JP2008131679A - Stator manufacturing method and stator - Google Patents

Abstract

A stator manufacturing method and a stator capable of reducing the cogging torque by improving the roundness of the inner periphery of the core of the rotating electrical machine having a split core structure without adding a manufacturing process. To do.
Each split core is annularly shaped so that a tip end surface of each tooth that faces a rotor follows a molding surface by setting a gap between circumferential end portions of split yokes in adjacent split cores. Then, the divided cores 12 are integrated to form a stator core. For this reason, the gap set between the split cores 12 can absorb the dimensional error of the split cores 12 and maintain the roundness of the inner circumference of the stator core following the shape of the molding surface.
[Selection] Figure 3

Description

  The present invention relates to a stator manufacturing method and a stator having a structure (divided core structure) in which a plurality of divided cores in a rotating electric machine are annularly arranged.

  Conventionally, in this type of stator, a core is formed by integrating a plurality of split cores in an annular shape, and an increase in the inner diameter step of the core due to a dimensional error of the split core (decrease in the roundness of the core inner periphery facing the rotor) ), And variations in magnetic distortion generated at the contact points between adjacent divided cores. And in the rotary electric machine provided with such a stator, the magnetic balance is lost due to these, and so-called cogging torque is generated, and accordingly, there are various problems such as vibration and noise. Therefore, as a technique for solving this problem, for example, there is one disclosed in Patent Document 1.

In Patent Document 1, variation in the magnetic resistance value of adjacent divided cores is suppressed from a cylindrical iron sleeve provided so as to be in close contact with the outer peripheral surface of the annularly arranged divided cores, thereby reducing the cogging torque. Yes.
JP 2003-284269 A

  By the way, in the stator as described above, the cogging torque and the roundness of the inner circumference of the core have a strong correlation. For this reason, after core integration, cogging torque can be reduced by applying sizing or Superoll processing to the inner periphery of the core to increase the roundness of the inner periphery of the core. This increases the manufacturing cost.

  The present invention has been made in order to solve the above-mentioned problems, and the object thereof is to increase the roundness of the inner circumference of the core of a rotating electrical machine having a split core structure without adding a manufacturing process. It is an object of the present invention to provide a stator manufacturing method and a stator that can be improved to reduce cogging torque.

  In order to solve the above-mentioned problem, the invention according to claim 1 is characterized in that a split core having an arc-shaped split yoke and teeth extending from the inner peripheral side of the split yoke is provided after the windings are mounted on the teeth. A method of manufacturing a stator in which a plurality of divided yokes are arranged in an annular shape and integrated with each other, and a tip surface of each of the teeth facing a rotor is formed as a molding surface by setting a gap between adjacent divided cores. The gist of the invention is to arrange the divided cores in a ring shape so as to conform to the above, and then integrate the divided cores.

  In the present invention, a gap is set between adjacent divided cores, and the divided cores are arranged in an annular shape so that the tip surfaces of the teeth facing the rotor follow the molding surface, and then the divided cores are integrated. . For this reason, the gap set between the split cores can absorb the dimensional error of the split cores and maintain the roundness of the inner circumference of the core following the shape of the molding surface. Therefore, it is possible to improve the roundness of the inner circumference of the core and reduce the cogging torque without adding a manufacturing process.

  According to a second aspect of the present invention, in the stator manufacturing method of the first aspect, the stator is press-fixed to an inner periphery of a case, and the gap between the divided cores is determined by the stator. The gist of the present invention is to set the dimensions so as to remain even in a state in which the inner periphery of the case is pressed and fixed.

In the present invention, the gap set between the split cores can be left even in a state where the stator is pressed and fixed to the inner periphery of the case.
According to a third aspect of the present invention, in the stator manufacturing method according to the first or second aspect, a metal core having a circumferential outer peripheral surface as the molding surface is used, and a tip surface of each of the teeth is the molding surface. The gist of this is that the respective divided cores are arranged in a ring shape by being brought into pressure contact with a pressure device.

  In the present invention, using a core bar having a circumferential outer peripheral surface as a molding surface, the tip surfaces of the teeth are pressed against the molding surface by a pressurizing device, and the divided cores are arranged in an annular shape. . As a result, the inner circumference of the core is formed following the outer diameter of the core bar, and the horizontal processing distortion of the core is suppressed, so that the roundness of the inner circumference of the core can be improved more reliably and easily. . Moreover, it can respond only by setting the diameter of a core metal large, and can easily form a gap between the divided cores.

  According to a fourth aspect of the present invention, in the stator manufacturing method according to the third aspect, each of the divided cores is positioned in the circumferential direction by being engaged with an engaging portion provided in the pressure device. This is the gist.

  In this invention, the split core is positioned in the circumferential direction by engaging with the engaging portion of the pressurizing device when the core is formed. For this reason, a substantially uniform gap can be formed at all locations between adjacent divided cores, thereby suppressing variations in magnetic distortion between the divided yokes and improving the roundness of the inner circumference of the core. In addition, the cogging torque can be further reduced.

  According to a fifth aspect of the present invention, in the stator manufacturing method according to any one of the third or fourth aspects, the divided cores are engaged with engaging portions provided on the cored bar. The gist is to be positioned in the circumferential direction.

  In this invention, the split core is positioned in the circumferential direction by engaging with the engaging portion of the cored bar when forming the core. For this reason, a substantially uniform gap can be formed at all locations between adjacent divided cores, thereby suppressing variations in magnetic distortion between the divided yokes and improving the roundness of the inner circumference of the core. In addition, the cogging torque can be further reduced.

  A sixth aspect of the present invention is the stator manufacturing method according to any one of the first to fifth aspects, wherein the divided core is formed by stacking a plurality of laminated members in the axial direction and adjacent to each other. The gist is that the laminated members of the divided cores are brought into contact with each other in the axial direction in the axial direction.

  In the present invention, the laminated members of adjacent divided cores are provided so as to contact in the axial direction. As a result, the portion where the laminated member abuts in the axial direction becomes a magnetic flux passage path, so that the influence on the motor characteristics predicted by the reduction of the horizontal magnetic flux due to the gap between the adjacent divided cores is suppressed. Can do.

  According to a seventh aspect of the present invention, there is provided a split core having a split yoke and a tooth extending at a substantially right angle from an inner peripheral side of the split yoke. Is a method of manufacturing a stator that is integrated in an annular state and is integrated in that state, with a gap provided so that a circumferential contact force does not act between the adjacent divided cores. The gist is to arrange the cores in an annular shape and then integrate the divided cores with the gaps.

  In the present invention, since the divided cores are integrated by setting a gap between the adjacent divided cores, it is possible to obtain a stator that does not generate a contact force in the circumferential direction of the divided cores. As a result, when the stator is press-fixed to the inner peripheral surface of the case at its outer peripheral surface, the gap set between the split cores is reduced, but an excessive contact force acts on the peripheral direction of the split core. As a result, it is possible to suppress the deterioration of the roundness of the core inner circumference formed by the inner circumference side tip of the teeth. Therefore, it is possible to improve the roundness of the inner circumference of the core and reduce the cogging torque without adding a manufacturing process.

  According to an eighth aspect of the present invention, there is provided a split core having a split yoke and a tooth extending substantially at right angles from an inner peripheral side of the split yoke, and the split core having the tooth tip as an inner side after the winding is mounted on the tooth. Is a method of manufacturing a stator, in which the stator is pressed between the adjacent divided cores, and the stator is pressed against the inner periphery of the case in the circumferential direction. The gist of the invention is to arrange the divided cores in a ring shape with a gap such that the contact force does not act, and then integrate the divided cores with the gap provided.

  According to the present invention, it is possible to obtain a stator in which a contact force is not generated in the circumferential direction of the split core even when the stator is press-fixed to the inner peripheral surface of the case. For this reason, the roundness of the inner periphery of the core formed by the tip on the inner periphery side of the teeth can be maintained in a state before being pressed and fixed to the case. In addition, when a split core is integrated by placing a cored bar on the inner periphery of the core, a highly accurate perfect circle cannot be obtained by springback after the cored bar is removed from the core. This is possible.

  According to a ninth aspect of the present invention, there is provided a split core having a split yoke and a tooth with a winding extending substantially perpendicularly from an inner peripheral side of the split yoke, and the split core is annularly formed with the tooth tip as an inner side. A stator that is integrated and arranged in an arrayed state and is press-fixed to the inner periphery of the case, and between the adjacent divided cores, the stator is also connected to the inner periphery of the case. The gist is that there remains a gap where a contact force in the direction does not act.

  In the present invention, even when the stator is pressed against and fixed to the inner peripheral surface of the case by the gap formed between the split cores, no contact force is generated in the circumferential direction of the split core. The roundness of the circumference can be suitably maintained, and thereby the cogging torque can be reduced.

  The invention according to claim 10 is the stator according to claim 9, wherein the divided core is formed by laminating a plurality of laminated members in the axial direction, and the laminated members of the adjacent divided cores are The gist is that they overlap in the axial direction at the circumferential end.

  In this invention, since the part which overlaps with an axial direction becomes a passage path of magnetic flux, in the magnetic flux which passes between division | segmentation cores, the magnetic flux part of the horizontal direction reduced with a gap | interval can be compensated.

  Therefore, the roundness of the inner circumference of the core can be improved and the cogging torque can be reduced without increasing the number of parts in the stator of the rotating electrical machine having the split core structure or adding a manufacturing process.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of the invention will be described with reference to the drawings.
FIG. 1 shows a brushless motor 1 of the present embodiment. As shown in FIG. 1, a substantially cylindrical stator 3 is pressed and fixed to the inner peripheral surface of a bottomed cylindrical case 2 constituting the brushless motor 1. A rotor 4 having a plurality of magnets 5 arranged in the circumferential direction so as to face the stator 3 on the outer peripheral surface is disposed inside the stator 3.

  The stator core 11 as a core constituting the stator 3 is formed by arranging twelve divided cores 12 having a substantially T-shape when viewed in the axial direction in the circumferential direction. Each of the split cores 12 has a split yoke 12a having an arc shape when viewed from the axial direction of the stator core 11 and a substantially right angle from a substantially center in the circumferential direction of the split yoke 12a when viewed from the axial direction of the stator core 11. The extending teeth 12b are integrally formed. At the tip of the tooth 12b, a protruding portion 12c that is formed to protrude on both sides in the circumferential direction is integrally provided. Each of the split cores 12 is integrated in an annular shape by performing welding on the outer peripheral surface of the facing portion 20 where the circumferential ends of the adjacent split yokes 12a face each other.

  As shown in FIGS. 2A, 2 </ b> B, and 2 </ b> C, each divided core 12 includes a first laminated member 21 that is substantially T-shaped, and a second laminated member that is symmetrical with the first laminated member 21. Two types of laminated members 22 and 22 are alternately laminated. 2A and 2B, two first laminated members 21 and two second laminated members 22 are shown for convenience of explanation.

  As shown in FIG. 2A, the plate-like first laminated member 21 includes an arc-shaped laminated divided yoke 21a that is laminated to form the divided yoke 12a, and a substantially right angle from the substantially center in the circumferential direction of the laminated divided yoke 21a. A substantially rectangular laminated tooth 21b extending so as to form a substantially triangular shaped laminated protrusion 21c protruding from the tip of the laminated tooth 21b to both sides in the circumferential direction is integrally formed. At one end in the circumferential direction of the laminated split yoke 21a (the left end in FIG. 2A) is formed a semicircular convex portion 21d that projects in a semicircular shape in the circumferential direction, and in the circumferential direction. A semicircular recess 21e formed in a substantially semicircular shape in the circumferential direction is formed at the other end (the right end in FIG. 2A). And in the adjacent 1st lamination member 21, the semicircle convex part 21d of the other 1st lamination member 21 is engage | inserted from the radial direction outer side or the circumferential direction in the semicircle recessed part 21e of one 1st lamination member 21. It is like that. In addition, the laminated split yoke 21a has a planar surface extending along the radial direction of the split yoke 12a in the radially inner portion of the portion where the semicircular convex portion 21d and the semicircular concave portion 21e are provided. 21f is formed.

  In the first laminated member 21 configured as described above, the semicircular convex portion 21d fits into the semicircular concave portion 21e of the adjacent first laminated member 21, and the first laminated portion is formed by the semicircular convex portion 21d and the semicircular concave portion 21e. The rotation of the members 21 is guided. Then, the opposing surfaces 21 f of the adjacent first laminated members 21 face each other at the end position of the rotation of the split core 12. Further, a gap G is formed between the adjacent semicircular convex portions 21d and semicircular concave portions 21e and between the opposing surfaces 21f (see FIG. 2C).

  As shown in FIG. 2B, the second laminated member 22 is axisymmetric with the first laminated member 21. The plate-like second laminated member 22 includes an arc-shaped laminated divided yoke 22a that is laminated to form the divided yoke 12a, and a substantially rectangular laminated member that extends at a substantially right angle from the circumferential center of the laminated divided yoke 22a. The teeth 22b and the substantially triangular laminated protrusions 22c protruding from the tip of the laminated teeth 22b to both sides in the circumferential direction are integrally formed.

  The other end in the circumferential direction of the laminated split yoke 22a (the right end in FIG. 2B) is formed with a semicircular convex portion 22d that protrudes in a semicircular shape in the circumferential direction. A semicircular recess 22e formed in a substantially semicircular shape in the circumferential direction is formed at one end in the direction (the left end in FIG. 2B). In the adjacent second laminated member 22, the semicircular convex portion 22d of the other second laminated member 22 is fitted into the semicircular concave portion 22e of one second laminated member 22 from the radially outer side or the circumferential direction. It is like that. In addition, the laminated split yoke 22a has a planar shape extending along the radial direction of the split yoke 12a in the radially inner portion of the portion where the semicircular convex portion 22d and the semicircular concave portion 22e are provided. 22f is formed.

  In the second laminated member 22 configured as described above, the semicircular convex portion 22d fits into the semicircular concave portion 22e between the adjacent second laminated members 22, and the second is formed by the semicircular convex portion 22d and the semicircular concave portion 22e. The rotation of the laminated members 22 is guided. The opposing surfaces 22f of the adjacent second laminated members 22 face each other at the end position of the rotation of the split core 12. Further, a gap G is formed between the adjacent semicircular convex portions 22d and semicircular concave portions 22e and between the opposing surfaces 22f (see FIG. 2C). In the present embodiment, the gap G is set so that the interval is 1 to 20 μm in the circumferential direction even after the stator 3 is pressed and fixed to the case 2.

  These divided cores 12 shown in FIG. 1 are formed by alternately laminating the first laminated member 21 and the second laminated member 22 two by two in the thickness direction. The divided yoke 12a is formed by the laminated laminated yokes 21a and 22a, the teeth 12b are formed by the laminated first and laminated teeth 21b and 22b, and the laminated protrusions 21c and 22c are laminated. Thus, the protruding portion 12c is formed. The two circumferential ends of the divided yoke 12a have a comb-teeth shape by alternately laminating the first laminated member 21 and the second laminated member 22 that are line symmetrical with each other (FIG. 2 ( c)). Note that the tip surface 12d of the tooth 12b including the protruding portion 12c forms an arc shape and faces the rotor 4 when viewed from the stacking direction of the first and second stacked members 21 and 22. An outer peripheral recess 12e extending in the axial direction is formed at the center in the longitudinal direction on the outer peripheral surface of each divided yoke 12a.

  In the stator core 11, a cylindrical yoke 11a is formed by divided yokes 12a arranged in the circumferential direction. As shown in FIG. 2C, the divided yoke 12a adjacent to each other in the yoke 11a forms the gap G between the first and second laminated members 21 and 22 adjacent to each other in the circumferential direction. 12a is engaged with the facing portion 20 at the circumferential end. Further, a wrap portion 23 is formed in the facing portion 20 so that the first and second laminated members 21 and 22 of the adjacent split core 12 overlap in the plate thickness direction.

  The divided cores 12 are arranged in the circumferential direction so that the tips of the teeth 12b are directed radially inward and the teeth 12b are radial. Twelve slots 13 are formed by the teeth 12b adjacent in the circumferential direction, and a gap is provided between the protrusions 12c adjacent in the circumferential direction. The stator core 11 includes an insulator 14 that covers a portion other than the outer peripheral surface and the inner peripheral surface of the stator core 11 and that can be connected and rotated between adjacent ones (not shown), in the axial direction of the stator core 11. It is mounted from both sides. A winding 15 is wound around each tooth 12b so as to pass through the slot 13 from above the insulator 14. The winding 15 is supplied with power from a power supply device (not shown).

Next, a method for manufacturing the stator 3 will be described.
First, a split core forming step for forming the split core 12 is performed. In this divided core forming step, first, the first laminated member 21 and the second laminated member 22 are formed by punching a metal plate with a press (not shown). Then, by laminating the first laminated member 21 and the second laminated member 22 alternately in the plate thickness direction and integrating them by caulking in the axial direction, both ends in the circumferential direction of the divided yoke 12a are comb-like. A split core 12 is formed.

  Next, an arrangement process for assembling the twelve divided cores 12 is performed. In this arrangement step, the twelve divided cores 12 include the first laminated member 21 in each divided core 12 and the semicircular protrusions 21 d and 22 d of the second laminated member 22 in the first laminated member 21 in the adjacent divided core 12. And fitted into the semicircular recesses 21e, 22e of the second laminated member 22, respectively. Thereafter, the insulator 14 is mounted. As a result, the twelve split cores 12 are rotatably connected, and a lap portion 23 is formed in which the first and second laminated members 21 and 22 of the adjacent split cores 12 overlap in the plate thickness direction.

  Next, a winding process is performed in which the winding 15 is wound around each of the teeth 12b from above the insulator 14. In this winding step, the twelve divided cores 12 constituting the stator core 11 are arranged so that the teeth 12b are parallel and the divided yoke 12a is substantially linear. In this state, the winding 15 is wound around each tooth 12b.

  Next, a shaping step for integrating the 12 divided cores 12 around which the windings 15 are wound in an annular shape is performed. As shown in FIGS. 3A and 3B, in the split core 12 around which the winding 15 is wound, the tip surface 12 d of the tooth 12 b comes into contact with the outer peripheral surface 31 a as the molding surface of the cylindrical cored bar 31. In this way, the metal core 31 is wound in an annular shape. In FIGS. 3A and 3B, the insulator 14 and the winding 15 are omitted for convenience of explanation. The cored bar diameter (outer diameter) D of the cored bar 31 around which each divided core 12 is wound is set to a predetermined dimension in consideration of the outer diameter of the rotor 4 and the air gap between the rotor 4. Further, the core metal diameter D is a predetermined dimension (specifically, larger than the core inner diameter (the diameter of the inner peripheral surface of the stator core 11 formed by the tip surface 12d of the teeth 12b) in which the adjacent divided yokes 12a abut against each other at the facing portion 20. (Which will be described later). For this reason, the split core 12 is wound around the core metal 31 in a state where the gap G is provided between the first and second laminated members 21 and 22 adjacent to each other in the circumferential direction in the facing portion 20.

  Further, a ring-shaped pressurizing device 32 is disposed on the radially outer side of the split core 12 wound in an annular shape. The pressurizing device 32 is divided into three at equal intervals in the circumferential direction, and three divided slits 32a extending in the axial direction are provided at equal intervals in the circumferential direction, respectively. The gaps 33 between the slits 32a and the respective pressurizing devices 32 are respectively arranged according to the facing portions 20 at both ends of each divided yoke 12a. Further, the pressurizing device 32 is formed in a tapered shape whose outer peripheral surface 32b extends downward, and is provided so as to be movable in the radial direction, and the inner peripheral surface follows the tapered shape of the pressurizing device 32. By pressing from above the cylindrical outer jig 34 formed in a tapered shape, a pressing force is applied to the radially inner side. Then, with the pressing device 32, each of the divided cores 12 arranged in an annular shape is pressed radially inward against the outer peripheral surface 31 a of the cored bar 31, and between the processing slit 32 a and each pressing device 32. The gaps 33 are integrated by welding on the outer peripheral surface of the facing portion 20 of the split yoke 12a.

  In the stator core 11 formed as described above, the difference in distance from the proximal end to the distal end surface 12d of the teeth 12b adjacent to each other (core inner diameter) in the inner periphery of the stator core 11 formed by the outer peripheral surface 31a of the cored bar 31. Step) is reduced, and accordingly, the roundness of the inner periphery of the stator core 11 is increased. Further, since the core metal diameter D is set large as described above, a gap G is formed between the first and second laminated members 21 and 22 adjacent to each other in the circumferential direction in the facing portion 20, and the gap G Thus, dimensional errors between the divided cores 12 are absorbed. After the welding process, the metal core 31 is removed from the stator core 11. However, since the gap G is formed in the facing portion 20, no stress (contact force) acting in the circumferential direction is generated between the facing portions 20, and the core inner diameter is the core. The state following the outer peripheral surface 31a of the gold 31 is maintained, and the roundness of the inner periphery of the stator core 11 is maintained even after the core 31 is removed.

  Then, the stator core 11 composed of twelve divided cores 12 is press-fitted and fixed in the case 2 by shrink fitting or the like, whereby the stator 3 is completed. When the stator core 11 is pressed against the case 2, the gap G formed in the stator core 11 is narrowed. However, even when the stator 3 is completed, the core diameter D is large so that the gap G remains. Thus, the contact force in the circumferential direction at the facing portion 20 does not act, and the size of the core inner diameter step of the stator core 11 is reduced. In the present embodiment, the diameter of the cored bar D is set so that a gap G of about 30 μm is formed in each facing portion 20 when the stator core 11 is formed. This gap G is fixed to the stator core 11 by pressure contact. Even after, about 1 to 20 μm remains. Further, as shown in FIG. 4A, the larger the core metal diameter D used to form the stator core 11, the smaller the core inner diameter step.

  In the brushless motor 1 including the stator 3 formed in this manner, the core inner diameter step of the stator core 11 is small and the roundness is improved. Therefore, since the air gap with the rotor 4 is suitable at any position in the rotational direction, the variation in magnetic distortion is reduced, and the cogging torque is reduced (see FIG. 4B). In addition, since the magnetic flux passing through the facing portion 20 detours up and down through the wrap portion 23 (white arrow in FIG. 2C), the first and second laminated members 21 adjacent in the circumferential direction by the gap G, There is no adverse effect on the motor characteristics of the brushless motor 1 that is predicted by the fact that the magnetic flux hardly passes between the two.

Next, characteristic actions and effects of the present embodiment will be described.
(1) The gaps G are set between the circumferential ends of the divided yokes 12a in the adjacent divided cores 12, and the divided cores 12 are annularly formed so that the tip surfaces 12d of the teeth 12b facing the rotor 4 follow the molding surface. Then, the divided cores 12 are integrated. For this reason, the gap G set between the split cores 12 can absorb the dimensional error of the split cores 12 and maintain the roundness of the inner periphery of the stator core 11 following the shape of the molding surface. Therefore, it is possible to improve the roundness of the inner periphery of the stator core 11 and reduce the cogging torque without adding a manufacturing process.

  (2) Since the gap G provided between the split cores 12 remains even when the stator 3 is press-fixed to the inner periphery of the case 2, the roundness of the inner periphery of the stator core 11 can be increased even after being fixed to the case 2. It can be suitably maintained.

  (3) Using the cored bar 31 having the circumferential outer peripheral surface 31 a as a molding surface, the tip surface 12 d of each tooth 12 b is pressed against the outer peripheral surface 31 a of the cored bar 31 by the pressure device 32. The divided cores 12 are arranged in a ring shape. As a result, the inner circumference of the stator core 11 is formed following the outer diameter of the cored bar 31 and processing distortion in the horizontal direction of the stator core 11 is suppressed, so that the roundness of the inner circumference of the stator core 11 can be more reliably and easily performed. Can be improved. Further, it can be dealt with by simply setting the diameter of the cored bar 31, and the gap G can be easily formed between the divided cores 12.

  (4) The split core 12 is formed with a lap portion 23 in which the first and second laminated members 21 and 22 of the split core 12 adjacent to each other overlap in the axial direction. Thereby, since the wrap part 23 becomes a magnetic flux passage path, the influence on the motor characteristics of the brushless motor 1 predicted by the reduction of the horizontal magnetic flux due to the gap G between the adjacent divided yokes 12a is suppressed. Can do.

The embodiment of the present invention may be modified as follows.
In addition to the above embodiment, as shown in FIG. 5, a fitting portion 41 as an engaging portion that extends in the axial direction is formed on the inner peripheral surface of the pressurizing device 32, and the divided core 12 is integrated in an annular shape In order to achieve this, the fitting portion 41 may be fitted into the outer peripheral recess 12e of the split core 12 to position the split core 12 in the circumferential direction. Further, as shown in FIG. 6, when the engaging convex portion 51 extending in the axial direction is formed on the outer peripheral surface 31 a of the core metal 31 and the split core 12 is integrated into an annular shape, the engaging convex portion 51 is divided. The split core 12 may be positioned in the circumferential direction by engaging between the protruding portions 12c of the core 12. According to this configuration, it is possible to form a substantially uniform gap G between any of the adjacent divided yokes 12a, thereby suppressing variations in magnetic distortion at each facing portion 20, and reducing the core inner diameter step. The cogging torque can be further reduced in conjunction with the decrease in. In addition, you may position the split core 12 by both the fitting part 41 and the engagement convex part 51. FIG.

  In the above embodiment, the split core 12 is configured by alternately laminating the first and second laminated members 21 and 22 two by two. However, the present invention is not limited to this, for example, three or more May be alternately stacked, or may be alternately stacked one by one. In addition, it is good also as a structure which does not have the lap | wrap part 23 by laminating | stacking only the 1st lamination member 21 (2nd lamination member 22). Furthermore, you may comprise the division | segmentation core 12 from one member, without making it laminated.

In the above embodiment, the adjacent divided cores 12 are integrated by welding, but may be integrated by, for example, adhesion or fastening other than welding.
In the above embodiment, the stator 3 is press-fixed to the case 2, but it may be simply fixed to the inner periphery of the case 2 instead of press-contacting.

In the above embodiment, the gap G remains even after the stator 3 is pressed and fixed to the case 2, but it is sufficient that the gap G is formed at least when the divided cores 12 are integrated.
In the above embodiment, the columnar core 31 is used, but the present invention is not limited to this. For example, a cylindrical one may be used.

  In the above embodiment, the present invention has been described by taking the stator 3 provided in the brushless motor 1 as an example. However, the present invention is not limited to this, and the present invention may be applied to a stator of a rotating electrical machine other than the brushless motor.

It is radial direction sectional drawing of the brushless motor in this Embodiment. (A) is a top view of a 1st laminated member, (b) is a top view of a 2nd laminated member, (c) is the schematic which shows typically the passage route of the magnetic flux in a stator core. (A) is radial direction sectional drawing which shows schematically the shaping process of a split core, (b) is an axial sectional view which shows schematically the shaping process of a split core. (A) is a graph which shows the relationship between the magnitude | size of a metal core diameter, and the magnitude | size of a core internal-diameter level | step difference, (b) is a graph which shows the relationship between the magnitude | size of a core internal-diameter level | step difference, and the magnitude | size of a cogging torque. It is radial direction sectional drawing which shows the fitting part of a pressurization apparatus. It is radial direction sectional drawing which shows the engagement convex part of a metal core.

Explanation of symbols

  D ... core metal diameter, G ... gap, 2 ... case, 3 ... stator, 4 ... rotor, 11a ... yoke, 12 ... split core, 12a ... split yoke, 12b ... teeth, 14d ... tip surface, 15 ... winding, DESCRIPTION OF SYMBOLS 21 ... 1st laminated member, 22 ... 2nd laminated member, 23 ... Lapping part, 31 ... Core metal, 31a ... Outer peripheral surface as a molding surface, 32 ... Pressurizing device, 41 ... Fitting part as engaging part, 51. Engaging convex portion as an engaging portion.

Claims (10)

A stator configured by dividing a plurality of divided yokes into an annular shape and integrating them with a divided core having an arc-shaped divided yoke and teeth extending from the inner peripheral side of the divided yoke. A manufacturing method of
A gap is set between the adjacent divided cores, the divided cores are arranged in an annular shape so that the front end surfaces of the teeth facing the rotor follow the molding surface, and then the divided cores are integrated. A stator manufacturing method characterized by the above. In the manufacturing method of the stator according to claim 1,
The stator is press-fixed to the inner periphery of the case,
The gap between the divided cores is set to such a size that the stator remains even in a state where the stator is pressed and fixed to the inner periphery of the case. In the manufacturing method of the stator according to claim 1 or 2,
Using a metal core having a circumferential outer peripheral surface as the molding surface, the tip surfaces of the teeth are brought into pressure contact with the molding surface by a pressure device, and the divided cores are arranged in an annular shape. A method for manufacturing a stator. In the manufacturing method of the stator according to claim 3,
Each stator core is positioned in the circumferential direction by being engaged with an engaging portion provided in the pressure device. In the manufacturing method of the stator according to claim 3 or 4,
Each of the divided cores is positioned in the circumferential direction by being engaged with an engaging portion provided on the metal core. In the stator manufacturing method according to any one of claims 1 to 5,
The split core is formed by laminating a plurality of laminated members in the axial direction,
A method for manufacturing a stator, wherein the laminated members of adjacent divided cores are overlapped in the axial direction in the axial direction. A split core having a split yoke and a tooth extending at a substantially right angle from the inner peripheral side of the split yoke is arranged in an annular shape with the tooth tip inside, after the winding is mounted on the tooth, and in this state A stator manufacturing method comprising an integrated structure,
Arranging the split cores annularly with a gap so that circumferential contact force does not act between the adjacent split cores,
Thereafter, the respective divided cores are integrated in a state where the gap is provided. A split core having a split yoke and a tooth extending at a substantially right angle from the inner peripheral side of the split yoke is arranged in an annular shape with the tooth tip inside, after the winding is mounted on the tooth, and in this state A stator manufacturing method comprising:
Between the adjacent divided cores, the divided cores are arranged in an annular shape with a gap so that a circumferential contact force does not act even in a state where the stator is pressed and fixed to the inner periphery of the case,
Thereafter, the respective divided cores are integrated in a state where the gap is provided. A split core having a split yoke and a tooth that extends substantially at right angles from the inner peripheral side of the split yoke and is provided with a winding is integrated and configured with the split cores arranged in an annular shape with the teeth tip inside. And a stator that is press-fitted and fixed to the inner periphery of the case,
The stator is characterized in that a gap remains between the adjacent divided cores so that a circumferential abutment force does not act even when the stator is pressed against and fixed to the inner periphery of the case. The stator according to claim 9, wherein
The split core is formed by laminating a plurality of laminated members in the axial direction,
The laminated members of the adjacent divided cores overlap each other in the axial direction at the circumferential end.

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