JP6181784B2 - Rotor and motor - Google Patents

Description

  The present invention relates to a rotor and a motor.

  The rotor used in the motor includes two rotor cores combined with each other having a plurality of claw-shaped magnetic poles in the circumferential direction, and a field magnet arranged between them, and each claw-shaped magnetic pole is alternately arranged. A so-called permanent magnet field Landell-type rotor that functions in different magnetic poles is known (see, for example, Patent Document 1).

  And in the rotor of patent document 1, the leakage magnetic flux in a rotor is reduced by adhering an auxiliary magnet to the surface inside radial direction of a claw-shaped magnetic pole.

Japanese Utility Model Publication No. 5-43749

  However, in the motor using the rotor as described above, although the leakage magnetic flux is reduced by the auxiliary magnet, further optimization as a rotor (high durability, low cost, high output, etc.) is achieved when commercializing the product. Is required.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a rotor that can be further optimized while including an auxiliary magnet, and a motor including the rotor. is there.

In the first aspect of the present invention, a plurality of claw-shaped magnetic poles protrude outward in the radial direction and extend in the axial direction at equal intervals on the outer periphery of the substantially disk-shaped core base. Are arranged between the first and second rotor cores in which claw-shaped magnetic poles are alternately arranged in the circumferential direction while the core bases are opposed to each other, and the claw-like shape of the first rotor core. A rotor including an axially magnetized field magnet that causes the magnetic pole to function as a first magnetic pole and the claw-shaped magnetic pole of the second rotor core to function as a second magnetic pole. An auxiliary magnet comprising an inter-pole magnet arranged between the circumferential direction and a back magnet arranged radially inside the claw-shaped magnetic pole is provided, and the auxiliary magnet and the field magnet have different characteristics. It constitutes than magnet, off the field magnet Together constitute from writing magnet, the auxiliary magnet, and summarized in that constructed from SmFeN magnets.

  According to this configuration, an auxiliary magnet is provided which includes an interpole magnet disposed between the claw-shaped magnetic poles in the circumferential direction and a back magnet disposed radially inward of the claw-shaped magnetic pole. Leakage magnetic flux can be reduced. Moreover, since the auxiliary magnet and the field magnet arranged between the axial directions of the core bases are composed of magnets having different characteristics, for example, high durability, low cost, and high output are achieved. Is possible.

Further, by configuring the field magnet from a ferrite magnet, for example, the cost can be easily reduced. By applying this configuration, the effects described in paragraph [0008] can be easily obtained.
Further, by configuring the auxiliary magnet from the SmFeN magnet, for example, it is possible to easily increase the durability and increase the output while reducing the cost compared to the case of configuring the auxiliary magnet from a neodymium magnet. By applying this configuration, the effects described in paragraph [0008] can be easily obtained.
In the invention described in claim 2, wherein the auxiliary magnet is summarized as the coercive force's go magnitude than the field magnet.
In this structure, the auxiliary magnet containing easily poles between the magnets provided affected by external magnetic fields on the outer peripheral side of the rotor, because had large coercivity than the field magnet, demagnetization early interpolar magnet Can be suppressed, and durability can be improved. Further, provided in the rotor less susceptible to external magnetic fields (hard to reach magnetic force demagnetized) field magnet is de a coercive force's go smaller than interpolar magnets, machining gap a field magnet Compared to a case where the magnet has the same coercive force as that of the magnet, the cost can be reduced. Thereby, cost reduction can be achieved, achieving high durability.

In the invention described in claim 3, wherein the auxiliary magnet is summarized as the residual magnetic flux density's go magnitude than the field magnet.
In this structure, the magnetic path length based on its magnetic force (as compared to the field magnet, etc.) auxiliary magnet containing short pole between magnets, because the residual magnetic flux density than the field magnet was large, the residual magnetic flux density A large magnet can be used efficiently, and as a result, high output can be efficiently achieved. That is, if a field magnet having a long magnetic path length based on its own magnetic force is composed of a magnet having a large residual magnetic flux density, the magnetic resistance and the leakage magnetic flux increase, so that a magnet having a large residual magnetic flux density can be used efficiently. As a result, it is impossible to increase the output efficiently, but conversely, a magnet having a large residual magnetic flux density can be used efficiently, and the output can be increased efficiently.

The gist of the invention according to claim 4 is that, in the rotor according to any one of claims 1 to 3 , the auxiliary magnet is constituted by a sheet-like magnet.
According to the same configuration, the auxiliary magnet is composed of a sheet-like magnet, which makes it easier to manufacture and lowers the cost compared to, for example, manufacturing a dedicated interpolar magnet baked into a cube. be able to.

The invention according to claim 5 is summarized as a motor including the rotor according to any one of claims 1 to 4 .
According to this configuration, the effect of the invention according to any one of claims 1 to 4 can be obtained in the motor.

  ADVANTAGE OF THE INVENTION According to this invention, the rotor and motor which can aim at the further optimization while providing an auxiliary magnet can be provided.

Sectional drawing of the motor in one Embodiment. The perspective view of the rotor in one Embodiment. The perspective view of the rotor in one Embodiment. Sectional drawing of the rotor in one Embodiment. (A) Aa sectional view in FIG. (B) bb sectional drawing in FIG. (C) cc sectional drawing in FIG.

Hereinafter, an embodiment embodying the present invention will be described with reference to FIGS.
As shown in FIG. 1, a motor case 2 of a motor 1 closes a cylindrical housing 3 formed in a bottomed cylindrical shape and an opening on the front side (left side in FIG. 1) of the cylindrical housing 3. And a front end plate 4. A circuit housing box 5 that houses a power circuit such as a circuit board is attached to an end of the cylindrical housing 3 on the rear side (right side in FIG. 1).

  A stator 6 is fixed to the inner peripheral surface of the cylindrical housing 3. The stator 6 includes an armature core 7 having a plurality of teeth extending radially inward, and a segment conductor (SC) winding 8 wound around the teeth of the armature core 7.

  The rotor 11 of the motor 1 has a rotating shaft 12 and is disposed inside the stator 6. The rotating shaft 12 is a non-magnetic metal shaft, and is rotatably supported by bearings 13 and 14 supported by the bottom 3 a of the cylindrical housing 3 and the front end plate 4.

  2 to 4, the rotor 11 includes first and second rotor cores 21 and 22, an annular magnet 23 (see FIG. 4) as a field magnet, and first and second magnets as an auxiliary magnet and a back magnet. Second backside auxiliary magnets 24, 25 and first and second interpole magnets 26, 27 as auxiliary magnets and interpole magnets are provided.

  The first rotor core 21 has first claw-shaped magnetic poles 21b as a plurality of claw-shaped magnetic poles (seven in the present embodiment) at regular intervals on the outer periphery of the first core base 21a as a substantially disk-shaped core base. Projecting radially outward and extending in the axial direction. The circumferential end surfaces 21c and 21d of the first claw-shaped magnetic pole 21b are flat surfaces extending in the radial direction (not inclined with respect to the radial direction when viewed from the axial direction), and the first claw-shaped magnetic pole 21b has a cross section perpendicular to the axis. Has a fan shape. The circumferential width (angle) of each first claw-shaped magnetic pole 21b, that is, the width (angle) of the circumferential end faces 21c and 21d is the width of the gap between the first claw-shaped magnetic poles 21b adjacent in the circumferential direction ( (Angle) is set smaller.

  Further, the second rotor core 22 has the same shape as the first rotor core 21, and a plurality of (seven in this embodiment) are arranged at equal intervals on the outer periphery of the second core base 22a as a substantially disk-shaped core base. The second claw-shaped magnetic pole 22b as a claw-shaped magnetic pole protrudes radially outward and extends in the axial direction. In addition, the circumferential end faces 22c and 22d of the second claw-shaped magnetic pole 22b are flat surfaces extending in the radial direction (not inclined with respect to the radial direction when viewed from the axial direction), and the second claw-shaped magnetic pole 22b is orthogonal to the axis. The direction cross section has a fan shape. Further, the circumferential width (angle) of each second claw-shaped magnetic pole 22b, that is, the width (angle) of the circumferential end faces 22c, 22d is the width of the gap between the second claw-shaped magnetic poles 22b adjacent in the circumferential direction ( (Angle) is set smaller. The second rotor core 22 is disposed between the first claw-shaped magnetic poles 21b corresponding to the second claw-shaped magnetic poles 22b (that is, alternately in the circumferential direction with the first claw-shaped magnetic poles 21b). As shown in FIG. 4, the annular magnet 23 is assembled (attached) to the first rotor core 21 so as to be disposed (sandwiched) between the axial directions of the first core base 21a and the second core base 22a facing each other.

  The outer diameter of the annular magnet 23 is set to be the same as the outer diameters of the first and second core bases 21a and 22a, and the first claw-shaped magnetic pole 21b functions as the first magnetic pole (N pole in the present embodiment). The second claw-shaped magnetic pole 22b is magnetized in the axial direction so as to function as a second magnetic pole (S pole in the present embodiment).

  Also, as shown in FIGS. 3, 4 and 5C, the first claw-shaped magnetic pole 21b has a back surface (radially inner surface) between the second core base 22a and the outer peripheral surface. 1 A back auxiliary magnet 24 is arranged. The first back auxiliary magnet 24 has a fan-shaped cross section in the axis-perpendicular direction, and the second core base 22a has a side that abuts on the back of the first claw-shaped magnetic pole 21b as an N pole having the same polarity as the first claw-shaped magnetic pole 21b. Is magnetized in the radial direction so that the side in contact with the second core base 22a has the same polarity as that of the second core base 22a.

  Further, as shown in FIGS. 2, 4 and 5A, the second claw-shaped magnetic pole 22b has a back surface (a radially inner surface) and an outer peripheral surface of the first core base 21a. Two rear auxiliary magnets 25 are arranged. The second back auxiliary magnet 25 has a fan-shaped cross section in the direction perpendicular to the axis, and the first core base 21a has a side that contacts the back surface of the second claw-shaped magnetic pole 22b as the S pole having the same polarity as the second claw-shaped magnetic pole 22b. Is magnetized in the radial direction so that the side in contact with the first core base 21a has the same polarity as that of the first core base 21a.

  Further, as shown in FIG. 4, the first back auxiliary magnet 24 and the second back auxiliary magnet 25 overlap each other in the axial direction at the axial position where the annular magnet 23 is arranged. It is set so as to be arranged also at the arranged axial position.

  That is, in the range of A1 shown in FIG. 2, as shown in FIG. 5A, a rotor structure in which magnetic flux flows from the second back auxiliary magnet 25 toward the arrow is obtained. Further, in the range of A2 shown in FIG. 2, as shown in FIG. 5B, the permanent magnets having different magnetic poles alternately arranged in the circumferential direction are arranged by the first and second back auxiliary magnets 24 and 25. E) It has the same structure as the rotor. Further, in the range of A3 shown in FIG. 2, as shown in FIG. 5C, the rotor structure is such that magnetic flux flows from the first back auxiliary magnet 24 toward the arrow.

  In addition, first and second interpole magnets 26 and 27 are arranged between the first claw-shaped magnetic pole 21b and the second claw-shaped magnetic pole 22b in the circumferential direction. Specifically, the first interpole magnet 26 of the present embodiment includes a flat surface formed by one circumferential end surface 21c of the first claw-shaped magnetic pole 21b and the circumferential end surface of the first back auxiliary magnet 24; The other claw-shaped magnetic pole 22b is disposed between the other circumferential end surface 22d and the flat surface formed by the circumferential end surface of the second back auxiliary magnet 25 (so as to fill all gaps). The second interpole magnet 27 of the present embodiment includes a flat surface formed by the other circumferential end surface 21d of the first claw-shaped magnetic pole 21b and the circumferential end surface of the first back auxiliary magnet 24, and The two claw-shaped magnetic poles 22b are arranged between the one circumferential end surface 22c and the flat surface formed by the circumferential end surface of the second back auxiliary magnet 25 (so as to fill all gaps). The first and second interpole magnets 26 and 27 have the same magnetic pole as that of the first and second claw-shaped magnetic poles 21b and 22b (the first claw-shaped magnetic pole 21b side is the N pole, and the second claw-shaped magnet It is magnetized in the circumferential direction (so that the magnetic pole 22b side becomes the S pole).

  At least one of the auxiliary magnets (first and second backside auxiliary magnets 24 and 25 and first and second interpole magnets 26 and 27) and the annular magnet 23 are composed of magnets having different characteristics. Yes.

  Specifically, the first and second interpole magnets 26 and 27 of the present embodiment are composed of magnets having larger coercive force and residual magnetic flux density (magnetomotive force) than the annular magnet 23. Specifically, the annular magnet 23 is composed of a ferrite magnet. The first and second interpole magnets 26 and 27 are rare earth magnets, more specifically, neodymium magnets.

Further, the first and second back auxiliary magnets 24 and 25 of the present embodiment are composed of ferrite magnets having the same coercive force and residual magnetic flux density as the annular magnet 23.
Next, the operation of the motor 1 configured as described above will be described.

  In the rotor 11, by providing auxiliary magnets (first and second back auxiliary magnets 24, 25 and first and second interpole magnets 26, 27), leakage magnetic flux is reduced at each arrangement location, and consequently The magnetic flux of the annular magnet 23 can be effectively used for the output of the motor 1.

Next, the characteristic effects of the above embodiment will be described below.
(1) The first and second interpole magnets 26 and 27 which are provided on the outer peripheral side of the rotor 11 and are easily affected by an external magnetic field are magnets (neodymium magnets) having a larger coercive force than the annular magnet 23 (ferrite magnet). Since it comprised more, it can suppress that the 1st and 2nd interpole magnets 26 and 27 demagnetize early, and can improve durability. Further, the annular magnet 23 provided inside the rotor 11 and hardly affected by an external magnetic field (a magnetic force for demagnetization is difficult to reach) is made to be more than the first and second interpole magnets 26 and 27 (neodymium magnet 9). By constituting from a magnet having a small coercive force (ferrite magnet), it is possible to reduce the cost compared to the case where the annular magnet 23 is constructed from magnets having the same coercive force as the first and second interpole magnets 26 and 27. . Thereby, cost reduction can be achieved, achieving high durability.

  (2) The first and second interpole magnets 26 and 27 having a short magnetic path length based on their own magnetic force (compared to the annular magnet 23 or the like) have a larger residual magnetic flux density than the annular magnet 23 (ferrite magnet). Since it is composed of (neodymium magnet), a magnet having a large residual magnetic flux density can be used efficiently, and as a result, high output can be efficiently achieved. That is, when the annular magnet 23 having a long magnetic path length based on its own magnetic force is configured from a magnet having a large residual magnetic flux density, the magnetic resistance and the leakage magnetic flux increase, so that a magnet having a large residual magnetic flux density can be used efficiently. As a result, it is impossible to increase the output efficiently, but conversely, a magnet having a large residual magnetic flux density can be used efficiently, and the output can be increased efficiently.

  (3) Since the first and second back auxiliary magnets 24 and 25 are composed of magnets (ferrite magnets) having a smaller coercive force than the first and second interpole magnets 26 and 27 (neodymium magnets), for example, the first And compared with the case where the 2nd back auxiliary magnets 24 and 25 are comprised from the magnet (neodymium magnet) of the same coercive force as the 1st and 2nd interpole magnets 26 and 27, it can be made cheap.

The above embodiment may be modified as follows.
In the above embodiment, the annular magnet 23 and the first and second back auxiliary magnets 24 and 25 are made of ferrite magnets having the same characteristics, and the first and second interpole magnets 26 and 27 are made of neodymium magnets. Although it comprised, you may change the magnet (type and characteristic) which comprises them.

  For example, the first and second interpole magnets 26 and 27 of the above-described embodiment may be composed of rare earth magnets other than neodymium magnets (for example, samarium cobalt magnets). Even if it does in this way, the effect similar to the effect of the said embodiment can be acquired.

  Further, for example, the first and second interpole magnets 26 and 27 of the above-described embodiment may be composed of SmFeN magnets. Even if it does in this way, the effect similar to the effect of the said embodiment can be acquired. Moreover, it can be made cheaper compared with the case where the 1st and 2nd interpole magnets 26 and 27 are comprised from the neodymium magnet.

  Further, for example, the first and second interpole magnets 26 and 27 of the above-described embodiment may be configured by sheet-like magnets. The sheet-like magnet is a sheet-like so-called rubber magnet or magnet sheet, and may be disposed between the first claw-shaped magnetic pole 21b and the second claw-shaped magnetic pole 22b by increasing the thickness by overlapping. However, in particular when embodied in a small motor 1, one sheet may be disposed between the first claw-shaped magnetic pole 21b and the second claw-shaped magnetic pole 22b. In this case, for example, compared with the case of producing a dedicated interpole magnet (first and second interpole magnets 26 and 27) baked into a cube, the manufacture is facilitated and the cost is reduced. Can do.

  Further, for example, the first and second back auxiliary magnets 24, 25 of the above embodiment may be constituted by magnets having a larger residual magnetic flux density than the annular magnet 23. Specifically, the first and second back auxiliary magnets 24 and 25 may be composed of, for example, a ferrite magnet having a higher residual magnetic flux density (higher grade) than the annular magnet 23, or a rare earth magnet (neodymium magnet). Or a samarium-cobalt magnet or a SmFeN magnet). If it does in this way, it can be set as a high output compared with the case where the 1st and 2nd back auxiliary magnets 24 and 25 are comprised from the magnet of the same residual magnetic flux density as the annular magnet 23 (the said embodiment), for example.

  In addition, for example, the first and second back auxiliary magnets 24 and 25 of the above-described embodiments have the same characteristics as the first and second interpole magnets 26 and 27 (neodymium magnet, samarium cobalt-based magnet, SmFeN magnet, etc.). You may comprise from a magnet.

  Further, for example, the first and second interpole magnets 26 and 27 and the annular magnet 23 are made of magnets having the same characteristics, and only the first and second back auxiliary magnets 24 and 25 are made of magnets having different characteristics. May be.

  For example, you may comprise the annular magnet 23 of said each embodiment from magnets other than a ferrite magnet. For example, you may comprise from the neodymium magnet whose coercive force and residual magnetic flux density are smaller (low grade) than the 1st and 2nd interpole magnets 26 and 27 (neodymium magnet).

  In addition to the combination of the above embodiments (the above embodiment and other examples), the annular magnet 23, the first and second back auxiliary magnets 24, depending on the purpose (for example, the desired balance between cost and output), 25, the magnet constituting at least one of the first and second interpole magnets 26, 27 may be changed to one having different characteristics.

  In the above embodiment, the rotor 11 includes the back magnet (first and second back auxiliary magnets 24 and 25) and the interpole magnets (first and second interpole magnets 26 and 27) as the auxiliary magnets. However, the present invention is not limited to this, and the rotor may be changed to one having only one of the back magnet and the interpole magnet. Of course, in this case, the auxiliary magnet (back magnet or inter-pole magnet) and the annular magnet 23 are composed of magnets having different characteristics.

The technical idea that can be grasped from the above embodiment will be described below together with the effects thereof.
(A) The back magnet as the auxiliary magnet provided on the radially inner side of the claw-shaped magnetic pole is composed of a magnet having a smaller coercive force than the interpolar magnet.

  According to the same configuration, the back magnet as an auxiliary magnet provided on the radially inner side of the claw-shaped magnetic pole is formed of a magnet having a smaller coercive force than the interpole magnet. For example, the back magnet is the same as the interpole magnet. Compared to the case of a coercive magnet, the cost can be reduced.

(B) The back magnet as the auxiliary magnet provided on the radially inner side of the claw-shaped magnetic pole is composed of a magnet having a larger residual magnetic flux density than the field magnet.
According to the same configuration, the back magnet as the auxiliary magnet provided on the radially inner side of the claw-shaped magnetic pole is composed of a magnet having a larger residual magnetic flux density than the field magnet. Compared with the case where the magnets have the same residual magnetic flux density, the output can be increased.

  A plurality of claw-shaped magnetic poles projecting radially outward and extending in the axial direction on the outer periphery of each substantially disk-shaped core base, and extending in the axial direction, with the claw-shaped magnetic poles facing each other. Are arranged between the first and second rotor cores arranged alternately in the circumferential direction and the axial directions of the core bases, and are magnetized in the axial direction, so that the claw-shaped magnetic poles of the first rotor core are And a field magnet that allows the claw-shaped magnetic pole of the second rotor core to function as the second magnetic pole, and the auxiliary magnet is interposed between the claw-shaped magnetic poles in the circumferential direction. The gist is that an interpole magnet is provided as a magnet, and the interpole magnet is formed of a magnet having a larger coercive force than the field magnet.

  According to this configuration, since the auxiliary magnet (interpolar magnet) is provided between the circumferential directions of the claw-shaped magnetic poles, the leakage magnetic flux in the rotor can be reduced. Moreover, since the interpole magnet and the field magnet arranged between the axial directions of the core bases are composed of magnets having different characteristics, for example, high durability, low cost, and high output are achieved. Can be realized.

  According to this configuration, the interpole magnet provided on the outer peripheral side of the rotor and susceptible to the influence of an external magnetic field is composed of a magnet having a coercive force larger than that of the field magnet. Can be suppressed, and durability can be improved. In addition, a field magnet that is provided inside the rotor and is not easily affected by an external magnetic field (a magnetic force for demagnetization is difficult to reach) is composed of a magnet having a smaller coercive force than an interpole magnet. Can be made cheaper than the case where is made of a magnet having the same coercive force as that of the interpole magnet. Thereby, cost reduction can be achieved, achieving high durability.

  A plurality of claw-shaped magnetic poles projecting radially outward and extending in the axial direction on the outer periphery of each substantially disk-shaped core base, and extending in the axial direction, with the claw-shaped magnetic poles facing each other. Are arranged between the first and second rotor cores arranged alternately in the circumferential direction and the axial directions of the core bases, and are magnetized in the axial direction, so that the claw-shaped magnetic poles of the first rotor core are And a field magnet that allows the claw-shaped magnetic pole of the second rotor core to function as the second magnetic pole, and the auxiliary magnet is interposed between the claw-shaped magnetic poles in the circumferential direction. The gist is that an interpole magnet is provided as a magnet, and the interpole magnet is formed of a magnet having a larger residual magnetic flux density than the field magnet.

  According to this configuration, since the auxiliary magnet (interpolar magnet) is provided between the circumferential directions of the claw-shaped magnetic poles, the leakage magnetic flux in the rotor can be reduced. Moreover, since the interpole magnet and the field magnet arranged between the axial directions of the core bases are composed of magnets having different characteristics, for example, high durability, low cost, and high output are achieved. Can be realized.

  According to this configuration, the interpole magnet having a short magnetic path length (compared to a field magnet or the like) based on its own magnetic force is composed of a magnet having a higher residual magnetic flux density than the field magnet. Magnets can be used efficiently, and as a result, high output can be efficiently achieved. That is, if a field magnet having a long magnetic path length based on its own magnetic force is composed of a magnet having a large residual magnetic flux density, the magnetic resistance and the leakage magnetic flux increase, so that a magnet having a large residual magnetic flux density can be used efficiently. As a result, it is impossible to increase the output efficiently, but conversely, a magnet having a large residual magnetic flux density can be used efficiently, and the output can be increased efficiently.

  A back auxiliary magnet as an auxiliary magnet is provided on the radially inner side of the claw-shaped magnetic pole, and the back auxiliary magnet is composed of a magnet having the same characteristics as the interpole magnet.

  DESCRIPTION OF SYMBOLS 11 ... Rotor, 21 ... 1st rotor core, 21a ... 1st core base (core base), 21b ... 1st claw-shaped magnetic pole (claw-shaped magnetic pole), 22 ... 2nd rotor core, 22a ... 2nd core base (core base) 22b ... second claw-shaped magnetic pole (claw-shaped magnetic pole), 23 ... annular magnet (field magnet), 24 ... first back auxiliary magnet (auxiliary magnet), 25 ... second back auxiliary magnet (auxiliary magnet), 26 ... First interpolar magnet (auxiliary magnet and interpolar magnet), 27 ... second interpolar magnet (auxiliary magnet and interpolar magnet).

Claims (5)

A plurality of claw-shaped magnetic poles are projected radially outward at equal intervals on the outer peripheral portion of the substantially disk-shaped core base, and are formed in a claw shape with the core bases facing each other. First and second rotor cores in which magnetic poles are alternately arranged in the circumferential direction;
Arranged between the axial directions of the core bases, the claw-shaped magnetic pole of the first rotor core functions as a first magnetic pole, and the claw-shaped magnetic pole of the second rotor core functions as a second magnetic pole. A rotor comprising a field magnet magnetized in the axial direction,
An interpole magnet disposed between the claw-shaped magnetic poles in the circumferential direction, and an auxiliary magnet composed of a back magnet disposed on the radial inner side of the claw-shaped magnetic pole,
The auxiliary magnet and the field magnet are composed of magnets having different characteristics ,
A rotor characterized in that the field magnet is composed of a ferrite magnet, and the auxiliary magnet is composed of an SmFeN magnet . The rotor according to claim 1, wherein
The auxiliary magnet rotor characterized by the coercive force's go magnitude than the field magnet. The rotor according to claim 1 or 2,
The auxiliary magnet rotor characterized by the residual magnetic flux density's go magnitude than the field magnet. The rotor according to any one of claims 1 to 3 ,
A rotor characterized in that the auxiliary magnet is composed of a sheet magnet. Motor comprising the rotor according to any one of claims 1 to 4.