Apparatus for manufacturing stator, method for manufacturing stator, and stator

Abstract

The present disclosure provides an apparatus for manufacturing a stator that comprises a stator core made by stacking a plurality of core pieces made of electrical steel sheets, and a coil inserted into a slot of the stator core, the apparatus comprising: a pair of coil holding jigs that hold coil ends of the coil disposed in the slot, the coil ends projecting from both ends of the stator core in the axial direction; and an activation mechanism that rotates at least one of the pair of coil holding jigs holding the coil ends, in a circumferential direction of the stator to form a skew in the stator.

Description

Stator manufacturing device, stator manufacturing method, and stator

[0001] The present disclosure relates to a stator manufacturing apparatus, a stator manufacturing method, and a stator.

[0002] In rotating electrical machines, such as induction motors, skew has traditionally been formed in rotors and stators to suppress noise and vibration caused by cogging torque, torque ripple, etc. One known method for forming skew in a stator is to insert a linear coil into a slot in a stator core that has been skewed (inclined) in advance, thereby deforming and tilting the coil along the shape of the slot.

[0003] Furthermore, WO 2019 / 142663 describes another method of forming a skew in a stator, in which a stator core is formed by stacking multiple electromagnetic steel plates, coils are placed in slots in this stator core, and a skew-forming mechanism provided on the outer or inner surface of the stator core is pressed with a skew-forming jig.

[0004] The above-mentioned method of forming a skew by inserting a straight coil into a slot of a pre-skewed stator core generates a large frictional force between the coil and the slot when the coil is inserted, which may damage the insulating coating on the surface of the coil.

[0005] Furthermore, in a method such as that described in International Publication No. 2019 / 142663, in which a stator core is pressurized after a coil is inserted into a slot to form a skew, a skew-forming mechanism (e.g., a groove or protrusion) must be provided on the outer or inner surface of the stator core, resulting in a complex shape of the stator core. Furthermore, the coil ends of the coils inserted into the slots are tilted according to the skew angle, but this tilt can vary, which can cause adjacent coil ends to interfere with each other and damage the insulating coating on the coil surface. In particular, when using flat wire coils as the coils, it is difficult to uniformly insulate the coil surface after forming the skew, so it is necessary to suppress a decrease in insulation resistance due to damage to the insulating coating, etc.

[0006] In view of the above-mentioned problems, the present disclosure aims to provide a stator manufacturing apparatus, a stator manufacturing method, and a stator that are capable of forming skew in a stator while suppressing a decrease in the insulation resistance of the coil.

[0007] In order to achieve the above object, a stator manufacturing apparatus according to a first aspect of the present disclosure is an apparatus for manufacturing a stator including a stator core formed by stacking multiple core pieces made of electromagnetic steel sheets, and coils inserted into slots of the stator core, and further including a pair of coil holding jigs that hold coil ends of the coils arranged in the slots that protrude from both axial ends of the stator core, and an operating mechanism that rotates at least one of the pair of coil holding jigs holding the coil ends in a circumferential direction of the stator in order to form a skew in the stator.

[0008] In the stator manufacturing device described above, the coil holding jig holding the coil ends is rotated, and the core pieces are rotated to follow the rotation of the coils, thereby forming a skew in the stator. Because the core pieces are simply stacked and not fixed to each other, no significant frictional force is generated between the coils and the core pieces. Furthermore, because the coil ends are skewed while held by the coil holding jig, there is no variation in the inclination of the coil ends, and interference between the coil ends can be prevented. Therefore, damage to the insulating coating of the coils can be suppressed.

[0009] A stator manufacturing apparatus according to a second aspect of the present disclosure is the stator manufacturing apparatus according to the first aspect of the present disclosure, wherein the operating mechanism rotates both of the pair of coil holding jigs holding the coil ends in the circumferential direction of the stator, and further includes a rotation control member that supports a predetermined number of the plurality of core pieces arranged in the axial middle portion of the stator core so that they cannot rotate.

[0010] In the stator manufacturing apparatus described above, by restricting the rotation of a predetermined number of core pieces arranged in the axial middle portion of the stator core using a rotation restricting member, it is possible to easily form an approximately V-shaped skew in the stator when viewed from the radial direction.

[0011] A stator manufacturing apparatus according to a third aspect of the present disclosure is the stator manufacturing apparatus according to the first aspect of the present disclosure, wherein the stator core comprises an annular yoke and a plurality of teeth provided on the inner surface of the yoke, the slots are provided between adjacent teeth and can be inserted into a central hole of the stator core formed along the axial direction of the stator core, and the apparatus further includes a core piece alignment jig that supports the plurality of core pieces so that the slots of the stator core extend along the axial direction of the stator core.

[0012] In the stator manufacturing apparatus described above, multiple core pieces can be aligned so that the slots of the stator core are straight along the axial direction, allowing coils to be inserted smoothly into the slots.

[0013] A stator manufacturing apparatus according to a fourth aspect of the present disclosure is a stator manufacturing apparatus according to the third aspect of the present disclosure, wherein the core piece alignment jig includes a cylindrical core piece alignment jig body and a guide protrusion provided on the outer surface of the core piece alignment jig body that engages with the inner ends of the teeth, and the guide protrusion can be accommodated inside the core piece alignment jig body.

[0014] In the stator manufacturing apparatus as described above, the guide protrusions can be accommodated, so that the guide protrusions do not get in the way when forming a skew in the stator.

[0015] A stator manufacturing apparatus according to a fifth aspect of the present disclosure is a stator manufacturing apparatus according to the fourth aspect of the present disclosure, wherein the operating mechanism rotates both of the pair of coil holding jigs holding the coil ends in the circumferential direction of the stator, and includes a rotation control member at the longitudinal middle portion of the core piece alignment jig body that supports a predetermined number of the plurality of core pieces that are arranged in the axial middle portion of the stator core so that they cannot rotate.

[0016] In the stator manufacturing device described above, by using a rotation restricting member to restrict the rotation of a predetermined number of core pieces arranged in the axial middle of the stator core, it is possible to easily form a substantially V-shaped skew in the stator as viewed from the radial direction. In addition, by providing the rotation restricting member on the core piece alignment jig, it is possible to simultaneously align the core pieces and restrict the rotation of some of the core pieces.

[0017] A stator manufacturing apparatus according to a sixth aspect of the present disclosure is a stator manufacturing apparatus according to any one of the first to fifth aspects of the present disclosure, wherein at least one of the pair of coil holding jigs includes a coil holding jig main body arranged at an axial end of the stator core, and a plurality of holding claws that are provided on the coil holding jig main body so as to be freely movable in the radial direction of the stator core, and that are inserted into gaps between the coil ends inserted into adjacent slots to hold the coil ends.

[0018] In the stator manufacturing device described above, the coil holding jig can hold the coil ends on a slot-by-slot basis, so that variation in the position of the coil ends is less likely to occur even after the coil holding jig is rotated, and interference between the coil ends can be suppressed.

[0019] A stator manufacturing apparatus according to a seventh aspect of the present disclosure is a stator manufacturing apparatus according to any one of the first to fifth aspects of the present disclosure, wherein the stator core includes an insulating member arranged between the slot and the coil inserted into the slot, and an insulating member support piece provided at at least one end of the stator core to support the insulating member, the insulating member support piece including an annular base, a plurality of support claws provided on the inner surface of the base, arranged between the insulating members inserted into adjacent slots, and supporting the ends of the insulating members extending outside the slots, and a support piece holding portion provided on the base, and at least one of the pair of coil holding jigs includes an engaging member that engages with the support piece holding portion of the insulating member support piece.

[0020] In the stator manufacturing apparatus described above, the insulating member support pieces that support the insulating members are rotated using a coil gripping jig, thereby making it possible to grip and rotate the coil ends on a slot-by-slot basis.

[0021] A method for manufacturing a stator according to an eighth aspect of the present disclosure includes the steps of forming a laminate by stacking a plurality of core pieces made of electromagnetic steel sheets, inserting a coil into a slot of the laminate, gripping the coil ends of the coil inserted into the slot, which protrude from both axial ends of the laminate, with a coil gripping jig, and rotating the coil gripping jig to form a skew in the laminate and the coil.

[0022] In the above-described stator manufacturing method, the coil holding jig holding the coil ends is rotated, and the core pieces are rotated to follow the rotation of the coils, thereby forming a skew in the stator. Because the core pieces are simply stacked and not fixed to each other, no significant frictional force is generated between the coils and the core pieces. Furthermore, because the coil ends are skewed while held by the coil holding jig, there is no variation in the inclination of the coil ends, and interference between the coil ends can be prevented. Therefore, damage to the insulating coating of the coils can be suppressed.

[0023] A method for manufacturing a stator according to a ninth aspect of the present disclosure is the method for manufacturing a stator according to the eighth aspect of the present disclosure, further comprising the step of supporting a predetermined number of the core pieces, among the plurality of core pieces, that are arranged in the axial middle portion of the laminate so that they cannot rotate, using a rotation restriction member.

[0024] In the above-described method of manufacturing a stator, by restricting the rotation of a predetermined number of core pieces arranged in the axial middle portion of the stator core, it is possible to easily form an approximately V-shaped skew in the stator when viewed radially.

[0025] A stator according to a tenth aspect of the present disclosure includes a stator core formed by stacking a plurality of core pieces made of electromagnetic steel sheets, and a flat wire coil inserted into a slot of the stator core, wherein the slot of the stator core is formed substantially in a V-shape, with an axial middle portion of the stator core extending along the axial direction of the stator core, and portions adjacent to both axial ends of the axial middle portion extending at an angle intersecting the axial direction, and the core pieces constituting the axial middle portion are at least three or more.

[0026] In the stator described above, a rectangular wire coil is used, which has a higher space factor than a round wire coil and can be expected to enable miniaturization and high power, and a stator having an approximately V-shaped skew when viewed from the radial direction, which can be expected to reduce cogging torque, torque ripple, and the axial magnetic attraction force applied to the rotor. Also, by providing a portion in the axial middle where the slots extend along the axial direction and using three or more core pieces to make up this portion, an approximately V-shaped skew can be formed based on this portion.

[0027] A stator according to an eleventh aspect of the present disclosure is the stator according to the tenth aspect of the present disclosure, further including an insulating member disposed between the slot and the flat wire coil inserted into the slot, and an insulating member support piece provided at at least one end of the stator core to support the insulating member, wherein the insulating member support piece includes an annular base, a plurality of support claws provided on the inner peripheral surface of the base, disposed between the insulating members inserted into adjacent slots, and supporting the ends of the insulating members extending outside the slots, and a support piece holding portion provided on the base.

[0028] In the stator described above, by providing the support piece holding portion on the insulating member support piece, it is possible to form a substantially V-shaped skew in the stator by holding and rotating this insulating member support piece.

[0029] A stator according to a twelfth aspect of the present disclosure is the stator according to the eleventh aspect of the present disclosure, wherein the support piece holding portion includes a plurality of recesses or protrusions provided on the outer peripheral surface of the base portion.

[0030] In the stator described above, the support piece holding portion can be easily formed.

[0031] The stator manufacturing apparatus, stator manufacturing method, and stator disclosed herein can provide a stator manufacturing apparatus, stator manufacturing method, and stator that can form skew in the stator while suppressing a decrease in the insulation resistance of the coil.

[0032] 5A is a schematic cross-sectional view showing an example of a stator according to the first embodiment of the present disclosure. FIG. 5B is a cross-sectional view of the stator shown in FIG. 1. FIG. 5C is a cross-sectional view taken along line A-A in FIG. 2. FIG. 5D is an enlarged arrow view of part C in FIG. 3A. FIG. 5E is an enlarged arrow view of part B in FIG. 2. FIG. 5F is a cross-sectional view of a main portion of another example of a stator according to the first embodiment of the present disclosure, the cross-sectional view corresponding to FIG. 3A. FIG. 5G is an enlarged arrow view of part D in FIG. 5A. FIG. 5H is a schematic cross-sectional view showing an example of a manufacturing apparatus for a stator according to the first embodiment of the present disclosure. FIG. 6 is a plan view showing an example of a coil gripping jig of the stator manufacturing apparatus shown in FIG. 6, illustrating a state in which the gripping claws are in a non-gripping position. FIG. 6I is a plan view showing an example of a coil gripping jig of the stator manufacturing apparatus shown in FIG. 6, illustrating a state in which the gripping claws are in a gripping position. FIG. 6I is a cross-sectional view taken along line E-E in FIG. 6. FIG. 6J is a front view showing an example of a core piece alignment jig of the stator manufacturing apparatus shown in FIG. 6. FIG. 6F is a cross-sectional view taken along line F-F in FIG. 6. FIG. 10A is an enlarged arrow view of part H in FIG. 10A. FIG. 10B is a cross-sectional view taken along line G-G in FIG. 11A. FIG. 11A is an enlarged arrow view of part J in FIG. Fig. 16 is a flowchart showing an example of a manufacturing method of a stator according to a first embodiment of the present disclosure. Fig. 17 is a plan view showing another example of the coil holding jig shown in Fig. 7. Fig. 18 is a schematic cross-sectional view showing an example of a manufacturing apparatus for a stator according to a second embodiment of the present disclosure. Fig. 19 is a perspective view showing an example of a stator manufactured using the stator manufacturing apparatus shown in Fig. 14. Fig. 20 is a cross-sectional view of the stator shown in Fig. 15.

[0033] This application is based on Japanese Patent Application No. 2022-027045, filed on February 24, 2022, the contents of which are incorporated herein by reference. The present disclosure will become more fully understood from the following detailed description. Further scope of application of the present application will become apparent from the following detailed description. However, the detailed description and specific examples are preferred embodiments of the present disclosure and are described for illustrative purposes only. From this detailed description, various changes and modifications will be apparent to those skilled in the art within the spirit and scope of the present disclosure. The applicant does not intend to dedicate any of the described embodiments to the public, and the disclosed modifications and alternatives, even if not literally included within the scope of the claims, are considered part of the invention under the doctrine of equivalents.

[0034] Hereinafter, each embodiment for carrying out the present disclosure will be described with reference to the drawings. Note that the scope necessary for the explanation to achieve the object of the present disclosure will be schematically shown below, and the scope necessary for explaining the relevant parts of the present disclosure will be mainly explained, and the parts for which explanation is omitted will be referred to as publicly known techniques. Furthermore, identical or similar reference numerals will be used to designate identical or corresponding components in the drawings, and redundant explanations will be omitted.

[0035] First Embodiment First, the structure of a stator according to a first embodiment of the present disclosure will be described. FIG. 1 is a perspective view showing an example of a stator according to the first embodiment of the present disclosure. FIG. 2 is a cross-sectional view of the stator shown in FIG. 1 cut along its longitudinal direction. As shown in FIGS. 1 and 2 , the stator 1 according to this embodiment includes at least a stator core 2 and a rectangular wire coil 3 inserted into slots 7 of the stator core 2. Note that, although the stator 1 according to this embodiment is shown as being part of an inner rotor type rotating electric machine, it may also be part of another configuration, for example, an outer rotor type rotating electric machine. Furthermore, the rotating electric machine including the stator 1 is not particularly limited, and may be, for example, a single-phase induction motor.

[0036] The stator core 2 can be configured as an annular, or more specifically, a substantially cylindrical, conductor having a central hole 2A formed in its center. The stator core 2 may be configured by stacking a plurality of core pieces 4 (e.g., several tens to several hundreds) made of magnetic material, specifically, electromagnetic steel sheets, along the central axis CA of the stator core 2. Hereinafter, the direction along the central axis CA may be simply referred to as the "axial direction." Note that, in FIGS. 1 and 2, the boundaries between the core pieces 4 constituting the stator core 2 are omitted for clarity.

[0037] Fig. 3 is a cross-sectional view of a main portion of the stator according to this embodiment, Fig. 3A is a cross-sectional view taken along line A-A in Fig. 2, and Fig. 3B is an enlarged view of part C in Fig. 3A. Fig. 4 is an enlarged view of part B in Fig. 2. As shown in Figs. 3 and 4, the core pieces 4 can be made of relatively thin plates, for example, about 0.2 to 0.5 mm thick. The core pieces 4 can be manufactured by a well-known forming method, for example, by punching out a strip of electromagnetic steel sheet as a raw material into a predetermined shape using a punch and die.

[0038] The core pieces 4 and the stator core 2 formed by stacking these core pieces 4 may include an annular yoke 5 and a plurality of teeth 6 provided on the inner peripheral surface of the yoke 5. The teeth 6 are formed so that a plurality of them extend axially at a predetermined interval from the inner peripheral surface of the yoke 5, and the space defined by adjacent teeth 6 and the inner peripheral surface of the yoke 5 may function as slots 7 into which the rectangular wire coils 3 are inserted. Furthermore, as shown in FIG. 3B , a narrow gap 7A may be formed between the inner ends 6A of adjacent teeth 6 that are close to the central axis CA. Note that in this embodiment, the yoke 5 does not have any protrusions or recesses on its outer peripheral surface. However, the present disclosure is not limited thereto. For example, the outer peripheral surface of the yoke 5 may have ears for fixing the stator 1 to the housing of a rotating electric machine (not shown), or recesses or protrusions for use in welding the core pieces 4 together.

[0039] The flat wire coil 3 can be composed of multiple segment coils formed by bending a flat conductor with a substantially rectangular cross section into a predetermined shape. The surface of the flat wire coil 3 is preferably covered with an insulating coating such as enamel. In this embodiment, a hairpin coil is used as the flat wire coil 3.

[0040] In addition, as shown in Fig. 1, when the flat wire coil 3 is inserted into the slot 7 of the stator core 2, both ends along the axial direction are inserted so as to protrude from the end of the stator core 2. Hereinafter, of the both ends of the flat wire coil 3 that protrude from the end of the stator core 2, the side that includes the curved part that is bent into a roughly U-shape will be called the first coil end 3A, the side that does not include this curved part and will be twisted and welded later will be called the second coil end 3B, and the part that is inserted into the slot 7 will be called the slot insertion part 3C. In addition, the dimensions of the flat wire coil 3, the slot 7 that is inserted, and the number of flat wire coils 3 that can be inserted into one slot 7 are not limited to those illustrated in Fig. 1, and can be variously changed.

[0041] Furthermore, the stator 1 according to this embodiment may include insulating paper 8 between the stator core 2 and the rectangular wire coil 3, specifically between the slots 7 of the stator core 2 and the slot insertion portions 3C of the rectangular wire coil 3, as an example of an insulating material for insulating the two. Well-known materials and shapes can be used for the insulating paper 8. Instead of the insulating paper 8, other insulating materials such as insulators and varnish can also be used.

[0042] The stator 1 having the above-described configuration is skewed to reduce cogging torque and torque ripple. Specifically, as shown in particular in FIGS. 2 and 4 , the slots 7 of the stator core 2 have a shape in which an axially intermediate portion X of the stator core 2 extends along the axial direction, and portions adjacent to both axial ends of the axially intermediate portion X extend at an angle intersecting the axial direction. As a result, when viewed radially, the slots 7 are substantially V-shaped with the axially intermediate portion X as the bottom. More specifically, the portion adjacent to one axial end (e.g., the upper end in FIG. 2 ) of the axially intermediate portion X extends at an angle in one direction (e.g., the left side in FIG. 2 ) toward one axial end (e.g., the upper side in FIG. 2 ) of the stator core 2, and the portion adjacent to the other axial end (e.g., the lower end in FIG. 2 ) of the axially intermediate portion X extends at an angle in one direction similar to the above-described portion toward the other axial end (e.g., the lower side in FIG. 2 ) of the stator core 2.

[0043] In this way, by forming a skew such that the slots 7 of the stator core 2 extend in a substantially V-shape when viewed radially, cogging torque and torque ripple can be reduced. It is particularly important to note that the slots 7 of the stator 1 according to this embodiment extend along the axial direction at the axially intermediate portion X. By providing a portion where the slots 7 extend along the axial direction at the axially intermediate portion X, the skew can be formed based on the axially intermediate portion X when manufacturing the stator 1 using, for example, a stator manufacturing apparatus 20 and a manufacturing method according to this embodiment, which will be described later. This improves workability during stator manufacturing. A specific method for forming the skew will be described later.

[0044] Here, the number of core laminations 4 constituting the axially intermediate portion X (hereinafter, to distinguish them from the other core laminations 4, these core laminations are also referred to as "intermediate core laminations 4X") is at least three or more. This is because, as described above, the electromagnetic steel sheets constituting the core laminations 4 are relatively thin. Therefore, if the number of intermediate core laminations 4X is small, specifically, two or less, there is a possibility that the intermediate core laminations 4X may be partially deformed when forming a skew in the stator 1. Note that the number of intermediate core laminations 4X can be changed to any number as long as it is three or more. In particular, when the total number of core laminations 4 constituting one stator core 2 is large (e.g., several hundred) or when the core laminations 4 are relatively thin (e.g., approximately 0.2 mm), it is advisable to increase the number of intermediate core laminations 4X proportionally. Note that FIG. 4 illustrates an example in which there are five intermediate core laminations 4X. By providing five or more intermediate core laminations 4X, the deformation of the core laminations 4X can be more reliably suppressed.

[0045] On the other hand, if the number of core laminations 4X in the intermediate portion described above is too large, the area where skew is formed will be reduced, and it will be impossible to sufficiently reduce cogging torque and torque ripple. Therefore, it is advisable to adjust the number of core laminations 4X in the intermediate portion to 0.5% or less of the total number of core laminations 4 that constitute one stator core 2.

[0046] By providing the above-described configuration, the stator 1 according to this embodiment reduces cogging torque and torque ripple and suppresses damage to the insulating coating of the rectangular wire coil 3. Furthermore, since the slots 7 in the axially intermediate portion X extend along the axial direction, the stator 1 having a V-shaped skew can be manufactured with good workability.

[0047] Incidentally, the insulating paper 8 of the stator 1 according to this embodiment may collapse or bend into the slot 7, for example, when the rectangular wire coil 3 inserted into the slot 7 is displaced. Therefore, in addition to the above-described configuration, the stator 1 according to this embodiment may include an insulating member support piece 10 for preventing the insulating paper 8 from collapsing as described above.

[0048] FIG. 5 illustrates another example of a stator according to the first embodiment of the present disclosure. FIG. 5A is a cross-sectional view of a main portion corresponding to FIG. 3A , and FIG. 5B is an enlarged view of portion D in FIG. 5A . The insulating member support piece 10 may be a plate-shaped member provided at one end of the stator core 2. The insulating member support piece 10 may include at least an annular base 11 and a plurality of support claws 12 provided on the inner circumferential surface of the base 11, disposed between the insulating papers 8 inserted in adjacent slots 7, and supporting the ends of the insulating papers 8 extending outside the slots 7. Note that FIG. 5 illustrates an example in which the insulating member support piece 10 is disposed on the end face of the stator core 2 on the side from which the first coil end 3A protrudes, but the insulating member support piece 10 may be disposed on at least one of both ends of the stator core 2.

[0049] The base 11 of the insulating member support piece 10 may be stacked on the end of the yoke 5 of the stator core 2. Furthermore, the outer shape of the support claws 12 of the insulating member support piece 10 may be formed to match the teeth 6 of the stator core 2, as shown in FIG. 5B , and may be positioned to match the positions of the teeth 6. In other words, the support claws 12 may be positioned to circumferentially sandwich the first coil ends 3A extending from each slot 7. When the support claws 12 are positioned in this manner, the ends of the insulating paper 8 extending outside the slots 7 are surrounded by the support claws 12 and the inner surface of the base 11, preventing the ends of the insulating paper 8 from collapsing even when the rectangular wire coil 3 is deformed.

[0050] Furthermore, it is preferable that a support piece holding portion 13 be provided on the base 11 of the insulating member support piece 10, specifically on the outer periphery of the base 11. The support piece holding portion 13 may be provided to hold the insulating member support piece 10 with an arbitrary jig. Here, the arbitrary jig may be, for example, the third and fourth coil holding jigs 30A and 40A shown in FIG. 13. In addition, in this embodiment, as shown in FIG. 5, the support piece holding portion 13 is exemplified by a plurality of recesses provided at predetermined angular intervals on the outer periphery of the base 11. However, this is not limited to this as long as it can be held by a jig. More specifically, for example, protrusions may be provided instead of the recesses, or protrusions or recesses may be provided on the surface of the base 11 opposite the surface facing the yoke 5 of the stator core 2.

[0051] Because the support claws 12 of the insulating member support pieces 10 are disposed between the first coil ends 3A, the first coil ends 3A can be rotated by holding and rotating the support piece holding portions 13 of the insulating member support pieces 10 with any jig. This makes it possible to easily form a skew in the stator 1 without having to prepare a jig with gripping claws that correspond to the arrangement of the first and second coil ends 3A, 3B.

[0052] (Stator Manufacturing Apparatus) Next, a stator manufacturing apparatus 20 according to the present embodiment will be described. The stator manufacturing apparatus 20 described below can be used to manufacture a stator similar to the stator 1 according to the present embodiment described above. Therefore, the following description will be given taking as an example a case where the stator manufacturing apparatus 20 according to the present embodiment manufactures the stator 1 described above. However, the stator manufacturing apparatus 20 according to the present embodiment can also manufacture stators other than the stator 1 described above. Specifically, it is also possible to manufacture a stator including other coils, such as round wire coils, instead of the rectangular wire coil 3, as the coil.

[0053] Fig. 6 is a schematic cross-sectional view showing an example of a stator manufacturing apparatus according to the first embodiment of the present disclosure. As shown in Fig. 6, the stator manufacturing apparatus 20 according to this embodiment can manufacture a stator 1 including a stator core 2 formed by stacking a plurality of core pieces 4 and a flat wire coil 3 inserted into the slot 7 of the stator core 2. This stator manufacturing apparatus 20 includes at least first and second coil holding jigs 30, 40 that can hold the first and second coil ends 3A, 3B of the flat wire coil 3 arranged in the slot 7, and first and second operating mechanisms 50, 60 that rotate the first and second coil holding jigs 30, 40.

[0054] The first and second coil holding jigs 30, 40 are disposed at both axial ends of the stator core 2, respectively, and are jigs for holding the first and second coil ends 3A, 3B protruding from those ends. The first and second coil holding jigs 30, 40 may have the same configuration except for their arrangement and the objects to be held. Therefore, of the first and second coil holding jigs 30, 40, the configuration of the first holding jig 30 will be described below, and the corresponding reference numerals and symbols for the second coil holding jig 40 will be indicated in parentheses, and the specific description of the first coil holding jig 30 will be used.

[0055] Fig. 7 is a plan view showing an example of a coil gripping jig of the stator manufacturing apparatus shown in Fig. 6, with Fig. 7A showing a state in which the gripping claws are in a non-gripping position and Fig. 7B showing a state in which the gripping claws are in a gripping position. Fig. 8 is a cross-sectional view taken along line E-E in Fig. 6. As shown in Figs. 6 to 8, the first coil gripping jig 30 includes at least a first coil gripping jig main body 31 (a second coil gripping jig main body 41) and a plurality of first gripping claws 32 (second gripping claws 42) that are provided on the first coil gripping jig main body 31 so as to be movable along the radial direction of the stator core 2 and that can be inserted into gaps between first coil ends 3A inserted in adjacent slots 7 to grip the coil ends 3A.

[0056] The first coil holding jig body 31 may be formed of a substantially annular member. This first coil holding jig body 31 may be rotatably attached to a first base 33 (second base 43) in the circumferential direction. Furthermore, a first through hole 34 (second through hole 44) provided in the center of the first coil holding jig body 31 may have a plurality of first accommodating grooves 35 (second accommodating grooves 45) formed in the inner wall thereof, each capable of accommodating a plurality of first gripping jaws 32.

[0057] The first gripping claws 32 are at least partially housed in the first accommodating grooves 35 and can be configured as members that can move radially using a driving device (not shown). The first gripping claws 32 can be moved between a non-gripping position in which most of the first gripping claws 32, excluding their tips, are housed in the first accommodating grooves 35, as shown in Fig. 7A, and a gripping position in which most of the first gripping claws 32, including their tips, protrude into the first through-holes 44, as shown in Fig. 7B. When moved to the gripping position, the first gripping claws 32 are arranged to circumferentially grip the first coil ends 3A protruding from the stator core 2, as shown in Fig. 8.

[0058] The first and second actuation mechanisms 50, 60 may be fixed to, for example, the first and second bases 33, 43, respectively, and may be capable of rotating the first and second coil holding jig bodies 31, 41 relative to the first and second bases 33, 43. As the first and second actuation mechanisms 50, 60, for example, well-known rotation mechanisms operated by a motor or the like may be adopted.

[0059] As shown in Figure 6, in addition to the above-mentioned configuration, the stator manufacturing apparatus 20 of this embodiment can further include a core piece alignment jig 70 for aligning the multiple core pieces 4 that make up the stator core 2.

[0060] Fig. 9 is a front view showing an example of a core piece alignment jig of the stator manufacturing apparatus shown in Fig. 6. As shown in Fig. 9, the core piece alignment jig 70 can mainly include a columnar, specifically a substantially cylindrical core piece alignment jig main body 71 having an outer diameter that matches the diameter of the central hole 2A of the stator core 2, and guide protrusions 72 that are provided on the outer peripheral surface of the core piece alignment jig main body 71 and can engage with the inner end portions 6A of the teeth 6 of the stator core 2.

[0061] FIG. 10 is a cross-sectional view of a main portion of the laminate shown in FIG. 6 , where FIG. 10A is a cross-sectional view taken along line F-F in FIG. 6 , and FIG. 10B is an enlarged view of portion H in FIG. 10A . As shown in FIGS. 9 and 10 , the guide protrusions 72 can be formed of elongated block members extending in the axial direction and can be disposed at one or more locations, for example, two locations, on the outer peripheral surface of the core piece alignment jig main body 71. Furthermore, the core piece alignment jig main body 71 may be provided with an accommodating recess 73 capable of accommodating the guide protrusions 72 at a position corresponding to the radial base of the guide protrusions 72. By providing this accommodating recess 73, the guide protrusions 72 can be accommodated in the accommodating recess 73 to temporarily release support for the core pieces 4, for example, when forming a skew in the stator 1. The movement of the guide protrusions 72 may be controlled using an actuator (not shown), or an elastic body may be provided in the accommodating recess 73 so that the guide protrusions 72 are automatically accommodated in the accommodating recess 73 when pressed against the teeth 6 or the like.

[0062] The core piece alignment jig 70 having the above-described configuration is inserted into the central hole 2A of the stator core 2, which is made up of a plurality of core pieces 4 that have been stacked in advance, or the plurality of core pieces 4 that make up the stator core 2 may be inserted sequentially from one end side of the core piece alignment jig 70. In this way, the stack of the plurality of core pieces 4 is aligned and supported with its slots 7 extending in the axial direction.

[0063] In addition to the above-described configuration, the stator manufacturing apparatus 20 according to this embodiment may further include a rotation restricting member 74 that non-rotatably supports a predetermined number (e.g., three or more) of the stacked core pieces 4 (i.e., the intermediate core pieces 4X) that are arranged in the axially intermediate portion X of the stator core 2. The specific support structure of the rotation restricting member 74 is not particularly limited as long as it is capable of non-rotatably supporting the intermediate core pieces 4X. Therefore, for example, it may be a structure that supports the outer peripheral surfaces of the intermediate core pieces 4X. In this embodiment, as shown in FIG. 8, the rotation restricting member 74 is arranged on the outer peripheral surface of a core piece alignment jig 70.

[0064] FIG. 11 is a cross-sectional view of a main portion of the laminate shown in FIG. 6 , with FIG. 11A being a cross-sectional view taken along line G-G in FIG. 6 , and FIG. 11B being an enlarged view of portion J in FIG. 11A . As shown in FIGS. 9 and 11 , the rotation restricting member 74 can be composed of multiple protrusions arranged radially at predetermined intervals in the circumferential direction on the longitudinal (i.e., axial) middle portion of the outer peripheral surface of the core piece alignment jig main body 71. The circumferential length of the rotation restricting member 74 is preferably adjusted to be equal to or slightly smaller than the gap 7A formed between the teeth 6 of the stator core 2, and the rotation restricting member 74 is positioned to engage with the gap 7A when the core piece alignment jig main body 71 is inserted into the central hole 2A of the stator core 2. The axial length of the rotation restricting member 74 is preferably set to a length sufficient to support the teeth 6 of at least three core pieces 4, e.g., 0.9 mm or more. In this embodiment, the protrusions serving as the rotation restricting members 74 are illustrated as being provided to engage with all of the gaps 7A arranged circumferentially around the stator core 2, but they may also be provided to engage with some of the gaps 7A. Furthermore, the rotation restricting members 74 may be made radially movable by adopting a structure similar to that of the above-described guide protrusions 72 so as not to affect the operation of the core piece alignment jig main body 71. In this case, the radial movement of the rotation restricting members 74 may be performed independently of the guide protrusions 72.

[0065] 11 , the rotation restricting member 74 having the above-described configuration is disposed in the gaps 7A between the intermediate core pieces 4X and can support the core pieces 4X so that they cannot rotate, by inserting the core piece aligning jig main body 71 into the central hole 2A of the stator core 2. As a result, by simply rotating the first and second coil holding jigs 30, 40 in the same direction (e.g., counterclockwise), it becomes possible to easily form a substantially V-shaped skew in the slots 7 of the stator core 2, with the slots 7 formed by the intermediate core pieces 4X supported by the rotation restricting member 74 as the bottom. Note that, in this embodiment, the core piece aligning jig 70 includes the guide protrusions 72 and the rotation restricting member 74, but instead, only the rotation restricting member 74 may be provided on the core piece aligning jig main body 71.

[0066] (Method for Manufacturing Stator) Next, a method for manufacturing a stator according to the first embodiment of the present disclosure will be described. In this embodiment, the above-described stator manufacturing apparatus 20 is employed as an apparatus for performing the stator manufacturing method, and a method for manufacturing a stator having a substantially V-shaped skew as viewed from the radial direction, such as the above-described stator 1, will be described as an example. However, it should be clearly understood that the manufacturing method of the present disclosure is not limited to implementation by the above-described manufacturing apparatus 20, and that stators having a structure different from the above-described stator 1 can also be manufactured. Note that the following description of the effects and the like also serves as a description of the effects of the stator manufacturing apparatus 20 and the stator 1 according to this embodiment.

[0067] 12 is a flowchart showing an example of a method for manufacturing a stator according to the first embodiment of the present disclosure. In the method for manufacturing a stator according to the present embodiment, first, a core piece alignment jig 70 having guide protrusions 72 and rotation restricting members 74 as shown in FIG. 8 is prepared (step S1).

[0068] Next, the core pieces 4 are sequentially supplied to one end of the core piece alignment jig 70, thereby stacking the core pieces 4 (step S2). The core pieces 4 supplied to one end of the core piece alignment jig 70 are inserted in a predetermined orientation, and then stacked in a state in which the gaps 7A of the core pieces 4 engage with the guide protrusions 72, fixing their circumferential positions. As a result, the slots 7 of the laminated body S (corresponding to the stator core 2 before skew formation) made up of multiple core pieces 4 extend straight in the axial direction. It should be noted here that the core pieces 4 do not have a structure, such as a crimped portion, that secures adjacent core pieces 4 to each other; the laminated body S is simply stacked. By performing step S7 (described later) in this state in which the core pieces 4 are not secured to each other, the core pieces 4 can be smoothly rotated, as described later.

[0069] As the supply of core pieces 4 to the core piece alignment jig 70 progresses and a core piece that constitutes the axial middle portion X of the stator core 2 (i.e., middle portion core piece 4X) is supplied, this middle portion core piece 4X moves to a position where the gap 7A formed between its teeth 6 meshes with the rotation restricting member 74, and then it is stacked on top of the adjacent other core pieces 4 and stops. As a result, the middle portion core piece 4X is supported by the rotation restricting member 74 so that it cannot rotate.

[0070] After the desired number of core pieces 4 are supplied to the core piece alignment jig 70 and the laminate S of the core pieces 4 is formed, the flat wire coil 3 is inserted into the slot 7 extending in the axial direction of the laminate S (step S3). At this time, the flat wire coil 3 inserted into the slot 7 extends straight like the slot 7, except for the end bent into an approximately U-shape. Therefore, no large frictional force is generated when inserting the flat wire coil 3 into the slot 7.

[0071] After the rectangular wire coils 3 are inserted into the slots 7 of the laminate S, the first and second coil holding jigs 30, 40 are then disposed at both ends of the laminate S (step S4). The second coil holding jig 40 may be disposed in advance at the other end of the core piece alignment jig 70 when the core piece alignment jig 70 is prepared.

[0072] Once the first and second coil holding jigs 30, 40 are positioned at both ends of the laminate S, the first and second holding claws 32, 42 are then operated to move from the non-holding position shown in FIG. 7A to the holding position shown in FIG. 7B, and the first and second holding claws 32, 42 hold the first and second coil ends 3A, 3B (step S5).

[0073] Then, the first and second operating mechanisms 50 and 60 are operated to rotate the first and second coil holding jig bodies 31 and 41 in the same direction, for example, counterclockwise. The rotation angle (skew angle) can be adjusted appropriately depending on the size of the stator to be manufactured, but for example, in the case of a two-pole machine, it can be set to 5 to 30°. As the first and second coil holding jig bodies 31 and 41 rotate, the flat wire coil 3 deforms into a roughly V-shape when viewed from the radial direction, based on the portion of the middle core piece 4X supported in the slot 7 by the rotation restriction member 74. Then, the core pieces 4, excluding the middle core piece 4X, also rotate to follow the deformation of the flat wire coil 3, forming a skew in the laminate S and the flat wire coil 3 (step S6). To ensure smooth rotation of the core piece 4, it is recommended that the guide protrusions 72 be accommodated in the accommodation recesses 73 in advance.

[0074] As described above, according to the stator manufacturing apparatus 20 and stator manufacturing method of this embodiment, the first and second coil ends 3A, 3B are gripped and rotated using the first and second coil gripping jigs 30, 40 to form a skew in the stator. Therefore, the stator manufacturing apparatus 20 and stator manufacturing method of this embodiment can reduce the frictional force generated between the rectangular wire coil 3 and the core pieces 4 compared to inserting a straight coil into a stator core with a skew. Furthermore, because the first and second gripping claws 32, 42 are disposed between adjacent slots 7, the first and second coil ends 3A, 3B are gripped and rotated by the first and second gripping claws 32, 42 for each inserted slot 7. This reduces variation in the spacing between the first and second coil ends 3A, 3B, and allows skew without interference between the first and second coil ends 3A, 3B inserted into adjacent slots 7. Furthermore, damage to the insulating coating of the rectangular wire coil 3 can be suppressed.

[0075] Furthermore, by using the rotation restricting member 74 to support only the core pieces at any position, i.e., the intermediate core pieces 4X, in a non-rotatable manner, it is possible to easily form a substantially V-shaped skew when viewed from the radial direction. In the above-described stator manufacturing method, the rotation restricting member 74 is provided on the core piece alignment jig 70 including the guide protrusions 72. Therefore, when the core pieces are stacked in step S2, the intermediate core pieces 4X are simultaneously supported in a non-rotatable manner. However, the stacking of the core pieces and the support of the intermediate core pieces 4X may be performed at different times. However, the step of supporting the intermediate core pieces 4X in a non-rotatable manner should be performed at the latest before the step of forming the skew shown in step S6.

[0076] Furthermore, since the core pieces 4 are stacked using a core piece alignment jig 70 including guide protrusions 72, it is possible to easily form a laminate S in which the slots 7 extend straight along the axial direction of the stator core 2 without fixing the core pieces 4 to each other.

[0077] The first and second coil holding jigs 30, 40 described above grip the first and second coil ends 3A, 3B using the first and second gripping jaws 32, 42, but the coil holding jigs of the present disclosure are not limited to the above-described structures. For example, if the stator to be manufactured employs an insulating member support piece 10 as shown in FIG. 5 , a coil holding jig with a structure different from the first and second coil holding jigs 30, 40 described above can be used. Therefore, as a modification of the above embodiment, a case in which third and fourth coil holding jigs 30A, 40A different from the first and second coil holding jigs 30, 40 described above are used to hold the first and second coil ends 3A, 3B will be briefly described below. The third and fourth coil holding jigs 30A, 40A described below may have the same configuration as the first and second coil holding jigs 30, 40, except for their arrangement and the objects to be held. Therefore, the following describes the configuration of the third coil holding jig 30A, out of the third and fourth coil holding jigs 30A and 40A. For the fourth coil holding jig 40A, the corresponding symbols etc. are shown in parentheses, and the specific description will be the same as that of the third coil holding jig 30A.

[0078] FIG. 13 is a plan view showing another example of the coil holding jig shown in FIG. 7 . As shown in FIG. 13 , the third coil holding jig 30A may include a third coil holding jig main body 31A (fourth coil holding jig main body 41A) rotatably attached to a third base 33A (fourth base 43A). The third coil holding jig main body 31A may be formed of a substantially annular member. A third through hole 34A (fourth through hole 44A) is provided in the center of the first coil holding jig main body 31A, and an engaging protrusion 36 (engaging protrusion 46) may be provided on the inner wall thereof to engage with the support piece holding portion 13 of the insulating member support piece 10 and rotate the insulating member support piece 10 together with the third coil holding jig main body 31A. Note that the engaging protrusions 36, 46 correspond to engaging members that engage with the support piece holding portion.

[0079] By providing the third and fourth coil holding jigs 30A, 40A with the above-described configuration, the flat wire coil 3 can be rotated with a relatively simple structure. Furthermore, if the shape of the support piece holding portion 13 of the insulating member support piece 10 is standardized, it is possible to standardize the coil holding jigs used for stator cores 2 having different numbers of slots, for example. Note that the above-described first and second coil holding jigs 30, 40 and the third and fourth coil holding jigs 30A, 40A can also be combined and used according to the structure of the stator.

[0080] Furthermore, when manufacturing a stator using the third and fourth coil holding jigs 30A and 40A, the support claws 12 of the insulating member support pieces 10 are disposed between the coil ends 3A when the rectangular wire coil 3 is inserted into the slot 7 in the above-mentioned step S2, so the above-mentioned step S5 is unnecessary. Therefore, the stator can be manufactured with fewer steps. Furthermore, when manufacturing a stator using the third and fourth coil holding jigs 30A and 40A, the order of the above-mentioned steps S3 and S4 may be changed.

[0081] Second Embodiment In the stator manufacturing apparatus 20 and stator manufacturing method according to the first embodiment described above, a case has been described in which a core piece 4X in the middle of the stator core 2 is supported so as to be non-rotatable using a rotation restricting member 74, thereby forming a skew that is approximately V-shaped when viewed from the radial direction. However, in the present disclosure, the shape of the skew of the manufactured stator is not limited to an approximately V-shape. Therefore, below, a case will be described as a stator manufacturing apparatus and a stator manufacturing method according to a second embodiment of the present disclosure, in which a skew is formed so that the slots of the manufactured stator extend in one direction inclined with respect to the axial direction of the stator.

[0082] 14 is a schematic cross-sectional view showing an example of a stator manufacturing apparatus according to the second embodiment of the present disclosure. The stator manufacturing apparatus 120 according to this embodiment may have a configuration similar to that of the stator manufacturing apparatus 20 according to the first embodiment, except that it does not have the rotation restricting member 74 and the second actuation mechanism 60. Therefore, the parts of the stator manufacturing apparatus 120 that have the same configuration as the stator manufacturing apparatus 20 are denoted by the same reference numerals, and their description will be omitted.

[0083] As described above, the stator manufacturing apparatus 120 according to this embodiment does not include the rotation restricting member 74. Therefore, the core piece aligning jig 70A according to this embodiment may be configured with a core piece aligning jig main body 71 provided with only the guide protrusions 72. All of the core pieces 4 inserted into this core piece aligning jig 70A are stacked in a rotatable state.

[0084] Furthermore, the stator manufacturing apparatus 120 does not need to include the second operating mechanism 60. As a result, the second coil holding jig 40 holds the second coil end 3B while being fixed to the second base 43. Note that the stator manufacturing apparatus 120 according to this embodiment may include the second operating mechanism 60. In that case, however, the first coil holding jig 30 rotated by the first operating mechanism 50 and the second coil holding jig 40 rotated by the second operating mechanism 60 are rotated in opposite directions.

[0085] When manufacturing a stator using the stator manufacturing apparatus 120 according to this embodiment, steps similar to those shown in FIG. 12 may be performed. Specifically, first, a core piece alignment jig 70A having guide protrusions 72 but no rotation restricting member 74 is prepared (step S1). Next, core pieces 4 are stacked by sequentially supplying them to one end of the core piece alignment jig 70A (step S2). At this time, the slots 7 of the laminate S, which is made up of multiple core pieces 4, extend straight in the axial direction. Furthermore, the core pieces 4 do not have a structure, such as a crimped portion, that fastens adjacent core pieces 4 together, and the laminate S is simply stacked.

[0086] After the desired number of core pieces 4 are supplied to the core piece alignment jig 70A and the laminate S of the core pieces 4 is formed, the flat wire coils 3 are inserted into the slots 7 extending in the axial direction of the laminate S (step S3). Then, first and second coil holding jigs 30, 40 are disposed at both ends of the laminate S (step S4), and the first and second holding jaws 32, 42 are operated to move them to their holding positions, where the first and second holding jaws 32, 42 hold the first and second coil ends 3A, 3B (step S5).

[0087] Then, the first operating mechanism 50 is operated to rotate the first coil holding jig body 31 in one direction, for example, counterclockwise. The rotation angle (skew angle) at this time can be 5 to 30°, for example, in the case of a two-pole machine. Since the second coil holding jig body 41 is fixed to the second base 43, the flat wire coil 3 is deformed linearly in a direction inclined relative to the axial direction as viewed from the radial direction, based on the second coil end 3B, by the rotation of the first coil holding jig body 31. Then, the core piece 4 also rotates to follow the deformation of the flat wire coil 3, forming a skew in the laminate S and the flat wire coil 3 (step S6).

[0088] FIG. 15 is a perspective view showing an example of a stator manufactured using the stator manufacturing apparatus shown in FIG. 14. FIG. 16 is a cross-sectional view of the stator shown in FIG. 15. The stator 1A manufactured through the above-described series of processes, as shown in FIGS. 15 and 16, differs from the stator 1 described above in the shapes of the teeth 6, slots 7, and slot insertion portions 3C of the rectangular wire coil 3. Specifically, as can be seen from the extension direction of the inner ends 6B of the teeth 6 and the gaps 7B of the slots 7 shown in FIG. 16, a linear skew is formed in a direction inclined relative to the axial direction when viewed from the radial direction. This allows for a simple method to provide a stator with reduced cogging torque and torque ripple compared to a stator without skew, without reducing the insulation resistance of the rectangular wire coil 3. Therefore, the stator manufacturing apparatus 120 and stator manufacturing method according to this embodiment can achieve the same effects as those described in the first embodiment.

[0089] The present disclosure is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present disclosure. All of these modifications are included in the technical concept of the present disclosure. Furthermore, in the present disclosure, each component may be present in only one form or in two or more forms, provided that no contradiction occurs.

[0090] All references, including publications, patent applications, and patents, cited in this specification are herein incorporated by reference to the same extent as if each reference was individually and specifically indicated to be incorporated by reference and set forth in its entirety herein.

[0091] The use of nouns and similar referents in connection with the description of this disclosure (particularly in connection with the claims that follow) shall be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The words "comprises," "has," "includes," and "comprises" shall be construed as open-ended terms (i.e., meaning "including, but not limited to"), unless otherwise noted. The recitation of numerical ranges herein is merely intended to serve as a shorthand method for referring individually to each value falling within the range, unless otherwise indicated herein, and each value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or clearly contradicted by context. Any example or exemplary language used herein (e.g., "such as"), unless otherwise claimed, is intended merely to better illustrate the disclosure and does not pose a limitation on the scope of the disclosure. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the present disclosure.

[0092] Preferred embodiments of the disclosure are described herein, including the best mode known to the inventors for carrying out the disclosure. Variations of these preferred embodiments will become apparent to those skilled in the art upon reading the foregoing description. The inventor expects that skilled persons will apply such variations as appropriate, and intends to practice the disclosure otherwise than as specifically described herein. Accordingly, this disclosure includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, this disclosure includes any combination of the above-described elements in all variations thereof unless otherwise indicated herein or otherwise clearly contradicted by context.

Claims

1. A manufacturing apparatus for a stator including a stator core formed by laminating a plurality of core pieces made of electromagnetic steel sheets and a coil inserted into a slot of the stator core, a pair of coil holding jigs for holding coil ends of the coils disposed in the slots, the coil ends protruding from both ends of the stator core in the axial direction; an operating mechanism for rotating at least one of the pair of coil holding jigs holding the coil ends in a circumferential direction of the stator in order to form a skew in the stator; Stator manufacturing equipment.

2. the actuation mechanism rotates both of the pair of coil holding jigs holding the coil ends in a circumferential direction of the stator, The stator core further includes a rotation restricting member that supports a predetermined number of the core pieces arranged in an axial middle portion of the stator core so as not to rotate. The apparatus for manufacturing a stator according to claim 1 .

3. The stator core includes an annular yoke and a plurality of teeth provided on an inner peripheral surface of the yoke, the slots being provided between adjacent teeth, a core piece alignment jig that can be inserted into a central hole of the stator core formed along the axial direction of the stator core and supports the plurality of core pieces so that the slots of the stator core extend along the axial direction of the stator core; The apparatus for manufacturing a stator according to claim 1 .

4. the core piece alignment jig includes a columnar core piece alignment jig body and a guide protrusion that is provided on an outer peripheral surface of the core piece alignment jig body and engages with an inner end portion of the tooth, The guide protrusion can be accommodated inside the core piece alignment jig body. The apparatus for manufacturing a stator according to claim 3 .

5. the actuation mechanism rotates both of the pair of coil holding jigs holding the coil ends in a circumferential direction of the stator, a rotation restricting member provided in a longitudinal intermediate portion of the core piece aligning jig body for non-rotatably supporting a predetermined number of the core pieces, which are arranged in an axial intermediate portion of the stator core, among the plurality of core pieces; The apparatus for manufacturing a stator according to claim 4 .

6. At least one of the pair of coil holding jigs includes a coil holding jig body disposed at an axial end of the stator core, and a plurality of holding claws provided on the coil holding jig body so as to be movable in a radial direction of the stator core, the holding claws being inserted into gaps between the coil ends inserted into adjacent slots to hold the coil ends. The apparatus for manufacturing a stator according to any one of claims 1 to 5.

7. the stator core includes an insulating member disposed between the slot and the coil inserted into the slot, and an insulating member support piece provided at at least one end of the stator core and supporting the insulating member, the insulating member support piece includes an annular base, a plurality of support claws provided on an inner circumferential surface of the base, the support claws being disposed between the insulating members inserted into adjacent slots and supporting ends of the insulating members extending outside the slots, and a support piece holding portion provided on the base, At least one of the pair of coil holding jigs includes an engaging member that engages with the support piece holding portion of the insulating member support piece. The apparatus for manufacturing a stator according to claim 1 .

8. A step of forming a laminate by stacking a plurality of core pieces made of electromagnetic steel sheets; inserting a coil into a slot of the laminate; gripping, with a coil gripping jig, coil ends of the coils inserted into the slots, the coils protruding from both axial ends of the laminate; and rotating the coil holding jig to form a skew in the laminate and the coil. A method for manufacturing a stator.

9. The method further includes a step of supporting a predetermined number of core pieces arranged in an axial middle portion of the laminated body, among the plurality of core pieces, so as to be non-rotatable by using a rotation restricting member. The method for manufacturing a stator according to claim 8 .

10. a stator core formed by laminating a plurality of core pieces made of electromagnetic steel sheets; A rectangular wire coil is inserted into the slot of the stator core; An insulating member disposed between the slot and the rectangular wire coil inserted into the slot; an insulating member support piece provided at at least one end of the stator core to support the insulating member, The slots of the stator core are formed substantially in a V-shape, with an axial intermediate portion of the stator core extending along the axial direction of the stator core, and portions adjacent to both axial ends of the axial intermediate portion extending at an angle in a direction intersecting the axial direction, The number of the core pieces constituting the axially intermediate portion is at least three, The insulating member support piece includes an annular base, a plurality of support claws provided on an inner circumferential surface of the base, disposed between the insulating members inserted into the adjacent slots, and supporting ends of the insulating members extending outside the slots, and a support piece holding portion provided on the base. Stator.

11. The support piece holding portion includes a plurality of recesses or protrusions provided on the outer peripheral surface of the base portion, The stator of claim 10.