JP6672914B2 - motor - Google Patents

Description

  The present invention relates to a motor.

  Conventionally, a permanent magnet motor such as a brushless motor includes, as shown in Patent Document 1, 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, The rotor rotates by receiving a rotating magnetic field generated by supplying a driving current to the winding of the stator.

JP 2014-135852 A

  In the above-described permanent magnet motor, as the rotor rotates at a higher speed, the induced voltage generated in the stator winding due to the increase of the linkage flux by the permanent magnet of the rotor increases, and this induced voltage lowers the motor output. This hinders the motor from rotating at a high speed. Therefore, by reducing the magnetic force of the rotor magnetic poles, for example, by reducing the size of the permanent magnet of the rotor, it is possible to suppress the induced voltage at the time of high rotation of the rotor, but the resulting torque also decreases. Therefore, there is still room for improvement in this respect.

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

A motor that solves the above problem is a motor in which a rotor rotates by receiving a rotating magnetic field generated by supplying a drive current to a winding of a stator, and the windings are driven 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 magnet pole having a permanent magnet and a part of a rotor core, and the magnet pole is the first pole. A core magnetic pole facing the second winding at a rotational position of the rotor facing the winding of the rotor, and a part of the rotor core, wherein the magnetic pole is not formed by the magnet magnetic flux of the magnet magnetic pole; when the magnetic pole is opposed to the second winding at a rotational position of the rotor which faces the first winding, the magnetic flux allowed to permit the occurrence of flux linkage ascribable to the field weakening current in the second winding Section.

  According to this configuration, in the rotation 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 permitting portion) other than the magnet magnetic pole in the rotor core is connected to the second winding. It is constituted so that it may face. This makes it possible to reduce the combined induced voltage obtained by combining the induced voltages generated in the first and second windings, and as a result, it is possible to increase the rotation speed of the motor.

  Here, considering a configuration in which the non-magnet magnetic pole portion of the rotor core is entirely a core magnetic pole, although torque can be gained, the magnetic force of the core magnetic pole prevents generation of linkage flux (field weakening magnetic flux) due to weakening field current. This is disadvantageous for increasing the rotation speed. Therefore, in the present configuration, not all of the non-magnetic magnetic pole portions of the rotor core are core magnetic poles, but the non-magnetic magnetic pole portions include both a magnetic flux permitting portion that allows generation of a field weakening magnetic flux and a core magnetic pole. Thus, it is possible to achieve a high rotation speed while suppressing a 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 is the combined induced voltage. , The synthetic induced voltage tends to increase. For this reason, by employing the above-described rotor configuration in a configuration in which the first and second windings are connected in series, the effect of suppressing the combined induced voltage can be more remarkably obtained, and the rotation speed of the motor can be increased. Is more suitable.

  In the above-mentioned motor, the magnet magnetic pole and the core magnetic pole are respectively provided on both the N pole and the S pole of the rotor, and the magnetic flux permitting unit is configured to have the N magnetic pole and the S pole in the circumferential direction of the rotor. It is preferable that the N-pole and S-pole core magnetic poles provided between the core magnetic poles are adjacent to the different magnetic poles on the side opposite to the magnetic flux permitting portion in the circumferential direction.

  According to this configuration, the core magnetic pole is interposed between the magnetic flux permitting portion and the magnet magnetic pole in the circumferential direction, so that the magnetic flux permitting portion can be less affected by the magnetic flux of the magnet magnetic pole. This provides a more suitable configuration in which the magnetic flux permitting portion allows the generation of the field weakening magnetic flux.

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

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

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

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

  According to this configuration, since the rotor core includes the magnetic resistance portion between the magnetic flux permitting portion and the core magnetic pole adjacent to each other, it is possible to suppress the magnetic flux of the magnet magnetic pole passing through the core magnetic pole from flowing to the magnetic flux permitting portion.

In the above motor, it is preferable that the magnetic resistance portion is a slit provided in the rotor core.
According to this configuration, since the magnetic resistance portion is the slit portion, the magnetic resistance portion can be easily formed on the rotor core.

In the above motor, it is preferable that an auxiliary magnet is provided in the slit.
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 decrease in torque can be suppressed more appropriately.

In the motor described above, it is preferable that an auxiliary magnet that allows a magnetic flux to flow through the core magnetic pole be buried in a portion of the rotor core radially inside the magnetic flux permitting portion.
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 permitting portion, and a decrease in torque can be more suitably suppressed.

  In the above motor, 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 permitting portion. It is preferable to have.

  According to this configuration, the core body having the magnet magnetic pole and the core magnetic pole and the separate core member that forms at least a part of the magnetic flux permitting portion are formed separately from each other. Interference between the magnetic path of the magnetic flux and the magnetic path of the magnetic flux of the magnetic pole in the core body can be suppressed. This facilitates passage of the field weakening magnetic flux through the separate core member (magnetic flux permitting portion), thereby contributing to a further higher rotation of the motor.

In the above motor, it is preferable that the separate core member is made of a material having a higher magnetic permeability than the core body.
According to this configuration, the weak magnetic field can be more easily passed through the separate core member (magnetic flux permitting portion), and as a result, it is possible to contribute to a further higher rotation of the motor. Further, in the components of the rotor core, at least the separate core member is made of a material having high magnetic permeability, and the core body is made of an inexpensive material, whereby high rotation can be achieved 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 on both an N pole and an S pole of the rotor, respectively, and the separate core member that constitutes the magnetic flux permitting part is provided by the rotor of the rotor. In the circumferential direction, provided between the N-pole core magnetic pole and the S-pole core magnetic pole, and the N-pole and S-pole core magnetic poles are different on the opposite side from the separate core member in the circumferential direction. It is preferable that a gap is provided between the separate core member and the N-pole and S-pole core poles in the circumferential direction.

  According to this configuration, since the core magnetic pole is interposed in the circumferential direction between the separate core member and the magnetic pole that constitute the magnetic flux permitting portion, the separate core member is less likely to be affected by the magnetic flux of the magnetic pole. can do. That is, the interference of the magnetic flux of the magnet pole with the field weakening magnetic flux passing through the separate core member can be further suppressed. Further, since a gap is provided between the separate core member and the N-pole and S-pole core poles in the circumferential direction, the interference of the magnetic flux of the magnet 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 higher 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 higher 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 suppressed 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.

  ADVANTAGE OF THE INVENTION According to the motor of this invention, high rotation can be achieved, suppressing the fall of a torque.

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

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 has a configuration in which a rotor 21 is disposed 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 each of the teeth 12a is wound 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 supplied three-phase driving currents (U-phase, V-phase, and W-phase), and U1, V1,. W1, U2, V2, W2, U3, V3, W3, U4, V4, W4.

  Looking at 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 regular intervals in the circumferential direction (90 ° intervals). Similarly, W-phase windings W1 to W4 are arranged at equal intervals in the circumferential direction (90 ° intervals).

  The windings 13 are 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.

[Rotor configuration]
As shown in FIG. 1B, the rotor 21 has an embedded magnet type structure (IPM structure) in which a permanent magnet 22 forming a magnetic pole is embedded in a rotor core 23. The rotor core 23 is formed in a cylindrical shape by stacking a plurality of core sheets made of a circular plate-shaped magnetic metal in the axial direction, and a rotation shaft 24 is inserted and fixed to 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 23b of the rotor core 23. More specifically, the rotor 21 includes a pair of an N-pole magnet magnetic pole Mn, an S-pole magnet magnetic pole Ms, an N-pole core magnetic pole Cn, and an S-pole core magnetic pole Cs. Each magnet magnetic pole Mn, Ms is a magnetic pole using the permanent magnet 22, and each core magnetic pole Cn, Cs is a magnetic pole using a part of the rotor core 23.

  Each of the magnetic poles Mn and Ms of the north pole and the south pole has a pair of permanent magnets 22 embedded in the rotor core 23, respectively. In each of the magnet poles Mn and Ms, the pair of permanent magnets 22 are arranged in a substantially V-shape that expands toward the outer periphery when viewed in the axial direction, and the magnetic pole center line in the circumferential direction (the straight line L1 in FIG. (See FIG. 2). Each of the permanent magnets 22 has a rectangular parallelepiped shape. Further, the pair of permanent magnets 22 in each of the magnetic poles Mn and Ms equally divides the rotor 21 in the circumferential direction by the number of poles (the total number of the magnetic poles Mn and Ms and the core magnetic poles Cn and Cs, and 8 in this embodiment). Are arranged so as to be within the angle range (in the present embodiment, the range of 45 °). Each of the permanent magnets 22 is, for example, an anisotropic sintered magnet and includes, for example, a neodymium magnet, a samarium cobalt (SmCo) magnet, an SmFeN-based magnet, a ferrite magnet, an alnico magnet, and 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 leading end of the arrow is the N pole and the base end of the arrow is the S pole. Is represented. As shown by the arrows, each of the permanent magnets 22 in the N-pole magnet magnetic pole Mn has an N pole on a surface facing each other (a surface on the magnetic pole center line side) in order to make the outer peripheral side of the magnetic pole Mn an N pole. It is magnetized so that the poles appear. Further, each permanent magnet 22 in the S-pole magnet magnetic pole Ms is magnetized so that the S-pole appears on the surface facing each other (the surface on the magnetic pole center line side) 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 interval between their circumferential center positions (magnetic pole centers) is 45 °. A pair of the magnet magnetic pole Mn and the S magnetic pole Ms is defined as a magnet magnetic pole pair P. Further, in the rotor 21 of the present embodiment, two magnet magnetic pole pairs P are provided at positions facing each other by 180 ° in the circumferential direction. More specifically, the N-pole magnet pole Mn of one magnet pole pair P and the N-pole magnet pole Mn of the other magnet pole pair P are arranged at 180 ° facing each other. The S-pole magnet magnetic pole Ms of the pair P and the S-pole magnet magnetic pole Ms of the other magnet pole pair P are arranged at positions facing each other by 180 °. That is, the magnet poles Mn and Ms (the permanent magnets 22) are provided to be point-symmetric about the axis L of the rotor 21 (the axis of the rotating shaft 24).

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

  Here, in the circumferential direction of the rotor core 23, the occupied angle of the pair of magnet magnetic poles P is substantially 180 °, and the remaining range is a portion where the magnet is not disposed (the 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 formed at approximately 90 ° intervals in the circumferential direction.

  Each non-magnet magnetic pole part 25 is provided with a pair of slit parts 26a and 26b as a magnetic resistance part. In the present embodiment, each slit portion 26a, 26b extends from a position near the fixing hole 23a of the rotor core 23 to a position near the outer peripheral surface 23b of the rotor core 23 along the radial direction. The slits 26a and 26b are holes that penetrate the rotor core 23 in the axial direction.

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

  In the rotor core 23, a magnetic resistance hole 27 is formed at a position on the inner peripheral side of the pair of permanent magnets 22 in each of the magnetic poles Mn and Ms. Each of the magnetic resistance holes 27 is a rectangular hole that is long in the radial direction when viewed in the axial direction, and is provided at a circumferential center position of each of the magnetic poles Mn and Ms. That is, in the present embodiment, the center between the magnetic resistance holes 27 of the magnet magnetic poles Mn and Ms adjacent in the circumferential direction is set to 45 °. Further, each of the magnetoresistive holes 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 of the air gaps K1 and K2 is a part of each magnet accommodating hole 23c formed in the rotor core 23 and accommodating each of the permanent magnets 22, and the inner peripheral side surface of each permanent magnet 22 faces each of the air gaps K1, The inner peripheral 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 housing hole 23c, and a gap K2 is provided between the permanent magnet 22 and the radially outer end of the magnet housing hole 23c. I have.

  The magnetic resistance holes 27 suppress short-circuiting of magnetic flux between the magnetic poles Mn and Ms in each magnetic pole pair P, and the air gaps K1 and K2 suppress short-circuiting of magnetic flux in each of the permanent magnets 22. Is done. With these, the magnetic flux (magnet magnetic flux) of the permanent magnet 22 of each magnet magnetic pole Mn, Ms is efficiently guided to the outer peripheral side of the magnet magnetic poles Mn, Ms and the non-magnetic magnetic pole part 25 side in the circumferential direction. Has become.

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

  More specifically, the magnet magnetic flux flowing from the N-pole magnet magnetic pole Mn to the non-magnet magnetic pole portion 25 side (the side not adjacent to the magnet magnetic pole Ms) in the circumferential direction is directed to the outer peripheral surface 23b side of the rotor core 23 by the magnetic resistance of the slit portion 26a. Be guided. Thus, a 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 magnetic flux of the magnet magnetic pole Mn.

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

  In each of the non-magnet magnetic pole portions 25, a 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 formed by the magnetic resistance of the slit portions 26a and 26b. The magnetic poles Mn and Ms are configured to be substantially unaffected by the magnetic flux of the magnets. In other words, 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 magnetic magnetic poles Mn and Ms (permanent magnets 22).

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

  The open angle θa (occupied angle) of each inter-slit core portion 28 about the axis L is substantially equal to the circumferential angle formed by the slit portions 26a and 26b, and is approximately 50 ° in the present embodiment. Has become. The opening angle θc (occupied angle) of the core magnetic poles Cn, Cs about the axis L is determined by the opening angle θc (occupation angle) of each magnet magnetic pole Mn, Ms because of the relationship between the non-magnet magnetic pole parts 25 and the inter-slit core part 28. It is configured to be smaller than the angle θm (45 ° in the present embodiment).

Next, the operation of the present 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. Then, the windings U1 to W4 are excited at the same timing for each phase, and a rotating magnetic field is generated in the stator 11. 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 and Ms and the core magnetic poles Cn and Cs) on the rotor 21 side.

  When the rotor 21 rotates at a 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. 2 (a) and 2 (b), for convenience of explanation, only the U-phase is illustrated as the configuration on the stator 11 side, and the other phases are not illustrated.

  When the rotor 21 rotates at high speed (during field weakening control), the rotational position of the rotor 21 as shown in FIG. 2A, that is, the N-pole magnet magnetic pole Mn radially opposes the U-phase windings U1 and U3. In addition, a description will be given of an example of the rotational position of the rotor 21 in which the inter-slit core portion 28 faces the U-phase windings U2 and U4 in the radial direction. At this time, in the U-phase windings U1 and U3, the magnet magnetic flux (radially outward magnetic flux) generated by the opposed N-pole magnet magnetic pole Mn is weakened by the linkage magnetic flux (radially inward linkage magnetic flux) due to the field current. ), A flux linkage φx that passes radially outward is generated in the U-phase windings U1 and U3.

  On the other hand, in the U-phase windings U2 and U4, the opposing portions on the rotor 21 side are not the magnetic poles but the inter-slit core portions 28 which are not substantially affected by the 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 (the rotor core 23) almost without being affected by the magnet magnetic flux on the rotor 21 side. As a result, in the U-phase windings U2 and U4, the linkage flux φy passing inward in the radial direction based on the field weakening current is generated without being canceled by the magnetic poles on the rotor 21 side. That is, in the U-phase windings U2 and U4, a linkage magnetic flux φy having a phase opposite to that of the linkage magnetic flux φx generated in the U-phase windings U1 and U3 by the magnet pole Mn is generated.

  At this time, an induced voltage is generated in each of the U-phase windings U1 to U4 by the linkage magnetic fluxes φx and φy. Since the interlinkage magnetic fluxes φx and φy have opposite phases as described above, the induced voltage generated in the U-phase windings U2 and U4 by the interlinkage magnetic flux φy and the U-phase windings U1 and U3 generated by the interlinkage magnetic flux φx. The induced voltages have opposite polarities (opposite phases). For this reason, the combined induced voltage obtained by combining the induced voltages of the U-phase windings U1 to U4 is effectively reduced.

  Note that the above-described action also occurs when the S-pole magnet magnetic pole Ms faces, for example, the U-phase windings U1 and U3. That is, when the S-pole magnet 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 have opposite phases, and the combined induced voltage of each of the U-phase windings 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. However, in the V-phase windings V1 to V4 and the W-phase windings W1 to W4, similarly, the inter-slit core portions 28 Causes a reduction in the combined induced voltage.

  Next, during high-speed rotation of the rotor 21 (during field-weakening control), when the rotor 21 is in a rotational position as shown in FIG. 2B, that is, when the N-pole magnet magnetic pole Mn is in the U-phase windings U1 and U3. The magnetic effect when the core magnetic pole Cn of the N pole is radially opposed to the U-phase windings U2 and U4 will be described.

  Also in this case, in the U-phase windings U1 and U3, the magnet magnetic flux (radially outward magnetic flux) generated by the opposed N-pole magnet magnetic pole Mn is weakened by the linkage magnetic flux (radially inward radially) due to the field current. (Interval magnetic flux), and a linkage magnetic flux φx passing radially outward is generated in the U-phase windings U1 and U3.

  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 smaller magnetic force applied to the stator 11 side than the magnet magnetic pole Mn. As a result, the interlinkage magnetic flux φy of the U-phase windings U2 and U4 opposed to the core magnetic pole Cn is smaller than the interlinkage magnetic flux φx of the U-phase windings U1 and U3 opposed to the magnet magnetic pole Mn. The induced voltage generated in the windings U2 and U4 becomes smaller than the induced voltage generated in the U-phase windings U1 and U3. Therefore, the combined induced voltage obtained by combining the induced voltages generated in the respective U-phase windings U1 to U4 is reduced by the reduced amount of the induced voltage in the U-phase windings U2 and U4. As described above, when the N-pole magnet magnetic pole Mn faces the U-phase windings U1 and U3 in the radial direction, the portion of the rotor 21 side radially facing the U-phase windings U2 and U4 is the N-pole core magnetic pole. Even when Cn, the combined induced voltage of each of the U-phase windings U1 to U4 is reduced.

  In the above description, the reduction of the combined induced voltage when the U-phase windings U1 to U4 face the N-pole of the rotor 21 has been described as an example, but in the V-phase windings V1 to V4 and the W-phase windings W1 to W4. The same applies to the S-pole of the rotor 21, and similarly, the combined induced voltage due to the interslit core portion 28 or the core magnetic pole Cs decreases.

  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 windings 13 for each phase is a 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 a configuration in which the windings 13 are connected in series in each phase, the effect of suppressing the combined induced voltage can be more remarkably obtained. This is more suitable for increasing the rotation speed of the motor 10.

  Further, the action of the inter-slit core portion 28 or the core magnetic poles Cn and Cs makes it possible to reduce the field weakening current supplied to the winding 13. Since the field weakening current can be reduced, the permanent magnet 22 is hardly demagnetized during the 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 by the same amount of field weakening current increases, so that a higher rotation speed by field weakening control can be more effectively obtained.

Next, the characteristic effects of the present embodiment will be described.
(1) The windings 13 of the stator 11 are formed from four U-phase windings U1 to U4, V-phase windings V1 to V4, and W-phase windings W1 to W4 in accordance with the supplied three-phase driving currents. 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.

  Further, the rotor 21 has a magnet magnetic pole Mn, Ms having a permanent magnet 22 and a U-phase winding U2 at a rotational position of the rotor 21 where the magnet magnetic pole Mn (or the magnet magnetic pole Ms) faces, for example, the U-phase windings U1, U3. , U4 and the non-magnetic magnetic pole portion 25 of the rotor core 23 facing the same. The non-magnet magnetic pole portion 25 of the rotor core 23 is weakened by the magnetic fluxes of the magnetic magnetic poles Mn and Ms, and the core magnetic poles Cn and Cs functioning as magnetic poles opposite to the magnetic magnetic poles Mn and Ms, and the windings 13 facing each other. And a slit-to-slit core portion 28 (magnetic flux permitting portion) that permits generation of a 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 is smaller than the magnet magnetic poles Mn and Ms. It can be kept small. In addition, the inter-slit core portion 28 allows the generation of a field-weakening magnetic flux (linkage magnetic flux φy) in the facing winding 13, and thus the interlinkage magnetic flux φy in the winding 13 facing the inter-slit core portion 28. The induced voltage generated by the winding 13 has a polarity opposite to that of the induced voltage generated in the winding 13 facing the magnetic poles Mn and Ms. This makes it possible to further reduce the combined induced voltage in the windings 13 of each phase. The rotation of the motor 10 can be increased by the action of the core magnetic poles Cn and Cs of the non-magnet magnetic pole portion 25 and the core portion 28 between the slits.

  Here, considering a configuration in which all the non-magnetic magnetic pole portions 25 of the rotor core 23 are the core magnetic poles Cn and Cs (a configuration in which each of the non-magnetic magnetic pole portions 25 is provided with only one slit portion), although the torque can be obtained, the core magnetic pole can be obtained. The magnetic force of Cn and Cs weakens and hinders 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 increase the rotation speed 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 slits 26 a and 26 b formed in each non-magnet magnetic pole 25. Become.

  For example, as the angle formed by the pair of slits 26a, 26b in each non-magnet magnetic pole part 25 increases, the opening angle θa of the interslit core part 28 increases, and the opening angle θc of the core magnetic poles Cn, Cs decreases. As a result, the field-weakening magnetic flux generated in the winding 13 during the field-weakening control is increased, which is advantageous in achieving high rotation. On the other hand, as the angle formed by the pair of slit portions 26a and 26b in each non-magnet magnetic pole portion 25 is smaller, the opening angle θa of the interslit core portion 28 is smaller, and the opening angle θc of the core magnetic poles Cn and Cs is larger. 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 side opposite to the circumferential inter-slit core portion 28. According to this configuration, since the core magnetic poles Cn and Cs are respectively interposed between the inter-slit core portion 28 and the magnet magnetic poles Mn and Ms in the circumferential direction, the inter-slit core portion 28 generates the magnetic flux of the magnet magnetic poles Mn and Ms. It is possible to make the configuration less susceptible to the influence. Accordingly, the inter-slit core portion 28 has a more preferable configuration in which the generation of the field weakening magnetic flux (linkage magnetic flux φy) is allowed.

  (3) The opening angle θm of the surface of the magnet poles Mn and Ms facing the stator 11 (the outer peripheral surface of the magnet poles Mn and Ms) is the surface of the core poles Cn and Cs facing the stator 11 (of the core poles Cn and Cs). The opening angle θc of the outer peripheral surface is set to be larger. Thereby, the magnetic force of the magnet magnetic poles Mn and Ms and the magnetic force of the core magnetic poles Cn and Cs functioning as pseudo magnetic poles can be secured by the magnetic fluxes of the magnetic magnetic poles Mn and Ms, and the decrease in torque can be suppressed more appropriately. .

  (4) The open angle θa of the surface of the inter-slit core portion 28 facing the stator 11 (the outer peripheral surface of the inter-slit core portion 28) is set to be larger than the open angle θc of the outer peripheral surfaces of the core magnetic poles Cn and Cs. It is possible to make the configuration more suitable for high rotation.

  (5) Since the rotor core 23 is provided with the slit portions 26a and 26b as the magnetic resistance portions between the inter-slit core portions 28 and the core magnetic poles Cn and Cs adjacent to each other, the magnet magnetic poles Mn and Cn passing through the core magnetic poles Cn and Cs are provided. It is possible to suppress the magnetic flux of Ms from flowing into the interslit core portion 28.

  Further, the magnetic resistance portion between the slit-to-slit core portion 28 and the core magnetic poles Cn, Cs is formed by the slit portions 26a and 26b formed in the rotor core 23, so that the magnetic resistance portion can be easily formed on the rotor core 23. .

The above embodiment may be modified 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-described embodiment. , Cs can be appropriately changed to other configurations.

  For example, as shown in FIG. 3, the slits 26a and 26b of the above embodiment may be connected to each other at an inner peripheral end. According to such a configuration, it is possible to more suitably suppress the magnetic flux of the magnet magnetic poles Mn and Ms passing through the core magnetic poles Cn and Cs from flowing to the interslit core portion 28.

  Further, for example, as shown in FIG. 4, a plurality of bridge portions 31 may be formed at radially intermediate portions of the respective slit portions 26a and 26b. Each bridge portion 31 is formed on the rotor core 23 and is configured to connect between a pair of circumferentially opposed side surfaces of the slit portions 26a and 26b. In the configuration shown in the figure, the slits 26a and 26b are open radially outward. According to such a configuration, the output characteristics (torque and rotation speed) of the motor 10 and the stiffness of the rotor core 23 are easily adjusted by changing the configuration (number and dimensions in the axial and radial directions) of the bridge portion 31. It becomes possible.

  Further, as shown in FIG. 5, for example, 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 leading end of the arrow indicates the N pole and the base end of the arrow indicates the S pole. Each auxiliary magnet 32 is a rectangular parallelepiped permanent magnet, 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 portion 26a is magnetized such that the core magnetic pole Cs adjacent in the circumferential direction becomes the S pole. The auxiliary magnet 32 provided in the slit portion 26b is magnetized so that 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 magnet 32 in each of 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 26a and 26b is used for positioning the auxiliary magnet 32 in the radial direction. In addition, the bridge portion 31 prevents the auxiliary magnet 32 from dropping radially outward from the slit portions 26a and 26b. In addition, 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 slits 26a and 26b, the magnetic flux of the auxiliary magnet 32 is transmitted to the outer peripheral side of the inter-slit core 28 (that is, It is difficult for the field flux to flow to the magnetic path side). Therefore, it is possible to suppress the field flux weakened from flowing to the inter-slit core portion 28 by the magnetic flux of the auxiliary magnet 32 (that is, to prevent the rotation speed from increasing).

  Further, in the above embodiment, the slits 26a and 26b of the non-magnet magnetic pole part 25 are formed along the radial direction of the rotor 21. However, the present invention is not limited to this. For example, as shown in FIG. 26b may not be along the radial direction of the rotor 21.

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

  Further, in the configuration shown in the figure, the auxiliary magnet 34 is embedded in a portion of the non-magnet magnetic pole portion 25 radially inside the inter-slit core portion 33 (each of the slit portions 26a and 26b). The auxiliary magnet 34 is disposed on the circumferential center line L2 of the non-magnet magnetic pole portion 25. The auxiliary magnet 34 has a rectangular shape that is long in the radial direction when viewed in the axial direction, and the core pole Cn side in the circumferential direction (the part of the non-magnet pole part 25 closer to the magnet pole Ms than the slit 26b) has an N pole, The magnetic pole Cs side (the portion of the non-magnet magnetic pole portion 25 closer to the magnet magnetic pole Mn than the slit portion 26a) is magnetized so as to be an 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 suppressed more appropriately. Further, in the same configuration, the auxiliary magnet 34 is provided radially inward of each of the slit portions 26a and 26b. For this reason, the magnetic flux of the auxiliary magnet 34 is suppressed from entering the inter-slit core 33 by the slits 26a and 26b, and the magnetic flux of the auxiliary magnet 32 can be prevented from hindering the high rotation.

  In the configuration shown in FIG. 6, when the torque is to be further increased, for example, as shown in FIG. 7, an auxiliary magnet 32 may be provided in each of the slits 26a and 26b. Even in such a configuration, it is preferable to provide the auxiliary magnet 32 at a position closer to the inner peripheral side of each of the slit portions 26a and 26b in order to suppress interference of the field weakening magnetic flux with the magnetic path.

  In addition, it is preferable that the auxiliary magnets 32 and 34 in each of the above-described configurations include, for example, a neodymium magnet, a samarium cobalt (SmCo) magnet, an SmFeN-based magnet, a ferrite magnet, an alnico magnet, and the like. In addition, the auxiliary magnets 32 and 34 may have any configuration of a sintered magnet and a bonded magnet.

  In the above embodiment, the slits 26a and 26b penetrate the rotor core 23 in the axial direction. However, the present invention is not limited to this. The slits 26a and 26b are holes that do not penetrate the rotor core 23 in the axial direction. The output characteristics (torque and rotation 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 magnetic resistance portions between the inter-slit core portions 28 and the core magnetic poles Cn and Cs adjacent to each other, but the present invention is not particularly limited thereto. . For example, a magnetic resistance portion between the slit-to-slit core portion 28 and the core magnetic poles Cn and Cs may be formed 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 part 25 (that is, the outer diameter of each core magnetic pole Cn, Cs and the outer diameter of the inter-slit core part 28) is changed to the outer diameter of each magnet magnetic pole Mn, Ms. It may be configured to be larger than D2.

  According to such a configuration, the air gap (gap) between the inner peripheral surface of the teeth 12a on 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 respective core magnetic poles Cn, Cs are closer to the inner peripheral surface of the tooth 12a, the field magnetic flux weakened to the inter-slit core portion 28 and the respective core magnetic poles Cn, Cs. Is easier to pass. As a result, the combined induced voltage in each phase can be further reduced, which can contribute to a further higher rotation.

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

  For example, in the configuration illustrated in FIG. 9, the rotor core 23 includes a core main body 51 having the same magnetic pole pairs P and core magnetic poles Cn and Cs as in the above embodiment, and a separate core member 52 connected to the core main body 51. Have.

  The core body 51 is formed in a substantially cylindrical shape from, for example, an iron material such as a cold-rolled steel plate (SPCC), and the rotating shaft 24 is fixed to a central portion. Further, the core body 51 has an accommodation recess 53 formed 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 flat along the radial direction, and connection protrusions 54 projecting in the circumferential direction into the housing recess 53 are formed on the both end surfaces, respectively. Each connecting projection 54 has a tapered shape in which the width along the radial direction of the rotor 21 increases toward the projecting tip (the tip in the circumferential direction).

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

  A separate core member 52 having a fan shape centered on the axis L of the rotating shaft 24 is housed in the housing 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). 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 different from each other. , On the same circle centered on the axis L.

  Both ends in the circumferential direction of the separate core member 52 have a flat shape along the radial direction, and face 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. The connecting concave portions 61 into which the connecting convex portions 54 of the core main body 51 are fitted are formed on both circumferential end surfaces of the separate core member 52. The separate core member 52 is fixed in the accommodation recess 53 by fitting each of the connection protrusions 54 into each of 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 housing recess 53, and the radial inner surface of the separate core member 52 and the diameter of the housing recess 53. A gap K3 is provided between the inner side surface and the direction. In addition, a gap K4 is provided between the connection recesses 61 and the connection protrusions 54 fitted in the connection recesses 61 in the circumferential direction. That is, the separate core member 52 is in contact with the core main body 51 side (the connection protrusion 54) only on both radial side surfaces of the connection recess 61.

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

  According to such a configuration, the separate core member 52 functions as a magnetic flux permitting portion that allows the generation of the field-weakening magnetic field substantially in the same manner as the inter-slit core portion 28 of the above-described embodiment. Rotation can be achieved. In the same configuration, the separate core member 52 is configured separately from the core main body 51 having the magnet magnetic poles Mn and Ms and the core magnetic poles Cn and Cs. Therefore, interference between the magnetic path of the field weakening magnetic flux (d-axis magnetic path) in the separate core member 52 and the magnetic path of the magnetic fluxes of the magnetic poles Mn and Ms in the core body 51 can be suppressed. As a result, the field flux weakened easily passes through the separate core member 52, which can further contribute to 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 main body 51, so that the separate core member 52 can be weakened and the field magnetic flux can more easily pass therethrough. As a result, it is possible to contribute to further higher rotation. In the components of the rotor core 23, at least the separate core member 52 is made of a material having a high magnetic permeability, and the core body 51 is made of an inexpensive iron material. Can be achieved.

  Further, 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 further reduces the influence of the magnetic flux of the magnet magnetic poles Mn and Ms. It is possible to adopt a configuration that is 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 fluxes of the magnet 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 connection protrusion 54 integrally formed with the core main 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 core member 51 and the separate core member 52.

  The connecting members 62 are 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 circumferential ends of each of the connecting members 62 are connected to the separate core member 52. Are fitted in connecting concave portions 63 and 64 formed on both circumferential end surfaces of the housing concave portion 53 in the circumferential direction. The connecting position of the connecting member 62 in the radial direction is set at the radial center position of the separate core member 52. Each connecting member 62 has a tapered shape whose radial width increases from the center in the circumferential direction to both ends in the circumferential direction. With this connecting member 62, the core main body 51 (housing 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, or the like) having a higher 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. By using a material having a higher magnetic resistance than the core body 51 and the separate core member 52 as a constituent material of the connecting member 62, the magnetic fluxes of the magnet magnetic poles Mn and Ms of the core body 51 pass through the connecting member 62 to separate cores. Flow to the member 52 side can be suppressed. As a result, interference of the magnetic fluxes of the magnet magnetic poles Mn and Ms with 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 accommodation recess 53 of the core main body 51 and the separate core member 52, but is not limited thereto. , And the filler may function as a connecting member that connects the core body 51 and the separate core member 52.

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

  Further, in the configuration as shown in FIGS. 9 and 10 described above, a cylindrical cover member that covers the outer peripheral surface of the rotor 21 may be provided. According to this, the falling off of the separate core member 52 from the core main body 51 can be suppressed by the cover member.

  In the above embodiment, the windings of 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 are connected in series, respectively. However, the winding mode may be appropriately changed. For example, as a modification, a U-phase winding will be described as an example. The U-phase windings U1 and U2 are connected in series, the U-phase windings U3 and U4 are connected in series, and the U-phase windings U1 and U2 are connected in series. And a series pair of U-phase windings U3 and U4 may be connected in parallel.

  In the above embodiment, the rotor 21 has eight poles and the number of the windings 13 of the stator 11 is twelve (that is, a motor configuration of eight poles and twelve slots). Can be appropriately changed according to the configuration.

  In the above embodiment, the number of the magnet magnetic poles Mn and the number of the core magnetic poles Cn are the same (two each) in, for example, the N pole of the rotor 21, but the numbers are not necessarily required to be the same. For example, three (or one) magnet magnetic poles Mn and one (or three) core magnetic poles Cn may be used. The same change may be made on the S pole side of the rotor (magnet pole Ms and core pole Cs).

  In the above embodiment, the core magnetic pole Cn and the core magnetic pole Cs are provided at the N pole and the S pole of the rotor 21, respectively. However, the present invention is not particularly limited thereto. For example, only one pole of the rotor 21 has the core magnetic pole. May be provided, and the other pole may be constituted entirely by magnet magnetic poles.

  In each of the magnetic poles Mn and Ms of the above embodiment, the pair of permanent magnets 22 buried in the rotor core 23 is arranged in a substantially V-shape that expands toward the outer peripheral side when viewed in the axial direction. However, the configuration of the permanent magnet in the magnetic poles Mn and Ms can be changed as appropriate. For example, a configuration in which one permanent magnet is provided for each magnet magnetic pole Mn, Ms may be adopted.

  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. The permanent magnet may be a surface magnet type structure (SPM structure) fixed to the outer peripheral surface of the rotor core 23.

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

  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. However, the present invention is not particularly limited to this, and the outer rotor type motor in which the rotor is arranged on the outer peripheral side of the stator 11. Motor may be embodied.

  In the above embodiment, the radial gap type motor 10 in which the stator 11 and the rotor 21 face in the radial direction is embodied. However, the present invention is not particularly limited to this, and the stator and the rotor face in the axial direction. The present invention may be applied to an axial gap type motor.

  -The above-mentioned embodiment and each modification may be combined suitably.

  Reference Signs List 10 motor, 11 stator, 12 stator core, 12a teeth, 13 winding, 21 rotor, 22 permanent magnet, 23 rotor core, 24 rotating shaft, 25 non-magnetic pole portion, 26a, 26b Slit portions (magnetic resistance portions), 28, 33: Core portions between slits (magnetic flux permitting portions), 32, 34: Auxiliary magnets, 51: Core body, 52: Separate core member, 62: Connecting member, K3: Air gap, Mn, Ms: magnetic poles, Cn, Cs: core magnetic poles, U1 to U4: U-phase winding, V1 to V4: V-phase winding, W1 to W4: W-phase winding.

Claims (12)

A motor in which a rotor rotates by receiving a rotating magnetic field generated by a drive current being supplied to a stator winding,
The winding is excited by the drive current at the same timing as each other, and includes a first winding and a second winding connected in series,
The rotor,
A magnetic pole having a permanent magnet;
A core magnetic pole comprising a part of a rotor core, wherein the magnet magnetic pole faces the second winding at a rotational position of the rotor facing the first winding;
It is configured such that a magnetic pole is formed by a part of the rotor core and is not formed by the magnet magnetic flux of the magnet magnetic pole, and the magnet magnetic pole faces the second winding at a rotational position of the rotor facing the first winding. And a magnetic flux permitting portion for permitting the generation of linkage flux by the field weakening current in the second winding. The motor according to claim 1,
The magnet pole and the core pole are provided on both the north pole and the south pole of the rotor, respectively.
The magnetic flux permitting portion is provided between the N core poles and the S core core poles in the circumferential direction of the rotor,
The motor, wherein the N-pole and S-pole core magnetic poles are adjacent to the different-pole magnet magnetic poles on the side opposite to the magnetic flux permitting portion in the circumferential direction. The motor according to claim 2,
A motor, wherein an opening angle of a surface of the magnet pole facing the stator is set larger than an opening angle of a surface of the core pole facing the stator. The motor according to claim 2 or 3,
A motor, wherein an opening angle of a surface of the magnetic flux permitting portion facing the stator is set to be larger than an opening angle of a surface of the core magnetic pole facing the stator. The motor according to any one of claims 2 to 4,
The motor, wherein the rotor core includes a magnetic resistance part between the magnetic flux permitting part and the core magnetic pole adjacent to each other. The motor according to claim 5,
The motor, wherein the magnetic resistance portion is a slit provided in the rotor core. The motor according to claim 6,
A motor, wherein an auxiliary magnet is provided in the slit. The motor according to any one of claims 2 to 7,
A motor, wherein an auxiliary magnet that allows a magnetic flux to flow through the core magnetic pole is embedded in a portion of the rotor core that is radially inner than the magnetic flux permitting portion. The motor according to any one of claims 1 to 8,
The rotor core includes a core main body having the magnet magnetic pole and the core magnetic pole, and a separate core member which is a separate component connected to the core main body and forms at least a part of the magnetic flux permitting portion. A motor characterized in that: The motor according to claim 9,
The motor, 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 provided on both the north pole and the south pole of the rotor, respectively.
The separate core member constituting the magnetic flux permitting portion is provided between the N core poles and the S core core poles in the circumferential direction of the rotor,
The core magnetic poles of the N pole and the S pole are each configured to be adjacent to the different magnetic poles on the opposite side to the separate core member in the circumferential direction,
A motor, wherein gaps are provided between the separate core member in the circumferential direction and the core magnetic poles of the north pole and the south pole. The motor according to any one of claims 9 to 11,
The motor, wherein the core body and the separate core member are connected to each other via a connection member made of a material having a higher magnetic resistance than the core body and the separate core member.

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