JP2006166626A - Rotor structure for axial gap type dynamo-electric machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotor structure for axial gap type dynamo-electric machine which can improve the torque as a dynamo-electric machine by sufficiently utilizing reluctance torque, avoiding a reluctance loop as much as possible without breaking it. <P>SOLUTION: In the rotor structure for an axial gap type dynamo-electric machine comprising a rotor 3 which is provided with a plurality of permanent magnets 1 at intervals in its circumferential direction at a disk-like rotor core 2 consisting of a magnetic substance, stators 7 which are counterposed, along the axis of the rotor 3, to the rotor 3 and are constituted by arranging, in its circumferential direction, a plurality of stator cores 5 with coils 4 wound, and a case 10 which fixes the stators 7 and supports the rotor 7 rotatably, the angle of each permanent magnet 1, which is interposed in a position where it interrupts the magnetic flux generated by the stator core 5, which curves while bulging in the circumferential direction of the above rotor 3 and axially crosses the above rotor core 2 in the case of driving the dynamo-electric machine by exciting the above coil 4, is chamfered. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

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

  In general, in a synchronous rotating electrical machine that uses a permanent magnet for the rotor, a magnetic material is placed between adjacent permanent magnets in addition to using the magnet torque generated by attracting and repelling the rotating magnetic field generated by the stator. In the circumferential direction of the rotor, portions having a small magnetic resistance and portions having a large magnetic resistance are alternately provided so that the rotor has a magnetic saliency, and the self-inductance and mutual inductance of the coils constituting the stator are reduced. By changing the magnetic energy stored in the gap between the rotor and the stator to mechanical energy, the so-called reluctance torque is generated to improve the torque of the rotating electrical machine. ing. The reluctance torque can be increased as the difference in the magnetic resistance between the portion with a large magnetic resistance and the portion with a small magnetic resistance (hereinafter referred to as a difference in magnetic resistance) increases in the circumferential direction of the rotor.

  The same applies to an axial gap type rotating electric machine. For example, as shown in Patent Document 1, as shown in FIG. 1, an axial gap type rotating machine having two rotors opposed to each other in the central axis direction as shown in FIG. As shown in FIG. 7, in a rotor applied to an electric machine, a plurality of fan-shaped permanent magnets 51 are inserted into fan-shaped holes that match the permanent magnets 51 provided on a disk-shaped rotor core 52 made of a magnetic material. The rotor core 52 and the permanent magnet 51 are provided with a rotor ring 53 made of a nonmagnetic material.

FIG. 8 is a cross-sectional view showing the OX, OY, and AB cross sections of the rotor shown in FIG. 7, but in the OX cross section shown in FIG. 8 (a), the rotor core 52 is provided through the rotor. In the OY cross section shown in FIG. 8 (a), fan-shaped holes that match the permanent magnet 51 described above are provided on the front and back sides, and the holes are formed on both sides of the front and back surfaces. A permanent magnet 51 is inserted and joined.
In joining a permanent magnet to a rotor core made of an electromagnetic steel plate or a powdered material, a method such as brazing or an adhesive is used. When the rotor core 13 is formed of a powdered material, by sintering, It is also possible to bond the contained metal powder by diffusion bonding.
JP-A-11-187635

  However, in the rotor structure of the axial gap type rotating electrical machine of the above-described form, when the rotating electrical machine is operated by exciting a coil of a stator (not shown) as shown in part C of FIG. The corner of the permanent magnet 51 is interposed at a position where the magnetic core generated by the stator core (not shown), that is, the reluctance loop L is interrupted by being bent while being swelled in the direction of the central axis. However, since the reluctance loop L is interrupted, the difference in the magnetic resistance in the circumferential direction of the rotor described above becomes small, and the reluctance torque cannot be fully utilized, so that the torque of the rotating electrical machine cannot be improved. Arise.

  In the present invention, the object is to solve the above-mentioned problems, and the object is to avoid breaking the reluctance loop as much as possible, and to fully utilize the reluctance torque, so that the torque as a rotating electrical machine can be obtained. It is an object of the present invention to provide a rotor structure for an axial gap type rotating electrical machine that can improve the above.

A rotor structure of an axial gap type rotating electrical machine according to claim 1 includes a rotor in which a plurality of permanent magnets are provided on a disk-shaped rotor core made of a magnetic material at intervals in the circumferential direction, and a rotor along a central axis of the rotor. Of an axial gap type rotating electrical machine comprising a stator having a plurality of stator cores wound around each other and arranged in the circumferential direction, and a case for fixing the stator and rotatably supporting the rotor. In the rotor structure,
When the rotating electrical machine is operated by exciting the coil, the corners of the permanent magnets are interposed at positions that block the magnetic flux generated by the stator core that is curved while expanding in the circumferential direction of the rotor and crosses the rotor core in the central axis direction. It is characterized by chamfering the part.

  According to this, since it is possible to prevent the reluctance loop from being interrupted by the permanent magnet, the reluctance loop can easily pass through the rotor core, and the difference in the magnetic resistance in the circumferential direction of the rotor is increased. Torque can be used more effectively, and thus the torque of the rotating electrical machine can be further increased.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic sectional view of an axial gap type rotating electrical machine showing an embodiment of an axial gap type rotating electrical machine according to the present invention, and FIG. 2 is an embodiment of a rotor structure of the axial gap type rotating electrical machine according to the present invention. It is a partial arrow line view which shows the rotor of an axial gap type rotary electric machine which shows a form seeing from a center axis direction. FIG. 3 is a partial cross-sectional view showing an embodiment of a rotor structure of an axial gap type rotating electrical machine according to the present invention. 3A shows the OX and OY cross sections of FIG. 2, and FIG. 3B shows the AB cross section of FIG.

As shown in FIGS. 1 and 2, the rotor structure of this axial gap type rotating electrical machine has a fan shape in which a plurality of pairs of fan-shaped permanent magnets 1 are provided on both front and back surfaces of a disk-shaped rotor core 2 made of a magnetic material. And a plurality of stator cores 5 each having a coil 4 wound around the rotor 3 and disposed opposite to the rotor 3 along the central axis of the rotor 3. Is fixed to the back core 6 in the circumferential direction, the stator 7 is fixed via the back core 6, and the rotor 3 is connected to a rotating shaft 8 that forms part of the rotor 3. In the rotor structure of an axial gap type rotating electrical machine comprising a case 10 that is rotatably supported via a bearing 9,
When the rotating electrical machine is operated by exciting the coil 4, as shown in FIG. 3 (b), the stator core is curved while expanding in the circumferential direction of the rotor 3 and crosses the rotor core 2 in the central axis direction. The corners of the permanent magnet 1 interposed at a position where the generated magnetic flux, that is, the reluctance loop L is interrupted are chamfered, and the rotor core 2 is interposed at the chamfered portion. (Equivalent to Claim 1) Here, the corner is chamfered into a C shape. (Equivalent to claim 2)

Here, chamfering the corner includes not only chamfering the molded permanent magnet by machining, but also molding the permanent magnet so as to have a chamfered shape in advance. As shown in FIG. 3 (b), the chamfered shape refers to a shape that is linearly inclined with respect to the circumferential direction and the central axis direction of the rotor.
In addition, the reluctance loop L shown in FIG. 3B is shown as an example that swells to the right, but a reluctance loop that swells to the left is also generated, so the side of the permanent magnet 1 facing the stator is also generated. The opposite side, that is, the circumferential side on the back side is chamfered.

  Further, FIG. 3B shows, as an example, the AB cross section located in the radial center in the circumferential cross section of FIG. 2, but the reluctance loop L extends from the innermost circumference side of the rotor core 2 to the outermost circumference. In order to cross across the side, it is necessary to chamfer the corners located on both sides in the circumferential direction on the back side of the permanent magnet 1 in any circumferential section from the innermost circumferential side to the outermost circumferential side. Needless to say. The same applies to FIG. 4B and FIG. 5B described below.

According to the configuration corresponding to the first aspect, the reluctance loop L can be prevented from being blocked by the permanent magnet 1, so that the reluctance loop L can easily pass through the rotor core 2, and the circumferential direction of the rotor 3. Thus, the reluctance torque can be used more effectively by increasing the difference in magnetic resistance, and thus the torque as the rotating electrical machine can be further increased.
According to the configuration corresponding to the second aspect, the corners of the permanent magnet 1 are chamfered in a general C shape, that is, a straight line as shown in FIG. Can be easily obtained.

  In the axial gap type rotating electrical machine of the form shown in FIG. 1, an outer rotor ring 11 is provided on the outer peripheral side of the plurality of fan-shaped permanent magnets 1 and the disk-shaped rotor core 2 constituting the rotor 3. The outer rotor ring 11 supports the centrifugal force acting on the permanent magnet 1 and increases the rigidity of the rotor 3 to enable high rotation. Further, an inner rotor ring 12 is provided on the inner peripheral side of the disk-shaped rotor core 2 to connect the disk-shaped rotor core 2 to the rotating shaft 8. Further, a pair of stators 7 are provided so as to face each other with the rotor 3 interposed therebetween, and a cooling path 13 is provided in the case 10, and the coolant is circulated through the cooling path 13, thereby causing a loss of the stator core 5 and the coil 4. Absorb heat and cool. Further, an encoder 14 for detecting the rotation amount and position of the rotor 3 is provided at the end of the rotating shaft 8.

FIG. 4 is a partial cross-sectional view showing another embodiment of the rotor structure of the axial gap type rotating electrical machine according to the present invention. 4A shows the OX and OY cross sections of FIG. 2, and FIG. 4B shows the AB cross section of FIG.
Since the basic structure of the rotating electrical machine and the rotor structure is the same as that shown in FIGS. 1 to 3, only the differences will be described.
In FIG. 3, the back side of the permanent magnet 1 is chamfered in a linear shape, that is, in a C shape, but in FIG. 4, it is chamfered in an R shape. (Equivalent to claim 3)
Here, the R shape means that the chamfered shape forms an arc shape having a center inside the permanent magnet 1 as shown in FIG.

  Also by this, like the rotor structure shown in FIG. 3, the permanent magnet 1 blocks the reluctance loop L, and the permanent magnet 1 chamfers the reluctance loop L by the permanent magnet 1 to chamfer the reluctance loop L. Since the interruption can be avoided, the reluctance loop L can easily pass through the rotor core 2, the difference in the magnetic resistance in the circumferential direction of the rotor 3 is increased, and the reluctance torque is used more effectively. Thus, the torque of the rotating electrical machine can be further increased.

FIG. 5 is a partial cross-sectional view showing another embodiment of the rotor structure of the axial gap type rotating electrical machine according to the present invention. 5A shows the OX and OY cross sections of FIG. 2, and FIG. 5B shows the AB cross section of FIG.
Since the basic structure of the rotating electrical machine and the rotor structure is the same as that shown in FIGS. 1 to 3, only the differences will be described.
Since the basic structure of the rotating electrical machine and the rotor structure is the same as that shown in FIGS. 1 to 3, only the differences will be described.
In FIG. 3, the back side of the permanent magnet 1 is chamfered in a linear shape, that is, in a C shape, but in FIG. 5, it is chamfered in an inverted R shape. (Equivalent to claim 4)
Here, the inverted R shape means that the chamfered shape forms an arc having a center outside the permanent magnet 1 as shown in FIG.

  Also by this, like the rotor structure shown in FIG. 3, the reluctance loop L is blocked by the permanent magnet 1 by chamfering the permanent magnet 1 into a general inverted R shape. Since the reluctance loop L can easily pass through the rotor core 2 and the difference in the magnetic resistance in the circumferential direction of the rotor 3 is increased, the reluctance torque can be used more effectively. As a result, the torque of the rotating electrical machine can be further increased.

FIG. 6 is a circumferential cross-sectional view showing still another embodiment of the rotor structure of the axial gap type rotating electrical machine according to the present invention. The circumferential cross section here should just contain the permanent magnet, and may be any circumferential cross section from the innermost circumference side to the outermost circumference side of the permanent magnet.
This rotor structure is a structure that is applied to an axial gap type rotating electric machine that is configured with one rotor 21 facing one rotor 21, and the reluctance loop L is the center of the rotor as shown in FIG. Inclined with respect to the axial direction, enters from one surface of the rotor core 23 constituting the rotor 21, and curves in the middle of adjacent permanent magnets 24 arranged at equal intervals in the circumferential direction with its direction reversed. Then, it exits from one surface of the rotor core 23 and returns to the stator 22.

For this reason, unlike the rotor structure of an axial gap type rotating electrical machine in which two stators are opposed to one rotor as shown in FIGS. 1 to 5, the permanent structure interposed at a position where the reluctance loop L is interrupted. The corners of the magnet 24 are not the back side but the sides facing the stator 22, that is, the corners on both sides in the circumferential direction on the gap side.
Here, the corner of the permanent magnet 24 on the gap side is chamfered in a C shape, and the rotor core 23 is provided so as to increase its volume so as to cover the chamfered portion (corresponding to claim 2).

  This also prevents the reluctance loop L from being interrupted by the permanent magnet 24 by chamfering the reluctance loop L from the permanent magnet 24 and chamfering the permanent magnet 24 into a general C shape. Therefore, the reluctance loop L can easily pass through the rotor core 23, the difference in the magnetic resistance in the circumferential direction of the rotor 21 can be increased, and the reluctance torque can be used more effectively. Can be further enhanced.

Here, in the rotor structure shown in FIGS. 1 to 6, the rotor core is configured by laminating electromagnetic steel plates. (Equivalent to claim 5) In this case, magnetic steel sheets punched by pressing or the like are wound and stacked in the radial direction so as to allow insertion of a chamfered permanent magnet in advance, thereby forming a rotor core.
Thereby, the rotor structure of the axial gap type rotating electrical machine as described above can be realized by a general electromagnetic steel sheet.

Or in the rotor structure shown in FIGS. 1-6, a rotor core is comprised with a compacting material. (Equivalent to claim 6)
Note that the dust material is a material obtained by mixing and solidifying magnetic powder such as iron powder and an insulator such as resin.
According to this, compared to forming the rotor core with magnetic steel sheets, the rotor core can be formed more easily due to the high degree of freedom of the shape unique to the compacted material, and in turn chamfering the permanent magnet. The degree of freedom in shape can be increased.

  In the axial gap type rotating electrical machine shown in FIG. 1, when the coil 4 is excited by an inverter (not shown), a rotating magnetic field is formed in the circumferential direction of the stator 7, and a plurality of permanent magnets 1 having different polarities are embedded in the circumferential direction. The rotor 3 is attracted and repelled by the rotating magnetic field and rotates at a synchronous speed with the rotating magnetic field.

  In addition, this invention is not limited only to the said embodiment, Many deformation | transformation or a change is possible.

  The present invention is suitable for use in a rotor structure of an axial gap type rotating electrical machine, and can effectively use the reluctance torque to improve the torque as the rotating electrical machine.

1 is a schematic cross-sectional view showing an embodiment of an axial gap type rotating electrical machine according to the present invention. 1 is a schematic arrow view showing an embodiment of a rotor structure of an axial gap type rotating electrical machine according to the present invention. 1 is a schematic cross-sectional view showing an embodiment of a rotor structure of an axial gap type rotating electrical machine according to the present invention. It is a schematic sectional drawing which shows other embodiment of the rotor structure of the axial gap type rotary electric machine which concerns on this invention. It is a schematic sectional drawing which shows other embodiment of the rotor structure of the axial gap type rotary electric machine which concerns on this invention. It is a schematic sectional drawing which shows other embodiment of the rotor structure of the axial gap type rotary electric machine which concerns on this invention. It is a schematic arrow view which shows the rotor structure of the conventional axial gap type rotary electric machine. It is a schematic sectional drawing which shows the rotor structure of the conventional axial gap type rotary electric machine.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Permanent magnet 2 Rotor core 3 Rotor 4 Coil 5 Stator core 6 Stator back core 7 Stator 8 Rotating shaft 9 Bearing 10 Case 11 Outer rotor ring 12 Inner rotor ring 13 Cooling path 14 Encoder 21 Rotor 22 Stator 23 Rotor core 24 Permanent magnet 51 Permanent magnet 52 Rotor core 53 Rotor ring

Claims (6)

A rotor in which a plurality of permanent magnets are provided on a disk-shaped rotor core made of a magnetic material at intervals in the circumferential direction, and a plurality of stator cores that are disposed so as to face the rotor along the central axis of the rotor and are wound with coils. In the rotor structure of an axial gap type rotating electrical machine comprising a stator that is arranged in the circumferential direction and a case that fixes the stator and supports the rotor rotatably,
When the rotating electrical machine is operated by exciting the coil, the corners of the permanent magnets are interposed at positions that block the magnetic flux generated by the stator core that is curved while expanding in the circumferential direction of the rotor and crosses the rotor core in the central axis direction. A rotor structure of an axial gap type rotating electrical machine with chamfered portions. The rotor structure of an axial gap type rotating electrical machine according to claim 1, wherein the corner portion is chamfered into a C shape. The rotor structure of an axial gap type rotating electrical machine according to claim 1, wherein the corner portion is chamfered into an R shape. The rotor structure of an axial gap type rotating electrical machine according to claim 1, wherein the corner portion is chamfered into an inverted R shape. The rotor structure of an axial gap type rotating electrical machine according to any one of claims 1 to 4, wherein the rotor core is configured by laminating electromagnetic steel plates. The rotor structure of an axial gap type rotating electrical machine according to any one of claims 1 to 4, wherein the rotor core is made of a dust material.

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