JP2018074638A - Stator, motor, and manufacturing method of stator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stator core which suppresses variations of core pieces from a central axis.SOLUTION: A stator core consists of multiple core pieces 40 that are arrayed in a circumferential direction. An insulator consists of multiple insulator pieces 61 that are provided for each of the core pieces. At least one core piece or insulator piece includes a projection 66 that protrudes in an axial direction. A core piece or an insulator piece that is adjacent to the at least one core piece or insulator piece in the circumferential direction includes a recess 67 or a through-hole. The projection is then fitted into the recess or the through-hole. Further, one core piece is welded with an adjacent core piece.SELECTED DRAWING: Figure 6

Description

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

  2. Description of the Related Art Conventionally, a method for forming an annular stator core by bending a so-called straight core in which a plurality of divided core portions are arranged in a straight line is known when manufacturing a stator used in a motor. About the manufacturing method of the stator using a straight core, it describes in Unexamined-Japanese-Patent No. 2004-357491, for example.

If the straight core is used, the conductive wire can be wound around the teeth in an open state before being bent into an annular shape. Therefore, the coil can be easily formed.
JP 2004-357491 A

  In the method described in Japanese Patent Application Laid-Open No. 2004-357491, a stator core is formed by connecting a plurality of divided core portions having one tooth. Each divided core portion is formed of a laminated steel plate in which electromagnetic steel plates are laminated. At the end in the circumferential direction of the core back of each divided core portion, the electromagnetic steel plates having arc convex portions and the electromagnetic steel plates having arc concave portions are alternately laminated. Adjacent divided core parts are combined by fitting the arcuate convex part and the arcuate concave part with each other (paragraph 0038).

  However, in the method described in Japanese Patent Application Laid-Open No. 2004-357491, the electromagnetic steel plates constituting two adjacent divided core portions are alternately overlapped. For this reason, when bending a some division | segmentation core part in an annular | circular shape, a big frictional force arises between the electromagnetic steel plates which overlap in an axial direction. This frictional force becomes resistance, and it is difficult to bend the plurality of divided core portions into an annular shape. In particular, as the thickness of the stator core increases, the number of electronic steel plates that overlap in the axial direction increases. Therefore, it becomes more difficult to bend the plurality of divided core portions into an annular shape. As a result, in the manufactured stator core, the distance from the central axis of each core piece may vary. Variation in the distance from the central axis of each core piece causes cogging to increase when the motor is driven.

  An object of the present invention is to provide a technique that can easily bend a plurality of core pieces arranged in a straight line and suppress variation in the distance from the central axis of each core piece in a manufactured stator core.

  An exemplary first invention of the present application is a stator used in a motor, and surrounds a central axis in a ring shape, and covers a stator core that is a magnetic body having a plurality of teeth extending in a radial direction, and covers at least a part of the stator core. An insulator made of resin, and the stator core is composed of a plurality of core pieces arranged in a circumferential direction, and the insulator is composed of a plurality of insulator pieces provided for each of the core pieces, and at least one core piece Or the insulator piece has a convex part protruding in the axial direction, the core piece or the insulator piece adjacent to the one core piece or the insulator piece in the circumferential direction has a concave part or a through hole, and the convex part is the concave part. Or it fits in the through hole, the one core piece, Serial and adjacent core pieces are welded.

  An exemplary second invention of the present application is a method for manufacturing a stator used in a motor, in which a) a step of forming a plurality of core pieces having a core back and teeth, and b) a resin insulator covering the core pieces. A step of forming a piece, c) a step of arranging a plurality of the core pieces in a straight line, and d) an axially protruding convex portion of at least one core piece or insulator piece, the one core piece or insulator piece And a step of fitting in a recess of a core piece or an insulator piece adjacent in the circumferential direction, e) a step of bending the plurality of core pieces in an annular shape, and f) a step of welding the one core piece and the adjacent core piece And having.

  According to the first exemplary invention of the present application, adjacent core pieces are connected by fitting the convex portion and the concave portion or the through hole. For this reason, at the time of manufacture of a stator, the connected several core piece can be bent easily cyclically | annularly. Therefore, in the stator core after manufacture, it can suppress that the distance from the central axis of each core piece varies.

  According to the second exemplary invention of the present application, adjacent core pieces are connected by fitting the convex portion and the concave portion or the through hole. For this reason, in the step e), the plurality of core pieces can be easily bent into an annular shape. Therefore, in the stator core after manufacture, it can suppress that the distance from the central axis of each core piece varies.

FIG. 1 is a longitudinal sectional view of a motor. FIG. 2 is a top view of the stator. FIG. 3 is a partial top view of the stator. FIG. 4 is a flowchart showing a manufacturing procedure of the stator. FIG. 5 is a diagram of the state before connection in step S5 as seen from the upper side in the axial direction. FIG. 6 is a diagram of the state before connection in step S5 as seen from the outside in the radial direction. FIG. 7 is a view of the state after connection in step S5 as viewed from the upper side in the axial direction. FIG. 8 is a diagram of the state after connection in step S5 as viewed from the outside in the radial direction. FIG. 9 is a partial top view of the stator during the rotation in step S6. FIG. 10 is a view of a state before connection of the stator according to the modification viewed from the outside in the radial direction. FIG. 11 is a diagram of a state before connection of the stator according to the modification, viewed from the outside in the radial direction. FIG. 12 is a top view of a core piece, an insulator piece, and a coil according to a modification.

  Hereinafter, exemplary embodiments of the present invention will be described with reference to the drawings. In this application, the direction parallel to the central axis of the motor is the “axial direction”, the direction orthogonal to the central axis of the motor is the “radial direction”, and the direction along the arc centered on the central axis of the motor is the “circumferential direction”. , Respectively. Further, in the present application, the shape and positional relationship of each part will be described with the axial direction as the vertical direction and the circuit board side with respect to the stator as the upper side. However, the definition of the vertical direction is not intended to limit the orientation of the motor according to the present invention during manufacture and use.

<1. First Embodiment>
<1-1. Motor structure>
FIG. 1 is a longitudinal sectional view of the motor 1. The motor 1 is a so-called inner rotor type molded motor in which a rotor 32 is disposed on the radially inner side of a stator 21 covered with resin. The motor 1 is used for home appliances such as an air conditioner, for example. However, the motor 1 of the present invention may be used for applications other than home appliances. For example, the motor 1 of the present invention may be mounted on transportation equipment such as automobiles and railways, OA equipment, medical equipment, tools, industrial large equipment, and the like to generate various driving forces.

  As shown in FIG. 1, the motor 1 has a stationary part 2 and a rotating part 3. The stationary part 2 is fixed to a frame of a device to be driven. The rotating part 3 is supported by the stationary part 2 so as to be rotatable around a central axis 9 extending vertically.

  The stationary part 2 of the present embodiment includes a stator 21, a holder part 22, a cover 23, a circuit board 24, a lower bearing part 25, and an upper bearing part 26. The rotating unit 3 includes a shaft 31 and a rotor 32.

  The stator 21 is an armature that generates a magnetic flux in accordance with a drive current supplied from an external power source (not shown) via the circuit board 24. FIG. 2 is a top view of the stator 21. FIG. 3 is a partial top view of the stator 21. As shown in FIGS. 1 to 3, the stator 21 surrounds the central axis 9 extending vertically in an annular shape. The stator 21 includes a stator core 211, an insulator 212, and a plurality of coils 213.

  The stator core 211 is a magnetic body that surrounds the central shaft 9 in an annular shape. The stator core 211 is constituted by a plurality of core pieces 40 arranged in a ring shape in the circumferential direction. In the example of FIG. 2, the number of core pieces 40 constituting the stator core 211 is twelve. Each core piece 40 includes a core back 41 and a tooth 42 that protrudes radially inward from the core back 41. The plurality of core backs 41 are arranged in an annular shape substantially coaxial with the central axis 9. The plurality of teeth 42 are arranged at equal intervals in the circumferential direction. For the stator core 211, for example, a laminated steel plate is used.

  The insulator 212 is attached to the stator core 211. As a material of the insulator 212, a resin which is an insulator is used. The insulator 212 is composed of a plurality of insulator pieces 60 arranged in a ring shape in the circumferential direction. In the example of FIG. 2, the number of insulator pieces 60 constituting the insulator 212 is twelve. The insulator piece 60 is provided for each core piece 40. That is, one insulator piece 60 is attached to one core piece 40. Each insulator piece 60 covers at least a part of the core piece 40. Specifically, each insulator piece 60 covers both end surfaces of the teeth 42 in the axial direction and both surfaces in the circumferential direction.

  The coil 213 includes a conductive wire wound around the teeth 42 via an insulator 212. That is, the insulator 212 is interposed between the tooth 42 and the coil 213. Thereby, the electrical short circuit between the teeth 42 and the coil 213 is prevented. The detailed configuration of the stator 21 will be described later.

  The holder portion 22 is a resin member that holds the stator 21 and the lower bearing portion 25. The holder part 22 includes a wall part 221, a bottom plate part 222, and a lower bearing holding part 223. The wall portion 221 extends in a substantially cylindrical shape in the axial direction. At least a part of the side surfaces of the stator 21 and the insulator 212 is covered with a resin constituting the wall portion 221. However, a part of the stator 21 including the end face on the radially inner side of the teeth 42 is exposed from the wall portion 221. Further, a rotor 32 described later is disposed inside the wall portion 221 in the radial direction.

  The bottom plate portion 222 spreads in a plate shape from the lower end of the wall portion 221 toward the radially inner side. The bottom plate portion 222 is located on the lower side in the axial direction than the stator 21 and the rotor 32. The lower bearing holding part 223 extends from the inner end of the bottom plate part 222 and covers a part of the lower bearing part 25. The lower bearing portion 25 and the lower end portion of the shaft 31 are disposed on the radially inner side of the lower bearing holding portion 223.

  The cover 23 is located above the holder part 22 and covers the opening above the holder part 22. The circuit board 24 and the rotor 32 are accommodated in a housing constituted by the holder portion 22 and the cover 23. The cover 23 has an upper plate portion 231 and an upper bearing holding portion 232. The upper plate portion 231 extends substantially perpendicular to the central axis 9 on the upper side in the axial direction from the stator 21, the holder portion 22, the circuit board 24, and the rotor 32. The upper bearing holding portion 232 extends from the inner end of the upper plate portion 231 and covers a part of the upper bearing portion 26. The upper bearing portion 26 and a part of the shaft 31 are disposed on the radially inner side of the upper bearing holding portion 232.

  Note that the cover 23 of the present embodiment is made of resin. The resin cover 23 can be efficiently manufactured by molding using a mold. In addition, the occurrence of the electrolytic corrosion phenomenon in the upper bearing portion 26 can be suppressed as compared with the case where a metal cover is used.

  The circuit board 24 is held by the holder portion 22 and is disposed substantially perpendicular to the central axis 9. The circuit board 24 is accommodated in a housing constituted by the holder portion 22 and the cover 23. The circuit board 24 is disposed above the stator 21 and the rotor 32. The coil 213 of the stator 21 and the circuit board 24 are electrically connected via terminal pins 27 fixed to the insulator 212. In FIG. 2, the terminal pins 27 are not shown.

  A connection hole 201 is provided in a part in the circumferential direction between the holder portion 22 and the cover 23. The lead wire 241 extending from the circuit board 24 passes through the connection hole 201 and is drawn out of the holder portion 22. Then, the end of the lead wire 241 is connected to an external power source. The current supplied from the external power source flows to the coil 213 through the lead wire 241, the circuit board 24, and the terminal pin 27.

  The lower bearing portion 25 supports the shaft 31 to be rotatable below the rotor 32. The upper bearing portion 26 rotatably supports the shaft 31 above the rotor 32. For the lower bearing portion 25 and the upper bearing portion 26 of the present embodiment, ball bearings that rotate the outer ring and the inner ring relative to each other via a sphere are used. The outer ring of the lower bearing portion 25 is fixed to the lower bearing holding portion 223 of the holder portion 22. The outer ring of the upper bearing portion 26 is fixed to the upper bearing holding portion 232 of the cover 23. The inner rings of the lower bearing portion 25 and the upper bearing portion 26 are fixed to the shaft 31. However, other types of bearings such as a slide bearing and a fluid bearing may be used for the lower bearing portion 25 and the upper bearing portion 26 in place of the ball bearing.

  The shaft 31 is a columnar member that extends through the rotor 32 in the axial direction. The shaft 31 rotates about the central axis 9. The upper end portion of the shaft 31 protrudes upward from the holder portion 22 and the cover 23. For example, a fan for an air conditioner is attached to the upper end portion of the shaft 31. However, the upper end portion of the shaft 31 may be coupled to a drive unit other than the fan via a power transmission mechanism such as a gear.

  The rotor 32 is a member that is fixed to the shaft 31 and rotates together with the shaft 31. The rotor 32 is disposed inside the stator 21 in the radial direction. The rotor 32 of the present embodiment is an annular member formed of a plastic resin mixed with a magnet. As shown in FIG. 1, the rotor 32 includes an inner cylinder part 321, an outer cylinder part 322, and a connection part 323.

  The inner cylinder part 321 is a substantially cylindrical part fixed to the shaft 31. A spiral groove 311 is provided on at least a surface of the outer peripheral surface of the shaft 31 that is fixed to the inner cylindrical portion 321. The rotor 32 is formed by injection molding using the shaft 31 as an insert part. At the time of injection molding, the resin in a fluid state flows into a groove 311 provided on the outer peripheral surface of the shaft 31. Thereby, the rotor 32 is firmly fixed to the shaft 31. Further, relative rotation of the rotor 32 with respect to the shaft 31 is suppressed when the motor 1 is driven.

  The outer cylinder part 322 is a substantially cylindrical part located radially outside the inner cylinder part 321. The outer peripheral surface of the outer cylindrical portion 322 is a magnetic pole surface, and faces the end surface on the radially inner side of the tooth 42 in the radial direction with a slight gap. The connection part 323 is a disk-shaped part that connects the inner cylinder part 321 and the outer cylinder part 322. The thickness in the radial direction of the inner cylindrical portion 321 and the outer cylindrical portion 322 is the largest in the vicinity of the boundary with the connecting portion 323. Moreover, the radial thickness of the inner cylinder part 321 and the outer cylinder part 322 is gradually reduced toward both ends in the axial direction.

  In the present embodiment, a rotor 32 made of plastic resin mixed with a magnet is used. However, the rotor may be one in which a plurality of magnets are arranged on the outer peripheral surface of a cylindrical rotor core that is a magnetic body. Alternatively, the rotor may be one in which a plurality of axial holes are provided in a magnetic rotor core, and a magnet is disposed in the holes.

  When the motor 1 is driven, a drive current is supplied to the coil 213 from an external power source via the lead wire 241, the circuit board 24, and the terminal pin 27. Thereby, magnetic flux is generated in the plurality of teeth 42 of the stator core 211. A circumferential torque is generated by the action of the magnetic flux between the teeth 42 and the rotor 32. As a result, the rotating unit 3 rotates about the central axis 9.

<1-2. Structure of stator>
Next, a detailed configuration of the stator 21 will be described while explaining a manufacturing procedure of the stator 21. FIG. 4 is a flowchart showing a manufacturing procedure of the stator 21.

  When manufacturing the stator 21, the linear stator 21 is first produced (steps S1-S5). Then, the linear stator 21 is bent into an annular shape (step S6), and necessary portions are welded (step S7). Thereby, the annular stator 21 shown in FIG. 2 can be obtained. Thereafter, a molding process for covering the stator 21 with resin is performed (step S8). Hereinafter, details of each process will be described.

  As shown in FIG. 4, when the stator 21 is manufactured, first, a plurality of core pieces 40 each having a core back 41 and teeth 42 are formed (step S1). The stator core 211 of the present embodiment has a plurality of core piece groups 50 constituted by two or more connected core pieces 40. Specifically, as shown in FIG. 2, the stator core 211 has three core piece groups 50. Each core piece group 50 includes four core pieces 40.

  In step S <b> 1, the core piece group 50 including the four core pieces 40 is formed by punching the electromagnetic steel plates and stacking the punched electromagnetic steel plates in the axial direction. In the core piece group 50 formed in step S1, the four core backs 41 are arranged in a straight line. Accordingly, the four teeth 42 included in the core piece group 50 each extend in a direction orthogonal to the arrangement direction of the core backs 41.

  Here, the arrangement direction of the core backs 41 is a direction that becomes the circumferential direction when the core back 41 is bent into an annular shape in the subsequent step S6. For this reason, also in the following description to step S5, the arrangement direction of the core back 41 is referred to as a circumferential direction. Further, the teeth 42 side with respect to the core back 41 is referred to as a radially inner side, and the opposite side is referred to as a radially outer side.

  Next, the insulator 212 is injection-molded using the plurality of core pieces 40 as insert parts (step S2). In step S2, first, the core piece group 50 is disposed as an insert part inside the pair of molds. Then, the molten resin is poured into the mold to cure the molten resin. Thereby, the insulator piece 60 is molded for each core piece group 50. Each core piece 40 included in the core piece group 50 is covered with a resin insulator piece 60.

  As shown in FIG. 1, the insulator piece 60 includes an upper cover portion 61, a lower cover portion 62, a teeth cover portion 63, and a flange portion 64. The upper cover portion 61 covers the upper surface of the core back 41. The lower cover portion 62 covers the lower surface of the core back 41. The teeth cover portion 63 covers the upper and lower surfaces of the teeth 42 and both side surfaces in the circumferential direction. The collar portion 64 extends vertically from the radially inner end of the teeth cover portion 63.

  Subsequently, the plurality of core pieces 40 are arranged linearly (step S3). Specifically, twelve core pieces 40 are arranged such that the core backs 41 are arranged in a straight line. In the present embodiment, the three core piece groups 50 are arranged at positions where the respective core backs 41 are arranged in a straight line.

  Here, let the three core piece groups 50 be the 1st core piece group 51, the 2nd core piece group 52, and the 3rd core piece group 53 in order toward the circumferential direction other side from the circumferential direction one side. In addition, the four core pieces 40 forming each core piece group 51, 52, 53 are sequentially arranged from one circumferential side to the other circumferential side in order from the first core piece 401, the second core piece 402, the third core piece 403, and The fourth core piece 404 is assumed.

  At least a part of the radially outer surface of the core back 41 of each core piece 40 slightly protrudes radially outward. Moreover, the end surfaces 412 on both sides in the circumferential direction of the core back 41 are flat surfaces that are inclined with respect to the extending direction of the teeth 42. At the time of step S3, the space | interval of the adjacent end surface 412 leaves | separates gradually as it goes to a radial inside from a radial direction outer side.

  The other end in the circumferential direction and the radially outer end of the core back 41 of the first core piece 401 and the one end in the circumferential direction and the radially outer end of the core back 41 of the second core piece 402 are the electrical steel sheet itself. Are connected. Similarly, the other end in the circumferential direction and the radially outer end of the core back 41 of the second core piece 402 and the one end in the circumferential direction and the radially outer end of the core back 41 of the third core piece 403 are: The electromagnetic steel sheet itself is connected. Further, the other circumferential end and the radial outer end of the core back 41 of the third core piece 403 and the one circumferential end and the radial outer end of the core back 41 of the fourth core piece 404 are electromagnetic The steel plates themselves are connected.

  Thereafter, a conductive wire is wound around each tooth 42 via the tooth cover portion 63 of the insulator 212 (step S4). The conductive wire forms a coil 213 for each tooth 42. Further, the insulator pieces 60 are connected to each other at the boundary portion between the core piece groups 50 adjacent in the circumferential direction (step S5). Note that the order of step S4 and step S5 may be reversed.

  FIG. 5 is a diagram of the state before connection in step S5 as seen from the upper side in the axial direction. FIG. 6 is a diagram of the state before connection in step S5 as seen from the outside in the radial direction. FIG. 7 is a view of the state after connection in step S5 as viewed from the upper side in the axial direction. FIG. 8 is a diagram of the state after connection in step S5 as viewed from the outside in the radial direction.

  As shown in FIGS. 5 and 6, the insulator piece 60 that covers the fourth core piece 404 of each core piece group 50 has a pair of protruding pieces 65. The pair of projecting pieces 65 includes an upper projecting piece 65a extending from the end portion on the other side in the circumferential direction of the upper cover portion 61 and an end portion on the other side in the circumferential direction of the lower cover portion 62, And a lower protruding piece 65b extending toward the other side in the circumferential direction. Each protruding piece 65 has a convex portion 66 protruding in the axial direction. Specifically, the upper protruding piece 65a has an upper convex portion 66a that protrudes downward from the lower surface. The lower protruding piece 65b has a lower convex portion 66b protruding upward from the upper surface.

  As shown in FIGS. 5 and 6, the insulator piece 60 that covers the first core piece 401 of each core piece group 50 has a pair of recesses 67. The pair of recesses 67 are recessed upward from an upper recess 67a that is recessed downward from the upper surface near the end of one side in the circumferential direction of the upper cover 61 and an upper surface of the lower cover 62 that is near the end of one side in the circumferential direction. And a lower recess 67b.

  In step S5, the adjacent core piece groups 50 are moved closer to each other in the circumferential direction as indicated by the white arrows in FIGS. If it does so, the edge part of the circumferential direction one side of the adjacent insulator piece 60 will be inserted between the upper side protrusion piece 65a and the lower side protrusion piece 65b. And the upper side convex part 66a of the upper side protrusion piece 65a fits into the upper side recessed part 67a. Further, the lower convex portion 66b of the lower protruding piece 65b fits into the lower concave portion 67b. As a result, as shown in FIGS. 7 and 8, the insulator pieces 60 are connected to each other at the boundary portion between the core piece groups 50 adjacent in the circumferential direction. As a result, a linear stator 21 is obtained.

  In particular, in this embodiment, not the core piece 40 but the insulator piece 60 is provided with the convex portion 66 and the concave portion 67. For this reason, the convex part 66 and the recessed part 67 can be easily shape | molded at the time of the insert molding of step S2 mentioned above.

  Subsequently, the linear stator 21 is bent into an annular shape (step S6). Specifically, the connecting portions of adjacent core pieces 40 included in each core piece group 50 are bent. Further, as described above, the adjacent insulator pieces 60 are connected to each other at the boundary between the core piece groups 50 adjacent in the circumferential direction by fitting the convex portions 66 and the concave portions 67 together. For this reason, in the boundary part of the core piece group 50 adjacent to the circumferential direction, the convex part 66 and the recessed part 67 rotate, maintaining a fitting state. Thereby, the core piece 40 adjacent to the circumferential direction can be easily bent in the boundary part of the core piece group 50 adjacent to the circumferential direction. Therefore, in the stator 21 after manufacture, it can suppress that the distance from the central axis 9 of each core piece 40 varies.

  FIG. 9 is a partial top view of the stator 21 during the rotation in step S6. As shown in FIG. 9, when the plurality of core pieces 40 are bent in an annular shape, the end faces 412 of the core backs 41 adjacent in the circumferential direction come into contact with each other. As described above, by bringing the flat end surfaces 412 of the adjacent core backs 41 into contact with each other, the plurality of core pieces 40 can be accurately arranged. Therefore, in the stator core 211 after manufacture, it can suppress more that the distance from the central axis 9 of each core piece 40 varies.

  Moreover, as shown in FIG. 9, in this embodiment, the shape when it sees in the axial direction of the convex part 66 is circular. For this reason, when the convex part 66 is rotated with respect to the concave part 67 in step S6, the convex part 66 can be prevented from being caught by the concave part 67.

  As shown in FIG. 9, in the present embodiment, the core piece 40 rotates around a portion other than the convex portion 66 and the concave portion 67 at the boundary portion between the core piece groups 50 adjacent in the circumferential direction. The concave portion 67 extends in a slit shape along the direction in which the convex portion 66 moves when the core piece 40 rotates. For this reason, when the plurality of core pieces 40 are bent into an annular shape, the convex portion 66 can be smoothly moved relative to the concave portion 67.

  Thereafter, the core pieces 40 are welded to each other (step S7). Specifically, as indicated by a two-dot chain line in FIG. 8, circumferential ends of the radially outer surface of the core back 41 are welded to each other at the boundary between adjacent core piece groups 50. Moreover, the edge part of the circumferential direction of the surface of the radial direction outer side of the several core back 41 contained in each core piece group 50 may be further welded. Thus, a part of the boundary part of the core back 41 is welded, whereby the adjacent core backs 41 are more firmly connected.

  After the welding process in step S7 is completed, a molding process for covering the stator 21 including the stator core 211, the insulator 212, and the coil 213 with a resin is performed (step S8). Specifically, the holder part 22 which is a resin mold part is molded by performing injection molding using the stator 21 as an insert part. Thus, by covering the stator 21 with the resin constituting the holder portion 22, it is possible to suppress the positional deviation of each core piece 40 after the motor 1 is manufactured.

  The stator 21 is formed by the above steps S1 to S8.

  The motor 1 is a three-phase motor driven by a three-phase alternating current of U phase, V phase, and W phase. Further, as described above, the core piece group 50 of the present embodiment includes the four core pieces 40. That is, in the present embodiment, the number “4” of the core pieces 40 included in the core piece group 50 is different from the number “3” of the phases of the motor 1. Thus, in a multiphase motor, if the number of core pieces 40 included in the core piece group 50 is less than the number of phases of the motor 1, the number of connecting portions by the convex portions 66 and the concave portions 67 can be reduced. Thereby, the strength when the stator 21 is bent into an annular shape can be improved.

<2. Modification>
As mentioned above, although exemplary embodiment of this invention was described, this invention is not limited to said embodiment.

  FIG. 10 is a diagram of a state before connection of the stator according to a modification, viewed from the outside in the radial direction. In the example of FIG. 10, the insulator piece 60 </ b> A having the concave portion 67 </ b> A has a guide surface 68 </ b> A at the circumferential edge on the insulator piece 60 </ b> A side having the convex portion 66 </ b> A. The guide surface 68A overlaps the convex portion 66A and the concave portion 67A in the circumferential direction. The guide surface 68A is an inclined surface that is inclined with respect to the circumferential direction. Specifically, the guide surface 68A is inclined from the circumferential edge of the insulator piece 60A so as to gradually approach the axial edge as it approaches the recess 67A.

  In step S5, when connecting the insulator pieces 60A adjacent to each other in the circumferential direction, the adjacent core piece groups 50A are moved closer to each other in the circumferential direction as indicated by white arrows in FIG. Then, the convex portion 66A is guided to the insertion port of the concave portion 67A along the guide surface 68A. Therefore, the convex portion 66A can be more easily fitted into the concave portion 67A.

  FIG. 11 is a view of a state before connection of stators according to another modification as viewed from the outside in the radial direction. In the example of FIG. 11, the pair of protruding pieces 65B protruding in the circumferential direction has a through hole 69B. Each through-hole 69B penetrates the protruding piece 65B in the axial direction. On the other hand, the insulator piece 60B having the protruding piece 65B and the insulator piece 60B adjacent in the circumferential direction have a pair of convex portions 66B. Each convex portion 66B protrudes in the axial direction from the end surface in the axial direction near the end portion in the circumferential direction of the insulator piece 60B.

  In step S5, when connecting the insulator pieces 60B adjacent in the circumferential direction, the adjacent core piece groups 50B are made to approach in the circumferential direction as indicated by the white arrows in FIG. If it does so, the edge part of the circumferential direction one side of adjacent insulator piece 60B will be inserted between a pair of protrusion pieces 65B. And each convex part 66B fits in the through-hole 69B. Thereby, the insulator pieces 60B are connected to each other at the boundary portion between the adjacent core piece groups 50B.

  In the above embodiment, a through hole may be provided in the insulator piece 60 in place of the recess 67. Further, in the modification of FIG. 11, a pair of protruding pieces 65B may be provided with a recess instead of the through hole 69B.

  FIG. 12 is a top view of a core piece 40C, an insulator piece 60C, and a coil 213C according to another modification. In the example of FIG. 12, the plurality of core pieces 40C are each a single member without forming a core piece group. An insulator piece 60C is provided for each core piece 40C. Each insulator piece 60C is provided with a convex portion 66C and a concave portion 67C. If it does in this way, the bending operation | work of step S6 will become easy in the boundary part of all the insulator pieces 60C. Therefore, in the stator after manufacture, it can suppress that the distance from the central axis of each core piece 40C varies.

  In the example of FIG. 12, each insulator piece 60C has a convex portion 66C at one end in the circumferential direction and a concave portion 67C at the other end in the circumferential direction. If it does in this way, shape of insulator piece 60C can be made into one kind. Further, by connecting the insulator pieces 60C having the same shape in the circumferential direction, it is possible to easily form a continuous insulator.

  Moreover, in said embodiment and modification, at least 1 insulator piece had a convex part, and the insulator piece adjacent to the said insulator piece in the circumferential direction had a recessed part or a through-hole. However, at least one core piece may have a convex portion, and the core piece adjacent to the core piece in the circumferential direction may have a concave portion or a through hole.

  Moreover, in said embodiment, the insulator was a resin molded product which uses a stator core as an insert component. However, an insulator may be molded separately from the stator core, and the molded insulator may be attached to the stator core.

  Moreover, about the detailed shape of each member, you may differ from the shape shown by each figure of this application. Moreover, you may combine suitably each element which appeared in said embodiment and modification in the range which does not produce inconsistency.

  The present invention can be used in, for example, a stator, a motor, and a method for manufacturing a stator.

DESCRIPTION OF SYMBOLS 1 Motor 2 Static part 3 Rotating part 9 Central axis 21 Stator 22 Holder part 23 Cover 24 Circuit board 25 Lower bearing part 26 Upper bearing part 27 Terminal pin 31 Shaft 32 Rotor 40, 40C Core piece 41 Core back 42 Teeth 50, 50A, 50B Core piece group 60, 60A, 60B Insulator piece 65, 65B Protruding piece 66, 66A, 66B, 66C Convex part 67, 67A, 67C Concave part 68A Guide surface 69B Through hole 211 Stator core 212 Insulator 213, 213C Coil

Claims (15)

A stator used in a motor,
A stator core that is a magnetic body having a plurality of teeth surrounding the central axis in an annular shape and extending in the radial direction;
A resin insulator covering at least a part of the stator core;
Have
The stator core is composed of a plurality of core pieces arranged in the circumferential direction,
The insulator is composed of a plurality of insulator pieces provided for each core piece,
At least one core piece or insulator piece has a convex portion protruding in the axial direction;
The core piece or insulator piece that is circumferentially adjacent to the one core piece or insulator piece has a recess or a through hole,
The convex portion fits into the concave portion or the through hole,
The stator in which the one core piece and the adjacent core piece are welded. The stator according to claim 1,
The one insulator piece has the convex portion,
The stator in which the adjacent insulator piece has the recess or the through hole. The stator according to claim 2,
The one insulator piece has a protruding piece protruding in the circumferential direction,
The protruding piece has the convex portion,
The stator in which the adjacent insulator piece has the recess or the through hole. The stator according to claim 2,
The one insulator piece has a protruding piece protruding in the circumferential direction,
The protruding piece has the recess or the through hole,
The stator in which the adjacent insulator piece has the convex portion. The stator according to any one of claims 2 to 4, wherein
The adjacent insulator piece has a guide surface at a circumferential edge on the one insulator piece side,
The stator is a stator that is an inclined surface that overlaps the convex portion and the concave portion in the circumferential direction and is inclined with respect to the circumferential direction. The stator according to any one of claims 1 to 5, wherein
The stator has a circular shape when viewed in the axial direction of the convex portion. The stator according to any one of claims 1 to 6, wherein
The said recessed part or the said through-hole is a stator which is a slit shape extended along the direction in which the said convex part moves, when the said several core piece is bend | folded annularly. The stator according to any one of claims 1 to 7,
The core piece is
Core back and
Teeth projecting radially inward from the core back;
Have
A stator in which circumferential ends of the radially outer surface of the core back are welded to each other. A stator according to any one of claims 2 to 5,
Each of the plurality of insulator pieces has the convex portion at one end in the circumferential direction and has the concave portion at the other end in the circumferential direction. The stator according to any one of claims 1 to 8,
The stator core is
Having a plurality of core piece groups composed of two or more core pieces;
The two or more core pieces included in the core piece group are connected,
The one core piece belongs to one of the two core piece groups adjacent in the circumferential direction,
The adjacent core piece is a stator belonging to the other of the two core piece groups adjacent in the circumferential direction. The stator according to claim 10, wherein
The motor is a multiphase motor;
A stator in which the number of core pieces included in the core piece group is different from the number of phases of the multiphase motor. The stator according to any one of claims 1 to 11, wherein
A conducting wire wound around the teeth via the insulator;
A resin mold portion covering the stator core, the insulator, and the conductive wire;
A stator further comprising: A stator according to any one of claims 1 to 12,
A rotor having a plurality of teeth facing the teeth in the radial direction and supported rotatably about the central axis;
Having a motor. A method of manufacturing a stator used in a motor,
a) forming a plurality of core pieces having a core back and teeth;
b) forming a resin insulator piece covering the core piece;
c) arranging the plurality of core pieces in a straight line;
d) a step of fitting an axially protruding convex portion of at least one core piece or insulator piece into a concave portion of the core piece or insulator piece adjacent to the one core piece or insulator piece in the circumferential direction;
e) a step of bending the plurality of core pieces into an annular shape;
f) welding the one core piece and the adjacent core piece;
A manufacturing method comprising: The manufacturing method according to claim 14,
After step g)
g) The manufacturing method which further has the process of covering the said core piece and the said insulator piece with resin.

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