JP2009303362A - Rotary electric machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotary electric machine improving a torque characteristic by relieving magnetic saturation in a yoke without enlarging the size of the rotary electric machine. <P>SOLUTION: A stator includes a cylindrical yoke 1, a plurality of arc-like permanent magnets 2 in which notches 12 abutting on the cylindrical yoke 1 at a center in a circumferential direction and separating the cylindrical yoke 1 in an end in the circumferential direction are formed and which are arranged on an inner peripheral face of the cylindrical yoke 1 by leaving a gap in the circumferential direction, and an auxiliary yoke 5 arranged between the cylindrical yoke 1 and the notch 12 to connect the confronted notches 12 of the adjacent permanent magnets 2. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a rotating electrical machine such as an electric motor or a generator having a permanent magnet on an inner peripheral surface of a yoke.

  As a conventional rotating electrical machine, there is an electric motor in which a permanent magnet is disposed on an inner peripheral surface of a cylindrical yoke. In such an electric motor, in order to reduce the difference in rigidity in the circumferential direction of the entire stator, the thickness of the yoke adjacent to the gap portion provided between the magnetic poles constituted by a plurality of permanent magnets is increased. (For example, refer to Patent Document 1).

JP 2007-288903 A (5th page, FIG. 2)

  In the conventional rotating electric machine, a part of the thick part of the yoke provided in the gap portion between the magnetic poles is arranged in the yoke portion connecting the adjacent magnetic poles. In some cases, magnetic saturation is relieved and torque characteristics can be improved. However, since the thick part of the yoke is arranged outside the cylindrical yoke, there is a problem that the size of the rotating electrical machine becomes large.

  The present invention has been made to solve the above-described problems, and provides a rotating electrical machine capable of improving torque characteristics by relaxing magnetic saturation in a yoke without increasing the size of the rotating electrical machine. is there.

  The rotating electrical machine according to the present invention has a cylindrical yoke and a cutout portion that is in contact with the cylindrical yoke at the center in the circumferential direction and separates the cylindrical yoke at the circumferential end, and that is Cylindrical yoke and notch so as to connect a plurality of arc-shaped permanent magnets provided on the inner peripheral surface of the cylindrical yoke with a gap in the direction and the notch facing the adjacent permanent magnet And a stator having an auxiliary yoke provided between them.

  In the rotating electrical machine according to the present invention, since the cylindrical yoke and the auxiliary yoke provided between the notches are provided so as to connect the notched portions facing each other of the adjacent permanent magnets, the size of the rotating electrical machine is increased. The torque characteristics can be improved by relaxing the magnetic saturation at the yoke.

Embodiment 1 FIG.
FIG. 1 is a cross-sectional view seen from the axial direction of a rotating electrical machine according to Embodiment 1 for carrying out the present invention. FIG. 2 is a cross-sectional view of the rotating electrical machine. 1 and 2, four permanent magnets 2 (2 a to 2 d) are provided on the inner surface of a cylindrical yoke 1. Further, on the inner peripheral side, a rotor 20 including a rotor core 3, a rotating shaft 4, an armature winding 7 disposed in a slot 6 provided in the rotor core 3, and a commutator 9 is disposed. A brush 8 is provided for energizing the commutator 9 with current.

  The cylindrical yoke 1 is formed by drawing a plate material having a uniform plate thickness, and one of the bracket portions for supporting the bearing is formed integrally with the cylindrical portion. Each of the four permanent magnets 2 is magnetized in a uniform direction, and different polarities are alternately arranged in the circumferential direction. For example, the permanent magnets 2a and 2c are magnetized so that the inner peripheral surface side is an N pole, and the permanent magnets 2b and 2d are magnetized so that the inner peripheral surface side is an S pole. In this embodiment, one magnetic pole is formed by one permanent magnet, but a plurality of divided permanent magnets may be combined to form one magnetic pole.

  A yoke contact surface 11 is formed in the vicinity of the center of the permanent magnet 2 in the circumferential direction (magnetic pole center) on the side of the permanent magnet 2 in contact with the cylindrical yoke 1, and cylindrical at both ends in the circumferential direction of the permanent magnet 2. A notch 12 for separating the yoke 1 is provided. And the four auxiliary yokes 5 (5a-5d) which consist of a magnetic body are installed so that the notch parts 12 which the adjacent permanent magnets 2 face each other may be connected. That is, the auxiliary yoke 5 is provided between the cylindrical yoke 1 and the notch 12 of the permanent magnet 2. The auxiliary yoke 5 is held by a magnet holder 10 (10a to 10f) that is a nonmagnetic elastic body. The magnet holder 10 is provided on the inner peripheral side of the auxiliary yoke 5 and between the adjacent permanent magnets 2. The stator includes a cylindrical yoke 1, a permanent magnet 2, an auxiliary yoke 5, and a magnet holder 10.

  In the present embodiment, the cylindrical yoke 1 and the auxiliary yoke 5 are configured separately. By producing the cylindrical yoke 1 and the auxiliary yoke 5 separately, the workability of each yoke is improved and the productivity of the rotor is increased. The auxiliary yoke 5 may be formed by pressing a single thin plate, or may be formed by laminating thin plates in the axial direction. According to the former processing method, the auxiliary yoke 5 can be manufactured at low cost, and according to the latter processing method, the degree of freedom of shape of the auxiliary yoke 5 can be increased.

  Here, a method of fixing the permanent magnet 2 and the auxiliary yoke 5 will be described. 3 to 6 are development views of parts when the magnet holder 10, the permanent magnet 2, and the auxiliary yoke 5 are assembled. 3 is a perspective view of the magnet holder 10, FIG. 4 is a perspective view of the permanent magnet 2, FIG. 5 is a perspective view of the permanent magnet 2 fixed to the magnet holder 10, and FIG. 6 is a view of fixing the auxiliary yoke 5 to the magnet holder 10. FIG. Between the adjacent permanent magnets 2 as shown in FIG. 4, columnar portions 10a to 10d of a magnet holder 10 formed of a nonmagnetic elastic body such as a resin as shown in FIG. 3 are arranged. In addition, ring-shaped portions 10 e and 10 f of the magnet holder 10 are disposed at both axial ends of the permanent magnet 2 and the auxiliary yoke 5.

  As shown in FIG. 5, the four permanent magnets 2 a to 2 d are arranged in spaces between the columnar portions 10 a to 10 d of the adjacent magnet holders 10. Then, as shown in FIG. 6, the four auxiliary yokes 5 a to 5 d are arranged in a recess 13 constituted by the notch portion 12 of the adjacent permanent magnet 2 and the columnar portions 10 a to 10 d of the magnet holder 10. The outer diameter of the composite body in which the permanent magnet 2, the auxiliary yoke 5, and the magnet holder 10 are integrated is set to be slightly larger than the inner diameter of the cylindrical yoke 1. By press-fitting this composite body into the cylindrical yoke 1, the permanent magnet 2 and the auxiliary yoke 5 are positioned in the axial direction as well as in the circumferential direction, and are formed into a cylindrical shape by the elasticity of the magnet holder 10 which is a nonmagnetic elastic body. It is firmly held in the yoke 1. With this manufacturing method, the auxiliary yoke 5 can be easily and reliably brought into contact with the inner peripheral surface of the cylindrical yoke 1.

  Next, the operating state of the rotating electrical machine will be described taking the motor operation as an example. The commutator 9 provided on the rotor 20 is in contact with the brush 8, and a current flows from the power source (not shown) to the armature winding 7 via the brush 8 and the commutator 9. Torque is generated in the rotor 20 by the interaction between this current and the magnetic field generated by the permanent magnet 2, and the rotating electrical machine operates as a motor.

  The magnetic flux density distribution of the rotating electrical machine during motor operation will be described. FIG. 7 shows the magnetic flux density distribution during motor operation of the rotating electrical machine in the first embodiment, and the shades of color represent the magnetic flux density in each part. On the right side of each figure, the correspondence between color shading and magnetic flux density [unit: T] is shown. In FIG. 7, only a so-called magnetic circuit portion, that is, a cylindrical yoke 1, a permanent magnet 2, a rotor core 3, and an auxiliary yoke 5 are shown. FIG. 8 shows the magnetic flux density distribution in a conventional rotating electrical machine that does not have the auxiliary yoke 5, and the notation is the same as FIG. The permanent magnet 102 of the conventional rotating electrical machine is not provided with notches at both ends in the circumferential direction.

  As shown in FIG. 8, in the conventional rotating electrical machine, it can be seen that the magnetic flux density is very high in the yoke portion near the gap (between the magnetic poles) between the permanent magnets. That is, as a result of the increase in the magnetic resistance of this portion, the amount of magnetic flux interlinking with the rotor cannot be increased, and the torque characteristics for the same current cannot be improved. On the other hand, as shown in FIG. 7, in the present embodiment, the notch portions 12 are provided at both ends in the circumferential direction of the yoke contact surface 11 of the permanent magnet 2, and the auxiliary yoke 5 is disposed here. It can be seen that the magnetic flux density of the cylindrical yoke 1 between the magnetic poles between the permanent magnets 2 is reduced and the magnetic saturation is relaxed.

  How much the torque characteristic is improved by the rotating electrical machine of the present embodiment will be described. FIG. 9 shows a torque waveform with respect to the rotation angle of the rotor 20. The horizontal axis represents the rotation angle (mechanical angle), and the vertical axis represents the torque ratio representing the relative value of the torque of the rotating electrical machine according to the first embodiment when the average value of the torque of the conventional rotating electrical machine is 1. In FIG. 9, the solid line (thin line) is the characteristic of the conventional rotating electric machine, and the solid line (thick line) is the characteristic of the rotating electric machine of the present embodiment. Compared with the conventional rotating electrical machine, the rotating electrical machine of the present embodiment improves the average torque by about 10% with the same current, and further reduces the torque pulsation.

  In the present embodiment, since the thickness of the cylindrical yoke 1 is constant in the circumferential direction, it can be formed by drawing or the like from a plate material with an equal thickness, compared to the case where the yoke is formed of a laminate. It is possible to obtain a yoke with a small number of parts, excellent waterproof and dustproof properties, low cost and good dimensional accuracy. Further, since the thickness of the auxiliary yoke 5 is substantially constant, it is only necessary to curve the plate material in accordance with the curvature of the inner peripheral surface of the cylindrical yoke 1, and it can be formed at a low cost. Further, since the magnet holder 10 made of a non-magnetic elastic material such as resin is used for fixing the auxiliary yoke 5, it is not necessary to provide a holding member or a fixing process (welding or the like) separately from the magnet holding member, and the number of parts is reduced. There are few and it can hold | maintain cheaply.

  As described above, the notch portions 12 are provided at both circumferential ends of the yoke contact surface 11 of the permanent magnet 2 with the cylindrical yoke 1, and the auxiliary yoke 5 is disposed here. The magnetic saturation at the magnetic pole portion can be relaxed, and the torque characteristics can be improved. In addition, since the auxiliary yoke 5 is provided on the inner peripheral surface side of the cylindrical yoke 1, a small and high-performance rotating electrical machine can be obtained. Furthermore, since the cylindrical yoke 1 and the auxiliary yoke 5 have a constant thickness, they can be formed only by pressing or drawing the thin plate, and can be manufactured at low cost.

  In the present embodiment, a four-pole rotating electric machine provided with four permanent magnets 2 has been described. However, the same effect can be obtained in rotating electric machines having different numbers of poles such as six poles and eight poles. Further, it is desirable that the cylindrical yoke 1 and the auxiliary yoke 5 are in close contact as shown in FIG. However, it is more desirable that the cylindrical yoke 1 is in close contact with the permanent magnet 2 as shown in FIG. 10, and a gap 14 is formed between the cylindrical yoke 1 and the auxiliary yoke 5 between the magnetic poles. However, the performance as a motor is not particularly inferior.

Embodiment 2. FIG.
FIG. 11 is a cross-sectional view seen from the axial direction of the rotating electrical machine in the second embodiment for carrying out the present invention. The rotating electrical machine of the present embodiment is different from that of the first embodiment in the shape of the notches at both ends in the circumferential direction of the permanent magnet and the shape of the auxiliary yoke. In FIG. 11, the same reference numerals as those in FIG. 1 denote the same or corresponding parts, and this is common throughout the entire specification. Moreover, the aspect of the component which appears in the whole specification is an illustration to the last, and is not limited to these description. FIG. 12 shows the magnetic flux density distribution during motor operation of the rotating electrical machine.

  As shown in FIG. 11, in the present embodiment, the shape of the auxiliary yoke 25 is thick at the center in the circumferential direction of the permanent magnet 22 (magnetic pole center), and goes toward the adjacent permanent magnet 22 (intermagnetic pole). It is formed so as to become thinner. That is, the auxiliary yoke 25 is formed so as to become thinner toward the circumferential end. The notch 32 of the permanent magnet 22 is configured with only one cross section without providing a step.

  With such a configuration, the weight of the auxiliary yoke 25 can be reduced, and the rotating electrical machine can be reduced in weight. Further, when the cutout portion 32 of the permanent magnet 22 is processed, cracks due to polishing processing are less likely to occur, and the yield at the time of manufacturing the permanent magnet 22 is improved. As a result, the unit price of the permanent magnet 22 is reduced. Become. Further, it is possible to prevent a decrease in reliability due to the crack of the permanent magnet 22. In the processing of the auxiliary yoke 25, processing for forming a shape with a non-uniform plate thickness is required. In the present embodiment, for example, the case where the auxiliary yoke 25 is made from one plate is shown. The thickness is reduced at both ends by pressing or the like. Here, if the end portion of the auxiliary yoke 25 is made too thin, the strength of the end portion becomes weak. Therefore, in the present embodiment, the thickness of the end portion of the auxiliary yoke 25 is the central portion in the circumferential direction of the auxiliary yoke 25. The thickness is about half of the thickness. For this reason, a space is formed between the cylindrical yoke 1 having a curvature, the auxiliary yoke 25, and the permanent magnet 22, although it is very small.

  Also in the rotating electrical machine having such a configuration, as shown in FIG. 12, the notch portions 32 are provided at both ends in the circumferential direction on the yoke contact surface of the permanent magnet 22, and the auxiliary yoke 25 is disposed here. It can be seen that the magnetic flux density of the cylindrical yoke 1 in the portion between the magnetic poles 22 is lowered and the magnetic saturation is relaxed. As in the first embodiment, the average torque is improved by about 10% at the same current as in the first embodiment, and the magnetic saturation in the yoke is not increased without increasing the size of the rotary electric machine. Torque characteristics can be improved by relaxing

Embodiment 3 FIG.
FIG. 13 is a cross-sectional view as seen from the axial direction of the rotating electrical machine in the third embodiment for carrying out the present invention. FIG. 14 is a perspective view of the auxiliary yoke. The rotating electrical machine of the present embodiment is different from the second embodiment in the type of auxiliary yoke. In the present embodiment, the auxiliary yoke 26 is formed of a thin laminated body, and the cylindrical yoke 1 and the auxiliary yoke 26 are fixed by welding. A welded portion 27 is a welded portion between the cylindrical yoke 1 and the auxiliary yoke 26. In the present embodiment, there are two welded portions 27 in the circumferential direction for each auxiliary yoke 26. As a manufacturing method of the auxiliary yoke 26, for example, punching and stacking are performed using a progressive die.

  According to such a configuration, the degree of adhesion between the inner peripheral surface of the cylindrical yoke 1 and the inner peripheral surface of the auxiliary yoke 26 can be increased. Further, when the thickness of the auxiliary yoke 26 is not constant, and when it is desired to further complicate the cross-sectional shape of the auxiliary yoke 26 for the purpose of reducing torque pulsation, the auxiliary yoke 26 having a desired shape can be processed with high accuracy. it can. Furthermore, since the cylindrical yoke 1 and the auxiliary yoke 26 are fixed by welding, there is no possibility that the magnetic resistance increases due to a gap generated between them. Further, there is no risk of noise due to the relative vibration of the cylindrical yoke 1 and the auxiliary yoke 26, and a highly reliable rotating electrical machine can be obtained.

Embodiment 4 FIG.
FIG. 15 is a cross-sectional view seen from the axial direction of the rotating electrical machine in the fourth embodiment for carrying out the present invention. 16 is an enlarged view of a main part of the rotating electrical machine centering on the auxiliary yoke of FIG. 15, and FIG. 17 is a perspective view of the auxiliary yoke. The rotating electric machine according to the present embodiment is different from the first embodiment in that a cylindrical yoke and an auxiliary yoke are fixed by so-called projection welding.

  The auxiliary yoke 45 is provided with a projection 46 in advance, and an electrode is provided between the cylindrical yoke 1 and the auxiliary yoke 45 so that the projection is in contact with the cylindrical yoke 1 and energized. Joule heat is generated in the protrusion 46 and the protrusion 46 is melted to join them together. According to such a configuration, compared to the case where the cylindrical yoke 1 and the auxiliary yoke 45 are fixed only by the columnar portions 10 a to 10 d of the magnet holder 10, the joint force between them can be remarkably improved. It should be noted that the protrusions may be provided on the cylindrical yoke 1, or similar effects can be obtained by providing the protrusions on both the cylindrical yoke 1 and the auxiliary yoke 45.

Embodiment 5 FIG.
FIG. 18 is a cross sectional view seen from the axial direction of the rotating electrical machine in the fifth embodiment for carrying out the present invention. FIG. 19 is a perspective view of the leaf spring. The rotating electric machine according to the present embodiment is different from the fourth embodiment in that a leaf spring is used as a fixing member for the permanent magnet 2 instead of a magnet holder made of a nonmagnetic elastic material such as resin.

  The leaf spring 51 is provided on the inner peripheral side of the auxiliary yoke 45 and between the adjacent permanent magnets 2. The leaf spring 51 of the present embodiment is particularly strong in the circumferential direction. For this reason, by arranging the leaf springs 51 and the permanent magnets 2 alternately so as to go around the axis, the permanent magnets 2 are pressed against the leaf springs 51 in the circumferential direction and fixed. The auxiliary yoke 45 is provided with a projection 46 in advance as in the auxiliary yoke 45 in the fourth embodiment. Further, a second protrusion 52 is also provided on the leaf spring 51 at a position corresponding to the protrusion 46 of the auxiliary yoke 45. The second protrusion may be provided on the auxiliary yoke 45, or the same effect can be obtained by providing the second protrusion on both the leaf spring 51 and the auxiliary yoke 45. The cylindrical yoke 1, the auxiliary yoke 45, and the leaf spring 51 are simultaneously fixed by projection welding. Magnet pressers 53 are formed at both axial ends of the leaf spring 51 to prevent the permanent magnet 2 from moving in the axial direction.

  With such a configuration, it is possible to prevent a gap from being generated between the cylindrical yoke 1 and the auxiliary yoke 45 and thereby reducing the performance of the rotating electrical machine. In addition, since the cylindrical yoke 1 and the permanent magnet 2 are fixed by the leaf spring 51 instead of the magnet holder made of resin or the like, a rotating electric machine that is inexpensive and excellent in heat resistance can be obtained.

Embodiment 6 FIG.
FIG. 20 is a cross sectional view of the stator according to the sixth embodiment for carrying out the present invention. FIG. 21 is a perspective view of a leaf spring. The rotating electric machine according to the present embodiment is different from the fifth embodiment in that the auxiliary yoke is pressed against the cylindrical yoke by a plate spring and fixed.

  The leaf spring 54 is provided on the inner peripheral side of the auxiliary yoke 45 and between adjacent permanent magnets (not shown). The leaf spring 54 according to the present embodiment has a joint portion 55 that protrudes to the outer peripheral side at both end portions in the axial direction. The plate spring 54 is fixed by projection welding the joint 55 and the inner peripheral surface of the cylindrical yoke 1. The leaf spring 54 has elasticity in the circumferential direction as described in the fifth embodiment, and has strong elasticity toward the outer periphery. Therefore, the auxiliary yoke 45 is pressed against the leaf spring 54 on the outer peripheral side, and is pressed and fixed by the cylindrical yoke 1. Further, by arranging the leaf springs 54 and the permanent magnets alternately so as to make a round around the shaft, the permanent magnets are pressed against the leaf springs 54 in the circumferential direction and fixed. As shown in FIG. 20, the second spring 52 is provided on the leaf spring 54 as in the fifth embodiment, and in addition to joining the leaf spring 54 and the cylindrical yoke 1, the leaf spring 54 is provided. And the auxiliary yoke 45 may be joined.

  With such a configuration, it is possible to prevent a gap from being generated between the cylindrical yoke 1 and the auxiliary yoke 45 and thereby reducing the performance of the rotating electrical machine. Further, since the cylindrical yoke 1, the permanent magnet, and the auxiliary yoke 45 are fixed by the plate spring 54 instead of the magnet holder made of resin or the like, a rotary electric machine that is inexpensive and excellent in heat resistance can be obtained.

Embodiment 7 FIG.
FIG. 22 is a cross-sectional view as seen from the axial direction of the rotating electrical machine in the seventh embodiment for carrying out the present invention. The rotating electric machine according to the present embodiment is different from the first embodiment in that an integral yoke is used instead of the cylindrical yoke and the auxiliary yoke. With such a configuration, there is no possibility that the characteristics are deteriorated due to a gap generated between the cylindrical yoke and the auxiliary yoke, and a high-performance motor can be obtained. As a method of forming the integrated yoke 61, it may be formed of a laminated body of thin plates, or may be formed by drawing from a thick plate.

It is sectional drawing of the rotary electric machine in Embodiment 1 of this invention. It is a cross-sectional view of the rotary electric machine in Embodiment 1 of this invention. It is a perspective view of the magnet holder in Embodiment 1 of this invention. It is a perspective view of the permanent magnet in Embodiment 1 of this invention. It is a perspective view of the state where the permanent magnet was fixed to the magnet holder in Embodiment 1 of this invention. It is a perspective view of the state which fixed the auxiliary yoke to the magnet holder in Embodiment 1 of this invention. It is a figure showing magnetic flux density distribution at the time of the motor operation | movement of the rotary electric machine in Embodiment 1 of this invention. It is a figure showing magnetic flux density distribution at the time of motor operation of the conventional rotary electric machine. It is the figure which showed the torque waveform with respect to the rotation angle in Embodiment 1 of this invention. It is sectional drawing which shows the other structure of the rotary electric machine in Embodiment 1 of this invention. It is sectional drawing of the rotary electric machine in Embodiment 2 of this invention. It is a figure showing magnetic flux density distribution at the time of the motor operation | movement of the rotary electric machine in Embodiment 2 of this invention. It is sectional drawing of the rotary electric machine in Embodiment 3 of this invention. It is a perspective view of the auxiliary yoke in Embodiment 3 of this invention. It is sectional drawing of the rotary electric machine in Embodiment 4 of this invention. It is a principal part enlarged view of the rotary electric machine shown in FIG. It is a perspective view of the auxiliary yoke in Embodiment 4 of this invention. It is sectional drawing of the rotary electric machine in Embodiment 5 of this invention. It is a perspective view of the leaf | plate spring in Embodiment 5 of this invention. It is a cross-sectional view of the stator in Embodiment 6 of this invention. It is a perspective view of the leaf | plate spring in Embodiment 6 of this invention. It is sectional drawing of the rotary electric machine in Embodiment 7 of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Cylindrical yoke, 2,22 Permanent magnet, 3 Rotor core, 4 Rotating shaft, 5, 25, 26, 45 Auxiliary yoke, 6 slots, 7 Armature winding, 8 Brush, 9 Commutator, 10 Magnet holder , 11 York contact surface, 12, 32 notch, 13 recess, 14 gap, 20 rotor, 27 welded portion, 46 protruding portion, 51, 54 leaf spring, 52 second protruding portion, 53 magnet presser, 55 Junction, 61 Integrated yoke.

Claims (14)

A cylindrical yoke,
The cylindrical yoke is in contact with the cylindrical yoke at the center in the circumferential direction, a notch for separating the cylindrical yoke from the circumferential end is formed, and a gap is formed between the cylindrical yokes in the circumferential direction. A plurality of arc-shaped permanent magnets provided on the inner peripheral surface;
A rotating electric machine comprising: a stator having the cylindrical yoke and an auxiliary yoke provided between the notches so as to connect the notches facing each other of the adjacent permanent magnets. . The rotating electrical machine according to claim 1, wherein the cylindrical yoke and the auxiliary yoke are formed separately. The rotating electrical machine according to claim 1 or 2, wherein the auxiliary yoke is formed by pressing one thin plate. The rotating electrical machine according to claim 1, wherein the auxiliary yoke is formed by laminating thin plates in the axial direction. The stator has a leaf spring on the inner peripheral side of the auxiliary yoke and between the adjacent permanent magnets,
5. The auxiliary yoke and the leaf spring are fixed by melting a protrusion provided on at least one of the auxiliary yoke and the leaf spring. The rotating electrical machine described in 1. The stator has a leaf spring on the inner peripheral side of the auxiliary yoke and between the adjacent permanent magnets,
5. The rotating electrical machine according to claim 1, wherein the leaf spring is fixed to the cylindrical yoke by a joint that protrudes toward an outer peripheral side at both end portions in the axial direction. The rotating electrical machine according to any one of claims 1 to 6, wherein the auxiliary yoke is fixed to an inner peripheral surface of the cylindrical yoke by welding. 8. The cylindrical yoke and the auxiliary yoke are fixed by melting a protrusion provided on at least one of the cylindrical yoke and the auxiliary yoke. Rotating electric machine. The stator has a nonmagnetic elastic body on the inner peripheral side of the auxiliary yoke and between the adjacent permanent magnets,
The permanent magnet, the auxiliary yoke, and the nonmagnetic elastic body are integrated and press-fitted into the cylindrical yoke, and the permanent magnet and the auxiliary yoke are inside the cylindrical yoke by the elasticity of the nonmagnetic elastic body. The rotating electrical machine according to any one of claims 1 to 4, wherein the rotating electrical machine is fixed to a peripheral surface. The rotating electrical machine according to claim 1, wherein the cylindrical yoke and the auxiliary yoke are integrally formed. The rotating electrical machine according to claim 1, wherein the auxiliary yoke has a substantially constant thickness. 11. The rotating electrical machine according to claim 1, wherein the auxiliary yoke has a thickness that is thick at a center in a circumferential direction and is thinned toward an end in the circumferential direction. The rotating electrical machine according to any one of claims 1 to 12, wherein the cylindrical yoke is formed by drawing a plate material. The rotating electric machine according to any one of claims 1 to 13, wherein the permanent magnet is formed by combining divided permanent magnets.

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