WO2022107713A1

WO2022107713A1 - Motor and stator manufacturing method

Info

Publication number: WO2022107713A1
Application number: PCT/JP2021/041863
Authority: WO
Inventors: 浩威西野; 光生児玉
Original assignee: ミネベアミツミ株式会社
Priority date: 2020-11-19
Filing date: 2021-11-15
Publication date: 2022-05-27
Also published as: JPWO2022107713A1

Abstract

A motor (MT) comprises a rotor (70) which has magnets (71), and a stator (ST) which faces the rotor. The stator comprises an annular core back (50) and teeth (TT) each formed by laminating a plurality of plate materials (10, 20). The plate materials include first flat-plate members (10) and second flat-plate members (20). The teeth are each formed by the second flat-plate members (20). The first flat-plate members are disposed at ends of the teeth.

Description

Manufacturing method of motor and stator

The present invention relates to a method for manufacturing a motor and a stator.

In rotary electric machines such as motors and generators, a technique is known in which a stator core constituting a stator is formed from a core back and a plurality of teeth portions separated in the circumferential direction.

Japanese Unexamined Patent Publication No. 2004-173390 Japanese Unexamined Patent Publication No. 2004-242384 International Publication No. 2016/178368

However, when a plurality of tooth portions are arranged in the circumferential direction to form a stator, it is difficult to guarantee the roundness of the stator. Such deterioration of roundness may cause a decrease in the efficiency of the torque generated with respect to the current applied to the motor.

One aspect is to provide a method of manufacturing a motor and a stator that can improve efficiency.

In one embodiment, the motor comprises a rotor having a magnet and a stator facing the rotor. The stator includes an annular core back portion and a teeth portion formed by laminating a plurality of plate materials. The plurality of plate members include a first flat plate-shaped member and a second flat plate-shaped member. The teeth portion is composed of the second flat plate-shaped member. The first flat plate-shaped member is arranged at the end of the teeth portion.

According to one aspect, efficiency can be improved.

FIG. 1 is a plan view showing an example of the first stator sheet in the embodiment. FIG. 2 is a plan view showing an example of the second stator sheet in the embodiment. FIG. 3 is a plan view showing an example of the first stator sheet to which the second stator sheet is joined in the embodiment. FIG. 4 is a perspective view showing an example of the stack assembly in the embodiment. FIG. 5 is a cross-sectional view showing an example of the stack assembly in the embodiment. FIG. 6 is a perspective view showing an example of the assembly process of the stator coil assembly in the embodiment. FIG. 7 is a perspective view showing an example of a stator coil assembly to which an inner insulator is attached according to the embodiment. FIG. 8 is a perspective view showing an example of a stator coil assembly to which a coil is attached according to the embodiment. FIG. 9 is a perspective view showing an example of a stator coil assembly to which an outer insulator is attached according to the embodiment. FIG. 10 is a perspective view showing an example of the stator assembly process in the embodiment. FIG. 11 is a perspective view showing an example of the stator in the embodiment. FIG. 12 is a plan view showing an example of a punching process of the first stator sheet in the embodiment. FIG. 13 is a cross-sectional view showing an example of the motor in the embodiment. FIG. 14 is a cross-sectional view showing an example of the positional relationship between the stator sheet and the magnet in the embodiment. FIG. 15 is an enlarged cross-sectional view showing an example of the positional relationship between the stator sheet and the magnet in the embodiment. FIG. 16 is a perspective view showing an example of the first stator sheet in the modified example. FIG. 17 is an exploded perspective view showing an example of the stack assembly in the modified example. FIG. 18 is a perspective view showing an example of the stack assembly in the modified example. FIG. 19 is a perspective view showing an example of the stator coil assembly in the modified example. FIG. 20 is a perspective view showing an example of a stator coil assembly to which an outer peripheral ring is attached in a modified example.

Hereinafter, embodiments of the motor and stator manufacturing method disclosed in the present application will be described in detail with reference to the drawings. The relationship between the dimensions of each element in the drawing, the ratio of each element, etc. may differ from the reality. Even between the drawings, there may be parts where the relationship and ratio of the dimensions are different from each other. In each drawing, in order to make the explanation easy to understand, a coordinate system including at least one of the axial direction (rotational axis direction of the motor MT), the radial direction, and the circumferential direction in the motor MT described later may be illustrated. .. Further, in the following, the rotation axis direction of the motor MT may be simply referred to as "axial direction".

In the embodiment, the stack assembly SA constituting the stator ST is formed by laminating a plurality of second stator sheets 20 shown in FIG. 2 on the first stator sheet 10 shown in FIG. 1 in the axial direction. The first stator sheet 10 is an example of a first flat plate-shaped member, and the second stator sheet 20 is an example of a plurality of flat plate-shaped members and a second flat plate-shaped member. FIG. 1 is a plan view showing an example of the first stator sheet in the embodiment. FIG. 2 is a plan view showing an example of the second stator sheet in the embodiment.

The first stator sheet 10 in the embodiment is a flat plate-shaped member made of a non-magnetic material such as resin. In the embodiment, the thickness of the first stator sheet 10 is, for example, about 1.0 mm. As shown in FIG. 1, the first stator sheet 10 includes a substantially circular central portion 15 and a plurality of projecting portions 11 protruding in the radial direction from the outer periphery of the central portion 15. Although FIG. 1 describes the first stator sheet 10 having six protrusions 11, the number of protrusions 11 is not limited to this.

As shown in FIG. 1, a plurality of hole portions 16 and a plurality of notched portions 17 are formed between the central portion 15 and the protruding portion 11. The plurality of holes 16 and the plurality of notches 17 are formed, for example, at equal intervals in the circumferential direction.

Further, as shown in FIG. 1, the plurality of protruding portions 11 are formed at equal intervals in the circumferential direction. A plurality of

caulking portions

12 and 13 and an arc-shaped portion 14 formed so as to face the central portion 15 are formed in each protruding portion 11.

Next, the second stator sheet 20 in the embodiment is a flat plate-shaped member made of a magnetic material such as a magnetic steel plate. The second stator sheet 20 is formed of, for example, a magnetic material having a thickness of about 0.5 mm. That is, in the embodiment, the thickness of the first stator sheet 10 made of resin or the like is formed to be slightly larger than the thickness of the second stator sheet 20 in order to secure the rigidity. Further, the first stator sheet 10 may be formed by using a magnetic material like the second stator sheet 20, but a non-magnetic material such as a resin is used in consideration of suppressing iron loss, which will be described later. Is preferable.

As shown in FIG. 2, the second stator sheet 20 includes a protruding portion 21 and an arc-shaped portion 24. Further, the protruding portion 21 is formed with, for example, a plurality of caulking

portions

22 and 23 which are boss portions protruding in the axial direction. The plurality of

caulking portions

22, 23 are formed at positions facing each other in the axial direction with the

caulking portions

12, 13 of the first stator sheet 10, respectively. Further, a fitting portion 25 is further formed in the vicinity of the tip portion on the outer diameter side of the protruding portion 21 in the radial direction.

Next, a configuration in which the second stator sheet 20 is laminated on the first stator sheet 10 will be described with reference to FIG. FIG. 3 is a plan view showing an example of the first stator sheet to which the second stator sheet is joined in the embodiment. FIG. 3 shows a state in which one second stator sheet 20 is laminated on the first stator sheet 10 as viewed from above in the axial direction.

As shown in FIG. 3, each second stator sheet 20 is laminated on any one of the protruding portions 11 of the first stator sheet 10. At that time, the caulked portion 22 of the second stator sheet 20 is fixed to the caulked portion 12 of the first stator sheet 10 by caulking. Similarly, the caulked portion 23 of the second stator sheet 20 is fixed to the caulked portion 13 of the first stator sheet 10 by caulking. As a result, the second stator sheet 20 and the first stator sheet 10 are fixed so that the projecting portion 11 and the projecting portion 21, and the arc-shaped portion 14 and the arc-shaped portion 24 are overlapped with each other in the top view. Although the number and shape of the caulked portions are not limited to those shown in the figure, by providing a plurality of caulked portions, it is possible to suppress the positional deviation and rotation between the first stator sheet 10 and the second stator sheet 20.

In the embodiment, the second stator sheet 20 is similarly fixed to the other protruding portion 11 of the first stator sheet 10. Further, the second stator sheet 20 is further laminated and fixed to another second stator sheet 20 which is directly or indirectly fixed to the first stator sheet 10. By repeating the stacking of the second stator sheets 20 in this way, the stack assembly SA as shown in FIGS. 4 and 5 is formed.

FIG. 4 is a perspective view showing an example of the stack assembly in the embodiment. FIG. 5 is a cross-sectional view showing an example of the stack assembly in the embodiment. FIG. 5 shows a cross section cut along the line AA of FIG. As shown in FIGS. 4 and 5, the stack assembly SA in the embodiment is formed by laminating a plurality of second stator sheets 20 on the six protrusions 11 of the first stator sheet 10. The second stator sheet 20 laminated on the six protrusions 11 constitutes the teeth Ta to Tf, respectively. In the following, when the teeth Ta to Tf are expressed without distinction, they may be referred to as the teeth portion TT.

As shown in FIG. 5, in the stack assembly SA, the second stator sheet 20 constituting the teeth Ta is in contact with each of the laminated second stator sheets 20 constituting the other teeth Tb to Tf separated in the circumferential direction. Not. However, the teeth Ta is indirectly connected to other teeth Tb to Tf separated in the circumferential direction via the central portion 15 of the first stator sheet 10. As described above, the stack assembly SA is composed of the teeth Ta to Tf and the first stator sheet 10.

As shown in FIGS. 6 to 9, the inner insulator 31, the coil 40, and the outer insulator 32 are mounted on the stack assembly SA, so that the stack assembly SA forms the stator coil assembly CA. FIG. 6 is a perspective view showing an example of the assembly process of the stator coil assembly in the embodiment. FIG. 6 shows a configuration in which the inner insulator 31, the coil 40, and the outer insulator 32 are attached to the teeth Tb to Tf but not to the teeth Ta in the assembly process of the stator coil assembly CA.

Next, as shown in FIG. 7, the inner insulator 31 is attached to the stack assembly SA. FIG. 7 is a perspective view showing an example of a stator coil assembly to which an inner insulator is attached according to the embodiment. The inner insulator 31 constitutes the insulator 30 together with the outer insulator 32. The inner insulator 31 is attached to the stack assembly SA from the outside in the radial direction.

Next, as shown in FIG. 8, the coil 40 is mounted on the stack assembly SA via the inner insulator 31. FIG. 8 is a perspective view showing an example of a stator coil assembly to which a coil is attached according to the embodiment. In an embodiment, the coil 40 is composed of, for example, a flat wire and is prewound before being mounted on the stack assembly SA. Further, both ends of the flat wire wound around the coil 40 are drawn out as lead wires 41. The coil 40 is mounted on the stack assembly SA from the outside in the radial direction via the inner insulator 31.

Then, as shown in FIG. 9, the outer insulator 32 is attached to the stack assembly SA. FIG. 9 is a perspective view showing an example of a stator coil assembly to which an outer insulator is attached according to the embodiment. In the embodiment, the outer insulator 32 is attached to the stack assembly SA from the outside in the radial direction so as to be inserted between the stack assembly SA and the coil 40. In this way, the stator coil assembly CA is configured by mounting the insulator 30 and the coil 40 on each of the teeth Ta to Tf and the first stator sheet 10 constituting the stack assembly SA.

As described above, the teeth Ta to Tf and the first stator sheet 10 constituting the stack assembly SA in the embodiment do not have a portion protruding in the circumferential direction on the outer side in the radial direction. As a result, the inner insulator 31, the outer insulator 32, and the wound coil 40 can be mounted from the outside in the radial direction. However, the configuration for attaching the insulator and the coil is not limited to this, for example, the insulator is attached from the upper side and the lower side in the axial direction of the stack assembly SA, and the coil is wound around the stack assembly SA via the insulator. You may.

Then, as shown in FIGS. 10 and 11, the stator coil assembly CA constitutes the stator ST by being mounted on the stator ring 50 which is the core back portion. FIG. 10 is a perspective view showing an example of the stator assembly process in the embodiment. FIG. 11 is a perspective view showing an example of the stator in the embodiment. The stator ring 50 shown in FIG. 10 is formed by laminating a plurality of rings manufactured by pressing a steel plate such as an electromagnetic steel plate in the axial direction. As shown in FIG. 10, a plurality of fitting grooves 51 are formed on the inner peripheral side of the stator ring 50 in the radial direction at positions facing each of the teeth Ta to Tf.

As shown in FIGS. 10 and 11, the stator ring 50 is mounted on the stator coil assembly CA. At that time, the fitting portion 25 of each tooth Ta to Tf is fitted into the fitting groove 51 formed in the stator ring 50, respectively. Further, the stator coil assembly CA and the stator ring 50 are fixed so as not to have a gap by, for example, an adhesive, but the present invention is not limited to this, and the stator coil assembly CA and the stator ring 50 may be fixed by other methods such as welding.

As a result, the stator coil assembly CA is fixed to the stator ring 50 formed so as to guarantee the roundness while maintaining the roundness, so that the roundness of each teeth Ta to Tf can be maintained.

In the embodiment, even when the stator coil assembly CA is mounted on the stator ring 50, the teeth Ta to Tf are indirectly connected via the first stator sheet 10, so that the teeth Ta to Tf are connected to each other indirectly. The roundness of is secured by the first stator sheet 10 to which the second stator sheet 20 is fixed. Therefore, it is possible to reduce the value of roundness and improve the performance, it is possible to bring the value of the torque generated with respect to the current close to the ideal value, and improve the efficiency of the motor. Can be done.

Then, as shown in FIG. 12, each tooth Ta to Tf becomes a mutually independent member by separating the central portion 15 of the first stator sheet 10. FIG. 12 is a plan view showing an example of a punching process of the first stator sheet in the embodiment. As shown in FIG. 12, the central portion 15 of the first stator sheet 10 is punched out to form an opening 19 in the first stator sheet 10. At that time, the plurality of holes 16 and the plurality of notches 17 shown in FIG. 1 function as perforations when separating the central portion 15 and the protruding portion 11, so that the central portion 15 can be easily projected. It can be separated from the portion 11.

At this stage, each of the teeth Ta to Tf becomes an independent component from each other, but since each of the teeth Ta to Tf is fixed to the stator ring 50, deterioration of the roundness of the stack assembly SA is suppressed. To. Further, when the central portion 15 is punched out, the convex portion 18 may remain on each tooth Ta to Tf, that is, a part of the first stator sheet 10 may protrude inward in the radial direction from the second stator sheet 20. be. In other words, the area of the first stator sheet 10 is larger than the area of the second stator sheet 20. At this time, it is possible to secure a clearance when punching out the first stator sheet 10, which facilitates manufacturing.

Then, the stator ST is mounted on the frame 60, and the rotor 70 is inserted to form the motor MT. FIG. 13 is a cross-sectional view showing an example of the motor in the embodiment. As shown in FIG. 13, the rotor 70 is inserted into the opening 19 formed by punching out the central portion 15 of the first stator sheet 10. The rotor 70 is rotatably supported by, for example, the shaft 80. Further, a plurality of magnets 71 are arranged on the outer peripheral surface of the rotor 70. The magnet 71 is a permanent magnet such as neodymium sintered.

By the way, at the axial end of the magnet 71 arranged on the outer peripheral surface of the rotor 70, when a magnetic material that does not face the magnet is provided, iron loss tends to increase due to hysteresis loss. Therefore, in the embodiment, the stack assembly SA including the laminated teeth TT is formed so as to be longer than the magnet 71 in the axial direction as shown in FIGS. 14 and 15, but the magnet 71 shown in FIG. 15 is formed. The end portion 7a in the axial direction of the tooth TT is arranged so as to face the second stator sheet 20 made of a magnetic material, not the first stator sheet 10 arranged at the end portion in the axial direction of the teeth TT.

FIG. 14 is a cross-sectional view showing an example of the positional relationship between the stator sheet and the magnet in the embodiment. FIG. 15 is an enlarged cross-sectional view showing an example of the positional relationship between the stator sheet and the magnet in the embodiment. FIG. 15 is an enlarged view of the portion shown in the frame F of FIG. As shown in FIG. 15, the axial length L1 of the tooth portion TT is larger than the axial length L2 of the magnet 71. More specifically, in the embodiment, the end portion 7a of the magnet 71 in the axial direction faces the boundary portion B between the first stator sheet 10 and the second stator sheet 20 of the stack assembly SA. That is, the magnet 71 faces the second stator sheet 20 of the teeth portion TT in the radial direction, but does not face the first stator sheet 10.

In the examples shown in FIGS. 14 and 15, the magnetic flux directed in the radial direction (upper side in the drawing) from the end portion 7a of the magnet 71 flows to the second stator sheet 20 formed of the magnetic steel plate, so that the magnetic flux of the magnet 71 is maximized. It can be used to a limited extent, and the increase in iron loss can be suppressed by providing the first stator sheet 10 made of a non-magnetic material such as aluminum or resin at the end portion not facing the magnet.

As described above, the motor MT in the embodiment has a rotor 70 having a magnet 71 and a stator ST facing the rotor 70. The stator ST includes an annular core back portion 50 and a teeth portion TT formed by laminating a plurality of flat plate-shaped

members

10 and 20. The plurality of plate members include a first flat plate-shaped member 10 and a second flat plate-shaped member 20. The tooth portion TT is composed of a second flat plate-shaped member 20. Further, the first flat plate-shaped member 10 is arranged at the end of the teeth portion TT. Further, the first flat plate-shaped member 10 may be made of, for example, a non-magnetic material. This can improve efficiency.

Further, in the method of manufacturing the stator ST in the embodiment, the annular core back portion 50, the teeth portion TT which is formed by laminating a plurality of flat plate-shaped members and protrudes inward in the radial direction from the core back portion 50, and the teeth. A stator having a coil 40 arranged in the portion TT is manufactured by combining the core back portion 50 and the teeth portion TT. The plurality of flat plate-shaped members are composed of a first flat plate-shaped member 10 made of a non-magnetic material and a second flat plate-shaped member 20 made of a magnetic material. The stator ST is manufactured by removing the central portion 15 of the first flat plate-shaped member 10 after the teeth portion TT is combined with the core back portion 50. In such a manufacturing method, the teeth Ta to Tf before the central portion 15 of the first flat plate-shaped member 10 is removed are integrated by the end portion 10 of the stack assembly SA, and do not need to be aligned. Therefore, productivity is improved.

By the way, although the embodiment of the present invention has been described so far, the present invention may be implemented in various different forms other than the above-described embodiment. For example, the central portion 15 of the first stator sheet 10 shown in FIG. 1 is not limited to a disk shape, and may be an annular shape having a hole portion formed in the central portion.

Further, as shown in FIG. 16, the first stator sheet may be configured not to include the central portion 15. FIG. 16 is a perspective view showing an example of the first stator sheet in the modified example. Also in the modified example, the first stator sheet A0 is a flat plate-shaped member made of a non-magnetic material such as resin. As shown in FIG. 16, in the first stator sheet A0 in the modified example, a plurality of projecting portions A1 are formed so as to project outward in the radial direction from the annular portion AA. That is, in the modified example, the plurality of projecting portions A1 are connected by the annular portion AA so as to extend side by side in the circumferential direction.

As shown in FIG. 16, the second stator sheet B0 is laminated on the protruding portion A1 of the first stator sheet A0 in the modified example in the axial direction. The first stator sheet A0 and the second stator sheet B0 are fixed by overlapping the caulked portions, for example, as in the embodiment. At that time, the first stator sheet A0 and the second stator sheet B0 may be fixed by, for example, in-mold caulking. Further, the first stator sheet A0 and the second stator sheet B0 may be formed with the same caulking portions as the

caulking portions

12, 13, 22 and 23 in the embodiment.

Then, a plurality of second stator sheets B0 are laminated on each of all the protruding portions A1 of the first stator sheet A0, and the first stator sheet A0 is further laminated in the axial direction, so that FIGS. 17 and 18 show. The indicated stack assembly SZ is formed. In other words, the stack assembly SZ is composed of a pair of first stator sheets A0 and a second stator sheet B0. FIG. 17 is an exploded perspective view showing an example of the stack assembly in the modified example. FIG. 18 is a perspective view showing an example of the stack assembly in the modified example. In the modified example, as shown in FIGS. 17 and 18, the first stator sheets A0 are fixed to both sides of the plurality of second stator sheets B0 in the axial direction. In the stack assembly SZ in the modified example, the plurality of second stator sheets B0 stacked in the axial direction each form a teeth portion TZ.

As shown in FIG. 18, in the modified example, the stator coil assembly CZ shown in FIG. 19 is formed by arranging the coil C0 in the stack assembly SZ. Although the stack assembly SZ is coated with insulation, other insulating means such as mounting an insulator (not shown) between the stack assembly SZ and the coil C0 may be used. FIG. 19 is a perspective view showing an example of the stator coil assembly in the modified example. As shown in FIG. 19, the coil C0 is wound around each tooth portion TZ of the stack assembly SZ via a pair of first stator sheets A0. The coil C0 is wound by, for example, a winding machine. In addition to the winding by the winding machine, the air core coil formed in advance may be arranged so as to be mounted on the teeth portion TZ and the first stator sheet A0.

In the modified example, the outer peripheral ring is fixed to the outer peripheral portion of the stator coil assembly CZ as shown in FIGS. 19 and 20. FIG. 20 is a perspective view showing an example of a stator coil assembly to which an outer peripheral ring is attached in a modified example. The outer peripheral ring D0 is formed of an electromagnetic steel sheet or the like, similarly to the stator ring 50 in the embodiment. The outer peripheral ring D0 is connected to the stator coil assembly CZ by press fitting or caulking. The outer peripheral ring D0 is an example of a cylindrical member.

Also in such a modified example, as in the embodiment, the spacing in the circumferential direction of each tooth portion TZ becomes equal, and the roundness of the stator ST can be improved, so that the cogging component can be reduced. Further, as in the embodiment, since the teeth portion TZ is connected by using the non-magnetic first stator sheet A0, iron loss and an increase in cogging torque are suppressed. Further, since the punching process of the first stator sheet becomes unnecessary, the manufacturing process can be simplified. Further, in the modified example, when winding the coil around the teeth portion TZ, the coil is wound from the outside to the inside in the radial direction by using the winding machine used for the outer rotor type motor. Can be done. As a result, even when the number of teeth portions TZ increases and the distance between the inner diameters between the teeth portions TZ becomes small, winding to the teeth portions TZ becomes easy.

Further, the present invention is not limited to the above embodiments. The present invention also includes those configured by appropriately combining the above-mentioned constituent elements. Further, further effects and modifications can be easily derived by those skilled in the art. Therefore, the broader aspect of the present invention is not limited to the above-described embodiment, and various modifications can be made.

10, A0 1st stator sheet, 11, A1 protruding part, 12, 13 caulking part, 14 arc-shaped part, 15 central part, 16 hole part, 17 notch part, 19 opening part, AA annular part, 20, B0 second Stator sheet, 21 projecting part, 22, 23 caulking part, 24 arc-shaped part, 25 fitting part, 30 insulator, 31 inner insulator, 32 outer insulator, 40, C0 coil, 41 lead wire, 50 core back part (stator ring) , 51 Fitting groove, 60 frame, 70 rotor, 71 magnet, 80 shaft, D0 outer ring, SA, SZ stack assembly, CA, CZ stator coil assembly, ST stator, MT motor, TT, TZ teeth part

Claims

With a rotor with a magnet,
With a stator facing the rotor,
The stator is
The annular core back and
It is equipped with a teeth part made by laminating multiple plates.
The plurality of plate members include a first flat plate-shaped member and a second flat plate-shaped member.
The tooth portion is composed of the second flat plate-shaped member.
The first flat plate-shaped member is a motor arranged at the end of the teeth portion.
The motor according to claim 1, wherein the axial length of the teeth portion is longer than the axial length of the magnet.
The motor according to claim 1 or 2, wherein the magnet faces the second flat plate-shaped member in the radial direction.
The invention according to any one of claims 1 to 3, wherein at least a part of the first flat plate-shaped member has a convex portion that protrudes inward in the radial direction from the second flat plate-shaped member. motor.
The motor according to any one of claims 1 to 4, wherein the first flat plate-shaped member is made of a non-magnetic material.
It has a plurality of the teeth portions and has a plurality of the teeth portions.
The plurality of teeth portions are arranged adjacent to each other in the circumferential direction by being connected to the first flat plate-shaped member in the axial direction.
The motor according to any one of claims 1 to 5.
The motor according to claim 6, wherein the plurality of the teeth portions are connected to each other by a tubular member on the outer peripheral side.
The first flat plate-shaped member includes an annular portion and a plurality of protrusions extending radially outward from the annular portion, and is arranged at both ends of the second flat plate-shaped member in the axial direction. The motor according to claim 6 or 7.
The annular core back and
A teeth portion that is made by laminating a plurality of plate materials and protrudes inward in the radial direction from the core back portion.
The coil arranged in the teeth portion and
Have,
A method for manufacturing a stator manufactured by combining the core back portion and the teeth portion.
The plurality of plate members are composed of a first flat plate-shaped member and a second flat plate-shaped member.
A method for manufacturing a stator, which is manufactured by removing the central portion of the first flat plate-shaped member after the teeth portion is combined with the core back portion.
The method for manufacturing a stator according to claim 9, wherein the first flat plate-shaped member is made of a non-magnetic material, and the second flat plate-shaped member is made of a magnetic material.