JP2010279185A - Rotor for axial gap type rotary electric machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-efficient and inexpensive rotor for axial gap type rotary electric machines. <P>SOLUTION: The rotor 10 for axial gap type rotary electric machines includes a frame 1 capable of rotating with the axis of rotation as the center, and a plurality of field sections 2 that are arranged around a rotation axis center C of the frame 1 and include a magnetic pole surface on an axial end face. At each field section 2, two permanent magnet pieces 211 including magnetic pole surfaces formed in a right-angled trapezoid or a right angled triangle are arranged so that width W1 at the outer-periphery side of the frame 1 becomes larger than that W2 at the side of the rotation axis center C, and the two permanent magnet pieces 211 are formed by dividing a permanent magnet including a rectangular magnetic pole surface into two equal parts by a parting line inclined to the side. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a rotor for an axial gap type rotating electrical machine.

  An axial gap type rotating electrical machine is a rotating electrical machine including a rotor that is arranged to be rotatable about a rotation axis and a stator that is arranged with a gap in the direction of the rotation axis of the rotor. An axial gap type rotating electrical machine is preferable to rotating electrical machines of other structures in that the structure can be reduced in thickness and the magnetic pole area can be increased to improve the torque density.

  Patent Document 1 below describes that a rare earth sintered magnet formed by a vertical magnetic field press is used as a permanent magnet constituting a field part of a rotor of an axial gap type rotating electrical machine. The vertical magnetic field press is a method of press-molding magnet powder by applying a magnetic field in a direction perpendicular to the press direction, and can reduce disturbance in the orientation of the magnet powder compared to a parallel magnetic field press in which a magnetic field is applied parallel to the press direction. A permanent magnet having excellent magnetic properties can be obtained.

JP 2009-33946 A, paragraph “0019”

  However, the permanent magnet formed by the vertical magnetic field press is formed in a rectangular parallelepiped shape because of applying a magnetic field in a direction perpendicular to the press direction, and the magnetic pole surface is formed in a rectangular shape. Therefore, in an axial gap type rotating electrical machine, in order to maximize the magnetic pole area of the rotor, it is necessary to make the magnetic pole surface of each field part substantially fan-shaped, which has been conventionally obtained by a vertical magnetic field press. When a permanent magnet is used, the rectangular parallelepiped permanent magnet must be cut into a substantially fan shape, and there is a lot of wasted magnetic material such as a broken piece, which has increased the manufacturing cost of the rotor.

  The present invention was made in view of the above-mentioned drawbacks in a conventional axial gap type rotating electrical machine rotor using a permanent magnet molded by a vertical magnetic field press, and there is almost no waste of magnet material. An object of the present invention is to provide an inexpensive and highly efficient rotor for an axial gap type rotating electrical machine.

The present invention relates to an axial gap type rotation including a frame rotatable around a rotation axis, and a plurality of field portions disposed around the rotation axis of the frame and having a magnetic pole surface on an axial end surface. An electric rotor,
Each field part is configured by arranging two permanent magnet pieces having right-angled trapezoidal or right-angled triangular magnetic pole faces so that the width on the outer peripheral side of the frame is larger than the width on the rotation axis side, The two permanent magnet pieces are formed by dividing a permanent magnet having a rectangular magnetic pole surface into two equal parts by a dividing line inclined with respect to the side thereof.

  In the present application, the right trapezoid means a trapezoid having two adjacent internal angles at right angles. Moreover, a rectangle means a rectangle or a square. In addition, minute chamfering and rounding of the corners are arbitrary.

  Further, the present invention is characterized in that an inner permanent magnet piece having a rectangular magnetic pole surface is disposed between the two permanent magnet pieces.

According to another aspect of the present invention, there is provided an axial gap comprising: a frame that is rotatable about a rotation axis; and a plurality of field portions that are disposed around the rotation axis of the frame and have a pole face on an axial end surface. A rotor for a rotary electric machine,
Each of the field portions has two permanent magnet pieces each having a right trapezoid or right triangle pole face, and one inner permanent magnet piece having an isosceles trapezoid pole face disposed between the two permanent magnet pieces; Are arranged side by side so that the width on the outer peripheral side of the frame is larger than the width on the rotation axis side, and the two permanent magnet pieces and the one inner permanent magnet piece have rectangular magnetic pole faces. The permanent magnet is divided by two dividing lines inclined at an equal angle with respect to the side thereof.

According to another aspect of the present invention, there is provided an axial gap comprising: a frame that is rotatable about a rotation axis; and a plurality of field portions that are disposed around the rotation axis of the frame and have a pole face on an axial end surface. A rotor for a rotary electric machine,
Two permanent magnet pieces each having a right trapezoid or right triangle pole face, and two inner permanent magnets having a right trapezoid or right triangle pole face disposed between the two permanent magnet pieces. Are arranged such that the width on the outer peripheral side of the frame is larger than the width on the rotational axis side, and the two permanent magnet pieces are one permanent magnet having a rectangular magnetic pole surface. The two inner permanent magnet pieces are bisected by a dividing line inclined with respect to the side, and the two inner permanent magnet pieces are bisected with a dividing line inclined with respect to the side. It is characterized by being divided.

  Further, the present invention is characterized in that the two permanent magnet pieces are arranged with their hypotenuses facing each other.

  Further, the present invention is characterized in that the lengths of the opposing sides of the permanent magnet piece and the inner permanent magnet piece are substantially the same.

  Further, the present invention is characterized in that a residual magnetic flux density of the inner permanent magnet piece is larger than a residual magnetic flux density of the permanent magnet piece.

  Further, the present invention is characterized in that a coercive force of the inner permanent magnet piece is smaller than a coercive force of the permanent magnet piece.

  Further, the present invention is characterized in that the coercive force of the permanent magnet piece on the reverse side in the rotational direction of the frame is larger than the coercive force of the permanent magnet piece on the forward side in the rotational direction of the frame.

  In addition, the present invention is characterized in that each of the field portions includes a substantially fan-shaped magnetic core superimposed on the permanent magnet piece or the inner permanent magnet piece.

  Moreover, the present invention is characterized in that the permanent magnet is an Nd—Fe—B based sintered magnet.

  The rotor for an axial gap type rotating electrical machine according to the present invention includes two permanent magnet pieces each having a plurality of field portions each having a right trapezoidal or triangular magnetic pole face, and the width on the outer peripheral side of the frame is on the rotational axis side. The two permanent magnet pieces are formed by dividing the permanent magnet having a rectangular magnetic pole surface into two equal parts by a dividing line inclined with respect to the side thereof. Therefore, it is possible to use a permanent magnet excellent in characteristics that are formed by a vertical magnetic field press and form a rectangular parallelepiped shape without any waste, and it is possible to provide an inexpensive and highly efficient rotor for an axial gap type rotating electrical machine. .

  In addition, since each field portion is configured by arranging a plurality of permanent magnet pieces, for example, a plurality of permanent magnet pieces having different characteristics such as residual magnetic flux density and coercive force can be easily combined as necessary. In addition, a more efficient axial gap type rotating electrical machine rotor can be provided.

It is a schematic sectional drawing of the axial gap type rotary electric machine provided with the rotor of this embodiment. It is a perspective view of the decomposition | disassembly state of the rotor of this embodiment. It is a top view of the assembly state of the rotor. It is explanatory drawing which shows the arrangement | sequence state of the several permanent magnet piece of the same rotor. It is explanatory drawing which shows the division | segmentation state of the several permanent magnet piece of the rotor. It is a perspective view of the decomposition | disassembly state of the modification of the rotor which concerns on this invention. It is explanatory drawing which shows the arrangement | sequence state of the several permanent magnet piece and inner permanent magnet piece of the rotor. It is explanatory drawing which shows the division | segmentation state of the several permanent magnet piece of the rotor. It is a figure showing the other modification of the rotor which concerns on this invention, (a) is explanatory drawing which shows the arrangement state of a several permanent magnet piece and an inner side permanent magnet piece, (b) is the division | segmentation state of a some permanent magnet piece It is explanatory drawing which shows. It is a figure showing the further another modification of the rotor which concerns on this invention, (a) is explanatory drawing which shows the arrangement | sequence state of a some permanent magnet piece and an inner side permanent magnet piece, (b) is a some permanent magnet piece and an inner side It is explanatory drawing which shows the division | segmentation state of a permanent magnet piece. It is a figure showing the further another modification of the rotor which concerns on this invention, (a) is explanatory drawing which shows the arrangement | sequence state of several permanent magnet pieces and several inner permanent magnet pieces, (b) is several permanent magnet pieces. It is explanatory drawing which shows each division | segmentation state of a several inner permanent magnet piece. It is explanatory drawing which shows the further another modification of the rotor which concerns on this invention.

  The rotor according to the present invention is used for an axial gap type rotating electrical machine. As shown in the schematic diagram of FIG. 1, the axial gap type rotating electrical machine 100 includes a rotor 10 disposed so as to be rotatable about a rotating shaft 40 (rotating axis C), and both sides of the rotor 10 in the rotating shaft direction. The first stator 20 and the second stator 30 are provided with a predetermined gap therebetween. The first stator 20 includes a back yoke 201, a tooth 202 erected on the back yoke 201, and a coil 203 wound around the tooth 202, and the second stator 30 includes a back yoke 301. Has been. The first stator 20 and the second stator 30 are fixed to a container (not shown), and the rotation shaft 40 penetrates through the rotation shaft 40 in a rotatable manner.

  As shown in FIGS. 1 to 3, the rotor 10 of the present embodiment is fixed to a rotary shaft 40 and is composed of a frame 1 made of a nonmagnetic material that can rotate around a rotary axis C, and a rotary shaft of the frame 1. A plurality of field portions 2 disposed around the core C and having a magnetic pole surface on the axial end surface, and a pressing member 3 that fixes the plurality of field portions 2 to the frame 1 are configured.

  As shown in the exploded perspective view of FIG. 2, the frame 1 projects radially from an inner peripheral portion 12 having a shaft hole 11 into which a rotary shaft 40 (not shown) can be inserted, and an outer surface of the inner peripheral portion 12. Spoke portion 13 and an outer peripheral portion 14 provided at the tip of the spoke portion 13. The outer surface of the inner peripheral portion 12, the side surface of each spoke portion 13, and the inner periphery of the outer peripheral portion 14 There are a total of six field part holding holes 15 partitioned by the side surface.

  As shown in FIG. 2, the field portion 2 is superposed on the permanent magnet portion 21 held in the field portion holding hole 15 of the frame 1 and the permanent magnet portion 21, and the same field portion holding hole 15. And a substantially fan-shaped magnetic core 22 held inside. Here, the magnetic body of the magnetic body core 22 refers to a soft magnetic body such as iron.

  As shown in FIG. 4, the permanent magnet portion 21 includes two permanent magnet pieces 211 and 211 having a right trapezoidal magnetic pole face and a circumferential width W1 on the outer peripheral side (outer peripheral portion 14 side) of the frame 1. Are arranged side by side so as to be larger than the circumferential width W2 on the rotation axis C side (inner peripheral portion 12 side).

  These two permanent magnet pieces 211 and 211 are formed by obliquely dividing an Nd—Fe—B (neodymium, iron, boron) sintered magnet formed into a rectangular parallelepiped shape by a vertical magnetic field press into two equal parts. Yes. That is, as shown in FIG. 5, a permanent magnet M1 having a rectangular magnetic pole surface obtained by vertical magnetic field pressing is divided into two equal parts by a dividing line V1 inclined at an angle θ1 with respect to the side of the permanent magnet M1. Two permanent magnet pieces 211 and 211 having the same shape and having a magnetic pole surface are formed. In this embodiment, as shown in FIGS. 4 and 5, the inclination angle θ1 of the dividing line V1 of the permanent magnet M1 is set to θ1 ° = 90 ° −180 ° / P (P: the number of field portions). The opposing sides S1 and S1 between the permanent magnet portions 21 of the adjacent field portion 2 can be made parallel, and the magnetic pole area can be increased while reducing the leakage magnetic flux. The angle θ1 indicates the most desirable angle when the shape of the permanent magnet is the same for all the magnetic poles, and the shape of the permanent magnet is not necessarily equal. When the permanent magnet shape is different for each magnetic pole, θ1 may be different.

  The rare earth sintered magnet has high electrical conductivity, and eddy current loss is likely to occur due to the rotating magnetic field generated from the first stator 20. For this reason, the magnetic core 22 is made of a magnetic material having a lower electrical conductivity than that of the rare earth magnet, and the eddy current loss can be reduced by disposing the permanent magnet portion 21 on the first stator 20 side. In particular, when PWM control is performed, eddy current loss due to a change in high-frequency magnetic flux of the carrier component can be reduced. Further, if the magnetic core 22 is composed of a magnetic core having magnetic isotropy, eddy current loss can be hardly caused in the magnetic core 22. Further, since most of the field magnetic flux generated by the permanent magnet portion 21 on the first stator 20 side passes through the magnetic core 22, the surface on the first stator 20 side of the substantially fan-shaped magnetic core 22 is substantially Thus, it functions as a polar magnetic surface of the field part 2.

  In the present embodiment, two permanent magnet pieces 211 having right-angle trapezoidal magnetic pole faces are arranged with their hypotenuses S2 facing each other. Thus, in each field part 2, the length L1 in the frame radial direction at the central part of the permanent magnet part 21 can be made larger than the length L2 in the frame radial direction at the side edge part, and the air gap magnetic flux density Can be distributed close to a sine wave, and the induced ripple can be converted to a sine wave to reduce torque ripple. At this time, the magnetic core 22 may also have a length in the frame radial direction at the center portion larger than a length in the frame radial direction at the side edge portion. Specifically, it is preferable that the outer diameter of the magnetic core 22 from the center of the frame is maximized at the central portion and decreased toward the side edge portion. Further, the joining means between the pressing member 3 and the frame 1 is not limited to laser welding, and other joining methods such as rivet joining may be employed.

  As shown in FIGS. 1 and 2, the pressing member 3 fixes the field portions 2 respectively held in the plurality of field portion holding holes 15 of the frame 1 to the frame 1. In the present embodiment, the plurality of field portions 2 are fixed by laser-welding the pressing members 3 to both sides of the frame 1 in the direction of the rotation axis C.

  In the present embodiment, the pressing member 3 that fixes the field portion 2 on the first stator 20 side of the frame 1 is formed of a small-diameter ring component 31 and a large-diameter ring component 32, and the second of the frame 1 A pressing member 3 that fixes the field portion 2 on the stator 30 side is formed from a disk component 33. As shown in FIG. 1, a small-diameter ring component 31 is laser welded to the frame 1 in a state where a part of the inner edge of the magnetic pole surface on the first stator 20 side of the field part 2 is pressed. 32 is laser welded to the frame 1 in a state where a part of the outer edge of the magnetic pole surface on the first stator 20 side of the field part 2 is pressed. The disk component 33 is laser welded to the frame 1 in a state where the entire magnetic pole surface on the second stator 30 side of the field part 2 is pressed.

  The disk component 33 is formed of a soft magnetic electromagnetic steel plate and has a function of partially short-circuiting the magnetic flux on the second stator 30 side of the field part 2. With this function, when the magnetic attractive force acting between the second stator 30 and the rotor 10 is stronger than the magnetic attractive force acting between the first stator 20 and the rotor 10, the second stator 30 and the rotor 10 The magnetic attractive force acting during If this function is unnecessary, a ring component may be used instead of the disk component 33.

  Magnetization of the permanent magnet portion 21 of each field portion 2 may be performed after the field portion 2 is fixed to the frame 1 by the pressing member 3, or may be performed before the fixing, but after the fixing, the magnetization is performed. Magnetization is preferable in terms of handling the permanent magnet piece 211. This is because, since repulsive forces act on each other, it is difficult in terms of work to arrange the permanent magnet pieces 211 after magnetization.

  Thus, in the rotor 10 for an axial gap type rotating electrical machine of the present embodiment, the plurality of field portions 2 each have two identical permanent magnet pieces 211 each having a right-angled trapezoidal magnetic pole surface. Are arranged side by side so as to be larger than the width on the rotation axis side, and these two permanent magnet pieces 211 are divided lines V1 that incline the permanent magnet M1 having a rectangular magnetic pole surface with respect to the side thereof. Because it is formed in half, it is possible to use a permanent magnet excellent in the characteristics of a rectangular parallelepiped shape formed by a vertical magnetic field press with almost no waste, inexpensive and highly efficient axial gap type rotation An electric rotor can be provided.

  As described above, the axial gap type rotating electrical machine rotor 10 of the present embodiment has been described, but the present invention can be implemented in other forms.

  For example, you may implement like the rotor 50 for axial gap type rotary electric machines shown in FIGS. The rotor 50 is characterized in that the permanent magnet portion 23 of each field magnet portion 2 is configured by arranging a total of three permanent magnet pieces in the circumferential direction of the frame 1, and the other configuration is the same as that of the rotor 10 of the above embodiment. It is the same.

  As shown in FIG. 7, the rotor 50 includes two permanent magnet pieces 231 and 233 having the same shape in which the permanent magnet portion 23 of each field portion 2 has a right-angle trapezoidal magnetic pole surface, and these two permanent magnet pieces 231, One inner permanent magnet piece 232 having a rectangular magnetic pole surface, which is disposed between the two outer peripheral portions 233, has a circumferential width W3 on the outer peripheral side (outer peripheral portion 14 side) of the frame 1 and the rotational axis C side (inner peripheral portion). Are arranged side by side so as to be larger than the circumferential width W4 on the portion 12 side).

  Permanent magnet pieces 231 and 233 having right-sided trapezoidal magnetic pole faces obliquely bisect Nd-Fe-B (neodymium, iron, and boron) sintered magnets formed into a rectangular parallelepiped shape by a vertical magnetic field press. Is formed. That is, as shown in FIG. 8, a permanent magnet M2 formed by a vertical magnetic field press and having a rectangular magnetic pole surface is divided into two equal parts by a dividing line V2 inclined at an angle θ2 with respect to the side, thereby forming a right trapezoidal shape. Two permanent magnet pieces 231 and 233 having the same shape and having a magnetic pole surface are formed. In this modification, as shown in FIGS. 7 and 8, the inclination angle θ2 of the dividing line V2 of the permanent magnet M2 is θ2 ° = 90 ° −180 ° / P (P: the number of field portions). The opposing sides S3 and S3 of the permanent magnet portions 23 of the adjacent field portion 2 can be made parallel, and the magnetic pole area can be increased while reducing the leakage magnetic flux.

  Further, the inner permanent magnet piece 232 having a rectangular magnetic pole surface is formed of a Nd—Fe—B (neodymium, iron, boron) sintered magnet M3 formed into a rectangular parallelepiped shape by a vertical magnetic field press. In this embodiment, the length of the hypotenuse S4 of the permanent magnet pieces 231 and 233 having a right-angle trapezoidal magnetic pole surface is the same as the length of the long side S5 of the inner permanent magnet piece 232 having a rectangular magnetic pole surface. The lengths of the opposing sides (S4, S5) of the permanent magnet pieces 231 and 233 and the inner permanent magnet piece 232 can be made the same, and the magnetic pole surface of each field part 2 can be formed more effectively. .

  As described above, the rotor 50 has the inner permanent magnet piece 232 having a rectangular magnetic pole face disposed between the two permanent magnet pieces 231 and 233 having the same shape having a right trapezoidal magnetic pole face in each field portion 2. Therefore, each field part 2 can be made closer to a fan shape, and the magnetic pole surface of each field part 2 can be formed more effectively.

  In addition, it is preferable that the residual magnetic flux density of the permanent magnet pieces 231 and 233 on both outer sides in the frame circumferential direction is smaller than the residual magnetic flux density of the inner permanent magnet piece 232 on the inner side in the frame circumferential direction. Thus, the air gap magnetic flux density can be distributed close to a sine wave, and the induced voltage can be converted to a sine wave to reduce torque ripple.

  Moreover, it is preferable that the coercive force of the permanent magnet pieces 231 and 233 on both outer sides in the frame circumferential direction is larger than the coercive force of the inner permanent magnet piece 232 on the inner side in the frame circumferential direction. Thus, the permanent magnet pieces on both outer sides in the circumferential direction of the frame are more easily demagnetized, and this can be dealt with. Since the permanent magnet pieces 231 and 233 on both outer sides in the frame circumferential direction and the inner permanent magnet piece 232 on the inner side in the frame circumferential direction are not manufactured by cutting from one magnet, they are manufactured from different magnets. It is easy.

  Moreover, it is preferable that the coercive force of the permanent magnet piece 233 on the reverse side in the rotational direction of the frame is larger than the coercive force of the permanent magnet piece 231 on the forward side in the rotational direction of the frame. As a result, the permanent magnet piece on the reverse side in the rotational direction of the frame has a larger demagnetizing field at the time of driving and can easily cope with demagnetization. However, if the magnet shape is the same, there is a risk that the magnet material may be mistaken, so magnets with different coercive forces are cut in advance with rectangular magnets of different sizes to prevent errors in relation to the frame shape. It is also possible. As described above, the number of permanent magnet pieces constituting the rotor field portion, the arrangement direction, the size of each permanent magnet piece, the combination of magnetic characteristics, etc., the performance required for the axial gap type rotating electrical machine, etc. Various design changes are possible depending on the situation.

  Further, as shown in FIG. 9, two permanent magnet pieces 241 having the same shape and having right-angled triangular magnetic pole faces in each field portion holding hole 15 of the frame as the permanent magnet portions 24 constituting each field portion of the rotor. 243 and one inner permanent magnet piece 242 having a rectangular magnetic pole surface disposed between the two permanent magnet pieces 241 and 243, the width on the outer peripheral side of the frame is larger than the width on the rotation axis side. May be arranged to be larger.

  The permanent magnet pieces 241 and 243 having right-angled triangular magnetic pole surfaces bisect an Nd—Fe—B (neodymium, iron, boron) sintered magnet formed into a rectangular parallelepiped shape by a vertical magnetic field press. Is formed. That is, as shown in FIG. 9B, the permanent magnet M4 formed by vertical magnetic field press and having a rectangular magnetic pole face is divided into two equal parts by a dividing line V3 which is a diagonal line inclined by an angle θ3 with respect to the side. Thus, two permanent magnet pieces 241 and 243 having the same shape and having a right triangular magnetic pole surface are formed. The inner permanent magnet piece 242 having a rectangular magnetic pole surface is formed of an Nd—Fe—B (neodymium / iron / boron) sintered magnet M5 formed in a rectangular parallelepiped shape by a vertical magnetic field press.

  Further, as shown in FIG. 10, two permanent magnet pieces 251 having the same shape and having a right-angle trapezoidal magnetic pole surface in each field portion holding hole 15 of the frame as the permanent magnet portion 25 constituting each field portion of the rotor. 253 and one inner permanent magnet piece 252 having an isosceles trapezoidal magnetic pole surface, which is arranged between these two permanent magnet pieces 251 and 253, the width on the outer peripheral side of the frame is on the rotation axis side. You may arrange so that it may become larger than a width | variety.

  The permanent magnet pieces 251 and 253 having a right-angle trapezoidal magnetic pole surface and the permanent magnet pieces 252 having an isosceles trapezoidal magnetic pole surface are Nd—Fe—B type (neodymium / iron) formed into a rectangular parallelepiped shape by a vertical magnetic field press. (Boron) Sintered magnet is formed by obliquely dividing it into three parts. That is, as shown in FIG. 10B, a permanent magnet M6 formed by vertical magnetic field press and having a rectangular magnetic pole face is symmetrically formed by two dividing lines V4 inclined at an equal angle θ4 with respect to the side. By dividing, two permanent magnet pieces 251 and 253 having right-angle trapezoidal magnetic pole surfaces and one permanent magnet piece 252 having isosceles trapezoidal magnetic pole surfaces are formed. In this embodiment, the inclination angle θ4 of the dividing line V4 of the permanent magnet M6 is 2 × θ4 ° = 180 ° −180 ° / P (P: the number of field portions). The opposing sides of the permanent magnet portions 25 can be made parallel, and the magnetic pole area can be increased while reducing the leakage magnetic flux.

  In this embodiment, two permanent magnet pieces having right-angled triangular magnetic pole faces may be used instead of the two permanent magnet pieces 251 and 253 having right-angle trapezoidal magnetic pole faces. Further, instead of the permanent magnet piece 252 having an isosceles trapezoidal magnetic pole face, a permanent magnet piece having an isosceles triangular magnetic pole face may be used. Permanent magnet pieces having right-angled triangular magnetic pole faces and permanent magnet pieces having isosceles triangular magnetic pole faces can also be formed by obliquely dividing a permanent magnet formed into a rectangular parallelepiped shape by a vertical magnetic field press. it can.

  Further, as shown in FIG. 11, two permanent magnet pieces 261 having the same shape and having a right-angle trapezoidal magnetic pole face in each field portion holding hole 15 of the frame as the permanent magnet portion 26 constituting each field portion of the rotor. 264 and two inner permanent magnet pieces 262 and 263 having the same shape with right-angled trapezoidal magnetic pole surfaces arranged between these two permanent magnet pieces 261 and 264, the width on the outer peripheral side of the frame is rotated. You may arrange so that it may become larger than the width | variety in the axial center side.

  Permanent magnet pieces 261 and 264 having right-angled trapezoidal magnetic pole surfaces obliquely bisect Nd-Fe-B (neodymium, iron, boron) sintered magnets formed into a rectangular parallelepiped shape by a vertical magnetic field press. Is formed. That is, as shown in FIG. 11B, one permanent magnet M7 formed by a vertical magnetic field press and having a rectangular magnetic pole face is divided into two equal parts by a dividing line V5 inclined at an angle θ5 with respect to the side. Thus, two permanent magnet pieces 261 and 264 having the same shape and having a right trapezoidal magnetic pole surface are formed.

  In addition, the inner permanent magnet pieces 262 and 263 having right-angled trapezoidal magnetic pole surfaces are also formed by obliquely inserting Nd—Fe—B (neodymium / iron / boron) sintered magnets formed into a rectangular parallelepiped shape by a vertical magnetic field press. It is formed equally. That is, as shown in FIG. 11 (b), another permanent magnet M8 formed by vertical magnetic field press and having a rectangular magnetic pole face is bisected by a dividing line V6 inclined at an angle θ6 with respect to the side. Thus, two permanent magnet pieces 262 and 263 having the same shape and having a right-angle trapezoidal magnetic pole surface are formed. In this embodiment, the inclination angle θ5 of the dividing line V5 and the inclination angle θ6 of the dividing line V6 are set to θ5 ° + θ6 ° = 180 ° −180 ° / P (P: the number of field portions). The opposing sides of the matching permanent magnet portions 26 of the field portion can be made parallel, and the magnetic pole area can be increased while reducing the leakage magnetic flux.

  In this embodiment, instead of the two permanent magnet pieces 261 and 264 having a right trapezoidal magnetic pole face, two permanent magnet pieces having a right triangular pole face may be used. Further, instead of the two inner permanent magnet pieces 262 and 263 having a right trapezoidal magnetic pole face, two inner permanent magnet pieces having a right triangular pole face may be used. The permanent magnet piece having the right triangular magnetic pole face and the inner permanent magnet piece can also be formed by obliquely dividing the permanent magnet formed into a rectangular parallelepiped shape by a vertical magnetic field press.

  Further, like the rotor 60 shown in FIG. 12, the magnetic poles 4 may be disposed between the plurality of field portions 2 with a predetermined distance from each field portion 2. That is, the frame 5 of the rotor 60 includes an inner peripheral portion 52 having a shaft hole 51 through which a rotation shaft can be inserted, a spoke portion 53 that protrudes radially from the outer surface of the inner peripheral portion 52, and the spoke portion 53. The outer peripheral part 54 provided at the tip of the inner peripheral part 52, and the outer peripheral surface of these inner peripheral part 52, the side surface of each spoke part 53, and the inner side surface of the outer peripheral part 54, a total of six fan-shaped A field portion holding hole 55 is provided. A magnetic pole holding hole 56 is formed in each spoke portion 53, and the rectangular parallelepiped magnetic pole 4 is accommodated in the magnetic pole holding hole 56. These magnetic poles 4 are made of a soft magnetic material, and increase the reluctance torque generated due to the difference between the q-axis inductance and the d-axis inductance by increasing the so-called q-axis inductance.

  Moreover, in each field part 2, you may provide the recessed part or convex part which positions these permanent magnet pieces in the surface where several permanent magnet pieces of magnetic body core 22 contact | connect. Thus, a plurality of permanent magnet pieces can be combined and fixed to the frame more stably and reliably.

  Moreover, in the said embodiment, although the several permanent magnet piece 211 is accommodated in the field part holding | maintenance hole 15 of the flame | frame 1, and it fixes with the pressing member 3, this invention is not limited to this, For example, a plurality of permanent magnet pieces may be fixed to a disk-shaped frame using an adhesive. Further, the stator is also optional, and both the second stator and the third stator may have coils.

  In addition, the present invention can be carried out in a mode in which various improvements, modifications and variations are added based on the knowledge of those skilled in the art without departing from the spirit of the present invention. It may be implemented in a form in which any invention specific matter is replaced with another technology within a range where the same action or effect occurs, or the invention specific matter configured integrally may be constituted by a plurality of members. In addition, the invention specific items constituted by a plurality of members may be implemented in an integrated configuration.

DESCRIPTION OF SYMBOLS 100: Axial gap type rotary electric machine 10, 50, 60: Rotor 1, 5: Frame 2: Field part 21, 23, 24, 25, 26: Permanent magnet part 211, 231, 233, 241, 243, 251, 253 , 261, 264: Permanent magnet pieces 232, 242, 252, 262, 263: Inner permanent magnet pieces 22: Magnetic core 3: Pressing member 20: First stator 30: Second stator 40: Rotating axis C: Rotating axis M1 to M8: permanent magnets V1 to V6: parting line S2: hypotenuse W1, W3: width W2 of the field part on the frame outer periphery side, W4: width of the field part on the frame rotation axis side

Claims (11)

A rotor for an axial gap type rotating electrical machine, comprising: a frame rotatable around a rotation axis; and a plurality of field portions disposed around an axis of rotation of the frame and having a magnetic pole surface on an axial end surface. There,
Each field part is configured by arranging two permanent magnet pieces having right-angled trapezoidal or right-angled triangular magnetic pole faces so that the width on the outer peripheral side of the frame is larger than the width on the rotation axis side,
A rotor for an axial gap type rotating electrical machine, wherein the two permanent magnet pieces are formed by dividing a permanent magnet having a rectangular magnetic pole surface into two equal parts by a dividing line inclined with respect to the side thereof.   The rotor for an axial gap type rotating electrical machine according to claim 1, wherein an inner permanent magnet piece having a rectangular magnetic pole face is disposed between the two permanent magnet pieces. A rotor for an axial gap type rotating electrical machine, comprising: a frame rotatable around a rotation axis; and a plurality of field portions disposed around an axis of rotation of the frame and having a magnetic pole surface on an axial end surface. There,
Each of the field portions has two permanent magnet pieces each having a right trapezoid or right triangle pole face, and one inner permanent magnet piece having an isosceles trapezoid pole face disposed between the two permanent magnet pieces; Are arranged side by side so that the width on the outer peripheral side of the frame is larger than the width on the rotational axis side,
The two permanent magnet pieces and the one inner permanent magnet piece are formed by dividing a permanent magnet having a rectangular magnetic pole surface by two dividing lines inclined at an equal angle with respect to the side thereof. Axial gap type rotating electrical machine rotor. A rotor for an axial gap type rotating electrical machine, comprising: a frame rotatable around a rotation axis; and a plurality of field portions disposed around an axis of rotation of the frame and having a magnetic pole surface on an axial end surface. There,
Two permanent magnet pieces each having a right trapezoid or right triangle pole face, and two inner permanent magnets having a right trapezoid or right triangle pole face disposed between the two permanent magnet pieces. The pieces are arranged side by side so that the width on the outer peripheral side of the frame is larger than the width on the rotation axis side,
The two permanent magnet pieces are formed by dividing a permanent magnet having a rectangular magnetic pole surface into two equal parts by a dividing line inclined with respect to the side thereof,
For the axial gap type rotating electrical machine, wherein the two inner permanent magnet pieces are formed by equally dividing another permanent magnet having a rectangular magnetic pole surface by a dividing line inclined with respect to the side thereof. Rotor.   The rotor for an axial gap type rotating electrical machine according to any one of claims 1 to 4, wherein the two permanent magnet pieces are arranged with their hypotenuses facing each other.   The rotor for an axial gap type rotating electrical machine according to any one of claims 2 to 5, wherein the lengths of the opposing sides of the permanent magnet piece and the inner permanent magnet piece are substantially the same.   The rotor for an axial gap type rotating electrical machine according to any one of claims 2 to 6, wherein a residual magnetic flux density of the inner permanent magnet piece is larger than a residual magnetic flux density of the permanent magnet piece.   The rotor for an axial gap type rotating electrical machine according to any one of claims 2 to 6, wherein a coercive force of the inner permanent magnet piece is smaller than a coercive force of the permanent magnet piece.   The axial gap type rotation according to any one of claims 1 to 6, wherein the coercive force of the permanent magnet piece on the reverse side in the rotational direction of the frame is larger than the coercive force of the permanent magnet piece on the forward side in the rotational direction of the frame. Electric rotor.   10. The rotor for an axial gap type rotating electrical machine according to claim 1, wherein each of the field magnet portions includes a substantially fan-shaped magnetic core superimposed on the permanent magnet piece or the inner permanent magnet piece. .   The rotor for an axial gap type rotating electric machine according to any one of claims 1 to 10, wherein the permanent magnet is an Nd-Fe-B sintered magnet.

Images