motor

Abstract

The present invention provides a motor for increasing the cogging torque. The motor (1) comprises: a rotating shaft (30); a magnetic component (20) having a core (2) and a coil (3), wherein the core (2) has an annular portion (2a) and a plurality of spokes (2b); and a magnet (11), wherein the magnetic component (20) and the magnet (11) are arranged on the inner side of one side, and the ends of the plurality of spokes (2b) are opposed to the magnet (11) in the radial direction nm, and the core (2) has a pair of magnetic pole portions (2c) extending in two directions of the circumferential direction xy at the ends of the plurality of spokes (2b), and the magnetic pole portion (2c-1x) on the x side of a pair of magnetic pole portions (2c-1) of at least one of the plurality of spokes (2b) has a larger magnetic resistance than the magnetic pole portion (2c-1y) on the y side of the other side.

Description

Technical Field

[0001] The present invention relates to a motor. Background Art

[0002] As a DC motor used for information equipment, vehicle-mounted use, etc., for example, Patent Document 1 describes a structure in which a magnet is not integrally molded but is composed of four magnets. Also, Patent Document 2 describes the use of an integrally molded magnet.

[0003] In such a DC motor, it is desirable to further reduce vibration, and generally, the cogging torque, which is one of the causes of vibration, is suppressed as much as possible.

[0004] On the other hand, it is desirable to suppress the rotation of the shaft of the motor when the motor is stopped, such as for a motor used in a vehicle electric door or electric hatch gate. In order to suppress the rotation of the shaft of the motor when stopped, it is effective to increase the cogging torque instead.

[0005] As a technology for increasing the cogging torque, the technology described in Patent Document 3 is disclosed. The technology described in Patent Document 3 is a DC motor having: four excitation magnetic poles; and an armature core having five teeth extending radially from a shaft and facing the excitation magnetic poles, and having a slot at the center of the opening angle of the outer peripheral surface of the top end of each tooth of the armature core, in which the air gap between the excitation magnetic pole and the armature core is enlarged. Due to the presence of the air gap, when the driving voltage is not applied, the relative positional relationship between the excitation magnetic pole and the armature core is in a stable state, so that the cogging torque is increased.

[0006] However, in the technology described in Patent Document 3, the number of excitation poles is limited to four, and the number of teeth of the armature core is limited to five. In addition, it should be noted that according to this technology, the effect of increasing the cogging torque is not sufficient, and it is ideal to generate a larger cogging torque.

[0007] Prior art literature

[0008] Patent Literature

[0009] Patent Document 1: Japanese Patent Application Laid-Open No. 11-103552

[0010] Patent Document 2: Japanese Patent Application Publication No. 2008-306844

[0011] Patent Document 3: Japanese Patent Application Laid-Open No. 1-91640 Summary of the invention

[0012] Problem that the invention aims to solve

[0013] Therefore, an object of the present invention is to provide a motor that achieves an increase in cogging torque.

[0014] Solutions for solving problems

[0015] The above problems are solved by the following present invention. That is, the motor of the present invention comprises: a rotating shaft;

[0016] a magnetic member having a core and a coil wound around spokes, wherein the core has an annular portion disposed coaxially with the rotation shaft and a plurality of spokes extending radially from the annular portion; and

[0017] The magnet is arranged in a ring shape coaxially with the rotating shaft.

[0018] The magnetic member and the magnet are arranged on the inner side of one of them in the radial direction.

[0019] The radial ends of each of the plurality of spokes are radially opposed to the magnet,

[0020] The core has a pair of magnetic pole portions extending in two circumferential directions at radial ends of each of the plurality of spokes.

[0021] Of the pair of magnetic pole portions included in at least one of the plurality of spokes, the magnetic pole portion on one side in the circumferential direction has a larger magnetic resistance than the magnetic pole portion on the other side in the circumferential direction.

[0022] In the present invention, it is preferred that the spoke having the pair of magnetic pole portions having different magnetic resistances on one side and the other side in the circumferential direction among the plurality of spokes is set as a first spoke, and the other spokes adjacent to the first spoke on the one side in the circumferential direction are set as a second spoke.

[0023] Of the pair of magnetic pole portions included in the second spoke, the magnetic pole portion on the other side in the circumferential direction has a larger magnetic resistance than the magnetic pole portion on the one side in the circumferential direction.

[0024] Furthermore, in the present invention, it is preferred that another spoke adjacent to the second spoke on one side in the circumferential direction is set as a third spoke.

[0025] The magnetic pole portion on the other side in the circumferential direction of the pair of magnetic pole portions included in the third spoke has a smaller magnetic resistance than the magnetic pole portion on the other side in the circumferential direction of the pair of magnetic pole portions included in the second spoke.

[0026] In the present invention, preferably, when the plurality of spokes is an even number,

[0027] The other spokes among the plurality of spokes that are located at a point symmetrically with respect to the first spoke and the rotation axis as the center are defined as fourth spokes, and the other spokes that are located at a point symmetrically with respect to the second spoke and the rotation axis as the center are defined as fifth spokes,

[0028] The magnetic pole portion on the one side of the pair of magnetic pole portions of the fourth spoke has a larger magnetic resistance than the magnetic pole portion on the other side of the circumferential direction.

[0029] Of the pair of magnetic pole portions included in the fifth spoke, the magnetic pole portion on the other side in the circumferential direction has a larger magnetic resistance than the magnetic pole portion on the one side in the circumferential direction.

[0030] In the present invention, a preferred solution is that when the plurality of spokes is an odd number,

[0031] The other spokes among the plurality of spokes that are located at a point symmetrically with respect to the narrow groove between the first spoke and the second spoke, with the rotation axis as the center, are referred to as fourth a spokes,

[0032] The other two spokes adjacent to the fourth a-spoke on both sides of the circumferential direction are set as the third a-spoke and the fifth a-spoke,

[0033] The magnetic resistance of the two magnetic poles of the pair of magnetic poles of the fourth spoke a is substantially equal.

[0034] At least one of the magnetic pole portion on the circumferential side of the fourth a-spoke in the pair of magnetic pole portions of the third a-spoke and the magnetic pole portion on the circumferential side of the fourth a-spoke in the pair of magnetic pole portions of the fifth a-spoke has a smaller magnetic resistance than one of the magnetic pole portions of the pair of magnetic pole portions of the fourth a-spoke.

[0035] In addition, in the present invention, another preferred solution is that, when the plurality of spokes is an odd number, the other spokes among the plurality of spokes that are located at a point symmetrical position with respect to the narrow groove between the first spoke and the second spoke and centered on the rotation axis are set as fourth b spokes,

[0036] The magnetic pole portion on one side or the other side of the pair of magnetic pole portions of the fourth b-spoke has a larger magnetic resistance than the magnetic pole portion on the opposite side.

[0037] The other spoke adjacent to the fourth b-spoke on the magnetic pole portion side with smaller magnetic resistance among the pair of magnetic pole portions included in the fourth b-spoke in the circumferential direction is set as a third b-spoke,

[0038] The magnetic pole portion on the fourth b-spoke side in the circumferential direction of the pair of magnetic pole portions of the third b-spoke has a smaller magnetic resistance than the one magnetic pole portion of the pair of magnetic pole portions of the first spoke. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 is a cross-sectional view (transverse cross-sectional view) of a motor according to a first embodiment of the present invention, taken along a plane perpendicular to the axis. Figure 2 AA section view in.

[0040] Figure 2 is a cross-sectional view of a plane including the shaft of the motor of the first embodiment, Figure 1 BB section view in.

[0041] Figure 3 This is a cross-sectional view showing only the rotor core and the rotation shaft of the motor according to the first embodiment.

[0042] Figure 4 It is a cross-sectional view (transverse cross-sectional view) of a motor of a conventional example taken along a plane perpendicular to the axis, and is a diagram for explaining a mechanism of generation of cogging torque.

[0043] Figure 5 is with Figure 1 The cross-sectional view (transverse cross-sectional view) of the motor of the first embodiment taken along a plane perpendicular to the axis is a diagram for explaining the mechanism of generation of the cogging torque.

[0044] Figure 6 This is a cross-sectional view showing only the rotor core and the rotation shaft of the motor according to the second embodiment.

[0045] Figure 7 This is a cross-sectional view showing only the rotor core and the rotation shaft of the motor according to the third embodiment.

[0046] Figure 8 This is a cross-sectional view showing only the rotor core and the rotation shaft of the motor according to the fourth embodiment.

[0047] Fig. 9 This is a cross-sectional view showing only the rotor core and the rotation shaft of the motor according to the fifth embodiment.

[0048] Fig.10 This is a cross-sectional view showing only the rotor core and the rotation shaft of the motor according to the sixth embodiment.

[0049] Fig.11 This is a cross-sectional view showing only the rotor core and the rotation shaft of the motor according to the seventh embodiment.

[0050] Fig.12 is a cross-sectional view (transverse cross-sectional view) of a motor according to an eighth embodiment of the present invention, taken along a plane perpendicular to the axis. Fig.13 CC section view in.

[0051] Fig.13 is a cross-sectional view of a plane including the shaft of the motor according to the eighth embodiment, Fig.12 DD section view in.

[0052] Fig.14This is a cross-sectional view showing only a stator core extracted from the motor according to the eighth embodiment.

[0053] Fig.15 It is a cross-sectional view (transverse cross-sectional view) taken along a plane perpendicular to the axis of a motor according to a ninth embodiment as an example of the present invention.

[0054] Fig.16 It is a cross-sectional view showing only a stator core extracted from a motor according to a ninth embodiment.

[0055] Fig.17 This is an enlarged view of the periphery of the tip end portion of each spoke in the motor according to the ninth embodiment. DETAILED DESCRIPTION

[0056] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0057] [First embodiment]

[0058] Figure 1 1 is a cross-sectional view of a motor 1 according to a first embodiment of the present invention, taken along a plane perpendicular to the axis. Figure 2 It is a cross-sectional view of a plane including the axis. Figure 1 yes Figure 2 AA section view in the figure, Figure 2 yes Figure 1 BB section view in.

[0059] The motor 1 of the present embodiment is a motor called a "square motor" or a "square DC motor" and has a substantially quadrilateral (substantially regular quadrilateral) cross section. In addition, the motor 1 of the present embodiment has a magnet 11 that is generally cylindrical and functions as an excitation magnet. The magnet 11 has an integral structure in which the shape of the outer periphery in the side section perpendicular to the rotating shaft 30 is a substantially regular quadrilateral (square) with rounded corners and the shape of the inner periphery in the same side section is a circle. The magnet 11 is arranged to surround the rotor 20 described later, and a cylindrical portion 12 that also serves as a frame is arranged on the outer periphery of the magnet 11.

[0060] The cylindrical portion 12 is a magnetic body such as an iron material, and is arranged to be in contact with the outer periphery of the magnet 11, and the shape of the inner periphery in the side section perpendicular to the rotating shaft 30 has a substantially regular quadrilateral cylindrical shape that is substantially the same shape as the outer periphery of the magnet 11. The stator 10 is constituted by these magnets 11 and the cylindrical portion 12. The openings at both ends of the cylindrical portion 12 are closed by the cover portion 50 and the bottom portion 60, respectively.

[0061] It should be noted that in this embodiment, when the term "radial direction" is used, it refers to the radial direction of a circle with the rotation axis 30 as the axis, and when the term "circumferential direction" is used, it refers to the circumferential direction of a circle with the rotation axis 30 as the axis. Figure 1 For example, the arrow m direction as the outward direction and the arrow n direction as the inward direction are set as radial directions (hereinafter, sometimes referred to as "radial directions mn"), and the arrow x direction as the clockwise direction and the arrow y direction as the counterclockwise direction are set as circumferential directions (hereinafter, sometimes referred to as "circumferential directions xy"). Figure 1 The direction of arrow u in FIG. 1 is set as the upward direction u, and the direction of arrow d is set as the downward direction d. The upward direction u and the downward direction d are not necessarily consistent with the vertical direction of the gravity direction. The terms representing these directions and these reference numerals are the same in other drawings.

[0062] An iron rotor core (core) 2 is arranged at a predetermined gap inside the magnet 11. A rotating shaft 30 is fixed at the center of the rotor core 2. The rotor core 2 is a laminate of silicon steel plates, etc., and has an annular portion 2a surrounding the rotating shaft 30 and six spokes 2b extending radially (radially) from the annular portion 2a with the rotating shaft 30 as the axis.

[0063] The rotor core 2 has a pair of magnetic poles extending in two directions of the circumferential xy at the ends of each of the plurality of (six) spokes 2b in the radial direction mn (especially, in the outer direction m) (hereinafter, a pair of magnetic poles is sometimes collectively referred to as a "pair of magnetic poles". In the present embodiment, when a pair of magnetic poles is collectively referred to as a "pair of magnetic poles", the reference numeral "2c" or the reference numeral "2c-□" (□ is an integer) is marked. A rotor coil (coil) 3 is wound around each of the six spokes 2b. In addition, the rotor core 2 and the rotor coil 3 constitute a rotor (magnetic component) 20.

[0064] The rotating shaft 30 is rotatably supported at both ends by a first bearing 40 and a second bearing 41. The first bearing 40 is fixed to the cover 50, and the second bearing 41 is fixed to the bottom 60. The rotor 20 is fixed to the stator 10 via these bearings 40 and 41. The rotor 20 is rotatable relative to the stator 10.

[0065] A brush power supply mechanism (not shown) is disposed on the rotating shaft 30, and the brush power supply mechanism supplies driving current to the rotor coil 3 wound around the rotor core 2. The mechanical and electrical structures of the rotor 20 are the same as those of a general DC brush motor.

[0066] Figure 3 This is a cross-sectional view of the motor 1 according to the present embodiment in which only the rotor core 2 and the rotating shaft 30 are extracted. Figure 3 In the rotor core 2 shown, the shapes of a pair of magnetic pole portions 2c-1x to 2c-6x, 2c-1y to 2c-6y possessed by at least one spoke (in the present embodiment, all spokes 2b-1 to 2b-6) among an even number of spokes (six spokes in the present embodiment) 2b-1 to 2b-6 are different from each other.

[0067] The following will be described in more detail.

[0068] First, in Figure 3 The spoke extending from the annular portion 2a in the upward direction u is set as the first spoke 2b-1, and the second spoke 2b-2, the third spoke 2b-3, the fourth spoke 2b-4, the fifth spoke 2b-5 and the sixth spoke 2b-6 are sequentially set from the first spoke 2b-1 in the clockwise direction x.

[0069] In the first spoke 2b-1, in the magnetic pole pair 2c-1 at the end in the outer direction m, a groove 2ch extending parallel to the axial direction of the rotating shaft 30 is provided on the surface facing the magnet 11. Figure 3 As shown in FIG. 1 , the groove portion 2ch is located in the magnetic pole portion pair 2c-1 at a position deviated from the center in the circumferential direction xy to the clockwise x side (the second spoke 2b-2 side). Figure 3 As shown, the cross-sectional area of ​​the magnetic pole portion 2c-1x on the clockwise x side of the magnetic pole portion pair 2c-1 is small, and the cross-sectional area of ​​the magnetic pole portion 2c-1y on the counterclockwise y side is large.

[0070] The cross-sectional area of ​​the cross section of the magnetic pole portions 2c-1x, 2c-1y is the cross-sectional area of ​​the path through which the magnetic flux passes.

[0071] In addition, magnetic resistance (reluctance) Rm is expressed by the following equation (1).

[0072] Rm=L / μA···Formula (1)

[0073] (In the above formula (1), L represents the length of the magnetic path, A represents the cross-sectional area, and μ represents the magnetic permeability)

[0074] That is, if the cross-sectional area μ located in the denominator on the right side of formula (1) is small, the magnetic resistance Rm is large (hereinafter, large magnetic resistance is sometimes referred to as "high" and indicated by the figure mark "H"); if the cross-sectional area μ is large, the magnetic resistance Rm is small (hereinafter, small magnetic resistance Rm is sometimes referred to as "low" and indicated by the figure mark "L").

[0075] In the magnetic pole pair 2c-1, if the position of the groove 2ch is deviated from the center in the circumferential direction xy, compared with the case where it is located at the center, as shown in FIG. Figure 3 As shown, the magnetic resistance Rm of the magnetic pole portion 2c-1x on the side close to the groove portion 2ch is large (reference symbol H), and the magnetic resistance Rm of the magnetic pole portion 2c-1y on the side away from the groove portion 2ch is small (reference symbol L).

[0076] Therefore, in the first spoke 2b-1, the magnetic pole portion 2c-1x on one side (clockwise x side) in the circumferential direction xy has a larger magnetic resistance Rm than the magnetic pole portion 2c-1y on the other side (counterclockwise y side) in the circumferential direction xy.

[0077] In this embodiment, all the magnetic pole pairs 2c-1 to 2c-6 of the six spokes 2b-1 to 2b-6 have the same groove 2ch as the first spoke 2b-1, and the position of the groove 2ch is offset from the center in the circumferential direction xy in either direction (x direction or (or) y direction).

[0078] In the magnetic pole portion pair 2c-2 of the second spoke 2b-2 adjacent to the first spoke 2b-1 on the clockwise x side (one side in the circumferential direction xy), as shown in FIG. Figure 3 As shown in FIG. 1 , the groove portion 2ch is located at a position offset from the center in the circumferential direction xy to the counterclockwise direction y side (the first spoke 2b-1 side). Figure 3 As shown, the cross-sectional area of ​​the magnetic pole portion 2c-2x on the clockwise x side of the magnetic pole portion pair 2c-2 is large, and the cross-sectional area of ​​the magnetic pole portion 2c-2y on the counterclockwise y side is small.

[0079] Therefore, in the magnetic pole pair 2c-2, compared with the case where the groove 2ch is located at the center in the circumferential direction xy, Figure 3 As shown, the magnetic resistance Rm of the magnetic pole portion 2c-2x on the side away from the groove portion 2ch is small (reference symbol L), and the magnetic resistance Rm of the magnetic pole portion 2c-2y on the side close to the groove portion 2ch is large (reference symbol H).

[0080] Therefore, in the second spoke 2b-2, the magnetic pole portion 2c-2y on the other side in the circumferential direction xy (the counterclockwise direction y side) has a larger magnetic resistance Rm than the magnetic pole portion 2c-2x on one side in the circumferential direction xy (the clockwise direction x side).

[0081] Furthermore, in the magnetic pole portion pair 2c-3 of the third spoke 2b-3 adjacent to the second spoke 2b-2 on the clockwise x side (one side in the circumferential direction xy), as shown in FIG. Figure 3 As shown in FIG. 1 , the groove portion 2ch is located at a position offset from the center in the circumferential direction xy to the clockwise x side (the opposite side of the second spoke 2b-2). Figure 3 As shown, the cross-sectional area of ​​the magnetic pole portion 2c-3y on the counterclockwise y side of the magnetic pole portion pair 2c-3 is large. Therefore, the cross-sectional area of ​​the magnetic pole portion 2c-3y is larger than that of the magnetic pole portion 2c-2y on the counterclockwise y side of the magnetic pole portion pair of the second spoke 2b-2.

[0082] Therefore, in the magnetic pole pair 2c-3, compared with the case where the groove 2ch is located at the center in the circumferential direction xy, Figure 3As shown, the magnetic resistance Rm of the magnetic pole portion 2c-3y on the side away from the groove portion 2ch is small (reference numeral L). On the other hand, as described above, in the magnetic pole portion pair 2c-2, the magnetic resistance Rm of the magnetic pole portion 2c-2y on the side close to the groove portion 2ch is large (reference numeral H).

[0083] Therefore, the magnetic pole portion 2c-3y on the other side of the circumferential direction xy (the counterclockwise direction y side) in the magnetic pole portion pair 2c-3 of the third spoke 2b-3 has a smaller magnetic resistance Rm than the magnetic pole portion 2c-2y on the other side of the circumferential direction xy (the counterclockwise direction y side) in the magnetic pole portion pair 2c-2 of the second spoke 2b-2.

[0084] Furthermore, in the magnetic pole portion pair 2c-4 of the fourth spoke 2b-4 located at a point symmetrically with respect to the first spoke 2b-1 about the rotation axis 30, as shown in FIG. Figure 3 As shown in FIG. 1 , the groove portion 2ch is located at a position offset from the center in the circumferential direction xy to the clockwise x side (the opposite side of the third spoke 2b-3). Figure 3 As shown, the cross-sectional area of ​​the magnetic pole portion 2c-4y on the counterclockwise y side of the magnetic pole portion pair 2c-4 is large, and the cross-sectional area of ​​the magnetic pole portion 2c-4x on the clockwise x side is small.

[0085] Therefore, in the magnetic pole pair 2c-4, compared with the case where the groove 2ch is located at the center in the circumferential direction xy, Figure 3 As shown, the magnetic resistance Rm of the magnetic pole portion 2c-4y on the side away from the groove portion 2ch is small (reference symbol L), and the magnetic resistance Rm of the magnetic pole portion 2c-4x on the side close to the groove portion 2ch is large (reference symbol H).

[0086] On the other hand, in the magnetic pole portion pair 2c-5 of the fifth spoke 2b-5 located at a point symmetrically with respect to the second spoke 2b-2 about the rotation axis 30, as shown in FIG. Figure 3 As shown in FIG. 1 , the groove portion 2ch is located at a position offset from the center in the circumferential direction xy to the counterclockwise direction y side (the fourth spoke 2b-4 side). Figure 3 As shown, the cross-sectional area of ​​the magnetic pole portion 2c-5x on the clockwise x side of the magnetic pole portion pair 2c-5 is large, and the cross-sectional area of ​​the magnetic pole portion 2c-5y on the counterclockwise y side is small.

[0087] Therefore, in the magnetic pole pair 2c-5, compared with the case where the groove 2ch is located at the center in the circumferential direction xy, Figure 3 As shown, the magnetic resistance Rm of the magnetic pole portion 2c-5x on the side away from the groove portion 2ch is small (reference symbol L), and the magnetic resistance Rm of the magnetic pole portion 2c-5y on the side close to the groove portion 2ch is large (reference symbol H).

[0088] Furthermore, regarding the sixth spoke 2b-6 located between the first spoke 2b-1 and the fifth spoke 2b-5, as shown in FIG. Figure 3 As shown in FIG. 1 , the groove 2ch is also located at a position deviated from the center in the circumferential direction xy to the clockwise x side (the first spoke 2b-1 side). Therefore, similarly, the cross-sectional area of ​​the magnetic pole portion 2c-6x is small, and the magnetic pole portion 2c-6y is large. Therefore, in the magnetic pole portion pair 2c-6, compared with the case where the groove 2ch is located at the center in the circumferential direction xy, as shown in FIG. Figure 3 As shown, the magnetic resistance Rm of the magnetic pole portion 2c-6y on the side away from the groove portion 2ch is small (reference symbol L), and the magnetic resistance Rm of the magnetic pole portion 2c-6x on the side close to the groove portion 2ch is large (reference symbol H).

[0089] In this embodiment, in all the magnetic pole pairs 2c-1 to 2c-6 of the six spokes 2b-1 to 2b-6, the magnetic poles 2c-1x to 2c-6x and the magnetic poles 2c-1y to 2c-6y have different magnetic resistances Rm, so that the magnetic balance in the circumferential direction xy is destroyed, thereby increasing the cogging torque.

[0090] Hereinafter, the mechanism of increasing the cogging torque based on the configuration of this embodiment will be described. However, the mechanism in the following description is modeled for the purpose of explanation and partly includes an estimated mechanism, and therefore, the mechanism that actually occurs is not guaranteed.

[0091] Figure 4 2 shows a cross-sectional view (transverse cross-sectional view) of a motor of a conventional example taken along a plane perpendicular to the axis. Figure 4 This is a diagram for explaining the mechanism of generation of cogging torque in a conventional motor.

[0092] The motor 101 of the conventional example has the same configuration as the motor 1 of the first embodiment except that the shape of the rotor core 102 of the rotor 120 is different. Figure 4 In the drawings, the same reference numerals are given to the components having the same configuration as those in the first embodiment.

[0093] In the rotor core 102 of the conventional example, the magnetic pole pair 102c at the end of the spoke 102b in the outer direction m is also provided with a groove 102ch extending parallel to the axial direction of the rotating shaft 30 on the surface facing the magnet 11. Figure 4 As shown, the groove portion 102ch is located at the center in the circumferential direction xy among the pair of magnetic pole portions 102cx and 102cy included in all the spokes 102b.

[0094] Therefore, if Figure 4As shown, the cross-sectional areas of the cross sections of the magnetic pole portion 102cx on the clockwise x side and the magnetic pole portion 102cy on the counterclockwise y side of the pair of magnetic pole portions 102cx and 102cy are equal. Therefore, in the spoke 102b, the magnetic resistance Rm of the magnetic pole portion 102cx on one side of the circumferential xy direction (clockwise x side) and the magnetic pole portion 102cy on the other side of the circumferential xy direction (counterclockwise y side) are substantially equal.

[0095] exist Figure 4 In the diagram, the force in the direction of the cogging torque is schematically recorded by a hollow arrow, and the force in the direction of the cogging torque is schematically recorded by a hatched arrow with a slash (described later). Figure 5 The magnetic resistance Rm of the magnetic pole portion 102cx and the magnetic pole portion 102cy are substantially equal, and therefore, a state of circumferential magnetic balance is achieved. That is, the force that becomes the cogging torque and the force in the direction of canceling the cogging torque are generated in opposite directions, respectively, and therefore, the force that becomes the cogging torque is canceled, and in the motor 101 of the conventional example, the cogging torque is small.

[0096] Figure 5 is with Figure 1 The cross-sectional view (transverse cross-sectional view) of the motor of the same first embodiment taken along a plane perpendicular to the axis is a diagram for explaining the mechanism of generating the cogging torque. As described above, in the present embodiment, in all the magnetic pole pairs 2c-1 to 2c-6 possessed by the six spokes 2b-1 to 2b-6, the magnetic resistance Rm of the magnetic poles 2c-1x to 2c-6x on one side of the circumferential direction xy (the x side in the clockwise direction) and the magnetic resistance Rm of the magnetic poles 2c-1y to 2c-6y on the other side of the circumferential direction xy (the y side in the counterclockwise direction) are different from each other.

[0097] Therefore, the magnetic balance in the circumferential direction is destroyed. That is, in the portion where the magnetic resistance Rm is small and the magnetic flux easily passes through, the force (the arrow with shadow) that cancels the cogging torque is directed in the radial direction. Therefore, it is estimated that the force that cancels the cogging torque is small, and the force that cancels the cogging torque is not canceled. In the motor 1 of this embodiment, the cogging torque can be increased.

[0098] In the present embodiment, in all the magnetic pole pairs 2c-1 to 2c-6 of the six spokes 2b-1 to 2b-6, the magnetic poles 2c-1x to 2c-6x and the magnetic poles 2c-1y to 2c-6y have different magnetic resistances Rm, but if the magnetic resistances Rm of a pair of magnetic poles in at least one of the six spokes 2b-1 to 2b-6 are different, the magnetic balance in the circumferential direction is destroyed, and thus the cogging torque can be increased. However, in the present embodiment, it is particularly preferred to have conditions (conditions A, B, and C) for further increasing the cogging torque as shown below.

[0099] In this embodiment, the magnetic pole portion 2c-2y on the other side of the circumferential direction xy (the counterclockwise direction y side) of the magnetic pole portion pair 2c-2 of the second spoke 2b-2 has a larger magnetic resistance Rm than the magnetic pole portion 2c-2x on one side of the circumferential direction xy (the clockwise direction x side). Figure 3 As shown, the narrow groove 1S between the first spoke 2b-1 and the second spoke 2b-2 12 In the state where the magnetic pole portion 2c-1x and the magnetic pole portion 2c-2y are close to each other (H in the figure), the magnetic resistance Rm is large. Therefore, in the circumferential direction xy, the parts with large magnetic resistance Rm are concentrated, and the magnetic balance is destroyed in a larger manner.

[0100] In this way, in at least one slot, the magnetic pole portions having large magnetic resistances Rm are in a state close to each other (condition A), whereby the cogging torque can be further increased.

[0101] The cogging torque increasing effect based on condition A is not limited to the case where the number of spokes of the rotor core is six, that is, the case of the present embodiment. Regardless of the number of spokes, the cogging torque increasing effect can be achieved as long as condition A is satisfied.

[0102] In addition, in the present embodiment, the magnetic pole portion 2c-3y on the other side of the circumferential direction xy (the counterclockwise direction y side) in the magnetic pole portion pair 2c-3 of the third spoke 2b-3 adjacent to the second spoke 2b-2 on one side of the circumferential direction xy (the clockwise direction x side) has a smaller magnetic resistance Rm than the magnetic pole portion 2c-2y on the other side of the circumferential direction xy (the counterclockwise direction y side) in the magnetic pole portion pair of the second spoke 2b-2.

[0103] Therefore, if Figure 3 As shown, the narrow groove 1S between the second spoke 2b-2 and the third spoke 2b-3 23 In the embodiment, the magnetic pole portion 2c-2x and the magnetic pole portion 2c-3y are close to each other in the state where the magnetic resistance Rm is small. That is, the slot 1S between the first spoke 2b-1 and the second spoke 2b-2 is close to the magnetic pole portion 2c-1x and the magnetic pole portion 2c-2y in the state where the magnetic resistance Rm is large. 12 The adjacent slot 1S 23 In the figure, the magnetic pole portion 2c-2x and the magnetic pole portion 2c-3y are close to each other, and the magnetic resistance Rm is small. Therefore, in the circumferential direction xy, the part with large magnetic resistance Rm is close to the part with small magnetic resistance Rm, and the magnetic balance is destroyed in a larger way.

[0104] Like this, two slits 1S are continuous in the circumferential direction. 12 , 1S 23 In the slots 1S, each of which is located on one side 12 The magnetic poles with large magnetic resistance Rm (H) are close to each other, and the slot 1S on the other side is 23In a state where the magnetic pole portions where the magnetic resistance Rm is small (reference symbol L) are close to each other, the portion with large magnetic resistance Rm is brought close to the portion with small magnetic resistance Rm (condition B), thereby further increasing the cogging torque.

[0105] The cogging torque increasing effect based on the condition B is not limited to the case where the number of spokes of the rotor core is six, that is, the case of the present embodiment. Regardless of the number of spokes, the cogging torque increasing effect can be achieved in the same manner as long as the condition B is satisfied.

[0106] Moreover, in the present embodiment, the number of spokes of the rotor core 2 is an even number, and in the magnetic pole portion pair 2c-4 of the fourth spoke 2b-4 located at a point-symmetrical position with respect to the first spoke 2b-1 with respect to the rotating shaft 30 as the center, the magnetic resistance Rm of the magnetic pole portion 2c-4y is small (reference numeral L), and the magnetic resistance Rm of the magnetic pole portion 2c-4x is large (reference numeral H).

[0107] On the other hand, in the magnetic pole portion pair 2c-5 of the fifth spoke 2b-5 located at a point-symmetrical position with respect to the second spoke 2b-2 and centered on the rotation axis 30, the magnetic resistance Rm of the magnetic pole portion 2c-5x is small (reference numeral L), and the magnetic resistance Rm of the magnetic pole portion 2c-5y is large (reference numeral H).

[0108] Therefore, if Figure 3 As shown, in the narrow groove 1S between the first spoke 2b-1 and the second spoke 2b-2 12 The slot 1S is located between the fourth spoke 2b-4 and the fifth spoke 2b-5 at a point symmetrical to the rotation axis 30. 45 In the state where the magnetic pole portion 2c-4x and the magnetic pole portion 2c-5y are close to each other and both have large magnetic resistance Rm (reference numeral H).

[0109] As described above, the slot 1S between the first spoke 2b-1 and the second spoke 2b-2 12 In the embodiment, the magnetic pole portion 2c-1x and the magnetic pole portion 2c-2y are close to each other (H in the figure) in which the magnetic resistance Rm is large. Therefore, in the circumferential direction xy, the slots in the state where the magnetic pole portions with large magnetic resistance Rm are close to each other are located at point symmetric positions.

[0110] As described above, in the present embodiment, the slots are located at point-symmetrical positions in a state where the magnetic pole portions having large magnetic resistance Rm are close to each other (condition C), thereby increasing the cogging torque in a coordinated manner.

[0111] The cogging torque increasing effect based on the condition C is not limited to the case where the number of spokes of the rotor core is six, that is, the case of the present embodiment, but the same increasing effect can be achieved as long as the number of spokes is an even number and the condition C is satisfied.

[0112] [Second Embodiment]

[0113] Next, a motor according to a second embodiment of the present invention will be described with reference to the drawings. The motor according to the second embodiment has the same configuration as the motor 1 according to the first embodiment except that the shape of the rotor core is different.

[0114] Therefore, in the present embodiment, a cross-sectional view of only the rotor core (core) 22 and the rotating shaft 30 is used. Figure 6 In addition, for other configurations and overall configuration of the motor of this embodiment, refer to Figure 1 and Figure 2 .

[0115] In this embodiment, only the magnetic pole portions ( Figure 6 The shapes of the reference numerals 22c-3 and 22c-6 in the figure are different, and the other shapes and structures are the same as those of the rotor core 2 in the first embodiment. Figure 6 In the present invention, the same reference numerals are given to the components having the same configuration as those in the first embodiment, and detailed description thereof will be omitted.

[0116] In this embodiment, in the magnetic pole portion pair 22c-3 of the third spoke 22b-3 adjacent to the second spoke 2b-2 on the clockwise x side (one side in the circumferential direction xy), as shown in FIG. Figure 6 In addition, in the magnetic pole pair 22c-6 of the sixth spoke 22b-6 located at a point symmetrically about the rotation axis 30 with respect to the third spoke 22b-3, the groove 2ch is located at the center of the circumferential direction xy like the magnetic pole pair 22c-3.

[0117] That is, in the present embodiment, in the magnetic pole pair 22c-3 and the sixth spoke 22b-6 located at a point symmetrically with respect to the third spoke 22b-3 about the rotation axis 30, the position of the groove 2ch is not biased in the circumferential direction xy. Figure 6 As shown, the cross-sectional areas of the cross sections of the pair of magnetic pole portions 22c-3x, 22c-3y and the pair of magnetic pole portions 22c-6x, 22c-6y in the magnetic pole portion pair 22c-3 and the magnetic pole portion pair 22c-6 are substantially equal to each other.

[0118] Therefore, in the magnetic pole pair 22c-3, the magnetic resistance Rm of the magnetic pole 22c-3x and the magnetic pole 22c-3y are substantially equal to each other. This magnetic resistance Rm is smaller (lower) than the case marked with the reference numeral H, and larger (higher) than the case marked with the reference numeral L. The magnetic resistance Rm of the magnetic pole portion when the position of the groove portion 2ch is not biased in the circumferential direction xy is called "medium". Figure 6 In the figure, it is indicated by the figure symbol "M" (hereinafter, the same applies to other embodiments and drawings).

[0119] In the present embodiment, regarding the magnetic pole pair 2c-0 of four spokes 2b-0 (fill in 0 with any number of 1, 2, 4, and 5. The same applies to the present embodiment below) among the six spokes 2b-1 to 22b-6, the magnetic resistance Rm of the magnetic pole 2c-0x on one side of the circumferential xy (clockwise x side) and the magnetic resistance Rm of the magnetic pole 2c-0y on the other side of the circumferential xy (counterclockwise y side) are different. Therefore, in the present embodiment, the magnetic balance in the circumferential direction is destroyed, and the cogging torque is increased.

[0120] In addition, in this embodiment, the magnetic pole portion 2c-2y on the other side of the circumferential direction xy (the counterclockwise direction y side) in the magnetic pole portion pair 2c-2 of the second spoke 2b-2 has a larger magnetic resistance Rm than the magnetic pole portion 2c-2x on one side of the circumferential direction xy (the clockwise direction x side).

[0121] Therefore, if Figure 6 As shown, the narrow groove 2S between the first spoke 2b-1 and the second spoke 2b-2 12 In the embodiment, the magnetic pole portion 2c-1x and the magnetic pole portion 2c-2y are close to each other (reference numeral H) in which the magnetic resistance Rm is large. In this way, in at least one slot, the magnetic pole portions in which the magnetic resistance Rm is large are close to each other (condition A), thereby further increasing the cogging torque.

[0122] In addition, in the present embodiment, the magnetic resistance Rm (reference numeral M) of the magnetic pole portion 22c-3y on the other side of the circumferential direction xy (the counterclockwise direction y side) in the magnetic pole portion pair 22c-3 of the third spoke 22b-3 adjacent to the second spoke 2b-2 on one side of the circumferential direction xy (the clockwise direction x side) is smaller than the magnetic resistance Rm (reference numeral H) of the magnetic pole portion 2c-2y on the other side of the circumferential direction xy (the counterclockwise direction y side) in the magnetic pole portion pair of the second spoke 2b-2.

[0123] Therefore, if Figure 6 As shown, the narrow groove 2S between the second spoke 2b-2 and the third spoke 22b-3 23In the embodiment, the magnetic pole portion 2c-2x with small magnetic resistance Rm is close to the magnetic pole portion 2c-3y with medium magnetic resistance Rm. That is, the slot 2S between the first spoke 2b-1 and the second spoke 2b-2 is close to the magnetic pole portion 2c-1x and the magnetic pole portion 2c-2y with large magnetic resistance Rm. 12 The adjacent slot 2S 23 In contrast, the magnetic pole portion 2c-2x with relatively small magnetic resistance Rm is close to the magnetic pole portion 22c-3y. Therefore, in the circumferential direction xy, the portion with large magnetic resistance Rm is close to the portion with small magnetic resistance Rm, and the magnetic balance is more likely to be destroyed.

[0124] Like this, two slits 2S continuous in the circumferential direction 12 , 2S 23 In the slot 2S, each of which is located on one side 12 The magnetic poles with large magnetic resistance Rm (H) are close to each other, and the slot 2S on the other side is 23 The magnetic pole portion having a small magnetic resistance Rm (reference symbol L) and the magnetic pole portion having a medium magnetic resistance Rm (reference symbol M) are close to each other (condition B), thereby further increasing the cogging torque.

[0125] Moreover, in the present embodiment, the number of spokes of the rotor core 22 is an even number, and in the magnetic pole portion pair 2c-4 of the fourth spoke 2b-4 located at a point-symmetrical position with respect to the first spoke 2b-1 with respect to the rotating shaft 30 as the center, the magnetic resistance Rm of the magnetic pole portion 2c-4y is small (reference numeral L), and the magnetic resistance Rm of the magnetic pole portion 2c-4x is large (reference numeral H).

[0126] On the other hand, in the magnetic pole portion pair 2c-5 of the fifth spoke 2b-5 located at a point-symmetrical position with respect to the second spoke 2b-2 and centered on the rotation axis 30, the magnetic resistance Rm of the magnetic pole portion 2c-5x is small (reference numeral L), and the magnetic resistance Rm of the magnetic pole portion 2c-5y is large (reference numeral H).

[0127] Therefore, if Figure 6 As shown, in the slot 2S between the first spoke 2b-1 and the second spoke 2b-2 12 The slot 2S between the fourth spoke 2b-4 and the fifth spoke 2b-5 is located at a point symmetrical to the rotation axis 30. 45 In the state where the magnetic pole portion 2c-4x and the magnetic pole portion 2c-5y, both of which have large magnetic resistance Rm, are close to each other.

[0128] As described above, the slot 2S between the first spoke 2b-1 and the second spoke 2b-2 12In the state where the magnetic pole portion 2c-1x and the magnetic pole portion 2c-2y are both in a state where the magnetic resistance Rm is large, they are close to each other. Therefore, in the circumferential direction xy, the slots in a state where the magnetic pole portions with large magnetic resistance Rm are close to each other are located at point-symmetrical positions.

[0129] As described above, in the present embodiment, the slots in a state where the magnetic pole portions having large magnetic resistance Rm are close to each other are located at point-symmetrical positions (condition C), thereby synergistically increasing the cogging torque.

[0130] [Third Embodiment]

[0131] Next, a motor according to a third embodiment as an example of the present invention will be described with reference to the drawings. The motor according to the third embodiment has the same configuration as the motor 1 according to the first embodiment except that the shape of the rotor core is different.

[0132] Therefore, in the present embodiment, a cross-sectional view showing only the rotor core (core) 32 and the rotating shaft 30 is used. Figure 7 In addition, for other configurations and overall configuration of the motor of this embodiment, refer to Figure 1 and Figure 2 .

[0133] like Figure 7 As shown, the magnetic pole pair 32c-1 to 32c-6 is not provided with a shape like the groove 2ch in the first embodiment. In this embodiment, the position of the crimping portion 32d is offset in the circumferential direction xy to replace the groove. Here, the "crimping portion" refers to a recessed portion that is pressed from the thickness direction (axial direction of the rotating shaft) of the rotor core in order to fix and integrate the rotor core composed of a stack of silicon steel sheets and the like.

[0134] The pressure-contacting portion 32d is provided on the magnetic pole portion pairs 32c-1 to 32c-6 in each of the spokes 32b-1 to 32b-6 and their vicinities.

[0135] When the pressure-bonding portion 32d is provided on the rotor core 32, the magnetic flux is formed so as to avoid the portion of the pressure-bonding portion. Therefore, the magnetic resistance Rm of the region where the pressure-bonding portion 32d is provided and its vicinity tends to be large.

[0136] In this embodiment, if Figure 7 As shown, the positions of the crimping portions 32d provided on the first spoke 32b-1 and the fourth spoke 32b-4 located at a point symmetrically with respect to the first spoke 32b-1 about the rotation shaft 30 are offset to the clockwise x side of the circumferential direction xy. The positions of the crimping portions 32d provided on the first spoke 32b-1 and the fourth spoke 32b-4 are made to be point symmetrically with respect to the rotation shaft 30.

[0137] In addition, if Figure 7As shown, the positions of the crimping portions 32d provided on the second spoke 32b-2 and the fifth spoke 32b-5 located at a point symmetrically with respect to the second spoke 32b-2 about the rotation axis 30 are offset to the counterclockwise direction y side of the circumferential direction xy. The positions of the crimping portions 32d provided on the second spoke 32b-2 and the fifth spoke 32b-5 are made to be point symmetrically with respect to the rotation axis 30.

[0138] It should be noted that if Figure 7 As shown, the position of the crimping portion 32d provided on the third spoke 32b-3 and the sixth spoke 32b-6 provided at a point symmetrically located relative to the third spoke 32b-3 with the rotation shaft 30 as the center is the center of the circumferential xy direction of the third spoke 32b-3 and the sixth spoke 32b-6, and is not biased.

[0139] A line segment connecting the positions of the pressure-bonding portion 32d provided in the first spoke 32b-1 and the fourth spoke 32b-4 is defined as a line segment L. 14 The line segment connecting the positions of the crimping portion 32d provided at the second spoke 32b-2 and the fifth spoke 32b-5 is defined as line segment L. 25 The line segment connecting the positions of the crimping portion 32d provided at the third spoke 32b-3 and the sixth spoke 32b-6 is defined as the line segment L. 36 .

[0140] In this way, line segment L 36 With line segment L 14 The angle α(°), line segment L 14 With line segment L 25 The angle β(°) and the line segment L 25 With line segment L 36 The relationship of the formed angle γ (°) is expressed by the following equation (2).

[0141] β<α≒γ···Formula (2)

[0142] In the first spoke 32b-1, near the magnetic pole pair 32c-1, the magnetic pole 32c-1x on one side (clockwise x side) has a narrow area through which the magnetic flux easily passes, and has a large magnetic resistance Rm (reference numeral H) due to the influence of the crimping portion 32d located at a position biased toward the clockwise x side of the circumferential direction xy. On the contrary, the magnetic pole 32c-1y on the other side (counterclockwise y side) is not greatly affected by the crimping portion 32d, and therefore has a wide area through which the magnetic flux easily passes, and has a small magnetic resistance Rm (reference numeral L). The fourth spoke 32b-4 located at a point-symmetrical position with respect to the rotating shaft 30 as the center is also the same as the first spoke 32b-1, and has a large magnetic resistance Rm (reference numeral H) for the magnetic pole 32c-4x, and a small magnetic resistance Rm (reference numeral L) for the magnetic pole 32c-1y.

[0143] In the second spoke 32b-2, near the magnetic pole pair 32c-2, the magnetic pole 32c-2y on the other side (the counterclockwise y side) has a narrow area through which the magnetic flux can easily pass, and has a large magnetic resistance Rm (reference numeral H) due to the influence of the crimping portion 32d located at a position offset from the circumferential direction xy in the counterclockwise direction y side. On the contrary, the magnetic pole 32c-2x on one side (the clockwise x side) is not much affected by the crimping portion 32d, and therefore has a wide area through which the magnetic flux can easily pass, and has a small magnetic resistance Rm (reference numeral L). On the other hand, the fifth spoke 32b-5 located at a point-symmetrical position with respect to the rotating shaft 30 as the center is also the same as the second spoke 32b-2, and the magnetic pole 32c-5y has a large magnetic resistance Rm (reference numeral H), and the magnetic pole 32c-5x has a small magnetic resistance Rm (reference numeral L).

[0144] In the third spoke 32b-3, near the magnetic pole pair 32c-3, the influence of the crimping portion 32d located at the center of the circumferential direction xy and not biased is roughly equal on one side (clockwise direction x side) and the other side (counterclockwise direction y side) in the circumferential direction xy. Therefore, the magnetic resistance Rm of the magnetic pole portion 32c-3x and the magnetic pole portion 32c-3y are both medium (reference numeral M). The sixth spoke 32b-6 located at a point-symmetrical position with respect to the rotation axis 30 as the center is also the same as the third spoke 32b-3, and the magnetic resistance Rm of the magnetic pole portion 32c-6x and the magnetic pole portion 32c-6y are both medium (reference numeral M).

[0145] In the present embodiment, regarding the magnetic pole pair 32c-0 of four spokes 32b-0 (0 is filled with any number of 1, 2, 4 and 5. The same applies to the present embodiment below) among the six spokes 32b-1 to 32b-6, the magnetic resistance Rm of the magnetic pole 32c-0x on one side of the circumferential direction xy (clockwise direction x side) and the magnetic resistance Rm of the magnetic pole 32c-0y on the other side of the circumferential direction xy (counterclockwise direction y side) are different. Therefore, in the present embodiment, the magnetic balance in the circumferential direction is destroyed, and the increase of the cogging torque is achieved.

[0146] In addition, in this embodiment, the magnetic pole portion 32c-2y on the other side of the circumferential direction xy (the counterclockwise direction y side) in the magnetic pole portion pair 32c-2 of the second spoke 32b-2 has a larger magnetic resistance Rm than the magnetic pole portion 32c-2x on one side of the circumferential direction xy (the clockwise direction x side).

[0147] Therefore, if Figure 7 As shown, the slot 3S between the first spoke 32b-1 and the second spoke 32b-2 12In the embodiment, the magnetic pole portion 32c-1x and the magnetic pole portion 32c-2y are in a state where the magnetic resistance Rm is large (reference numeral H) and they are close to each other. In this way, in at least one slot, the magnetic pole portions with large magnetic resistance Rm are close to each other (condition A), thereby further increasing the cogging torque.

[0148] In addition, in the present embodiment, the magnetic resistance Rm (reference numeral M) of the magnetic pole portion 32c-3y on the other side of the circumferential direction xy (the counterclockwise direction y side) in the magnetic pole portion pair 32c-3 of the third spoke 32b-3 adjacent to the second spoke 32b-2 on one side of the circumferential direction xy (the clockwise direction x side) is smaller than the magnetic resistance Rm (reference numeral H) of the magnetic pole portion 32c-2y on the other side of the circumferential direction xy (the counterclockwise direction y side) in the magnetic pole portion pair 32c-2 of the second spoke 32b-2.

[0149] Therefore, if Figure 7 As shown, the slot 3S between the second spoke 32b-2 and the third spoke 32b-3 23 In the embodiment, the magnetic pole portion 32c-2x with small magnetic resistance Rm is close to the magnetic pole portion 32c-3y with medium magnetic resistance Rm. That is, the slot 3S between the first spoke 32b-1 and the second spoke 32b-2 is close to the magnetic pole portion 32c-1x and the magnetic pole portion 32c-2y with large magnetic resistance Rm. 12 The adjacent slot 3S 23 In contrast, the magnetic pole portion 32c-2x and the magnetic pole portion 32c-3y with relatively small magnetic resistance Rm are close to each other. Therefore, in the circumferential direction xy, the portion with large magnetic resistance Rm and the portion with small magnetic resistance Rm are close to each other, and the magnetic balance is more likely to be destroyed.

[0150] Like this, two slits 3S are continuous in the circumferential direction. 12 、3S 23 In the slots 3S, each of which is located on one side 12 The magnetic poles with large magnetic resistance Rm (H) are close to each other, and the slot 3S on the other side is 23 The magnetic pole portion having a small magnetic resistance Rm (reference symbol L) and the magnetic pole portion having a medium magnetic resistance Rm (reference symbol M) are close to each other (condition B), thereby further increasing the cogging torque.

[0151] Moreover, in the present embodiment, the number of spokes of the rotor core 32 is an even number, and in the magnetic pole portion pair 32c-4 of the fourth spoke 32b-4 located at a point-symmetrical position with respect to the first spoke 32b-1 with respect to the rotating shaft 30 as the center, the magnetic resistance Rm of the magnetic pole portion 32c-4y is small (reference numeral L), and the magnetic resistance Rm of the magnetic pole portion 32c-4x is large (reference numeral H).

[0152] On the other hand, in the magnetic pole portion pair 32c-5 of the fifth spoke 32b-5 located at a point-symmetrical position with respect to the second spoke 32b-2 and centered on the rotating shaft 30, the magnetic resistance Rm of the magnetic pole portion 32c-5x is small (reference numeral L), and the magnetic resistance Rm of the magnetic pole portion 32c-5y is large (reference numeral H).

[0153] Therefore, if Figure 7 As shown, in the slot 3S between the first spoke 32b-1 and the second spoke 32b-2, 12 The slot 3S is located between the fourth spoke 32b-4 and the fifth spoke 32b-5 at a point symmetrical to the rotation axis 30. 45 In the state where the magnetic pole portion 32c-4x and the magnetic pole portion 32c-5y, both of which have large magnetic resistance Rm, are close to each other.

[0154] As described above, the slot 3S between the first spoke 32b-1 and the second spoke 32b-2 12 In the embodiment, the magnetic pole portion 32c-1x and the magnetic pole portion 32c-2y, both of which have large magnetic resistance Rm, are close to each other. Therefore, in the circumferential direction xy, the slots in which the magnetic pole portions with large magnetic resistance Rm are close to each other are located at point-symmetrical positions.

[0155] As described above, in the present embodiment, the slots in a state where the magnetic pole portions having large magnetic resistance Rm are close to each other are located at point-symmetrical positions (condition C), thereby synergistically increasing the cogging torque.

[0156] [Fourth Embodiment]

[0157] Next, a motor according to a fourth embodiment of the present invention will be described with reference to the drawings. The motor according to the fourth embodiment is similar in structure to the motor 1 according to the first embodiment except that the shape of the rotor core is different. Therefore, in this embodiment, a cross-sectional view showing only the rotor core (core) 42 and the rotating shaft 30 is used. Figure 8 Provide explanation.

[0158] However, in this embodiment, the number of spokes of the rotor core is different from that of the motor 1 of the first embodiment, and accordingly, the magnets, the circuit structure of the control substrate, etc. are different from those of the motor 1 of the first embodiment. These differences are hardly noticeable in appearance, and since they are not characteristic structures of the present invention and this embodiment, for other structures and the overall structure of the motor of this embodiment, refer to Figure 1 and Figure 2 This also applies to the following embodiments.

[0159] Furthermore, in the present embodiment, the magnetic resistance Rm of a pair of magnetic pole portions of each spoke is adjusted by utilizing the circumferential xy deviation of the groove portion provided on the surface opposite to the magnet 11 in the center of the magnetic pole portion, as in the first and second embodiments. Since the same principle is utilized, repeated descriptions are avoided in the present embodiment, and the circumferential xy deviation of the groove portion is not touched upon. Only the magnitude of the magnetic resistance Rm of the magnetic pole portion as a result thereof (large (reference numeral H), small (reference numeral L), medium (reference numeral M)) is discussed. This is also the same in subsequent embodiments. Of course, the magnetic resistance Rm of a pair of magnetic pole portions may be adjusted by any method such as the method of deviating the position of the crimping portion in the circumferential xy described in the third embodiment. This is also the same in subsequent embodiments.

[0160] In the present embodiment, the rotor core 42 has: an annular portion 42a, surrounding the rotating shaft 30; and five spokes 42b-1 to 42b-5, extending radially (radially) from the annular portion 42a with the rotating shaft 30 as the axis. The rotor core 42 has a pair of magnetic pole portions (magnetic pole portion pairs 42c-1 to 42c-5) extending in two directions in the circumferential direction xy at the ends of the radial directions mn (especially, the outer direction m) of each of the odd-numbered (five) spokes 42b-1 to 42b-5. It should be noted that the rotor coils (coils) are respectively wound around the five spokes 42b-1 to 42b-5, but in Figure 8 This is omitted in the illustration of the fifth embodiment. Fig. 9 The same is true in Chinese.

[0161] First, in Figure 8 In the figure, the spoke on the counterclockwise direction y side of the two spokes extending from the annular portion 42a in the downward direction d is set as the first spoke 42b-1, and the second spoke 42b-2, the third a spoke 42b-3, the fourth a spoke 42b-4 and the fifth a spoke 42b-5 are set in the clockwise direction x from the first spoke 42b-1.

[0162] In this embodiment, in the first spoke 42b-1, the magnetic resistance Rm (reference numeral H) of the magnetic pole portion 42c-1x on one side of the circumferential direction xy (clockwise direction x side) is larger than the magnetic resistance Rm (reference numeral L) of the magnetic pole portion 42c-1y on the other side of the circumferential direction xy (counterclockwise direction y side).

[0163] In addition, in the second spoke 42b-2, the magnetic resistance Rm (reference numeral H) of the magnetic pole portion 42c-2y on the other side of the circumferential direction xy (the counterclockwise direction y side) is larger than the magnetic resistance Rm (reference numeral L) of the magnetic pole portion 42c-2x on one side of the circumferential direction xy (the clockwise direction x side).

[0164] In addition, in the third a-spoke 42b-3, the magnetic resistance Rm (reference numeral H) of the magnetic pole portion 42c-3y on the other side of the circumferential direction xy (the counterclockwise direction y side) is larger than the magnetic resistance Rm (reference numeral L) of the magnetic pole portion 42c-3x on one side of the circumferential direction xy (the clockwise direction x side).

[0165] In addition, in the fifth a-spoke 42b-5, the magnetic resistance Rm (reference numeral H) of the magnetic pole portion 42c-5x on one side of the circumferential direction xy (clockwise direction x side) is larger than the magnetic resistance Rm (reference numeral L) of the magnetic pole portion 42c-5y on the other side of the circumferential direction xy (counterclockwise direction y side).

[0166] On the other hand, in the magnetic pole pair 42c-4 of the fourth a-spoke 42b-4, the magnetic resistance Rm of the magnetic poles 42c-4x and 42c-4y on one side (clockwise x side) and the other side (counterclockwise y side) of the circumferential direction xy is approximately equal (reference numeral M).

[0167] In this embodiment, if Figure 8 As shown, regarding the magnetic pole pair 42c-0 of four spokes 42b-0 (0 is filled with any number of 1, 2, 3 and 5. The same applies to the present embodiment below) among the five spokes 42b-1 to 42b-5, the magnetic resistance Rm of the magnetic pole 42c-0x on one side of the circumferential xy (clockwise x side) and the magnetic resistance Rm of the magnetic pole 42c-0y on the other side of the circumferential xy (counterclockwise y side) are different. Therefore, in the present embodiment, the magnetic balance in the circumferential direction is destroyed, and the increase of the cogging torque is achieved.

[0168] In addition, in this embodiment, if Figure 8 As shown, the slot 4S between the first spoke 42b-1 and the second spoke 42b-2 12 In the embodiment, the magnetic pole portion 42c-1x and the magnetic pole portion 42c-2y are close to each other (reference numeral H) in which the magnetic resistance Rm is large. In this way, in at least one slot, the magnetic pole portions in which the magnetic resistance Rm is large are close to each other (condition A), thereby further increasing the cogging torque.

[0169] In the present embodiment, the number of spokes of the rotor core is an odd number, and therefore, condition C described in the first embodiment is not satisfied. However, in the present embodiment, as shown below, a condition (condition D) unique to the case where the number of spokes is an odd number, which further increases the tooth torque, is preferred.

[0170] First, in this embodiment, with respect to the slot 4S between the first spoke 42b-1 and the second spoke 42b-2 12The magnetic resistances of the two magnetic pole portions 42c-4x and 42c-4y of the magnetic pole portion pair 42c-4 of the fourth a-spoke 42b-4 located at a point symmetrical position about the rotation shaft 30 are substantially equal (condition D-1).

[0171] In addition, in the present embodiment, the magnetic resistance Rm (reference numeral L) of at least one of the magnetic pole portion 42c-3x on the circumferential side of the fourth a spoke 42b-4 in the magnetic pole portion pair 42c-3 of the third a spoke 42b-3 and the magnetic pole portion 42c-5y on the circumferential side of the fourth a spoke 42b-4 in the magnetic pole portion pair 42c-5 of the fifth a spoke 42b-5 is smaller than the magnetic resistance Rm (reference numeral M for both 42c-4x and 42c-4y) of one of the magnetic pole portions in the magnetic pole portion pair 42c-4 of the fourth a spoke 42b-4 (condition D-2).

[0172] The above conditions D-1 and D-2 are satisfied as condition D, and in the present embodiment, condition D is satisfied. It should be noted that in condition D-2, the scheme of the present embodiment in which both the magnetic pole portion 42c-3x and the magnetic pole portion 42c-5y have a smaller magnetic resistance Rm than the magnetic pole portion 42c-4x (≒42c-4y) is particularly preferred.

[0173] As described above, in the present embodiment, the slots 4S are located in a state where the magnetic pole portions having a large magnetic resistance Rm are close to each other. 12 By setting the magnetic resistance Rm to be small on at least one side of the spokes at the point-symmetric position, it is estimated that the manner in which the magnetic balance is destroyed in the circumferential direction xy further increases, and therefore the cogging torque further increases.

[0174] [Fifth Embodiment]

[0175] Next, a motor according to a fifth embodiment of the present invention will be described with reference to the drawings. The motor according to the fifth embodiment is similar in structure to the motor 1 according to the first embodiment except that the shape of the rotor core is different. Therefore, in this embodiment, a cross-sectional view showing only the rotor core (core) 52 and the rotating shaft 30 is used. Fig. 9 Provide explanation.

[0176] The rotor core 52 in this embodiment corresponds to only the magnetic pole pair 42c-4 of the fourth spoke 42b-4 among the five spokes 42b-1 to 42b-5 in the fourth embodiment ( Fig. 9 The shape of the rotor core 42 is different from that of the reference numeral 52c-4 in the figure, and the other shapes and structures are the same as those of the rotor core 42 in the fourth embodiment. Fig. 9In the present invention, the same reference numerals are given to components having the same configuration as those in the fourth embodiment, and detailed description thereof is omitted.

[0177] It should be noted that the third b-spoke 52b-3 and the fifth b-spoke 52b-5 in this embodiment are the same as the third a-spoke 42b-3 and the fifth a-spoke 42b-5 in the fourth embodiment, but for ease of description, unique reference numerals (52b-3 and 52b-5) are marked in this embodiment. The components (magnetic pole portion, magnetic pole portion pair, etc.) related to the third b-spoke 52b-3 and the fifth b-spoke 52b-5 are also the same.

[0178] In this embodiment, in the magnetic pole portion pair 52c-4 of the fourth b-spoke 52b-4, the magnetic resistance Rm (reference numeral H) of the magnetic pole portion 52c-4x on one side of the circumferential direction xy (clockwise direction x side) is larger than the magnetic resistance Rm (reference numeral L) of the magnetic pole portion 52c-4y on the other side of the circumferential direction xy (counterclockwise direction y side).

[0179] That is, in the magnetic pole portion pair 42c-4 of the fourth a-spoke 42b-4 in the fourth embodiment, the magnetic resistance Rm of the magnetic pole portions 42c-4x and 42c-4y on one side (clockwise x side) and the other side (counterclockwise y side) of the circumferential direction xy are approximately equal (figure mark M). In contrast, in the present embodiment, the magnetic resistance Rm of the magnetic pole portions 52c-4x and 52c-4y are different from each other.

[0180] In the present embodiment, for all the magnetic pole pairs 42c-Δ and 52c-□ possessed by the five spokes 42b-Δ (Δ is filled with 1 or 2. The same also applies to the present embodiment below) and 52b-□ (□ is filled with any number from 3 to 5. The same also applies to the present embodiment below), the magnetic resistance Rm of the magnetic pole 42c-Δx and 52c-□x on one side of the circumferential direction xy (the x side in the clockwise direction) is different from the magnetic resistance Rm of the magnetic pole 42c-Δy and 52c-□y on the other side of the circumferential direction xy (the y side in the counterclockwise direction). Therefore, in the present embodiment, the aspect of achieving an increase in the cogging torque while being in a state where the circumferential magnetic balance is destroyed is the same as in the fourth embodiment.

[0181] In addition, the narrow groove 4S between the first spoke 42b-1 and the second spoke 42b-2 12 In the embodiment, the magnetic pole portion 42c-1x and the magnetic pole portion 42c-2y, both of which have a large magnetic resistance Rm, are close to each other, and in at least one narrow slot, the magnetic pole portions, both of which have a large magnetic resistance Rm, are close to each other (condition A). As a result, the aspect of being able to further increase the tooth slot torque is the same as the fourth embodiment.

[0182] In this embodiment, the number of spokes included in the rotor core is an odd number, and therefore, condition C described in the first embodiment is not satisfied, nor is condition D, which is peculiar to the case where the number of spokes is an odd number, described in the fourth embodiment. However, in this embodiment, as shown below, it is preferred to have another condition (condition E) peculiar to the case where the number of spokes is an odd number, which further increases the cogging torque.

[0183] First, in this embodiment, with respect to the slot 4S between the first spoke 42b-1 and the second spoke 42b-2 12 The magnetic resistance Rm (reference numeral H) of the magnetic pole portion 52c-4x on one side of the circumferential xy direction (clockwise x side) in the magnetic pole portion pair 52c-4 of the fourth b-spoke 52b-4 located at a point-symmetrical position around the rotating shaft 30 is larger than the magnetic resistance Rm (reference numeral L) of the magnetic pole portion 52c-4y on the opposite side (condition E-1).

[0184] In addition, in the present embodiment, the magnetic resistance Rm (reference numeral L) of the magnetic pole portion 52c-3x on the fourth b spoke 52b-4 side in the circumferential direction xy of the magnetic pole portion 52c-3 of the third b spoke 52b-3 adjacent to the fourth b spoke 52b-4 on the magnetic pole portion 52c-4y side having a small magnetic resistance Rm in the magnetic pole portion pair 52c-4 possessed by the fourth b spoke 52b-4 is smaller than the magnetic resistance Rm (reference numeral H) of the magnetic pole portion 42c-1x on one side (clockwise direction x side) of the magnetic pole portion pair 42c-1 possessed by the first spoke 42b-1 (condition E-2).

[0185] Satisfying the above conditions E-1 and E-2 is condition E, and in the present embodiment, condition E is satisfied.

[0186] As described above, in the present embodiment, the slot 4S is located close to the magnetic pole portions having a large magnetic resistance Rm. 12 In the narrow slot between the spoke at the point-symmetrical position and the spoke located next to it, the magnetic pole portions are close to each other (in this embodiment, the magnetic pole portion 52c-3x is small (reference numeral L), but it can also be medium (reference numeral M)). Therefore, it is estimated that the magnetic balance is further destroyed in the circumferential direction xy, and therefore the cogging torque is further increased.

[0187] [Sixth Embodiment]

[0188] Next, a motor according to a sixth embodiment of the present invention will be described with reference to the accompanying drawings. The motor according to the sixth embodiment is similar in structure to the motor 1 according to the first embodiment except that the shape of the rotor core is different. Therefore, in this embodiment, a cross-sectional view showing only the rotor core (core) 62 and the rotating shaft 30 is used. Fig.10 Provide explanation.

[0189] However, in this embodiment, the number of spokes included in the rotor core is different from that of the motor 1 of the first embodiment, and accordingly, the magnets, the circuit configuration of the control board, and the like are different from those of the motor 1 of the first embodiment.

[0190] In the present embodiment, the rotor core 62 has: an annular portion 62a, surrounding the rotating shaft 30; and eleven spokes 62b-1 to 62b-11, extending radially (radially) from the annular portion 62a with the rotating shaft 30 as the axis. The rotor core 62 has a pair of magnetic pole portions (magnetic pole portion pairs 62c-1 to 62c-11) extending in two directions of the circumferential direction xy at the ends of the radial directions mn (especially, the outer direction m) of each of the odd-numbered (eleven) spokes 62b-1 to 62b-11. It should be noted that the rotor coils (coils) are respectively wound around the eleven spokes 62b-1 to 62b-11, but in Fig.10 In the seventh embodiment, the illustration is omitted. Fig.11 The same is true in Chinese.

[0191] First, in Fig.10 In the figure, the spoke on the counterclockwise y side of the two spokes extending from the annular portion 62a in the downward direction d is set as the first spoke 62b-1, and from the first spoke 62b-1 in the clockwise direction x, they are successively set as the second spoke 62b-2, the sixth spoke 62b-6, the seventh spoke 62b-7, the eighth spoke 62b-8, the third a spoke 62b-3, the fourth a spoke 62b-4, the fifth a spoke 62b-5, the ninth spoke 62b-9, the tenth spoke 62b-10 and the eleventh spoke 62b-11.

[0192] In this embodiment, in the first spoke 62b-1, the magnetic resistance Rm (reference numeral H) of the magnetic pole portion 62c-1x on one side of the circumferential direction xy (clockwise direction x side) is larger than the magnetic resistance Rm (reference numeral L) of the magnetic pole portion 62c-1y on the other side of the circumferential direction xy (counterclockwise direction y side).

[0193] In addition, in the second spoke 62b-2, the magnetic resistance Rm (reference numeral H) of the magnetic pole portion 62c-2y on the other side of the circumferential direction xy (the counterclockwise direction y side) is larger than the magnetic resistance Rm (reference numeral L) of the magnetic pole portion 62c-2x on one side of the circumferential direction xy (the clockwise direction x side).

[0194] In addition, in the third a-spoke 62b-3, the magnetic resistance Rm (reference numeral H) of the magnetic pole portion 62c-3y on the other side of the circumferential direction xy (the counterclockwise direction y side) is larger than the magnetic resistance Rm (reference numeral L) of the magnetic pole portion 62c-3x on one side of the circumferential direction xy (the clockwise direction x side).

[0195] In addition, in the fifth a-spoke 62b-5, the magnetic resistance Rm (reference numeral H) of the magnetic pole portion 62c-5x on one side of the circumferential direction xy (clockwise direction x side) is larger than the magnetic resistance Rm (reference numeral L) of the magnetic pole portion 62c-5y on the other side of the circumferential direction xy (counterclockwise direction y side).

[0196] On the other hand, in the magnetic pole pair 62c-4 of the fourth a-spoke 62b-4, the magnetic resistance Rm of the magnetic poles 62c-4x and 62c-4y on one side (clockwise x side) and the other side (counterclockwise y side) in the circumferential direction xy is approximately equal (reference numeral M).

[0197] In this embodiment, in the magnetic pole portion pairs 62c-6 to 62c-11 of the sixth to eleventh spokes 62b-6 to 62b-11 other than the above-mentioned ones, the magnetic resistance Rm of the magnetic pole portions 62c-6x to 62c-11x, 62c-6y to 62c-11y on one side (clockwise direction x side) and the other side (counterclockwise direction y side) of the circumferential direction xy is approximately equal (reference numeral M in the figure).

[0198] In this embodiment, if Fig.10 As shown, regarding the magnetic pole pair 62c-0 of four spokes 62b-0 (0 is filled with any number of 1, 2, 3 and 5. The same applies to the present embodiment below) among the eleven spokes 62b-1 to 62b-11, the magnetic resistance Rm of the magnetic pole 62c-0x on one side of the circumferential direction xy (clockwise direction x side) and the magnetic resistance Rm of the magnetic pole 62c-0y on the other side of the circumferential direction xy (counterclockwise direction y side) are different. Therefore, in the present embodiment, the magnetic balance in the circumferential direction is destroyed, and the increase of the cogging torque is achieved.

[0199] In addition, in this embodiment, if Fig.10 As shown, the slot 6S between the first spoke 62b-1 and the second spoke 62b-2 12 In this way, in at least one slot, the magnetic pole portions 62c-1x and 62c-2y, both of which have large magnetic resistance Rm, are close to each other. This further increases the cogging torque.

[0200] In addition, in the present embodiment, the number of spokes included in the rotor core is eleven, which is preferable in terms of satisfying the condition D which is unique to the case where the number of spokes is an odd number. That is, in the present embodiment, the slot 6S between the first spoke 62b-1 and the second spoke 62b-2 is 12 The magnetic resistances of the two magnetic pole portions 62c-4x and 62c-4y of the magnetic pole portion pair 62c-4 of the fourth a-spoke 62b-4 located at a point symmetrical position about the rotation shaft 30 are substantially equal (condition D-1).

[0201] In addition, in the present embodiment, the magnetic resistance Rm (reference numeral L) of at least one of the magnetic pole portion 62c-3x on the circumferential side of the fourth a spoke 62b-4 in the magnetic pole portion pair 62c-3 of the third a spoke 62b-3 and the magnetic pole portion 62c-5y on the circumferential side of the fourth a spoke 62b-4 in the magnetic pole portion pair 62c-5 of the fifth a spoke 62b-5 is smaller than the magnetic resistance Rm (reference numeral M for both 62c-4x and 62c-4y) of one of the magnetic pole portions in the magnetic pole portion pair 62c-4 of the fourth a spoke 62b-4 (condition D-2).

[0202] In the present embodiment, the above conditions D-1 and D-2 are satisfied, and therefore condition D is satisfied. It should be noted that in condition D-2, the scheme of the present embodiment in which both the magnetic pole portion 62c-3x and the magnetic pole portion 62c-5y have smaller magnetic resistance Rm than the magnetic pole portion 62c-4x (≒62c-4y) is particularly preferred.

[0203] As described above, in the present embodiment, the slots 6S are located in a state where the magnetic pole portions having a large magnetic resistance Rm are close to each other. 12 By setting the magnetic resistance Rm to be small on at least one side of the spokes at the point-symmetric position, it is estimated that the manner in which the magnetic balance is destroyed in the circumferential direction xy further increases, and therefore the cogging torque further increases.

[0204] [Seventh Embodiment]

[0205] Next, a motor according to a seventh embodiment of the present invention will be described with reference to the drawings. The motor according to the seventh embodiment is similar in structure to the motor 1 according to the first embodiment except that the shape of the rotor core is different. Therefore, in this embodiment, a cross-sectional view showing only the rotor core 72 and the rotating shaft 30 is used. Fig.11 Provide explanation.

[0206] The rotor core 72 in this embodiment corresponds to only the magnetic pole pair 62c-3 and 62c-4 of the third a-spoke 62b-3 and the fourth a-spoke 62b-4 among the eleven spokes 62b-1 to 62b-11 in the sixth embodiment ( Fig.11 The shapes of the reference numerals 72c-3 and 72c-4 in the figure are different, and the other shapes and structures are the same as those of the rotor core 62 in the sixth embodiment. Fig.11 In the present invention, the same reference numerals are given to components having the same configuration as those in the sixth embodiment, and detailed description thereof is omitted.

[0207] It should be noted that the fifth b-spoke 72b-5 in this embodiment is the same as the fifth a-spoke 62b-5 in the sixth embodiment, but for the sake of convenience, a unique reference numeral (72b-5) is marked in this embodiment. The same is true for the components (magnetic pole portion, magnetic pole portion pair, etc.) related to the fifth b-spoke 72b-5.

[0208] In this embodiment, in the magnetic pole portion pair 72c-4 of the fourth b-spoke 72b-4, the magnetic resistance Rm (reference numeral H) of the magnetic pole portion 72c-4x on one side of the circumferential direction xy (clockwise direction x side) is larger than the magnetic resistance Rm (reference numeral L) of the magnetic pole portion 72c-4y on the other side of the circumferential direction xy (counterclockwise direction y side).

[0209] On the other hand, in the magnetic pole pair 72c-3 of the third b-spoke 72b-3, the magnetic resistances Rm of the magnetic poles 72c-3x and 72c-3y on one side (clockwise x side) and the other side (counterclockwise y side) in the circumferential direction xy are substantially equal (reference numeral M).

[0210] In this embodiment, if Fig.11 As shown, regarding four spokes 62b-Δ (fill Δ with 1 or 2. hereinafter, the same as in the present embodiment) and 72b-□ among the eleven spokes 62b-○ (○ is filled with any number from 1 to 11 (except 3 to 5). hereinafter, the same also applies to the present embodiment), 72b-3, 72b-□ (fill □ with 4 or 5. hereinafter, the same also applies to the present embodiment), the magnetic resistance Rm of the magnetic pole portions 62c-Δx and 72c-□x on one side of the circumferential direction xy (the x side in the clockwise direction) is different from the magnetic resistance Rm of the magnetic pole portions 62c-Δy and 72c-□y on the other side of the circumferential direction xy (the y side in the counterclockwise direction). Therefore, in the present embodiment, the aspect of achieving an increase in the cogging torque in a state where the circumferential magnetic balance is destroyed is the same as in the sixth embodiment.

[0211] In addition, the slot 6S between the first spoke 62b-1 and the second spoke 62b-2 12In the embodiment, the magnetic pole portion 62c-1x and the magnetic pole portion 62c-2y, both of which have a large magnetic resistance Rm, are close to each other, and in at least one narrow slot, the magnetic pole portions, both of which have a large magnetic resistance Rm, are close to each other (condition A). Thus, the aspect of being able to further increase the tooth slot torque is the same as the sixth embodiment.

[0212] Furthermore, in the present embodiment, the number of spokes included in the rotor core is eleven, which is preferable in terms of satisfying other conditions E that are specific to the case where the number of spokes is an odd number. That is, in the present embodiment, the slot 6S between the first spoke 62b-1 and the second spoke 62b-2 is 12 The magnetic resistance Rm (reference numeral H) of the magnetic pole portion 72c-4x on one side of the circumferential xy direction (clockwise x side) in the magnetic pole portion pair 72c-4 of the fourth b-spoke 72b-4 located at a point-symmetrical position around the rotating shaft 30 is larger than the magnetic resistance Rm (reference numeral L) of the magnetic pole portion 72c-4y on the opposite side (condition E-1).

[0213] In addition, in the present embodiment, the magnetic resistance Rm (reference numeral M) of the magnetic pole portion 72c-3x on the fourth b spoke 72b-4 side in the circumferential direction xy of the magnetic pole portion 72c-4y side of the magnetic pole portion 72c-4 of the third b spoke 72b-3 adjacent to the fourth b spoke 72b-4 in the magnetic pole portion pair 72c-3 having a small magnetic resistance Rm in the fourth b spoke 72b-4 is smaller than the magnetic resistance Rm (reference numeral H) of the magnetic pole portion 62c-1x on one side (clockwise direction x side) of the magnetic pole portion pair 62c-1 of the first spoke 62b-1 (condition E-2).

[0214] The above conditions E-1 and E-2 are met, therefore, condition E is met.

[0215] As described above, in the present embodiment, the slot 6S is located close to the magnetic pole portions having a large magnetic resistance Rm. 12 In the narrow slot between the spoke at the point-symmetrical position and the spoke located next to it, the magnetic poles are close to each other in a state where the magnetic resistance Rm is small (as in the present embodiment, the magnetic pole portion 72c-3x may also be medium (reference numeral M)). Therefore, it is estimated that the magnetic balance is further destroyed in the circumferential direction xy, and therefore the cogging torque is further increased.

[0216] [Eighth Embodiment]

[0217] Next, a motor according to an eighth embodiment of the present invention will be described with reference to the drawings. Fig.12 is a cross-sectional view of a motor 8 according to an eighth embodiment, taken along a plane perpendicular to the axis. Fig.13 It is a cross-sectional view of a plane including the axis. Fig.12yes Fig.13 In the CC section view, Fig.13 yes Fig.12 DD section view in.

[0218] In the motor 8 of the eighth embodiment, a member having the same configuration as the rotor (rotor core 2 and rotor coil 3) of the motor 1 of the first embodiment is used as a stator (reference numeral 80 in this embodiment). That is, the motor 1 is an inner rotor type motor, whereas the motor 8 is an outer rotor type motor.

[0219] In addition, although there are various differences in the shape of the magnets, the structure of the shaft support, etc., the motor 8 of this embodiment is similar to the motor 1 of the first embodiment. Fig.12 and Fig.13 In the present invention, the same reference numerals are given to the components having the same configuration as those in the first embodiment, and detailed description thereof will be omitted.

[0220] In this embodiment, the rotor 81 has a magnet 81a and a rotor hub 81b. The rotor hub 81b is coaxially arranged with the rotating shaft 30 and is cup-shaped as a whole, including: a cylindrical portion 81c, on the inner circumference of which the magnet 81a is mounted; a disc portion 81e, in one direction ( Fig.13 and a cylindrical connecting portion 81d, which is connected to the disc portion 81e.

[0221] The rotor hub 81b is a magnetic body such as iron material, and the rotating shaft 30 inserted into the connecting portion 81d is fixed to the connecting portion 81d, and the two are integrated. Six magnets 81a are arranged on the inner circumferential surface of the cylindrical portion 81c so as to surround the stator core 82 described later. The magnets 81a are arranged so that the N poles and the S poles are alternately opposed to the stator core 82 in the circumferential direction.

[0222] A stator core 82 as a part of the iron stator 80 is arranged inside the magnet 81a with a predetermined gap. In the present embodiment, the stator 80 includes: the stator core 82, which is composed of an annular portion 82a arranged coaxially with the rotating shaft 30 and surrounding the rotating shaft 30, and six spokes 82b extending radially (radially) from the annular portion 82a; and a stator hub 82e extending from the annular portion 82a in the other direction (axial direction) of the rotating shaft 30. Fig.13 The right direction in the middle) side extends radially (radially) and expands in diameter; and a stator coil (coil) 83, which is respectively wound around the six spokes 82b of the stator core 82.

[0223] In the annular portion 82a, in the axial direction of the rotating shaft 30, from one direction to the other direction (from Fig.13The spoke 82b and the stator hub 82e are connected in sequence (from the left direction in the figure to the right direction), and the annular portion 82a is further extended (the extended portion is called "annular extension portion" and is marked with the reference numeral 82f). A disc-shaped bottom portion 61 is installed on a part of the annular extension portion 82f and the stator hub 82e. The bottom portion 61 and the stator 80 constitute a fixed portion.

[0224] The rotating shaft 30 is slightly closer to the center of the axial direction ( Fig.13 left direction) side and the other direction ( Fig.13 The first bearing 40 and the second bearing 41 are supported in a rotatable state on the right side of the annular portion 82a. The first bearing 40 and the second bearing 41 are respectively fixed to the inner peripheral surface of the annular portion 82a, and are fixed to the stator 80 via these bearings 40 and 41. That is, the rotating shaft 30 is fixed to be rotatable relative to the stator 80. Therefore, the rotating part composed of the rotating shaft 30 and the rotor 81 is set to be rotatable relative to the fixed part composed of the stator 80 and the bottom 61.

[0225] The stator 80 is provided with a power supply mechanism (not shown), and a predetermined driving current is supplied to the stator coil 83 wound around the stator core 82 through the power supply mechanism. The mechanical and electrical structures of the stator 80 are the same as those of a general brushless DC motor.

[0226] Fig.14 This is a cross-sectional view of the motor 8 of this embodiment, in which only the stator core 82 is extracted. Figure 3 By comparison, it can be seen that the shape of the stator core 82 in this embodiment is the same as that of the rotor core 2 in the first embodiment. Fig.13 ) and the rotor coil 3 in the first embodiment (see Figure 1 ) also has the same structure. The stator 80 in this embodiment and the rotor 20 in the first embodiment can be said to be the same part when viewed as a single part.

[0227] That is, the stator 80 in this embodiment and the rotor 20 in the first embodiment can be regarded as the same magnetic component. Therefore, although the stator 80 and the rotor 20 have different functions in the motors (8, 9), they show the same characteristics as magnetic characteristics. Therefore, the motor 8 in this embodiment can enjoy the effect of increasing the cogging torque in the same way as the motor 1 in the first embodiment.

[0228] In the present embodiment, the magnetic resistance Rm of the magnetic pole portion 82c-0x (0 is filled with any number from 1 to 6. The same also applies to the present embodiment below) on one side (clockwise x side) of the circumferential direction xy of all the magnetic pole portion pairs 82c-1 to 82c-6 of the six spokes 82b-1 to 82b-6 is different from the magnetic resistance Rm of the magnetic pole portion 82c-0y on the other side (counterclockwise y side) of the circumferential direction xy. Therefore, in the present embodiment, the magnetic balance in the circumferential direction is destroyed, and the cogging torque is increased.

[0229] In the present embodiment, the magnetic pole portion 82c-2y on the other side (the counterclockwise y side) of the magnetic pole portion pair 82c-2 of the second spoke 82b-2 in the circumferential direction xy has a larger magnetic resistance Rm than the magnetic pole portion 82c-2x on one side (the clockwise x side) in the circumferential direction xy.

[0230] Therefore, if Fig.14 As shown, the slot 8S between the first spoke 82b-1 and the second spoke 82b-2 12 In this way, in at least one slot, the magnetic pole portions 82c-1x and 82c-2y, both of which have large magnetic resistance Rm, are close to each other. This further increases the cogging torque.

[0231] In addition, in the present embodiment, the magnetic resistance Rm (reference numeral M) of the magnetic pole portion 82c-3y on the other side of the circumferential direction xy (the counterclockwise direction y side) in the magnetic pole portion pair 82c-3 of the third spoke 82b-3 adjacent to the second spoke 82b-2 on one side of the circumferential direction xy (the clockwise direction x side) is smaller than the magnetic resistance Rm (reference numeral H) of the magnetic pole portion 82c-2y on the other side of the circumferential direction xy (the counterclockwise direction y side) in the magnetic pole portion pair of the second spoke 82b-2.

[0232] Therefore, if Fig.14 As shown, the slot 8S between the second spoke 82b-2 and the third spoke 82b-3 23 In the embodiment, the magnetic pole portion 82c-2x and the magnetic pole portion 82c-3y are close to each other in the state where the magnetic resistance Rm is small. That is, the slot 8S between the first spoke 82b-1 and the second spoke 82b-2 is close to the magnetic pole portion 82c-1x and the magnetic pole portion 82c-2y in the state where the magnetic resistance Rm is large. 12 The adjacent slot 8S 23 In the figure, the magnetic pole portion 82c-2x and the magnetic pole portion 82c-3y, both of which have small magnetic resistance Rm, are close to each other. Therefore, in the circumferential direction xy, the portion with large magnetic resistance Rm is close to the portion with small magnetic resistance Rm, and the magnetic balance is more likely to be destroyed.

[0233] In this way, two slits 8S are continuous in the circumferential direction. 12 、8S 23 In the slot 8S, each of which is located on one side 12 The magnetic poles with large magnetic resistance Rm (H) are close to each other, and the slot 8S on the other side is 23 In a state where the magnetic pole portions where the magnetic resistance Rm is small (reference symbol L) are close to each other, the portion with large magnetic resistance Rm is brought close to the portion with small magnetic resistance Rm (condition B), thereby further increasing the cogging torque.

[0234] In the present embodiment, the number of spokes of the stator core 82 is an even number, and the first spoke 82b-1 is located at a position about the rotation axis 30 (see Fig.12 ) as the center of the point symmetrical position, the magnetic pole portion 82c-4 has a pair of magnetic pole portions 82c-4, the magnetic resistance Rm of the magnetic pole portion 82c-4y is small (reference numeral L), and the magnetic resistance Rm of the magnetic pole portion 82c-4x is large (reference numeral H).

[0235] On the other hand, in the position relative to the second spoke 82b-2 and located at the rotation axis 30 (refer to Fig.12 ) as the center, the magnetic pole portion 82c-5 has a pair of magnetic pole portions 82c-5, the magnetic resistance Rm of the magnetic pole portion 82c-5x is small (reference numeral L), and the magnetic resistance Rm of the magnetic pole portion 82c-5y is large (reference numeral H).

[0236] Therefore, if Fig.14 As shown, in the slot 8S between the first spoke 82b-1 and the second spoke 82b-2 12 Located at the rotation axis 30 (refer to Fig.12 ) is centered at a point symmetrically located between the fourth spoke 82b-4 and the fifth spoke 82b-5. 45 In the state where the magnetic pole portion 82c-4x and the magnetic pole portion 82c-5y, both of which have large magnetic resistance Rm, are close to each other.

[0237] As described above, the slot 8S between the first spoke 82b-1 and the second spoke 82b-2 12 In the embodiment, the magnetic pole portion 82c-1x and the magnetic pole portion 82c-2y, both of which have large magnetic resistance Rm, are close to each other. Therefore, in the circumferential direction xy, the slots in which the magnetic pole portions with large magnetic resistance Rm are close to each other are located at point-symmetrical positions.

[0238] As described above, in the present embodiment, the slots in a state where the magnetic pole portions having large magnetic resistance Rm are close to each other are located at point-symmetrical positions (condition C), thereby synergistically increasing the cogging torque.

[0239] It should be noted that in this embodiment, the shape of the stator core 82 is exemplified as the same shape as the rotor core 2 in the first embodiment, but it is not limited to this. For example, the stator core 82 can be replaced with a stator core having the same shape as any of the rotor cores exemplified in the second to seventh embodiments, and the effects of the present invention can be exerted in any shape.

[0240] [Ninth Embodiment]

[0241] Next, a motor according to a ninth embodiment of the present invention will be described with reference to the drawings. Fig.15 It is a cross-sectional view of a motor 9 according to the ninth embodiment, taken along a plane perpendicular to the axis.

[0242] The motor 9 of the ninth embodiment is the same as the motor 1 of the first embodiment and is an inner rotor type motor; however, the structure of the rotor (rotor core 2 and rotor coil 3 in the first embodiment) and the stator (stator 10 in the first embodiment) is significantly different from that of the motor 1.

[0243] That is, in the motor 1 of the first embodiment, a magnetic member having a plurality of (six) spokes 2b with a magnetic pole pair 2c at the top facing outward and arranged radially and having coils 3 wound thereon is used as a rotor. In contrast, in the motor 9 of the present embodiment, a magnetic member having a plurality of (six) spokes 92b with a magnetic pole pair 92c at the top facing outward and arranged radially and having stator coils (coils) 93 wound thereon is used as a stator 90.

[0244] Along with the difference in the structure of the magnetic component, in this embodiment, the structure of the rotor 91 is not only different from the rotor in the first embodiment, but also greatly different from the stator 10. That is, the rotor 91 in this embodiment is a cylindrical component in which the rotating shaft 30 is inserted and fixed in the inner hole, and the outer surface is magnetized in a manner that the S pole and the N pole are alternately arranged in the circumferential direction to form a magnet. It should be noted that it is also possible that, as the rotor 91, a magnet is embedded in the outer surface of the cylindrical component, and the S pole and the N pole are also alternately arranged.

[0245] A stator 92 having spokes 92b with a pair of magnetic poles 92c facing each other is disposed outside a rotor 91 having a magnet on its outer peripheral surface with a predetermined gap therebetween. The stator 90 includes a stator core 92 having six spokes 92b and stator coils 93 wound around the spokes 92b.

[0246] The stator core 92 is a laminate of silicon steel plates, etc., and has an annular portion 92a surrounding the rotating shaft 30, and the spokes 92b extending radially from the inner circumference of the annular portion 92a toward the central axis side (rotating shaft 30 side) in a radial direction (in a radial shape). It should be noted that a cylindrical housing 94 is arranged outside the annular portion 92a of the stator core 92, and the stator 90 is fixed to the housing 94.

[0247] The stator core 92 has a pair of magnetic pole portions extending in two directions along the circumferential directions xy at the ends of the radial directions mn (especially, the inner direction n) of each of the multiple (six) spokes 92b (the pair of magnetic pole portions are sometimes collectively referred to as a "magnetic pole portion pair". In the present embodiment, when a pair of magnetic pole portions are collectively referred to as a "magnetic pole portion pair", they are marked with the figure mark "92c" or the figure mark "92c-□" (□ is an integer)).

[0248] It should be noted that in this embodiment, the cross-sectional view of the plane including the shaft of the motor 9 is omitted, but the rotating shaft 30 has two inner rings of bearings not shown fixed in the axial direction of the rotating shaft 30, and the outer rings of the bearings are fixed to the housing 94, thereby setting the rotor 91 to a rotatable state relative to the stator 90.

[0249] Fig.16 This is a cross-sectional view of only the rotor core 92 extracted from the motor 9 of the present embodiment. Fig.16 The rotor core 92 shown has a pair of magnetic pole portions 92c-1x to 92c-6x, 92c-1y to 92c-6y having shapes different from each other in at least one spoke (in the present embodiment, all spokes 92b-1 to 92b-6) among an even number of spokes (six spokes in the present embodiment).

[0250] The following will be described in more detail.

[0251] First, in Fig.16 The spoke extending downwardly from the annular portion 92a is a first spoke 92b-1, and the second spoke 92b-2, the third spoke 92b-3, the fourth spoke 92b-4, the fifth spoke 92b-5 and the sixth spoke 92b-6 are sequentially arranged in the clockwise direction x from the first spoke 92b-1.

[0252] Fig.17 2 is an enlarged view of the periphery of the tip end portion of each spoke 92b (the periphery of the magnetic pole portion 92c) in the motor according to the ninth embodiment.

[0253] In the first spoke 92b-1, in the magnetic pole pair 92c-1 at the end in the inner direction n, the rotor 91 (refer to Fig.15 ) is provided on the surface facing the magnet of the rotating shaft 30 with a groove portion 92ch extending parallel to the axial direction of the rotating shaft 30.

[0254] like Fig.17 As shown in FIG. 1 , the groove 92ch is located in the magnetic pole pair 92c-1 at a position deviated from the center in the circumferential direction xy to the clockwise x side (the second spoke 92b-2 side). Fig.17 As shown, the cross-sectional area of ​​the magnetic pole portion 92c-1x on the clockwise x side of the magnetic pole portion pair 92c-1 is small, and the cross-sectional area of ​​the magnetic pole portion 92c-1y on the counterclockwise y side is large.

[0255] Therefore, in the magnetic pole pair 92c-1, if the position of the groove 92ch is deviated from the center in the circumferential direction xy, compared with the case where it is located at the center, as shown in FIG. Fig.17 As shown, the magnetic resistance Rm of the magnetic pole portion 92c-1x on the side close to the groove portion 92ch is large (reference symbol H), and the magnetic resistance Rm of the magnetic pole portion 92c-1y on the side away from the groove portion 92ch is small (reference symbol L).

[0256] Therefore, in the first spoke 92b-1, the magnetic pole portion 92c-1x on one side in the circumferential direction xy (clockwise direction x side) has a larger magnetic resistance Rm than the magnetic pole portion 92c-1y on the other side in the circumferential direction xy (counterclockwise direction y side).

[0257] In this embodiment, all the magnetic pole pairs 92c-1 to 92c-6 of the six spokes 92b-1 to 92b-6 have the same groove 92ch as the first spoke 92b-1, and the position of the groove 92ch is offset from the center in the circumferential direction xy in any direction (x direction or y direction).

[0258] In the magnetic pole portion pair 92c-2 of the second spoke 92b-2 adjacent to the first spoke 92b-1 on the clockwise x side (one side in the circumferential direction xy), as shown in FIG. Fig.17 As shown in FIG. 1 , the groove portion 92ch is located at a position offset from the center in the circumferential direction xy toward the counterclockwise direction y side (the first spoke 92b-1 side). Fig.17 As shown, the cross-sectional area of ​​the magnetic pole portion 92c-2x on the clockwise x side of the magnetic pole portion pair 92c-2 is large, and the cross-sectional area of ​​the magnetic pole portion 92c-2y on the counterclockwise y side is small.

[0259] Therefore, in the magnetic pole pair 92c-2, compared with the case where the groove 92ch is located at the center in the circumferential direction xy, Fig.17 As shown, the magnetic resistance Rm of the magnetic pole portion 92c-2x on the side away from the groove portion 92ch is small (reference symbol L), and the magnetic resistance Rm of the magnetic pole portion 92c-2y on the side close to the groove portion 92ch is large (reference symbol H).

[0260] Therefore, in the second spoke 92b-2, the magnetic pole portion 92c-2y on the other side in the circumferential direction xy (the counterclockwise direction y side) has a larger magnetic resistance Rm than the magnetic pole portion 92c-2x on one side in the circumferential direction xy (the clockwise direction x side).

[0261] Although the respective magnetic pole pairs 92c-1 and 92c-2 in these first spokes 92b-1 and second spokes 92b-2 are different from the respective magnetic pole pairs 2c-1 and 2c-2 in the first embodiment in terms of whether they are opposite to each other on the center axis side (rotation shaft 30 side) or on the outer side (peripheral direction), in the circumferential direction, the size of the cross-sectional area of ​​the magnetic pole portion 92c, in other words, the arrangement of the size of the magnetic resistance Rm of the magnetic pole portion 92c is the same.

[0262] That is, the magnetic resistance Rm of the magnetic pole portion 92c-1y, the magnetic pole portion 92c-1x, the magnetic pole portion 92c-2y, and the magnetic pole portion 92c-2x in the clockwise direction x is the same as the magnetic resistance Rm of the magnetic pole portion 2c-1y, the magnetic pole portion 2c-1x, the magnetic pole portion 2c-2y, and the magnetic pole portion 2c-2x in the first embodiment, and if they are directly represented by the figure marks in this order, they are all L, H, H, and L. The remaining magnetic pole portions 92c-3y to 92c-6y and the magnetic pole portions 92c-3x to 92c-6x are also the same as the magnetic pole portions 2c-3y to 2c-6y and the magnetic pole portions 2c-3x to 2c-6x in the first embodiment.

[0263] Therefore, in this embodiment, the same action and effect related to the cogging torque as in the first embodiment are also exerted. That is, in this embodiment, with respect to all the magnetic pole pairs 92c-1 to 92c-6 possessed by the six spokes 92b-1 to 92b-6, the magnetic resistance Rm of the magnetic poles 92c-1x to 92c-6x on one side of the circumferential direction xy (the x side in the clockwise direction) and the magnetic resistance Rm of the magnetic poles 92c-1y to 92c-6y on the other side of the circumferential direction xy (the y side in the counterclockwise direction) are different from each other. Therefore, in this embodiment, the magnetic balance in the circumferential direction is destroyed, and the cogging torque is increased.

[0264] In the present embodiment, the magnetic pole portion 92c-2y on the other side (counterclockwise y side) of the magnetic pole portion pair 92c-2 of the second spoke 92b-2 in the circumferential direction xy has a larger magnetic resistance Rm than the magnetic pole portion 92c-2x on one side (clockwise x side) in the circumferential direction xy.

[0265] Therefore, if Fig.17 As shown, the slot 9S between the first spoke 92b-1 and the second spoke 92b-2 12In this way, in at least one slot, the magnetic poles (reference numeral H) with large magnetic resistance Rm are close to each other (condition A), thereby further increasing the cogging torque.

[0266] In addition, in the present embodiment, the magnetic resistance Rm (reference numeral L) of the magnetic pole portion 92c-3y on the other side of the circumferential direction xy (the counterclockwise direction y side) of the magnetic pole portion pair 92c-3 of the third spoke 92b-3 adjacent to the second spoke 92b-2 on one side of the circumferential direction xy (the clockwise direction x side) is smaller than the magnetic resistance Rm (reference numeral H) of the magnetic pole portion 92c-2y on the other side of the circumferential direction xy (the counterclockwise direction y side) of the magnetic pole portion pair 92c-2 of the second spoke 92b-2.

[0267] Therefore, if Fig.17 As shown, the narrow groove 9S between the second spoke 92b-2 and the third spoke 92b-3 23 In the embodiment, the magnetic pole portion 92c-2x and the magnetic pole portion 92c-3y are close to each other in the state where the magnetic resistance Rm is small. That is, the slot 9S between the first spoke 92b-1 and the second spoke 92b-2 is close to the magnetic pole portion 92c-1x and the magnetic pole portion 92c-2y in the state where the magnetic resistance Rm is large. 12 The adjacent slot 9S 23 In contrast, the magnetic pole portion 92c-2x with a small magnetic resistance Rm is close to the magnetic pole portion 92c-3y. Therefore, in the circumferential direction xy, the portion with a large magnetic resistance Rm is close to the portion with a small magnetic resistance Rm, and the magnetic balance is more destructed.

[0268] Like this, two slits 9S are continuous in the circumferential direction. 12 、9S 23 In the slots 9S on either side 12 The magnetic poles with large magnetic resistance Rm (H) are close to each other, and the slot 9S on the other side is 23 The magnetic pole portions are in a state close to each other (condition B) where the magnetic resistance Rm is small (reference symbol L), thereby further increasing the cogging torque.

[0269] In the present embodiment, the number of spokes of the stator core 92 is an even number, and the first spoke 92b-1 is located about the rotation axis 30 (see Fig.15 ) as the center of the point symmetric position of the fourth spoke 92b-4 has a magnetic pole portion pair 92c-4, the magnetic pole portion 92c-4y has a small magnetic resistance Rm (reference numeral L), and the magnetic pole portion 92c-4x has a large magnetic resistance Rm (reference numeral H).

[0270] On the other hand, in the position relative to the second spoke 92b-2 and located at the rotation axis 30 (refer to Fig.15 ) as the center of the point symmetrical position, the magnetic pole portion 92c-5 has a pair of magnetic pole portions 92c-5, the magnetic resistance Rm of the magnetic pole portion 92c-5x is small (reference numeral L), and the magnetic resistance Rm of the magnetic pole portion 92c-5y is large (reference numeral H).

[0271] Therefore, if Figure 7 As shown, in the slot 9S between the first spoke 92b-1 and the second spoke 92b-2 12 Located at the rotation axis 30 (refer to Fig.15 ) is centered at a point symmetrically located between the fourth spoke 92b-4 and the fifth spoke 92b-5. 45 In the state where the magnetic pole portion 92c-4x and the magnetic pole portion 92c-5y are close to each other and both magnetic resistances Rm are large (reference numeral H).

[0272] As described above, the slot 9S between the first spoke 92b-1 and the second spoke 92b-2 12 In the embodiment, the magnetic pole portion 92c-1x and the magnetic pole portion 92c-2y, both of which have large magnetic resistance Rm, are close to each other. Therefore, in the circumferential direction xy, the slots in which the magnetic pole portions with large magnetic resistance Rm are close to each other are located at point-symmetrical positions.

[0273] As described above, in the present embodiment, the slots in a state where the magnetic pole portions having large magnetic resistance Rm are close to each other are located at point-symmetrical positions (condition C), thereby synergistically increasing the cogging torque.

[0274] In this embodiment, the stator 90, which is a characteristic magnetic member of the present invention, is fixed, and a predetermined current is supplied to the stator coil 93 provided in the stator 90, thereby taking the inner rotor type motor 9 in which the rotating shaft 30 rotates together with the rotor 91 located inside the stator 90 as an example for explanation. However, similarly to the relationship between the eighth embodiment and the first embodiment, even if the functions of the rotor and the stator are exchanged, the function and effect of the present invention can be exerted.

[0275] That is, in this embodiment, a magnetic component having the same shape and structure as the stator 80 is rotatably supported relative to the housing 94, thereby setting it as a rotor. On the other hand, a component equivalent to the rotor 81 is fixed to the housing 94 in a manner independent of the rotating shaft 30, thereby, in an outer rotor type motor in which it is set as a stator, the function and effect of the present invention can also be achieved.

[0276] The motor of the present invention has been described above by taking a preferred embodiment as an example, but the motor of the present invention is not limited to the configuration of the above embodiment. For example, in the above embodiment, the number of spokes is five, six, and eleven as examples for description, but the number of spokes is not particularly limited, as long as it is a plurality. In addition, regarding condition C which is specific to an even number of spokes, the number of spokes is not limited to six, but may be four, eight, or more. Moreover, regarding condition D and condition E which are specific to an odd number of spokes, the number of spokes is not limited to five or eleven, but may be three, seven, or nine, or may be thirteen or more.

[0277] Furthermore, in the above-mentioned embodiment, as methods for adjusting the magnetic resistance of the magnetic pole portion of each spoke, two methods are cited: a method of offsetting the position of the slot in the magnetic pole portion and a method of offsetting the position of the crimping portion. However, the present invention is not limited to this. For example, any method such as a method of changing the size of the cross-sectional area of ​​the magnetic circuit in the magnetic pole portion by other methods may also be used.

[0278] In addition, the magnetic resistance Rm of the magnetic pole portion of each spoke can be exactly equal, large (reference numeral H), medium (reference numeral M), or small (reference numeral L), or have approximately equal differences or errors, or the size of each magnetic resistance Rm can be given a significant difference.

[0279] In addition, those skilled in the art can make appropriate changes to the motor of the present invention according to the conventional knowledge. It should be noted that as long as the configuration of the present invention is obtained through such changes, it is naturally included in the scope of the present invention.

[0280] Description of Reference Numerals

[0281] 1...Motor

[0282] 2...Rotor core (core)

[0283] 2a……Annular part

[0284] 2b…Spoke

[0285] 2b-1…First Spoke

[0286] 2b-2… Second spoke

[0287] 2b-3…The third spoke

[0288] 2b-4... Fourth spoke

[0289] 2b-5... The fifth spoke

[0290] 2b-6...Sixth spoke

[0291] 2c, 2c-1 to 2c-6... magnetic pole pair (a pair of magnetic poles)

[0292] 2c-1x~2c-6x、2c-1y~2c-6y……Magnetic pole part

[0293] 2ch...Slot

[0294] 3...Rotor coil (coil)

[0295] 8. Motor

[0296] 9…Motor

[0297] 10……Stator

[0298] 11. Magnets

[0299] 12...Tubular part

[0300] 20...Rotor (magnetic component)

[0301] 22...Rotor core (core)

[0302] 22b-3…The third spoke

[0303] 22b-6...Sixth Spoke

[0304] 22c-3, 22c-6... magnetic pole pair (a pair of magnetic poles)

[0305] 22c-3x, 22c-6x, 22c-3y, 22c-6y... magnetic pole

[0306] 30...Rotary shaft

[0307] 32...Rotor core (core)

[0308] 32a……Annular part

[0309] 32b-1...First Spoke

[0310] 32b-2... Second spoke

[0311] 32b-3…The Third Spoke

[0312] 32b-4...the fourth spoke

[0313] 32b-5... the fifth spoke

[0314] 32b-6...Sixth Spoke

[0315] 32c-1~32c-6……Magnetic pole pair (a pair of magnetic poles)

[0316] 32c-1x~32c-6x、32c-1y~32c-6y……Magnetic pole part

[0317] 32d...Crimp part

[0318] 40……First bearing

[0319] 41……Second bearing

[0320] 42...Rotor core (core)

[0321] 42a……Annular part

[0322] 42b-1... first spoke 42b-2... second spoke

[0323] 42b-3...the third spoke

[0324] 42b-4...the fourth spoke

[0325] 42b-5... fifth spoke

[0326] 42c-1~42c-5……Magnetic pole pair (a pair of magnetic poles)

[0327] 42c-1x~42c-5x、42c-1y~42c-5y……Magnetic pole part

[0328] 50...Gaibu

[0329] 52...Rotor core (core)

[0330] 52b-3...the third spoke

[0331] 52b-4...the fourth spoke

[0332] 52b-5... fifth spoke

[0333] 52c-3~52c-5……Magnetic pole pair (a pair of magnetic poles)

[0334] 52c-3x~52c-5x、52c-3y~52c-5y……Magnetic pole part

[0335] 60...Bottom

[0336] 61...Bottom

[0337] 62...Rotor core (core)

[0338] 62a……Annular part

[0339] 62b-1...First Spoke

[0340] 62b-2... Second spoke

[0341] 62b-3...the third spoke

[0342] 62b-4... fourth spoke

[0343] 62b-5... fifth spoke

[0344] 62b-6...the sixth spoke

[0345] 62b-7...the seventh spoke

[0346] 62b-8...Eighth Spoke

[0347] 62b-9... Ninth Spoke

[0348] 62b-10...the tenth spoke

[0349] 62b-11… Eleventh Spoke

[0350] 62c-1~62c-11……Magnetic pole pair (a pair of magnetic poles)

[0351] 62c-1x~62c-11x、62c-1y~62c-11y……Magnetic pole part

[0352] 72...Rotor core (core)

[0353] 72b-3...the third spoke

[0354] 72b-4...the fourth spoke

[0355] 72b-5... fifth spoke

[0356] 72c-3~72c-5……Magnetic pole pair (a pair of magnetic poles)

[0357] 72c-3x~72c-5x、72c-3y~72c-5y……Magnetic pole part

[0358] 80……Stator (magnetic component)

[0359] 81...Rotor

[0360] 81a……Magnet

[0361] 81b...Tubular part

[0362] 81c...Rotor hub

[0363] 81d...Connection

[0364] 82……Stator core (core)

[0365] 82a……Annular part

[0366] 82b...Spoke

[0367] 82c-1 to 82c-6: magnetic pole pair (a pair of magnetic poles)

[0368] 82c-1x~82c-6x、82c-1y~82c-6y……Magnetic pole part

[0369] 82e... stator hub

[0370] 82f...Annular extension

[0371] 83……Stator coil (coil)

[0372] 90……Stator (magnetic component)

[0373] 91...Rotor (magnet)

[0374] 92……Stator core (core)

[0375] 92a……Annular part

[0376] 92b...Spoke

[0377] 92c, 92c-1 to 92c-6 ... magnetic pole pair (a pair of magnetic poles)

[0378] 92c-1x~92c-6x、92c-1y~92c-6y……Magnetic pole part

[0379] 93……Stator coil (coil)

[0380] 94……Shell

[0381] 101...Motor

[0382] 102...Rotor core

[0383] 102b...Spoke

[0384] 102c……Magnetic pole pair

[0385] 102ch...slot

[0386] 102cx, 102cy...Magnetic pole

Claims

1. A motor, comprising: Rotating shaft; a magnetic member having a plurality of spokes extending radially from the rotating shaft; a magnet configured in a ring shape; coils, which are respectively wound around the plurality of spokes, In the radial direction, one of the magnetic member and the magnet is arranged inside the other. In the radial direction, the ends of the plurality of spokes are opposite to the magnets. Each end of the plurality of spokes has a pair of magnetic poles extending in opposite directions in the circumferential direction and a surface facing the magnet. The plurality of spokes include, in the circumferential direction, a second spoke, a third spoke located on one magnetic pole side of a pair of magnetic poles of the second spoke, and a first spoke located on the other magnetic pole side of the second spoke. In a pair of magnetic pole portions of the first spoke, the magnetic resistance of one magnetic pole portion is greater than the magnetic resistance of the other magnetic pole portion. A groove is formed on a surface of an end portion of the first spoke on a side of the second spoke relative to the first spoke. In a pair of magnetic pole portions of the second spoke, the magnetic resistance of the other magnetic pole portion is greater than the magnetic resistance of the one magnetic pole portion. A groove is formed on a surface of an end portion of the second spoke on a side of the first spoke relative to the second spoke. The magnetic resistance of a pair of magnetic poles of the third spoke is substantially equal. A groove is formed on the surface of the end of the third spoke in the circumferential direction at the center of the third spoke. The plurality of spokes is an even number, Among the plurality of spokes, the other spokes located at a point symmetrically with respect to the first spoke and centered on the rotation axis are set as fourth spokes, and the other spokes located at a point symmetrically with respect to the second spoke and centered on the rotation axis are set as fifth spokes, Of the pair of magnetic pole portions of the fourth spoke, one magnetic pole portion has a greater magnetic resistance than the other magnetic pole portion. Of the pair of magnetic pole portions of the fifth spoke, the other magnetic pole portion has a larger magnetic resistance than the one magnetic pole portion.

2. A motor, comprising: Rotating shaft; a magnetic member having a plurality of spokes extending radially from the rotating shaft; a magnet configured in a ring shape; coils, which are respectively wound around the plurality of spokes, In the radial direction, one of the magnetic member and the magnet is arranged inside the other. In the radial direction, the ends of the plurality of spokes are opposite to the magnets. Each end of the plurality of spokes has a pair of magnetic poles extending in opposite directions in the circumferential direction and a surface facing the magnet. The plurality of spokes include, in the circumferential direction, a second spoke, a third spoke located on one magnetic pole side of a pair of magnetic poles of the second spoke, and a first spoke located on the other magnetic pole side of the second spoke. In a pair of magnetic pole portions of the first spoke, the magnetic resistance of one magnetic pole portion is greater than the magnetic resistance of the other magnetic pole portion. In a pair of magnetic pole portions of the second spoke, the magnetic resistance of the other magnetic pole portion is greater than the magnetic resistance of the one magnetic pole portion. The magnetic resistance of the pair of magnetic poles of the third spoke is greater than the magnetic resistance of the other magnetic pole of the first spoke and smaller than the magnetic resistance of one magnetic pole of the first spoke. Among the plurality of spokes, the other spokes located at a point symmetrically with respect to the first spoke and centered on the rotation axis are set as fourth spokes, and the other spokes located at a point symmetrically with respect to the second spoke and centered on the rotation axis are set as fifth spokes, Of the pair of magnetic pole portions of the fourth spoke, one magnetic pole portion has a greater magnetic resistance than the other magnetic pole portion. Of the pair of magnetic pole portions of the fifth spoke, the other magnetic pole portion has a larger magnetic resistance than the one magnetic pole portion.

3. The motor according to claim 2, wherein: The magnetic resistance of a pair of magnetic pole portions of the third spoke is substantially equal.

4. The motor according to claim 2 or 3, wherein: The plurality of spokes is an even number.

5. A motor, comprising: Rotating shaft; a magnetic member having a plurality of spokes extending radially from the rotating shaft; a magnet configured in a ring shape; coils, which are respectively wound around the plurality of spokes, In the radial direction, one of the magnetic member and the magnet is arranged inside the other. In the radial direction, the ends of the plurality of spokes are opposite to the magnets. Each end of the plurality of spokes has a pair of magnetic poles extending in opposite directions in the circumferential direction and a surface facing the magnet. The plurality of spokes include, in the circumferential direction, a second spoke, a third spoke located on one magnetic pole side of a pair of magnetic poles of the second spoke, and a first spoke located on the other magnetic pole side of the second spoke. A groove is formed on a surface of an end portion of the first spoke on a side of the second spoke relative to the first spoke. A groove is formed on a surface of an end portion of the second spoke on a side of the first spoke relative to the second spoke. A groove is formed on the surface of the end of the third spoke in the circumferential direction at the center of the third spoke. Among the plurality of spokes, the other spokes located at a point symmetrically with respect to the first spoke and centered on the rotation axis are set as fourth spokes, and the other spokes located at a point symmetrically with respect to the second spoke and centered on the rotation axis are set as fifth spokes, Of the pair of magnetic pole portions of the fourth spoke, one magnetic pole portion has a greater magnetic resistance than the other magnetic pole portion. Of the pair of magnetic pole portions of the fifth spoke, the other magnetic pole portion has a larger magnetic resistance than the one magnetic pole portion.

6. The motor according to claim 5, wherein: The plurality of spokes is an even number.

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