JP2014158322A - Stator, motor and method of manufacturing stator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stator which allows for enhancement of the yield.SOLUTION: A stator 13a comprises: an annular stator core 14 where first claw-poles 21 and second claw-poles 22 are provided alternately at an equal interval in the circumferential direction; and a coil 15 arranged between the first and second claw-poles 21, 22 in the axial direction, and the first and second claw-poles 21, 22 function as magnetic poles different from each other, on the basis of the electrification of the coil 15. The stator core 14 is constituted by annularly shaping a die-cutting material, obtained by shaping the first and second claw-poles 21, 22 integrally, and then coupling both ends (first and second ends 31a, 31b) of the die-cutting material.

Description

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

  As a stator used in a motor, for example, as shown in Patent Document 1, annular stator cores having a plurality of claw-shaped magnetic poles in the circumferential direction are used in pairs, and the claw-shaped magnetic poles of the pair of stator cores are alternately arranged in the circumferential direction. A so-called Landel type stator is known in which a coil portion is arranged between the pair of stator cores in the axial direction so that the claw-shaped magnetic poles function as different magnetic poles. Incidentally, the Landel-type stator disclosed in Patent Document 1 has a three-stage structure using three pairs of stator cores and coil portions.

JP 2007-181303 A

  By the way, in the stator as described above, it is possible to configure the stator core with a powder magnetic core formed by compression molding a material containing magnetic powder. In this case, a fine shape is formed due to restrictions such as press pressure. There are problems such as being difficult to remove and easy to chip after compaction. Therefore, as a method for solving this problem, a method of forming a stator core by press punching a steel plate can be considered, but in this case, the material inside the annular stator core is wasted, and the yield is poor. There was room for improvement.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a stator, a motor, and a stator manufacturing method capable of improving yield.

  A stator that solves the above problems is arranged between an annular stator core in which first claw-shaped magnetic poles and second claw-shaped magnetic poles are alternately provided at equal intervals in the circumferential direction, and between the first and second claw-shaped magnetic poles in the axial direction. And the first and second claw-shaped magnetic poles function as different magnetic poles based on energization of the coil portion, and the stator core has the first and second claw-shaped A punching material in which magnetic poles are integrally formed is formed in an annular shape, and both ends of the punching material are connected to each other.

  According to this configuration, the stator core is formed by punching a punching material integrally formed with the first and second claw-shaped magnetic poles from a steel plate, rounding the punching material into an annular shape, and connecting both ends thereof. As a result, it is not necessary to make the punching die of the punching material constituting the stator core into an annular shape, so that waste of the steel plate can be reduced, and as a result, the yield can be improved.

  In the stator, the stator core has a core back portion that forms an outer periphery thereof, and the first and second claw-shaped magnetic poles each have a first extending portion extending from the core back portion to the inner peripheral side. It is preferable that the second extending portion extending in the axial direction from the inner peripheral end portion of the first extending portion is bent.

According to this configuration, the first and second claw-shaped magnetic poles can be suitably integrally formed on the stator core. Moreover, it becomes possible to earn an opposing area with a rotor by the 2nd extension part of each claw-shaped magnetic pole.
In the stator, it is preferable that a hole or a notch is formed in a corner portion formed by the core back portion and the first extension portion.

According to this structure, a 1st extension part can be easily bend-formed with respect to the core back part which comprises the outer periphery of a stator core.
In the stator, it is preferable that a hole or a notch is formed in a corner portion formed by the first extension portion and the second extension portion.

  According to this configuration, the inner peripheral surface (the surface facing the rotor) of the second extension portion can be easily formed in an arc shape, and the outer peripheral surface of the rotor can be formed by making the inner peripheral surface of the second extension portion an arc shape. The air gap between the surfaces can be configured uniformly, and as a result, the motor quality can be improved.

Moreover, the motor which solves the said subject is a motor provided with the said stator.
According to this configuration, it is possible to provide a motor with a high yield.
Further, a stator manufacturing method that solves the above problems includes an annular stator core in which first claw-shaped magnetic poles and second claw-shaped magnetic poles are alternately provided at equal intervals in the circumferential direction, and the first and second claw-shaped magnetic poles. And a coil portion disposed between the axial directions, and a stator manufacturing method in which the first and second claw-shaped magnetic poles function as different magnetic poles based on energization of the coil portion, A punching process in which a punching material having a second claw-shaped magnetic pole is integrally punched from a steel sheet; an annularization process in which, after the punching process, the punching material is formed into an annular shape, and both ends of the punching material are connected to each other; A bending step of bending the first and second claw-shaped magnetic poles integrally formed on the material.

  According to this manufacturing method, since the stator core is formed by circularizing the punching material, it is not necessary to make the punching die of the punching material constituting the stator core annular, so that it is possible to reduce the waste of the steel plate. As a result, the yield can be improved.

  According to the stator and the motor of the present invention, the yield can be improved.

It is a perspective view of the motor of an embodiment. It is a perspective view which shows the single stator of the same form. It is a schematic diagram for demonstrating the manufacture aspect of the stator core of the same form. It is a perspective view which shows the single stator of another example. It is a schematic diagram for demonstrating the manufacture aspect of the stator core of another example. It is a perspective view which shows the single stator of another example. It is a schematic diagram for demonstrating the manufacture aspect of the stator core of another example.

Hereinafter, an embodiment of the motor will be described.
FIG. 1 is an overall perspective view of a brushless motor M according to this embodiment, and an annular stator 13 fixed to a motor housing (not shown) is disposed outside a rotor 12 fixed to a rotating shaft 11. . The brushless motor M includes three single motor units stacked in the axial direction, and is configured from the top in the order of a U-phase motor unit Mu, a V-phase motor unit Mv, and a W-phase motor unit Mw. Each phase motor unit Mu, Mv, Mw is composed of a single stator 13a and a single rotor 12a (only the U-phase rotor is shown in FIG. 1). The stator 13 is composed of each single stator 13a, and the rotor 12 is composed of each single rotor 12a.

As shown in FIG. 2, the single stator 13 a includes an annular stator core 14 and a coil portion 15 disposed inside the stator core 14.
The stator core 14 is formed by bending a predetermined portion after punching out an electromagnetic steel sheet with a press. The number of stator cores 14 is equal to the number of first claw-shaped magnetic poles 21 and the number of the first claw-shaped magnetic poles 21 provided in the circumferential direction at equal intervals (12 in this embodiment). It is comprised from the 2nd nail | claw-shaped magnetic pole 22 arrange | positioned between, and the core back part 23 which connects the 1st and 2nd nail | claw-shaped magnetic poles 21 and 22 adjacent to the circumferential direction.

  The first claw-shaped magnetic pole 21 has a first extending portion 21 a that forms a flat portion perpendicular to the axis of the rotating shaft 11. The first extending portion 21a has a V-shape that opens toward the outer peripheral side when viewed in the axial direction, and the second extending portion that extends to one side in the axial direction is formed at the inner peripheral end of the first extending portion 21a. The portion 21b is bent.

  The second claw-shaped magnetic pole 22 has the same shape as the first claw-shaped magnetic pole 21, and a first extending portion 22 a that forms a flat portion perpendicular to the axis of the rotating shaft 11, and the first extending portion 22 a A second extending portion 22b extending in the axial direction from the inner peripheral end portion.

  The second extending portions 21b and 22b of the first and second claw-shaped magnetic poles 21 and 22 extend in directions facing each other and are alternately arranged at equal intervals in the circumferential direction. The second extending portions 21b and 22b constitute the inner periphery of the stator core 14, and the inner peripheral surfaces of the second extending portions 21b and 22b face the rotor 12 in the radial direction. Each of the second extending portions 21b and 22b has a trapezoidal shape that becomes narrower toward the distal end when viewed in the radial direction, and is formed so as not to interfere with each other. In addition, the inner peripheral surfaces of the second extending portions 21 b and 22 b are formed in an arc shape centered on the axis of the rotating shaft 11.

  The first extending part 21a of the first claw-shaped magnetic pole 21 and the first extending part 22a of the second claw-shaped magnetic pole 22 are adjacent to each other in the circumferential direction, and the end on the outer peripheral side is viewed in the axial direction. While wrapping (overlapping), the wrapping portions are connected to each other at the core back portion 23. The core back portion 23 is formed so as to be connected to each of the V-shaped open ends (a pair) of the first extending portions 21 a and 22 a and constitutes the outer periphery of the stator core 14. Further, the first extending portion 21a of the first claw-shaped magnetic pole 21 extends from the one end in the axial direction of the core back portion 23 (the upper end in FIG. 2) to the inner peripheral side, and the other axial end of the core back portion 23 in the axial direction (see FIG. 2, the first extending portion 22 a of the second claw-shaped magnetic pole 22 extends to the inner peripheral side. The first extending portions 21a and 22a of the claw-shaped magnetic poles 21 and 22 are bent with respect to the core back portion 23, and the core back portion 23 and the first extending portions 21a and 22a A cutout portion 25 is formed in the corner portion 24 formed by.

  Between the first claw-shaped magnetic pole 21 and the second claw-shaped magnetic pole 22, an annular coil portion 15 centering on the axis of the rotating shaft 11 is disposed. The coil portion 15 is positioned between the first extending portion 21a of the first claw-shaped magnetic pole 21 and the first extending portion 22a of the second claw-shaped magnetic pole 22 in the axial direction, and the core back portion in the radial direction. 23 and the second extending portions 21b and 22b. The coil portion 15 and the stator core 14 are electrically insulated by a coil bobbin (not shown) interposed therebetween. Further, the lead terminal (not shown) of the coil portion 15 is led out from the cutout portion 25.

  The motor portions Mu, Mv, Mw of each phase have the stator 13a having the above-described configuration, and the stator 13a of each phase causes the first and second claw-shaped magnetic poles 21, 22 to be connected to the coil portion 15 by energization. The stator is a so-called Randel type (claw pole type) structure having 24 poles that are excited by different magnetic poles. The stators 13a of each phase are stacked in the axial direction while shifting the phase by 60 degrees in electrical angle. And the alternating voltage of a phase corresponding to the coil part 15 of the stator 13a of each phase is respectively applied, a rotating magnetic field is generated and the rotor 12 rotates.

  In the present embodiment, a so-called Landel type rotor composed of a pair of rotor cores 26 having claw-shaped magnetic poles 26a and field magnets 27 is adopted as the rotors 12a of the motor portions Mu, Mv, Mw of the respective phases. (See FIG. 1).

[Method for manufacturing stator core]
Next, the manufacturing method and operation of the stator core 14 of this embodiment will be described.
As shown in FIG. 3, first, a plurality of punched materials 31 are punched from a magnetic steel sheet 30 by a press (punching process). At this time, the first and second claw-shaped magnetic poles 21 and 22 and the core back portion 23 are integrally formed on the punching material 31. Each first claw-shaped magnetic pole 21 is formed such that its tip (second extending portion 21a) faces in the same direction, and each second claw-shaped magnetic pole 22 has the same tip (second extending portion 22a). It is formed so as to face the direction (the direction opposite to the first claw-shaped magnetic pole 21). When punching a plurality of punching materials 31 from the electromagnetic steel sheet 30 as in the present embodiment, each second claw-shaped magnetic pole 22 is disposed between each first claw-shaped magnetic pole 21 of the adjacent punching material 31. Thus, it is desirable to set a punching die in terms of yield improvement.

  In addition, the first extending portions 21a and 22a are located at the boundary portion B1 (the portion that becomes the corner portion 24 after bending) between the core back portion 23 and the first extending portions 21a and 22a of the claw-shaped magnetic poles 21 and 22. A notch 25 is formed extending to the center. The notch 25 includes first claw-shaped magnetic poles 21 (first extending portions 21a) adjacent in the circumferential direction and second claw-shaped magnetic poles 22 (first extending portions 22a) adjacent in the circumferential direction. It is formed so as to be divided.

  Next, an annularization step for annularizing the blanking material 31 is performed. In this step, the punching material 31 is formed into an annular shape, and the first end portion 31a and the second end portion 31b in the longitudinal direction (left and right direction in FIG. 3) of the punching material 31 are fixed by welding or the like (see also FIG. 2). ). In addition, the coil part 15 is arrange | positioned on the inner peripheral side of the core back part 23 in the middle of this annularization process.

  Next, a bending process for bending the first and second claw-shaped magnetic poles 21 and 22 is performed. In this step, the boundary portions B1 between the core back portion 23 and the first extending portions 21a and 22a of the claw-shaped magnetic poles 21 and 22 are bent at right angles in the same direction to form the first extending portions 21a and 22a. To do. At this time, since the notch 25 is formed in the boundary portion B1, the first extending portions 21a and 22a can be easily bent even in a state in which the punched material 31 is circularized. Further, in each claw-shaped magnetic pole 21, 21, the boundary portion B2 between the first extending portion 21a, 22a and the second extending portion 21b, 22b is bent at a right angle in a direction facing each other, and the second extending portion 21b. , 22b. Thus, the claw-shaped magnetic poles 21 and 22 having the first extending portions 21a and 22a and the second extending portions 21b and 22b are bent. Thereby, the stator 13a of this embodiment is completed. Then, the stators 13a for three phases (three) are stacked in the axial direction while shifting the phase by 60 degrees in electrical angle. At this time, it is preferable to laminate so that the connection portions (connection portions of the first and second end portions 31a and 31b) of the blank material 31 in the stator 13a of each phase are positioned at equal intervals in the circumferential direction (120 degrees). Thereby, the magnetic imbalance which may arise by the connection part of the punching raw material 31 is suppressed, and it can contribute to the improvement of motor quality.

  According to such a manufacturing method, the stamping material 31 punched from the electromagnetic steel sheet 30 is formed into an annular shape and the stator core 14 is formed. Therefore, compared with the case where the stator core is punched into an annular shape, the waste of the electromagnetic steel sheet 30 is reduced and the yield is increased. Be improved.

Next, characteristic effects of the present embodiment will be described.
(1) The stator core 14 is formed by annularly forming a punching material 31 in which the first and second claw-shaped magnetic poles 21 and 22 are integrally formed, and both ends of the punching material 31 (first and second end portions 31a and 31b). ) Connected to each other. As a result, it is not necessary to make the punching die of the punching material 31 constituting the stator core 14 into an annular shape, so that waste of the electromagnetic steel sheet 30 can be reduced, and as a result, the yield can be improved.

  (2) The stator core 14 has a core back portion 23 that forms the outer periphery thereof, and the first and second claw-shaped magnetic poles 21 and 22 each have a first extension extending from the core back portion 23 toward the inner peripheral side. The protruding portions 21a and 22a and the second extending portions 21b and 22b extending in the axial direction from the inner peripheral ends of the first extending portions 21a and 22a are bent. According to this configuration, the first and second claw-shaped magnetic poles 21 and 22 can be suitably integrally formed with the stator core 14. Moreover, it becomes possible to earn an opposing area with the rotor 12a by the 2nd extension part 21b, 22b of each claw-shaped magnetic poles 21 and 22. FIG.

  (3) Since the notch 25 is formed at the corner 24 formed by the core back 23 and the first extending portions 21a and 22a, the core back 23 constituting the outer periphery of the stator core 14 is The first extending portions 21a and 22a can be easily bent.

In addition, you may change the said embodiment as follows.
The configuration of the stator core 14 (punching material 31) (shape, number of claw-shaped magnetic poles 21, 22 and the like) is not limited to the above embodiment, and may be changed as appropriate according to the configuration.

  For example, in the above embodiment, the notch portion 25 is formed at the boundary portion B1 (the portion that becomes the corner portion 24 after bending) between the core back portion 23 and the first extending portions 21a and 22a of the claw-shaped magnetic poles 21 and 22. In addition to this, for example, as shown in FIGS. 4 and 5, a hole 41 may be formed instead of the notch 25 of the above embodiment. In such a configuration, the first claw-shaped magnetic poles 21 (first extending portions 21a) adjacent in the circumferential direction and the second claw-shaped magnetic poles 22 (first extending portions 22a) adjacent in the circumferential direction are the above. It is comprised so that it may connect with the connection part 42, without dividing | segmenting like embodiment. Further, the hole 41 extends from the center of the first extending portion 21a of the first claw-shaped magnetic pole 21 (first extending portion 22a of the second claw-shaped magnetic pole 22) to the second claw-shaped magnetic pole 22 (first claw-shaped magnetic pole 21). ) And the core back portion 23. That is, since the end portion of the hole 41 overlaps the boundary portion B1, the first extending portions 21a and 22a can be easily bent. Even with such a configuration, it is possible to reduce the waste of the electromagnetic steel sheet 30 as in the above embodiment, and as a result, it is possible to improve the yield.

  In addition, for example, as shown in FIGS. 6 and 7, in the corner portion 43 formed by the first extension portions 21 a and 22 a and the second extension portions 21 b and 22 b in the first and second claw-shaped magnetic poles 21 and 22, A slit 44 (notch) extending in the axial direction may be formed. According to such a structure, it becomes easy to form the inner peripheral surface (surface facing the rotor 12a) of the second extending portions 21b and 22b in an arc shape, and the inner peripheral surfaces of the second extending portions 21b and 22b are formed. By making it circular arc shape, the air gap between the outer peripheral surface of the rotor 12a can be comprised uniformly, and as a result, it can contribute to the improvement of motor quality. In the example shown in FIGS. 6 and 7, the slit 44 extends to the tips of the second extending portions 21 b and 22 b, but the present invention is not limited to this, and a configuration in which holes are formed at least at the corner portions 43. It is good.

-The connection configuration of the both end portions of the punching material 31 (configuration of the first and second end portions 31a and 31b) is not limited to the above-described embodiment, and may be appropriately changed according to the configuration.
-In the manufacturing process of the stator core 14, the order of an annularization process, a bending process, and arrangement | positioning of the coil part 15 is not limited to the said embodiment, You may replace the order of those processes.

  In the above-described embodiment, the rotor 12 is embodied as the inner rotor type brushless motor M in which the rotor 12 is disposed on the inner peripheral side of the stator 13, but is not particularly limited thereto, and the outer rotor in which the rotor is disposed on the outer peripheral side of the stator. It may be embodied in a type of motor.

  M ... brushless motor, 13 (13a) ... stator, 14 ... stator core, 15 ... coil part, 21 ... first claw-shaped magnetic pole, 21a, 22a ... first extension part, 21b, 22b ... second extension part, 22 ... 2nd claw-shaped magnetic pole, 23 ... Core back part, 24, 43 ... Corner part, 25 ... Notch part, 31 ... Stamping material, 31a ... First end part, 31b ... Second end part, 41 ... Hole, 44 …slit.

Claims (6)

An annular stator core in which first claw-shaped magnetic poles and second claw-shaped magnetic poles are alternately provided at equal intervals in the circumferential direction; and a coil portion disposed between the axial directions of the first and second claw-shaped magnetic poles,
The first and second claw-shaped magnetic poles function as different magnetic poles based on energization to the coil portion,
The stator core is formed by annularly forming a punching material formed by integrally forming the first and second claw-shaped magnetic poles, and connecting both ends of the punching material. The stator according to claim 1,
The stator core has a core back portion constituting the outer periphery thereof,
Each of the first and second claw-shaped magnetic poles extends in the axial direction from a first extending portion extending from the core back portion to the inner peripheral side and from an inner peripheral end portion of the first extending portion. A stator formed by bending a second extending portion. The stator according to claim 2, wherein
A stator having a hole or a notch formed in a corner formed by the core back portion and the first extending portion. The stator according to claim 2 or 3,
A stator having a hole or a notch formed in a corner formed by the first extending portion and the second extending portion.   A motor comprising the stator according to claim 1. An annular stator core in which first claw-shaped magnetic poles and second claw-shaped magnetic poles are alternately provided at equal intervals in the circumferential direction; and a coil portion disposed between the axial directions of the first and second claw-shaped magnetic poles,
A stator manufacturing method in which the first and second claw-shaped magnetic poles function as different magnetic poles based on energization of the coil portion,
A punching process of punching a punching material integrally having the first and second claw-shaped magnetic poles from a steel plate;
After the punching step, an annularization step of forming the punching material into an annular shape and connecting both ends of the punching material,
And a bending step of bending the first and second claw-shaped magnetic poles integrally formed with the punching material.