WO2018042634A1

WO2018042634A1 - Rotor, dynamo-electric machine, and method for manufacturing rotor

Info

Publication number: WO2018042634A1
Application number: PCT/JP2016/075873
Authority: WO
Inventors: 陽介山田
Original assignee: 日本電産株式会社
Priority date: 2016-09-02
Filing date: 2016-09-02
Publication date: 2018-03-08
Also published as: CN109643920A; JPWO2018042634A1

Abstract

A rotor of a dynamo-electric machine, the rotor rotating about a center shaft, has: a rotor core having a plurality of magnetic steel plates laminated in the axial direction, and a through-hole that passes through in the axial direction; and a magnet inserted in the through-hole, the rotor core having a securing section on at least one side in the axial direction, in which one or more magnetic steel plates, including the endmost magnetic steel plate, are plastically deformed, and the magnet being secured by the securing section.

Description

Rotor, rotating electrical machine, and method of manufacturing rotor

The present invention relates to a rotor, a rotating electrical machine, and a method for manufacturing the rotor.

Conventionally, an IPM (Interior Permanent Magnet) motor having a structure in which a permanent magnet for a field is embedded in a rotor is known. In Japanese Patent Laying-Open No. 2015-163019, a second laminated core in which a magnet insertion hole is formed is laminated on the first laminated core, and after inserting a magnet into the magnet insertion hole, A rotor structure for an IPM motor having a rotor laminated core body in which a third laminated core is laminated as an end plate is disclosed. In the rotor structure, both ends of the magnet inserted into the magnet insertion hole are sandwiched between the first and third laminated cores.

JP-A-2015-204718 discloses an embedded magnet rotor having a cylindrical rotor core, a plurality of permanent magnets, and a plurality of wedge members. The rotor core has a plurality of magnet insertion holes arranged in a ring shape and a plurality of wedge insertion holes arranged in a ring shape inside and outside the row of the respective magnet insertion holes. The plurality of permanent magnets are inserted into the plurality of magnet insertion holes, respectively. The plurality of wedge members are respectively inserted into the plurality of wedge insertion holes. The permanent magnets are fixed inside the magnet insertion holes by narrowing the magnet insertion holes as the rotor core is deformed by inserting the wedge members into the wedge insertion holes.

Japanese Patent Laying-Open No. 2015-163019 JP2015-204718A

According to the configurations disclosed in Japanese Unexamined Patent Publication Nos. 2015-163019 and 2015-204718, a permanent magnet can be fixed in the insertion hole without using an adhesive. However, in the configuration disclosed in Japanese Patent Application Laid-Open No. 2015-163019, the first laminated core and the third laminated core have different shapes from the second laminated core. That is, it is necessary to prepare a plurality of types of laminated cores having different shapes.

Further, according to the configuration disclosed in Japanese Patent Application Laid-Open No. 2015-204718, a wedge member for fixing the permanent magnet is required. That is, it is necessary to add a member to fix the permanent magnet, and the number of parts increases.

Therefore, an object of the present invention is to provide a technique that makes it possible to manufacture a rotor in which a magnet is embedded inside at a low cost. Another object of the present invention is to provide a rotating electrical machine that has such a rotor and can be manufactured easily and at low cost.

An exemplary rotor of the present invention is a rotor of a rotating electrical machine that rotates about a central axis, a rotor core having a plurality of magnetic steel plates laminated in the axial direction and having a through-hole penetrating in the axial direction, and the penetration And a magnet inserted into the hole. The rotor core has, on at least one side in the axial direction, a fixing portion in which at least one magnetic steel plate including the outermost magnetic steel plate is plastically deformed. The magnet is fixed by the fixing portion.

The exemplary rotating electrical machine of the present invention has the exemplary rotor of the present invention described above.

An exemplary method for manufacturing a rotor of the present invention is a method for manufacturing a rotor of a rotating electrical machine that rotates about a central axis, the first step of laminating a plurality of magnetic steel plates having openings in the axial direction, and a plurality of methods A second step of inserting the magnet into a through-hole formed by overlapping a plurality of the openings along with the lamination of the magnetic steel sheets, and at least one including the outermost magnetic steel sheet on at least one side in the axial direction. And a third step of fixing the magnet by plastic deformation of the magnetic steel sheets.

According to the exemplary present invention, it is possible to provide a technique that makes it possible to easily and inexpensively manufacture a rotor in which a magnet is embedded. Further, according to the exemplary present invention, it is possible to provide a rotating electrical machine that can be manufactured easily and at low cost.

FIG. 1 is a schematic cross-sectional view of a rotating electrical machine according to an embodiment of the present invention. FIG. 2 is a schematic plan view of a magnetic steel plate included in the rotor according to the embodiment of the present invention. FIG. 3 is a schematic plan view of a rotor core included in the rotor according to the embodiment of the present invention. FIG. 4 is a schematic sectional view taken along the line XX in FIG. FIG. 5 is a schematic diagram for explaining the relationship between the magnet and the fixed portion in the rotor according to the embodiment of the present invention. FIG. 6 is a schematic diagram for explaining a first modification of the rotor according to the embodiment of the present invention. FIG. 7 is a schematic diagram for explaining a second modification of the rotor according to the embodiment of the invention. FIG. 8 is a schematic diagram for explaining a third modification of the rotor according to the embodiment of the present invention. FIG. 9 is a schematic diagram for explaining a fourth modification of the rotor according to the embodiment of the invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. In this specification, the extending direction of the central axis A of the rotating electrical machine shown in FIG. 1 is simply referred to as “axial direction”, and the radial direction and the circumferential direction around the central axis A of the rotating electrical machine are simply “radial direction”. And called “circumferential direction”. Similarly, with respect to the rotor, the directions that coincide with the axial direction, the radial direction, and the circumferential direction of the rotating electrical machine when incorporated in the rotating electrical machine are simply referred to as “axial direction”, “radial direction”, and “circumferential direction”. I will decide. In this specification, the axial direction when the rotating electrical machine is arranged in the direction shown in FIG. 1 is defined as the vertical direction. The vertical direction is simply a name used for explanation, and does not limit the actual positional relationship or direction.

<1. Schematic configuration of rotating electrical machine>
FIG. 1 is a schematic cross-sectional view of a rotating electrical machine 1 according to an embodiment of the present invention. FIG. 1 is a cross-sectional view taken along a cut surface including the central axis A of the rotating electrical machine 1. As shown in FIG. 1, the rotating electrical machine 1 includes a rotor 10, a stator 20, and a casing 30. The casing 30 includes a casing body 31 and a casing cover 32. The casing body 31 is a bottomed cylindrical member having an opening 31a on the upper side in the axial direction. The casing body 31 accommodates the rotor 10 and the stator 20. The casing cover 32 is a lid that closes the opening 31 a of the casing body 31.

The rotor 10 rotates about the central axis A. The rotor 10 has a shaft 11. The shaft 11 is disposed at the rotation center of the rotor 10. The shaft 11 is a columnar member extending in the axial direction. The shaft 11 is rotatably supported by an upper bearing 33a and a lower bearing 33b that are arranged with an interval in the axial direction. The upper bearing 33 a is held by the casing cover 32. The lower bearing 33 b is held at the bottom of the casing body 31. In the present embodiment, the two

bearings

33a and 33b are ball bearings, but the type of bearing is not limited to a ball bearing, and may be a sleeve bearing or the like. The upper end portion of the shaft 11 protrudes upward from the casing cover 32. The protruding portion of the shaft 11 is used as an output shaft.

The rotor 10 has a rotor core 12 and a magnet 13. The rotor core 12 has a cylindrical shape and is arranged on the outer side in the radial direction of the shaft 11. The rotor core 12 has a configuration in which a plurality of magnetic steel plates 120 are laminated in the axial direction. The magnetic steel plate 120 is made of, for example, a silicon steel plate. The rotor core 12 has a shaft hole 12a extending in the axial direction at the center. The shaft 11 is inserted into the shaft hole 12a. Apart from the shaft hole 12a, the rotor core 12 has a through hole 12b penetrating in the axial direction. The through hole 12 b is disposed in the vicinity of the outer edge of the rotor core 12. In the present embodiment, a plurality of through holes 12b are arranged in the circumferential direction.

The magnet 13 is inserted into the through hole 12b. The magnet 13 is fixed in the through hole 12b. A method for fixing the magnet 13 will be described later. The magnet 13 is a permanent magnet for a field, and may be, for example, a sintered magnet or a bonded magnet. In the present embodiment, as described above, a plurality of through holes 12 b are arranged in the circumferential direction, and the rotor 10 has a plurality of magnets 13. In the rotating electrical machine 1, a field magnet 13 is embedded in the rotor 10. The rotating electrical machine 1 of the present embodiment is an IPM type rotating electrical machine.

The stator 20 is an armature of the rotating electrical machine 1. The stator 20 is provided in a substantially annular shape, and is disposed on the radially outer side of the rotor 10. The stator 20 is fixed to the casing body 31. The stator 20 includes a stator core 21, a coil 22, and an insulator 23.

The stator core 21 is a laminated steel plate in which magnetic steel plates such as silicon steel plates are laminated in the axial direction. The stator core 21 includes an annular core back 211 and a plurality of teeth 212 protruding radially inward from the core back 211. The coil 22 is wound around each tooth 212 via the insulator 23. The insulator 23 is an insulating member that electrically insulates the stator core 21 and the coil 22 from each other. When a drive current is supplied to the coil 22, a radial magnetic flux is generated in the teeth 212, which is a magnetic core. Thereby, circumferential torque is generated in the rotor 10, and the rotor 10 rotates about the rotation axis A.

<2. Details of rotor>
FIG. 2 is a schematic plan view of the magnetic steel plate 120 included in the rotor 10 according to the embodiment of the present invention. As shown in FIG. 2, the magnetic steel plate 120 has a circular first opening 120a at the center and is annular. The first opening 120a penetrates the magnetic steel plate 120 in the axial direction. The magnetic steel plate 120 has a plurality of rectangular second openings 120b in the vicinity of the outer edge. The second opening 120b penetrates the magnetic steel plate 120 in the axial direction. The second opening 120b has a longitudinal direction in the circumferential direction. The plurality of second openings 120b are arranged at equal intervals in the circumferential direction. In the present embodiment, the number of the plurality of second openings 120b is eight.

In the present embodiment, the magnetic steel plate 120 has a plurality of third openings 120c arranged at equal intervals in the circumferential direction between the first opening 120a and the second opening 120b. The third opening 120c has a trapezoidal shape and penetrates the magnetic steel sheet 120 in the axial direction. The third opening 120c is provided for the purpose of reducing the weight of the rotor core 12, for example, but may not be provided depending on circumstances.

The shaft hole 12a is formed by the plurality of first openings 120a overlapping with the lamination of the plurality of magnetic steel plates 120. In addition, a plurality of second openings 120b overlap to form the through hole 12b. The through hole 12b has a longitudinal direction in the circumferential direction. The plurality of through holes 12b are arranged at equal intervals in the circumferential direction. In the present embodiment, the number of the plurality of through holes 12b is eight. Since the magnets 13 are inserted into the respective through holes 12b, the number of the magnets 12 is also eight. In addition, the number of the through-holes 12b and the magnets 12 of this embodiment is an illustration, and may be made into another number.

FIG. 3 is a schematic plan view of the rotor core 12 included in the rotor 10 according to the embodiment of the present invention. FIG. 3 shows a state in which the magnet 13 is inserted into the through hole 12b and fixed. FIG. 4 is a schematic sectional view taken along the line XX in FIG. The rotor core 12 has, on at least one side in the axial direction, a fixing portion 14 in which at least one magnetic steel plate 120 including the outermost magnetic steel plate 120 is plastically deformed. The magnet 13 is fixed by the fixing portion 14. In the present embodiment, there are a plurality of magnets 13, but a fixing portion 14 is provided for each of the plurality of magnets 13.

In the fixing portion 14, a part of the inner wall of the through hole 12 b protrudes toward the magnet 13 due to plastic deformation of the magnetic steel plate 120. For this reason, the width | variety of the through-hole 12b becomes narrow in the location in which the fixing | fixed part 14 is provided. Thereby, the movement of the magnet 13 is limited. The fixed portion 14 is preferably in contact with the magnet 13. According to this configuration, it is possible to omit adding a part for fixing the magnet 13 or applying an adhesive to fix the magnet 13. For this reason, the rotor 10 of this embodiment can be manufactured simply and at low cost. Further, according to this configuration, the rotating electrical machine 1 in which the magnet 13 embedded in the rotor 10 hardly moves and the magnetic characteristics are stable can be manufactured easily and at low cost.

In this embodiment, as shown in FIG. 4, the rotor core 12 has fixed portions 14 on the upper and lower sides in the axial direction. However, this is an exemplification, and the fixing portion 14 may be provided on only one of the upper side and the lower side in the axial direction. In the present embodiment, only one upper magnetic steel plate 120 is plastically deformed in the axially upper fixed portion 14, and only one lower magnetic steel plate 120 is in the axially lower fixed portion 14. It is plastically deformed. However, this is merely an example, and a plurality of magnetic steel plates 120 including the outermost magnetic steel plate 120 may be plastically deformed in the fixing portions 14 on the upper and lower sides in the axial direction. The number of the magnetic steel plates 120 that are plastically deformed may be different between the axially upper fixed portion 14 and the axially lower fixed portion 14.

In addition, when the number of the magnetic steel plates 120 constituting the fixed portion 14 increases, the magnetic characteristics of the rotor core 12 may be deteriorated. For this reason, it is preferable that the number of the magnetic steel plates 120 constituting the fixing portion 14 is one at the outermost end or two at the outermost end and one adjacent thereto.

In this embodiment, the magnet 13 is caulked and fixed by the fixing portion 14. The fixing portion 14 is caulked in the radial direction. Specifically, the fixing portion 14 is crushed by applying a radially inward force to the radially outer end face of the magnetic steel plate 120. The fixing portion 14 projects a part of the inner wall of the through hole 12b radially inward. In other words, the radial width of the through hole 12b is narrowed at the place where the fixing portion 14 is provided. The fixing portion 14 fixes the magnet 13 by pressing it from the radial direction. In the present embodiment, the magnet 13 is in close contact with the fixed portion 14, and the possibility that the magnet 13 moves in the axial direction can be reduced even when vibration or the like occurs.

In the present embodiment, as shown in FIG. 3, the fixing portion 14 is provided in the central portion in the longitudinal direction of the through hole 12 b in plan view. According to this, it can avoid that the fixing | fixed part 14 is provided in the position biased with respect to the magnet 13 inserted in the through-hole 12b. For this reason, the magnet 13 can be firmly fixed by the fixing portion 14.

Note that the configuration shown in FIG. 3 is merely an example, and the fixing portion 14 may be provided at a position shifted from the central portion in the longitudinal direction of the through hole 12b. Moreover, in this embodiment, although the one fixing | fixed part 14 is provided with respect to each magnet 13, this is an illustration. A plurality of fixing portions 14 may be provided for each magnet 13.

In the present embodiment, the fixing portion 14 is a portion where the distance between the through hole 12b and the outer edge 12c of the rotor core 12 radially outside the through hole 12b is the longest. In other words, the fixing portion 14 is formed by caulking a portion of the rotor core 12 where the thickness is thickest on the radially outer side from the through hole 12b. According to this configuration, since the distance from the portion to which force is applied for caulking and fixing to the magnet 13 can be increased, the possibility of damaging the magnet 13 during caulking and fixing can be reduced.

In the present embodiment, as shown in FIG. 4, the axial length of the magnet 13 is shorter than the axial length of the rotor core 12. For this reason, the magnet 13 inserted into the through hole 12 b can be retracted with respect to the upper end surface and the lower end surface in the axial direction of the rotor core 12. According to this configuration, the magnet 13 can be fixed by contacting only the axial end portion of the magnet 13 with the fixing portion 14. For this reason, the part with a strong magnetic force of the magnet 13 can be utilized appropriately, and the fall of the magnetic characteristic of the rotor 10 can be suppressed.

If the length of the magnet 13 in the axial direction is too short, the fixing effect of the magnet 13 accompanying the plastic deformation of the magnetic steel plate 120 may not be obtained. The axial length of the magnet 13 is preferably in a range where contact between the magnet 13 and the fixed portion 14 can be obtained.

FIG. 5 is a schematic diagram for explaining the relationship between the magnet 13 and the fixed portion 14 in the rotor 10 according to the embodiment of the present invention. As shown in FIG. 5, the magnet 13 has a chamfered portion 13a at an end portion in the axial direction. In the present embodiment, the magnet 13 has chamfered portions 13a at the upper and lower end portions in the axial direction.

The chamfered portion 13a is a portion where processing for removing a sharp portion of the magnet 13 has been performed. In the present embodiment, the chamfered portion 13a is rounded with a rounded corner. However, this is merely an example, and the chamfered portion 13a may be a C chamfer that forms a surface that forms an angle of 45 ° with respect to the end surface in the axial direction, instead of the R chamfer.

As shown in FIG. 5, in this embodiment, the fixing | fixed part 14 is contacting the chamfer 13a. The chamfered portion 13a has a width in the axial direction. For example, it is preferable that the fixing portion 14 is designed to come into contact with the axial center position of the chamfered portion 13a. By comprising in this way, the influence of the stacking tolerance of the magnetic steel plate 120 and the dimensional tolerance of the magnet 13 can be suppressed, and the fixed portion 14 can be brought into contact with the axial end of the magnet 13 with high probability. According to this structure, in the structure which fixes the magnet 13 with the fixing | fixed part 14 which deformed the magnetic steel plate 120 plastically, possibility that the magnetic characteristic of the rotor 10 will fall can be suppressed.

<3. Manufacturing method of rotor>
The method for manufacturing the rotor 10 includes a first step of laminating a plurality of magnetic steel plates 120 having the second openings 120b in the axial direction. The magnetic steel plate 120 having the second opening 120b is formed by punching, for example. In the present embodiment, the magnetic steel sheet 120 has the first opening 120a and the third opening 120c in addition to the second opening 120b as described above. The number of magnetic steel plates 120 to be stacked is not particularly limited, and is determined according to required magnetic characteristics and the like. In the present embodiment, the shapes of the magnetic steel plates 120 stacked in the axial direction are all the same. The direction of each magnetic steel plate 120 is aligned in the same direction, and a plurality of magnetic steel plates 120 are laminated. The laminated magnetic steel plates 120 are integrated by, for example, caulking and fixing.

The method for manufacturing the rotor 10 includes a second step of inserting the magnet 13 into the through hole 12b formed by overlapping a plurality of second openings 120b with the lamination of the plurality of magnetic steel plates 120. In the present embodiment, a plurality of through holes 12b are provided at equal intervals in the circumferential direction. A magnet 13 is inserted into each of the plurality of through holes 12b. In the present embodiment, the magnet 13 is not magnetized at this point. However, the magnet 13 magnetized at this time may be inserted into the through hole 12b. In the present embodiment, a jig for adjusting the height position is used so that the height position of the magnet 13 inserted into the through hole 12b is an appropriate height position.

The rotor manufacturing method includes a third step of fixing the magnet 13 by plastically deforming at least one magnetic steel plate 120 including the outermost magnetic steel plate 120 on at least one side in the axial direction. In the present embodiment, one magnetic steel sheet 120 positioned at the extreme end is plastically deformed on both the upper side and the lower side in the axial direction. Specifically, one magnetic steel plate 120 located at the upper end and one magnetic steel plate 120 located at the lower end are plastically deformed by applying a radially inward force to a predetermined portion of the radially outer end surface. Is done. The predetermined locations where the radially inward force is applied are a plurality of locations so that one fixed portion 14 is formed for each magnet 13 in each of the upper and lower axial directions. The plastically deformed magnetic steel plate 120 is pressed against the magnet 13 and the magnets 13 are fixed by caulking.

After each magnet 13 is fixed, each magnet 13 is magnetized. After the magnetization, in the plurality of magnets 13 arranged in the circumferential direction, the magnetic poles on the surface facing the stator core 21 are alternately opposite to each other. In addition, the manufacturing process of the rotor 10 also includes a process of fitting the shaft 11 into the shaft hole 12a formed by overlapping a plurality of first openings 120a with the lamination of the plurality of magnetic steel plates 120. The step of fitting the shaft 11 may be performed after the magnet 13 is magnetized, but is not limited to this timing. For example, it may be performed after integrating a plurality of laminated magnetic steel plates 120.

According to the method for manufacturing the rotor 10 of the present embodiment, a plurality of magnetic steel plates 120 having the same shape are stacked, and a part of the plurality of stacked magnetic steel plates 120 is plastically deformed to fix the magnet 13. That is, according to the method for manufacturing the rotor 10 of the present embodiment, it is possible to omit adding a part for fixing the magnet 13 or applying an adhesive. For this reason, according to the manufacturing method of the rotor 10 of this embodiment, the rotor 10 can be manufactured simply and at low cost.

<4. Modification>
The configuration of the embodiment described above is merely an example of the present invention. The configuration of the embodiment may be changed as appropriate without departing from the technical idea of the present invention. In addition, a plurality of modified examples described above and a plurality of modified examples described later can be implemented in appropriate combinations within a possible range.

FIG. 6 is a schematic diagram for explaining a first modification of the rotor 10 according to the embodiment of the present invention. In the embodiment described above, the fixing portion 14 is in contact with the chamfered portion 13a. This configuration is exemplary. For example, as shown in FIG. 6, the fixed portion 14 may be configured to contact the upper end surface 13 b of the magnet 13.

FIG. 7 is a schematic diagram for explaining a second modification of the rotor 10 according to the embodiment of the present invention. In the embodiment described above, the fixing portion 14 is caulked in the radial direction. This configuration is exemplary. For example, the fixed portion may be configured to be caulked in the axial direction as indicated by broken line arrows in FIG. However, the configuration in which the fixing portion 14 is caulked in the radial direction can more reliably fix the magnet 13 than the configuration in which the fixing portion 14 is caulked in the axial direction.

FIG. 8 is a schematic diagram for explaining a third modification of the rotor 10 according to the embodiment of the present invention. In the embodiment described above, the magnet 13 embedded in the rotor 10 is configured to have a longitudinal direction in the circumferential direction. This configuration is exemplary. The present invention can be applied to, for example, a configuration in which the magnet 13 embedded in the rotor 10 has a longitudinal direction in the radial direction as shown in FIG. In this case, the position where the fixing portion 14 for fixing the magnet 13 is provided may be changed as appropriate from the position of the embodiment described above.

FIG. 9 is a schematic diagram for explaining a fourth modification of the rotor 10 according to the embodiment of the present invention. In the embodiment described above, one magnetic pole is formed by one magnet 13. This configuration is exemplary. In the configuration shown in FIG. 9, one magnetic pole is formed by two magnets 13 arranged in a V shape. The present invention can also be applied to a rotor having a configuration in which one magnetic pole is formed by a plurality of magnets as shown in FIG. In this case, the position where the fixing portion 14 for fixing the magnet 13 is provided may be changed as appropriate from the position of the embodiment described above.

The present invention can be widely applied to motors used for home appliances, automobiles, ships, airplanes, trains, and the like. In addition, the present invention can be widely applied to generators used for automobiles, electrically assisted bicycles, wind power generation, and the like.

DESCRIPTION OF SYMBOLS 1 ... Rotary electric machine 10 ... Rotor 12 ... Rotor core 12b ... Through-hole 12c ... Outer edge 13 ... Magnet 13a ... Chamfering part 14 ... Fixed part 120 ... Magnetic steel plate 120b ... second opening A ... central axis

Claims

A rotor of a rotating electrical machine that rotates about a central axis,
A plurality of magnetic steel plates are laminated in the axial direction, and a rotor core having a through hole penetrating in the axial direction;
A magnet inserted into the through hole;
Have
The rotor core has, on at least one side in the axial direction, a fixing portion in which at least one of the magnetic steel plates including the outermost magnetic steel plate is plastically deformed,
The magnet is fixed by the fixing portion.
The rotor according to claim 1, wherein the magnet is caulked and fixed by the fixing portion.
The rotor according to claim 2, wherein the fixing portion is caulked in a radial direction.
The rotor according to any one of claims 1 to 3, wherein an axial length of the magnet is shorter than an axial length of the rotor core.
The magnet has a chamfered portion at an axial end,
The rotor according to claim 1, wherein the fixing portion is in contact with the chamfered portion.
The rotor according to any one of claims 1 to 5, wherein the fixing portion is provided at a central portion in a longitudinal direction of the through hole in a plan view from an axial direction.
The rotor core is cylindrical;
The through hole has a longitudinal direction in the circumferential direction,
The rotor according to any one of claims 1 to 6, wherein the fixing portion is a portion where a distance between the through hole and an outer edge of the rotor core radially outside the through hole is longest.
A rotating electrical machine having the rotor according to any one of claims 1 to 7.
A method of manufacturing a rotor of a rotating electrical machine that rotates about a central axis,
A first step of laminating a plurality of magnetic steel plates having openings in the axial direction;
A second step of inserting the magnet into a through hole formed by a plurality of the openings overlapping with the lamination of the plurality of magnetic steel plates;
A third step of plastically deforming at least one of the magnetic steel plates including the outermost magnetic steel plate and fixing the magnet on at least one side in the axial direction;
A method for manufacturing a rotor.