JP7302408B2 - Rotor and rotary machine - Google Patents

Description

The present invention relates to rotors and rotating machines.

Conventionally, the following interior permanent magnet (IPM) rotor is known. That is, a rotor core that rotates around the rotation axis, a plurality of magnets that are held inside the rotor core in a manner aligned in the circumferential direction around the rotation axis, and a rotor core that covers the rotor core from the outside in the radial direction around the rotation axis. and a cover member.

For example, the rotor described in Patent Document 1 includes a rotor core, four permanent magnets held inside the rotor core in a manner arranged in a circumferential direction around the rotation axis, and radially outward around the rotation axis. and a reinforcing member that is a covering member that covers the rotor core. The reinforcing member is made of an annular non-magnetic material. According to Patent Document 1, in such a rotor, the non-magnetic annular reinforcing member can give the rotor the strength to withstand a large centrifugal force during high-speed rotation.

Japanese Patent Application Laid-Open No. 2002-101585

However, when the rotor described in Patent Document 1 is mounted on a rotating machine such as a motor, a reinforcing member is interposed between the rotor and the stator in the radial direction. The structure keeps the permanent magnet away from the stator. In such a structure, since the permanent magnets are moved away from the stator, the density of the magnetic flux extending from the permanent magnets to the stator is reduced, so there is a problem that the rotational characteristics (especially torque) of the motor are reduced.

SUMMARY OF THE INVENTION The present invention has been made in view of the background described above, and an object of the present invention is to provide a rotor and a rotating machine as described below. That is, interposing a covering member such as a reinforcing member between the magnet held inside the rotor core and the stator of the rotating machine suppresses deterioration of the rotation characteristics of the rotor, and increases the strength of the rotor by the covering member. It is a rotor and rotating machine that can

According to one aspect of the present invention, a rotor core that rotates about a rotation axis, a plurality of magnets that are held inside the rotor core in a manner arranged in a circumferential direction about the rotation axis, and a magnet that rotates in a radial direction about the rotation axis. and a cover member covering the rotor core from the outside of the rotor, wherein the cover member includes a plurality of magnetic portions and non-magnetic portions arranged alternately in the circumferential direction, and each of the plurality of magnetic portions includes: Each of the plurality of magnets is individually opposed to each of the plurality of magnets through a wall of the rotor core in a radial direction about the rotation axis, and each of the plurality of nonmagnetic portions is located in the entire circumferential direction of the rotor core. a resin film facing a region between the adjacent magnets along the radial direction and covering an outer peripheral surface of the cover member from the outside in the radial direction, the cover member being attached to the rotor core; The magnetic part of the cover member is composed of a laminated body of wound carbon fiber reinforced resin sheets, and the magnetic part of the cover member is composed of carbon fibers and a thermosetting material impregnated with the carbon fibers in the entire longitudinal direction of the carbon fiber reinforced resin sheet. A magnetic region comprising a resin and ferromagnetic powder particles dispersed in the thermosetting resin is laminated in the radial direction, and the non-magnetic portion of the cover member is the carbon fiber reinforced resin sheet. A non-magnetic region comprising carbon fibers, a thermosetting resin impregnated in the carbon fibers, and non-magnetic powder particles dispersed in the thermosetting resin is laminated in the radial direction in the entire area in the longitudinal direction. It is a thing, a rotor.

Another aspect of the present invention includes a rotor that rotates about a rotation axis, a shaft that penetrates the center of the rotor, and a stator that surrounds the rotor in a circumferential direction about the rotation axis. The rotating machine includes a rotating machine, wherein the rotor is a rotor according to one aspect of the present invention.

According to the present invention, by interposing a cover member such as a reinforcing member between the magnets held inside the rotor core and the stator, deterioration in rotation characteristics of the rotor can be suppressed, and the strength of the rotor can be increased by the cover member. There is an excellent effect of being able to

It is an exploded perspective view showing a motor concerning an embodiment. FIG. 3 is a cross-sectional view showing a cross section in a direction perpendicular to the rotation axis direction of the rotor of the motor; 3 is an enlarged cross-sectional view showing an enlarged part of the cross section of FIG. 2; FIG. FIG. 4 is a perspective view showing a carbon fiber roll in which a carbon fiber sheet, which is a precursor of a cover member of the same rotor, is wound around a bobbin; 1 is a schematic configuration diagram showing a winding device for winding a carbon fiber sheet around a rotor core; FIG. It is an enlarged block diagram which expands and shows a one part structure of the same winding apparatus. FIG. 4 is a cross-sectional view showing a cross section of the rotor core while the carbon fiber sheet is being wound; 1 is a perspective view showing a rotor core of a motor according to a first embodiment; FIG. FIG. 4 is an enlarged cross-sectional view showing particles 90 dispersed in a resin of a magnetic resin material. FIG. 10 is a cross-sectional view showing a further enlarged portion of the cross-section of FIG. 9; FIG. 1 consists of electron micrographs of the surface of iron particles before chemical etching. FIG. 3 consists of electron micrographs of the surface of a chemically etched matrix. FIG. 9 is a cross-sectional view showing an enlarged surface portion of particles dispersed in a magnetic resin material forming a rotor core of a motor according to a second embodiment; FIG. 11 is a cross-sectional view showing a cross section in a direction perpendicular to the rotation axis direction of the rotor of the motor according to the third embodiment;

An embodiment of a motor as a rotating machine to which the present invention is applied will be described below with reference to the drawings. It should be noted that in each figure, illustration of the field winding (coil) wound around the stator core is omitted for convenience.

FIG. 1 is an exploded perspective view showing a motor 1 according to an embodiment. A motor 1 is an IPM type motor and includes a cylindrical housing 2 , a front cover 3 , a rear cover 4 , a shaft 5 , a connector 6 , a rotor 10 and a stator 30 .

The axial shaft 5 passes through a shaft hole (11b in FIG. 2, which will be described later) of the rotor core 11 of the cylindrical rotor 10 in the direction of the rotation axis A, and is positioned on the rotation axis A of the rotor 10. As shown in FIG. The shaft 5 is rotationally driven around the rotational axis A together with the rotor 10 . The cylindrical housing 2 serves as a yoke and holds a cylindrical stator 30 on its inner peripheral surface. The housing 2 has openings at both ends in the rotation axis A direction. The rotor 10 is housed inside a hollow space of a stator 30 held on the inner peripheral surface of the housing 2 .

A bottomed cylindrical front cover 3 is connected to the front side of the housing 2 with the bottom facing the front side. With this connection, the front cover 3 causes the front side of the shaft 5 to pass through the shaft hole 3c provided in the bottom, and closes the front side opening of the housing 2 in the direction of the rotational axis A. As shown in FIG.

The cylindrical stator 30 has a plurality of teeth on its inner peripheral surface arranged at predetermined intervals in the circumferential direction around the rotation axis A, and accommodates the rotor 10 in a hollow space.

The rear cover 4 is fixed to the rear-side end of the housing 2 in the direction of the rotation axis A and closes the rear-side opening of the housing 2 .

The connector 6 protrudes radially outward from a partial region of the outer peripheral surface of the housing 2 at the rear-side end of the housing 2 in the direction of the rotational axis A. As shown in FIG. An external connector is connected to the connector 6 . The external connector is a connector for supplying a three-phase (U-phase, V-phase, W-phase) AC power supply to the motor 1 .

FIG. 2 is a cross-sectional view of the rotor 10 taken in a direction orthogonal to the rotation axis A direction. 3 is an enlarged cross-sectional view showing an enlarged part of the cross section of FIG. 2. FIG. The rotor 10 includes a cylindrical rotor core 11 , eight permanent magnets 12 , a cover member 13 and a resin coating 14 . The rotor core 11 is formed into a cylindrical shape by stacking a plurality of metal plate pieces having a shaft hole 11b in the center, which are obtained by stamping a metal plate, in the direction of the rotation axis A. As shown in FIG. An insulating adhesive for reducing eddy current loss is interposed between the individual metal plate pieces forming the rotor core 11, and the individual metal pieces are insulated from each other. A shaft ( 5 in FIG. 1 ) passes through the central shaft hole 11 b of the rotor core 11 .

The rotor core 11 has eight through-holes 11a arranged in a circumferential direction with the rotation axis A as the center. Each of the eight through-holes 11a penetrates the rotor core 11 in the rotation axis A direction. The rotor core 11 individually accommodates the permanent magnets 12 inside each of the eight through holes 11a.

In order to efficiently extend the magnetic flux from the permanent magnets 12 to the stator (30 in FIG. 1), it is desirable to arrange the through-holes 11a and the permanent magnets 12 as radially outwardly as possible in the rotor core 11 . However, in the rotor 10 rotating at high speed, stress is concentrated on the wall of the rotor core 11 (portion between the through hole 11a and the outer circumference of the core) due to the permanent magnets 12 tending to move radially outward due to centrifugal force. In particular, the stress tends to concentrate on the wall portion that abuts on the edge of the permanent magnet 12, and the wall portion may be damaged.

The cylindrical cover member 13 is made of carbon fiber reinforced plastic (CFRP) and covers the rotor core 11 from the outside in the radial direction about the rotation axis A. As shown in FIG. According to such a configuration, by covering the eight permanent magnets 12 with the hard cover member 13, the strength of the rotor 10 can be increased, and breakage of the wall of the rotor core 11 due to the concentration of stress described above can be suppressed.

The outer peripheral surface of the cover member 13 is formed with minute unevenness due to the weaving of carbon fibers or the like. When the rotor 10 rotates at a high speed, the rotor 10 is subjected to a load due to the uneven wind blowing described above, which adversely affects the rotatability of the rotor 10 . Therefore, the rotor 10 according to the embodiment is provided with the resin coating 14 that covers the outer peripheral surface of the cover member 13 from the outside in the radial direction. The resin coating 14 can improve the rotational performance of the rotor 10 by improving the surface smoothness of the outer peripheral surface of the rotor 10 compared to the configuration in which the outer peripheral surface of the cover member 13 is exposed.

Since the resin coating 14 is a film provided to cover minute irregularities formed on the outer peripheral surface of the cover member 13 to improve the surface smoothness of the rotor 10, the thickness of the resin coating 14 is the same as that of the cover member. It may be about the same as the height of the convex portion on the outer peripheral surface of . For example, the thickness of the resin film 14 may be as thin as several to ten and several μm. Therefore, the deterioration in rotational performance of the rotor 10 due to interposing the resin coating 14 between the permanent magnet 12 and the stator (30 in FIG. 1) is very slight.

The cover member 13 includes eight magnetic portions 13a and eight non-magnetic portions 13b that are alternately arranged in the circumferential direction about the rotation axis A. As shown in FIG. Each of the eight magnetic portions 13a has a ferromagnetic property, and faces each of the eight permanent magnets 12 held inside the rotor core 11 along the radial direction. Each of the eight non-magnetic portions 13b has a non-magnetic property, and extends along the radial direction in the region between the permanent magnets 12 adjacent to each other in the entire circumferential region of the rotor core 11. to face each other.

In the motor 1 having such a configuration, the distance between the permanent magnet and the inner peripheral surface of the stator (30 in FIG. 1) is increased by the thickness of the cover member 13, as in the motor described in Patent Document 1. However, in the motor 1, the ferromagnetic magnetic portion 13a interposed between the permanent magnet 12 and the inner peripheral surface of the stator promotes extension of the magnetic flux from the surface of the permanent magnet 12 to the inner peripheral surface of the stator. do. In addition, the nonmagnetic nonmagnetic portion 13b interposed between the region between the permanent magnets 12 in the circumferential direction of the rotor core 11 and the inner peripheral surface of the stator suppresses the occurrence of magnetic flux leakage. As a result, the motor 1 has the following effects. That is, unlike the rotor described in Patent Document 1 in which the rotor core 11 is covered with a reinforcing member (cover member) made of a non-magnetic material, the cover member 13 is interposed between the permanent magnet 12 and the inner peripheral surface of the stator. It is possible to suppress the deterioration of the rotation characteristics of the motor 1 due to Furthermore, according to the motor 1 , the strength of the rotor 10 can be increased by covering the rotor core 11 with the hard covering member 13 . The magnetic flux leakage is that the magnetic flux extending from the permanent magnet 12 toward the inner peripheral surface of the stator returns toward the rotor core 11 before reaching the inner peripheral surface of the stator, and the permanent magnet 12 of the rotor core 11 is held. This is a phenomenon in which the

FIG. 4 is a perspective view showing the carbon fiber roll 15 in which the carbon fiber sheet 13c, which is the precursor of the cover member 13, is wound around the bobbin 16. As shown in FIG. The carbon fiber sheet 13c is a sheet in which carbon fiber bundles are woven. The type of carbon fiber forming the carbon fiber sheet 13c is not particularly limited as long as it functions as a reinforcing material for carbon fiber reinforced resin. Carbon fibers are roughly classified into polyacrylonitrile (PAN)-based carbon fibers and pitch-based carbon fibers depending on the difference in raw materials. Pitch-based carbon fiber has a property of high elasticity, while polyacrylonitrile-based carbon fiber has a property of high tensile modulus. The carbon fiber used for the cover member 13 may be either pitch-based carbon fiber or polyacrylonitrile-based carbon fiber. preferable. The carbon fiber sheet 13c preferably contains carbon fibers having a tensile modulus of elasticity of 150 [Gpa] or more (strand tensile modulus according to JIS R7601 (1986): the same shall apply hereinafter). Further, the tensile modulus of the carbon fiber is more preferably 200 [GPa] or more, still more preferably 450 [GPa] or more, and particularly preferably 600 [GPa] or more.

The carbon fiber reinforced resin forming the covering member 13 contains carbon fibers, thermosetting resin, ferromagnetic powder particles, and non-magnetic powder particles. The amount of carbon fiber per unit area in the carbon fiber reinforced resin is, for example, 30 [g/m ² ] or more, preferably 50 [g/m ² ] or more, more preferably 70 [g/m ² ] or more. is. By setting the lower limit of the amount of carbon fiber to a predetermined amount or more, it is possible to reduce the number of winding turns when forming a carbon fiber reinforced resin prepreg into a cylindrical shape, and improve productivity. Also, the carbon fiber amount may be, for example, 3000 [g/m ² ] or less, preferably 2000 [g/m ² ] or less, more preferably 1000 [g/m ² ] or less. By setting the upper limit of the carbon fiber amount to a predetermined amount or less, it is possible to suppress the generation of voids in the carbon fiber reinforced resin and obtain a uniform carbon fiber reinforced resin.

FIG. 5 is a schematic configuration diagram showing a winding device 100 for winding a carbon fiber sheet 13c around a rotor core 11 holding eight permanent magnets 12 on its outer peripheral surface. The winding device 100 includes a conveying belt 101, a drive roller 102, a tension roller 103, a support roller 104, an attitude correction roller 105, a pressure roller 106, a leveling roller 107, a first ejection nozzle 108, a second ejection nozzle 109, and the like. Prepare. The winding device 100 also includes a first vacuum nozzle 110, a second vacuum nozzle 111, a cleaning discharge nozzle 112, a cleaning vacuum nozzle 113, and the like.

The endless conveying belt 101 is an endless belt body made of a mesh material and has good air permeability. The conveying belt 101 is stretched by a driving roller 102, a tension roller 103, and a supporting roller 104 arranged inside the belt loop, and endlessly moves clockwise in the figure as the driving roller 102 is driven to rotate. do. Of the entire circumferential area of the conveying belt 101, the area between the portion where the belt is wound around the tension roller 103 and the portion where the belt is wound around the support roller 104 moves along the horizontal direction. Hereinafter, the aforementioned area will be referred to as a "horizontal movement area".

The drive roller 102 receives the drive force of a motor (not shown) and rotates in the clockwise direction in the drawing, thereby imparting an endless moving force to the conveyor belt 101 .

The tension roller 103 and the support roller 104 are driven to rotate following the endlessly moving conveyor belt 101 . Further, the tension roller 103 applies tension to the conveying belt 101 by urging the conveying belt 101 from the inner side of the belt loop toward the outer side with the biasing force of the spring.

Posture correcting roller 105 abuts from the outside of the belt loop on the area before contacting driving roller 102 after separating from support roller 104 in the entire circumferential direction of conveying belt 101, and rotates while following the belt loop. Correct the belt posture. By this correction, the belt area immediately after being separated from the support roller 104 assumes a posture of horizontally moving in the opposite direction to the "horizontally moving area". Hereinafter, the aforementioned belt area will be referred to as a "cleaning area".

The pressurizing roller 106 forms a pressurizing nip by coming into contact with the support roller 104 from the outer side of the belt loop in the entire area of the conveying belt 101 in the circumferential direction due to the biasing force of the spring.

The shaft 5 passing through the shaft hole (11b in FIG. 2) of the rotor core 11 is received by the bearing of the winding device 100 and rotates clockwise together with the rotor core 11 under the driving force of a motor (not shown). drive.

The driven shaft 114 of the winding device 100 is fitted in the through hole of the bobbin 16 of the carbon fiber roll 15 . A torque limiter is mounted on the driven shaft 114, and the driven shaft 114 is driven to rotate when a predetermined torque or more is applied.

The carbon fiber sheet 13 c wound around the bobbin 16 is pulled out from the carbon fiber roll 15 and wound around the rotor core 11 after passing through the sheet conveying path. The above-described sheet conveying path is a path that passes through a portion of the conveying belt 101 that is wrapped around the tension roller 103 , a “horizontal movement area”, and a portion that is wrapped around the support roller 104 .

FIG. 6 is an enlarged configuration diagram showing an enlarged configuration of a part of the winding device 100. As shown in FIG. In the carbon fiber sheet 13c, carbon fibers 13d extend in the sheet longitudinal direction (=sheet conveying direction). In the “horizontal movement region” of the transport belt 101, the first ejection nozzle 108 and the second ejection nozzle 109 face each other from above in the direction of gravity. The first ejection nozzle 108 and the second ejection nozzle 109 are arranged along the conveying direction of the carbon fiber sheet 13c. Both the nozzle hole of the first discharge nozzle 108 and the nozzle hole of the second discharge nozzle 109 extend along the sheet width direction of the carbon fiber sheet 13c, and the width direction of the carbon fiber sheet 13c conveyed by the conveying belt 101. It is possible to supply the discharge material to the entire area of .

The tip of the first vacuum nozzle 110 is in contact with the area facing the first ejection nozzle 108 from the inside of the belt loop, out of the entire area of the conveying belt 101 in the circumferential direction. In addition, the second vacuum nozzle 111 is in contact with the area facing the second ejection nozzle 109 from the inner side of the belt loop in the entire area of the conveying belt 101 in the circumferential direction.

A ferromagnetic resin 201 before curing is pumped to the first discharge nozzle 108 . The ferromagnetic resin 201 ejected from the nozzle holes of the first ejection nozzle 108 is supplied to the carbon fiber sheet 13c that moves horizontally while being held in the "horizontal movement area" of the conveyor belt 101, and the mesh of the conveyor belt 101 is supplied to the carbon fiber sheet 13c. The air is sucked into the first vacuum nozzle 110 through the air. By this suction, the uncured ferromagnetic resin 201 supplied to the carbon fiber sheet 13c permeates the carbon fiber sheet 13c along the sheet thickness direction.

The non-magnetic resin 202 before curing is pumped to the second discharge nozzle 109 . The non-magnetic resin 202 ejected from the nozzle holes of the second ejection nozzle 109 is supplied to the carbon fiber sheet 13c that is conveyed while being held in the “horizontal movement area” of the conveying belt 101, and passes through the mesh of the conveying belt 101. It is sucked by the second vacuum nozzle 111 . Due to this suction, the uncured non-magnetic resin 202 supplied to the carbon fiber sheet 13c permeates the carbon fiber sheet 13c along the sheet thickness direction.

The ferromagnetic resin 201 ejected from the first ejection nozzle 108 comprises a thermosetting resin (thermoplastic resin) and ferromagnetic powder particles dispersed in the thermosetting resin. A thermosetting resin includes a base material resin, a curing agent, and a silane coupling agent. As the base material resin, it is possible to use epoxy resin, phenol resin, or the like. It is desirable to select

As the epoxy resin, a diglycyl ether type epoxy resin is preferable, but a diglycylamine type, diglycyl ester type, or olefin oxidation (alicyclic) type epoxy resin may also be used. Specific examples include bisphenol A-type epoxy resin, bisphenol F-type epoxy resin, bisphenol S-type epoxy resin, phenolborac-type epoxy resin, cresol novolac-type epoxy resin, resorcinol-type epoxy resin, epoxy resin having a naphthalene skeleton, and the like. be done. There are no particular restrictions on the epoxy equivalent.

The curing agent may be of any type capable of curing the epoxy resin. Examples of curing agents include amine-based curing agents, acid anhydride-based curing agents, and phenol-based curing agents. Among these, amine-based curing agents are preferred, and dicyandiamide and diaminodiphenylsulfone are more preferred. The content of the curing agent is not particularly limited as long as it can supply at least the amount of bondable functional groups calculated from the epoxy equivalent.

Materials for the ferromagnetic powder particles include iron, cobalt, nickel, alloys thereof, and ferrite, all of which have ferromagnetic properties.

The viscosity of the ferromagnetic resin 201 and the non-magnetic resin 202 at 50° C. is preferably 10 Pa·s or more, more preferably 50 Pa·s or more. Since the lower limit value of the viscosity is equal to or higher than the predetermined value, dripping of the ferromagnetic resin 201 and the non-magnetic resin 201 can be suppressed, and resin diffusion in the sheet surface direction can be suppressed.

The viscosity of the ferromagnetic resin 201 and the non-magnetic resin 202 at 50° C. is preferably 20000 [Pa·s] or less, more preferably 10000 [Pa·s] or less. By setting the upper limit of the viscosity to a predetermined value or less, the tackiness (adhesiveness) and drapeability (flexibility) of the ferromagnetic resin 201 and the non-magnetic resin 202 can be further improved.

The non-magnetic resin 202 ejected from the second ejection nozzle 109 comprises a thermosetting resin and non-magnetic powder particles dispersed in the thermosetting resin. As the thermosetting resin, the same material as the ferromagnetic resin 201 can be used. As the material of the non-magnetic powder particles, it is desirable to use a non-magnetic metal such as stainless steel, and more specifically, a non-magnetic metal having a higher specific gravity than the thermosetting resin is desirable. By dispersing non-magnetic powder particles made of a non-magnetic metal having a higher specific gravity than the thermosetting resin in the thermosetting resin, the specific gravity of the non-magnetic portion 13b can be increased to the same level as the specific gravity of the magnetic portion 13a. It is possible. In such a configuration, due to the difference in specific gravity between the magnetic portion 13a and the non-magnetic portion 13b, the magnetic portion 13a is subjected to a centrifugal force stronger than that of the non-magnetic portion 13b during high-speed rotation. The occurrence of plastic deformation can be suppressed.

In FIG. 5 , the carbon fiber sheet 13 c conveyed while being held in the “horizontal movement area” of the conveying belt 101 passes through the position facing the second discharge nozzle 109 , and then moves between the conveying belt 101 and the pressure roller 106 . It enters the pressure nip, which is the contact portion, and is pressed in the thickness direction. After passing through the pressure nip, the carbon fiber sheet 13c is separated from the conveying belt 101 and the pressure roller 106, and then wound around the rotor core 11 and the permanent magnet 12 that rotate clockwise in the drawing. At this time, the carbon fibers are wound so as to extend in the circumferential direction of the rotor core 11 .

In the winding device 100, the driving speed of the driving roller 102 and the driving of the rotor core 11 are adjusted so that the linear speed of the permanent magnet 12 on the outer peripheral surface of the rotor core 11 that is rotationally driven and the linear speed of the conveying belt 101 are equal. speed is adjusted.

The carbon fiber sheet 13c is cut at a position where it is wound around the rotor core 11 by a predetermined number of turns in the sheet longitudinal direction. The carbon fiber sheet 13c wound around the rotor core 11 is pressed by the leveling roller 107 to remove wrinkles.

A thermoplastic resin adheres to the conveying belt 101 that has passed through the pressure nip, which is the contact portion with the pressure roller 106 . The transport belt 101 is cleaned in the "cleaning area" to remove the thermoplastic resin. In the “cleaning area”, the cleaning liquid discharged from the cleaning ejection nozzles 112 is sucked by the cleaning vacuum nozzles 113 through the conveyor belt 101 in the thickness direction of the conveyor belt 101, thereby passing through the conveyor belt 101 in the thickness direction. to wash out the thermoplastic resin.

FIG. 7 is a cross-sectional view showing a cross section of the rotor core 11 while the carbon fiber sheet 13c is being wound. The carbon fiber sheet 13c immediately before being wound around the rotor core 11 has a plurality of magnetic regions 13e and non-magnetic regions 13f that are alternately arranged along the longitudinal direction of the sheet. The magnetic region 13e is impregnated with the ferromagnetic resin 201 described above. The nonmagnetic region 13f is impregnated with the nonmagnetic resin 202 described above. Both the ferromagnetic region 13e and the non-magnetic region 13f are carbon fiber reinforced resin prepregs containing thermosetting resin before curing.

The carbon fiber sheet 13c is wound around the rotor core 11 over a plurality of turns. As a result, a plurality of carbon fiber sheets 13 c are laminated on the rotor core 11 along the radial direction of the rotor core 11 . On the outer peripheral surface of the rotor core 11 , the first layer of the carbon fiber sheet 13 c brings the ferromagnetic region 13 e into close contact with the region facing the permanent magnet 12 . In the first layer, the non-magnetic region 13f is radially opposed to the region between the permanent magnets 12 in the entire circumferential region of the rotor core 11 . In the second and subsequent layers of the carbon fiber sheet 13c, the ferromagnetic region 13e is brought into close contact with the ferromagnetic region 13e of the layer one layer below, and the non-magnetic region 13f is brought into close contact with the non-magnetic region 13f of the layer one below. Let Hereinafter, in the laminated structure of the carbon fiber sheet 13c being wound, among the upper and lower layers adjacent to each other in the sheet thickness direction, the upper layer is referred to as the "adjacent upper layer" and the lower layer is referred to as the "adjacent lower layer".

As the carbon fiber sheet 13c is wound around the rotor core 11 in a plurality of layers, the outer diameter of the wound body made of the carbon fiber sheet 13c gradually increases. Even with such an increase in outer diameter, most of the ferromagnetic region 13e of the "adjacent upper layer" of the carbon fiber sheet 13c in the circumferential direction does not adhere to the non-magnetic region 13f of the "adjacent lower layer". It adheres only to the ferromagnetic region 13e of the "adjacent lower layer". In addition, most of the circumferential direction of the non-magnetic region 13f of the "adjacent upper layer" of the carbon fiber sheet 13c does not adhere to the ferromagnetic region 13e of the "adjacent lower layer", but only the non-magnetic region 13f of the "adjacent lower layer". In close contact. That is, in the laminated structure of the carbon fiber sheets 13c, most of the ferromagnetic region 13e of the "adjacent upper layer" in the circumferential direction is in close contact only with the ferromagnetic region 13e of the "adjacent lower layer", and the non-magnetic region of the "adjacent upper layer" Most of the circumferential portion of 13f adheres only to the non-magnetic region 13f of the "adjacent lower layer". The winding device 100 adjusts the length of each ferromagnetic region 13e and the length of each non-magnetic region 13f in the sheet length direction so as to achieve the above-described close contact relationship. This adjustment consists of the ejection timing and ejection time of the ferromagnetic resin (201 in FIG. 6) from the first ejection nozzle (108 in FIG. 6) and the ejection time of the non-magnetic resin (109 in FIG. 6) from the second ejection nozzle (109 in FIG. 6-202) by adjusting the combination of ejection timing and ejection time. Only when the ferromagnetic resin is being discharged from the first discharge nozzle, suction is performed by the first vacuum nozzle (110 in FIG. 6), and the non-magnetic resin is discharged from the second discharge nozzle. Suction by the second vacuum nozzle (111 in FIG. 6) takes place only when the

The rotor core 11, on which the carbon fiber sheet 13c containing thermosetting resin is wound a predetermined number of turns, is removed from the winding device 100, set in a heater, and heated at a predetermined temperature for a predetermined period of time. Due to this heating, the carbon fiber sheet 13c wound around the rotor core 11 is sintered and hardened into a hard covering member (13 in FIG. 2).

In FIG. 2, the cross sections of the magnetic portion 13a and the non-magnetic portion 13b of the cover member 13 are hatched differently for the sake of convenience in order to clearly distinguish them from each other. , it is difficult to distinguish between the magnetic portion 13a and the non-magnetic portion 13b by appearance. As a method for determining whether or not a portion of the covering member 13 in the circumferential direction that faces the permanent magnet 12 along the radial direction (hereinafter referred to as a “magnet-facing portion”) is the magnetic portion 13a, A method using fluorescent X-ray analysis is mentioned. Specifically, the elemental composition of the "magnet-facing portion" of the cover member 13 is analyzed by fluorescent X-ray analysis, and if at least one of iron, cobalt, and nickel is detected, the "magnet-facing portion" is detected. can be determined to be the magnetic portion 13a. Another method is a method using atomic absorption spectrometry. In this method, the "magnet-facing portion" of the cover member 13 is pulverized into powder and used as the specimen. Then, the elemental composition in the solution obtained by dissolving the sample is analyzed by atomic absorption spectrometry, and if at least one of iron, cobalt, and nickel is detected, the "magnet facing portion" is the magnetic portion 13a. It is possible to determine that

Of the entire circumferential region of the cover member 13, a portion radially facing a region of the rotor core 11 that does not hold the permanent magnets 12 (hereinafter referred to as a "core-facing portion") is a non-magnetic portion 13b. To determine whether or not, the following should be done. That is, the elemental composition of the "core-facing portion" of the cover member 13 is analyzed by fluorescent X-ray analysis, and if none of iron, cobalt, and nickel are detected (including the case where only a very small amount is detected), the "core-facing portion" is detected. It is possible to determine that the "portion" is the non-magnetic portion 13b. In addition, the “core-facing portion” of the cover member 13 was pulverized into powder as a sample, and the elemental composition of the solution in which the sample was dissolved was analyzed by atomic absorption spectrometry, and based on the presence or absence of iron, cobalt, and nickel , and the “core facing portion” may be determined whether or not it is the non-magnetic portion 13b.

Next, a description will be given of a first example in which a more characteristic configuration is added to the motor 1 according to the embodiment. Note that the configuration of the motor 1 according to the example is the same as that of the embodiment unless otherwise specified.

FIG. 8 is a perspective view showing the rotor core 11 of the motor 1 according to the first embodiment. Comparing the rotor cores 11 of the embodiment and the first example, they have the same shape, but different structures. Specifically, the rotor core 11 according to the embodiment is formed by laminating a plurality of metal plates obtained by punching through an insulating adhesive, whereas the rotor core 11 according to the first embodiment , is formed by molding a magnetic resin material. The magnetic resin material is obtained by dispersing particles whose base is ferromagnetic metal particles (particles made of iron, cobalt, nickel, or alloys thereof) in a resin material. In the first embodiment, iron particles are used as the ferromagnetic metal particles serving as the matrix of the particles dispersed in the resin material.

FIG. 9 is an enlarged sectional view showing particles 90 dispersed in the resin of the magnetic resin material. FIG. 10 is a cross-sectional view showing a part of the cross-section of FIG. 9 further enlarged. In FIG. 9, the hatching of the coating 92, which will be described later, is omitted for easy viewing.

Particle 90 includes a base body 91 made of iron particles and an insulating coating 92 . The particle size of the matrix 91 has a distribution of 10 [μm] to 100 [μm], and the median value is 40 [μm]. The outer shape of the base 91 is polygonal. On the surface of the base body 91, a plurality of plate-like protrusions 91a with a height of 2.0 [μm] to 3.0 [μ] are formed. The flat-plate-like protrusions 91a are formed by chemical etching.

FIG. 11 consists of electron micrographs of the surface of iron particles before chemical etching. As shown in FIG. 11, the surface of the iron particles before chemical etching consists of smooth planes.

FIG. 12 consists of an electron micrograph of the surface of the chemically etched matrix (91). As shown in FIG. 12, a plurality of plate-like projections 91a are formed on the chemically etched surface of the matrix.

Chemical etching is performed as follows. First, in order to impart basic functional groups to the surface of the iron particles, iron powder made up of a collection of iron particles is heat-treated with a non-acidic solution, more specifically a sodium hydroxide solution. Next, by heat-treating (etching) the iron powder with sulfuric acid, it is possible to obtain iron powder composed of a collection of iron particles (base 91) having a plurality of protrusions 91a on their surfaces.

After obtaining the iron powder consisting of the aggregate of the matrix 91, the iron powder is washed sufficiently with pure water or the like, and then the iron powder and SiCl ₄ are reacted at a high temperature to give the surface of the matrix 91 an insulating property. A coating 92 (Fe ₃ Si film) is formed to obtain powder composed of a collection of particles 90 . In FIG. 10, the thickness of the insulating film 92 is 0.1 [μm] to 5.0 [μm].

After obtaining the powder composed of the collection of particles 90, the powder is mixed with a resin added with a silane coupling agent, and the mixture is molded in a metal mold to obtain the rotor core 11. FIG.

In the rotor 10 according to the first embodiment, the particles 90 dispersed in the magnetic resin material forming the rotor core 11 are not in direct contact with the matrix 91 (iron particles), but the insulating coating 92 is interposed. Due to this intervention, it is possible to suppress a decrease in rotational efficiency of the rotor 10 due to eddy current loss.

In the magnetic resin material that constitutes the rotor core 11, the particles 90 having a plurality of flat plate-like projections 91a on their surfaces increase the contact surface with the resin and bite into the resin to produce an anchor effect. Cracks are less likely to occur at the interface with the particles 90 . Therefore, although the rotor core 11 is made of resin, the rotor core 11 can exhibit durability to function properly as a rotor core of the motor 1 (or generator). Moreover, according to the motor 1 , the strength of the rotor 10 can be increased by covering the rotor core 11 with the cover member 13 . Further, according to the motor 1 according to the first embodiment, it is possible to manufacture the rotor core 11 in one simple process of molding with a mold. Therefore, according to the motor 1, the productivity of the rotor 10 can be improved compared to the rotor core 11 according to the embodiment obtained by laminating a plurality of metal pieces obtained by punching with an insulating adhesive. Furthermore, according to the motor 1 according to the first embodiment, compared to the motor 1 according to the embodiment, it is possible to reduce the weight of the rotor 10 and improve the responsiveness of rotation start and rotation stop.

The resin in which the particles 90 are dispersed is a resin that has a functional group substituted on its main chain and that can directly form a covalent bond with a functional group containing an oxygen atom (O). and resins containing maleic anhydride can be exemplified. As for the silane coupling agent described above, one having a functional group corresponding to the type of resin is used. For example, when a bisphenol A type epoxy resin is selected as the resin, a silane coupling agent having an epoxy group as a functional group is used. In addition, the above-mentioned functional group is provided to the terminal of the side chain. For the purpose of impregnating the resin between the protrusions 91a, the viscosity of the resin is desirably 1500 [mPa·s] or less.

The present inventors found that the particles 90 having a plurality of flat plate-shaped projections 91a on the surface are less likely to crack at the interface between the particles 90 and the resin, and have improved strength, compared to particles that do not have the projections 91a. In order to confirm that it can be obtained, the experiment described below was performed.

100 [ml] of 1.5 [%] sodium hydroxide (NaOH) solution, 100 [ml] of 9.8 [%] sulfuric acid (H ₂ SO ₄ ) solution, and 100 [ml] of 3 [%] nitric acid (HNO ₃ ) solution [ml] was prepared. As for granular sodium hydroxide, 1.46 [g] was weighed into a glass beaker, dissolved in pure water, and diluted to a volume of 1.46 [%]. For sulfuric acid, 10 [ml] of a 98 [%] undiluted solution was taken and diluted 10 times with pure water. As for nitric acid, 5 [ml] of a 61 [%] stock solution was taken and then diluted 20 times with pure water to obtain a 3.05 [%] solution. Since it was unknown to what extent the iron particles would dissolve in the solution, the iron powder used in the experiment had an average particle size of 200 [μm]. About 10 [ml] of a sodium hydroxide solution preheated to 40 [°C] was added to about 5 [g] of iron powder, and the mixture was allowed to stand for 1 minute to obtain a reaction solution. Thereafter, the iron powder was separated from the reaction solution by a centrifuge, and ultrapure water was added to the iron powder, followed by ultrasonic cleaning three times or more to obtain an iron powder treated with sodium hydroxide.

The sodium hydroxide-treated iron powder was treated with sulfuric acid without being dried. Specifically, a sulfuric acid solution preheated to about 45° C. was added to iron powder treated with sodium hydroxide. At this time, the sulfuric acid solution foamed violently, but the solution was allowed to stand still for 3 minutes, and then the supernatant was removed. After that, the same washing treatment as the sodium hydroxide treatment was performed three times or more to obtain a sulfuric acid-treated iron powder. The nitric acid treatment was carried out in the same manner as the sulfuric acid treatment, except that a nitric acid solution was used as the solution. The nitric acid solution added to the iron powder foamed, but the amount of foaming was not as large as that of the sulfuric acid treatment. For the nitric acid-treated iron powder, additional washing with acetone is preferred. When the iron powder after additional washing was observed with an optical microscope, no significant change in particle size was observed.

A magnetic resin material was produced using the iron powder after additional washing. Specifically, an epoxy resin (JER828 manufactured by Mitsubishi Chemical Corporation) and methylhimic anhydride (HN-5500 manufactured by Hitachi Chemical Co., Ltd.) were prepared. In addition, tris(dimethylaminomethyl)phenol-tri(2-ethylhexote) and chemically etched iron powder were prepared.
Ankamin K-61B manufactured by Air Products Japan Co., Ltd. was used as 2-ethylhexate. The average particle diameter of chemically etched iron powder is 40 [μm]. Each prepared substance was mixed at a ratio of 10 (JER828):8 (HN5500):0.02 (K61B):95 (iron powder). Then, the mixture was kneaded by a rotation/revolution mixer to obtain a magnetic resin material. Hereinafter, this magnetic resin material will be referred to as a magnetic resin material according to the first embodiment.

ARE310 manufactured by Thinky Co., Ltd. was used as the rotation/revolution mixer. The kneading conditions were as follows: kneading at 2000 [rpm] for 30 seconds and then kneading at 2200 [rpm] for 30 seconds.

A magnetic resin material was obtained in the same manner as the magnetic resin material according to the first embodiment, except that iron powder having an average particle size of 40 [μm] which was not subjected to chemical etching was used. Hereinafter, this magnetic resin material is referred to as a magnetic resin material according to a comparative example.

The bending breaking strength was measured for each of the magnetic resin material according to the first example and the magnetic resin material according to the comparative example. The bending fracture strength of the magnetic resin material according to the comparative example was 88.5 [MPa] (N = 8, σ = 3.5, whereas the bending fracture strength of the magnetic resin material according to the example was 96.1 [MPa]. [MPa] (N = 5, σ = 11.0) According to the results, the magnetic resin material in which the chemically etched particles 90 were dispersed dispersed the particles not chemically etched. It has been confirmed that the strength of the rotor 10 can be increased compared to the magnetic resin material.

Next, a description will be given of a second embodiment in which a more characteristic configuration is added to the motor 1 according to the first embodiment. The configuration of the motor 1 according to the second embodiment is the same as that of the first embodiment, unless otherwise specified.

FIG. 13 is a cross-sectional view showing an enlarged surface portion of particles 90 dispersed in the magnetic resin material that constitutes the rotor core 11 of the motor 1 according to the second embodiment. Regions between adjacent protrusions 91a on the surface of the matrix 91 of the particle 90 are not covered with the insulating film 92, and the surface of the matrix 91 is exposed. In the chemical etching process, as shown in the figure, only the tips of the projections 91a are covered with the film 92, and the surface of the base body 91 is exposed in the region between the projections 91a. It is possible to obtain particles 90 that allow That is, the gas phase reaction method is used to appropriately adjust the reaction time and temperature conditions between SiCl ₄ and iron powder.

Even if the surface of the base body 91 is exposed in the region between the convex parts 91a adjacent to each other, since the tips of the convex parts 91a are covered with the film 92, the base body 91 is not covered with the particles 90. There is no direct contact, and eddy current loss is suppressed. Since the resin material has better adhesion to the base body 91 than the insulating film 92 (Fe ₃ Si film), the occurrence of cracks at the interface between the particles 90 and the resin is better suppressed, and the strength of the rotor 10 is increased. can be higher.

Next, a description will be given of a third embodiment in which a more characteristic configuration is added to the motor 1 according to the first embodiment. The configuration of the motor 1 according to the third embodiment is the same as that of the first embodiment, unless otherwise specified.

FIG. 14 is a cross-sectional view showing a cross section of the rotor 10 of the motor 1 according to the third embodiment in a direction perpendicular to the rotation axis A direction. In this rotor 10, the cross-sectional shape of each of the eight through-holes 11a in the direction orthogonal to the rotation axis A and the cross-sectional shape of each of the eight permanent magnets 12 in the direction orthogonal to the rotation axis A both correspond to the rotation axis. It has an arc shape centered on A.

As is clear from a comparison with FIG. 2, this configuration allows the eight permanent magnets 12 to be brought closer to the outer edge of the rotor core 11 than the configuration having the non-circular through-holes 11a and the permanent magnets 12. , the rotational performance of the rotor 10 can be further improved. The distance between the portion of the through-hole 11a closest to the outer edge of the rotor core 11 and the outer edge of the rotor core 11 is the same as the rotor 10 according to the first embodiment (FIG. 2) and the rotor 10 according to the third embodiment (FIG. 14). ) is the same as Therefore, although the rotor 10 of the motor 1 according to the third embodiment has the permanent magnets 12 closer to the outer edge of the rotor core 11 than in the configuration shown in FIG. The strength of the rotor 10 can be increased to the same level as

Instead of adding the configuration of the motor 1 according to the third embodiment to the motor 1 according to the first embodiment, the configuration of the motor 1 according to the third embodiment may be added to the motor 1 according to the embodiment. is also possible.

Although an example in which the present invention is applied to the motor 1 as a rotating machine has been described, the present invention can also be applied to a generator (dynamo) as a rotating machine.

The present invention is not limited to the above-described embodiments, and configurations different from the embodiments can be employed within the scope of application of the configurations of the present invention. The present invention provides unique effects for each of the aspects described below.

[First aspect]
A first aspect includes a rotor core (for example, rotor core 11) that rotates about a rotation axis (for example, rotation axis A), and a plurality of magnets (for For example, a rotor (for example, a rotor 10) including a permanent magnet 12) and a covering member (for example, a covering member 13) covering the rotor core from the outside in a radial direction about the rotation axis, wherein the covering member A plurality of magnetic portions (e.g., magnetic portions 13a) and non-magnetic portions (e.g., non-magnetic portions 13b) arranged alternately in a direction are provided, and each of the plurality of magnetic portions is aligned with the rotor core in a radial direction about the rotation axis. each of the plurality of magnetic portions is individually opposed to each of the plurality of magnetic portions via a wall, and each of the plurality of non-magnetic portions is located between the magnets adjacent to each other in the entire region of the rotor core in the circumferential direction; along the radial direction.

According to such a configuration, it is possible to suppress deterioration in rotation characteristics of the rotor due to interposition of the cover member between the magnets held inside the rotor core and the stator, and to increase the strength of the rotor by the cover member.

[Second aspect]
A second aspect includes the configuration of the first aspect and a resin coating (for example, a resin coating 14) covering the outer peripheral surface of the cover member from the radially outer side, and the cover member is wound around the rotor core. It consists of a laminate of carbon fiber reinforced resin sheets (for example, a carbon fiber sheet 13c impregnated with a thermosetting resin and baked), and the magnetic portion of the cover member covers the entire length of the carbon fiber reinforced resin sheet. Among them, a magnetic region (for example, a ferromagnetic region 13e) comprising carbon fibers, a thermosetting resin impregnated in the carbon fibers, and ferromagnetic powder particles dispersed in the thermosetting resin is arranged in the radial direction The non-magnetic portion of the cover member is formed by stacking carbon fibers, a thermosetting resin impregnated in the carbon fibers, and the thermosetting resin in the entire longitudinal direction of the carbon fiber reinforced resin sheet. The rotor comprises non-magnetic regions (for example, non-magnetic regions 13f) including non-magnetic powder particles dispersed in a resin, which are laminated in the radial direction.

According to such a configuration, after winding a carbon fiber reinforced plastic prepreg in which the magnetic portion and the nonmagnetic portion are alternately arranged in the longitudinal direction of the sheet before curing the resin, around the rotor core and the magnet, the prepreg is sintered to form a cylinder. A shaped covering member can be formed. Further, according to the second aspect, by increasing the specific gravity of the non-magnetic portion to the same extent as the specific gravity of the magnetic portion, the difference in specific gravity between the magnetic portion and the non-magnetic portion prevents the magnetic portion from rotating at high speed. It is possible to suppress the occurrence of plastic deformation of the cover member by applying a centrifugal force stronger than that of the non-magnetic portion to the non-magnetic portion.

[Third aspect]
A third aspect has the configuration of the first aspect or the second aspect, wherein the rotor core is made of a resin material in which particles (e.g., particles 90) having ferromagnetic metal particles as bases (e.g., bases 91) are dispersed, and the bases are is a rotor provided with a plurality of plate-like protrusions (eg, protrusions 91a) on the surface, and the protrusions are covered with an insulating coating (eg, coating 92).

According to such a configuration, compared to a rotor obtained by laminating a plurality of metal pieces, the productivity of the rotor can be improved, and the responsiveness of starting and stopping rotation can be improved by reducing the weight of the rotor. In addition, the strength of the rotor 10 can be increased as compared with the case of using particles that do not have a plurality of flat plate-like projections on the surface as the particles dispersed in the resin material.

[Fourth aspect]
A fourth aspect is the rotor having the configuration of the third aspect, wherein a region between the convex portions adjacent to each other exposes the surface of the base.

According to such a configuration, it is possible to increase the strength of the rotor as compared with a configuration in which the regions between adjacent protrusions are covered with an insulating film.

[Fifth aspect]
A fifth aspect comprises the configuration of any one of the first to fourth aspects, wherein each of the plurality of magnets has a cross-sectional shape in a direction orthogonal to the rotation axis, which is an arc shape centered on the rotation axis. is the rotor.

According to such a configuration, compared to a configuration in which the cross-sectional shape of the plurality of magnets is not arcuate, the strength of the rotor can be increased to the same level as the same configuration while improving the rotational performance of the rotor.

[Sixth aspect]
A sixth aspect includes a rotor that rotates about a rotation axis, a shaft (e.g., shaft 5) passing through the center of the rotor, and a stator (e.g., stator) that surrounds the rotor along the circumferential direction about the rotation axis. 30), wherein the rotor is the rotor according to any one of the first to fifth aspects.

According to such a configuration, it is possible to suppress deterioration in rotation characteristics of the rotor due to interposition of the cover member between the magnets held inside the rotor core and the stator, and to increase the strength of the rotor by the cover member.

INDUSTRIAL APPLICABILITY The present invention can be applied to rotating machines such as motors and generators.

A: Rotation axis 1: Motor (rotating machine) 2: Housing 3: Front cover 4: Rear cover 5: Shaft 6: Connector 10: Rotor 11: Rotor core 11b: Shaft hole 12: Permanent Magnet (magnet) 13: Cover member 13a: Magnetic part 13b: Non-magnetic part 13c: Carbon fiber sheet 13d: Carbon fiber 13e: Magnetic region 13f: Non-magnetic region 14: Resin coating 15; Carbon fiber roll 16: Bobbin 90: Particles 91: Base 91a: Projection 201: Ferromagnetic resin 202: Non-magnetic resin

Claims (5)

A rotor core that rotates about a rotation axis, a plurality of magnets that are held inside the rotor core in a manner aligned in a circumferential direction about the rotation axis, and a rotor core that covers the rotor core from the outside in a radial direction about the rotation axis. A rotor comprising a cover member,
the cover member includes a plurality of magnetic portions and non-magnetic portions that are alternately arranged in the circumferential direction;
each of the plurality of magnetic portions individually faces each of the plurality of magnets via a wall of the rotor core in a radial direction about the rotation axis;
each of the plurality of non-magnetic portions faces a region between the magnets adjacent to each other in the entire circumferential direction of the rotor core along the radial direction;
a resin coating covering the outer peripheral surface of the covering member from the outside in the radial direction;
the cover member is made of a laminate of carbon fiber reinforced resin sheets wound around the rotor core,
The magnetic portion of the cover member comprises carbon fibers, a thermosetting resin impregnated in the carbon fibers, and ferromagnetism dispersed in the thermosetting resin in the entire longitudinal direction of the carbon fiber reinforced resin sheet. Magnetic regions comprising body powder particles are laminated in the radial direction,
The non-magnetic portion of the cover member comprises carbon fibers, a thermosetting resin impregnated in the carbon fibers, and a non-magnetic portion dispersed in the thermosetting resin in the entire longitudinal direction of the carbon fiber reinforced resin sheet. Non-magnetic regions comprising magnetic powder particles are laminated in the radial direction,
rotor. The rotor core is made of a resin material in which particles having ferromagnetic metal particles as a base are dispersed,
The base has a plurality of flat plate-shaped protrusions on its surface,
The convex portion is covered with an insulating film,
A rotor according to claim 1 . a region between the protrusions exposes the surface of the matrix;
3. A rotor according to claim 2 . A cross-sectional shape of each of the plurality of magnets in a direction orthogonal to the rotation axis is an arc shape centered on the rotation axis,
A rotor according to any one of claims 1 to 3 . A rotating machine comprising a rotor rotating about a rotation axis, a shaft passing through the center of the rotor, and a stator surrounding the rotor in a circumferential direction about the rotation axis,
A rotating machine, wherein the rotor is the rotor according to any one of claims 1 to 4 .

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