JP7335831B2 - ROTOR AND ARC MAGNET MANUFACTURING METHOD FOR ROTATING ELECTRIC MACHINE - Google Patents

Description

The present invention relates to a rotor of a rotary electric machine mounted on an electric vehicle or the like, and an arc magnet manufacturing method for producing each arc magnet of the rotor of the rotary electric machine.

2. Description of the Related Art Electric vehicles such as hybrid vehicles, battery-powered vehicles, and fuel cell vehicles have conventionally been equipped with rotating electric machines such as electric motors and generators. With the popularization of these electric vehicles, there is a growing demand for improved output performance of rotary electric machines mounted on the electric vehicles.

Therefore, for example, Patent Document 1 discloses a rotor of a rotating electric machine in which a plurality of layers of permanent magnets are arranged in the radial direction, and which has an outer diameter side arc magnet and a pair of inner diameter side arc magnets. As a result, the magnet torque in each magnetic pole portion of the rotor can be increased, so that the output performance of the rotary electric machine can be improved.

JP 2018-102039 A

However, in the pair of inner circular arc magnets of the rotor of Patent Document 1, a region is formed through which the interlinking magnetic flux of the d-axis current does not pass through the outer circular arc magnets. Each area of the inner arc magnet through which the interlinking magnetic flux does not pass through the outer arc magnet has a low permeance and thus is easily demagnetized. If demagnetization occurs in the rotor magnet, the output performance of the rotating electrical machine will decrease. This was an impediment to improving performance.

The present invention provides a rotor of a rotary electric machine capable of suppressing demagnetization occurring in the arc magnet, and an arc magnet manufacturing method for producing each arc magnet of the rotor of the rotary electric machine.

The first invention is
a substantially annular rotor core;
a plurality of magnetic pole portions formed at predetermined intervals in the circumferential direction of the rotor core,
Each magnetic pole is
an outer diameter side magnet portion composed of at least one outer diameter side arc magnet arranged so as to protrude radially inward;
an inner diameter side magnet portion positioned radially inward of the outer diameter side magnet portion and configured from at least a pair of inner diameter side arc magnets arranged so as to protrude inward in the radial direction. death,
Each arc magnet is an arc magnet in which the inner peripheral surface and the outer peripheral surface have the same arc center,
When the central axis of each magnetic pole portion is the d-axis and the axis separated by an electrical angle of 90 degrees from the d-axis is the q-axis,
The inner diameter side magnet portion is formed symmetrically with respect to the d-axis,
The pair of inner diameter arc magnets are
a first inner diameter arc magnet located on one side of the d-axis in the circumferential direction and having a d-axis side end on the d-axis side and a q-axis side end on the q-axis side;
a second inner diameter arc magnet located on the other side of the d-axis in the circumferential direction and having a d-axis side end on the d-axis side and a q-axis side end on the q-axis side; A rotor of a rotating electric machine,
The outer diameter arc magnet, the first inner diameter arc magnet, and the second inner diameter arc magnet have substantially the same shape when viewed from the axial direction,
The q-axis side end of the first inner diameter arc magnet is positioned between the center of the arc of the outer diameter arc magnet and the first end located on the one side in the circumferential direction of the outer diameter arc magnet. is arranged to be outside in the circumferential direction from the first imaginary straight line passing through,
The q-axis side end of the second inner diameter arc magnet is a second end located on the other side in the circumferential direction of the outer diameter arc magnet and the arc center of the outer diameter arc magnet. and arranged so as to be outside in the circumferential direction of the second imaginary straight line passing through,
The first inner diameter arc magnet and the second inner diameter arc magnet have a higher intrinsic coercive force than the outer diameter arc magnet.

The second invention is
a substantially annular rotor core;
a plurality of magnetic pole portions formed at predetermined intervals in the circumferential direction of the rotor core,
Each magnetic pole is
an outer diameter side magnet portion composed of at least one outer diameter side arc magnet arranged so as to protrude radially inward;
an inner diameter side magnet portion positioned radially inward of the outer diameter side magnet portion and configured from at least a pair of inner diameter side arc magnets arranged so as to protrude inward in the radial direction. death,
Each arc magnet is an arc magnet in which the inner peripheral surface and the outer peripheral surface have the same arc center,
When the central axis of each magnetic pole portion is the d-axis and the axis separated by an electrical angle of 90 degrees from the d-axis is the q-axis,
The inner diameter side magnet portion is formed symmetrically with respect to the d-axis,
The pair of inner diameter arc magnets are
a first inner diameter arc magnet located on one side of the d-axis in the circumferential direction and having a d-axis side end on the d-axis side and a q-axis side end on the q-axis side;
a second inner diameter arc magnet located on the other side of the d-axis in the circumferential direction and having a d-axis side end on the d-axis side and a q-axis side end on the q-axis side; A rotor of a rotating electric machine,
The outer diameter arc magnet, the first inner diameter arc magnet, and the second inner diameter arc magnet have substantially the same shape when viewed from the axial direction,
The q-axis side end of the first inner diameter arc magnet is positioned between the center of the arc of the outer diameter arc magnet and the first end located on the one side in the circumferential direction of the outer diameter arc magnet. , and the d-axis side end portion is arranged to be inner than the first imaginary line in the circumferential direction,
The q-axis side end of the second inner diameter arc magnet is a second end located on the other side in the circumferential direction of the outer diameter arc magnet and the arc center of the outer diameter arc magnet. and the d-axis side end is arranged to be inner than the second imaginary line in the circumferential direction, and
In the first inner diameter arc magnet, a coercive force having a higher intrinsic coercive force than that of the outer diameter arc magnet is provided in a region including the q-axis side end and outside the first imaginary straight line in the circumferential direction. An enlarged part is formed,
In the second inner diameter arc magnet, a coercive force having a higher intrinsic coercive force than that of the outer diameter arc magnet is provided in a region including the q-axis side end portion and outside the second imaginary straight line in the circumferential direction. An augmentation is formed.

According to the first invention, since the first inner arc magnet and the second inner arc magnet have a higher intrinsic coercive force than the outer arc magnet, the interlinkage magnetic flux that does not pass through the outer arc magnet passes through the second inner arc magnet. It is possible to suppress the demagnetization that occurs in each region of the first inner diameter arc magnet and the second inner diameter arc magnet.

According to the second invention, the coercive force increasing portion having a high intrinsic coercive force can be provided in each region of the first inner diameter arc magnet and the second inner diameter arc magnet through which the interlinkage magnetic flux that does not pass through the outer diameter arc magnet passes. Therefore, demagnetization occurring in each region of the first inner arc magnet and the second inner arc magnet through which interlinkage magnetic flux that does not pass through the outer arc magnet can be suppressed.

It is the front view which looked at the rotor of the rotary electric machine of 1st Embodiment of this invention from the axial direction. 2 is an enlarged view of the vicinity of the magnetic pole portion of the rotor of the rotary electric machine of FIG. 1; FIG. 1. It is a figure explaining the manufacturing method of each arc magnet of the rotor of the rotary electric machine of FIG. A case where an arc magnet having a higher coercive force than an outer diameter arc magnet is used for the first inner diameter arc magnet and the second inner diameter arc magnet, and an outer 2 is a graph comparing the demagnetization index according to the temperature of an arc magnet in the case of using an arc magnet having the same coercive force as that of a radius side arc magnet. FIG. 7 is an enlarged view of the vicinity of the magnetic pole portion of the rotor of the rotary electric machine according to the second embodiment of the present invention; It is an enlarged view around the magnetic pole part of the rotor of the rotary electric machine of 3rd Embodiment of this invention.

Hereinafter, each embodiment of the rotor of the rotary electric machine of the present invention will be described based on the accompanying drawings.

[First embodiment]
First, a rotor 10 of a rotary electric machine according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 4. FIG.

(rotor)
As shown in FIG. 1, a rotor 10 of a rotary electric machine according to one embodiment of the present invention is attached to the outer peripheral portion of a rotor shaft (not shown) and has a substantially annular rotor core 20 centered on an annular center CL. , and a plurality of magnetic pole portions 30 (12 pieces in this embodiment) formed at predetermined intervals in the circumferential direction of the rotor core 20 . The rotor 10 is arranged inside the stator (not shown).

In this specification and the like, the axial direction, the radial direction, and the circumferential direction refer to directions based on the ring center CL of the rotor 10 unless otherwise specified.

The rotor core 20 is formed by laminating a plurality of substantially annular magnetic steel sheets 200 having the same shape in the axial direction. The rotor core 20 has a rotor shaft hole 21 concentric with the ring center CL. Further, the center axis of each magnetic pole portion 30 connecting the ring center CL and the center of each magnetic pole portion 30 is the d-axis (d-axis in the drawing), and the axis separated by an electrical angle of 90 degrees from the d-axis is the q-axis. (q-axis in the drawing), each magnetic pole portion 30 of the rotor core 20 is formed to intersect the d-axis and has an outer diameter side magnet insertion hole 410 having a shape symmetrical with respect to the d-axis. Each magnetic pole portion 30 of the rotor core 20 is provided with a pair of inner diameter side magnet insertion holes 420 located radially inside the outer diameter side magnet insertion holes 410 and formed symmetrically with respect to the d-axis. Both the outer diameter side magnet insertion hole 410 and the pair of inner diameter side magnet insertion holes 420 have an arc shape that protrudes inward in the radial direction.

Each magnetic pole portion 30 of the rotor core 20 is provided with a gap portion 60 formed to intersect the d-axis in the circumferential direction between the pair of inner diameter side magnet insertion holes 420 . The rotor core 20 is provided with a pair of ribs 50 extending radially between the pair of inner diameter side magnet insertion holes 420 and the gap 60 .

The rotor core 20 includes a first lightening hole 71 formed at a position that intersects the d-axis radially inside the air gap 60 of each magnetic pole portion 30, and a first lightening hole 71 that is formed at a position intersecting the q-axis between the adjacent magnetic pole portions 30. and a second lightening hole 72 formed. The first lightening hole 71 has a shape symmetrical with respect to the d-axis. The second lightening hole 72 has a shape symmetrical with respect to the q-axis.

Each magnetic pole portion 30 has an outer diameter side magnet portion 310 and an inner diameter side magnet portion 320 located radially inward of the outer diameter side magnet portion 310 . The outer diameter side magnet portion 310 is composed of outer diameter side arc magnets 810 arranged so as to protrude inward in the radial direction. The inner diameter side magnet portion 320 is composed of at least a pair of inner diameter side arc magnets 820 arranged so as to protrude inward in the radial direction. The outer diameter side magnet portion 310 and the inner diameter side magnet portion 320 are formed symmetrically with respect to the d-axis.

Outer diameter arc magnets 810 forming outer diameter magnet portion 310 are inserted into outer diameter magnet insertion holes 410 of rotor core 20 . A pair of inner diameter side arc magnets 820 constituting inner diameter side magnet portion 320 are inserted into a pair of inner diameter side magnet insertion holes 420 of rotor core 20 .

The outer diameter side arc magnet 810 and the pair of inner diameter side arc magnets 820 are magnetized in the radial direction. In addition, the outer diameter side arc magnet 810 and the pair of inner diameter side arc magnets 820 have magnetization directions different from those of the adjacent magnetic pole portions 30, and the magnetic pole portions 30 are arranged so that the magnetization directions are alternately different in the circumferential direction.

(Magnetic pole)
As shown in FIG. 2, the pair of inner diameter side magnet insertion holes 420 includes a first inner diameter side magnet insertion hole 421 formed on one side (left side in FIG. 2) in the circumferential direction with respect to the d-axis and a and a second inner diameter side magnet insertion hole 422 formed on the other side (right side in FIG. 2) in the circumferential direction.

The first inner diameter side magnet insertion hole 421 and the second inner diameter side magnet insertion hole 422 are provided in a substantially V shape that widens outward in the radial direction so that the circumferential distance between them increases. .

The pair of inner diameter arc magnets 820 are inserted into the first inner diameter magnet insertion holes 421, and are located on one side (left side in FIG. 2) in the circumferential direction with respect to the d-axis. and a second inner diameter arc magnet 822 inserted into the second inner diameter magnet insertion hole 422 and located on the other side (on the right side in FIG. 2) in the circumferential direction with respect to the d-axis.

Each magnetic pole portion 30 of the rotor core 20 includes a first rotor yoke portion 221 formed radially outside the outer diameter side magnet insertion hole 410 and extending in the circumferential direction, an outer diameter side magnet insertion hole 410 and the first inner diameter side magnet insertion hole 410 . A second rotor yoke portion 222 that is formed between the hole 421 and the second inner diameter side magnet insertion hole 422 , curves to protrude radially inward and extends in the circumferential direction, and the first inner diameter side magnet insertion hole 421 . and a third rotor yoke portion 223 that is formed radially inward of the second inner diameter side magnet insertion hole 422 and that curves to project radially inward and extends in the circumferential direction.

Hereinafter, in order to simplify and clarify the description in this specification and the like, when the rotor 10 is viewed from the axial direction, the ring center CL is downward and the outer diameter side in the d-axis direction is upward. For convenience, the side (the left side as viewed in FIG. 2) is defined as the left side, and the other side in the circumferential direction (the right side as viewed in FIG. 2) is defined as the right side. In this specification and the like, the inner side in the circumferential direction refers to the central side of each magnetic pole portion 30 in the circumferential direction, that is, the d-axis side, and the outer side in the circumferential direction refers to both end sides of each magnetic pole portion 30 in the circumferential direction. , that is, the q-axis side.

The outer diameter side arc magnet 810 has an inner peripheral surface 810N and an outer peripheral surface 810F having the same arc center C10, a left end portion 810L located on one side in the circumferential direction, and a right end portion 810R located on the other side in the circumferential direction. and have The arc center C10 of the outer diameter side arc magnet 810 is located on the d-axis. The inner peripheral surface 810N of the outer diameter side arc magnet 810 has a substantially arc shape with an inner peripheral radius r10N centered on the arc center C10. The outer peripheral surface 810F of the outer diameter side arc magnet 810 has a substantially arc shape with an outer peripheral radius r10F centered on the arc center C10. The thickness t10 of the outer diameter side arc magnet 810 is substantially the same as the value of (outer circumference radius r10F)-(inner circumference radius r10N).

The first inner diameter side arc magnet 821 has an inner peripheral surface 821N and an outer peripheral surface 821F having the same arc center C21, a q-axis side end portion 821Q, and a d-axis side end portion 821D. The arc center C21 of the first inner diameter arc magnet 821 is located on the right side of the d-axis on the side opposite to the first inner diameter arc magnet 821 . The inner peripheral surface 821N of the first inner diameter side arc magnet 821 has a substantially arc shape with an inner peripheral radius r21N centered on the arc center C21. The outer peripheral surface 821F of the first inner diameter side arc magnet 821 has a substantially arc shape with an outer peripheral radius r21F centered on the arc center C21. The thickness t21 of the first inner diameter side arc magnet 821 is substantially the same as the value of (outer circumference radius r21F)-(inner circumference radius r21N).

The second inner diameter side arc magnet 822 has an inner peripheral surface 822N and an outer peripheral surface 822F having the same arc center C22, a q-axis side end portion 822Q, and a d-axis side end portion 822D. The arc center C22 of the second inner diameter arc magnet 822 is positioned on the left side of the d-axis on the side opposite to the second inner diameter arc magnet 822 . The inner peripheral surface 822N of the second inner diameter side arc magnet 822 has a substantially arc shape with an inner peripheral radius r22N centered on the arc center C22. The outer peripheral surface 822F of the second inner diameter side arc magnet 822 has a substantially arc shape with an outer peripheral radius r22F centered on the arc center C22. The thickness t22 of the second inner diameter side arc magnet 822 is substantially the same as the value of (outer circumference radius r22F)-(inner circumference radius r22N).

The arc center C21 of the first inner diameter arc magnet 821 is located on the right side of the d-axis on the side opposite to the first inner diameter arc magnet 821, and the arc center C22 of the second inner diameter arc magnet 822 is located at d Since it is located on the left side of the axis opposite to the second inner arc magnet 822, the distance L11 between the first inner arc magnet 821 and the outer arc magnet 810 and the second inner arc magnet 822 and The distance L12 from the outer diameter side arc magnet 810 increases from the q-axis toward the d-axis.

As a result, an increase in the circumferential length of the magnetic pole portions 30 can be suppressed, and an increase in the size of the rotor 10 can be suppressed. In addition, the magnetic path along the q-axis (hereinafter also referred to as the q-axis magnetic path) in the rotor 10 can be widened, and the reluctance torque of the rotating electrical machine can be increased, so that the output performance of the rotating electrical machine can be improved. Furthermore, the magnetic flux generated by the first inner diameter arc magnet 821, the second inner diameter arc magnet 822, and the outer diameter arc magnet 810 is easily concentrated on the d-axis, so that the magnet torque of the rotating electric machine can be efficiently used. The output performance of the rotary electric machine can be improved.

In addition, since the first inner-diameter arc magnet 821 and the second inner-diameter arc magnet 822 are arc magnets arranged so as to protrude inward in the radial direction, the outer-diameter magnet insertion hole 410 and the first inner-diameter arc magnet 821 and the first inner-diameter arc magnet 822 The q-axis magnetic path formed between the side magnet insertion hole 421 and the q-axis magnetic path formed between the outer diameter side magnet insertion hole 410 and the second inner diameter side magnet insertion hole 422 are defined by the magnetic resistance. It can be made into a lesser shape.

Furthermore, the q-axis side end 821Q of the first inner diameter arc magnet 821 is a first imaginary straight line passing through the arc center C10 of the outer diameter arc magnet 810 and the left end 810L of the outer diameter arc magnet 810. VL1 is circumferentially outward, and the d-axis side end portion 821D is disposed circumferentially inner than the first imaginary straight line VL1. The q-axis side end portion 822Q of the second inner diameter arc magnet 822 extends from the second imaginary straight line VL2 passing through the arc center C10 of the outer diameter arc magnet 810 and the right end portion 810R of the outer diameter arc magnet 810. , and the d-axis side end portion 822D is arranged so as to be circumferentially inner than the second imaginary straight line VL2.

Therefore, the first inner diameter arc magnet 821 includes the q-axis side end 821Q, and the outer diameter arc of the interlinkage magnetic flux due to the d-axis current is generated in the region outside the first imaginary straight line VL1 in the circumferential direction. A region S is formed through which interlinkage magnetic flux that does not pass through the magnet 810 passes. Similarly, the second inner diameter side arc magnet 822 includes a q-axis side end portion 822Q, and in a region outside the second imaginary straight line VL2 in the circumferential direction, out of the interlinkage magnetic flux due to the d-axis current, the outer diameter side A region S is formed through which interlinkage magnetic flux that does not pass through the arc magnet 810 passes. The region S of the first inner diameter arc magnet 821 and the second inner diameter arc magnet 822 through which the interlinking magnetic flux does not pass through the outer diameter arc magnet 810 has a low permeance and is easily demagnetized.

The outer diameter side arc magnet 810, the first inner diameter side arc magnet 821, and the second inner diameter side arc magnet 822 are, for example, ring magnets formed by molding using a hot working process such as hot extrusion. It is possible to use an arc magnet cut into two pieces.

In this embodiment, the thickness t10 of the outer diameter side arc magnet 810, the thickness t21 of the first inner diameter side arc magnet 821, and the thickness t22 of the second inner diameter side arc magnet 822 are the same thickness. there is The inner radius r10N of the inner peripheral surface 810N of the outer diameter side arc magnet 810, the inner radius r21N of the inner peripheral surface 821N of the first inner diameter side arc magnet 821, and the inner circumference surface 822N of the second inner diameter side arc magnet 822 The inner circumference radius r22N has the same length. What is the outer radius r10F of the outer peripheral surface 810F of the outer diameter side arc magnet 810, the outer peripheral radius r21F of the outer peripheral surface 821F of the first inner diameter side arc magnet 821, and the outer peripheral radius r22F of the outer peripheral surface 822F of the second inner diameter side arc magnet 822? , have the same length.

Therefore, the outer diameter side arc magnet 810, the first inner diameter side arc magnet 821, and the second inner diameter side arc magnet 822 have substantially the same shape when viewed in the axial direction. As a result, since the same arc magnet can be used for the outer diameter side arc magnet 810, the first inner diameter side arc magnet 821, and the second inner diameter side arc magnet 822, the outer diameter side arc magnet 810 and the first inner diameter side arc magnet The manufacturing cost of 821 and the second inner diameter arc magnet 822 can be reduced.

Furthermore, in the present embodiment, when viewed from the axial direction, the angle θ10 between the left end portion 810L and the right end portion 810R of the outer diameter side arc magnet 810 centered on the arc center C10 of the outer diameter side arc magnet 810, The angle θ21 between the q-axis side end 821Q and the d-axis side end 821D centered on the arc center C21 of the first inner diameter arc magnet 821 and the arc center C22 of the second inner diameter arc magnet 822 , the angle θ22 formed by the q-axis side end portion 822Q and the d-axis side end portion 822D is preferably an angle that is 360 degrees when multiplied by an integral number. Thus, by cutting the ring magnet radially at intervals of the angle θ10 formed in the circumferential direction, the outer diameter arc magnet 810 can be manufactured, and the ring magnet is cut radially at intervals of the angle θ21 formed in the circumferential direction. Thus, the first inner-diameter arc magnet 821 can be manufactured, and the second inner-diameter arc magnet 822 can be manufactured by radially cutting the ring magnet at intervals of the angle θ22 formed in the circumferential direction. Therefore, the outer diameter side arc magnet 810, the first inner diameter side arc magnet 821, and the second inner diameter side arc magnet 822 can be manufactured from the ring magnet without generating a surplus. The manufacturing cost of the first inner diameter arc magnet 821 and the second inner diameter arc magnet 822 can be further reduced.

In this embodiment, the formed angle θ10, the formed angle θ21, and the formed angle θ22 are substantially the same. That is, the outer diameter side arc magnet 810, the first inner diameter side arc magnet 821, and the second inner diameter side arc magnet 822 have substantially the same shape when viewed from the axial direction. As a result, since the same arc magnet can be used for the outer diameter side arc magnet 810, the first inner diameter side arc magnet 821, and the second inner diameter side arc magnet 822, the outer diameter side arc magnet 810 and the first inner diameter side arc magnet The manufacturing cost of 821 and the second inner diameter arc magnet 822 can be further reduced.

The outer diameter side magnet insertion hole 410 has an inner peripheral wall surface 410N and an outer peripheral wall surface 410F facing the inner peripheral surface 810N and the outer peripheral surface 810F of the outer diameter side arc magnet 810, respectively, a left wall surface 410L, and a right wall surface 410R. . The first inner diameter side magnet insertion hole 421 includes an inner peripheral wall surface 421N and an outer peripheral wall surface 421F facing the inner peripheral surface 821N and the outer peripheral surface 821F of the first inner diameter side arc magnet 821, a q-axis side wall surface 421Q, and a d-axis side wall surface. and a wall surface 421D. The second inner diameter side magnet insertion hole 422 includes an inner peripheral wall surface 422N and an outer peripheral wall surface 422F facing the inner peripheral surface 822N and the outer peripheral surface 822F of the second inner diameter arc magnet 822, a q-axis side wall surface 422Q, and a d-axis side wall surface. and a wall surface 422D.

(Gap)
The gap 60 is provided between the d-axis side wall surface 421D of the first inner diameter arc magnet 821 and the d-axis side wall surface 422D of the second inner diameter magnet insertion hole 422 in the circumferential direction so as to intersect the d-axis. formed.

As a result, in the inner diameter side magnet portion 320, a gap is formed on the d-axis, so that the d-axis inductance can be reduced. Therefore, since the difference between the d-axis inductance and the q-axis inductance can be increased, the reluctance torque can be effectively used, and the output performance of the rotary electric machine can be improved.

(rib)
The pair of ribs 50 are provided so as to radially extend between the pair of inner diameter side arc magnets 820 and the gap portion 60 .

The pair of ribs 50 includes the first rib 51 radially extending between the d-axis side end 821D of the first inner diameter arc magnet 821 and the d-axis, and the d-axis side end of the second inner diameter arc magnet 822. and a second rib 52 extending radially between 822D and the d-axis.

The first rib 51 is composed of the d-axis side wall surface 421</b>D of the first inner diameter side magnet insertion hole 421 and the left side wall surface 61 of the gap 60 . The first rib 51 has a radially inner end portion 511 located radially inward and a radially outer end portion 512 located radially outwardly.

The second rib 52 is composed of the d-axis side wall surface 422</b>D of the second inner diameter side magnet insertion hole 422 and the right side wall surface 62 of the gap 60 . The second rib 52 has a radially inner end portion 521 located radially inward and a radially outer end portion 522 located radially outwardly.

Therefore, the first rib 51 receives the centrifugal load due to the first inner diameter arc magnet 821 , and the second rib 52 receives the centrifugal load due to the second inner diameter arc magnet 822 . That is, the first rib 51 and the second rib 52 separately receive the centrifugal load from the first inner diameter arc magnet 821 and the centrifugal load from the second inner diameter arc magnet 822 . Thereby, the bending stress generated in the rotor core 20 due to the weight variation of the first inner diameter arc magnet 821 and the second inner diameter arc magnet 822 can be reduced.

Furthermore, the first rib 51 and the second rib 52 are provided in a substantially V-shape so that the distance L5 in the circumferential direction between them increases toward the radially inner side. As a result, both the radially inner end portion 511 and the radially outer end portion 512 of the first rib 51 and the radially inner end portion 521 and the radially outer end portion 522 of the second rib 52 form the angle R. so that the radially inner end 511 and radially outer end 512 of the first rib 51 and the radially inner end 521 and radially outer end 522 of the second rib 52, i.e. the first Stress concentration on both radial ends of the rib 51 and the second rib 52 can be alleviated.

(hole)
A small-diameter first hole 261 is provided on the radially outer side of the first rib 51 . A small-diameter second hole 262 is provided on the radially outer side of the second rib 52 . In this embodiment, the first hole portion 261 and the second hole portion 262 are circular with the same diameter when viewed from the axial direction.

Therefore, the magnetic path through which the wraparound magnetic flux near the d-axis side end 821D of the first inner diameter arc magnet 821 passes and the magnetic path through which the wraparound magnetic flux near the d-axis side end 822D of the second inner diameter arc magnet 822 passes are: The magnetic resistance is increased by the first hole 261 and the second hole 262 . As a result, the wraparound magnetic flux near the d-axis end 821D of the first inner diameter arc magnet 821 and the wraparound magnetic flux near the d-axis end 822D of the second inner diameter arc magnet 822 can be reduced.

Furthermore, since the first hole portion 261 and the second hole portion 262 have circular shapes with the same diameter when viewed from the axial direction, the rotor core may It is possible to suppress the stress generated in 20 from concentrating around the first hole 261 and the second hole 262 .

(Manufacture of arc magnets)
Next, manufacturing of the outer diameter side arc magnet 810, the first inner diameter side arc magnet 821 and the second inner diameter side arc magnet 822 will be described with reference to FIG.

The outer diameter side arc magnet 810, the first inner diameter side arc magnet 821, and the second inner diameter side arc magnet 822 are formed by a ring magnet forming step of forming a substantially annular ring magnet precursor 900 and a heat treatment of the ring magnet precursor 900. and a heat treatment process for forming the ring magnet 910 and a cutting process for radially cutting the ring magnet 910 formed by the heat treatment process.

As shown in FIG. 3(a), a ring magnet precursor 900 is formed by hot working by hot extruding a ring magnet material in an extruder EM. By hot extrusion molding the ring magnet material, a radial compressive stress acts on the randomly oriented crystal group of the ring magnet material, and the crystal group of the ring magnet material is oriented in the same direction as the compressive stress direction. do. As a result, a radially oriented anisotropic ring magnet precursor 900 is formed.

In this embodiment, a ring magnet precursor 900 having an outer diameter r90 of approximately 80 mm and a thickness t90 of approximately 4.2 mm is formed.

Next, as shown in (b1) and (b2) of FIG. 3, the ring magnet precursor 900 is heat-treated to form a ring magnet 910 by a heat treatment step.

The heat treatment process includes a first heat treatment process shown in (b1) of FIG. 3 and a second heat treatment process shown in (b2) of FIG. 3 different from the first heat treatment process. In the heat treatment step, the ring magnet precursor 900 is heat treated by either the first heat treatment step or the second heat treatment step to form the ring magnet 910 . The ring magnet 910 changes its residual magnetic flux density and intrinsic coercive force depending on the heat treatment temperature and time.

In the first heat treatment step, the ring magnet precursor 900 is heat treated at a first predetermined temperature T1 for a first predetermined time P1. Thereby, the first ring magnet 911 is formed.

In the second heat treatment step, the ring magnet precursor 900 is heat treated at a second predetermined temperature T2 for a second predetermined time P2. Thereby, the second ring magnet 912 is formed.

In this embodiment, the first predetermined temperature T1 and the second predetermined temperature T2 are different temperatures. The first predetermined temperature T1 is higher than the second predetermined temperature T2.

As a result, the first ring magnet 911 has a higher residual magnetic flux density than the second ring magnet 912 . On the other hand, the second ring magnet 912 has a higher intrinsic coercive force than the first ring magnet 911 .

Next, as shown in (c1) and (c2) of FIG. 3, the ring magnet 910 is radially cut by a cutting step, and the outer diameter side arc magnet 810, the first inner diameter side arc magnet 821 and the second inner diameter side arc magnet 821 are cut. A side arc magnet 822 is manufactured.

As shown in (c1) of FIG. 3, the first ring magnet 911 is radially cut around the ring center C91 of the first ring magnet 911 at intervals of a predetermined angle φ1 in the circumferential direction.

As a result, the outer radius r10F is the outer diameter r90 of the ring magnet precursor 900, the thickness t10 is the thickness t90 of the ring magnet precursor 900, and the left end 810L and the right end 810L are arranged around the arc center C10. Outer diameter side circular arc magnet 810 having a predetermined angle φ1 with 810R is manufactured.

At this time, the predetermined angle φ1 is an angle that becomes 360 degrees when multiplied by an integer. For example, the predetermined angle φ1 is 12 degrees, 15 degrees, 18 degrees, 20 degrees, 24 degrees, 30 degrees, 36 degrees, 40 degrees, 60 degrees, and the like.

As a result, the outer diameter side arc magnet 810 can be manufactured from the first ring magnet 911 without generating a surplus, so the manufacturing cost of the outer diameter side arc magnet 810 can be reduced.

In this embodiment, the predetermined angle φ1 is 24 degrees. As a result, fifteen radially outer arc magnets 810 are manufactured from one first ring magnet 911 without any excess.

As shown in (c2) of FIG. 3, the second ring magnet 912 is radially cut around the ring center C92 of the second ring magnet 912 at intervals of a predetermined angle φ2 in the circumferential direction.

As a result, the outer radius r21F, r22F is the outer diameter r90 of the ring magnet precursor 900, the thickness t21, t22 is the thickness t90 of the ring magnet precursor 900, and the d-axis The first inner diameter arc magnet 821 and the second inner diameter arc magnet 822 are manufactured so that the angle formed by the side end portions 821D, 822D and the q-axis side end portions 821Q, 822Q is a predetermined angle φ2.

At this time, the predetermined angle φ2 is an angle that becomes 360 degrees when multiplied by an integer. For example, the predetermined angle φ2 is 12 degrees, 15 degrees, 18 degrees, 20 degrees, 24 degrees, 30 degrees, 36 degrees, 40 degrees, 60 degrees, and the like.

As a result, the first inner diameter side arc magnet 821 and the second inner diameter side arc magnet 822 can be manufactured from the second ring magnet 912 without generating a surplus. The manufacturing cost of the inner diameter arc magnet 822 can be reduced.

In this embodiment, the predetermined angle φ2 is 24 degrees. As a result, fifteen first inner diameter arc magnets 821 or second inner diameter arc magnets 822 are manufactured from one second ring magnet 912 without any excess.

In this embodiment, the predetermined angle φ1 and the predetermined angle φ2 are 24 degrees and are equal to each other. As a result, in the cutting step, the same cutting machine can be used to manufacture the outer diameter side arc magnet 810, the first inner diameter side arc magnet 821, and the second inner diameter side arc magnet 822. , the manufacturing cost of the first inner diameter arc magnet 821 and the second inner diameter arc magnet 822 can be reduced.

In this way, from the same ring magnet precursor 900 that has been formed into a substantially annular shape by the same extruder EM, the outer diameter side arc magnet 810, the first inner diameter side arc magnet 821 and the second inner diameter side arc magnet 822 are obtained. can be manufactured. Thereby, the manufacturing cost of the outer diameter side arc magnet 810, the first inner diameter side arc magnet 821, and the second inner diameter side arc magnet 822 can be reduced.

Since the first inner arc magnet 821 and the second inner arc magnet 822 are manufactured by cutting the second ring magnet 912, the outer diameter arc magnet 810 is manufactured by cutting the first ring magnet 911. Intrinsic coercive force is higher than As a result, demagnetization occurring in each region S of the first inner diameter arc magnet 821 and the second inner diameter arc magnet 822 through which interlinkage magnetic flux that does not pass through the outer diameter arc magnet 810 can be suppressed.

As shown in FIG. 4, the demagnetization index DM1 of the rotor 10 when using the same arc magnets as the outer diameter side arc magnet 810 for the first inner diameter side arc magnet 821 and the second inner diameter side arc magnet 822, The demagnetization index DM2 of the rotor 10 when arc magnets of the same shape and having a higher intrinsic coercive force than the outer diameter side arc magnet 810 are used for the first inner diameter side arc magnet 821 and the second inner diameter side arc magnet 822 is improved. do. In particular, the higher the temperature of the rotor 10 due to the driving of the rotor 10 or the like, the more significantly the demagnetization index DM2 improves with respect to the demagnetization index DM1.

On the other hand, since the outer diameter side arc magnet 810 is manufactured by cutting the first ring magnet 911, the first inner diameter side arc magnet 821 and the second inner diameter side arc magnet 821 are manufactured by cutting the second ring magnet 912. The residual magnetic flux density is higher than that of the arc magnet 822 . As a result, the magnet torque of the rotor 10 of the rotary electric machine can be increased while suppressing demagnetization occurring in each region S of the first inner diameter arc magnet 821 and the second inner diameter arc magnet 822 .

In this way, by subjecting the first inner arc magnet 821 and the second inner arc magnet 822 to a heat treatment different from the heat treatment of the outer arc magnet 810, the first inner arc magnet 821 and the second inner arc magnet 821 and the second inner arc magnet The intrinsic coercive force of arc magnet 822 can be easily made higher than the intrinsic coercive force of outer diameter side arc magnet 810 .

[Second embodiment]
Next, a rotor 10A for a rotary electric machine according to a second embodiment of the present invention will be described with reference to FIG. In the following description, the same components as those of the rotor 10 of the first embodiment are denoted by the same reference numerals, and the description thereof is omitted or simplified. Differences between the rotor 10 of the first embodiment and the rotor 10A of the second embodiment will be described in detail below.

In the heat treatment process of this embodiment, the first heat treatment process and the second heat treatment process are the same. That is, the first ring magnet 911 and the second ring magnet 912 have the same residual magnetic flux density and the same intrinsic coercive force.

Then, in the cutting step, the d-axis current is The coercive force increasing portion 823 is formed in the region S through which the interlinking magnetic flux that does not pass through the outer diameter arc magnet 810 passes among the interlinking magnetic fluxes caused by . The increased coercive force portion 823 has a higher intrinsic coercive force than the portions other than the increased coercive force portion 823 of the first inner diameter arc magnet 821 and the second inner diameter arc magnet 822 and the outer diameter arc magnet 810 .

The coercive force increasing portion 823 may be formed by any method. For example, the coercive force increasing portion 823 is formed by subjecting the region S including the q-axis side end portions 821Q and 822Q to grain boundary diffusion treatment.

As a result, the coercive force increasing portion 823 having a high intrinsic coercive force is provided in each region S of the first inner diameter side arc magnet 821 and the second inner diameter side arc magnet 822 through which the interlinking magnetic flux does not pass through the outer diameter side arc magnet 810. Thus, demagnetization occurring in each region S of the first inner diameter arc magnet 821 and the second inner diameter arc magnet 822 can be suppressed.

[Third Embodiment]
Next, a rotor 10B for a rotary electric machine according to a third embodiment of the present invention will be described with reference to FIG. In the following description, the same components as those of the rotor 10 of the first embodiment are denoted by the same reference numerals, and the description thereof is omitted or simplified. Differences between the rotor 10 of the first embodiment and the rotor 10B of the third embodiment will be described in detail below.

The first inner diameter arc magnet 821 of the present embodiment is adjacent to the d axis first inner diameter arc magnet 8211 arranged on the d axis side and the outer side of the d axis first inner diameter arc magnet 8211 in the circumferential direction. and the q-axis side first inner diameter side arc magnet 8212 arranged in the same direction. Similarly, the second inner diameter arc magnet 822 is adjacent to the d-axis second inner diameter arc magnet 8221 arranged on the d-axis side and the outer side of the second inner diameter arc magnet 8221 on the d-axis side in the circumferential direction. and the q-axis side second inner diameter side arc magnet 8222 arranged.

The q-axis first inner diameter arc magnet 8212 and the q-axis second inner diameter arc magnet 8222 define a region S through which the interlinkage flux that does not pass through the outer diameter arc magnet 810 out of the interlinkage magnetic flux generated by the d-axis current passes. contains. The q-axis first inner diameter arc magnet 8212 and the q-axis second inner diameter arc magnet 8222 are composed of the d-axis first inner diameter arc magnet 8211, the d-axis second inner diameter arc magnet 8221 and the outer diameter arc magnet. The intrinsic coercive force is higher than that of 810.

As a result, each region S of the first inner diameter arc magnet 821 and the second inner diameter arc magnet 822 through which the interlinking magnetic flux does not pass through the outer diameter arc magnet 810 is provided with a q-axis side first inner diameter magnet having a high intrinsic coercive force. Since the arc magnet 8212 and the q-axis second inner diameter arc magnet 8222 are arranged, demagnetization occurring in each region S of the first inner diameter arc magnet 821 and the second inner diameter arc magnet 822 can be suppressed.

The d-axis first inner diameter arc magnet 8211 and the d-axis second inner diameter arc magnet 8221 cut the first ring magnet 911 radially at intervals of, for example, 15 degrees in the circumferential direction around the ring center C91. manufactured by The q-axis first inner diameter arc magnet 8212 and the q-axis second inner diameter arc magnet 8222 cut the second ring magnet 912 radially at intervals of, for example, 9 degrees in the circumferential direction around the ring center C92. manufactured by

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and can be modified, improved, and the like as appropriate.

For example, in the first embodiment, in the heat treatment step, the ring magnet precursor 900 is heat-treated by either the first heat treatment step or the second heat treatment step different from the first heat treatment step, thereby increasing the intrinsic retention. A first ring magnet 911 and a second ring magnet 912 having different magnetic forces are formed, and an outer diameter side arc magnet 810 and a first inner diameter side arc magnet 821 and a second The inner diameter side arc magnet 822 is manufactured, but by manufacturing the first inner diameter side arc magnet 821 and the second inner diameter side arc magnet 822 with a material different from the outer diameter side arc magnet 810 The side arc magnet 810 and the first inner diameter side arc magnet 821 and the second inner diameter side arc magnet 822 having higher intrinsic coercive force than the outer diameter side arc magnet 810 may be manufactured. Different materials may be made of different raw materials, or may be made of the same raw material but have different composition ratios and component ratios. Thereby, the intrinsic coercive force of the first inner diameter arc magnet 821 and the second inner diameter arc magnet 822 can be easily made higher than the intrinsic coercive force of the outer diameter arc magnet 810 .

In addition, at least the following matters are described in this specification. In addition, although the parenthesis shows the components corresponding to the above-described embodiment, the present invention is not limited to this.

(1) A substantially annular rotor core (rotor core 20);
a plurality of magnetic pole portions (magnetic pole portions 30) formed at predetermined intervals in the circumferential direction of the rotor core,
Each magnetic pole is
an outer diameter side magnet portion (outer diameter side magnet portion 310) composed of at least one outer diameter side arc magnet (outer diameter side arc magnet 810) arranged so as to protrude radially inward;
An inner diameter composed of at least a pair of inner-diameter-side arc magnets (inner-diameter-side arc magnets 820) located radially inward of the outer-diameter-side magnet portion and arranged so as to protrude inward in the radial direction a side magnet portion (inner diameter side magnet portion 320),
Each arc magnet is an arc magnet in which the inner peripheral surface and the outer peripheral surface have the same arc center,
When the central axis of each magnetic pole portion is the d-axis and the axis separated by an electrical angle of 90 degrees from the d-axis is the q-axis,
The inner diameter side magnet portion is formed symmetrically with respect to the d-axis,
The pair of inner diameter arc magnets are
Positioned on one side (left side) of the d-axis in the circumferential direction, the d-axis side end (d-axis side end 821D) on the d-axis side and the q-axis side end (q-axis side) on the q-axis side (q a first inner diameter arc magnet (first inner diameter arc magnet 821) having an axial end portion 821Q;
Positioned on the other side (right side) of the d-axis in the circumferential direction, the d-axis side end (d-axis side end 822D) on the d-axis side and the q-axis side end (q-axis side) on the q-axis side (q A rotor (rotor 10) of a rotary electric machine, comprising:
The outer diameter arc magnet, the first inner diameter arc magnet, and the second inner diameter arc magnet have substantially the same shape when viewed from the axial direction,
The q-axis side end of the first inner diameter arc magnet is located on the one side of the outer diameter arc magnet in the circumferential direction of the arc center (arc center C10) of the outer diameter arc magnet. The first end (left end 810L) and the first imaginary straight line (first imaginary straight line VL1) passing therethrough are arranged so as to be outside in the circumferential direction,
The q-axis side end of the second inner diameter arc magnet is a second end located on the other side in the circumferential direction of the outer diameter arc magnet and the arc center of the outer diameter arc magnet. (right end portion 810R) and a second imaginary straight line (second imaginary straight line VL2) passing through the second imaginary straight line VL2 in the circumferential direction,
A rotor of a rotary electric machine, wherein the first inner diameter arc magnet and the second inner diameter arc magnet have a higher intrinsic coercive force than the outer diameter arc magnet.

According to (1), the first inner diameter arc magnet is arranged such that the q-axis side end is outside the first imaginary straight line in the circumferential direction, and the second inner diameter arc magnet is arranged along the q axis. The side ends are arranged so as to be outside the second imaginary straight line in the circumferential direction. Outside the first imaginary straight line of the first inner diameter arc magnet in the circumferential direction and outside the second imaginary straight line of the second inner diameter arc magnet in the circumferential direction A region is formed through which interlinkage magnetic flux that does not pass through the radial arc magnet passes. Each area of the first inner arc magnet and the second inner arc magnet through which the interlinking magnetic flux that does not pass through the outer arc magnet has a low permeance is easily demagnetized.
Since the first inner arc magnet and the second inner arc magnet have a higher intrinsic coercive force than the outer arc magnet, the interlinking magnetic flux that does not pass through the outer arc magnet passes through the first inner arc magnet and the second inner arc magnet. 2. It is possible to suppress the demagnetization that occurs in each area of the inner diameter arc magnet.
Furthermore, since the outer diameter side arc magnet, the first inner diameter side arc magnet, and the second inner diameter side arc magnet have substantially the same shape when viewed from the axial direction, they are molded into a substantially annular shape by the same molding machine. Outer-diameter-side arc magnets, first inner-diameter-side arc magnets, and second inner-diameter-side arc magnets can be manufactured from the ring magnet thus obtained. Thereby, the manufacturing cost of the outer diameter side arc magnet, the first inner diameter side arc magnet, and the second inner diameter side arc magnet can be reduced.

(2) The rotor of the rotary electric machine according to (1),
A rotor of a rotary electric machine, wherein the outer diameter arc magnet has a higher residual magnetic flux density than the first inner diameter arc magnet and the second inner diameter arc magnet.

According to (2), since the outer diameter arc magnet has a higher residual magnetic flux density than the first inner diameter arc magnet and the second inner diameter arc magnet, the first inner diameter arc magnet and the second inner diameter arc magnet It is possible to increase the magnet torque of the rotor of the rotary electric machine while suppressing the demagnetization that occurs.

(3) The rotor of the rotary electric machine according to (1) or (2),
A rotor of a rotary electric machine, wherein the first inner diameter arc magnet and the second inner diameter arc magnet are permanent magnets made of a material different from that of the outer diameter arc magnet.

According to (3), permanent magnets made of a material different from that of the outer arc magnet are used for the first inner arc magnet and the second inner arc magnet, so that the first inner arc magnet and the second inner arc magnet The intrinsic coercive force of the arc magnet can be easily made higher than the intrinsic coercive force of the outer diameter side arc magnet.

(4) The rotor of the rotary electric machine according to (1) or (2),
A rotor of a rotary electric machine, wherein the first inner diameter arc magnet and the second inner diameter arc magnet are permanent magnets that have undergone a heat treatment different from that of the outer diameter arc magnet.

According to (4), by subjecting the first inner arc magnet and the second inner arc magnet to a heat treatment different from the heat treatment of the outer diameter arc magnet, the first inner arc magnet and the second inner arc magnet The intrinsic coercive force of the magnet can be easily made higher than the intrinsic coercive force of the outer diameter arc magnet.

(5) An arc magnet manufacturing method for manufacturing each arc magnet of the rotor of the rotary electric machine according to (1) or (2),
a ring magnet forming step of forming a substantially annular ring magnet precursor (ring magnet precursor 900);
a heat treatment step of heat-treating the ring magnet precursor to form a ring magnet (ring magnet 910);
a cutting step of radially cutting the ring magnet formed by the heat treatment step;
In the ring magnet forming step, the ring magnet precursor is formed by hot working,
The heat treatment step includes a first heat treatment step and a second heat treatment step different from the first heat treatment step,
In the heat treatment step, the ring magnet precursor is heat treated by either one of the first heat treatment step and the second heat treatment step, and the first ring magnet (first ring magnet 911) heat-treated by the first heat treatment step. and a second ring magnet (second ring magnet 912) heat-treated in the second heat treatment step,
In the cutting step,
By cutting the first ring magnet radially at intervals of a predetermined angle (predetermined angle φ1) in the circumferential direction around the ring center (ring center C91) of the first ring magnet, the outer diameter side arc manufacture magnets,
By cutting the second ring magnet radially at intervals of a predetermined angle (predetermined angle φ2) in the circumferential direction around the ring center (ring center C92) of the second ring magnet, the first inner diameter side An arc magnet manufacturing method for manufacturing the arc magnet and the second inner diameter side arc magnet.

According to (5), in the heat treatment step, the ring magnet precursor is heat-treated by either the first heat treatment step or the second heat treatment step, and the first ring magnet heat-treated by the first heat treatment step and the second heat treatment A second ring magnet heat-treated by the step is formed, and in the cutting step, the first ring magnet is cut in the radial direction to produce the outer diameter arc magnet, and the second ring magnet is cut in the radial direction. By doing so, the first inner arc magnet and the second inner arc magnet can be manufactured from the same ring magnet precursor. Side arc magnets can be manufactured. Thereby, the manufacturing cost of the outer diameter side arc magnet, the first inner diameter side arc magnet, and the second inner diameter side arc magnet can be reduced.

(6) a substantially annular rotor core (rotor core 20);
a plurality of magnetic pole portions (magnetic pole portions 30) formed at predetermined intervals in the circumferential direction of the rotor core,
Each magnetic pole is
an outer diameter side magnet portion (outer diameter side magnet portion 310) composed of at least one outer diameter side arc magnet (outer diameter side arc magnet 810) arranged so as to protrude radially inward;
An inner diameter composed of at least a pair of inner-diameter-side arc magnets (inner-diameter-side arc magnets 820) located radially inward of the outer-diameter-side magnet portion and arranged so as to protrude inward in the radial direction a side magnet portion (inner diameter side magnet portion 320),
Each arc magnet is an arc magnet in which the inner peripheral surface and the outer peripheral surface have the same arc center,
When the central axis of each magnetic pole portion is the d-axis and the axis separated by an electrical angle of 90 degrees from the d-axis is the q-axis,
The inner diameter side magnet portion is formed symmetrically with respect to the d-axis,
The pair of inner diameter arc magnets are
Positioned on one side (left side) of the d-axis in the circumferential direction, the d-axis side end (d-axis side end 821D) on the d-axis side and the q-axis side end (q-axis side) on the q-axis side (q a first inner diameter arc magnet (first inner diameter arc magnet 821) having an axial end 821Q;
Positioned on the other side (right side) of the d-axis in the circumferential direction, the d-axis side end (d-axis side end 822D) on the d-axis side and the q-axis side end (q-axis side) on the q-axis side (q A rotor (rotor 10) of a rotary electric machine, comprising:
The outer diameter arc magnet, the first inner diameter arc magnet, and the second inner diameter arc magnet have substantially the same shape when viewed from the axial direction,
The q-axis side end of the first inner diameter arc magnet is located on the one side of the outer diameter arc magnet in the circumferential direction of the arc center (arc center C10) of the outer diameter arc magnet. A first imaginary straight line (first imaginary straight line VL1) passing through a first end (left end 810L) is located outside in the circumferential direction, and the d-axis side end is located further than the first imaginary straight line. arranged to be inner in the circumferential direction,
The q-axis side end of the second inner diameter arc magnet is a second end located on the other side in the circumferential direction of the outer diameter arc magnet and the arc center of the outer diameter arc magnet. (Right end portion 810R) and a second imaginary straight line (second imaginary straight line VL2) passing through the d-axis side end portion in the circumferential direction. arranged to be inside,
The first inner diameter arc magnet has an intrinsic coercive force greater than that of the outer diameter arc magnet in a region (region S) that includes the q-axis side end and is outside the first imaginary straight line in the circumferential direction (region S). A coercive force increased portion (coercive force increased portion 823) is formed with a high
In the second inner diameter arc magnet, an intrinsic coercive force greater than that of the outer diameter arc magnet is provided in a region (region S) that includes the q-axis side end and is outside the second imaginary straight line in the circumferential direction (region S). A rotor of a rotary electric machine in which a coercive force increased portion (coercive force increased portion 823) having a high coercive force is formed.

According to (6), the first inner-diameter-side arc magnet has a q-axis side end outside the first imaginary straight line in the circumferential direction, and a d-axis side end inside the first imaginary straight line in the circumferential direction. The second inner diameter arc magnet has a q-axis side end located outside the second imaginary straight line in the circumferential direction, and a d-axis side end located circumferentially outside the second imaginary straight line is arranged to be inside at Outside the first imaginary straight line of the first inner diameter arc magnet in the circumferential direction and outside the second imaginary straight line of the second inner diameter arc magnet in the circumferential direction A region is formed through which interlinkage magnetic flux that does not pass through the radial arc magnet passes. Each area of the first inner arc magnet and the second inner arc magnet through which the interlinking magnetic flux that does not pass through the outer arc magnet has a low permeance is easily demagnetized.
A coercive force increasing portion having a higher intrinsic coercive force than that of the outer diameter arc magnet is formed in a region of the first inner diameter arc magnet, which includes the q-axis side end and is outside the first imaginary straight line in the circumferential direction. In the second inner diameter arc magnet, a coercive force increasing portion having a higher intrinsic coercive force than the outer diameter arc magnet is provided in a region outside the second imaginary straight line in the circumferential direction, including the q-axis side end. is formed. As a result, the coercive force increasing portion having a high intrinsic coercive force can be provided in each region of the first inner diameter arc magnet and the second inner diameter arc magnet through which the interlinking magnetic flux does not pass through the outer diameter arc magnet. It is possible to suppress demagnetization occurring in each region of the first inner diameter arc magnet and the second inner diameter arc magnet through which interlinkage magnetic flux that does not pass through the diameter arc magnet passes.

10 rotor 20 rotor core 30 magnetic pole portion 310 outer diameter side magnet portion 320 inner diameter side magnet portion 810 outer diameter side arc magnet 810L left end (first end)
810R right end (second end)
820 inner diameter arc magnet 821 first inner diameter arc magnet 821D d-axis end 821Q q-axis end 822 second inner diameter arc magnet 822D d-axis end 822Q q-axis end 823 coercive force increasing portion 900 ring Magnet precursor 910 Ring magnet 911 First ring magnet 912 Second ring magnet C10 Arc center C91 Ring center C92 Ring center S Area VL1 First virtual straight line VL2 Second virtual straight lines φ1, φ2 Predetermined angle

Claims (6)

a substantially annular rotor core;
a plurality of magnetic pole portions formed at predetermined intervals in the circumferential direction of the rotor core,
Each magnetic pole is
an outer diameter side magnet portion composed of at least one outer diameter side arc magnet arranged so as to protrude radially inward;
an inner diameter side magnet portion positioned radially inward of the outer diameter side magnet portion and configured from at least a pair of inner diameter side arc magnets arranged so as to protrude inward in the radial direction. death,
Each arc magnet is an arc magnet in which the inner peripheral surface and the outer peripheral surface have the same arc center,
When the central axis of each magnetic pole portion is the d-axis and the axis separated by an electrical angle of 90 degrees from the d-axis is the q-axis,
The inner diameter side magnet portion is formed symmetrically with respect to the d-axis,
The pair of inner diameter arc magnets are
a first inner diameter arc magnet located on one side of the d-axis in the circumferential direction and having a d-axis side end on the d-axis side and a q-axis side end on the q-axis side;
a second inner diameter arc magnet located on the other side of the d-axis in the circumferential direction and having a d-axis side end on the d-axis side and a q-axis side end on the q-axis side; A rotor of a rotating electric machine,
The outer diameter arc magnet, the first inner diameter arc magnet, and the second inner diameter arc magnet have substantially the same shape when viewed from the axial direction,
The q-axis side end of the first inner diameter arc magnet is positioned between the center of the arc of the outer diameter arc magnet and the first end located on the one side in the circumferential direction of the outer diameter arc magnet. is arranged to be outside in the circumferential direction from the first imaginary straight line passing through,
The q-axis side end of the second inner diameter arc magnet is a second end located on the other side in the circumferential direction of the outer diameter arc magnet and the arc center of the outer diameter arc magnet. and arranged so as to be outside in the circumferential direction of the second imaginary straight line passing through,
A rotor of a rotary electric machine, wherein the first inner diameter arc magnet and the second inner diameter arc magnet have a higher intrinsic coercive force than the outer diameter arc magnet. The rotor of the rotary electric machine according to claim 1,
A rotor of a rotary electric machine, wherein the outer diameter arc magnet has a higher residual magnetic flux density than the first inner diameter arc magnet and the second inner diameter arc magnet. 3. The rotor of the rotary electric machine according to claim 1,
A rotor of a rotary electric machine, wherein the first inner diameter arc magnet and the second inner diameter arc magnet are permanent magnets made of a material different from that of the outer diameter arc magnet. 3. The rotor of the rotary electric machine according to claim 1,
A rotor of a rotary electric machine, wherein the first inner diameter arc magnet and the second inner diameter arc magnet are permanent magnets that have undergone a heat treatment different from that of the outer diameter arc magnet. An arc magnet manufacturing method for manufacturing each arc magnet of the rotor of the rotary electric machine according to claim 1 or 2,
a ring magnet forming step of forming a substantially annular ring magnet precursor;
a heat treatment step of heat-treating the ring magnet precursor to form a ring magnet;
a cutting step of radially cutting the ring magnet formed by the heat treatment step;
In the ring magnet forming step, the ring magnet precursor is formed by hot working,
The heat treatment step includes a first heat treatment step and a second heat treatment step different from the first heat treatment step,
In the heat treatment step, the ring magnet precursor is heat-treated by either one of the first heat treatment step and the second heat treatment step, and the first ring magnet heat-treated by the first heat treatment step and the second heat treatment step a second ring magnet heat-treated by
In the cutting step,
manufacturing the outer diameter side arc magnet by cutting the first ring magnet radially at predetermined angular intervals in the circumferential direction around the center of the ring of the first ring magnet;
The first inner arc magnet and the second inner arc magnet are obtained by radially cutting the second ring magnet at predetermined angular intervals in the circumferential direction around the center of the ring of the second ring magnet. A method for manufacturing an arc magnet. a substantially annular rotor core;
a plurality of magnetic pole portions formed at predetermined intervals in the circumferential direction of the rotor core,
Each magnetic pole is
an outer diameter side magnet portion composed of at least one outer diameter side arc magnet arranged so as to protrude radially inward;
an inner diameter side magnet portion positioned radially inward of the outer diameter side magnet portion and configured from at least a pair of inner diameter side arc magnets arranged so as to protrude inward in the radial direction. death,
Each arc magnet is an arc magnet in which the inner peripheral surface and the outer peripheral surface have the same arc center,
When the central axis of each magnetic pole portion is the d-axis and the axis separated by an electrical angle of 90 degrees from the d-axis is the q-axis,
The inner diameter side magnet portion is formed symmetrically with respect to the d-axis,
The pair of inner diameter arc magnets are
a first inner diameter arc magnet located on one side of the d-axis in the circumferential direction and having a d-axis side end on the d-axis side and a q-axis side end on the q-axis side;
a second inner diameter arc magnet located on the other side of the d-axis in the circumferential direction and having a d-axis side end on the d-axis side and a q-axis side end on the q-axis side; A rotor of a rotating electric machine,
The outer diameter arc magnet, the first inner diameter arc magnet, and the second inner diameter arc magnet have substantially the same shape when viewed from the axial direction,
The q-axis side end of the first inner diameter arc magnet is positioned between the center of the arc of the outer diameter arc magnet and the first end located on the one side in the circumferential direction of the outer diameter arc magnet. , and the d-axis side end portion is arranged to be inner than the first imaginary line in the circumferential direction,
The q-axis side end of the second inner diameter arc magnet is a second end located on the other side in the circumferential direction of the outer diameter arc magnet and the arc center of the outer diameter arc magnet. and the d-axis side end is arranged to be inner than the second imaginary line in the circumferential direction, and
In the first inner diameter arc magnet, a coercive force having a higher intrinsic coercive force than that of the outer diameter arc magnet is provided in a region including the q-axis side end and outside the first imaginary straight line in the circumferential direction. An enlarged part is formed,
In the second inner diameter arc magnet, a coercive force having a higher intrinsic coercive force than that of the outer diameter arc magnet is provided in a region including the q-axis side end portion and outside the second imaginary straight line in the circumferential direction. A rotor of a rotary electric machine, in which an enlarged portion is formed.

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