JP2022036348A - Electric machine - Google Patents

Abstract

To provide an electric machine capable of reducing torque ripple in a case where two magnetic poles having different poles on an armature side are adjacent to each other in a movement direction on a permanent magnet embedded in a field core.SOLUTION: An electric machine 200 comprises: an armature 3; and a magnetic field 2 that faces the armature 3 via a gap 1 and disposed so as to be relatively movable to the armature 3, the magnetic field 2 having a permanent magnet 50 formed with magnetic poles 51, 52 with different poles on the armature 3 side being adjacent to each other in a movement direction, and a magnetic field iron core 15 in which the permanent magnet 50 is embedded. In an armature side magnetic field iron core part 22 as a magnetic field iron core positioned at the armature 3 side with respect to the permanent magnet 50, a hole part 11 which is recessed toward the permanent magnet 50 from a virtual surface 90 apart in a direction toward the magnetic field iron core 15 at a distance equal to the minimum length of the gap 1 from the armature 3, is formed at a position on an adjacent surface 24 including a surface on which the magnetic poles 51, 52 are adjacent to each other.SELECTED DRAWING: Figure 3

Description

The present invention relates to an electric machine having a field magnet in which a permanent magnet is embedded.

A conventional electric machine has a stator which is an armature, a permanent magnet in which a plurality of magnetic poles are formed, and a field iron core, and moves toward the stator through a gap and moves relative to the stator. It is equipped with a mover that is a field magnet. A technique is known in which the number of permanent magnets is reduced, the manufacturing cost is reduced by reducing the man-hours for manufacturing the permanent magnets, and the torque is improved by this configuration (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2006-288183

In Patent Document 1, a permanent magnet is embedded in a field iron core in a rotor, which is a mover of a rotary electric machine. Each permanent magnet is inserted into a magnet insertion hole formed in a field iron core. This rotary electric machine is called an embedded magnet type (Interior Permanent Magnet) rotary electric machine. Even if the permanent magnet is damaged, it is possible to prevent the fragments of the permanent magnet from staying in the magnet insertion hole of the field iron core and moving to the gap between the rotor and the stator.
Further, in one permanent magnet, two magnetic poles having different poles on the stator side are adjacent to each other in the moving direction. A flux barrier is provided at a position along the adjacent surface between adjacent magnetic poles in the field core on the stator side of the permanent magnet, and the outer peripheral portion of the field core on the stator side of the permanent magnet is connected. ing. With this configuration, it becomes difficult for the magnetic flux that short-circuits the magnetic poles to pass through, and the torque generated by the rotary electric machine increases.

However, depending on the magnitude of the current applied to the stator, the outer circumference of the field iron core on the stator side of the permanent magnet may not be magnetically saturated. When the outer circumference of the field core is not magnetically saturated, the magnetic flux between adjacent magnetic poles is short-circuited through the outer circumference of the field core, so that there is a problem that torque ripple, which is a pulsation of torque, increases.

The present invention has been made to solve the above-mentioned problems, and is a case where two magnetic poles having different poles on the armature side of a permanent magnet embedded in a field iron core are adjacent to each other in the moving direction. In addition, it is an object of the present invention to obtain an electric machine that reduces torque ripple as compared with the case where the outer periphery of the field iron core on the armature side of the permanent magnet is connected.

The electric machine according to the present invention is
With an armature
A field that faces the armature through a gap and is movably arranged relative to the armature, and is a permanent magnet formed by magnetic poles having different poles on the armature side adjacent to each other in the moving direction. Equipped with a magnet, and a field with a field iron core in which a permanent magnet is embedded,
When a surface separated from the armature in the direction toward the field core at a distance equal to the minimum length of the void is used as a virtual surface.
In the field core of the armature, which is the field core located on the armature side of the permanent magnet, the hole recessed from the virtual surface toward the permanent magnet is the position of the adjacent surface including the surface where the magnetic poles are adjacent to each other. It is formed in.

In an electric machine configured as described above, when two magnetic poles having different poles on the armature side of a permanent magnet embedded in a field iron core are adjacent to each other in the moving direction, the armature side is closer to the armature side than the permanent magnet. The torque ripple can be reduced as compared with the case where the outer circumferences of the field iron cores in the above are connected.

It is a figure of the drive system in Embodiment 1 of this invention. FIG. 1 is a sectional view taken along the line AA of FIG. 1 of the electric machine according to the first embodiment of the present invention. It is a partial cross-sectional view of the electric machine in Embodiment 1 of this invention. It is a figure which shows the waveform of the magnetic flux density of the void of the electric machine in Embodiment 1 of this invention. It is a partial cross-sectional view of the first comparative example of the electric machine in Embodiment 1 of this invention. It is a figure which shows the waveform of the magnetic flux density of the void in the 1st comparative example of the electric machine in Embodiment 1 of this invention. It is a figure which shows the 6f component of the torque ripple in the electric machine in Embodiment 1 of this invention, and the electric machine of 1st comparative example. It is a partial sectional view of the 1st modification of the electric machine in Embodiment 1 of this invention. FIG. 3 is a sectional view taken along the line AA of FIG. 1 in a rotor of a second modification of the electric machine according to the second embodiment of the present invention. It is a partial sectional view of the 2nd modification of the electric machine in Embodiment 2 of this invention. It is a partial sectional view of the 3rd modification of the electric machine in Embodiment 3 of this invention. It is a partial cross-sectional view of the 4th modification of the electric machine in Embodiment 3 of this invention. It is a partial sectional view of the 5th modification of the electric machine in Embodiment 3 of this invention. It is a partial cross-sectional view of the sixth modification of the electric machine in Embodiment 3 of this invention. It is a partial cross-sectional view of the 7th modification of the electric machine in Embodiment 4 of this invention. It is a partial cross-sectional view of the 8th modification of the electric machine in Embodiment 5 of this invention. It is a perspective view of the rotor of the 9th modification of the electric machine in Embodiment 6 of this invention. FIG. 6 is a sectional view taken along line GG of FIG. 17 of a ninth modification of the electric machine according to the sixth embodiment of the present invention. It is a perspective view of the rotor of the tenth modification of the electric machine in Embodiment 6 of this invention. It is a partial cross-sectional view of the eleventh modification of the electric machine in Embodiment 7 of this invention. It is a partial cross-sectional view of the twelfth modification of the electric machine in Embodiment 7 of this invention.

Hereinafter, embodiments suitable for carrying out the present invention will be described with reference to the drawings.
Embodiment 1.
FIG. 1 is a diagram of a drive system according to the first embodiment for carrying out the present invention. In FIG. 1, the drive system 500 includes a rotary electric machine 200, which is an electric machine, and an inverter 100. The rotary electric machine 200 and the inverter 100 are electrically connected, and a three-phase alternating current is energized from the inverter 100 to the rotary electric machine 200. The figure of the rotary electric machine 200 in FIG. 1 is shown as a side sectional view which is a cross-sectional view in a plane including the rotation axis of the rotary electric machine 200. Hereinafter, the axis of rotation is referred to as an axis.

In FIG. 1, the rotary electric machine 200 according to the present embodiment includes a stator 3 which is an armature and a rotor 2 which is a field magnet. The rotor 2 is fixed to the outer peripheral surface of the support shaft 4. Two bearings 5 are fitted to both ends of the support shaft 4 in the axial direction and on the outer peripheral surfaces of the rotor 2 on both ends in the axial direction. The outer peripheral surface of each of the two bearings 5 is fitted to the inner peripheral surface of the housing 9 and held in the housing 9. The outer peripheral surface of the stator 3 is fitted and fixed to the inner peripheral surface of the housing 9. With these configurations, the rotor 2 rotates about the axis of the support shaft 4. That is, the rotor 2 is arranged so as to face the stator 3 via the gap 1 and to be relatively movable with respect to the stator 3, that is, to be rotatable.

FIG. 2 is a sectional view taken along the line AA of FIG. 1 of the electric machine according to the present embodiment. The cross-sectional view is a cross-sectional view in a plane orthogonal to the rotation axis of the rotary electric machine 200 which is an electric machine. In FIG. 2, the stator 3 includes a stator core 16 which is an armature core, 12 windings 6, and 12 insulators 8. The stator core 16 has an annular core back portion 17 and twelve teeth portions 18 projecting from the core back portion 17 toward the rotor 2 and arranging at equal intervals in the rotation direction, that is, the circumferential direction, which is the movement direction. .. The stator core 16 is configured by laminating a plurality of sheet-shaped stator core sheets 16-1 punched from an electromagnetic steel sheet in the same shape in an axial direction at a predetermined length for the purpose of reducing eddy current. There is. The tooth portion 18 of the stator core 16 is arranged so as to face the rotor 2 via the gap 1. Twelve slots 21 are formed between the tooth portions 18 adjacent to each other in the circumferential direction. The twelve windings 6 are each wound around the teeth portion 18 via the insulator 8 and housed in each of the twelve slots 21. The winding 6 is composed of 12 windings 6 in total, with 4 windings 6 per phase for 3 phases. Four windings 6 per phase are connected in series to form a phase winding group, and the phase winding groups for three phases are Y-connected. A rotating magnetic field that rotates in the circumferential direction is a stator by energizing each phase winding group having windings 6 from an inverter 100, which is a power converter, with a phase shift between the three phases of alternating current by 120 °. It is generated from 3 to the void 1 and a torque is generated in the rotor 2. The connection method of the three-phase winding group is not limited to the Y connection and may be a Δ connection.

The rotor 2 has four permanent magnets 50 and a rotor core 15 which is a field core in which four permanent magnets 50 are embedded. The rotor core 15 is configured by laminating a plurality of sheet-shaped rotor core sheets 15-1 punched from an electromagnetic steel sheet in the same shape in the axial direction to a predetermined length. In the rotor core 15, four magnet insertion holes 19 into which the permanent magnets 50 are inserted are formed at equal intervals in the circumferential direction, which is the same number as the permanent magnets 50. One permanent magnet 50 is inserted into each of the four magnet insertion holes 19.

At both ends of the magnet insertion hole 19 in the circumferential direction, a flux barrier 7 which is a hole penetrating in the axial direction suppresses a short circuit of magnetic flux between the permanent magnets 50 inserted in the magnet insertion holes 19 adjacent to each other in the circumferential direction. It is provided. A non-magnetic material such as a resin may be inserted into the flux barrier 7.

The permanent magnet 50 is formed so that the magnetic poles 51 and 52 having different poles on the armature 3 side are adjacent to each other in the rotation direction, that is, the circumferential direction, which is the movement direction. That is, in FIG. 1, the magnetic pole 51 is magnetized so as to have an N pole on the surface on the stator 3 side, and the magnetic pole 52 has an S pole on the surface on the stator 3 side. The north pole of the magnetic pole 51 is formed on the surface on the stator 3 side on one side in the circumferential direction from the central portion of the permanent magnet 50, that is, the outer surface in the radial direction. The pole of the S pole of the magnetic pole 52 is formed on the surface on the stator 3 side on the other side in the circumferential direction from the central portion of the permanent magnet 50, that is, the outer surface in the radial direction. The surface where the magnetic poles 51 and 52 are adjacent to each other in the circumferential direction is the magnetic pole boundary 10.
In FIG. 2, since the total number of magnetic poles 51 and 52 appearing in the gap 1 is eight in the rotary electric machine 200, the number of magnetic poles 51 and 52 is eight and the number of slots 21 is twelve. There is.

The permanent magnet 50 has a flat plate shape. That is, the permanent magnet 50 has two planes facing each other, and the surface of the permanent magnet 50 on the stator 3 side on which the magnetic poles 51 and 52 are formed is one plane. In FIG. 2, the cross-sectional shape of the permanent magnet 50 in the cross section including the radial direction and the circumferential direction, which are the directions from the permanent magnet 50 toward the stator 3, is rectangular. The cross section including the radial direction and the circumferential direction is a cross section orthogonal to the axial direction. The permanent magnet 50 is elongated in the axial direction with a cross-sectional shape orthogonal to the same axial direction. In FIG. 2, the axial length of the permanent magnet 50 is equal to the axial length of the rotor core 15. The axial length of the permanent magnet 50 may be different from the axial length of the rotor core 15.
Since the permanent magnet 50 has a flat plate shape, the man-hours for shaping the permanent magnet 50 can be reduced as compared with the case where the permanent magnet has a curved surface shape.

The magnetic pole 51 and the magnetic pole 52 may be configured as separate segment magnets, that is, magnetic bodies that are separate permanent magnet pieces. That is, the permanent magnet 50 may be composed of a plurality of magnetic materials divided for each of the magnetic poles 51 and 52. In the case of FIG. 2, the permanent magnet 50 may be composed of two magnetic materials divided into magnetic poles 51 and 52. With this configuration, each magnetic material of the permanent magnet piece can be magnetized to form a magnetic pole for each magnetic material. Therefore, it is possible to improve the magnetizing rate, which is the ratio of the magnetic flux generated by the permanent magnet piece after magnetization to the magnetic flux generated by the permanent magnet piece in the completely magnetized state.

Further, magnetizing is performed on a magnetic material which is one permanent magnet piece which is an integral segment magnet, and magnetic poles 51 and 52 having different poles on the stator 3 side of the permanent magnet 50 are arranged in the circumferential direction. It may be formed adjacent to each other. That is, the permanent magnet 50 may be composed of one magnetic material having a plurality of magnetic poles 51 and 52. With this configuration, it is possible to reduce the cost related to the control points, the processing man-hours, and the magnetizing man-hours of the permanent magnet 50.

In FIG. 2, when the permanent magnet 50 is composed of two magnetic bodies on which the magnetic poles 51 and 52 are formed, the two magnetic bodies are adjacent to each other in the circumferential direction at the magnetic pole boundary 10. It becomes a face. Further, when the permanent magnet 50 is composed of one magnetic material, the magnetic pole boundary 10 is a circumferential position where the pole is switched from N pole to S pole or from S pole to N pole, that is, a circumference without a pole. It becomes the surface of the directional position. Further, when the permanent magnet 50 is composed of one magnetic material, there is a region in the circumferential direction where there is no pole at the circumferential end of the magnetic poles 51 and 52 on the side where the magnetic poles 51 and 52 are adjacent to each other in the circumferential direction. If so, the magnetic pole boundary 10 is a surface located at the center of the circumferential range of the region without poles.

Further, an arbitrary number of magnetic poles 51 and 52 having two or more poles may be magnetized to the permanent magnet 50. That is, the number of magnetic poles 51 and 52 in the permanent magnet 50 may be three or more.

FIG. 3 is a partial cross-sectional view of an electric machine according to the present embodiment. In FIG. 3, the rotor core 15 located on the stator 3 side of the permanent magnet 50 is referred to as the armature side field core portion 22. A surface separated from the stator 3 in the direction toward the rotor core 15 at a distance equal to the minimum length g of the void 1 is referred to as a virtual surface 90. The surface including the magnetic pole boundary 10, which is the surface on which the magnetic poles 51 and 52 are adjacent to each other, is referred to as an adjacent surface 24. In the armature side field iron core portion 22, a hole portion 11 recessed from the virtual surface 90 toward the permanent magnet 50 is formed at the position of the adjacent surface 24. Here, the minimum length g of the void 1 represents the minimum distance in the radial direction between the tooth portion 18 of the stator core 16 and the rotor core 15. The boundary of the armature-side field core portion 22 is a portion of the rotor core 15 having a minimum width tb in the direction from the circumferential end of the permanent magnet 50 toward the stator 3. In FIG. 3, the virtual surface 90 is a cylindrical surface separated from the stator 3 in the direction toward the rotor core 15 with the minimum length g of the gap 1 set.

The hole portion 11 is formed in the armature side field iron core portion 22 so as to straddle the adjacent surface 24 in the circumferential direction. The cross-sectional shape of the hole 11 in the cross section perpendicular to the axial direction is a wedge shape in which the width in the moving direction narrows in the direction from the virtual surface 90 toward the permanent magnet 50 side and becomes convex.

In FIG. 3, in the circumferential range occupied by the hole portion 11, the permanent magnet 50 in the armature side field magnetic core portion 22 facing one magnetic pole 51 in the radial direction in the direction from the permanent magnet 50 toward the stator 3. The point where the radial distance from one pole 51 is maximum, and the point where the radial distance from the permanent magnet 50 in the armature side field magnetic core portion 22 facing the other magnetic pole 52 adjacent to one magnetic pole 51 is maximum. The opening width, which is the length of the straight line connecting the two, is Wh1, and is the width in the moving direction, that is, the circumferential direction, which is the direction perpendicular to the magnetizing direction corresponding to one pole of the magnetic pole 51 or the magnetic pole 52 of the permanent magnet 50. The magnetic pole width is Wmag. At this time, it is desirable that the opening width Wh1 is set to be smaller than the magnetic pole width Wmag and larger than the minimum length g of the gap 1. That is, it is desirable that g <Wh1 <Wmag.

This is because, in FIG. 3, the size of the hole 11 is not sufficient to suppress the flow of the magnetic flux 20 through the path B of the magnetic flux 20 short-circuiting between the magnetic pole 51 and the magnetic pole 52, that is, the magnetic flux boundary. If the magnetic resistance of the path B of the magnetic flux 20 straddling the extension of 10 is low, the magnetic flux 20 from the magnetic pole 51 may pass through the path B of the magnetic flux 20 and be short-circuited to the adjacent magnetic pole 52, resulting in a decrease in torque. Because there is. When g <Wh1, the magnetic flux 20 flowing through the magnetic pole 51 and the magnetic pole 52 is more likely to pass through the gap 1 than the opening width Wh1. Further, when Wh1 <Wmag, the range in which the opening width Wh1 overlaps in the circumferential direction of the magnetic poles 51 and 52 is smaller than the magnetic pole width Wmag, and the magnetic flux 20 of the magnetic poles 51 and 52 passes in the circumferential direction range of the hole portion 11. It is possible to prevent the length of the void 1 from expanding beyond the minimum length g. Due to this dimensional relationship, the magnetic flux density in the gap 1 between the rotor 2 and the stator 3 can be efficiently increased, and the torque can be further increased.

Further, in FIG. 3, in the armature side field core portion 22, the radial width in the direction from the permanent magnet 50 toward the stator 3 at the position of the adjacent surface 24 is set to th1, and in the armature side field core portion 22. Let tb be the minimum width in the direction from the circumferential end of the permanent magnet 50 toward the stator 3. Further, the portion of the armature side field core portion 22 including the portion having the width th1 and the portion of the rotor core 15 in the same range as the circumferential range of the hole portion 11 is referred to as the first bridge portion, that is, the thin-walled portion 13, and th1 is defined as the first bridge portion. The width of the thin portion 13 is set. Further, the stator 3 side from the flux barrier 7 from the portion having the minimum width tb at the boundary of the armature side field core portion 22 to the minimum width tb of the boundary of the armature side field core portions 22 adjacent to each other in the circumferential direction. The portion of the rotor core 15 located at is referred to as the second bridge portion 26. The second bridge portion 26 straddles the position of the central surface 25, which is a surface located in the center of the circumferential direction between the permanent magnets 50 adjacent to each other in the circumferential direction.

In order to cause magnetic saturation in the thin-walled portion 13, it is desirable to set the width th1 of the thin-walled portion 13 as small as possible. That is, it is desirable that the width th1 of the thin portion 13 is tb ≦ th1 <Wh1 / 2 with respect to the minimum width tb and the opening width Wh1. This is because the lower limit of the width th1 of the thin wall portion 13 is set to the minimum width tb having the strength to hold the centrifugal force generated in the permanent magnet 50 due to the rotation of the rotor, or the minimum width tb having a dimension capable of punching an electromagnetic steel sheet. Because it is necessary. Further, when th1 <Wh1 / 2, the amount of the magnetic flux passing through the width th1 of the thin wall portion 13 among the magnetic flux 20 flowing through the magnetic pole 51 and the magnetic pole 52 is larger than the amount of the magnetic flux flowing from the opening width Wh1 to the void 1. This is because it also becomes smaller. Due to this dimensional relationship, the magnetic flux 20 generated by the permanent magnet 50 or the magnetic flux generated by the stator 3 tends to cause magnetic saturation in the thin portion 13. When magnetic saturation occurs in the thin-walled portion 13, the relative magnetic permeability of the thin-walled portion 13 becomes close to that of air. Therefore, the torque generated by the rotary electric machine 200 can be further increased.

It should be noted that g <Wh1 <Wmag and tb ≦ th1 <Wh1 / 2 are dimensions that can be set individually, and the effect of increasing torque is also exhibited in each. Further, if g <Wh1 <Wmag and tb ≦ th1 <Wh1 / 2, the torque is increased as compared with the case where any of the dimensional relationships is set.

Further, when the electromagnetic steel sheet generally used for the rotor core 15 is manufactured by punching, the magnetic resistance is affected by the processing deterioration due to the punching within the range from the contour of the punched shape to the thickness of the electromagnetic steel sheet. It increases and magnetic saturation is likely to occur in this range. Therefore, it is desirable that the width th1 of the thin-walled portion 13 is two or less, preferably one or less, of the electrical steel sheet.

Next, the effect of torque ripple in the rotary electric machine 200 of the present embodiment will be described.
FIG. 4 is a diagram showing a waveform of the magnetic flux density of the void of the electric machine in the present embodiment. In FIG. 4, the horizontal axis represents the position in the circumferential direction of the rotor of the rotary electric machine 200, that is, the rotation angle of the rotor is represented by an electric angle [deg], and the vertical axis represents the magnetic flux density in the void 1 in the void 1 of FIG. It is expressed as a standardized value by the maximum value of the magnetic flux density in. In FIG. 4, the waveform of the magnetic flux density in the void 1 of the rotary electric machine 200, which is an electric machine in the present embodiment, has a sinusoidal shape. Further, in FIG. 4, the position where the magnetic flux density becomes 0 is the position in the circumferential direction between the magnetic poles having different poles, that is, the position in the electric angle 180 [deg] which is the circumferential position of the adjacent surface 24, and the field iron core 15. It is the position in the circumferential direction between the flux barriers 7 adjacent to each other, that is, the position of the electric angle 0 [deg] or 360 [deg], which is the position of the central surface 25.

FIG. 5 is a partial cross-sectional view of a first comparative example of an electric machine according to the present embodiment.
In FIG. 5, the rotary electric machine 300, which is the first comparative example of the electric machine in the present embodiment, has the same stator 303 as the stator 3 shown in FIG. 2 and a permanent magnet 350 embedded in the rotor core 315. It has a magnet type rotor 302. The rotor 302 of the rotary electric machine 300 of FIG. 5 differs from the rotary electric machine 200 of FIG. 3 in that a recess 312 is formed instead of the hole 11. Other configurations of the rotary electric machine 300 are the same as those of the rotary electric machine 200 of FIG.

In FIG. 5, similar to the rotary electric machine 200 of the present embodiment of FIG. 3, one permanent magnet 350 in the rotary electric machine 300 has magnetic poles 351 and 352 having different poles on the stator 303 side in the moving direction. It is formed by being magnetized adjacent to a certain circumferential direction. In the armature side field core portion 322, which is the rotor core 315 located on the stator 300 side of the permanent magnet 350 in the rotor 302, the recess 312 recessed from the magnet insertion hole 319 toward the stator 300 side is formed. The magnetic poles 351 and 352 are formed at the position of the adjacent surface 324 including the magnetic pole boundary 310 which is an adjacent surface. That is, in the rotary electric machine 300, the outer peripheral portion of the rotor core 315 on the stator 300 side of the permanent magnet 350 is connected by the thin-walled portion 313.

FIG. 6 is a diagram showing a waveform of the magnetic flux density of the void in the first comparative example of the electric machine in the present embodiment. In FIG. 6, the horizontal axis represents the position of the rotary electric machine 300 in the circumferential direction, that is, the rotation angle of the rotor is represented by an electric angle [deg], and the vertical axis represents the gap 301 of the rotary electric machine 300 of the first comparative example. The magnetic flux density in FIG. 5 is represented by a value standardized by the maximum value of the magnetic flux density in the void 301 in FIG. In FIG. 6, the waveform of the magnetic flux density in the gap 301 of the rotary electric machine 300 of the first comparative example of the electric machine in the present embodiment is in the gap 1 rather than the waveform of the magnetic flux density in the gap 1 of the rotary electric machine 200 in FIG. It is a trapezoidal waveform that contains many harmonic components in the space in the circumferential direction. Here, the harmonic component in the space in the circumferential direction is a harmonic component when the waveform of two poles of the magnetic pole 51 and the magnetic pole 52, that is, the waveform for one cycle of the electric angle is frequency-analyzed.

In the rotary electric machine 300 of FIG. 5, the outer peripheral portion of the armature side field magnetic core portion 322, which is the rotor core 315 on the stator 300 side of the permanent magnet 350, is connected by the thin wall portion 313. Therefore, in the rotary electric machine 300 of FIG. 5, the magnetic flux 320 of the permanent magnet 350 flows through the thin-walled portion 313 connected at the outer peripheral portion of the armature side field iron core portion 322.

On the other hand, in the rotary electric machine 200 of the present embodiment of FIG. 3, a hole 11 recessed from the virtual surface 90 toward the permanent magnet 50 is formed at the position of the adjacent surface 24. Therefore, the magnetic flux 20 of the permanent magnet 50 is the thin portion 13 of the armature side field iron core portion 22 connected at a portion closer to the permanent magnet 50 side than the outer peripheral portion of the armature side field iron core portion 22. Flow.
Therefore, the magnetic flux density of the gap 1 in the adjacent surface 24 located between the magnetic poles 51 and 52 in the rotary electric machine 200 is the gap 301 in the magnetic pole boundary 310 located between the magnetic poles 351 and 352 in the rotary electric machine 300 of the first comparative example. It is lower than the magnetic flux density of. Therefore, as shown in FIG. 6, the harmonic component of the magnetic flux density in the gap 1 of the rotary electric machine 200 is smaller than the harmonic component of the magnetic flux density in the gap 301 of the rotary electric machine 300.

As a result, the torque ripple of the rotary electric machine 200 of the present embodiment of FIG. 3 is reduced as compared with the torque ripple of the rotary electric machine 300 of the first comparative example. That is, when two magnetic poles 51 and 52 having different poles on the stator 3 side of one permanent magnet 50 embedded in the rotor core 15 are adjacent to each other in the moving direction, the rotary electric machine of the present embodiment is used. In 200, torque ripple can be reduced as compared with the case where the outer peripheral portion of the armature side field iron core portion 322 on the stator 300 side of the permanent magnet 350 is connected.

FIG. 7 is a diagram showing a 6f component of torque ripple in the electric machine according to the present embodiment and the electric machine of the first comparative example. In FIG. 7, the horizontal axis represents the rotary electric machine 300 of the first comparative example of FIG. 5 and the rotary electric machine 200 of FIG. 3, and the vertical axis represents the case where the 6f component of the torque ripple of the first comparative example is 100. Represents the 6f component of torque ripple. Here, the 6f component of the torque ripple is the amplitude value of the torque ripple of 6 peaks per cycle of the electric angle when a predetermined current is applied to the stator, and is the main component of the torque ripple. As a result of the electromagnetic field analysis, the 6f component of the torque ripple of the rotary electric machine 200 of FIG. 3 is 12% lower than the 6f component of the torque ripple of the rotary electric machine 300 of the first comparative example. This is because the hole 11 of the rotary electric machine 200 in FIG. 3 can reduce the harmonic component of the magnetic flux density in the gap 1 of the rotary electric machine 200 more than the harmonic component of the magnetic flux density in the gap 301 of the rotary electric machine 300. .. Therefore, the torque ripple of the rotary electric machine 200 of the present embodiment of FIG. 3 can be reduced as compared with the torque ripple of the rotary electric machine 300 of the first comparative example.

The cross-sectional shape of the hole portion 11 is not limited to a shape symmetrical in the circumferential direction with respect to the adjacent surface 24, and if the shape is recessed from the virtual surface 90 toward the permanent magnet 50, the shape is peripheral to the adjacent surface 24. The shape may be asymmetrical in the direction. Even if the cross-sectional shape of the hole 11 is asymmetric in the circumferential direction with respect to the adjacent surface 24, the harmonic component of the magnetic flux density in the void 1 of the rotary electric machine 200 and the harmonic component of the magnetic flux density in the void 301 of the rotary electric machine 300 can be obtained. The torque ripple of the rotary electric machine 200 can be reduced more than the torque ripple of the rotary electric machine 300 of the first comparative example.

Next, the effect of the torque of the rotary electric machine 200 of the present embodiment will be described.
In the rotary electric machine 200 of the present embodiment, the armature side field magnetic core is different from the rotary electric machine of the second comparative example in the case where the hole 11 of the rotary electric machine 200 of the present embodiment is not provided in the rotor core. The hole portion 11 provided in the portion 22 increases the magnetic resistance of the armature-side field iron core portion 22.

Specifically, in FIG. 3, in the hole portion 11, the magnetic flux 20 follows the path B of the magnetic flux 20 that short-circuits between the magnetic pole 51 and the magnetic pole 52 at the position of the adjacent surface 24 of the armature side field iron core portion 22. It is provided to prevent the flow. Due to this hole portion 11, the cross-sectional area of the adjacent surface 24 of the thin-walled portion 13 of the armature side field iron core portion 22 is smaller than that of the rotary electric machine of the second comparative example. Therefore, the magnetic resistance in the path B of the magnetic flux 20 that short-circuits between the magnetic pole 51 and the magnetic pole 52 in the rotary electric machine 200 in the present embodiment is the second comparative example in which the hole 11 is not provided in the rotor core. It will increase more than in the case of a rotary electric machine.

Therefore, the magnetic flux 20 that short-circuits the adjacent magnetic poles 51 and 52 is suppressed as compared with the case of the rotary electric machine of the second comparative example. As a result, the torque generated by the rotary electric machine 200 of FIG. 3 can be increased more than the torque generated by the rotary electric machine of the second comparative example.

Next, the effect of manufacturability on the permanent magnet 50 in the rotary electric machine 200 of the present embodiment will be described.
Assuming that the total number of magnetic poles of the rotary electric machine of the third comparative example is eight, which is the same as the total number of the magnetic poles 51 and 52 of FIG. The number of holes and the number of permanent magnets are eight, which is the same as the total number of magnetic poles. In this case, the number of magnet insertion holes or permanent magnets of the rotary electric machine of the third comparative example is eight, which is twice as many as four in the present embodiment. In the rotary electric machine of the third comparative example, one magnetic pole having an N pole or one magnetic pole having an S pole is formed on the stator-side surface of one permanent magnet embedded in the rotor. Has been done.
Therefore, in the rotary electric machine of the third comparative example, the number of steps for shaping the permanent magnet, the number of steps for magnetizing the permanent magnet, and the number of steps for inserting the permanent magnet into the magnet insertion hole depend on the total number of magnetic poles. There was a problem that it increased and the manufacturing cost increased.

On the other hand, in the rotary electric machine 200 of the present embodiment, one flat plate-shaped permanent magnet 50 is formed by magnetizing two magnetic poles 51 and 52. Further, the number of magnet insertion holes 19 or permanent magnets 50 is four, which is half that of the rotary electric machine of the third comparative example. Therefore, the man-hours for shaping the permanent magnet 50 of the rotary electric machine 200 of the present embodiment is halved as compared with the rotary electric machine of the third comparative example.
Further, when the permanent magnet 50 is magnetized before the permanent magnet 50 is inserted into the magnet insertion hole 19, the permanent magnet 50 is magnetized once, so that the rotation of the present embodiment is performed. The number of magnetizing steps in the electric machine 200 is half that of the rotary electric machine of the third comparative example.
Further, the man-hours for inserting the permanent magnet 50 of the rotary electric machine 200 of the present embodiment into the magnet insertion hole 19 is also halved as compared with the rotary electric machine of the third comparative example.

Therefore, in the rotary electric machine 200, the man-hours for shaping the permanent magnet 50, the man-hours for magnetizing the permanent magnet 50 for generating the magnetic poles 51 and 52, and the man-hours for inserting the permanent magnet 50 into the magnet insertion hole 19 can be reduced. .. Therefore, the manufacturing cost of the rotary electric machine 200 of the present embodiment can be reduced as compared with the rotary electric machine of the third comparative example.

Next, the first modification 200a of the rotary electric machine of this embodiment will be described.
FIG. 8 is a partial cross-sectional view of the first modification 200a of the electric machine according to the present embodiment. In FIG. 8, in addition to the hole portion 11 formed at the position of the adjacent surface 24 in the rotary electric machine 200 shown in FIG. 3, the notch portion 23 is also formed between the adjacent permanent magnets 50 on the outer peripheral portion of the rotor core 15a. Is provided. That is, the notch 23 recessed from the virtual surface 90 in the direction from the stator 3 toward the rotor core 15a is located at the center of the circumferential direction between the permanent magnets 50 adjacent to each other in the circumferential direction in the rotor core 15a. It is formed at the position of the central surface 25, which is the surface to be used.

Further, when the permanent magnets 50-1 and 50-2 adjacent to each other in the circumferential direction across the notch 23 are used as the first permanent magnet 50-1 and the second permanent magnet 50-2, the first permanent magnet is used. The armature side field magnetic core at the position of the adjacent surface 24-1, which is the surface including the magnetic pole boundary 10-1, which is one end surface in the circumferential direction of the first magnetic pole 51-1 closest to the notch 23 in 50-1. A first hole portion 11-1 is formed in the portion 22. In the rotor core 15a, a first magnetic pole 51-1 is formed between the first hole portion 11-1 and the notch portion 23, and the permanent magnet 50-1 projects toward the stator 3. The protruding portion 30a-1 of 1 is formed. The armature side field at the position of the adjacent surface 24-2 including the magnetic pole boundary 10-2, which is one end surface in the circumferential direction of the second magnetic pole 52-2 closest to the notch 23 in the second permanent magnet 50-2. A second hole portion 11-2 is formed in the magnetic iron core portion 22-2. Then, in the rotor core 15a, the second protruding portion 30a-protruding from the second permanent magnet 50-2 toward the stator 3 between the second hole portion 11-2 and the notch portion 23. 2 is formed.

By combining the notch 23 and the flux barrier 7 between the first protrusion 30a-1 and the second protrusion 30a-2, the short circuit of the magnetic flux 20 between the adjacent permanent magnets 50 is suppressed. can do. Therefore, the torque of the rotary electric machine 200a of FIG. 8 is larger than the torque of the rotary electric machine 200 of FIG. Even when the flux barrier 7 is not provided, the short circuit of the magnetic flux 20 between the adjacent permanent magnets 50 can be suppressed only by the notch portion 23 as compared with the case where the notch portion 23 is not provided.

Further, the gap 1 between the magnetic flux 51-1 and the magnetic pole 52-2, which is between the adjacent permanent magnets 50-1 and 50-2, is caused by the first protrusion 30a-1 and the second protrusion 30a-2. The magnetic flux density of the can be reduced. Therefore, it is possible to secure the symmetry of the magnetic flux density of the gap 1 with respect to the central surface 25 between the magnetic poles 51-1 and the magnetic poles 52-2 of the rotor core 15a. That is, the waveform of the magnetic flux density of the gap 1 approaches antisymmetry with respect to the central surface 25 between the magnetic poles 51-1 and the magnetic poles 52-2. Therefore, the first modification 200a of the rotary electric machine can reduce the torque ripple as compared with the rotary electric machine 200 of FIG.

In the present embodiment, the number of magnetic poles 51 and 52 appearing in the gap 1 by the permanent magnet 50 is eight, that is, eight poles, and the number of slots 21 is twelve rotary electric machines 200 and 200a. However, the magnetic poles 51 and 52 The combination of the number of slots and the number of slots 21 may be any combination that satisfies the desired characteristics of the rotary electric machine.

In the present embodiment, the rotors 2 and 2a are housed in the inner diameter side of the stator 3 and face the inner diameter side of the stator 3, which is the structure of the inner rotor type rotary electric machines 200 and 200a. The same effect can be obtained with the structure of an outer rotor type rotary electric machine in which the rotors 2 and 2a are arranged so as to face each other on the outer diameter side of 3.

In the case of the inner rotor type, the cross-sectional area of the stator core 16 perpendicular to the axial direction of the slot 21 can be made larger than the cross-sectional area of the outer rotor type slot. Therefore, the copper loss of the stator 3 can be reduced.
Further, in the case of the outer rotor type, since the centrifugal force does not act on the thin-walled portion of the rotor core, the thickness of the thin-walled portion of the rotor core should be smaller than the thickness of the thin-walled portion 13 of the inner rotor type rotor core 15. Can be done.

Embodiment 2.
FIG. 9 is a cross-sectional view taken along the line AA of FIG. 1 in the rotor of the second modification of the electric machine in the second embodiment for carrying out the present invention. FIG. 10 is a partial cross-sectional view of a second modification of the electric machine according to the present embodiment. In FIGS. 9 and 10, the second modification 200b of the rotary electric machine, which is an electric machine, is different from the first modification 200a of the rotary electric machine according to the first embodiment in the following points.

In FIG. 9, in the first protrusion 30b-1, the shape of the cross section perpendicular to the axial direction is arcuate, and in the second protrusion 30b-2, the shape of the cross section perpendicular to the axial direction is a circle. It has an arc shape. The radius of curvature of the first protrusion 30b-1 is r1, the radius of curvature of the second protrusion 30b-2 is r2, and the radius of curvature of the cross section perpendicular to the axial direction in the virtual surface 90 shown in FIG. 10 is R. do. At this time, the radius of curvature r1 of the first protrusion 30b-1 and the radius of curvature r2 of the second protrusion 30b-2 are smaller than the radius of curvature R of the virtual surface 90, respectively. That is, r1 <R and r2 <R. In FIGS. 9 and 10, the radius of curvature r1 of the first protrusion 30b-1 and the radius of curvature r2 of the second protrusion 30b-2 are equal to each other. That is, r1 = r2. Further, in the cross section perpendicular to the axial direction, the first protruding portion 30b-1 and the second protruding portion 30b-2 are inscribed in the virtual surface 90, respectively. In addition, r1 ≠ r2 may be set.

By providing the first protruding portion 30b-1 and the second protruding portion 30b-2 having an arcuate cross-sectional shape perpendicular to the axial direction, the magnetic flux in the gap 1 between the rotor 2b and the stator 3 is provided. The density waveform can be made closer to a sine wave. Therefore, the torque ripple generated by the second modification 200b of the rotary electric machine can be reduced as compared with the first modification 200a of the rotary electric machine.

In FIG. 10, in the circumferential range occupied by the hole portion 11a, the radial distance from the permanent magnet 50 in the armature side field iron core portion 22a-1 facing one magnetic pole 51-1 is maximized. , The length of the straight line connecting the point where the radial distance from the permanent magnet 50 in the armature side field iron core portion 22a-1 facing the other magnetic pole 52-1 adjacent to one magnetic pole 51-1 is maximum. Let the opening width be Wh2. The definition of Wmag is the same as in FIG.

At this time, it is desirable that the opening width Wh2 is set to be smaller than the magnetic pole width Wmag and larger than the minimum length g of the gap 1. That is, it is desirable to set the radius of curvature r1 of the first protrusion 30b-1 and the radius of curvature r2 of the second protrusion 30b-2 so that g <Wh2 <Wmag. This is because, in FIG. 10, the hole portion 11a has a size that is not sufficient to prevent the magnetic flux 20 from flowing through the path C of the magnetic flux 20 that short-circuits between the magnetic pole 51-1 and the magnetic pole 52-1, that is, the magnetic pole. When the magnetic resistance of the path C of the magnetic flux 20 straddling the extension of the boundary 10-1 is low, the magnetic flux 20 from the magnetic flux 51-1 passes through the path C of the magnetic flux 20 and is short-circuited to the adjacent magnetic pole 52-1. This is because the torque generated by the second modification 200b of the rotary electric machine may be reduced. When g <Wh2, the magnetic flux 20 flowing through the magnetic poles 51-1 and the magnetic poles 52-1 is easier to pass through the gap 1 than the opening width Wh2. Further, when Wh2 <Wmag, the range in which the opening width Wh2 and the magnetic poles 51-1 and 52-1 overlap in the circumferential direction is smaller than the magnetic pole width Wmag. Therefore, it is possible to prevent the length of the gap 1 through which the magnetic flux 20 of the magnetic poles 51-1 and 52-1 passes in the circumferential range of the hole portion 11a from expanding beyond the minimum length g. Therefore, it is possible to prevent the magnetic resistance in the void 1 from increasing and the magnetic flux 20 from becoming difficult to flow into the stator 3. Due to this dimensional relationship, the magnetic flux density in the gap 1 between the rotor 2b and the stator 3 can be efficiently increased, and the torque generated by the second modification 200b of the rotary electric machine can be further increased. It becomes.

Further, in FIG. 10, the radial width in the direction from the permanent magnet 50-1 to the stator 3 at the position of the adjacent surface 24 in the armature side field iron core portion 22a-1 is defined as th2, and the armature side field magnet is used. Let tb be the minimum width in the direction from the circumferential end of the permanent magnet 50-1 toward the stator 3 in the iron core portion 22a-1. Further, the portion of the armature side field core portion 22a-1 including the portion having the width th2 and the portion of the rotor core 15b in the same range as the circumferential range of the hole portion 11a is designated as the first bridge portion, that is, the thin-walled portion 13a. Let th2 be the width of the thin portion 13a. Further, from the flux barrier 7 from the portion having the minimum width tb at the boundary of the armature side field core portion 22a-1 to the minimum width tb at the boundary of the armature side field core portions 22a-2 adjacent in the circumferential direction. The portion of the rotor core 15b located on the stator 3 side is referred to as the second bridge portion 26a.

In order to cause magnetic saturation in the thin-walled portion 13a, it is desirable to set the width th2 of the thin-walled portion 13a as small as possible. That is, it is desirable that the width th2 of the thin portion 13a is tb ≦ th2 <Wh2 / 2 with respect to the minimum width tb and the opening width Wh2. This is because the lower limit of the width th2 of the thin portion 13a is the minimum width tb having the strength necessary for maintaining the centrifugal force generated in the permanent magnet 50-1 by the rotation of the rotor 2b, or the dimension capable of punching an electromagnetic steel sheet. This is because the minimum width tb needs to be set. Further, when th2 <Wh2 / 2, the amount of the magnetic flux passing through the width th2 of the thin portion 13a among the magnetic flux 20 flowing through the magnetic poles 51-1 and the magnetic poles 52-1 flows from the opening width Wh2 to the void 1. This is because it is smaller than the amount of magnetic flux. Due to this dimensional relationship, the magnetic flux 20 generated by the permanent magnet 50-1 or the magnetic flux generated by the stator 3 tends to cause magnetic saturation in the thin portion 13a. When the thin-walled portion 13a is magnetically saturated, the relative magnetic permeability of the thin-walled portion 13a is close to that of air. Therefore, the torque generated by the second modification 200b of the rotary electric machine can be further increased.

It should be noted that g <Wh2 <Wmag and tb ≦ th2 <Wh2 / 2 are dimensions that can be set individually, and the effect of increasing torque is also exhibited in each. Further, if g <Wh2 <Wmag and tb ≦ th2 <Wh2 / 2, the torque generated by the second modification 200b of the rotary electric machine increases as compared with the case where it is set in any dimensional relationship.

In FIG. 9, the notch 23a formed at the position of the central surface 25, which is the surface located at the center of the circumferential direction between the permanent magnets 50-1 and 50-2 adjacent to each other in the circumferential direction, is formed. The virtual surface 90 may be filled with the rotor core 15b. When the hole portion 11a recessed from the virtual surface 90 toward the permanent magnets 50-1 and 50-2 is formed in the armature side field iron core portion 22a-1, the armature side field in which the hole portion 11a is formed is formed. The shape of the cross section perpendicular to the axial direction of the magnetic iron core portion 22a-1 is a shape in which two arcs are connected in the circumferential direction. Therefore, the harmonic component of the magnetic flux density waveform of the void 1 in the circumferential range of the hole portion 11a between the rotor 2b and the stator 3 can be reduced, and the magnetic flux density waveform of the void 1 can be made closer to a sine wave. .. Therefore, the second modification 200b of the rotary electric machine can reduce the torque ripple as compared with the rotary electric machine 200 of FIG.

Embodiment 3.
As an example in which the shape of the hole portion 11 in FIG. 3 is different, four modified examples of the rotary electric machine according to the third embodiment for carrying out the present invention will be described.

FIG. 11 is a partial cross-sectional view of a third modification of the electric machine according to the third embodiment for carrying out the present invention. In FIG. 11, the third modification 200c of the rotary electric machine, which is an electric machine, is different from the rotary electric machine 200 according to the first embodiment in the points described below.
In FIG. 11, the shape of the cross section perpendicular to the axial direction of the hole portion 11 in FIG. 3 is a trapezoidal shape, whereas the shape of the cross section is perpendicular to the axial direction of the hole portion 11b in the third modification 200c of the rotary electric machine which is an electric machine. The shape of the cross section is a trapezoidal shape in which one apex portion of the triangular shape is cut by the virtual surface 90. The apex of the triangle, which is the shape of the cross section of the hole portion 11b, is in the gap 1 at the position of the adjacent surface 24 of the rotor core 15c. Therefore, the outer periphery of the rotor core 15c on the adjacent surface 24 is opened toward the stator 3 by the opening width Wh3 in the circumferential direction. Here, in the circumferential range occupied by the hole portion 11b, the point where the radial distance from the permanent magnet 50 in the armature-side field iron core portion 22b facing the one magnetic pole 51 is maximum, and the one magnetic pole 51. The opening width, which is the length of a straight line connecting the point where the radial distance from the permanent magnet 50 in the armature side field iron core portion 22b facing the other magnetic pole 52 adjacent to the permanent magnet 50 is maximum, is defined as Wh3. Further, in the armature-side field iron core portion 22b, a thin-walled portion 13b, which is a first bridge portion arranged so as to straddle the positions of the adjacent surfaces 24 in the circumferential direction, is formed. The thin-walled portion 13b, which is the first bridge portion, includes a portion having a width th3 in the armature side field core portion 22b, and is a portion of the rotor core 15c in the same range as the circumferential range of the hole portion 11b, and is in the circumferential direction. The width of is Whm3. The width th3 in the direction from the permanent magnet 50 to the stator 3 in the thin portion 13b is constant in the circumferential direction within the range of Whm3. In FIG. 11, Wh3 <Whm3.

When the opening width Wh1 and the opening width Wh3 of the hole portion 11 in FIG. 3 have the same length, and the width th1 of the thin-walled portion 13 and the width th3 of the thin-walled portion 13b have the same length, the width th3 of the thin-walled portion 13b. Is constant in the circumferential direction within the range of the circumferential width Whm3 of the thin wall portion 13b, so that the length of the path D of the magnetic flux 20 is larger than the length of the path B of the magnetic flux 20 in FIG. Therefore, the magnetic resistance of the path D of the magnetic flux 20 is higher than the magnetic resistance of the path B of the magnetic flux 20 in FIG. Therefore, the magnetic flux density increases on the outer peripheral side of the rotor core 15c and magnetic saturation is likely to occur, so that the short circuit of the magnetic flux 20 in the thin-walled portion 13b is suppressed. Therefore, the torque of the third modification 200c of the rotary electric machine of FIG. 11 is higher than that of the rotary electric machine 200 of FIG.

FIG. 12 is a partial cross-sectional view of a fourth modification of the electric machine according to the present embodiment. In FIG. 12, the fourth modification 200d of the rotary electric machine, which is an electric machine, is different from the third modification 200c of the rotary electric machine according to the present embodiment in that it is described below.
In FIG. 12, the opening width Wh4 of the hole portion 11c and the circumferential width Whm4 of the thin-walled portion 13c are equal to each other. That is, the shape of the cross section perpendicular to the axial direction of the hole portion 11c in the fourth modification 200d of the rotary electric machine is a rectangular shape, that is, a rectangular shape. Further, when the circumferential width Whm4 of the thin wall portion 13c and the circumferential width Whm3 of the thin wall portion 13b of the hole portion 11b in FIG. 11 are equal to each other, the opening width Wh4 is the opening width of the third modification 200c of the rotary electric machine. It will be larger than Wh3.

Since the opening width Wh4 is larger than the opening width Wh3 of the third modification 200c of the rotary electric machine, the magnetic resistance that the magnetic flux 20 passes through the opening width Wh4 causes the magnetic flux 20 to pass through the opening width Wh3 of the third modification 200c of the rotary electric machine. Increases more than the reluctance that passes through. Therefore, in the fourth modification 200d of the rotary electric machine, the magnetic flux 20 flowing from the armature side field core portion 22c of the rotor core 15d to the stator 3 leaks to the opening width Wh4, which is the third modification of the rotary electric machine. It can be suppressed more than the case of 200c. Therefore, the torque generated by the fourth modified example 200d of the rotary electric machine is larger than that of the third modified example 200c of the rotary electric machine of FIG.

Further, when the width Whm4 in the circumferential direction of the thin-walled portion 13c and the width Whm3 in the circumferential direction of the thin-walled portion 13b of the hole portion 11b in FIG. 11 are equal, the shape of the cross section of the hole portion 11b in FIG. 10 is triangular. For the same reason, the torque generated by the fourth modification 200d of the rotary electric machine is higher than that of the rotary electric machine 200 of FIG.

Further, in the case of the hole portion 11c of FIG. 12, the magnetic flux density waveform generated in the void 1 is closer to the sinusoidal shape than in the case of the hole portion 11b of FIG. This is because in the fourth modification 200d of the rotary electric machine, the magnetic flux 20 flowing from the armature side field iron core portion 22c to the stator 3 leaks to the opening width Wh4, as compared with the case of the third modification 200c of the rotary electric machine. This is because it can be suppressed. Therefore, the harmonic component of the magnetic flux density waveform of the gap 1 in the circumferential range of the hole portion 11c is smaller than that of the hole portion 11b in FIG. Therefore, the torque ripple generated by the fourth modified example 200d of the rotary electric machine is reduced as compared with the case of the third modified example 200c of the rotary electric machine.

FIG. 13 is a partial cross-sectional view of a fifth modification of the electric machine according to the present embodiment. In FIG. 13, the fifth modification 200e of the rotary electric machine, which is an electric machine, is different from the fourth modification 200d of the rotary electric machine according to the present embodiment in that it is described below.
In FIG. 13, in the armature side field core portion 22d of the rotor core 15e, a recess 12 recessed from the magnet insertion hole 19 toward the stator 3 side is formed at the position of the adjacent surface 24. The circumferential width Whm5 of the thin wall portion 13d, which is the first bridge portion between the concave portion 12 and the hole portion 11d, is equal to the opening width Wh5 and the circumferential opening width Wo1 of the concave portion 12. Further, the thin portion 13d is separated from the permanent magnet 50 with a predetermined length Do1 in the radial direction. The shape of the cross section perpendicular to the axial direction of the recess 12 in the fifth modification 200e of the rotary electric machine is a rectangular shape, that is, a rectangular shape.

A recess 12 is formed and the thin-walled portion 13d is separated from the permanent magnet 50 with a length Do1 in the radial direction, so that the length of the path E of the magnetic flux 20 passing through the thin-walled portion 13d is a fourth modification of the rotary electric machine. It is larger than the length of the path D of the magnetic flux 20 of 200d. Therefore, the magnetic resistance in the thin-walled portion 13d is higher than the magnetic resistance in the thin-walled portion 13d of the fourth modification 200d of the rotary electric machine. Therefore, in the fifth modification 200e of the rotary electric machine, the magnetic flux 20 flowing from the armature side field iron core portion 22d to the stator 3 leaks to the thin wall portion 13d as compared with the case of the fourth modification 200d of the rotary electric machine. Can be suppressed. Therefore, the torque generated by the fifth modification 200e of the rotary electric machine is higher than that of the fourth modification 200d of the rotary electric machine.

FIG. 14 is a partial cross-sectional view of a sixth modification of the electric machine according to the present embodiment. In FIG. 14, the sixth modification 200f of the rotary electric machine, which is an electric machine, is different from the fourth modification 200d of the rotary electric machine according to the present embodiment in that it is described below.
In FIG. 14, the hole portion 11e penetrates from the gap 1 to the magnet insertion hole 19. Assuming that the opening width of the hole portion 11e is Wh6, the hole portion 11e penetrates from the gap 1 to the magnet insertion hole 19 with the width of the opening width Wh6. Further, the hole portion 11e has a shape obtained by removing the thin wall portion 13c from the hole portion 11c of the fourth modification 200d of the rotary electric machine.

When the opening width Wh6 of the hole portion 11e in FIG. 14 is equal to the opening width Wh4 of the hole portion 11c of the fourth modification 200d of the rotary electric machine, the magnetic resistance through which the magnetic flux 20 passes through the opening width Wh6 is the fourth deformation of the rotary electric machine. It increases more than the magnetic resistance in the thin portion 13c of Example 200d. Therefore, in the sixth modification 200f of the rotary electric machine, the magnetic flux 20 flowing from the armature side field core portion 22e of the rotor core 15f to the stator 3 leaks to the opening width Wh6, which is the fourth modification of the rotary electric machine. It can be suppressed more than the case where it leaks to the thin wall portion 13c at 200d. Therefore, the torque generated by the sixth modification 200f of the rotary electric machine is higher than that of the fourth modification 200d of the rotary electric machine.

Further, in the case of the hole portion 11e, the magnetic flux density waveform generated in the gap 1 becomes a waveform closer to the sinusoidal shape than in the case of the hole portion 11c in FIG. This is because in the sixth modification 200f of the rotary electric machine, the magnetic flux 20 flowing from the armature side field iron core portion 22e to the stator 3 leaks to the opening width Wh6 as compared with the case of the fourth modification 200d of the rotary electric machine. This is because it can be suppressed. Therefore, the harmonic component of the magnetic flux density waveform of the gap 1 in the circumferential range of the hole portion 11e is smaller than that of the hole portion 11c in FIG. Therefore, the torque ripple generated by the sixth modification 200f of the rotary electric machine is reduced as compared with the case of the fourth modification 200d of the rotary electric machine.

Embodiment 4.
FIG. 15 is a partial cross-sectional view of a seventh modification of the electric machine in the fourth embodiment for carrying out the present invention. In FIG. 15, the seventh modification 200 g of the rotary electric machine is different from the rotary electric machine 200 according to the first embodiment in the points described below.

In FIG. 15, in the permanent magnet 50a-1, magnetic poles 51a and 52a having different poles on the stator 3 side are adjacent to each other in the circumferential direction, and four different poles are formed side by side in the circumferential direction. That is, in FIG. 15, the magnetic pole 51a is magnetized so as to have an N pole on the surface on the stator 3 side, and the magnetic pole 52a has an S pole on the surface on the stator 3 side. Therefore, in FIG. 15, on the surface of the permanent magnet 50a-1 on the stator 3 side, the north pole of the magnetic pole 51a is directed from the left end portion on one end side in the circumferential direction toward the right end portion on the other end side in the circumferential direction. It is formed side by side with a pole, an S pole of the magnetic pole 52a, an N pole of the magnetic pole 51a, and an S pole of the magnetic pole 52a. Further, also in the permanent magnet 50a-2 adjacent to the permanent magnet 50a-1 in the circumferential direction, the north pole of the magnetic pole 51a and the S pole of the magnetic pole 52a are directed from one end side in the circumferential direction to the other end side in the circumferential direction. , The pole of the north pole of the magnetic pole 51a and the pole of the south pole of the magnetic pole 52a are formed side by side. Further, on the surface where the magnetic poles 51a and 52a are adjacent to each other in the circumferential direction, the magnetic pole boundaries 10a-1 and 10a-2 are directed from the left end portion on one end side in the circumferential direction to the right end portion on the other end side in the circumferential direction in FIG. It is 10a-3. Similarly, the permanent magnets 50a-3 (not shown) are adjacent to each other in the circumferential direction of the permanent magnets 50a-2, and the permanent magnets 50a-4 are adjacent to each other in the circumferential direction of the permanent magnets 50a-3.

In addition, in FIG. 15, since there are four magnetic poles per one of the permanent magnets 50a-1 to 50a-4 and four permanent magnets 50a-1 to 50a-4, the seventh modification 200 g of the rotary electric machine. The total number of magnetic poles 51a and 52a appearing in the void 1 is 16. Therefore, the rotary electric machine 200 g is a rotary electric machine having 16 magnetic poles and 12 slots 21.

In FIG. 15, the surfaces including the magnetic pole boundaries 10a-1, 10a-2, and 10a-3, which are surfaces on which the magnetic poles 51a and 52a are adjacent to each other, are designated as adjacent surfaces 24a-1, 24a-2, and 24a-3, respectively. In the armature side field core portion 22f of the rotor core 15 g, the holes 11f-1, 11f-2, 11f-3 recessed from the virtual surface 90 toward the permanent magnet 50a-1 are adjacent surfaces 24a-1 respectively. , 24a-2, 24a-3.

In FIG. 15, four magnetic poles 51a and 52a, which are a plurality of magnetic poles, are formed on one of the permanent magnets 50a-1 to 50a-4. When the total number of magnetic poles of the rotor is 16, which is the same as the total number of magnetic poles 51a and 52a in the present embodiment, the number of magnet insertion holes formed in the rotor and the number of permanent magnets are the same as the total number of magnetic poles 51a and 52a. It is assumed that the number of rotating electric machines in the fourth comparative example is 16, which is the same as the total number. Except for the number of magnet insertion holes and the number of permanent magnets, the configuration is the same as that of the rotary electric machine of the third comparative example.

In the seventh modification 200 g of the rotary electric machine of the present embodiment, the number of magnet insertion holes 19 or the permanent magnets 50a-1 to 50a-4 is 16 which is the number of permanent magnets of the rotary electric machine of the fourth comparative example. , The number of magnetic poles 51a and 52a formed in one of the permanent magnets 50a-1 to 50a-4 is four, which is the number divided by four. Therefore, the man-hours for shaping the permanent magnet 50 of the rotary electric machine 200 of the present embodiment is 1/4 of that of the rotary electric machine of the fourth comparative example. Similarly, the man-hours for magnetizing 200 g of the seventh modification of the rotary electric machine and the man-hours for inserting the permanent magnets 50a-1 to 50a-4 into the magnet insertion hole 19 are also 1/4 of those of the rotary electric machine of the fourth comparative example. become. Therefore, the manufacturing cost of the seventh modification 200 g of the rotary electric machine can be reduced as compared with the rotary electric machine of the fourth comparative example. Further, the manufacturing cost of the seventh modification 200 g of the rotary electric machine can be reduced as compared with the rotary electric machine 200 of FIG.

In FIG. 15, the number of magnetic poles 51a and 52a formed in one permanent magnet 50a-1 to 50a-4 is not limited to four poles, and may be an odd number of magnetic poles such as three poles and five poles. Further, the number of magnetic poles 51a and 52a in one permanent magnet 50a-1 to 50a-4 may be three or more.

Further, when the magnetic pole widths of the magnetic poles 51a and 52a in contact with any of the adjacent surfaces 24a-1 to 24a-3 are Wmag, g <Wh1 <Wmag or tb ≦ th1 <Wh1 / as in the first embodiment. If 2 is satisfied, the torque will increase even in the seventh modification 200 g of the rotary electric machine of the present embodiment.

Embodiment 5.
FIG. 16 is a partial cross-sectional view of an eighth modification of the electric machine according to the fifth embodiment for carrying out the present invention. In FIG. 16, the eighth modification 200h of the rotary electric machine is different from the rotary electric machine 200 according to the first embodiment in the points described below.

In FIG. 16, in the eighth modification 200h of the rotary electric machine according to the present embodiment, the permanent magnet 50b has two cylindrical surfaces 53-1 and 53-2 facing each other in the radial direction. The cylindrical surfaces 53-1 and 53-2 have a cross section including a direction from the permanent magnet 50b toward the stator 3 and a circumferential direction, that is, a cross section perpendicular to the axial direction, in the direction from the permanent magnet 50b toward the stator 3, respectively. It is convex. In the permanent magnet 50b, the surface on which the poles of the magnetic poles 51 and 52 are formed is one cylindrical surface 53-1 on the outer diameter side, that is, the stator 3 side. The radial width of the permanent magnet 50b in FIG. 16 is constant in the circumferential direction. Therefore, the radius of curvature of the cylindrical surface 53-1 on the outer diameter side is larger than the radius of curvature of the cylindrical surface 53-2 on the inner diameter side by the radial width of the permanent magnet 50b.

Since the cylindrical surfaces 53-1 and 53-2 are convex in the direction from the permanent magnet 50b toward the stator 3 in the cross section perpendicular to the axial direction, the harmonic component of the magnetic flux density waveform of the void 1 can be reduced. , The magnetic flux density waveform of the void 1 can be made close to a sine wave. Therefore, the eighth modification 200h of the rotary electric machine can reduce the torque ripple as compared with the rotary electric machine 200.

Since the permanent magnet 50b in the eighth modification 200h of the rotary electric machine has two cylindrical surfaces 53-1 and 53-2 facing each other in the radial direction, a gap is provided with the cylindrical surface 53-1 on the stator 3 side. The radial distance to 1 is shortened. Then, the radial width of the armature side field core portion 22g of the rotor core 15h can be reduced. Therefore, the magnetic resistance of the path F of the magnetic flux 20 is higher than the magnetic resistance of the path B of the magnetic flux 20 of the rotary electric machine 200. Therefore, the short circuit of the magnetic flux 20 flowing through the path F can be suppressed as compared with the case of the rotary electric machine 200 of FIG. Therefore, the eighth modification 200h of the rotary electric machine in the present embodiment can obtain a larger torque than that of the rotary electric machine 200.

In the rotor of the rotary electric machine of the present invention, the hole portions 11, 11b to 11e in FIGS. 3, 10 to 16, the notch portions 23, 23a in FIGS. 8 and 10, and the permanent magnets in FIGS. 3, 15, and 16. Any combination of 50, 50a-1 to 50a-4, 50b may be used. Even with these configurations, as in the case of the rotary electric machine 200 of the first embodiment, the torque ripple generated by the rotary electric machine is connected to the outer peripheral portion of the field core portion on the armature side on the stator side. Is reduced.

Further, when the magnetic pole width which is the width in the circumferential direction which is the direction perpendicular to the magnetizing direction corresponding to one pole of the magnetic poles 51 and 52 is Wmag, that is, in FIG. 16, one end of the magnetic poles 51 and 52 is adjacent to each other. When the magnetic pole width, which is the distance from the surface 24 to the other ends of the magnetic poles 51 and 52, is Wmag, the present implementation is performed if g <Wh1 <Wmag or tb ≦ th1 <Wh1 / 2 is satisfied as in the first embodiment. The torque also increases in the eighth modification 200h of the rotary electric machine of the above embodiment.

Embodiment 6.
FIG. 17 is a perspective view of a rotor of a ninth modification of an electric machine according to a sixth embodiment for carrying out the present invention. FIG. 18 is a cross-sectional view taken along the line GG of FIG. 17 of the ninth modification of the electric machine according to the present embodiment. Since the stator of the ninth modification 200i of the rotary electric machine, which is an electric machine in the present embodiment, is the same as the stator 3 of the rotary electric machine 200 according to the first embodiment, FIGS. 17 and 18 show rotation. The stator of the ninth modification 200i of the electric machine is not shown for convenience. In FIGS. 17 and 18, the ninth modification 200i of the rotary electric machine is different from the rotary electric machine 200 according to the first embodiment in the points described below.

In FIG. 17, the rotor core 15i in the ninth modification 200i of the rotary electric machine is arranged in a direction perpendicular to the direction from the permanent magnet 50 toward the stator 3 and the circumferential direction, that is, in a part of the axial direction. It has a first region 40 and a second region 41 arranged in an axial range different from the range of the first region 40. In the first region 40, the hole portion 11e shown in FIG. 14 of the third embodiment is arranged. In the second region 41, the rotor core 15i exists from the magnet insertion hole 19 to the virtual surface 90 at the position of the adjacent surface in the armature side field core portion 22h-2. That is, in the second region 41, no hole is formed in the armature side field iron core portion 22h-2, and the magnet insertion hole 19 to the virtual surface 90 are connected by an electromagnetic steel plate which is a magnetic material. In the rotor core 15i of FIG. 17, one second region 41 is arranged at both ends in the axial direction, and the first region is located in the central portion of the rotor 2i between the two second regions 41 in the axial direction. 40 is connected to the second region 41 to form the rotor 2i. In the rotor core 15i of FIG. 17, the sum of the axial lengths of the two second regions 41 and the axial length of the first region 40 are equal to each other.

The cross section perpendicular to the axial direction of the first region 40 is the cross section shown in FIG. The cross section perpendicular to the axial direction of the second region 41 is the cross section shown in FIG. In FIG. 18, in the armature-side field core portion 22h-2 of the second region 41, an electromagnetic steel sheet which is a magnetic material exists at the position of the adjacent surface 24 corresponding to the hole portion 11e in FIG. That is, the armature-side field iron core portion 22h-2 of the portion corresponding to the hole portion 11e is filled with an electromagnetic steel sheet. Therefore, in the armature side field iron core portion 22h-2, the magnetic flux 20 is short-circuited through the path H of the magnetic flux 20 between the magnetic pole 51 and the magnetic pole 52. Therefore, the magnetic resistance that short-circuits between the magnetic pole 51 and the magnetic pole 52 in the first region 40 due to the hole portion 11e in the first region 40 is increased as compared with the case of the second region 41.

In the ninth modification 200i of the rotary electric machine, the first region 40 having the armature side field core portion 22h-1 in which the hole portion 11e is formed and the armature side field iron core portion in which the hole portion 11e is not formed are formed. Due to the structure in which the second region 41 having 22h-2 is axially connected, the second region 41 suppresses the decrease in strength of the rotor 2i as a whole due to the centrifugal force due to the hole portion 11e in the first region 40. The short circuit of the magnetic flux 20 between the magnetic pole 51 and the magnetic pole 52 in the two regions 41 can be suppressed as compared with the case where the second region 41 is used in the first region 40 in the axial direction, and the torque of the rotor 2i as a whole is reduced. Can be suppressed. Further, by arranging the second region 41 whose strength against the centrifugal force of the rotor 2i is larger than that in the case of the first region 40 at both ends in the axial direction, both ends in the axial direction of the first region 40 can be fixed, and the rotor can be fixed. The strength of 2i against centrifugal force can be improved as compared with the case of only the first region 40.

In FIG. 18, the first region 40 in which the hole portion 11e is formed is defined as only one location in the axial direction, but the present invention is not limited to this, and the first region 40 and the second region 41 are alternately connected in the axial direction. Then, the rotor iron core 15i may be configured. In that case, the first region 40 and the second region 41 may each be composed of a stack of several electrical steel sheets. Further, the sum of the axial lengths of the two second regions 41 and the axial lengths of the first region 40 may be different depending on the required strength against centrifugal force.

FIG. 19 is a perspective view of a rotor of a tenth modification of the electric machine according to the present embodiment. In FIG. 19, the tenth modification 200j of the rotary electric machine is different from the ninth modification 200i of the rotary electric machine according to the present embodiment in the points described below.
The cross section perpendicular to the axial direction of the first region 40a is the cross section shown in FIG. 5 of the first embodiment. That is, the recess 312 shown in FIG. 5 of the first embodiment is arranged in the first region 40a. The recess 312 is formed in the armature-side field core portion 22i-1 of the rotor core 15j.
The cross section perpendicular to the axial direction of the second region 41a is the cross section shown in FIG. 3 of the first embodiment. That is, the hole portion 11 shown in FIG. 3 of the first embodiment is arranged in the second region 41a. The hole portion 11 is formed in the armature-side field core portion 22i-2 of the rotor core 15j.

In the tenth modification 200j of the rotary electric machine, the rotor 2j as a whole has a structure in which the first region 40a in which the recess 312 is arranged and the second region 41a in which the hole portion 11 is arranged are connected in the axial direction. While the decrease in strength of the rotor 2j due to the recess 312 in the 1 region 40a with respect to the centrifugal force is suppressed in the second region 41a, the increase in torque ripple in the first region 40a can be suppressed in the second region 41a. Further, by arranging the second region 41a in which the strength of the rotor 2j against the centrifugal force is larger than that in the case of the first region 40a at both ends in the axial direction, the radial direction due to the centrifugal force at both ends in the axial direction of the first region 40a is arranged. The displacement of the rotor 2j can be suppressed, and the strength of the rotor 2j against the centrifugal force can be improved as compared with the case where only the first region 40a is used.

In FIG. 19, the first region 40a in which the hole portion 11 is formed is defined as only one location in the axial direction, but the present invention is not limited to this, and the first region 40 and the second region 41a are alternately connected in the axial direction. Then, the rotor iron core 15j may be configured. In that case, the first region 40a and the second region 41a may each be configured by laminating several magnetic steel sheets. Further, the sum of the axial lengths of the two second regions 41a and the axial lengths of the first region 40a may be different depending on the required strength against centrifugal force.

The cross sections of the first regions 40, 40a and the second regions 41, 41a perpendicular to the axial direction are not limited to the cross sections shown in FIGS. 3, 5, 14, and 18, but the hole portions 11 in FIGS. 3, 10 to 16. , 11b to 11e, the cutouts 23 and 23a in FIGS. 8 and 10, and the permanent magnets 50, 50a-1 to 50a-4, 50b in FIGS. good. In the combination of these cross sections, for example, if a cross section having a high strength against centrifugal force such as FIGS. 3 and 18 is arranged at the end in the axial direction, the strength against the centrifugal force of the rotor can be improved.

Embodiment 7.
FIG. 20 is a partial cross-sectional view of an eleventh modification of the electric machine in the seventh embodiment for carrying out the present invention. In FIG. 20, the linear motion machine 200k, which is the eleventh modification of the electric machine according to the present embodiment, is different from the rotary electric machine 200 according to the first embodiment in the following points. The cross-sectional view is a cross-sectional view on a plane including the X direction in the direction along the linear movement direction of the linear motion machine 200k and the Y direction in the direction along the direction from the field magnet to the armature. In FIG. 20, the direction perpendicular to the paper surface is the Z direction.

In FIG. 20, the linear motion machine 200k in the present embodiment has a structure in which the rotary electric machine 200 of FIG. 2 is linearly developed in the X direction. Specifically, the linear motion machine 200k includes a mover 103 which is an armature and a stator 102 which is a field magnet. The mover 103 is supported by a linear guide (not shown) so as to be linearly movable. The bottom surface of the stator 102, which is a surface of the stator 102 opposite to the mover 103 side, is fixed to the upper surface of the base 109. With these configurations, the mover 103 moves linearly along the linear guide. That is, the stator 102, which is a field magnet, faces the mover 103 via the gap 101 and can move in the X direction relative to the mover 103, that is, in the X direction relative to the mover 103. It is arranged so that it can move in a straight line.

In FIG. 20, the mover 103 includes an armature core 116, which is an armature core, and six windings 106. The movable core 116 has a linear core back portion 117 and six tooth portions 118 that protrude from the core back portion 117 toward the stator 102 and are arranged at equal intervals in the linear movement direction, that is, the X direction, which is the movement direction. Have. In the movable element core 116, for the purpose of reducing the eddy current, a plurality of sheet-shaped movable element core sheets 116-1 punched from the electromagnetic steel plate in the same shape are predetermined in the Z direction perpendicular to the X direction and the Y direction. It is composed of laminated layers of length. The tooth portion 118 of the movable element core 116 is arranged so as to face the stator 102 via the gap 101. Six slots 121 are formed between the tooth portions 118 adjacent to each other in the X direction. The six windings 106 are each wound around the teeth portion 118 via the insulator 108, and are housed in the six slots 121, respectively. The winding 106 is composed of two windings 106 per phase for three phases and a total of six windings 106. Two windings 106 per phase are connected in series to form a phase winding group, and the phase winding groups for three phases are Y-connected. A magnetic field that moves linearly in the X direction is generated by energizing each phase winding group having windings 106 from an inverter 100, which is a power converter (not shown), by energizing each phase winding group with a phase shift of 120 ° between the phases. It is generated from the mover 103 to the gap 101, and a thrust in the X direction is generated in the stator 102. The connection method of the three-phase winding group is not limited to the Y connection and may be a Δ connection.

The stator 102 has a plurality of permanent magnets 150 and a stator core 115 which is a field core in which a plurality of permanent magnets 150 are embedded. The stator core 115 is configured by laminating a plurality of sheet-shaped stator core sheets 115-1 punched from an electromagnetic steel sheet in the same shape in the Z direction to a predetermined length. In the stator core 115, magnet insertion holes 119 into which the permanent magnets 150 are inserted are formed in the same number as the permanent magnets 150 and at equal intervals in the X direction. One permanent magnet 150 is inserted into each of the plurality of magnet insertion holes 119. In FIG. 20, for convenience, two permanent magnets 150 and two magnet insertion holes 119 are displayed, but the number of permanent magnets 150 is two or more, and the length of the stator 102 in the X direction is The stroke length is the length of the movable range required by the mover 103.

At both ends of the magnet insertion hole 119 in the linear movement direction, the magnetic flux short circuit between the permanent magnets 150 inserted in the magnet insertion holes 119 adjacent to each other in the linear movement direction is suppressed, and the flux barrier is a hole penetrating in the Z direction. 107 is provided. A non-magnetic material such as a resin may be inserted into the flux barrier 107.

In the permanent magnet 150, magnetic poles 151 and 152 having different poles on the armature 103 side are formed adjacent to each other in the X direction. That is, in FIG. 1, the magnetic pole 151 is magnetized so as to have an N pole on the surface on the mover 103 side, and the magnetic pole 152 is magnetized so as to have an S pole on the surface on the mover 103 side. The north pole of the magnetic pole 151 is formed on the surface on the mover 103 side on one side in the X direction from the central portion of the permanent magnet 150. The pole of the S pole of the magnetic pole 152 is formed on the surface on the mover 103 side on the other side in the X direction from the central portion of the permanent magnet 150. The surface where the magnetic poles 151 and 152 are adjacent to each other in the X direction is the magnetic pole boundary 110. Here, the definition of the magnetic pole boundary 110 is the same except that the circumferential direction in the first embodiment is replaced with the X direction. Further, the permanent magnet 150 has the same flat plate shape as the permanent magnet 1 of FIG. 3 of the first embodiment.
In FIG. 20, the linear motivator 200k is a linear motivator having two or more magnetic poles 151 and 152 and six slots 121. Further, the number of magnetic poles 151 and 152 facing the X-direction range of the mover 103 of the linear moving machine 200k is four.

In FIG. 20, the stator core 115 located on the mover 103 side of the permanent magnet 150 is referred to as the armature side field core portion 122. A surface separated from the mover 103 toward the stator core 115 at a distance equal to the minimum length g of the gap 101 is referred to as a virtual surface 190. In FIG. 20, in the virtual surface 190, the surface including the magnetic pole boundary 110, which is a surface on which the magnetic poles 151 and 152 are adjacent to each other, is referred to as an adjacent surface 124. In the armature side field iron core portion 122, a hole portion 111 recessed from the virtual surface 190 toward the permanent magnet 150 is formed at the position of the adjacent surface 124. Here, the minimum length g of the gap 101 represents the minimum distance between the teeth portion 118 of the movable core 116 and the stator core 115 in the Y direction. The boundary of the armature-side field core portion 122 is a portion of the stator core 115 having a minimum width tb in the direction from the end of the permanent magnet 150 in the X direction toward the mover 103. In FIG. 20, the virtual surface 190 is a plane separated from the mover 103 toward the stator core 115 with the minimum length g of the gap 101. In FIG. 20, the virtual surface 190 coincides with the surface of the stator core 115 on the movable element 103 side.

The hole portion 111 is formed in the armature side field iron core portion 122 so as to straddle the adjacent surface 124 in the X direction. The cross-sectional shape of the hole 111 in the cross section perpendicular to the Z direction is a wedge shape in which the width in the X direction is narrowed in the Y direction toward the permanent magnet 150 side from the virtual surface 190 and becomes convex.

With these configurations, as in the case of the rotary electric machine 200 of the first embodiment, the thrust ripple of the linear motion machine 200k of the present embodiment of FIG. 20 is the outer peripheral portion of the field core portion on the armature side on the mover side. Is reduced compared to when is concatenated.

In FIG. 20, in addition to the hole portion 111, a notch portion 123 is provided between adjacent permanent magnets 150 on the outer peripheral portion of the stator core 115. That is, the notch 123 recessed from the virtual surface 190 in the direction from the mover 103 toward the stator core 115 is located at the center of the stator core 115 between the permanent magnets 150 adjacent to each other in the X direction in the X direction. It is formed at the position of the central surface 125, which is the surface to be magnetized.

Further, in FIG. 20, in the range of the X direction occupied by the hole portion 111, the permanent portion of the field core portion 122 on the armature side facing one of the magnetic poles 151 in the Y direction, which is the direction from the permanent magnet 150 toward the mover 103. The maximum distance in the Y direction from the magnet 150 and the maximum distance in the Y direction from the permanent magnet 150 at the armature side field core portion 122 facing the other magnetic pole 152 adjacent to one magnetic pole 151. The opening width, which is the length of the straight line connecting the points, is Wh8, and the width in the moving direction, that is, the width in the X direction, which is the direction perpendicular to the magnetizing direction corresponding to one pole of the magnetic pole 151 or the magnetic pole 152 of the permanent magnet 150. Let Wmag be the magnetic pole width. At this time, it is desirable that the opening width Wh8 is set to be smaller than the magnetic pole width Wmag and larger than the minimum length g of the gap 101. That is, it is desirable that g <Wh8 <Wmag.

Further, in FIG. 20, the width in the Y direction, which is the direction from the permanent magnet 150 toward the mover 103 at the position of the adjacent surface 124 in the armature side field core portion 122, is set to th6, and the armature side field core portion 122 Let tb be the minimum width in the direction from the end of the permanent magnet 150 in the X direction toward the mover 103. Further, the portion of the stator core 115 including the portion having the width th6 in the armature side field core portion 122 and the same range as the X direction range of the hole portion 111 is used as the first bridge portion, that is, the thin-walled portion 113, and th6 is used. The width of the thin portion 113 is set. Further, the mover 103 side of the flux barrier 107 from the portion having the minimum width tb at the boundary of the armature side field core portion 122 to the minimum width tb of the boundary of the armature side field iron core portion 122 adjacent to each other in the X direction. The portion of the stator core 115 located at is referred to as the second bridge portion 126.

In order to cause magnetic saturation in the thin-walled portion 113, it is desirable to set the width th6 of the thin-walled portion 113 as small as possible. That is, it is desirable that the width th6 of the thin portion 113 is tb ≦ th6 <Wh8 / 2 with respect to the minimum width tb and the opening width Wh8. This is because it is necessary to set the lower limit of the width th6 of the thin-walled portion 113 to the minimum width tb of the dimension capable of punching the electromagnetic steel sheet. Further, when th6 <Wh8 / 2, the amount of the magnetic flux passing through the width th6 of the thin wall portion 113 among the magnetic flux 120 flowing through the magnetic pole 151 and the magnetic pole 152 is larger than the amount of the magnetic flux flowing from the opening width Wh8 to the void 101. This is because it also becomes smaller. Due to this dimensional relationship, the magnetic flux 120 generated by the permanent magnet 150 or the magnetic flux generated by the mover 103 tends to cause magnetic saturation in the thin portion 113. When magnetic saturation occurs in the thin-walled portion 113, the relative magnetic permeability of the thin-walled portion 113 becomes close to that of air. Therefore, the thrust generated by the linear motion machine 200k can be further increased.

It should be noted that g <Wh8 <Wmag and tb ≦ th6 <Wh8 / 2 are dimensions that can be set individually, and the effect of increasing thrust is also exhibited in each. Further, if g <Wh8 <Wmag and tb ≦ th6 <Wh8 / 2, the thrust is increased as compared with the case of setting any of the dimensional relationships.

FIG. 21 is a partial cross-sectional view of a twelfth modification of the electric machine according to the present embodiment. In FIG. 21, the linear moving machine 200m, which is the twelfth modification of the electric machine according to the present embodiment, is different from the linear moving machine 200k according to the present embodiment in the points described below.
In FIG. 21, the hole portion 111a penetrates from the gap 101 to the magnet insertion hole 119. Assuming that the opening width of the hole portion 111a is Wh9, the hole portion 111 penetrates from the gap 101 to the magnet insertion hole 119 with the width of the opening width Wh9.

When the opening width Wh9 of the hole portion 111a in FIG. 21 is the same as the opening width Wh8 of the hole portion 111 of the linear motion machine 200k, the magnetic resistance through which the magnetic flux 120 passes through the opening width Wh9 is higher than the magnetic resistance of the thin-walled portion 113 of the linear motion machine 200k. Will also increase. Therefore, in the linear motion machine 200 m, the magnetic flux 120 flowing from the armature side field core portion 122a of the stator core 115a to the mover 103 leaks to the opening width Wh9, as compared with the case where the magnetic flux 120 leaks to the thin wall portion 113 in the linear motion machine 200k. Can be suppressed. Therefore, as in the case of the third embodiment, the thrust generated by the linear moving machine 200m is increased as compared with the case of the linear moving machine 200k.

In the present embodiment, the mover 103 is a linear motor that is a linear motor with a permanent magnet 150 as a field, but the mover 103 is a stator and the stators 102 and 102a are stators. It may be a magnet movable type linear motor which is a mover which moves with respect to. Further, the winding 106 may be arranged on the stators 102 and 102a instead of the mover 103.

The cross-sectional shape of the hole 111 in the cross section perpendicular to the Z direction is not limited to the cross sections shown in FIGS. 20 and 21, but the holes 11 and 11b to 11e in FIGS. The cross section may be an arbitrary combination of the notched portions 23, 23a and the permanent magnets 50, 50a-1 to 50a-4, 50b in FIGS. 3, 15 and 16. Even with these configurations, as in the case of the linear motion machine 200k of the present embodiment of FIG. 20, the thrust ripple is higher than that in the case where the outer peripheral portion of the armature side field core portion on the armature side is connected. It will be reduced.

Further, as in the ninth modification 200i and the tenth modification 200j of the rotary electric machine of the sixth embodiment, the cross section of the stator cores 122 and 122a in the linear motion machine 200k and 200m of the present embodiment is perpendicular to the Z direction. A combination of two or more cross sections in which any one of the holes 11 to 11 g in FIGS. 3, 4, 8 to 13, 15, 16 and 18 is formed in the armature side field core portions 122 and 122a in the Z direction. It may be laminated and configured.

1, 101, 301 voids, 2, 2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h, 2i, 2j, 302 rotor (field), 3,303 stator (armature), 4 support shafts , 5 bearings, 6, 106, 306 windings, 7, 107, 307 flux barriers, 8, 108, 308 insulators, 9 housings, 10, 10-1, 10-2, 10a-1, 10a-2, 10a- 3, 110, 310 Magnetic pole boundaries, 11, 11-1, 11-2, 11a, 11b, 11c, 11d, 11e, 11f-1, 11f-2, 11f-3, 11g, 111, 111a Holes, through holes Part (hole part), 12, 312 concave part, 13, 13a, 13b, 13c, 13d, 113, 313 Thin-walled part (first bridge part), 15, 15a, 15b, 15c, 15d, 15e, 15f, 15g, 15h , 15i, 15j, 315 rotor core (field core), 15-1 rotor core sheet, 16, 316 stator core (armature core), 16-1 stator core sheet, 17, 117 core back part, 18, 118, 318 Teeth part, 19, 19a, 119, 319 Magnet insertion hole, 20, 120, 320 magnetic flux, 21, 121 slots, 22, 22-1, 22-2, 22a-1, 22a-2, 22b , 22c, 22d, 22e, 22f, 22g, 22h-1, 22h-2, 22i-1, 22i-2, 122, 122a, 322 Armature side field core, 23, 23a, 123 Notch, 24 , 124, 24-1, 24-2, 24a-1, 24a-2, 24a-3, 324 Adjacent surface, 25, 325 Central surface, 26, 26a, 126, 326 Second bridge part, 30a-1, 30a -2, 30b-1, 30b-2 Projections (first protrusion, second protrusion), 40, 40a 1st region, 41, 41a 2nd region, 50, 50-1, 50-2, 50a-1, 50a-2, 50a-3, 50a-4, 50b, 150, 350 Permanent magnets, 51, 51-1, 51-2, 51a, 52, 52-1, 52-2, 52a, 151, 152, 351, 352 magnetic poles (first magnetic pole, second magnetic pole), 53-1, 53-2 Cylindrical plane, 90, 190 virtual plane, 100 Inverter (power converter), 102, 102a Stator (field), 103 Movable machine (machine), 109 base, 115, 115a Stator core (field core), 115-1, 115a-1 stator Iron core sheet, 116 Movable core (armor core), 116-1 Movable core sheet, 200, 200a, 200b, 200c, 200d, 200e, 200f, 200g, 200h, 200i, 200j Rotating electric machine (electric machine), 200k , 200m linear motion machine (electric machine), 300 rotary electric machine (electric machine) first comparative example, 500 drive system.

Claims (17)

With an armature
A field magnet that faces the armature through a gap and is movably arranged relative to the armature, and magnetic poles having different poles on the armature side are formed adjacent to each other in the moving direction. The permanent magnet is provided with a field magnet having a field core in which the permanent magnet is embedded.
When a surface separated from the armature in the direction toward the field core at a distance equal to the minimum length of the gap is used as a virtual surface.
In the armature-side field iron core portion, which is the field iron core located on the armature side of the permanent magnet, the hole portion recessed from the virtual surface toward the permanent magnet is a surface on which the magnetic poles are adjacent to each other. An electric machine formed at the position of the adjacent surface including. The field has a plurality of the permanent magnets.
In the field core, a notch portion recessed from the virtual surface in the direction from the armature toward the field core is located at the center of the moving direction between the permanent magnets adjacent to each other in the moving direction. The electric machine according to claim 1, which is formed at a surface position. When the permanent magnets adjacent to each other in the moving direction across the notch portion are used as the first permanent magnet and the second permanent magnet.
The first hole is located in the armature-side field core at the position of the adjacent surface including one end surface in the circumferential direction of the first magnetic pole closest to the notch in the first permanent magnet. Is formed and
In the field iron core, a first protruding portion protruding from the first permanent magnet toward the armature is formed between the first hole portion and the notch portion.
The second hole is located in the armature-side field core at the position of the adjacent surface including one end surface in the circumferential direction of the second magnetic pole closest to the notch in the second permanent magnet. Is formed and
2. Claim 2 in which, in the field iron core, a second protruding portion is formed between the second hole portion and the notch portion so as to project from the second permanent magnet toward the armature. The electric machine described in. The electric machine according to claim 3, wherein the radius of curvature of the first protrusion and the radius of curvature of the second protrusion are each smaller than the radius of curvature of the virtual surface. In the field core portion on the armature side, a bridge portion is formed in which the positions of the adjacent surfaces are arranged so as to straddle the moving direction.
The electric machine according to any one of claims 1 to 4, wherein the width of the bridge portion in the direction from the permanent magnet to the armature is constant in the moving direction. The magnetic pole width, which is the width of the magnetic pole of the permanent magnet in the moving direction, is Wmag, the minimum length of the gap is g, and the direction from the permanent magnet to the armature within the range of the moving direction occupied by the hole. , The point where the distance from the permanent magnet at the armature side field core portion facing one of the magnetic poles is maximum, and the armature side field core portion facing the other magnetic pole adjacent to the one magnetic pole. The opening width, which is the length of the straight line connecting the point where the distance from the permanent magnet is maximum, is Wh, and the permanent magnet at the position of the adjacent surface in the armature side field core portion is directed toward the armature. When the width in the direction is th, and the minimum width in the direction from the end of the permanent magnet in the moving direction to the armature in the armature side field core portion is tb.
The electric machine according to any one of claims 1 to 5, wherein g <Wh <Wmag, or tb ≦ th <Wh / 2. A magnet insertion hole in which the permanent magnet is embedded is formed in the field iron core.
The present invention according to any one of claims 1 to 5, wherein in the armature side field iron core portion, a recess recessed from the magnet insertion hole toward the armature side is formed at the position of the adjacent surface. The described electric machine. A magnet insertion hole in which the permanent magnet is embedded is formed in the field iron core.
The electric machine according to any one of claims 1 to 4, wherein the hole portion penetrates from the gap to the magnet insertion hole. The electric machine according to any one of claims 1 to 8, wherein the number of the magnetic poles in the permanent magnet is 3 or more. The electric machine according to any one of claims 1 to 9, wherein the permanent magnet is composed of one magnetic material having a plurality of the magnetic poles. The electric machine according to any one of claims 1 to 9, wherein the permanent magnet is composed of a plurality of magnetic materials divided for each magnetic pole. The permanent magnet has two planes facing each other and has two planes facing each other.
The electric machine according to any one of claims 1 to 11, wherein the surface of the permanent magnet on which the pole of the magnetic pole is formed is one of the planes. The permanent magnet has two cylindrical surfaces facing each other.
The cylindrical surface is convex in the direction from the permanent magnet to the armature in a cross section including the direction from the permanent magnet toward the armature and the moving direction.
The electric machine according to any one of claims 1 to 11, wherein the surface of the permanent magnet on which the pole of the magnetic pole is formed is one of the cylindrical surfaces. The field core has a first region arranged in a partial range and a range different from the range of the first region in the direction from the permanent magnet toward the armature and the direction perpendicular to the moving direction. It has a second area arranged and
The hole is arranged in the first region.
The electric machine according to claim 7, wherein the recess is arranged in the second region. The field core has a first region arranged in a partial range and a range different from the range of the first region in the direction from the permanent magnet toward the armature and the direction perpendicular to the moving direction. It has a second area arranged and
The hole is arranged in the first region.
The electric machine according to claim 8, wherein in the second region, the field core exists from the magnet insertion hole to the virtual surface at the position of the adjacent surface in the armature side field core portion. The electric machine according to any one of claims 1 to 15, wherein the field is rotationally moved relative to the armature in the moving direction about an axis. The electric machine according to any one of claims 1 to 15, wherein the field moves linearly with respect to the armature in the moving direction.

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