JP2017121153A - motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor capable of achieving high-speed rotation while suppressing the reduction in torque.SOLUTION: A rotor 21 includes: magnet magnetic poles Mn, Ms comprising permanent magnets 22; and a non-magnet magnetic pole section 25 of a rotor core 23 which opposes U-phase windings U2, U4 at a rotational position of the rotor 21 where the magnet magnetic pole Mn (or the magnet magnetic pole Ms) opposes, for example, U-phase windings U1, U3. The non-magnet magnetic pole section 25 of the rotor core 23 includes: core magnetic poles Cn, Cs that function as an opposing magnetic pole to the magnet magnetic poles Mn, Ms by the magnetic fluxes of the magnet magnetic poles Mn, Ms; and a core section 28 between slits (magnetic flux permitting section) which permits the generation of an interlinkage magnetic flux (weak field magnetic flux) arising as a result of a weak field current in an opposing windings 13.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a motor.

  Conventionally, a permanent magnet motor such as a brushless motor includes, for example, a stator in which a winding is wound around a stator core and a rotor having a permanent magnet facing the stator as a magnetic pole, as shown in Patent Document 1, for example. The rotor rotates by receiving a rotating magnetic field generated by supplying a drive current to the winding of the stator.

JP 2014-135852 A

  In the permanent magnet motor as described above, the higher the rotor is driven, the greater the induced voltage generated in the stator winding due to the increase of the linkage flux by the permanent magnet of the rotor, and this induced voltage decreases the motor output. This hinders high motor rotation. Therefore, by reducing the magnetic force of the rotor magnetic poles, for example, by reducing the size of the permanent magnets of the rotor, it is possible to suppress the induced voltage when the rotor rotates at a high speed. Therefore, there is still room for improvement in this respect.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a motor capable of achieving high rotation speed while suppressing a decrease in torque.

  A motor that solves the above problem is a motor in which a rotor rotates in response to a rotating magnetic field generated by supplying a drive current to a winding of a stator, and the windings are rotated at the same timing by the drive current. The rotor includes a first winding and a second winding that are excited and connected in series, and the rotor includes a magnetic pole having a permanent magnet and a part of a rotor core, and the magnetic pole is the first winding. A core magnetic pole that opposes the second winding at a rotational position of the rotor that faces the first winding, and a part of the rotor core, wherein the magnet magnetic pole is at a rotational position of the rotor that faces the first winding. There is provided a magnetic flux allowing portion facing the second winding and allowing the generation of the linkage magnetic flux by the field weakening current in the second winding.

  According to this configuration, at the rotational position where the magnet magnetic pole of the rotor faces the first winding, the non-magnet magnetic pole portion (at least one of the core magnetic pole and the magnetic flux allowing portion) other than the magnet magnetic pole in the rotor core is the second winding. It is comprised so that it may oppose. As a result, the combined induced voltage obtained by combining the induced voltages generated in the first and second windings can be kept small, and as a result, the motor can be rotated at a high speed.

  Here, considering a configuration in which all the non-magnetic magnetic pole portions of the rotor core are core magnetic poles, although the torque can be gained, the magnetic force of the core magnetic poles weakens the generation of the interlinkage magnetic flux (weak field magnetic flux) due to the field current weakening. Therefore, it is disadvantageous for high rotation. Therefore, in this configuration, not all the non-magnet magnetic pole portions of the rotor core are used as core magnetic poles, but the non-magnet magnetic pole portions are provided with both a magnetic flux allowing portion and a core magnetic pole that allow generation of field-weakening magnetic flux. Thus, it is possible to increase the rotation speed while suppressing the decrease in torque as much as possible.

  In the winding mode in which the first and second windings excited at the same timing are connected in series, the sum of the induced voltages generated in the first and second windings becomes the combined induced voltage. The synthetic induced voltage tends to increase. For this reason, by using the above-described rotor configuration in the configuration in which the first and second windings are connected in series, the effect of suppressing the combined induction voltage can be obtained more significantly, and the motor can be rotated at a higher speed. It becomes more suitable.

  In the motor, the magnet magnetic pole and the core magnetic pole are respectively provided in both the N pole and the S pole of the rotor, and the magnetic flux allowing portion is configured such that the core magnetic pole and the S pole of the N pole in the circumferential direction of the rotor. Preferably, each of the N and S core magnetic poles provided between the core magnetic poles is adjacent to the magnet poles having different polarities on the opposite side to the magnetic flux allowing portion in the circumferential direction.

  According to this configuration, since the core magnetic pole is interposed between the magnetic flux allowing portion and the magnet magnetic pole in the circumferential direction, the magnetic flux allowing portion can be made less susceptible to the magnetic flux of the magnet magnetic pole. As a result, the magnetic flux allowing portion allows the generation of the field weakening magnetic flux to be more suitable.

  In the motor, it is preferable that an opening angle of a surface of the magnet magnetic pole facing the stator is set larger than an opening angle of the core magnetic pole facing the stator.

  According to this configuration, since the opening angle of the magnet magnetic pole is set larger than the opening angle of the core magnetic pole, the magnetic force of the magnet magnetic pole and the magnetic force of the core magnetic pole functioning as a pseudo magnetic pole are secured by the magnetic flux of the magnet magnetic pole. And a decrease in torque can be suppressed more suitably.

  In the motor, it is preferable that an opening angle of a surface facing the stator in the magnetic flux allowing portion is set larger than an opening angle of a surface facing the stator in the core magnetic pole.

According to this configuration, the opening angle of the magnetic flux allowing portion that allows generation of the field weakening magnetic flux is set to be larger than the opening angle of the core magnetic pole, so that a configuration suitable for higher rotation can be achieved.
In the motor, it is preferable that the rotor core includes a magnetoresistive portion between the magnetic flux allowing portion and the core magnetic pole adjacent to each other.

  According to this configuration, the rotor core includes the magnetoresistive portion between the adjacent magnetic flux allowing portion and the core magnetic pole, so that the magnetic flux of the magnet magnetic pole passing through the core magnetic pole can be prevented from flowing to the magnetic flux allowing portion.

In the motor, it is preferable that the magnetoresistive portion is a slit portion provided in the rotor core.
According to this configuration, since the magnetoresistive portion is the slit portion, the magnetoresistive portion can be easily configured in the rotor core.

In the motor, it is preferable that an auxiliary magnet is provided in the slit portion.
According to this configuration, the amount of magnetic flux of the core magnetic pole can be increased by the auxiliary magnet in the slit portion, and a reduction in torque can be more suitably suppressed.

In the motor, it is preferable that an auxiliary magnet for flowing a magnetic flux through the core magnetic pole is embedded in a portion radially inward of the magnetic flux allowing portion in the rotor core.
According to this configuration, the amount of magnetic flux of the core magnetic pole can be increased by the auxiliary magnet disposed radially inward of the magnetic flux allowing portion, and a decrease in torque can be more suitably suppressed.

  In the motor, the rotor core includes the core body having the magnet magnetic pole and the core magnetic pole, and a separate core member that is connected to the core body and forms at least a part of the magnetic flux allowing portion. It is preferable to provide.

  According to this configuration, since the core main body having the magnetic pole and the core magnetic pole and the separate core member constituting at least a part of the magnetic flux allowing portion are configured separately from each other, the field weakening in the separate core member Interference between the magnetic path of the magnetic flux and the magnetic path of the magnetic pole of the magnet magnetic pole in the core body can be suppressed. Thereby, the field-weakening magnetic flux can easily pass through the separate core member (magnetic flux allowing portion), thereby contributing to further increase in the rotation speed of the motor.

In the motor, the separate core member is preferably made of a material having a higher magnetic permeability than the core body.
According to this configuration, the field-weakening magnetic flux can be more easily passed through the separate core member (magnetic flux allowing portion), and as a result, the motor can be further increased in rotation. Further, in the constituent parts of the rotor core, at least the separate core member is made of a material with high magnetic permeability, and the core body is made of an inexpensive material, so that the rotation speed can be increased while suppressing an increase in manufacturing cost. .

  In the motor, the magnet magnetic pole and the core magnetic pole included in the core main body are provided in both the N pole and the S pole of the rotor, respectively, and the separate core member that constitutes the magnetic flux allowing portion is the rotor of the rotor. Provided between the core pole of N pole and the core pole of S pole in the circumferential direction, and the core poles of N pole and S pole are different on the opposite side from the separate core member in the circumferential direction. It is preferably configured to be adjacent to the magnetic pole of the pole, and a gap is provided between the separate core member in the circumferential direction and the core magnetic pole of the N pole and the S pole.

  According to this configuration, the core magnetic pole is interposed between the circumferential direction of the separate magnetic core member and the magnetic magnetic pole constituting the magnetic flux allowing portion, and therefore the separate core member is less susceptible to the magnetic flux of the magnetic magnetic pole. can do. That is, the interference of the magnetic flux of the magnet magnetic pole with the field weakening magnetic flux passing through the separate core member can be further suppressed. In addition, since gaps are provided between the separate core member in the circumferential direction and the N pole and S pole core magnetic poles, interference of the magnetic flux of the magnetic pole with the field weakening magnetic flux passing through the separate core member is further suppressed. it can.

  In the motor, it is preferable that the core body and the separate core member are connected to each other via a connection member made of a material having a larger magnetic resistance than the core body and the separate core member.

  According to this configuration, the connecting member that connects the core body and the separate core member is made of a material having a larger magnetic resistance than the core body and the separate core member. For this reason, the magnetic flux of the magnetic pole of the core body can be prevented from flowing to the separate core member side through the connecting member, and as a result, the interference of the magnetic flux of the magnetic pole with the field weakening magnetic flux passing through the separate core member is further suppressed. it can.

  According to the motor of the present invention, high rotation can be achieved while suppressing a decrease in torque.

(A) is a top view of the motor of embodiment, (b) is a top view of the rotor of the same form. (A) (b) It is explanatory drawing for demonstrating the magnetic effect | action at the time of the field weakening control in the motor of the same form. It is a top view of the rotor of another example. It is a top view of the rotor of another example. It is a top view of the rotor of another example. It is a top view of the rotor of another example. It is a top view of the rotor of another example. It is a top view of the rotor of another example. It is a top view of the rotor of another example. It is a top view of the rotor of another example.

Hereinafter, an embodiment of the motor will be described.
As shown in FIG. 1A, the motor 10 of the present embodiment is configured as a brushless motor, and is configured by arranging a rotor 21 inside an annular stator 11.

[Structure of stator]
The stator 11 includes a stator core 12 and a winding 13 wound around the stator core 12. The stator core 12 is formed of a magnetic metal in a substantially annular shape, and has twelve teeth 12a extending radially inward at equal angular intervals in the circumferential direction.

  Twelve windings 13 are provided in the same number as the teeth 12a, and are wound around the teeth 12a in the same direction by concentrated winding. That is, twelve windings 13 are provided at equal intervals in the circumferential direction (30 ° intervals). The windings 13 are classified into three phases according to the three-phase driving currents (U phase, V phase, W phase) supplied, and U1, V1, Let W1, U2, V2, W2, U3, V3, W3, U4, V4, and W4.

  When viewed in each phase, the U-phase windings U1 to U4 are arranged at equal intervals in the circumferential direction (90 ° intervals). Similarly, the V-phase windings V1 to V4 are arranged at equal intervals in the circumferential direction (90 ° intervals). Similarly, the W-phase windings W1 to W4 are arranged at equal intervals in the circumferential direction (90 ° intervals).

  Further, the winding 13 is connected in series for each phase. That is, the U-phase windings U1 to U4, the V-phase windings V1 to V4, and the W-phase windings W1 to W4 each constitute a series circuit. The series circuit of the U-phase windings U1 to U4, the series circuit of the V-phase windings V1 to V4, and the series circuit of the W-phase windings W1 to W4 are star-connected or delta-connected.

[Configuration of rotor]
As shown in FIG. 1B, the rotor 21 has an embedded magnet type structure (IPM structure) in which a permanent magnet 22 that forms a magnetic pole is embedded in a rotor core 23. The rotor core 23 is formed in a cylindrical shape by laminating a plurality of core sheets made of a circular plate-shaped magnetic metal in the axial direction, and a rotating shaft 24 is inserted and fixed at the center of the rotor core 23. A fixing hole 23a is formed.

  The rotor 21 is configured as an 8-pole rotor in which N poles and S poles are alternately set on the outer peripheral surface 23 b of the rotor core 23. Specifically, the rotor 21 includes a pair of N-pole magnet magnetic pole Mn, S-pole magnet magnetic pole Ms, N-pole core magnetic pole Cn, and S-pole core magnetic pole Cs. Each of the magnetic poles Mn and Ms is a magnetic pole using the permanent magnet 22, and each of the core magnetic poles Cn and Cs is a magnetic pole using a part of the rotor core 23.

  Each of the magnetic poles Mn and Ms of the N pole and the S pole includes a pair of permanent magnets 22 embedded in the rotor core 23, respectively. In each of the magnetic poles Mn and Ms, the pair of permanent magnets 22 is arranged in a substantially V shape that expands to the outer peripheral side when viewed in the axial direction, and a magnetic pole center line in the circumferential direction (straight line L1 in FIG. 1B). For reference). Each permanent magnet 22 has a rectangular parallelepiped shape. The pair of permanent magnets 22 in each of the magnetic poles Mn and Ms is equally divided by the number of poles in the circumferential direction of the rotor 21 (the total number of the magnetic poles Mn and Ms and the core magnetic poles Cn and Cs, 8 in this embodiment). It is arranged so that it falls within the angle range (45 ° range in this embodiment). Each permanent magnet 22 is, for example, an anisotropic sintered magnet, and is composed of, for example, a neodymium magnet, a samarium cobalt (SmCo) magnet, an SmFeN-based magnet, a ferrite magnet, an alnico magnet, or the like.

  In FIG. 1B, the magnetization directions of the permanent magnets 22 of the N-pole magnet magnetic pole Mn and the S-pole magnet magnetic pole Ms are indicated by solid arrows, and the tip end side of the arrow is the N pole and the base end side of the arrow is the S pole. Represents. As indicated by the arrows, the permanent magnets 22 in the N-pole magnet magnetic pole Mn have N faces on the surfaces facing each other (the face on the magnetic pole center line side) so that the outer peripheral side of the magnet magnetic pole Mn becomes the N-pole. Magnetized so that poles appear. In addition, each permanent magnet 22 in the magnetic pole Ms of S pole is magnetized so that the S pole appears on the surfaces facing each other (surface on the side of the magnetic pole center line) so that the outer peripheral side of the magnet magnetic pole Ms becomes the S pole. ing.

  The N-pole magnet magnetic pole Mn and the S-pole magnet magnetic pole Ms are arranged adjacent to each other so that the distance between the circumferential center positions (magnetic pole centers) is 45 °. A pair of the magnetic pole Mn and the magnetic pole Ms of the S pole is referred to as a magnetic pole pair P. And in the rotor 21 of this embodiment, two magnet magnetic pole pairs P are provided in the 180 degree opposing position of the circumferential direction. More specifically, the N-pole magnetic pole Mn of one magnet pole pair P and the N-pole magnet pole Mn of the other magnet pole pair P are disposed at positions opposite to each other by 180 °. The S-pole magnet magnetic pole Ms of the pair P and the S-pole magnet magnetic pole Ms of the other magnet magnetic pole pair P are arranged at 180 ° opposite positions. That is, the magnetic poles Mn and Ms (permanent magnets 22) are provided so as to be point-symmetric about the axis L of the rotor 21 (the axis of the rotating shaft 24).

  Further, the opening angle θm (occupied angle) around the axis L of the magnet magnetic poles Mn and Ms is set to an angle (45 ° in this embodiment) obtained by equally dividing the rotor 21 by the number of poles in the circumferential direction. . That is, the opening angle of each magnetic pole pair P composed of the magnetic poles Mn and Ms adjacent in the circumferential direction is approximately 90 °.

  Here, in the circumferential direction of the rotor core 23, the occupation angle of the pair of magnet magnetic pole pairs P is approximately 180 °, and the remaining range is a portion where the magnet is not disposed (non-magnet magnetic pole portion 25). That is, in the rotor core 23, a pair of magnet magnetic pole pairs P and a pair of non-magnet magnetic pole portions 25 are alternately configured approximately every 90 ° in the circumferential direction.

  Each non-magnet magnetic pole portion 25 is provided with a pair of slit portions 26a and 26b as magnetic resistance portions. In this embodiment, each slit part 26a, 26b is extended from the position near the fixing hole 23a of the rotor core 23 to the position near the outer peripheral surface 23b of the rotor core 23 along the radial direction. Moreover, each slit part 26a, 26b is a hole which penetrates the rotor core 23 to an axial direction.

  In each non-magnet magnetic pole portion 25, the pair of slit portions 26 a and 26 b are formed so as to be line symmetric with respect to the circumferential center line L <b> 2 of the non-magnet magnetic pole portion 25. The N pole magnetic pole Mn side with respect to the circumferential center line L2 is the slit portion 26a, and the S pole magnet magnetic pole Ms side is the slit portion 26b. In the present embodiment, in the circumferential direction of the rotor 21, the angle formed by the circumferential center line L2 and the slit portions 26a, 26b is set to approximately 25 °. That is, in each non-magnet magnetic pole portion 25, the angle in the circumferential direction formed by the pair of slit portions 26a and 26b is set to about 50 °. Thus, it is preferable that the angle formed by the pair of slit portions 26a and 26b of the non-magnet magnetic pole portion 25 is set to a half or more of the open angle of the non-magnet magnetic pole portion 25 (approximately 90 ° in the present embodiment). The angle formed by the circumferential center line L2 of the non-magnet magnetic pole portion 25 and the circumferential center line L3 of the magnet magnetic pole pair P (boundary line between the adjacent magnet magnetic poles Mn and Ms) is 90 °.

  Further, the rotor core 23 is formed with a magnetoresistive hole 27 at a position on the inner peripheral side with respect to the pair of permanent magnets 22 in each of the magnetic poles Mn and Ms. Each magnetoresistive hole 27 is a rectangular hole that is long in the radial direction when viewed in the axial direction, and is provided at the center position in the circumferential direction of each magnet magnetic pole Mn, Ms. That is, in the present embodiment, the distance between the centers of the magnetoresistive holes 27 of the magnet magnetic poles Mn and Ms adjacent in the circumferential direction is set to 45 °. Each magnetoresistive hole 27 penetrates the rotor core 23 in the axial direction.

  Further, gaps K1 and K2 are provided on the inner peripheral side and the outer peripheral side of each permanent magnet 22, respectively. Each gap K1, K2 is a part of each magnet accommodation hole 23c formed in the rotor core 23 for accommodating each permanent magnet 22, and the inner circumferential side surface of each permanent magnet 22 faces each gap K1, The inner circumferential side surface of each permanent magnet 22 is configured to face each gap K2. That is, a gap K1 is provided between the permanent magnet 22 and the radially inner end of the magnet accommodation hole 23c, and a gap K2 is provided between the permanent magnet 22 and the radially outer end of the magnet accommodation hole 23c. Yes.

  Each magnetic resistance hole 27 suppresses a short circuit of the magnetic flux between the magnet magnetic poles Mn and Ms in each magnet magnetic pole pair P, and suppresses a short circuit of the magnetic flux in each of the permanent magnets 22 by each of the gaps K1 and K2. Is done. As a result, the magnetic flux (magnet magnetic flux) of the permanent magnet 22 of each magnet magnetic pole Mn, Ms is efficiently induced to the outer peripheral side of the magnet magnetic pole Mn, Ms and the non-magnetic magnetic pole part 25 side in the circumferential direction. It has become.

  Here, each non-magnet magnetic pole portion 25 of the rotor core 23 is divided into three regions by a pair of slit portions 26a and 26b, and the region adjacent to the N-pole magnet magnetic pole Mn in the circumferential direction (the magnet of the slit portion 26a). The region on the magnetic pole Mn side) is configured as an S-pole core magnetic pole Cs. A region adjacent to the S-pole magnet magnetic pole Ms in the circumferential direction (region on the magnet magnetic pole Ms side of the slit portion 26b) is configured as an N-pole core magnetic pole Cn.

  More specifically, magnet magnetic flux flowing from the N-pole magnet magnetic pole Mn to the circumferential non-magnet magnetic pole part 25 side (side not adjacent to the magnet magnetic pole Ms) is moved to the outer peripheral surface 23b side of the rotor core 23 by the magnetic resistance of the slit part 26a. Be guided. As a result, the region adjacent to the N-pole magnet magnetic pole Mn in the non-magnet magnetic pole portion 25 functions as the S-pole core magnetic pole Cs (pseudo-magnetic pole) by the magnet magnetic flux of the magnet magnetic pole Mn.

  Similarly, the magnetic flux that flows from the S-pole magnet magnetic pole Ms to the circumferential non-magnet magnetic pole part 25 side (side not adjacent to the magnet magnetic pole Mn) is moved to the outer peripheral surface 23b side of the rotor core 23 by the magnetic resistance of the slit part 26b. Be guided. Thereby, the area | region adjacent to the magnetic pole Ms of the S pole in the non-magnetic magnetic pole part 25 functions as a core magnetic pole Cn (pseudo magnetic pole) of the N pole by the magnet magnetic flux of the magnet magnetic pole Ms.

  In each non-magnet magnetic pole portion 25, the region between the pair of slit portions 26a and 26b (that is, between the core magnetic poles Cn and Cs) (inter-slit core portion 28) is caused by the magnetic resistance of the slit portions 26a and 26b. The magnetic poles Mn and Ms are configured to be hardly affected by the magnetic flux. That is, the inter-slit core portion 28 of each non-magnet magnetic pole portion 25 is configured such that no magnetic pole is formed by the magnet magnetic flux of the magnet magnetic poles Mn and Ms (permanent magnet 22).

  In the rotor 21 having the above-described configuration, the N-pole magnet magnetic pole Mn, the S-pole core magnetic pole Cs, the inter-slit core 28, the N-pole core magnetic pole Cn, and the S-pole magnet magnetic pole are sequentially arranged in the circumferential clockwise direction. Ms, N magnetic poles Mn,... Are repeated.

  Note that the opening angle θa (occupied angle) around the axis L of each inter-slit core portion 28 is substantially equal to the circumferential angle formed by the slit portions 26a and 26b described above, and is approximately 50 ° in the present embodiment. It has become. Further, the opening angle θc (occupied angle) about the axis L of each core magnetic pole Cn, Cs is the opening angle of each magnet magnetic pole Mn, Ms from the relationship that the inter-slit core portion 28 is formed in each non-magnet magnetic pole portion 25. It is configured to be smaller than the angle θm (45 ° in the present embodiment).

Next, the operation of this embodiment will be described.
A three-phase drive current (AC) having a phase difference of 120 ° is supplied from a drive circuit (not shown) to the U-phase windings U1 to U4, the V-phase windings V1 to V4, and the W-phase windings W1 to W4, respectively. And each winding U1-W4 is excited at the same timing for every phase, and a rotating magnetic field generate | occur | produces in the stator 11. FIG. Then, the rotor 21 is rotated by the interaction between the rotating magnetic field on the stator 11 side and the magnetic flux of the magnetic poles (magnet magnetic poles Mn, Ms and core magnetic poles Cn, Cs) on the rotor 21 side.

  When the rotor 21 rotates at high speed, field weakening control for supplying a field weakening current (d-axis current) to the winding 13 is executed. Here, the magnetic action by the field weakening control will be described with reference to FIGS. 2A and 2B, for convenience of explanation, only the U phase is illustrated as a configuration on the side of the stator 11, and illustration of the other phases is omitted.

  When the rotor 21 rotates at a high speed (field weakening control), the rotation position of the rotor 21 as shown in FIG. 2A, that is, the N-pole magnet magnetic pole Mn faces the U-phase windings U1 and U3 in the radial direction. In addition, a description will be given by taking as an example the rotational position of the rotor 21 in which the core portion 28 between the slits faces the U-phase windings U2 and U4 in the radial direction. At this time, in the U-phase windings U1 and U3, the magnetic flux (magnetic flux outward in the radial direction) generated by the opposing N-pole magnet magnetic pole Mn is the flux linkage caused by the field weakening current (linkage magnetic flux in the radial inner direction). ), And the interlinkage magnetic flux φx that passes outward in the radial direction is generated in the U-phase windings U1 and U3.

  On the other hand, in the U-phase windings U2 and U4, the opposed rotor 21 side portion is not a magnetic pole but an inter-slit core portion 28 that is not substantially affected by the magnet magnetic flux. For this reason, the d-axis magnetic flux generated by the supply of the field weakening current (d-axis current) passes through the inter-slit core portion 28 (rotor core 23) without being substantially affected by the magnet magnetic flux on the rotor 21 side. As a result, the interlinkage magnetic flux φy passing inward in the radial direction based on the field weakening current is generated in the U-phase windings U2 and U4 without being canceled by the magnetic pole on the rotor 21 side. That is, in the U-phase windings U2 and U4, an interlinkage magnetic flux φy having a phase opposite to the interlinkage magnetic flux φx generated in the U-phase windings U1 and U3 by the magnetic pole Mn is generated.

  At this time, an induced voltage due to the interlinkage magnetic fluxes φx and φy is generated in each U-phase winding U1 to U4. Since the interlinkage magnetic fluxes φx and φy are in opposite phases as described above, an induced voltage generated in the U-phase windings U2 and U4 by the interlinkage magnetic flux φy and generated in the U-phase windings U1 and U3 by the interlinkage magnetic flux φx. The induced voltage has opposite polarity (reverse phase). For this reason, the synthetic | combination induced voltage which synthesize | combined the induced voltage of each U-phase winding U1-U4 is reduced effectively.

  Note that the above effect also occurs when the S-pole magnet magnetic pole Ms faces the U-phase windings U1 and U3, for example. That is, when the S magnetic pole Ms faces the U-phase windings U1 and U3, the inter-slit core portion 28 faces the U-phase windings U2 and U4, respectively. The voltage and the induced voltage generated in the U-phase windings U2 and U4 are in opposite phases, and the combined induced voltage of each U-phase winding U1 to U4 is effectively reduced.

  In the above description, the combined induced voltage of the U-phase windings U1 to U4 has been described as an example. Similarly, in the V-phase windings V1 to V4 and the W-phase windings W1 to W4, the inter-slit core portion 28 is provided on the rotor core 23. The composite induced voltage is reduced due to the provision of.

  Next, when the rotor 21 is rotated at a high speed (at the time of field weakening control), when the rotor 21 is in a rotational position as shown in FIG. 2B, that is, the N-pole magnet magnetic pole Mn is placed in the U-phase windings U1, U3. And the magnetic action when the N-pole core magnetic pole Cn is opposed to the U-phase windings U2 and U4 in the radial direction.

  Even at this time, in the U-phase windings U1 and U3, the magnet magnetic flux (magnetic flux outward in the radial direction) generated by the opposing N-pole magnet magnetic pole Mn is weakened. Is generated in the U-phase windings U1 and U3 and passes outward in the radial direction.

  On the other hand, the core magnetic pole Cn facing the U-phase windings U2 and U4 is a pseudo magnetic pole having no magnet, and has a weaker magnetic force applied to the stator 11 side than the magnet magnetic pole Mn. Thereby, the interlinkage magnetic flux φy of the U-phase windings U2 and U4 facing the core magnetic pole Cn is smaller than the interlinkage magnetic flux φx of the U-phase windings U1 and U3 facing the magnet magnetic pole Mn. The induced voltage generated in windings U2 and U4 is smaller than the induced voltage generated in U-phase windings U1 and U3. Therefore, the combined induced voltage obtained by synthesizing the induced voltages generated in the U-phase windings U1 to U4 is reduced by a decrease in the induced voltage in the U-phase windings U2 and U4. Thus, when the N-pole magnet magnetic pole Mn faces the U-phase windings U1 and U3 in the radial direction, the portion on the rotor 21 side that faces the U-phase windings U2 and U4 in the radial direction is the N-pole core magnetic pole. Even in the case of Cn, the combined induced voltage of the U-phase windings U1 to U4 is reduced.

  In the above description, the decrease in the combined induction voltage when the U-phase windings U1 to U4 face the N pole of the rotor 21 has been described as an example. However, in the V-phase windings V1 to V4 and the W-phase windings W1 to W4, The same is true for the S pole of the rotor 21, and similarly, the combined induced voltage is reduced by the core portion 28 between the slits or the core magnetic pole Cs.

  Further, in the winding mode in which the windings 13 are connected in series in each phase as in the present embodiment, the sum of the induced voltages generated in the respective windings 13 for each phase becomes the combined induced voltage. The induced voltage tends to increase. Therefore, by providing the inter-slit core portion 28 and the core magnetic poles Cn and Cs as described above in the configuration in which the windings 13 are serially connected in each phase, the effect of suppressing the combined induced voltage can be obtained more remarkably. It is possible to achieve higher rotation of the motor 10.

  Further, the field weakening current supplied to the winding 13 can be kept small by the action of the core portion 28 between the slits or the core magnetic poles Cn and Cs. Since the field weakening current can be reduced, the permanent magnet 22 is difficult to demagnetize during field weakening control, and the copper loss of the winding 13 can be suppressed. In other words, the amount of interlinkage magnetic flux that can be reduced with the same amount of field-weakening current increases, so that higher rotation by field-weakening control can be obtained more effectively.

Next, characteristic effects of the present embodiment will be described.
(1) The winding 13 of the stator 11 includes four U-phase windings U1 to U4, V-phase windings V1 to V4, and W-phase windings W1 to W4, respectively, corresponding to the supplied three-phase driving current. Thus, the four windings of each phase are connected in series. That is, the winding 13 of the stator 11 includes at least two windings (first winding and second winding) connected in series in each phase.

  The rotor 21 has a U-phase winding U2 at a rotational position of the rotor 21 where the magnet magnetic pole Mn, Ms having the permanent magnet 22 and the magnet magnetic pole Mn (or the magnet magnetic pole Ms) face the U-phase windings U1, U3, for example. , U4 and the non-magnetic magnetic pole portion 25 of the rotor core 23. Then, the non-magnet magnetic pole portion 25 of the rotor core 23 is weakened by the core magnetic poles Cn and Cs that function as magnetic poles opposite to the magnetic poles Mn and Ms by the magnetic fluxes of the magnetic magnetic poles Mn and Ms, and the windings 13 facing each other. It comprises an inter-slit core portion 28 (magnetic flux allowing portion) that allows generation of field magnetic flux (linkage magnetic flux φy).

  According to this configuration, the core magnetic poles Cn and Cs are pseudo magnetic poles having no magnet, and the magnetic force applied to the stator 11 side is weaker than the magnet magnetic poles Mn and Ms. It can be kept small. Further, since the inter-slit core portion 28 allows generation of field-weakening magnetic flux (interlinkage magnetic flux φy) in the opposing winding 13, the interlinkage magnetic flux φy is generated in the winding 13 facing the inter-slit core portion 28. The induced voltage generated by the above is opposite in polarity to the induced voltage generated in the winding 13 facing the magnetic poles Mn and Ms. Thereby, the synthetic | combination induced voltage in the coil | winding 13 of each phase can be suppressed further smaller. Due to the action of the core magnetic poles Cn and Cs of the non-magnet magnetic pole part 25 and the core part 28 between the slits, the motor 10 can be rotated at a high speed.

  Here, considering a configuration in which all the non-magnet magnetic pole portions 25 of the rotor core 23 are the core magnetic poles Cn and Cs (a configuration in which each non-magnet magnetic pole portion 25 is provided with only one slit portion), although the torque can be increased, the core magnetic pole portions The magnetic force of Cn and Cs weakens and prevents the generation of field magnetic flux, which is disadvantageous for achieving high rotation. Therefore, by forming the inter-slit core portion 28 and the core magnetic poles Cn and Cs in the non-magnet magnetic pole portion 25 as in the present embodiment, it is possible to achieve high rotation while suppressing a decrease in torque as much as possible.

  In the present embodiment, the output characteristics (torque and rotation speed) of the motor 10 can be adjusted by changing the configuration of the pair of slit portions 26a and 26b formed in each non-magnet magnetic pole portion 25. Become.

  For example, the larger the angle formed by the pair of slit portions 26a and 26b in each non-magnet magnetic pole portion 25, the larger the opening angle θa of the inter-slit core portion 28 and the smaller the opening angle θc of the core magnetic poles Cn and Cs. As a result, the field weakening magnetic flux generated in the winding 13 at the time of field weakening control increases, which is advantageous for achieving high rotation. On the other hand, the smaller the angle formed by the pair of slit portions 26a, 26b in each non-magnet magnetic pole portion 25, the smaller the opening angle θa of the inter-slit core portion 28, and the larger the opening angle θc of the core magnetic poles Cn, Cs, This is an advantageous configuration for achieving high torque. Therefore, desired motor characteristics can be obtained by setting the angle between the slit portions 26a and 26b.

  (2) The inter-slit core portion 28 is provided between the N-pole core magnetic pole Cn and the S-pole core magnetic pole Cs in the circumferential direction of the rotor 21, and the N-pole and S-pole core magnetic poles Cn, Cs are respectively It is configured to be adjacent to the magnetic poles Mn and Ms of different polarities on the opposite side to the core portion 28 between the slits in the circumferential direction. According to this configuration, since the core magnetic poles Cn and Cs are respectively interposed between the core portion 28 between the slits and the magnet magnetic poles Mn and Ms in the circumferential direction, the core portion 28 between the slits is a magnetic flux of the magnet magnetic poles Mn and Ms. The configuration can be made less susceptible to influence. Accordingly, the inter-slit core portion 28 is more preferable because it allows the generation of field-weakening magnetic flux (linkage magnetic flux φy).

  (3) The opening angle θm of the facing surface of the magnet magnetic poles Mn and Ms facing the stator 11 (the outer peripheral surface of the magnetic poles Mn and Ms) is the facing surface of the core magnetic poles Cn and Cs facing the stator 11 (of the core magnetic poles Cn and Cs). It is set larger than the opening angle θc of the outer peripheral surface. As a result, the magnetic force of the magnet magnetic poles Mn and Ms and the magnetic force of the core magnetic poles Cn and Cs that function as pseudo magnetic poles can be secured by the magnetic flux of the magnet magnetic poles Mn and Ms, and the reduction in torque can be more suitably suppressed. .

  (4) Since the opening angle θa of the surface facing the stator 11 in the core portion 28 between slits (the outer peripheral surface of the core portion 28 between slits) is set larger than the opening angle θc of the outer peripheral surfaces of the core magnetic poles Cn and Cs. Thus, a configuration suitable for higher rotation can be obtained.

  (5) Since the rotor core 23 includes slit portions 26a and 26b as magnetoresistive portions between the core portion 28 between the slits adjacent to each other and the core magnetic poles Cn and Cs, the magnet magnetic pole Mn passing through the core magnetic poles Cn and Cs. It is possible to suppress the magnetic flux of Ms from flowing into the core portion 28 between the slits.

  In addition, the magnetoresistive portion can be easily configured in the rotor core 23 by using the slit portions 26 a and 26 b formed in the rotor core 23 as the magnetoresistive portion between the inter-slit core portion 28 and the core magnetic poles Cn and Cs. .

In addition, you may change the said embodiment as follows.
The configuration of the slit portions 26a and 26b in each non-magnet magnetic pole portion 25 is not limited to the above embodiment, and a magnetic flux allowing portion and a core magnetic pole Cn that allow each non-magnet magnetic pole portion 25 to generate a field weakening magnetic flux. , Cs can be appropriately changed to other configurations.

  For example, as shown in FIG. 3, it is good also as a structure which connected slit part 26a, 26b of the said embodiment by the inner peripheral side edge part. According to such a structure, it can suppress more suitably that the magnetic flux of the magnet magnetic poles Mn and Ms which pass the core magnetic poles Cn and Cs flows into the core part 28 between slits.

  Further, as shown in FIG. 4, for example, a plurality of bridge portions 31 may be formed at the radial intermediate portions of the slit portions 26a and 26b. Each bridge part 31 is formed in the rotor core 23, and is comprised so that between a pair of side surfaces which oppose the circumferential direction in each slit part 26a, 26b may be connected. In the configuration shown in the figure, the slit portions 26a and 26b are opened outward in the radial direction. According to such a configuration, the output characteristics (torque and rotational speed) of the motor 10 and the rigidity of the rotor core 23 can be easily adjusted by changing the configuration (number, axial direction, and radial dimension) of the bridge portion 31. It becomes possible.

  Further, for example, as shown in FIG. 5, an auxiliary magnet 32 may be provided in each of the slit portions 26a and 26b. In the figure, the magnetization directions of the permanent magnets 22 and the auxiliary magnets 32 are indicated by solid arrows, and the tip end side of the arrow indicates the N pole and the base end side of the arrow indicates the S pole. Each auxiliary magnet 32 is a permanent magnet having a rectangular parallelepiped shape, and has a magnetization direction corresponding to the core magnetic poles Cn and Cs adjacent in the circumferential direction. That is, the auxiliary magnet 32 provided in the slit part 26a is magnetized so that the core magnetic pole Cs side adjacent in the circumferential direction becomes the S pole. The auxiliary magnet 32 provided in the slit portion 26b is magnetized so that the side of the core magnetic pole Cn adjacent in the circumferential direction becomes an N pole. According to such a configuration, the amount of magnetic flux of the core magnetic poles Cn and Cs can be increased by the auxiliary magnets 32 in the slit portions 26a and 26b, and a decrease in torque can be more suitably suppressed.

  In the configuration shown in FIG. 5, the bridge portion 31 formed in each of the slit portions 26 a and 26 b is used for positioning the auxiliary magnet 32 in the radial direction. Further, the bridge portion 31 prevents the auxiliary magnet 32 from falling off from the slit portions 26a and 26b to the outside in the radial direction. Further, in the configuration shown in the figure, since the auxiliary magnet 32 is provided at a position closer to the inner peripheral side of each of the slit portions 26a and 26b, the magnetic flux of the auxiliary magnet 32 is changed to the outer peripheral side of the inter-slit core portion 28 (that is, It is difficult to flow in the field path of the field weakening magnetic flux. For this reason, it is possible to suppress the weak field magnetic flux from flowing through the core portion 28 between the slits due to the magnetic flux of the auxiliary magnet 32 (that is, hindering high rotation).

  Moreover, in the said embodiment, although each slit part 26a, 26b of the non-magnetic magnetic pole part 25 was formed along the radial direction of the rotor 21, it is not restricted to this, For example, as shown in FIG. It is good also as an aspect which 26b does not follow the radial direction of the rotor 21.

  In the configuration shown in the figure, the slit portions 26a and 26b are formed at a position on the outer peripheral side from the substantially center in the radial direction of the non-magnet magnetic pole portion 25, and the inner peripheral side ends of the slit portions 26a and 26b are non-magnets. The magnetic pole portions 25 are configured to approach each other at a substantially central position in the radial direction. And the core part 33 between slits of the outer peripheral side rather than each slit part 26a, 26b in the non-magnet magnetic pole part 25 functions as a magnetic flux permission part.

  Further, in the configuration shown in the figure, the auxiliary magnet 34 is embedded in the radially inner portion of the inter-slit core portion 33 (the slit portions 26a and 26b) in the non-magnet magnetic pole portion 25. The auxiliary magnet 34 is disposed on the circumferential center line L2 of the non-magnet magnetic pole portion 25. Further, the auxiliary magnet 34 has a rectangular shape that is long in the radial direction when viewed in the axial direction, the core magnetic pole Cn side in the circumferential direction (portion on the magnet magnetic pole Ms side of the slit 26b in the non-magnet magnetic pole portion 25) is the N pole, and the core Magnetization is performed so that the magnetic pole Cs side (the part on the magnet magnetic pole Mn side of the slit part 26a in the non-magnet magnetic pole part 25) becomes the S pole (see the solid line arrow in FIG. 6).

  According to such a configuration, the amount of magnetic flux of the core magnetic poles Cn and Cs can be increased by the auxiliary magnet 34, and a decrease in torque can be more suitably suppressed. Furthermore, in the same configuration, the auxiliary magnet 34 is provided radially inward of the slit portions 26a and 26b. For this reason, it is possible to suppress the magnetic flux of the auxiliary magnet 34 from entering the inter-slit core portion 33 by the slit portions 26a and 26b, and to prevent the magnetic flux of the auxiliary magnet 32 from hindering high rotation.

  Moreover, in the structure shown in FIG. 6, when aiming at the further torque improvement, as shown, for example in FIG. 7, you may provide the auxiliary magnet 32 in each slit part 26a, 26b. Even in such a configuration, in order to suppress interference with the magnetic path of the field weakening magnetic flux, it is preferable to provide the auxiliary magnet 32 at a position closer to the inner peripheral side of each slit portion 26a, 26b.

  In addition, it is preferable that the auxiliary magnets 32 and 34 in each said structure are comprised, for example with a neodymium magnet, a samarium cobalt (SmCo) magnet, a SmFeN type magnet, a ferrite magnet, an alnico magnet, etc. Further, the auxiliary magnets 32 and 34 may have any configuration of a sintered magnet and a bonded magnet.

  In the above embodiment, the slit portions 26a and 26b penetrate the rotor core 23 in the axial direction. However, the present invention is not limited thereto, and the slit portions 26a and 26b are holes that do not penetrate the rotor core 23 in the axial direction. The output characteristics (torque and rotational speed) of the motor 10 may be adjusted by changing the axial lengths of the portions 26a and 26b.

  In the rotor core 23 of the above embodiment, the slit portions 26a and 26b are formed as the magnetoresistive portions between the core portions 28 between the slits adjacent to each other and the core magnetic poles Cn and Cs. However, the present invention is not particularly limited thereto. . For example, the magnetoresistive portion between the core portion 28 between the slits and the core magnetic poles Cn and Cs may be configured by partially demagnetizing the rotor core 23 by laser irradiation.

  As shown in FIG. 8, the outer diameter D1 of the non-magnet magnetic pole portion 25 (that is, the outer diameter of each core magnetic pole Cn, Cs and the outer diameter of the core portion 28 between slits) is changed to the outer diameter of each magnet magnetic pole Mn, Ms. You may comprise larger than D2.

  According to such a configuration, the air gap (gap) between the stator-side teeth 12a and the inner peripheral surface of the stator side is smaller in the non-magnet magnetic pole portion 25 than in the magnet magnetic poles Mn and Ms. That is, since the inter-slit core portion 28 of the non-magnet magnetic pole portion 25 and the core magnetic poles Cn, Cs are closer to the inner peripheral surface of the tooth 12a, the field weakening magnetic flux is weakened to the inter-slit core portion 28 and the core magnetic poles Cn, Cs. Becomes easier to pass. Thereby, the synthetic induction voltage in each phase can be suppressed to a smaller value, which can contribute to further higher rotation.

  In the rotor 21 of the above embodiment, the magnetic flux allowing portion (the inter-slit core portion 28) configured in the non-magnet magnetic pole portion 25 is integrally formed with the rotor core 23. That is, the rotor core 23 is configured as an integral part including the magnetic flux allowance portion (core portion 28 between the slits). However, the present invention is not limited to this, and at least a part of the portion constituting the magnetic flux allowance portion may be configured separately. .

  For example, in the configuration shown in FIG. 9, the rotor core 23 includes a core body 51 having the same magnetic pole pair P and core magnetic poles Cn and Cs as in the above embodiment, and a separate core member 52 coupled to the core body 51. I have.

  The core main body 51 is formed in a substantially cylindrical shape from, for example, an iron material of a cold rolled steel plate (SPCC), and the rotating shaft 24 is fixed at the center. Further, the core body 51 has an accommodation recess 53 that is recessed in the non-magnet magnetic pole portion 25 of the rotor core 23 so as to be recessed radially inward from the outer peripheral surface of the core body 51. Both end surfaces in the circumferential direction of the housing recess 53 are formed in a planar shape along the radial direction, and connecting projections 54 projecting in the circumferential direction are formed in the housing recess 53 on both end surfaces. Each connection convex part 54 has comprised the taper shape which the width along the radial direction of the rotor 21 spreads to the protrusion front-end | tip (circumferential front-end | tip).

  In the core body 51, an N-pole core magnetic pole Cn is formed between the accommodation recess 53 and the circumferential direction of the S-pole magnet magnetic pole Ms, and an S-pole is provided between the accommodation recess 53 and the circumferential direction of the N-pole magnet magnetic pole Mn. A core magnetic pole Cs is configured. In addition, a magnetic resistance hole 55 penetrating the core body 51 in the axis L direction is formed in a radially inner portion of the housing recess 53 in the core body 51. The magnetoresistive hole 55 suppresses a short circuit of the magnetic flux between the magnet magnetic poles Mn and Ms configured with the non-magnet magnetic pole portion 25 sandwiched in the circumferential direction.

  A separate core member 52 having a fan shape with the axis L of the rotating shaft 24 as the center is accommodated in the accommodating recess 53 of the core body 51. The separate core member 52 is made of a material (for example, amorphous metal or permalloy) having a higher magnetic permeability than the core body 51 (for example, iron material). The outer peripheral surface of the separate core member 52 has an arc shape centered on the axis L when viewed from the direction of the axis L of the rotating shaft 24, and the outer peripheral surface of the separate core member 52 and the outer peripheral surface of the core body 51 are , And are located on the same circle centered on the axis L.

  Both end surfaces in the circumferential direction of the separate core member 52 have a planar shape along the radial direction and are opposed to both end surfaces in the circumferential direction of the housing recess 53. That is, the separate core member 52 is disposed between the N-pole core magnetic pole Cn and the S-pole core magnetic pole Cs in the circumferential direction. And the connection recessed part 61 with which the connection convex part 54 of the core main body 51 is fitted is formed in the circumferential direction both end surfaces of the separate core member 52, respectively. The separate core member 52 is fixed in the housing recess 53 by fitting the connection protrusions 54 to the connection recesses 61.

  In the fixed state of the separate core member 52, between the circumferential end surfaces of the separate core member 52 and the circumferential end surfaces of the receiving recess 53, and the radial inner side surface of the separate core member 52 and the diameter of the receiving recess 53 A gap K3 is provided between the inner side surface in the direction. Further, a gap K <b> 4 is provided between the respective connecting recesses 61 and the circumferential direction of each connecting protrusion 54 fitted in each connecting recess 61. That is, the separate core member 52 is in contact with the core body 51 side (the connecting convex portion 54) only on both side surfaces in the radial direction of the connecting concave portion 61.

  The separate core member 52 is configured to be line symmetric with respect to the circumferential center line L2 of the non-magnet magnetic pole portion 25. The opening angle (occupied angle) around the axis L of the separate core member 52 is set in the same manner as the opening angle θa of the inter-slit core portion 28 of the above embodiment. Further, in the configuration shown in the figure, the inner diameter of the separate core member 52 is about half of the outer diameter of the rotor core 23 (the outer diameter of the core body 51). You may set to more than half or less than half of the outer diameter of the rotor core 23.

  According to such a configuration, the separate core member 52 functions as a magnetic flux allowing portion that allows the generation of field-weakening magnetic fluxes, substantially like the inter-slit core portion 28 of the above embodiment. Rotation can be achieved. In the same configuration, the separate core member 52 is configured separately from the core body 51 having the magnet magnetic poles Mn and Ms and the core magnetic poles Cn and Cs. For this reason, interference between the magnetic path of the field weakening magnetic flux (d-axis magnetic path) in the separate core member 52 and the magnetic paths of the magnetic poles Mn and Ms in the core body 51 can be suppressed. As a result, the field-weakening magnetic flux can easily pass through the separate core member 52, thereby contributing to further higher rotation.

  Further, in the same configuration, the separate core member 52 is made of a material having a higher magnetic permeability than the core body 51, so that the weakened magnetic field flux can be more easily passed through the separate core member 52. As a result, it can contribute to further higher rotation. Further, in the constituent parts of the rotor core 23, at least the separate core member 52 is made of a material having high magnetic permeability, and the core body 51 is made of an inexpensive iron material or the like, so that an increase in manufacturing cost is suppressed and high rotation speed is increased. Can be achieved.

  Furthermore, since the core magnetic poles Cn and Cs are respectively interposed between the separate core member 52 and the magnet magnetic poles Mn and Ms in the circumferential direction, the separate core member 52 is more influenced by the magnetic fluxes of the magnet magnetic poles Mn and Ms. It can be configured to be difficult to receive. Further, since the gaps K3 are provided between the separate core member 52 and the core magnetic poles Cn and Cs in the circumferential direction, the interference of the magnetic poles Mn and Ms with the field weakening magnetic flux passing through the separate core member 52 is prevented. It can be further suppressed.

  In the configuration shown in FIG. 9 described above, the separate core member 52 is connected by the connecting convex portion 54 formed integrally with the core body 51. However, the present invention is not limited to this, for example, as shown in FIG. The core body 51 and the separate core member 52 may be connected via a connecting member 62 that is separate from the 51 and the separate core member 52.

  The connecting member 62 is provided across the separate core member 52 and the core body 51 on both sides in the circumferential direction of the separate core member 52, and both end portions in the circumferential direction of each connecting member 62 are provided in the separate core member 52. Are fitted into connecting recesses 63 and 64 formed on both end surfaces in the circumferential direction and on both end surfaces in the circumferential direction of the accommodating recess 53, respectively. The radial installation position of the connecting member 62 is set to the radial center position of the separate core member 52. In addition, each connecting member 62 has a tapered shape in which the radial width increases from the center in the circumferential direction to both ends in the circumferential direction. By this connecting member 62, the core main body 51 (accommodating recess 53) and the separate core member 52 are connected so as not to contact each other. The connecting member 62 is made of a material (for example, resin, stainless steel, brass, etc.) having a larger magnetic resistance than the core body 51 and the separate core member 52.

  According to such a configuration, the core body 51 and the separate core member 52 can be configured to be connected only by the connecting member 62. Then, by using a material having a larger magnetic resistance than the core body 51 and the separate core member 52 as the constituent material of the connection member 62, the magnetic fluxes of the magnetic poles Mn and Ms of the core body 51 are separated from the core through the connection member 62. It can suppress flowing to the member 52 side. As a result, the interference of the magnetic poles Mn and Ms with respect to the field weakening magnetic flux passing through the separate core member 52 can be further suppressed. In the configuration shown in FIG. 10, the gap K3 is provided between the housing recess 53 of the core body 51 and the separate core member 52. However, the present invention is not limited to this. For example, a filler such as a resin is provided in the gap K3. And the filler may function as a connecting member that connects the core body 51 and the separate core member 52.

  9 and 10, the separate core member 52 is preferably made of a material mainly having a magnetization easy axis (a crystal orientation easily magnetized) in the circumferential direction. According to this, the field-weakening magnetic flux can easily pass through the d-axis magnetic path in the separate core member 52, and as a result, it can contribute to further higher rotation.

  Further, in the configuration as shown in FIGS. 9 and 10, a cylindrical cover member that covers the outer peripheral surface of the rotor 21 may be provided. According to this, it is possible to suppress the separate core member 52 from dropping from the core body 51 by the cover member.

  In the above embodiment, the windings of the respective phases, that is, the U-phase windings U1 to U4, the V-phase windings V1 to V4, and the W-phase windings W1 to W4 are connected in series, respectively. However, the winding mode may be changed as appropriate. For example, when the U phase is taken as an example of modification, U phase windings U1 and U2 are connected in series, U phase windings U3 and U4 are connected in series, and a series pair of these U phase windings U1 and U2 is connected. And a series pair of U-phase windings U3 and U4 may be connected in parallel.

  In the above embodiment, the rotor 21 has 8 poles and the number of windings 13 of the stator 11 is 12 (that is, the motor configuration has 8 poles and 12 slots). The number of can be appropriately changed according to the configuration.

  In the above embodiment, the number of magnet magnetic poles Mn and the number of core magnetic poles Cn are the same (two in each case) in the N pole of the rotor 21, for example. For example, the number of magnet magnetic poles Mn may be three (or one) and the number of core magnetic poles Cn may be one (or three). The same change may be made on the S pole side (magnet magnetic pole Ms and core magnetic pole Cs) of the rotor.

  In the above embodiment, the core magnetic pole Cn and the core magnetic pole Cs are respectively provided in the N pole and the S pole of the rotor 21, but the present invention is not particularly limited thereto. May be provided, and the other pole may be composed entirely of magnet magnetic poles.

  In each of the magnetic poles Mn and Ms of the above-described embodiment, the pair of permanent magnets 22 embedded in the rotor core 23 are arranged in a substantially V shape that expands to the outer peripheral side when viewed in the axial direction. However, the configuration of the permanent magnets in the magnet magnetic poles Mn and Ms can be changed as appropriate. For example, it is good also as a structure which has one permanent magnet per one magnetic pole Mn and Ms.

  Further, the rotor 21 of the above embodiment has an embedded magnet type structure (IPM structure) in which the permanent magnets 22 constituting the magnetic poles Mn and Ms are embedded in the rotor core 23, but the magnetic poles Mn and Ms are formed. The surface magnet type structure (SPM structure) in which the permanent magnet to be fixed to the outer peripheral surface of the rotor core 23 may be used.

In the above embodiment, the permanent magnet 22 is a sintered magnet, but other than this, for example, a bonded magnet may be used.
In the above embodiment, the rotor core 23 has a laminated structure of the core sheets. However, for example, a green core or an integrated block formed by forging (cold forging) or cutting may be used.

  In the above embodiment, the rotor 21 is embodied as the inner rotor type motor 10 arranged on the inner peripheral side of the stator 11, but is not particularly limited to this, and the outer rotor type in which the rotor is arranged on the outer peripheral side of the stator It may be embodied in the motor.

  In the above-described embodiment, the radial gap type motor 10 in which the stator 11 and the rotor 21 are opposed to each other in the radial direction is embodied. You may apply to an axial gap type motor.

  -You may combine embodiment mentioned above and each modification suitably.

  DESCRIPTION OF SYMBOLS 10 ... Motor, 11 ... Stator, 12 ... Stator core, 12a ... Teeth, 13 ... Winding, 21 ... Rotor, 22 ... Permanent magnet, 23 ... Rotor core, 24 ... Rotating shaft, 25 ... Non-magnet magnetic pole part, 26a, 26b ... Slit part (magnetic resistance part), 28, 33 ... inter-slit core part (magnetic flux allowing part), 32, 34 ... auxiliary magnet, 51 ... core body, 52 ... separate core member, 62 ... connecting member, K3 ... gap, Mn, Ms: Magnet magnetic poles, Cn, Cs: Core magnetic poles, U1-U4: U-phase windings, V1-V4: V-phase windings, W1-W4: W-phase windings.

Claims (12)

A motor in which a rotor rotates in response to a rotating magnetic field generated by supplying a drive current to a winding of a stator,
The winding includes a first winding and a second winding that are excited at the same timing by the drive current and connected in series.
The rotor is
A magnetic pole having a permanent magnet;
A core magnetic pole made of a part of a rotor core, the magnetic pole of the magnet facing the second winding at a rotational position of the rotor facing the first winding;
A part of the rotor core, the magnetic pole facing the second winding at the rotational position of the rotor facing the first winding, and a chain caused by a field weakening current in the second winding A motor comprising: a magnetic flux allowing portion that allows generation of an alternating magnetic flux. The motor according to claim 1,
The magnet magnetic pole and the core magnetic pole are respectively provided on both the north and south poles of the rotor;
The magnetic flux allowing portion is provided between the core magnetic pole of N pole and the core magnetic pole of S pole in the circumferential direction of the rotor,
The N-pole and S-pole core magnetic poles are adjacent to the magnet poles having different polarities on the side opposite to the magnetic flux allowing portion in the circumferential direction. The motor according to claim 2,
An opening angle of a surface of the magnet magnetic pole facing the stator is set to be larger than an opening angle of the core magnetic pole facing the stator. The motor according to claim 2 or 3,
An opening angle of a surface facing the stator in the magnetic flux allowing portion is set larger than an opening angle of a facing surface of the core magnetic pole facing the stator. The motor according to any one of claims 2 to 4,
The rotor core includes a magnetoresistive portion between the magnetic flux allowing portion and the core magnetic pole adjacent to each other. The motor according to claim 5, wherein
The motor according to claim 1, wherein the magnetoresistive portion is a slit portion provided in the rotor core. The motor according to claim 6, wherein
An auxiliary magnet is provided in the slit portion. The motor according to any one of claims 2 to 7,
The motor according to claim 1, wherein an auxiliary magnet for flowing a magnetic flux to the core magnetic pole is embedded in a portion radially inward of the magnetic flux allowing portion in the rotor core. The motor according to any one of claims 1 to 8,
The rotor core includes a core body having the magnet magnetic pole and the core magnetic pole, and a separate core member that is a separate component connected to the core body and forms at least a part of the magnetic flux allowing portion. A motor characterized by that. The motor according to claim 9, wherein
The separate core member is made of a material having a higher magnetic permeability than the core body. The motor according to claim 9 or 10,
The magnet magnetic pole and the core magnetic pole of the core body are respectively provided on both the N pole and the S pole of the rotor,
The separate core member constituting the magnetic flux allowing portion is provided between the core magnetic pole of N pole and the core magnetic pole of S pole in the circumferential direction of the rotor,
Each of the core poles of N pole and S pole is configured to be adjacent to the magnet pole of a different polarity on the opposite side of the separate core member in the circumferential direction,
An air gap is provided between the separate core member in the circumferential direction and the core magnetic poles of N and S poles, respectively. The motor according to any one of claims 9 to 11,
The motor, wherein the core main body and the separate core member are connected to each other via a connection member made of a material having a larger magnetic resistance than the core main body and the separate core member.

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