. The holding strength in the axial direction of the permanent magnet 11 can be increased by the holding member 14 by fitting the tapered shape 14a to the tapered shape 11a described above.
Further, an additional tapered shape 14b described later is provided on the inner peripheral end of the holding member 14 on the gap side.

Here, the holding member 14 is configured by laminating electromagnetic steel plates. (Equivalent to claim 2)
According to this, eddy current loss generated inside the holding member 14 can be reduced with a simple configuration, and the holding member 14 is made of a magnetic material, and the holding member 14 having a low magnetic resistance and a high magnetic resistance are used. Due to the fact that the permanent magnets are alternately provided in the circumferential direction, reluctance torque can be obtained.

Alternatively, the holding member 14 can be made of a soft magnetic powder material. (Equivalent to claim 3)
This also makes it possible to reduce the eddy current loss generated inside the holding member 14 with a simple configuration, and to use the holding member 14 as a magnetic body, to make the holding member 14 with a low magnetic resistance, and to make a permanent with a high magnetic resistance. Reluctance torque can be obtained due to the magnets being alternately provided in the circumferential direction. In addition, as compared with the case where the holding member 14 is configured by a laminated core in which electromagnetic steel plates are laminated, the degree of freedom of shape of the holding member 14 can be increased and the manufacturing cost can be suppressed.

FIG. 5 is a schematic view showing a disk-shaped member of the rotor structure of the axial gap type rotating electric machine according to the present invention as seen from the direction of the central axis of the rotor.
As shown in FIG. 5, the disk-shaped member 12 is provided with a plurality of fan-shaped holes in the circumferential direction, which is the same number as the plurality of fan-shaped permanent magnets described above. By providing holes at equal intervals in the circumferential direction as described above, the portion located between the holes increases the radial strength of the disk-shaped member. As a result, the radial holding strength of the disk-shaped member 12 with respect to the permanent magnet 11 can be increased.

FIG. 6 is a schematic diagram showing the outer ring of the rotor structure of the axial gap type rotating electrical machine according to the present invention as seen from the direction of the central axis of the rotor.
As shown in FIG. 6, the outer ring 16 is formed in an annular shape, and as described above, the outer circumferential surface of the outer ring 16 is a disk-shaped member so as to be joined to the outer circumferential side of the permanent magnet of the disk-shaped member (not shown). An annular groove that encloses the outer peripheral side of the disk-shaped member is formed on the inner peripheral surface thereof.

FIG. 7 is a schematic cross-sectional view showing the rotor structure of the axial gap type rotating electrical machine according to the present invention in a cross section including the central axis.
As described above, a plurality of substantially sector-shaped columnar permanent magnets 11 are inserted through a plurality of substantially sector-shaped holes 13 arranged side by side in the circumferential direction of the disk-shaped member 12, and the circumferential direction of the permanent magnet 11 on the gap side. A tapered shape or stepped shape, here a tapered shape 11a, is provided, and a tapered shape 14a (or a stepped shape) is fitted to the disk-shaped member 12 positioned between the adjacent permanent magnets 11 (or the stepped shape). Alternatively, a plurality of pairs of holding members 14 having a step shape) are joined from the outside in the axial direction, and a pair of shaft fixing portions 15 are joined from the outside in the axial direction to the inner peripheral side of the permanent magnet 11 of the disk-like member 12. A pair of outer rings 16 are joined to the outer peripheral side of the permanent magnet 11 of the disk-shaped member 12 from the outside in the axial direction. In addition, the shaft 6 is fitted to the inner peripheral side of the disk-shaped member 12 and the pair of shaft fixing portions 15 via a key.

Furthermore, an additional tapered shape 14b (or an additional step shape) is provided on at least one of the inner peripheral side end and the outer peripheral side end on the gap side of the holding member 14, here the inner peripheral side end, and the shaft fixing portion and the outer ring, The shaft fixing portion 15 is provided with an additional taper shape 15b (or additional step shape) that fits into the additional taper shape (or additional step shape). (Equivalent to claim 4)
In addition, what is called an additional taper shape or an additional step shape here is for distinguishing from the taper shape or step shape corresponding to Claim 1.

  According to this, the additional taper shape 14b of the holding member 14 is covered with the additional taper shape 15b of the shaft fixing portion 15 from the outside in the axial direction, so that the holding strength in the axial direction of the holding member 14 can be increased. Further, the holding strength in the axial direction of the permanent magnet 11 by the holding member 14 can also be increased. This effect is the same whether the additional taper shape is provided at the outer peripheral end or both the inner peripheral end and the outer peripheral end.

FIG. 8 is a schematic view showing the rotor structure of the axial gap type rotating electrical machine according to the present invention as seen from the central axis direction.
As described above, a plurality of substantially sector-shaped columnar permanent magnets 11 are inserted through a plurality of substantially sector-shaped holes 13 arranged side by side in the circumferential direction of the disk-shaped member 12, and the circumferential direction of the permanent magnet 11 on the gap side. A taper shape or a step shape, here a taper shape 11a, is provided at the end, and a plurality of pairs of holding members having a taper shape 14a fitted to the taper shape 11a on the disk-like member 12 positioned between the adjacent permanent magnets 11 The member 14 is joined and provided from the outside in the axial direction, and a pair of shaft fixing portions 15 are joined to the inner periphery side of the permanent magnet 11 of the disk-like member 12 by bolting from the outside in the axial direction. A pair of outer rings 16 are provided on the outer peripheral side of the permanent magnet 11 of the shaped member 12 by bonding with an adhesive from the outside in the axial direction.

  In addition, the shaft 6 is fitted to the inner peripheral side of the disk-shaped member 12 and the pair of shaft fixing portions 15 via a key. A gap formed between the substantially fan-shaped hole 13 and the permanent magnet 11 is filled with resin or the like.

  Further, an additional tapered shape 14b is provided on at least one of the inner peripheral side end and the outer peripheral side end on the gap side of the holding member 14, here the inner peripheral end, and the shaft fixing part and the outer ring, here the shaft fixing part 15 are provided. An additional taper shape 15b fitted to the additional taper shape 14b is provided.

For this reason, as shown in FIG. 8, the circumferential end of the permanent magnet 11 and the circumferential end of the holding member 14 overlap in the circumferential direction by the width of the tapered shape 11a. Thereby, the holding strength in the axial direction of the permanent magnet 11 can be increased.
Further, as shown in FIG. 8, the inner peripheral end of the holding member 14 overlaps the outer peripheral end of the shaft fixing portion 15 in the radial direction by the width of the additional tapered shape 14b. Thereby, the holding strength in the axial direction of the holding member 14 by the shaft fixing portion 15 can be increased, and consequently the holding strength in the axial direction of the holding member 15 with respect to the permanent magnet 11 can be increased.

In addition, this invention is not limited only to the said embodiment, Many deformation | transformation or a change is possible.
For example, FIG. 1 shows, as an example, an axial gap type rotating electric machine in the form of one rotor and two stators, but the rotor structure according to the present invention is also applied to an axial gap type rotating electric machine in the form of one rotor and two stators. Is possible.

  The present invention is suitable for use in a rotor of an axial gap type rotating electrical machine. A large force acts on the permanent magnet of the rotor in the circumferential direction by the rotating magnetic field of the stator, and a large force in the radial direction by the centrifugal force. In the axial gap type rotating electrical machine in which a large force is also applied in the axial direction by the rotating magnetic field of the stator, the holding strength in the axial direction of the permanent magnet of the rotor can be increased and the rotation limit can be increased. Is.

It is a schematic cross section which shows the structure of a general axial gap type rotary electric machine. It is a mimetic diagram showing one embodiment of a rotor structure of an axial gap type rotating electrical machine concerning the present invention. It is a schematic diagram which shows one Embodiment of the permanent magnet of the rotor structure of the axial gap type rotary electric machine which concerns on this invention. It is a schematic diagram which shows one Embodiment of the holding member of the rotor structure of the axial gap type rotary electric machine which concerns on this invention. It is a schematic diagram which shows one Embodiment of the disk-shaped member of the rotor structure of the axial gap type rotary electric machine which concerns on this invention. It is a schematic diagram which shows one Embodiment of the outer ring | wheel of the rotor structure of the axial gap type rotary electric machine which concerns on this invention. It is a schematic cross section which shows the rotor structure of the axial gap type rotary electric machine which concerns on this invention in the cross section containing a central axis. It is a schematic diagram which shows the rotor structure of the axial gap type rotary electric machine which concerns on this invention seeing from the center axis line direction.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Core 2 Coil 3 Stator 4 Rotor 5 Permanent magnet 6 Shaft 7 Bearing 8 Case 9 Cooling path 10 Encoder 11 Permanent magnet 11a Taper shape 12 Disk-shaped member 13 Hole 14 Holding member 14a Taper shape 14b Additional taper shape 15 Shaft fixing part 15b Additional taper shape 16 outer ring

Claims (4)

  A plurality of permanent magnets are inserted into a plurality of holes arranged side by side in the circumferential direction of the disk-shaped member, and a tapered shape or a step shape is provided at the circumferential end on the gap side of the permanent magnet, and between the adjacent permanent magnets. A plurality of pairs of holding members having a taper shape or a step shape that fits into the taper shape or step shape is joined to the disk-shaped member that is positioned, and the inner periphery side of the permanent magnet of the disk shape member A rotor structure for an axial gap type rotating electrical machine, wherein a pair of shaft fixing portions are joined to each other and a pair of outer rings are joined to the outer peripheral side of the permanent magnet of the disk-like member.   The rotor structure of an axial gap type rotating electrical machine according to claim 1, wherein the holding member is configured by laminating electromagnetic steel plates.   The rotor structure of an axial gap type rotating electrical machine according to claim 1, wherein the holding member is made of a soft magnetic powder material.   An additional tapered shape or an additional step shape is provided on at least one of the inner peripheral side end and the outer peripheral side end of the holding member on the gap side, and the shaft fixing portion and the outer ring are fitted into the additional tapered shape or the additional step shape. The stator structure of an axial gap type rotating electric machine according to claim 1, wherein an additional taper shape or an additional step shape is provided.

Images