CN112789786A - Stator, motor, and method for manufacturing stator - Google Patents

Abstract

One embodiment of the stator of the present invention is a stator for an outer rotor motor. The stator includes a plurality of core members arranged in a circumferential direction with respect to the central axis, and a plurality of connecting members connecting two adjacent core members of the plurality of core members. The core member has a tooth portion around which the coil is wound, and a coupling portion located on the central axis side of the tooth portion. The connecting members connect the connecting portions to each other.

Description

Stator, motor, and method for manufacturing stator

Technical Field

The invention relates to a stator, a motor and a method for manufacturing the stator. The application is based on Japanese patent application No. 2018-185873 and Japanese patent application No. 2018-185860 which are proposed by 9, 28.2018. The present application claims the benefit of priority to that application. The entire contents of said application are incorporated by reference into the present application.

Background

In a stator core formed by laminating electromagnetic steel sheets processed by punching and pressing, a split core for splitting the stator core for each tooth is used for the purpose of improving the yield of the electromagnetic steel sheets at the time of pressing, and the like. In the inner rotor type motor, the split cores arranged in a ring shape are surrounded from the outside in the radial direction, whereby the split cores can be easily coupled to each other. However, in the outer rotor type motor, since the rotor is disposed radially outward of the stator core, it is difficult to connect the split cores radially outward. For example, patent document 1 discloses an outer rotor type stator core having a structure in which teeth are fitted into recesses provided in an annular core.

Documents of the prior art

Patent document

Patent document 1: japanese laid-open publication No. 2017-225311

Disclosure of Invention

Problems to be solved by the invention

In the conventional structure, since the stator core includes the annular core, there is a problem that it is difficult to improve the yield of the material when the annular core is manufactured by punching. That is, in the conventional structure, a large amount of waste material is generated when manufacturing the stator core.

In view of the above circumstances, an object of the present invention is to provide a stator having excellent material yield and a motor having the stator.

Means for solving the problems

One embodiment of the stator of the present invention is a stator for an outer rotor motor. The stator has: a plurality of core pieces (core pieces) arranged in a circumferential direction with respect to the central axis; and a plurality of connecting members that connect two adjacent core pieces of the plurality of core pieces.

The core member has a tooth portion around which a coil is wound, and a coupling portion located on the central axis side of the tooth portion. The connecting member connects the connecting portions to each other.

In addition, an embodiment of the motor of the present invention includes: the stator; and a rotor that surrounds the stator from a radially outer side and rotates around the central axis.

In addition, one embodiment of a method for manufacturing a stator according to the present invention is a method for manufacturing a stator for an outer rotor type motor, including: a first arrangement step of arranging a plurality of core members in a circumferential direction with respect to a central axis, the plurality of core members being arranged with an angle formed between two adjacent core members and the central axis being a first arrangement angle; a winding step of winding a coil around the core; and a second arrangement step of arranging a plurality of the core members by setting an angle formed by the center axis and the two adjacent core members to a second arrangement angle smaller than the first arrangement angle.

ADVANTAGEOUS EFFECTS OF INVENTION

According to an embodiment of the present invention, a stator and a motor having the same are provided with excellent material yield. In addition, according to an embodiment of the manufacturing method of the present invention, a manufacturing method of a stator capable of performing an efficient winding step is provided.

Drawings

Fig. 1 is a sectional view of a motor according to an embodiment.

Fig. 2 is a plan view of a stator core of an embodiment.

Fig. 3 is a perspective view of an embodiment of a core.

Fig. 4 is a partial enlarged view of a stator core of an embodiment.

Fig. 5 is an exploded view of an embodiment of a stator.

Fig. 6 is a schematic cross-sectional view of an embodiment of a stator.

Fig. 7 is a partial cross-sectional view of a stator showing a projection according to a modification.

Fig. 8 is an exploded perspective view showing a positional relationship between a core member, a part of which is annularly arranged, and a jig in the method of manufacturing a stator according to the embodiment.

Fig. 9 is an enlarged plan view of a part of a stator core according to a modification.

Fig. 10 is a perspective view of a core member according to a modification.

Detailed Description

Hereinafter, a stator and a motor according to embodiments of the present invention will be described with reference to the drawings. In the drawings below, in order to facilitate understanding of each structure, the scale, the number, and the like of each structure may be different from the actual structure.

The Z-axis is shown in each figure. The central axis J shown in the drawings is an imaginary line extending parallel to the Z-axis direction. In the following description, a direction parallel to the axial direction of the central axis J, i.e., the Z-axis direction, is simply referred to as an "axial direction", a radial direction about the central axis J is simply referred to as a "radial direction", and a circumferential direction about the central axis J is simply referred to as a "circumferential direction".

In this specification, the positive side in the Z-axis direction in the axial direction is sometimes referred to as "upper side", and the negative side in the Z-axis direction in the axial direction is sometimes referred to as "lower side". The vertical direction, the upper side, and the lower side are directions used for explanation only, and are not limited to an actual positional relationship or a posture of the motor when the motor is used.

In this specification, a side that advances counterclockwise when viewed from the upper side toward the lower side, i.e., a side that advances in the direction of arrow θ, is referred to as "one of the circumferential directions". The side that advances clockwise when viewed from the upper side toward the lower side in the circumferential direction, i.e., the side that advances in the direction opposite to the arrow θ, is referred to as the "other side in the circumferential direction".

< Motor >

Fig. 1 is a sectional view of a motor 1 according to the present embodiment.

The motor 1 of the present embodiment is an outer rotor type motor. The motor 1 of the present embodiment is used, for example, as an in-wheel motor (in-wheel motor) of an electric motorcycle. Further, in the case where the motor 1 is used as an in-wheel motor, the motor 1 is supported on the vehicle in a state where the central axis J is arranged along the horizontal direction.

The motor 1 includes: stator 2, rotor 7, shaft (draft) 9, bearing holder 60, first bearing 61, and second bearing 62. Although not shown in fig. 1, the motor 1 includes a bus bar connected to a coil wire extending from the stator 2, and a circuit board that controls rotation of the rotor 7.

The shaft 9 is a cylindrical shaft extending along the center axis J. The shaft 9 is fixed to the stator 2. In the case where the motor 1 is used as an in-wheel motor, the shaft 9 is mounted on the frame of the vehicle so as not to be relatively rotatable.

A bearing holder 60 is fixed to the shaft 9. The bearing holder 60 is located on the underside of the stator 2. The bearing holder 60 holds the second bearing 62 from the radially inner side. The bearing holder 60 is provided with a wire drawing hole 60a penetrating in the axial direction. The wiring extending from the stator 2 is drawn out to the outside of the motor 1 through the wiring drawing hole 60 a.

< rotor >

The rotor 7 rotates around the central axis J. The rotor 7 is rotated by a magnetic field generated by supplying a drive current from an external device to the stator 2. In the case where the motor 1 is used as an in-wheel motor, a rim (rim) is fixed to the rotor 7, for example. The rotor 7 surrounds the stator 2 from the radially outer side.

The rotor 7 has: a rotor holder 72, a rotor magnet 71, a first cover member 73, and a second cover member 74.

The rotor holder 72 is a cylindrical shape extending in the axial direction with the center axis J as the center. A first cover member 73 is fixed to an upper end of the rotor holder 72. Further, a second cover member 74 is fixed to a lower end portion of the rotor holder 72. The upper end of the rotor holder 72 corresponds to the end on one side of the rotor holder 72 in the axial direction. The lower end of the rotor holder 72 corresponds to the other end of the rotor holder 72 in the axial direction.

The rotor magnet 71 is a permanent magnet in which different magnetic poles are arranged in the circumferential direction. The rotor magnet 71 is held on the inner peripheral surface of the rotor holder 72. The rotor magnet 71 is fixed to the inner circumferential surface of the rotor holder 72 with an adhesive, for example.

The first cover member 73 has a circular disk shape when viewed from the axial direction. The first cover member 73 covers the upper side (one side in the axial direction) of the stator 2. The first cover member 73 is provided with a first center hole 73b located at the center in a plan view, and a first bearing holding portion 73a surrounding the first center hole 73 b. The shaft 9 passes through the first central hole 73 b. The first bearing holding portion 73a holds the first bearing 61 from the radial outside.

The second cover member 74 has a circular disk shape when viewed from the axial direction. The second cover member 74 covers the lower side (the other side in the axial direction) of the stator 2. The second cover member 74 faces the first cover member 73 in the axial direction. The stator 2 is disposed in a space surrounded by the rotor holder 72, the first cover member 73, and the second cover member 74.

The second cover member 74 is provided with a second center hole 74b located at the center in plan view, and a second bearing holding portion 74a surrounding the second center hole 74 b. The shaft 9 and the bearing holder 60 are disposed radially inward of the second center hole 74 b. The second bearing holding portion 74a holds the second bearing 62 from the radially outer side.

The first bearing 61 and the second bearing 62 are arranged in line in the axial direction. The first bearing 61 is located on the upper side of the stator 2 and the second bearing 62 is located on the lower side of the stator 2. The first bearing 61 is disposed radially between the rotor 7 and the shaft 9. The first bearing 61 rotatably supports the rotor 7 with respect to the shaft 9. The second bearing 62 is disposed radially between the rotor 7 and the bearing holder 60. The second bearing 62 rotatably supports the rotor 7 with respect to the bearing holder 60.

< stator >

The stator 2 of the present embodiment is a stator for an outer rotor motor. The stator 2 surrounds the shaft 9 from the radially outer side. The stator 2 is fixed to the outer peripheral surface of the shaft 9. The stator 2 includes: a stator core 20 having teeth 21, a plurality of insulators 41, a plurality of coils 40, and a stator holder 8. The plurality of coils 40 are wound around the teeth 21 of the stator core 20 via the insulators 41.

Fig. 2 is a plan view of the stator core 20.

The stator core 20 includes an annular core back portion 28 and a plurality of teeth portions 21 extending radially outward from the core back portion 28. The teeth 21 are arranged in the circumferential direction with the center axis J as the center, and extend in the radial direction. A coil 40 is wound around the tooth 21. In the present embodiment, 36 teeth portions 21 are provided in the stator core 20.

The stator core 20 is a so-called split core. The stator core 20 has a plurality of core pieces 20P and a plurality of connecting members 30. That is, the stator 2 has a plurality of core pieces 20P and a plurality of connecting members 30. The plurality of core members 20P and the plurality of connecting members 30 constitute the stator core 20. The connecting member 30 joins two core pieces 20P adjacent in the circumferential direction among the plurality of core pieces 20P.

In the present embodiment, the stator core 20 has the core pieces 20P and the connection members 30 in the same number as each other. Therefore, one connecting member 30 joins only two core pieces 20P adjacent to each other. However, the core member may be a structure in which three or more core members 20P are connected by one connecting member. In this case, the number of core members becomes larger than the number of connecting members.

The plurality of core members 20P are arranged annularly along the circumferential direction. That is, the plurality of core members 20P are arranged in the circumferential direction with respect to the central axis J. In the present embodiment, 36 core members 20P and 36 connecting members 30 are provided in the stator core 20.

According to the present embodiment, since the stator core 20 includes the plurality of core members 20P, the coil 40 can be wound in a state where the core members 20P are separated from each other or in a state where the core members 20P are separated from each other in the circumferential direction. Therefore, the tip of the nozzle of the winding machine is easily inserted between the core members 20P, and the coil 40 is easily wound densely with respect to the core members 20P. As a result, the space factor of the coil 40 in the slit can be increased.

Fig. 3 is a perspective view of the core member 20P.

The core member 20P includes electromagnetic steel sheets laminated in the axial direction. In the present embodiment, the outer shapes of the stacked electromagnetic steel sheets are all the same shape.

The core 20P has: the tooth portion 21, the connecting portion 22 located radially inside the tooth portion 21, and the umbrella portion 21a located radially outside the tooth portion 21. In the present embodiment, the core 20P has one tooth 21 and one coupling portion 22. However, a structure in which one core member has a plurality of coupling portions may be adopted.

The tooth 21 is elongated in the radial direction with a uniform width. In the stator core 20, a plurality of teeth 21 are arranged at equal intervals in the circumferential direction. The umbrella portion 21a is wider in the circumferential direction than the tooth portion 21. The radially outward surface of the umbrella portion 21a is arcuate with the center axis J as the center when viewed from the axial direction.

The coupling portion 22 is located radially inward of the tooth portion 21. That is, the coupling portion 22 is located on the central axis J side of the tooth portion 21. The coupling portion 22 has a large width in the circumferential direction with respect to the tooth portion 21. That is, the dimension of the coupling portion 22 in the direction orthogonal to the radial direction is larger than the dimension of the tooth portion 21 in the direction orthogonal to the radial direction. The coupling portion 22 has a through hole (hole portion) 29 penetrating in the axial direction. That is, the core member 20P has a through-hole 29. According to the present embodiment, since each of the plurality of core members 20P has the through-hole 29, the stator core 20 can be reduced in weight.

Fig. 4 is a partially enlarged view of the stator core 20.

The through-hole 29 is disposed sufficiently apart from the tooth portion 21 in the radial direction when viewed from the axial direction. Therefore, the cross-sectional area of the path of the magnetic flux passing from the tooth 21 to the connection 22 can be secured with a sufficient size. More specifically, the radial distance d between the through hole 29 and the tooth portion 21 is preferably equal to or more than half (d ≧ t/2) the dimension t of the tooth portion 21 orthogonal to the radial direction. The magnetic flux passing through the coupling portion 22 from the tooth portion 21 is branched into two paths at both circumferential sides of the coupling portion 22. That is, the magnetic flux directed to one side in the circumferential direction and the magnetic flux directed to the other side in the circumferential direction in the connection portion 22 are each half of the magnetic flux passing through the tooth portion 21.

By setting the distance d and the dimension t in the above-described relationship, the cross-sectional area of the path of the magnetic flux passing through the connection portion 22 can be made half or more of the cross-sectional area of the path of the magnetic flux passing through the tooth portion 21. Therefore, the magnetic flux density of the connection portion 22 is equal to or less than the magnetic flux density of the tooth portion 21. As a result, the magnetic resistance of the stator core 20 in the connecting portion 22 can be reduced, and power saving of the motor 1 can be achieved.

The coupling portion 22 has a pair of end surfaces 22a, 22b facing opposite sides in the circumferential direction. Here, one of the pair of end surfaces 22a and 22b facing one side in the circumferential direction is defined as a first end surface 22a, and the other facing the other side in the circumferential direction is defined as a second end surface 22 b. The first end surface 22a and the second end surface 22b extend in the radial direction when viewed from the axial direction. Of a pair of core members 20P adjoining in the circumferential direction, the second end face 22b of the core member 20P located on one side in the circumferential direction is in contact with the first end face 22a of the core member 20P located on the other side in the circumferential direction.

Here, a straight line passing through the center of the tooth portion 21 and extending in the radial direction is taken as a reference line L when viewed from the axial direction. The first end surface 22a gradually separates from the reference line L toward one side in the circumferential direction as viewed from the axial direction toward the radially outer side. That is, the first end surface 22a is inclined to one side in the circumferential direction with respect to the reference line L. The second end surface 22b gradually separates from the reference line L toward the other side in the circumferential direction as viewed from the axial direction, as it goes radially outward. That is, the second end surface 22b is inclined to the other side in the circumferential direction with respect to the reference line L. In the present embodiment, the inclination angle of the first end surface 22a with respect to the reference line L is equal to the inclination angle of the second end surface with respect to the reference line L. The angle formed by the first end surface 22a and the second end surface 22b is, for example, 10 degrees.

According to the present embodiment, the coupling portions 22 adjacent in the circumferential direction are in contact with each other, and the plurality of coupling portions 22 are annularly connected in the circumferential direction to constitute the core back portion 28. According to the present embodiment, the magnetic resistance of the stator core 20 can be reduced by having only one boundary surface of the members in the magnetic path between the core members 20P adjacent in the circumferential direction.

As a comparative example, a structure in which the coupling members of the core members adjacent in the circumferential direction are separated from each other and coupled by the coupling member including the magnetic body will be described. In the structure of the comparative example, the connecting member constitutes a part of the core back. Therefore, the number of the member boundary surfaces in the magnetic path between the core members adjacent in the circumferential direction is two or more, and the magnetic resistance of the stator core 20 is larger than that of the present embodiment.

The first end surface 22a is provided with a convex portion 23 protruding toward one side in the circumferential direction. In addition, a recess 24 recessed toward one side in the circumferential direction is provided on the second end surface 22 b. That is, the coupling portion 22 has a convex portion 23 protruding from the first end surface 22a and a concave portion 24 recessed in the second end surface 22 b. The outer shapes of the convex portions 23 and the concave portions 24 are arc-shaped as viewed from the axial direction.

In a pair of core members 20P adjacent in the circumferential direction, the convex portions 23 of the core member 20P located on the other side in the circumferential direction are fitted into the concave portions 24 of the core member 20P located on one side in the circumferential direction. That is, the coupling portions 22 adjacent in the circumferential direction are fixed by the connecting member 30 in a state where the convex portions 23 enter the concave portions 24.

According to the present embodiment, in the coupling portions 22 adjacent in the circumferential direction, the convex portions 23 are fitted into the concave portions 24, whereby the positional deviation in the radial direction of the coupling portions 22 adjacent in the circumferential direction from each other can be suppressed. In addition, the positioning of the core members 20P in the assembling step is facilitated.

According to the present embodiment, in the coupling portion 22 adjacent in the circumferential direction, a part of the outer peripheral surface of the convex portion 23 and a part of the inner peripheral surface of the concave portion 24 are in face-to-face contact in the radial direction. Therefore, even when a force in the radial direction is applied to the single core 20P, the convex portions 23 and the concave portions 24 interfere with each other, and the movement of the core 20P is restricted. As a result, the strength of connection between the core members 20P can be increased.

The connecting portion 22 has a first ridge 25 and a second ridge 26. The first ridge 25 and the second ridge 26 protrude radially inward. The first ridge 25 and the second ridge 26 extend in the same shape along the axial direction. The first ridges 25 and the second ridges 26 are arranged in the circumferential direction. The width dimension of the first raised strip 25 in the circumferential direction is equal to the width dimension of the second raised strip 26 in the circumferential direction. The first raised strip 25 is located at one end in the circumferential direction of the radially inner end surface of the coupling portion 22. The second raised strip 26 is located at the other end in the circumferential direction of the radially inner end surface of the coupling portion 22. In the coupling portions 22 adjacent to each other in the circumferential direction, the side surface of the second projected strip 26 of one coupling portion 22 and the side surface of the first projected strip 25 of the other coupling portion 22 contact each other in the circumferential direction.

The connection member 30 includes electromagnetic steel sheets stacked in the axial direction. The outer shapes of the electromagnetic steel sheets stacked in the axial direction are all the same. In the stator core 20, the connecting member 30 is located radially inward of the coupling portion 22. The connecting member 30 connects the coupling portions 22 of the core members 20P adjacent in the circumferential direction to each other.

The connecting member 30 has a body portion 31 and a pair of clamping portions 32. The body portion 31 is elongated in the circumferential direction. The pair of holding portions 32 extend radially outward from both circumferential ends of the main body 31.

The distance between the surfaces of the pair of sandwiching portions 32 facing each other is substantially equal to the sum of the width in the circumferential direction of the first ridge 25 and the width in the circumferential direction of the second ridge 26 of the core member 20P. In a pair of core members 20P adjacent in the circumferential direction, the second raised strip portions 26 of one of the core members 20P in the circumferential direction and the first raised strip portions 25 of the other of the core members 20P in the circumferential direction are sandwiched by a pair of sandwiching portions 32.

According to the present embodiment, the pair of holding portions 32 sandwich the first ridge 25 provided on one of the connection portions 22 adjacent to each other in the circumferential direction and the second ridge 26 provided on the other.

Thereby, the pair of core members 20P adjacent in the circumferential direction can be fixed and connected to each other.

According to the present embodiment, the plurality of core pieces 20P are linked by the plurality of connecting members 30. Therefore, the yield of the electromagnetic steel sheet is easily improved in the step of punching the connecting member 30, as compared with the case where the plurality of core members are connected by the annular connecting member. As a result, the stator 2 can be manufactured at low cost.

According to the present embodiment, the numbers of the core pieces 20P and the connecting members 30 are the same as each other. In addition, one connecting member 30 connects the coupling portions 22 of a pair of core members adjacent in the circumferential direction to each other. In the punching press, as the size of the molded product is reduced, the shape of the molded product is made closer to a rectangular shape, and the yield of the material is more likely to be improved. According to the present embodiment, the connecting member 30 can be reduced in size and can be made close to a rectangular shape, and therefore, the yield of the material (electromagnetic steel sheet) to be punched and stamped can be more easily improved.

In the present embodiment, a case where the pair of core pieces 20P are coupled to each other by one connecting member 30 is described. However, if the stator core 20 includes a plurality of connecting members 30, three or more core members may be connected by one connecting member.

According to the present embodiment, the connection member 30 includes electromagnetic steel sheets stacked in the axial direction. Therefore, in the stator core 20 of the present embodiment, the connecting member 30 can pass the magnetic flux through the inside as a part of the core back 28. That is, according to the present embodiment, the connecting member 30 is used as a part of the core back 28, whereby the radial dimension of the core back 28 can be increased, and the magnetic resistance of the stator core 20 can be reduced.

According to the present embodiment, the connection members 30 are stacked in the axial direction. The pair of clip portions 32 sandwich the first raised strip 25 and the second raised strip 26, and thus the pair of clip portions 32 receive a reaction force in the circumferential direction from the first raised strip 25 and the second raised strip 26. According to the present embodiment, the reaction force received by the connecting member 30 from the connecting portion 22 can be made to be the direction intersecting the stacking direction of the electromagnetic steel sheets, and separation of the stacked electromagnetic steel sheets can be suppressed.

In the present embodiment, the stator core 20 having the connection member 30 including the electromagnetic steel sheet is explained. However, according to the structure of the stator core 20 of the present embodiment, a resin material may be used as the material of the connecting member. In this case, the connecting member is formed by injection molding. Generally, injection molding is low in manufacturing cost, and the yield of the material is high as compared with punching. That is, by adopting the structure of the present embodiment, the connecting member 30 can be made of a resin material, the yield of the material can be easily improved, and an inexpensive stator core can be provided.

< stator fixer >

As shown in fig. 1, the stator holder 8 is disposed radially between the stator core 20 and the shaft 9. The stator holder 8 holds the stator core 20. The stator holder 8 is fixed to the outer peripheral surface of the shaft 9 via a bush 9 a.

Fig. 5 is an exploded view of the stator 2. Fig. 6 is a schematic sectional view mainly showing the stator 2 of the stator holder 8.

The stator holder 8 has a first holder member 81 and a second holder member 86 that face each other in the axial direction. In the present embodiment, the first retainer member 81 and the second retainer member 86 have the same shape.

The first holder member 81 has: a cylindrical portion 81a, a bottom plate portion 81b, a flange portion 81c, and a shaft support portion 81 d. Likewise, the second holder member 86 has: a cylinder portion 86a, a bottom plate portion 86b, a flange portion 86c, and a shaft support portion 86 d.

As shown in fig. 6, the cylindrical portions 81a and 86a of the first anchor member 81 and the second anchor member 86 are located radially inward of the stator core 20. That is, the cylindrical portion 81a and the cylindrical portion 86a are located radially inward of the plurality of core members 20P. The cylindrical portions 81a and 86a extend in the axial direction about the central axis J. The outer peripheral surfaces of the cylindrical portions 81a and 86a contact the connecting member 30 from the radially inner side. In the present embodiment, the tube portion 81a of the first anchor member 81 contacts the upper half region of the connecting member 30, and the tube portion 86a of the second anchor member 86 contacts the lower half region of the connecting member 30. The cylindrical portions 81a and 86a restrict the movement of the coupling member 30 inward in the radial direction, and suppress the coupling member 30 from coming off the coupling portion 22 of the core 20P. Thereby, the stator holder 8 suppresses the release of the connection between the plurality of core members 20P.

In the present embodiment, the first anchor member 81 and the second anchor member 86 have a cylindrical portion 81a and a cylindrical portion 86a, respectively, which are in contact with the connecting member 30. However, at least one of the first anchor member 81 and the second anchor member 86 may have a cylindrical portion that contacts the connecting member 30.

The flange portion 81c of the first anchor member 81 extends radially outward from the upper end of the cylindrical portion 81 a. The flange portion 86c of the second anchor member 86 extends radially outward from the lower end of the cylindrical portion 86 a. The flange portions 81c and 86c are annular with the central axis J as the center. The flange portion 81c of the first anchor member 81 and the flange portion 86c of the second anchor member 86 axially face each other.

The flange portion 81c of the first retainer member 81 is in contact with the upper end surface of the connecting member 30. Similarly, the flange portion 86c of the second anchor member 86 contacts the lower end surface of the connecting member 30. Thereby, the flange 81c and the flange 86c restrict the movement of the connecting member 30 in the axial direction, and prevent the connecting member 30 from coming off the coupling portion 22 of the core 20P.

The flange portion 81c of the first anchor member 81 is in contact with the upper end surfaces of the coupling portions 22 of the plurality of core members 20P. Similarly, the flange portion 86c of the second anchor member 86 contacts the lower end surfaces of the coupling portions 22 of the plurality of core members 20P. That is, the first anchor member 81 and the second anchor member 86 face each other in the axial direction, and sandwich the stator core 20 from both sides in the axial direction. Thereby, the first and second retainer members 81 and 86 suppress positional deviation of the plurality of core members 20P in the axial direction. The first retainer member 81 and the second retainer member 86 firmly hold the plurality of core members 20P and support the connection of the plurality of core members 20P.

The flange portion 81c of the first anchor member 81 is provided with a plurality of projecting portions 82 projecting downward. Similarly, the flange portion 86c of the second anchor member 86 is provided with a plurality of projecting portions 82 projecting upward. The protrusions 82 of the first and second retainer members 81 and 86 are inserted into the through-holes 29 of the core member 20P. In the present embodiment, 36 protrusions 82 are provided in the first anchor member 81 and the second anchor member 86, respectively, in the same number as the number of the through-holes 29. All the protrusions 82 are inserted into the through-holes 29, respectively.

According to the present embodiment, the rotation of the stator holder 8 around the central axis J is suppressed by inserting the protrusion 82 into the through-hole 29 of the stator core 20. That is, the protrusion 82 functions as a rotation stopper of the stator holder 8 with respect to the stator core 20.

In the present embodiment, the protrusions 82 are inserted into all the through-holes 29 of the stator core 20. However, if the stator holder 8 has at least one protrusion 82 inserted into the through-hole 29, the protrusion 82 functions as a rotation stopper of the stator holder 8.

In the present embodiment, the coupling portions 22 of all the core members 20P have through holes 29.

However, if at least one of the plurality of coupling portions 22 has a through-hole 29 and a protrusion 82 is inserted into the through-hole 29, the protrusion 82 functions as a rotation stopper of the stator holder 8.

According to the present embodiment, the protrusions 82 are inserted into the through holes 29 of all the core members 20P. The protrusion 82 restricts the movement of the core member 20P in the radial direction. Thereby, the stator holder 8 suppresses the release of the connection between the plurality of core members 20P.

In the present embodiment, the case where the protrusion 82 is provided on both the first retainer member 81 and the second retainer member 86 is exemplified. However, if the protrusion 82 is provided on at least one of the first retainer member 81 and the second retainer member 86, the release of the connection of the plurality of core members 20P can be suppressed.

Further, since both the first anchor member 81 and the second anchor member 86 have the same number of protrusions 82 as the number of through-holes 29, the stator anchor 8 can suppress the movement of the core 20P with good balance at both end portions in the axial direction. Therefore, according to the present embodiment, the effect of releasing the connection of the plurality of core members 20P can be improved.

The protrusion 82 of the present embodiment is formed by caulking the flange 81c and the flange 86 c. As shown in fig. 5, the flange portions 81c and 86c before the assembly step are flat plate-shaped. The protrusion 82 is formed by applying a force to the portions of the flange 81c and the flange 86c that overlap the through-hole 29 and plastically deforming the portions in a state where the flange 81c and the flange 86c are in contact with the upper surface or the lower surface of the stator core 20, respectively.

Fig. 7 is a partial sectional view of the stator 2 showing a projection 82A according to a modification that can be employed in the present embodiment. The projection 82A of the present modification is formed by deforming a part of the flange 81c, similarly to the projection 82. The projection 82A of the present modification is formed by applying a force to a portion of the flange 81c overlapping the through-hole 29, thereby breaking a portion of the flange and bending the flange downward.

Even in the case of using the projection 82A of the present modification, the same effect as the projection 82 can be obtained.

The structure of the protrusion is not limited to the above embodiment and the modifications. For example, another member may be fixed to the lower surface of the flange portion as the protrusion.

As shown in fig. 6, the bottom plate portion 81b of the first anchor member 81 and the bottom plate portion 86b of the second anchor member 86 extend along a plane orthogonal to the central axis J. The bottom plate 81b and the bottom plate 86b are located radially inward of the stator core 20. The bottom plate 81b and the bottom plate 86b are disk-shaped with the central axis J as the center. The radially outer ends of the bottom plate 81b and the bottom plate 86b are connected to the cylindrical portion 81a and the cylindrical portion 86 a. The radially inner ends of the bottom plate 81b and the bottom plate 86b are connected to the shaft support 81d and the shaft support 86 d. That is, the bottom plate portion 81b and the bottom plate portion 86b are positioned between the shaft support portion 81d and the shaft support portion 86d, and the cylindrical portion 81a and the cylindrical portion 86a, respectively, in the radial direction.

As shown in fig. 5, the bottom plate portion 81b of the first holder member 81 and the bottom plate portion 86b of the second holder member 86 are in contact with each other in the axial direction. The bottom plate portions 81b and 86b of the first and second anchor members 81 and 86 are fixed to each other.

According to the present embodiment, the stator core 20 can be sandwiched in the axial direction by the first anchor member 81 and the second anchor member 86. This ensures the fixing strength between the stator holder 8 and the stator core 20, and improves the joining strength between the core members 20P.

The first fixing hole (fixing hole) 83, the second fixing hole 84, and the fixing protrusion 85 are provided in the bottom plate portion 81b and the bottom plate portion 86b of the first anchor member 81 and the second anchor member 86, respectively. In the present embodiment, three first fixing holes 83, three second fixing holes 84, and three fixing protrusions 85 are provided in the bottom plate portion 81b and the bottom plate portion 86 b.

The first fixing hole 83 and the second fixing hole 84 penetrate in the axial direction. The first fixing hole 83 and the second fixing hole 84 are circular when viewed from the axial direction. The diameter of the first fixing hole 83 is slightly larger than that of the second fixing hole 84. In the bottom plate portion 81b and the bottom plate portion 86b, the first fixing holes 83 and the second fixing holes 84 are alternately arranged in the circumferential direction. The first fixing hole 83 of the first anchor member 81 and the second fixing hole 84 of the second anchor member 86 overlap each other as viewed from the axial direction. Similarly, the first fixing hole 83 of the second anchor member 86 and the second fixing hole 84 of the first anchor member 81 overlap each other when viewed from the axial direction.

The fixing protrusion 85 protrudes in a cylindrical shape from the outer edge of the second fixing hole 84 in the axial direction. The fixing projection 85 of the first holder member 81 projects toward the lower side (i.e., the second holder member 86 side). On the other hand, the fixing projection 85 of the second holder member 86 projects toward the upper side (i.e., the first holder member 81 side).

As shown in fig. 6, the fixing projection 85 of the second holder member 86 is inserted into the first fixing hole 83 of the first holder member 81. The front end of the fixing projection 85 of the second holder member 86 is located above the bottom plate portion 81b of the first holder member 81. A caulking portion 85a extending outward from the center of the second fixing hole 84 is provided at the tip of the fixing protrusion 85 of the second anchor member 86. The caulking portion 85a is formed by caulking for plastically deforming the tip of the fixing protrusion 85. The caulking portion 85a sandwiches the bottom plate portion 81b of the first anchor member 81 in the axial direction with the bottom plate portion 86b of the second anchor member 86. Thereby, the first holder member 81 and the second holder member 86 are fastened to each other. According to the present embodiment, the first anchor member 81 and the second anchor member 86 can be fixed to each other by performing caulking. In addition, according to the present embodiment, since no other parts are used for fixing the first holder member 81 and the second holder member 86, the motor 1 can be manufactured at low cost.

Here, the relationship between the first fixing hole 83 of the first anchor member 81, the second fixing hole 84 of the second anchor member 86, and the fixing protrusion 85 is described with reference to fig. 6. However, the same structure is also applied to the relationship between the first fixing hole 83 of the second anchor member 86, and the second fixing hole 84 and the fixing projection 85 of the first anchor member 81. In the present embodiment, each of the first retainer member 81 and the second retainer member 86 has three fixing projections 85. Therefore, the first holder member 81 and the second holder member 86 are fixed to each other at six points in total in the circumferential direction.

The shaft support portion 81d of the first holder member 81 has a cylindrical portion 81da and a conical portion 81 db. The cylindrical portion 81da is cylindrical with the center axis J as the center. The cylindrical portion 81da contacts the outer peripheral surface of the bush 9a fixed to the shaft 9. The conical portion 81db extends radially outward from the upper end of the cylindrical portion 81 da. The conical portion 81db is conical with the center axis J as the center. The conical portion 81db extends downward as it goes radially outward. The radially outer end of the conical portion 81db is connected to the bottom plate portion 81 b.

The shaft support portion 86d of the second holder member 86 has a cylindrical portion 86da and a conical portion 86 db. The shaft support portion 86d of the second anchor member 86 has a shape in which the shaft support portion 81d of the first anchor member 81 is inverted in the vertical direction, and has the same configuration.

According to the present embodiment, the stator holder 8 is fitted and fixed to the outer peripheral surface of the bush 9a at the cylindrical portions 81da and 86 da. Therefore, the fitting length can be sufficiently ensured along the axial direction. As a result, the stator holder 8 can be firmly fixed to the bush 9 a.

< manufacturing method >

Next, a method for manufacturing the stator 2 of the present embodiment will be described. That is, the stator 2 of the present embodiment is manufactured by the manufacturing method described below.

The method for manufacturing the stator 2 of the present embodiment mainly includes: a core member preparing step, a first arranging step, a winding step, a second arranging step, a third arranging step, a connecting step, and a fastener fixing step. The processing steps of the manufacturing method of the stator 2 are performed in the order described.

(core preparation step)

The core preparation step is a step of preparing a plurality of cores 20P and attaching the insulator 41 to each tooth portion 21. The core 20P is manufactured as follows: a plurality of electromagnetic steel sheets formed by punching and pressing are stacked in the axial direction and are connected to each other by caulking or the like. Further, in the present embodiment, 36 core members 20P are prepared per stator 2.

(first configuration step)

The first arranging step is a preliminary step for winding the coil 40 around the core member 20P. The first arranging step is a step of arranging a plurality of core members 20P in order to facilitate winding. The first disposing step is a step of disposing the plurality of core members 20P in the circumferential direction with respect to the central axis J.

Prior to the first configuring step, the plurality of core pieces 20P are first sorted into two or more groups. In the present embodiment, prior to the first arranging step, the 36 core pieces 20P are sorted into two groups of 18 each. The first arranging step is performed for each group of the core pieces 20P classified into two or more.

In the present specification, the group refers to a single or a collection of plural core members 20P. That is, the cores 20P belonging to one group may be singular.

In addition, if the core pieces 20P of all the groups are sorted in the singular number, the first arrangement step cannot be performed, and thus the core pieces 20P of all the groups are not sorted in the singular number.

As shown in fig. 8, in the first arranging step, the cores 20P of each group are arranged in a circular ring shape. At this time, the teeth 21 are arranged in the radial direction with the coupling 22 being radially inward in the core 20P. Therefore, in the first arranging step, the core members 20P are arranged radially with the central axis J as the center.

By the first arranging step, the plurality of core pieces 20P are arranged radially from each other at the first arranging angle Φ 1. That is, in the first arrangement step, the plurality of core members 20P are arranged with the angle formed by the adjacent two core members 20P and the central axis J set as the first arrangement angle Φ 1. The first configuration step is performed for each of the core pieces 20P classified into two or more groups. Therefore, the core pieces 20P arranged in the first arranging step are fewer than the total number of the core pieces 20P for the stator 2. Therefore, the first arrangement angle Φ 1 is larger than an angle (the second arrangement angle Φ 2 shown in fig. 2) formed by the core pieces 20P in the final stator core 20 with each other. In the present embodiment, since the cores 20P are divided into halves to form the respective groups and the cores 20P of the respective groups are arranged in the annular shape, the first arrangement angle Φ 1 is twice the second arrangement angle Φ 2.

The fixture 90 shown in fig. 8 is used in a first configuration step. That is, the first arranging step is a step of using the jig 90.

The jig 90 includes a disk-shaped base 92 and a plurality of holding projections 91 projecting from the base 92. The holding projection 91 projects upward from the upper surface of the jig 90. The holding projection 91 is elongated in the axial direction. The plurality of holding projections 91 are arranged in the circumferential direction with the center axis J as the center. In the present embodiment, each of the plurality of holding projections 91 has a pair of pins 91 a. The pair of pins 91a are cylindrical extending parallel to each other in the axial direction. The pair of pins 91a are arranged in the circumferential direction.

In the first arranging step, the holding projections 91 of the jig 90 are inserted into the through-holes 29 of the core members 20P of the respective groups. That is, the first arranging step is a step of inserting the holding projections 91 into the through-holes 29 of the plurality of core members 20P in each group. The plurality of core members 20P into which the holding projections 91 are inserted are aligned uniformly in the circumferential direction at the first arrangement angle Φ 1 without being angularly adjusted. That is, according to the present embodiment, the first arrangement step can be easily performed.

The through-hole 29 of the core member 20P is an elongated hole extending in a direction orthogonal to the radial direction when viewed from the axial direction. The through hole 29 has a size in the radial direction equal to or slightly larger than the diameter of the pin 91 a. In addition, in a state where the holding projection 91 is inserted into the through-hole 29, the pair of pins 91a are aligned in the longitudinal direction of the through-hole. Therefore, in the state where the holding projection 91 is inserted into the through-hole 29, the rotation of the core 20P around the holding projection 91 is suppressed. Thereby, the angle of the core 20P with respect to the jig 90 can be uniquely determined.

In the present embodiment, the holding projection 91 is inserted into the through hole 29 of the core member 20P. However, the hole into which the holding projection 91 is inserted need not necessarily penetrate the core 20P. That is, the core member 20P may be supported by a jig by inserting the holding projection 91 into the hole portion as long as the hole portion is elongated in the axial direction and opened in the axial direction.

(winding step)

The winding step is a step of winding the coil 40 around the tooth portion 21 of the core 20P via the insulator 41. The winding step is performed on each of the groups of the core members 20P having completed the first arranging step. That is, the winding step is performed for each group of the core members 20P. The winding step is performed in a state where the jig 90 shown in fig. 8 holds the core member 20P.

According to the present embodiment, the plurality of core members 20P subjected to the winding step are arranged at the first arrangement angle Φ 1 along the circumferential direction. The first disposition angle φ 1 is an angle larger than the second disposition angle φ 2. Therefore, the gap between the core pieces 20P subjected to the winding step becomes larger than that of the final stator core 20. According to the present embodiment, the tip of the nozzle of the winder that performs the winding step can be easily inserted between the core members 20P. Therefore, compared to the case where the winding step is performed in a state where the plurality of core members 20P are aligned at the second arrangement angle Φ 2, the winding step becomes easy, and the space factor of the coil is easily increased. The effect becomes more remarkable in the stator 2 having a large number of slits.

According to the present embodiment, the coil 40 may be continuously wound around the plurality of core members 120P in the circumferential direction. Therefore, compared to the case where the coils are wound individually on each of the plurality of core pieces 120P, the winding efficiency can be improved. Since the plurality of core pieces 120P are arranged in a row along the circumferential direction, the cross-wires connecting the coils 40 to each other can be provided in the winding step.

In addition, in the case of adopting the method for manufacturing the stator 2 of the present embodiment, since the winding step can be performed using the existing winding machine, a new equipment investment is not required.

In addition, the winding order of the plurality of coils 40 in the winding step is not particularly limited. In addition, a procedure of providing the extraction wire for connection with the bus bar is also not particularly limited.

For example, all the coils 40 in the group may be wound in series in the circumferential direction, and then a part of the crossing wires may be cut to form extraction wires.

(second configuration step)

The second arranging step is a step of arranging the plurality of core pieces 20P in the group at a second arranging angle Φ 2 (refer to fig. 2) along the circumferential direction. The second arranging step is performed on the group of the core members 20P having finished the winding step. In the second arranging step, an angle formed by the two core pieces 20P adjacent to each other with the central axis J is set as a second arranging angle Φ 2. Further, as described above, the second arrangement angle Φ 2 is an angle smaller than the first arrangement angle Φ 1. The second configuration step is performed after removing each group of the plurality of core pieces 20P from the jig 90.

(third configuration step)

The third configuration step is performed after the second configuration step. The third arranging step is a step of arranging the plurality of groups subjected to the second arranging step in a ring shape along the circumferential direction. By performing the third arranging step, all the core pieces 20P of the stator core 20 can be arranged in a ring shape to form the shape of the stator core 20.

(joining step)

The joining step is a step of joining the core members adjacent in the circumferential direction to each other at a second arrangement angle Φ 2. As shown in fig. 2, in the coupling step, the coupling members 30 are attached to the coupling portions 22 of the core members 20P adjacent in the circumferential direction to couple them to each other. The joining step is a step of forming the stator core 20. That is, the stator core 20 having the core members 20P arranged in the circumferential direction at the second arrangement angle Φ 2 is formed by passing through the joining step.

In the present embodiment, the joining step is performed after the third step. Therefore, in the present embodiment, the coupling step is performed for the plurality of core members 20P arranged annularly along the circumferential direction. According to the coupling step of the present embodiment, all the core members 20P can be coupled at the same time by using a jig or the like, and the workability of the coupling step is easily improved.

(modification of connection step)

After the linking step is performed for each of the classified groups, the linking step may be performed again to link the groups to each other. In this case, the linking step includes a first linking step performed for each group and a second linking step for linking the groups to each other. The first joining step is performed after the second arranging step to join the core members 20P adjacent in the circumferential direction in the group to each other. The second joining step is performed after the third arranging step, and joins the core members 20P located at the circumferential end portions of the adjacent groups to each other.

According to the coupling step of the present modification, after the core members 20P are coupled for each group in the first coupling step, the groups are coupled to each other in the second coupling step. Therefore, when the coupling step of the present modification is adopted, the method of manufacturing the stator 2 is performed in the order of the first coupling step, the third arranging step, and the second coupling step. According to the present modification, since the core members 20P in the group are connected to each other before the third arranging step is performed, handling of each group becomes easy, and workability in the third arranging step improves.

(step of fixing holder)

The stator holder fixing step is a step of mounting the stator holder 8 to the stator core 20. The fastener fixing step is performed after the connecting step is completed. The stator core 20 subjected to the stator fixing step has a plurality of core pieces 20P arranged in the circumferential direction at a second arrangement angle Φ 2.

As shown in fig. 6, the stator holder 8 has a first holder member 81 and a second holder member 86. The anchor fixing step of the present embodiment includes a fastening step and a protrusion forming step performed after the fastening step.

The fastening step is a step of fastening the first holder member 81 and the second holder member 86 to each other in the axial direction. The fastening step of the present embodiment is a step of fixing the first anchor member 81 and the second anchor member 86 to each other by caulking.

In the fastening step, first, the cylindrical portion 81a of the first anchor member 81 is inserted from above into the radial direction inside of the stator core 20, and the cylindrical portion 86a of the second anchor member 86 is inserted from below into the radial direction inside of the stator core 20. Further, the flange portion 81c of the first stator member 81 is brought into contact with the upper surface of the stator core 20, and the flange portion 86c of the second stator member 86 is brought into contact with the lower surface of the stator core 20. Simultaneously with these steps, the fixing projection 85 of the second holder member 86 is inserted into the first fixing hole 83 of the first holder member 81. Although not shown, the fixing projections 85 of the first holder member 81 are inserted into the first fixing holes 83 of the second holder member 86 at the same time.

In the fastening step, the front end of the fixing projection 85 is then swaged to the outside with respect to the center of the second fixing hole 84 to form a swaged portion 85 a. Thereby, the first holder member 81 and the second holder member 86 are fastened to each other.

The protrusion forming step is a step of plastically deforming a part of the first anchor member 81 and the second anchor member 86 (the flange portion 81c and the flange portion 86c in the present embodiment) to form the protrusion 82. In addition, the protrusion forming step is a step of forming the protrusion 82 and inserting the protrusion 82 into the through-hole 29 of the stator core 20. The formation of the protrusion 82 and the insertion of the protrusion 82 into the through-hole 29 can be performed simultaneously.

In the protrusion forming step, first, a force is applied to the portions of the flange portions 81c and 86c that overlap the through-holes 29. Thereby, the flange 81c and the flange 86c are plastically deformed to form the protrusion 82 inserted into the through hole 29.

In the protrusion forming step of the present embodiment, the protrusion 82 is formed on both the first retainer member 81 and the second retainer member 86. However, the protrusion forming step may be a step of forming the protrusion 82 on at least one of the first anchor member 81 and the second anchor member 86.

< modification of stator core >

A stator core 120 according to a modification example that can be used in the above embodiment will be described.

The same reference numerals are given to constituent elements of the same form as those of the above-described embodiment, and the description thereof will be omitted.

Fig. 9 is an enlarged plan view of a part of stator core 120 according to the present modification.

As in the above-described embodiment, the stator core 120 includes an annular core back portion 128 and a plurality of tooth portions 121 extending radially outward from the core back portion 128. The teeth 121 are arranged in the circumferential direction with the center axis J as the center, and extend in the radial direction.

Stator core 120 includes a plurality of core pieces 120P and a plurality of connecting members 130 that connect core pieces 120P to each other. The plurality of core members 120P are arranged annularly along the circumferential direction.

Fig. 10 is a perspective view of core 120P.

Core piece 120P has: the tooth 121, the connecting portion 122 located closer to the central axis J than the tooth 121, and the umbrella portion 121a located radially outward of the tooth 121. The tooth 121 and the umbrella 121a of this modification have the same configuration as that of the above-described embodiment.

As in the above-described embodiment, the coupling portion 122 is located at the radially inner end of the tooth portion 121. The coupling portion 122 is provided with a through hole 129 penetrating in the axial direction. The coupling portions 122 adjacent in the circumferential direction are in contact with each other and annularly connected to constitute the core back portion 128. The coupling portion 122 has a projection 123 on one circumferential end surface and a recess on the other circumferential end surface. In a pair of the core members 120P adjoining in the circumferential direction, the convex portions 123 are fitted into the concave portions 124.

The coupling portion 122 of the present modification includes a first arm portion 122A and a second arm portion 122B that extend radially inward. The first arm portion 122A and the second arm portion 122B are located at radially inward end portions of the coupling portion 122. The first arm portion 122A and the second arm portion 122B are arranged along the axial direction. The first arm portion 122A and the second arm portion 122B have the same cross-sectional shape along the axial direction.

The first arm portion 122A and the second arm portion 122B are line-symmetrical with respect to the reference line L when viewed from the axial direction. The first arm portion 122A extends radially inward. The first arm portion 122A extends toward one side in the circumferential direction as it goes toward the radially inner side. The second arm portion 122B extends radially inward. The second arm portion 122B extends toward the other circumferential side as it goes radially inward. That is, the direction in which the first arm portion 122A extends radially inward is circumferentially offset from the direction in which the second arm portion 122B extends radially inward. The first arm portion 122A and the second arm portion 122B extend in directions different from each other in the circumferential direction as they face radially inward.

Two first arm portions 122A and two second arm portions 122B are provided in core 120P. The first arm portions 122A and the second arm portions 122B are alternately arranged in the axial direction. The axial dimensions of the two first arm portions 122A and the two second arm portions 122B are all equal.

Core member 120P includes electromagnetic steel plates laminated in the axial direction. The magnetic steel sheet of the region having the first arm portion 122A and the magnetic steel sheet of the region having the second arm portion 122B are different in shape from each other in the axial direction. That is, the core 120P of the present modification is formed by stacking a plurality of electromagnetic steel plates having different shapes in the axial direction.

In the core pieces 120P adjacent to each other of the stator cores 120, the first arm portion 122A and the second arm portion 122B overlap in the axial direction. That is, in a pair of core pieces 120P adjacent in the circumferential direction, the first arm portion 122A of one core piece 120P and the second arm portion 122B of the other core piece 120P overlap each other as viewed from the axial direction. Surfaces of the first arm portion 122A and the second arm portion 122B facing each other in the axial direction contact each other. According to the present modification, it is possible to suppress the core members 120P adjacent in the circumferential direction from being positionally displaced relative to each other in the axial direction. As a result, the stability of the connection between the core members 120P is improved. Further, the cores 120P can be easily aligned in the axial direction in the assembling step.

The number of the first arm portions 122A and the second arm portions 122B provided in the connecting portion 122 is not limited, but at least one of them is preferably two or more. A case where two or more first arm portions 122A are provided in one core 120P will be described as an example. In this case, in the adjoining core pieces 120P, the second arm portion 122B is sandwiched between the two first arm portions 122A in the axial direction. Therefore, the movement of the core members 120P relative to each other toward both sides in the axial direction is restricted.

As shown in fig. 10, the first arm portion 122A has a pair of end surfaces 122Aa and 122Ab facing opposite sides in the circumferential direction. That is, the connecting portion 122 has a first end surface 122Aa and a second end surface 122 Ab. Here, one of the pair of end surfaces 122Aa and 122Ab facing one side in the circumferential direction is defined as a first end surface 122Aa, and the other facing the other side in the circumferential direction is defined as a second end surface 122 Ab.

The first end surface 122Aa extends radially inward. The first end surface 122Aa is inclined toward one side in the circumferential direction as it goes toward the radially inner side. The second end face 122Ab extends radially inward. The second end surface 122Ab is inclined toward one side in the circumferential direction as it goes toward the radially inner side. That is, the first end surface 122Aa and the second end surface 122Ab are inclined in the same direction with respect to the reference line L as viewed from the axial direction.

As shown in fig. 9, of a pair of core pieces 120P adjacent in the circumferential direction, the second end surface 122Ab of the core piece 120P located on one side in the circumferential direction and the first end surface 122Aa of the core piece 120P located on the other side in the circumferential direction are in contact with each other. That is, in the connecting portion 122 adjacent in the circumferential direction, the end surface 122Aa and the end surface 122Ab of the first arm portion 122A contact each other.

According to the present modification, the end surfaces 122Aa and 122Ab inclined in the same direction in the coupling portions 122 adjacent in the circumferential direction are in contact with each other. Therefore, when a radial force is applied to the single core member 120P in the stator core 120, the end surfaces 122Aa and 122Ab interfere with each other, and the movement of the core member 120P in the radial direction is restricted. As a result, the strength of connection between the core members 120P can be increased.

As shown in fig. 10, the second arm portion 122B has a pair of end surfaces 122Ba and 122Bb facing opposite sides in the circumferential direction, similarly to the first arm portion 122A. Here, one of the pair of end surfaces 122Ba and 122Bb facing one side in the circumferential direction is defined as a third end surface 122Ba, and the other end facing the other side in the circumferential direction is defined as a fourth end surface 122 Bb.

The third end surface 122Ba extends radially inward. The third end surface 122Ba is inclined toward the other side in the circumferential direction as it goes toward the radially inner side. The fourth end surface 122Bb extends radially inward. The fourth end surface 122Bb is inclined toward the other side in the circumferential direction as it goes toward the radially inner side. That is, the third end surface 122Ba and the fourth end surface 122Bb are inclined in the same direction with respect to the reference line L as viewed from the axial direction.

In fig. 9, the first arm portion 122A is indicated by a solid line, and the second arm portion 122B is indicated by a broken line.

As shown in fig. 9, in the coupling portion 122 adjacent in the circumferential direction, the end surfaces 122Ba and 122Bb of the second arm portions 122B contact each other. Therefore, in stator core 120, end surfaces 122Ba and 122Bb of adjacent coupling portions 122 interfere with each other, and movement of core 120P in the radial direction is restricted.

In the present modification, the inclination directions of the end surfaces 122Aa and 122Ab of the first arm portion 122A and the inclination directions of the end surfaces 122Ba and 122Bb of the second arm portion 122B are opposite to each other with respect to the reference line L. Therefore, when a radial force is applied to a single core piece 120P in the stator core 120, the directions of the circumferential directions of the first arm portion 122A and the second arm portion 122B received from the adjacent core pieces 120P are opposite to each other.

Therefore, the movement of the core 120P in the circumferential direction when a force is applied to the core 120P is restricted, and the coupling force of the plurality of cores 120P is improved.

In the present modification, the end surfaces 122Aa, 122Ab, 122Ba, and 122Bb of the first arm portion 122A and the second arm portion 122B are linearly inclined as viewed from the axial direction. However, the end surfaces 122Aa, 122Ab, 122Ba, and 122Bb may be curved surfaces.

The first arm portion 122A and the second arm portion 122B are provided with groove portions 125 at radially inner ends thereof, respectively. The groove portion 125 is elongated in the axial direction. In addition, the groove portion 125 is open on the radially inner side.

In a pair of core pieces 120P adjacent in the circumferential direction, a first arm portion 122A of one core piece 120P and a second arm portion 122B of the other core piece 120P overlap each other as viewed from the axial direction. Further, in the first arm portion 122A and the second arm portion 122B overlapped with each other, the respective groove portions 125 are connected along the axial direction. The connection member 130 is fitted into the groove portion 125 connected in the axial direction.

The connecting member 130 is located radially inward of the coupling portion 122 of the core member 120P. The connecting member 130 connects the first arm portion 122A and the second arm portion 122B of the core member 120P adjacent in the circumferential direction. In the present modification, the connecting member 130 has a rectangular shape as viewed from the axial direction. The connection member 130 is a rod shape elongated in the axial direction.

Groove portion 125 extends across first arm portion 122A and second arm portion 122B of core member 120P adjacent in the circumferential direction. Core pieces 120P adjoining in the circumferential direction are joined to each other by fitting connecting members 130 into groove portions 125.

As shown in fig. 10, the groove portion 125 has a pair of facing surfaces 125 a. The pair of facing surfaces 125a are parallel to each other. The pair of facing surfaces 125a face each other in the circumferential direction. In addition, the pair of facing surfaces extend in the radial direction. The connecting member 130 is sandwiched between the pair of facing surfaces 125 a. Therefore, the distance between the pair of facing surfaces 125a is substantially equal to the dimension of the connecting member 130 orthogonal to the radial direction.

The pair of facing surfaces 125a are inclined at an angle α with respect to the reference line L as viewed from the axial direction. That is, the insertion direction of the connection member 130 with respect to the groove portion 125 is inclined with respect to the extension direction of the tooth portion 121. Therefore, even if a force along reference line L is applied to core piece 120P, connecting member 130 is less likely to fall out of groove portion 125. That is, according to the present modification, the connecting member 130 is less likely to be separated from the core 120P, and the stability of the connection of the core 120P can be improved. In the present modification, the angle α is about 5 °.

Further, the connection member 130 is sandwiched by the pair of facing surfaces 125a from both sides in the circumferential direction in the recessed portion 125. By laminating the electromagnetic steel sheets of the connecting member 130 in the radial direction, the reaction force received by the connecting member 130 from the facing surface 125a can be changed to a direction intersecting the laminating direction of the electromagnetic steel sheets, and separation of the laminated electromagnetic steel sheets can be suppressed. Further, the connection members 130 may be stacked in the circumferential direction. In this case, the connection member 130 is applied with a force in a direction in which the stacked magnetic steel sheets are brought into close contact with each other, and the magnetic steel sheets are prevented from being separated from each other.

As shown by a two-dot chain line in fig. 9, the cylindrical portion 81a of the stator holder 8 is disposed radially inward of the connecting member 130 of the present modification. The outer peripheral surface of the cylindrical portion 81a contacts the connecting member 130 from the radially inner side. The tube portion 81a restricts the movement of the coupling member 130 radially inward, and suppresses the coupling member 130 from coming off the coupling portion 122 of the core 120P. Thereby, the stator holder 8 suppresses the release of the connection between the plurality of core pieces 120P.

Further, the outer peripheral surface of the cylindrical portion 81a applies a force directed radially outward to the coupling portion 122 via the coupling member 130. By applying a radially outward force to the coupling portion 122 through the tube portion 81a, the first end surface 122Aa is pressed against the second end surface 122Ab of the adjacent core 120P, and the fourth end surface 122Bb is pressed against the third end surface 122Ba of the adjacent core 120P. This improves the coupling strength and rigidity of stator core 120.

While the embodiments of the present invention and the modifications thereof have been described above, the respective configurations and combinations thereof are examples, and additions, omissions, substitutions, and other modifications of the configurations may be made without departing from the spirit of the present invention. The present invention is not limited to the embodiments.

Description of the symbols

1: motor with a stator having a stator core

2: stator

7: rotor

8: stator fixer

20. 120: stator core

20P, 120P: core piece

21. 121: toothed section

22. 122: connecting part

22a, 122 Aa: first end face (end face)

22b, 122 Ab: second end face (end face)

23. 123: convex part

24. 124: concave part

25: the first convex strip part

26: second convex strip part

29. 129: through hole (hole part)

30. 130, 130: connecting member

31: body part

32: clamping part

40: coil

81: first holder member

81a, 86 a: barrel part

81b, 86 b: floor part

82. 82A: protrusion part

83: first fixed hole (fixed hole)

85: fixing projection

85 a: riveting part

86: second holder member

90: clamp apparatus

91: retaining protrusion

91 a: pin

122 Ba: third end face (end face)

122 Bb: fourth end face (end face)

122A: a first arm part

122B: second arm part

125: groove part

125 a: facing surface

J: center shaft

L: reference line

α: angle of rotation

Phi 2: second disposition angle

Phi 1: first configuration angle

Claims (27)

1. A stator for an outer rotor motor, comprising:

a plurality of core members arranged in a circumferential direction with respect to the central axis; and

a plurality of connecting members that join two adjacent core pieces of the plurality of core pieces;

the core member has a tooth portion around which a coil is wound, and a coupling portion located on the central axis side of the tooth portion,

the connecting member connects the connecting portions to each other.

2. The stator as set forth in claim 1 wherein said core member has one said tooth and one said joint.

3. The stator according to claim 1 or 2, wherein the number of the core pieces and the connection members is the same as each other.

4. A stator according to any one of claims 1 to 3, wherein the coupling portions adjoining in the circumferential direction are in contact with each other.

5. The stator according to any one of claims 1 to 4, wherein the coupling portion has a pair of end faces that are opposite to each other in a circumferential direction, a convex portion that protrudes from a first end face that is one of the pair of end faces, and a concave portion that is concave in a second end face that is the other of the pair of end faces,

the coupling portions adjoining in the circumferential direction are fixed to each other by the connecting member in a state where the convex portion enters the concave portion.

6. The stator according to any one of claims 1 to 5, wherein the connecting portion has a first ridge portion and a second ridge portion that protrude radially inward and extend in an axial direction,

the connecting member has:

a body portion; and

a pair of clamping portions extending radially outward from the main body;

the pair of holding portions hold the first ridge portion provided on one of the connection portions adjacent to each other in the circumferential direction and the second ridge portion provided on the other.

7. The stator according to claim 6, wherein the connecting member includes electromagnetic steel sheets laminated in an axial direction.

8. The stator according to any one of claims 1 to 5, wherein the coupling portion has a first arm portion and a second arm portion arranged along an axial direction,

the first arm portion is elongated toward a radially inner side,

the second arm portion is elongated toward the radially inner side,

the direction in which the first arm portion extends radially inward is circumferentially offset from the direction in which the second arm portion extends radially inward,

groove portions that extend in the axial direction and open radially inward are provided at radially inward end portions of the first arm portion and the second arm portion, respectively,

in a pair of the core members adjoining in the circumferential direction, the first arm portion of one of the core members and the second arm portion of the other of the core members overlap with each other as viewed from the axial direction, the respective groove portions are connected to each other in the axial direction,

the connecting member is a rod-like member extending in the axial direction, and is fitted into the groove portion connected in the axial direction.

9. The stator according to claim 8, wherein the first arm portion has a pair of end faces facing opposite sides to each other in a circumferential direction,

the pair of end surfaces of the first arm portion extend radially inward and are inclined toward one side in the circumferential direction as they extend radially inward,

the second arm portion has a pair of end surfaces facing opposite sides to each other in a circumferential direction,

the pair of end surfaces of the second arm portion extend radially inward and are inclined toward the other side in the circumferential direction as they extend radially inward,

in the coupling portion adjacent in the circumferential direction, the end surfaces of the first arm portions are in contact with each other, and the end surfaces of the second arm portions are in contact with each other.

10. The stator according to claim 9, wherein the groove portion has a pair of facing surfaces facing each other in a circumferential direction,

the pair of facing surfaces are inclined with respect to a reference line passing through the center of the tooth portion as viewed from the axial direction.

11. The stator according to claim 9 or 10, wherein the connecting member includes electromagnetic steel sheets laminated in a radial direction.

12. The stator according to any one of claims 1 to 5, wherein the coupling portion has a pair of end faces facing opposite sides to each other in a circumferential direction,

the pair of end faces are extended toward the radial inner side and inclined toward one side of the circumferential direction as facing the radial inner side,

the end surfaces of the coupling portions adjacent in the circumferential direction contact each other.

13. The stator according to any one of claims 1 to 12, wherein a plurality of the core pieces and a plurality of the connection members constitute a stator core,

having a stator holder holding the stator core,

the stator holder has a first holder member and a second holder member which are opposed to each other in the axial direction and sandwich the stator core from both sides in the axial direction,

at least one of the plurality of connecting portions has a through hole penetrating in the axial direction,

at least one of the first and second retainer members has at least one protrusion inserted into the through hole.

14. The stator according to claim 13, wherein a plurality of the coupling portions have the through-holes, respectively,

the first and second anchor members have the same number of the protrusions as the through-holes.

15. The stator according to claim 13 or 14, wherein the connecting member is located radially inward with respect to the joint portion,

at least one of the first and second retainer members has a cylindrical portion located radially inward of the plurality of core members and extending in an axial direction,

the outer peripheral surface of the cylindrical portion contacts the connecting member from a radially inner side.

16. A motor, comprising:

the stator of any one of claims 1 to 15; and

and a rotor that surrounds the stator from a radially outer side and rotates around the central shaft.

17. A method for manufacturing a stator for an outer rotor motor, comprising:

a first arrangement step of arranging a plurality of core members in a circumferential direction with respect to a central axis, the plurality of core members being arranged with an angle formed between two adjacent core members and the central axis being a first arrangement angle;

a winding step of winding a coil around the core; and

a second arrangement step of arranging a plurality of the core members at a second arrangement angle in which an angle formed by the center axis and the adjacent two core members is smaller than the first arrangement angle.

18. The manufacturing method of the stator according to claim 17, wherein the core member has a hole portion elongated in an axial direction,

the first arranging step is a step of inserting the holding projections into the hole portion using a jig having a plurality of holding projections arranged at the first arranging angle in the circumferential direction and elongated in the axial direction.

19. The manufacturing method of a stator according to claim 17 or 18, wherein the first arranging step and the winding step are performed for each group of the core pieces that have been classified into two or more, and

a third arranging step of arranging the plurality of groups in a ring shape in the circumferential direction, performed after the second arranging step.

20. The manufacturing method of the stator as claimed in claim 19, comprising a joining step of joining core pieces adjoining in a circumferential direction to each other at the second disposition angle.

21. The manufacturing method of a stator according to claim 20, wherein the joining step has:

a first joining step, performed after the second arranging step, of joining the core pieces adjacent in the circumferential direction to each other in the group; and

a second joining step of joining the core members positioned at the circumferential ends of the adjacent groups to each other, performed after the third arranging step.

22. The manufacturing method of the stator according to claim 20, wherein the joining step is performed after the third arranging step to join the core pieces adjacent in the circumferential direction to each other.

23. The method of manufacturing a stator according to any one of claims 20 to 22, wherein the core member has a tooth portion around which the coil is wound, and a connecting portion located on the central axis side with respect to the tooth portion,

the coupling step is a step of attaching a coupling member to the coupling portions adjacent in the circumferential direction and coupling the coupling members to each other.

24. The manufacturing method of the stator as claimed in claim 23, wherein the core pieces and the connection members are equal in number to each other.

25. The manufacturing method of the stator according to any one of claims 17 to 24, comprising a stator fixing step of mounting a stator holder on a stator core having a plurality of the core pieces arrayed in a circumferential direction at the second arrangement angle,

the stator holder has a first holder member and a second holder member which are opposed to each other in the axial direction and sandwich the stator core from both sides in the axial direction,

the anchor fixing step includes a fastening step of fastening the first anchor member and the second anchor member to each other in an axial direction.

26. The manufacturing method of the stator according to claim 25, wherein the fastening step is a step of fixing the first holder member and the second holder member to each other by caulking.

27. The manufacturing method of the stator according to claim 25 or 26, wherein the core member has a hole portion elongated in an axial direction,

the anchor fixing step includes a protrusion forming step of plastically deforming a portion of at least one of the first anchor member and the second anchor member to form a protrusion, and inserting the protrusion into the hole.

Images