WO2021144900A1 - Stator and method for manufacturing stator - Google Patents

Abstract

Provided is a stator which facilitates downsizing and in which a plurality of coil segments can be joined favorably.　In one embodiment, a plurality of coil segments 19 provided to a stator 12 have linear sections 19a arranged side by side, within slots 20, in the radial direction of the stator core 16, and have extending end sections 19b extending to the exterior from one end surface 16a of a stator core 16. The extending end sections 19b are each folded along the circumferential direction of the stator core 16 so that a corresponding pressing surface 19c lies along the one end surface16a. A plurality of the pressing surfaces 19c are arranged side by side along the radial direction of the stator core 16. Two pressing surfaces 19c adjacent to each other in the radial direction are joined to each other, and an inclined surface 19c1 faces an extending end section 19b radially adjacent thereto on the outer circumferential side.

Description

Stator and how to manufacture the stator

An embodiment of the present invention relates to a stator and a method for manufacturing a stator.

The rotary electric machine has a tubular stator and a rotor rotatably provided with respect to the stator. The stator has a stator core formed by laminating a large number of annular electromagnetic steel sheets, and a coil attached to the stator core. A coil formed by joining a plurality of coil segments has coil ends protruding in the axial direction from both end faces of the stator core. In recent years, the stator of a rotary electric machine has been desired to be further miniaturized.

Japanese Unexamined Patent Publication No. 2006-304507 JP-A-2017-85806

An object of the embodiment of the present invention is to provide a stator and a method for manufacturing a stator capable of satisfactorily joining a plurality of coil segments while achieving miniaturization.

The stator of the embodiment includes one end surface located at one end in the axial direction and the other end surface located at the other end in the axial direction, and a plurality of slots extending in the axial direction and opening to the one end surface and the other end surface, respectively. It includes a stator core having and, and a plurality of coil segments, each of which is mounted in the slot and joined to each other to form a multi-phase coil. Each of the coil segments is formed of a flat conductor, and is provided at the other end of the straight line portion, a pair of straight line portions facing each other at intervals, a bridge portion connecting one ends of the straight line portions to each other, and the straight line portion. A pressing surface inclined with respect to the axial direction of the portion and an inclined surface formed by chamfering at least one corner of the tip of the straight portion including the pressing surface are integrally provided. A plurality of the straight portions of the plurality of coil segments are arranged side by side in the radial direction of the stator core in the slot, and have an extending end portion extending outward from the one end surface of the stator core. ing. Each of the extending ends is bent in the circumferential direction of the stator core so that the pressing surface is along the one end surface, and the plurality of pressing surfaces are arranged side by side in the radial direction of the stator core. The two pressing surfaces adjacent to each other in the radial direction are joined to each other, and the inclined surface faces the extending end portion adjacent to the outer peripheral side in the radial direction.

In the method for manufacturing a stator of the embodiment, a pair of straight portions formed of flat conductors and facing each other at intervals, a bridge portion connecting one ends of the straight portions to each other, and a bridge portion connecting one ends of the straight portions are provided at the other end of the straight portion. A plurality of coils integrally having a pressing surface inclined with respect to the axial direction of the straight portion and an inclined surface formed by chamfering at least one corner of the tip of the straight portion including the pressing surface. Prepare a segment. The straight portions of the plurality of coil segments having the inclined surface positioned radially outside the stator core are inserted into the plurality of slots from one end surface side of the stator core, and the other end surface side of the stator core. By forming a plurality of extending ends protruding in the axial direction from the above and arranging a plurality of the straight portions arranged in the radial direction in each slot, the extending ends are coaxial with the stator core. Arrange in a multi-layered cylindrical shape. While pressing the pressing surface toward the other end surface in the axial direction of the stator core by the pressing portion of the pressing jig, at least one of the stator core and the pressing jig is rotated in the circumferential direction. ..

FIG. 1 is a vertical sectional view showing a rotary electric machine according to an embodiment. FIG. 2 is a cross-sectional view showing the rotary electric machine. FIG. 3 is a perspective view showing the other end surface side of the stator of the rotary electric machine. FIG. 4 is an enlarged perspective view showing a coil end portion of the coil segment of the stator in region A of FIG. FIG. 5A is a perspective view showing the coil segment. FIG. 5B is an enlarged perspective view showing the tip of one of the pair of tip portions of the coil segment in the region B of FIG. 5A. FIG. 5C is an enlarged perspective view showing the tip of the other straight line portion in the region C of FIG. 5A among the pair of tip portions of the coil segment. FIG. 6 is a perspective view showing a stator core and coil segments arranged in a cylindrical shape. FIG. 7 is a perspective view showing a state in which the coil segment is attached to the stator core. FIG. 8 is a perspective view showing the other end surface side of the stator core and the extending end portion of the coil segment. FIG. 9 is an enlarged perspective view showing the region D of FIG. FIG. 10 is a perspective view showing a state in which the inner wall jig is attached to the inside of the stator core. FIG. 11 is a perspective view showing a molding jig for bending and molding the coil segment. In FIG. 12, 48 coil segments located in the 6th layer (outermost layer) of the coil segments mounted on the stator core are first (first time) bent by the 48 forming jigs. The perspective view which shows the state of molding. FIG. 13 is a perspective view showing a state of one coil segment in the region F of FIG. 12 before bending and forming. FIG. 14 is a perspective view showing a state after bending and molding of one coil segment in the region F of FIG. FIG. 15 is a side view schematically showing the process of bending and forming the coil segment. In FIG. 16, 48 coil segments located in the first layer (innermost layer) of the coil segments mounted on the stator core are finally (sixth) folded by the 48 molding jigs. The perspective view which shows the state of bending molding. FIG. 17 is a perspective view showing a state of one coil segment in the region G of FIG. 16 before bending and forming. FIG. 18 is a perspective view showing a state after bending and molding of one coil segment in the region G of FIG. FIG. 19 is an enlarged perspective view showing a pressing surface of the bent and molded coil segment. FIG. 20 is a perspective view showing a bending process of a coil segment using an inner wall jig and an outer wall jig. FIG. 21 is an enlarged perspective view showing a part of the extended end portion of the coil segment in the bending process. FIG. 22 is a perspective view showing a bent extended end portion in the region H of FIG. 20. FIG. 23 is an enlarged perspective view showing the pressing surface in the region J of FIG. 21. FIG. 24 is a perspective view showing a welding process of the coil segment. FIG. 25 is an enlarged perspective view showing a pressing surface of the welded coil segment in the region K of FIG. 24. FIG. 26 is an enlarged perspective view showing the tip of one straight portion of the pair of tip portions of the coil segment of the modified example.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
It should be noted that the disclosure is merely an example, and those skilled in the art can easily conceive of appropriate changes while maintaining the gist of the invention are naturally included in the scope of the present invention. Further, in order to clarify the explanation, the drawings may schematically represent the width, thickness, shape, etc. of each part as compared with the actual embodiment, but this is just an example, and the interpretation of the present invention is used. It is not limited. Further, in the present specification and each figure, the same elements as those described above with respect to the above-mentioned figures may be designated by the same reference numerals, and detailed description thereof may be omitted as appropriate.

(Embodiment)
First, an example of a rotary electric machine to which the stator according to the embodiment is applied will be described.
FIG. 1 is a vertical cross-sectional view of the rotary electric machine according to the embodiment, and shows only one half of the rotary electric machine with the central axis C1 as the center. FIG. 2 is a cross-sectional view of the rotary electric machine.

As shown in FIG. 1, the rotary electric machine 10 is configured as, for example, a permanent magnet type rotary electric machine. The rotary electric machine 10 includes an annular or cylindrical stator 12, a rotor 14 that is rotatable inside the stator 12 around the central axis C1 and is coaxially supported with the stator 12, and these stators. A casing 30 that supports the rotor 12 and the rotor 14 is provided.
In the following description, the extending direction of the central axis C1 is referred to as an axial direction, the direction of rotation around the central axis C1 is referred to as a circumferential direction, and the directions orthogonal to the axial direction and the circumferential direction are referred to as a radial direction.

As shown in FIGS. 1 and 2, the stator 12 includes a cylindrical stator core 16 and a rotor winding (coil) 18 wound around the stator core 16. The stator core 16 is formed by laminating a large number of annular electromagnetic steel plates 17 made of a magnetic material, for example, silicon steel, in a concentric manner. A large number of electrical steel sheets 17 are connected to each other in a laminated state by welding a plurality of locations on the outer peripheral surface of the stator core 16. The stator core 16 has one end surface 16a located at one end in the axial direction and the other end surface 16b located at the other end in the axial direction. The one end surface 16a and the other end surface 16b extend orthogonally to the central axis C1.

A plurality of slots 20 are formed in the inner peripheral portion of the stator core 16. The plurality of slots 20 are arranged at equal intervals in the circumferential direction. Each slot 20 opens on the inner peripheral surface of the stator core 16 and extends in the radial direction from the inner peripheral surface. Each slot 20 extends over the entire length of the stator core 16 in the axial direction. One end of each slot 20 is open to one end surface 16a, and the other end is open to the other end surface 16b. It should be noted that each slot 20 may be configured not to open on the inner peripheral surface of the stator core 16.
By forming the plurality of slots 20, the inner peripheral portion of the stator core 16 constitutes a plurality of (for example, 48 in this embodiment) teeth 21 protruding toward the central axis C1. The teeth 21 are arranged at equal intervals along the circumferential direction. As described above, the stator core 16 integrally has an annular yoke portion and a plurality of teeth 21 protruding in the radial direction from the inner peripheral surface of the yoke portion toward the central axis C1.

Coil 18 is embedded in a plurality of slots 20 and wound around each tooth 21. The coil 18 has coil ends 18a and 18b extending outward in the axial direction from one end surface 16a and the other end surface 16b of the stator core 16. By passing an alternating current through the coil 18, a predetermined interlinkage magnetic flux is formed in the stator 12 (teeth 21).

As shown in FIG. 1, iron core end plates 24 having substantially the same cross-sectional shape as the stator core 16 are provided at both ends of the stator core 16 in the axial direction. Further, an iron core retainer 26 is provided on these iron core end plates 24.
The casing 30 has a substantially cylindrical first bracket 32a and a bowl-shaped second bracket 32b. The first bracket 32a is connected to the iron core retainer 26 located on the drive end side of the stator core 16. The second bracket 32b is connected to the iron core retainer 26 located on the opposite drive end side. The first and second brackets 32a and 32b are made of, for example, an aluminum alloy. An annular bearing bracket 34 is coaxially fastened to the tip end side of the first bracket 32a with bolts. For example, a first bearing portion 36 incorporating a roller bearing 35 is fastened to the central portion of the bearing bracket 34. A second bearing portion 38 containing, for example, a ball bearing 37 is fastened to the central portion of the second bracket 32b.

On the other hand, the rotor 14 has a cylindrical shaft (rotating shaft) 42 rotatably supported by the first and second bearing portions 36 and 38 about the central axis C1 and a substantially central portion in the axial direction of the shaft 42. It has a cylindrical rotor core 44 fixed to the rotor core 44, and a plurality of permanent magnets 46 embedded in the rotor core 44. The rotor core 44 is configured as a laminated body in which a large number of magnetic materials, for example, a large number of annular electromagnetic steel plates 47 such as silicon steel are laminated concentrically. The rotor core 44 has an inner hole 48 formed coaxially with the central axis C1. The shaft 42 is inserted and fitted into the inner hole 48 and extends coaxially with the rotor core 44. A substantially disk-shaped magnetic shielding plate 54 and a rotor core retainer 56 are provided at both ends of the rotor core 44 in the axial direction.

As shown in FIGS. 1 and 2, the rotor core 44 is coaxially arranged with a slight gap (air gap) inside the stator core 16. That is, the outer peripheral surface of the rotor core 44 faces the inner peripheral surface (tip surface of the teeth 21) of the stator core 16 with a slight gap.

The rotor core 44 is formed with a plurality of magnet embedding holes penetrating in the axial direction. A permanent magnet 46 is loaded and arranged in each magnet embedding hole, and is fixed to the rotor core 44 by, for example, an adhesive or the like. Each permanent magnet 46 extends over the entire length of the rotor core 44. Further, the plurality of permanent magnets 46 are arranged at predetermined intervals in the circumferential direction of the rotor core 44.

As shown in FIG. 2, the rotor core 44 has a d-axis extending in the radial direction or the radial direction of the rotor core 44, and a q-axis electrically separated from the d-axis by 90 °. Here, the axis extending in the radial direction through the boundary between adjacent magnetic poles and the central axis C1 is defined as the q-axis, and the direction electrically perpendicular to the q-axis is defined as the d-axis. The d-axis and the q-axis are provided alternately in the circumferential direction of the rotor core 44 and in a predetermined phase.

Two permanent magnets 46 are arranged on both sides of each d-axis in the circumferential direction of the rotor core 44. Each permanent magnet 46 is formed in an elongated flat plate shape having a rectangular cross section, and has a length substantially equal to the axial length of the rotor core 44. When viewed in a cross section orthogonal to the central axis C1 of the rotor core 44, the permanent magnets 46 are each inclined with respect to the d-axis. The two permanent magnets 46 are arranged side by side in a substantially V shape, for example. Here, the ends of the permanent magnets 46 on the inner peripheral side are adjacent to the d-axis and face each other with a slight gap. The outer peripheral end of the permanent magnet 46 is separated from the d-axis along the circumferential direction of the rotor core 44, and is located near the outer peripheral surface of the rotor core 44 and near the q-axis. As a result, the outer peripheral end of the permanent magnet 46 is adjacent to the outer peripheral end of the adjacent magnetic poles of the permanent magnet 46 with the q-axis in between.

FIG. 3 is a perspective view showing the other end surface side of the stator, FIG. 4 is a perspective view showing an enlarged view of the second coil end portion of the stator in the region A of FIG. 3, and FIG. 5A shows a coil segment. The perspective view shown, FIG. 5B is an enlarged perspective view showing the tip of one straight portion in the region B of FIG. 5A among the pair of tip portions of the coil segment, and FIG. 5C is a perspective view showing the tip of the pair of tip portions of the coil segment. FIG. 5 is an enlarged perspective view showing the tip of the other straight portion in the region C of FIG. 5A. As shown in FIGS. 3 and 4, the coil 18 is configured by using a plurality of coil segments 19 made of copper flat wire having a rectangular cross section as a flat conductor, and is assembled to a stator core 16.
A flat conductor has a substantially rectangular shape in a cross section perpendicular to the longitudinal direction (cross section), or has at least two long sides facing each other in a cross section perpendicular to the longitudinal direction. When the cross section (cross section) perpendicular to the longitudinal direction of the flat conductor is rectangular, the four corners do not have to be right angles and may be chamfered or rounded. Further, when the cross section (cross section) perpendicular to the longitudinal direction has two opposite long sides, the portion connecting the ends of these two opposite long sides in the cross section may be curved, for example, in an oval shape. ..

As shown in FIG. 5A, the coil segment 19 is formed into a substantially U shape by cutting and bending a flat wire. That is, the coil segment 19 integrally has a pair of straight line portions 19a facing each other at intervals and a bridging portion 19d connecting one ends of the straight line portions 19a. The coil segment 19 has a rectangular cross-sectional shape, i.e., the cross-section has a pair of long sides facing each other and a pair of short sides facing each other. The outer surface of the coil segment 19 is covered with an insulating coating 19f (indicated by dots) such as enamel. The insulating coating 19f is removed from the extending end of each straight portion 19a so that it can be conducted. Each straight portion 19a constitutes an extending end portion 19b protruding from the stator core 16 by a predetermined length. The tip of each straight portion 19a is cut diagonally and has a pressing surface (tip surface) 19c inclined at an angle θ1 (less than 90 °) with respect to the central axis C2 of the straight portion 19a. The pressing surface 19c is formed in a rectangular shape, a pair of long sides are inclined by an angle θ1 with respect to the central axis C2, and a pair of short sides extend in a direction orthogonal to the central axis C2.

As shown in FIGS. 5A and 5B, at least one corner 19x (shown by a broken line in FIG. 5B) of the tip (including the pressing surface 19c) of one straight portion 19a, here, a stator, as will be described later. The corner portion 19x located on the outer peripheral side of the iron core 16 is chamfered or cut out to form an inclined surface 19c1 inclined at an angle θ2 (7 to 10 degrees in one example) with respect to the long side of the pressing surface 19c. There is. The length L1 of the inclined surface 19c1 on the pressing surface 19c is formed to be about 2 to 4 mm in one example.
Similarly, as shown in FIGS. 5A and 5C, at least one corner 19y (shown by a broken line in FIG. 5C) of the tip (including the pressing surface 19c) of the other straight portion 19a, as described below. The corner portion 19y located on the outer peripheral side of the stator core 16 is chamfered or cut out to form an inclined surface 19c2 inclined by a predetermined angle θ2 with respect to the long side of the pressing surface 19c. The length L2 of the inclined surface 19c2 on the pressing surface 19c is longer than L1, and is formed to be about 3 to 5 mm in one example.
The inclined surfaces 19c1 and 19c2 are provided so as to be located on the same surface side of the coil segment 19. That is, the inclined surfaces 19c1 and 19c2 are arranged so as to face the radial outer side of the stator core 16 when the coil segment 19 is mounted on the stator core 16.
The inclination angles θ2 of the inclined surfaces 19c1 and 19c2 may be common or may be different from each other. The lengths L1 and L2 are not limited to L2> L1 and may be L2 = L1.
The insulating coating 19f shown by dots in FIGS. 5A, 5B and 5C is not shown in drawings other than FIGS. 5A, 5B and 5C.

As shown in FIG. 3, the plurality of coil segments 19 are arranged in a plurality of cylinders, here in a six-layer cylindrical shape, and a pair of linear portions 19a of each coil segment are, for example, one of the stator cores 16. It is inserted into the corresponding different slots 20 from the end surface 16a side, and protrudes from the other end surface 16b of the stator core 16 by a predetermined length. As shown in FIG. 2, for example, six straight line portions 19a are inserted into one slot 20. In the slot 20, the six straight portions 19a are arranged side by side in the radial direction of the stator core 16. The six straight lines 19a are arranged in the slot 20 with their long sides facing each other in parallel.

The cross-linked portion 19d of the coil segment 19 faces the one end surface 16a of the stator core 16 with a slight gap. The cross-linking portion 19d extends along substantially the circumferential direction of the stator core 16, and some cross-linking portions 19d extend so as to intersect with other cross-linking portions 19d. These cross-linked portions 19d form a coil end 18a protruding from one end surface 16a.

As shown in FIGS. 3 and 4, the straight portion 19a extending from the other end surface 16b in the axial direction of a predetermined length is bent along the circumferential direction of the stator core 16 and is inclined with respect to the axial direction. Is postponed. Specifically, the extending end portion 19b of each straight portion 19a is inclined with respect to the axial direction from the first bending portion 19M and the first bending portion 19M which are bent at a predetermined angle from the axial direction of the stator core 16 in the circumferential direction. It has an inclined portion 19N extending linearly. The pressing surface 19c located at the tip of the extending end portion 19b is located substantially parallel to the other end surface 16b of the stator core 16.

The extending end portions 19b of the six straight portions 19a inserted into each slot 20 are alternately bent in one direction and the opposite direction. That is, the extending end portion 19b located on the innermost circumference is bent in one direction in the circumferential direction of the stator core 16, and the extending end portion 19b on the outer side is in the other direction (opposite direction) in the circumferential direction. It is bent into. Further, the extending end portion 19b on the outer side is bent in one direction. The six extending ends 19b extending from the plurality of different slots 20 are bent so that the pressing surfaces 19c are located substantially in a line in the radial direction of the stator core 16. These six pressing surfaces 19c extend substantially in the same plane.

The tip surfaces or pressing surfaces 19c of the six straight portions 19a in each row arranged in the radial direction are mechanically and electrically joined to each other by two (two each). For joining, for example, laser welding can be used. A weld bead 19g is formed by irradiating the two pressing surfaces 19c with laser light to partially melt the conductor. By joining two tip portions adjacent to each other in the radial direction, a three-phase coil 18 is formed by the entire plurality of coil segments. Further, the extending end portion 19b constitutes a coil end 18b protruding from the other end surface 16b of the stator core 16. The tip portion (conductive portion) including the pressing surface (welded surface) of the straight portion 19a is covered with an insulating material (not shown) such as powder coating or varnish.
As shown in FIG. 3, U-phase connection terminal TU, V-phase connection terminal TV, and W-phase connection terminal TW are connected to three of the coils 18, respectively.

Next, an example of a method for manufacturing a stator of a rotary electric machine according to an embodiment will be described.
FIG. 6 is a perspective view showing the stator core 16 and the coil segments 19 arranged in a cylindrical shape.
As shown in FIG. 6, first, a large number of coil segments 19 are prepared and arranged in a cylindrical shape. Although not shown, three sets of coil segments 19 arranged in a cylindrical shape are prepared. A set (48) of coil segments 19 are arranged in a cylindrical shape along a plurality of slots 20 of the stator core 16. One set of coil segments 19 includes two coil segments 19U1 and 19U2 for the U phase, two coil segments 19V1 and 19V2 for the V phase, and two coil segments 19W1 and 19W2 for the W phase, for a total of 6 The book is the minimum unit, and it is composed of 8 units. In one set arranged in a cylindrical shape, the straight portions 19a of the coil segments 19 are arranged in two rows in the radial direction. That is, a large number (48 × 2) of straight portions 19a are arranged in a cylindrical shape having two layers having different diameters.

FIG. 7 is a perspective view showing a state in which the coil segment 19 is attached to the stator core 16.
As shown in FIG. 7, each set of coil segments 19 is inserted into the slot 20 from the one end surface 16a side of the stator core 16. At this time, the coil segment 19 is arranged so that the inclined surfaces 19c1 and 19c2 face the radial outer side of the stator core 16. The straight portion 19a of the coil segment 19 is inserted into the slot 20 and protrudes from the other end surface 16b of the stator core 16 by a predetermined length to form an extending end portion 19b. The 96 (48 × 2) straight lines 19a located at both ends of a set (48) of coil segments 19 arranged in a cylindrical shape correspond to two layers of cylinders in the corresponding 48 slots 20. Then, for example, it is inserted at the positions of the 6th layer (outermost layer) and the 5th layer. Three sets (144, 48 × 3) of coil segments 19 arranged in a cylindrical shape are inserted into the corresponding 48 slots 20 from the one end surface 16a side of the stator core 16. The straight portion 19a and the extending end portion 19b of the three sets of coil segments 19 are arranged in a concentric, six-layered cylindrical shape having different diameters. In each slot 20, the straight line portions 19a are arranged side by side in the radial direction from the sixth layer (outermost layer) to the first layer (innermost layer).

FIG. 8 is a perspective view in which all the coil segments 19 are mounted on the stator core 16 and the coil segments 19 are turned upside down, and FIG. 9 is an enlarged perspective view showing the region D in FIG.
As shown in FIGS. 8 and 9, the stator core 16 to which the coil segment 19 is mounted is oriented upside down due to bending molding of the extension end portion 19b of the coil segment 19 described later. The six straight portions 19a inserted into each slot 20 are located side by side in the radial direction of the stator core 16. The inclined surfaces 19c1 and 19c2 of the coil segment 19 are located on the radial outer side of the stator core 16. Hereinafter, in the radial direction, the coil segment, the straight portion, the extending end portion, and the pressing surface located in the outermost layer (sixth layer) are set to 19P, 19Pa, 19Pb, and 19Pc, and the coil segment and the straight portion located in the fifth layer. , The extending end portion and the pressing surface are 19Q, 19Qa, 19Qb and 19Qc, and the coil segment located in the fourth layer, the straight portion, the extending end portion and the pressing surface are 19R, 19Ra, 19Rb and 19Rc, and the third layer. The coil segment, the straight portion, the extending end portion, and the pressing surface located in are 19S, 19Sa, 19Sb, 19Sc, and the straight portion, the extending end portion, and the pressing surface located in the second layer are 19T, 19Ta, 19Tb, 19Tc. The coil segment, the straight portion, the extending end portion, and the pressing surface located in the innermost layer (first layer) are referred to as 19Ua, 19Ub, and 19Uc.
The inclination directions of the pressing surfaces 19Pc, 19Qc, 19Rc, 19Sc, 19Tc, and 19Uc arranged in the radial direction are alternately reversed. That is, the pressing surfaces 19Pc, 19Rc, 19Tc of the 6th layer, the 4th layer, and the 2nd layer are inclined in the same direction, and the pressing surfaces 19Qc, 19Sc, 19Uc of the 5th layer, the 3rd layer, and the 1st layer are reversed. It is tilted in the direction.

FIG. 10 is a perspective view showing a state in which the inner wall jig 101 is attached to the inside of the stator core 16.
As shown in FIG. 10, the inner wall jig 101 is arranged inside the extending end portion 19Ub of the innermost layer arranged in a cylindrical shape. The inner wall jig 101 is formed in a cylindrical shape and has an outer peripheral surface 101a that functions as a support surface. The inner wall jig 101 is made of a metal having sufficient rigidity. The diameter of the inner wall jig 101 is formed to be substantially equal to the inner diameter of the cylinder formed by the extending end portion 19Ub of the innermost layer. The inner wall jig 101 is not limited to a cylindrical shape, and may be formed in a solid cylindrical shape.
The inner wall jig 101 is arranged coaxially with the stator core 16 and is inserted inside the extending end portion 19Ub of the innermost layer. As a result, the outer peripheral surface 101a of the inner wall jig 101 is adjacent to and opposed to the inner peripheral side surface of the extending end portion 19Ub. When the extension end 19Ub of the innermost layer is bent and formed in the circumferential direction of the stator core 16, the inner wall jig 101 prevents the extension end 19Ub from inclining inward in the radial direction of the stator core 16. , The extending end portion 19Ub is supported from the inner peripheral side. Here, the extending end portion 19Ub located in the first layer (innermost layer) does not have another extending end portion 19b adjacent to the inside in the radial direction of the stator core 16. Therefore, by supporting the extending end portion 19Ub located in the first layer (innermost layer) from the inside in the radial direction by the inner wall jig 101, it is prevented from falling toward the inside in the radial direction.

FIG. 11 is a perspective view showing a molding jig 102 for bending and molding the coil segment 19.
In FIG. 11, eight molding jigs 102 (pressing jigs) are shown as an example. As shown in FIG. 12 and the like described later, the molding jig 102 is composed of 48 pieces as a set, and is arranged in a cylindrical shape at substantially equal intervals. One set of molding jigs 102 bends and molds by simultaneously pressing 48 extending end portions 19b of each one layer of the coil segments 19 mounted on the stator core 16.

The forming jig 102 has a prismatic main body 102a extending parallel to the central axis of the stator core 16, that is, extending in the vertical direction, and a pressing portion 102b extending downward from the main body 102a and having the lower end curved in an arc shape. And a flange portion 102c located radially outside the stator core 16 with respect to the pressing portion 102b, and are integrally formed of metal or the like. The flange portion 102c is formed to have a larger width and length than the pressing portion 102b, and protrudes outward from both side edges and the lower end edge of the pressing portion 102b. That is, the flange portion 102c is formed so as to cover the pressing portion 102b from the radial outer side to the inner side of the stator core 16. Specifically, the forming jig 102 partially cuts both side edges and the lower end edge of the lower end of the main body 102a to press the portion located inside the stator core 16 in the radial direction. The portion of the stator core 16 located on the outer side in the radial direction is defined as the flange portion 102c. The main body 102a is supported by a support that can be raised and lowered (not shown).

Using the above-mentioned set of molding jigs 102, the extending end portion 19b of the coil segment 19 is bent and molded for each layer. In one example, the forming jig 102 pushes and bends the extending end portion 19b from the outermost layer (sixth layer) toward the innermost layer (first layer) for each layer.

FIG. 12 is a perspective view showing a step of bending and molding 48 extending end portions 19Pb located in the sixth layer (outermost layer) by the forming jig 102.
As shown in FIG. 12, the spacing between the pair of forming jigs 102 is adjusted so that they are arranged in a diameter substantially matching the diameter of the cylinder composed of the extending end portion 19Pb of the outermost layer. The molding jig 102 is arranged at a position where the 48 molding jigs 102 are aligned with the 48 extending end portions 19Pb, and the pressing portion 102b is brought into contact with the pressing surface (tip surface) 19Pc of the extending end portion 19Pb. , The flange portion 102c is brought into contact with the outer peripheral side surface of the extending end portion 19Pb. In this state, the forming jig 102 is lowered in the axial direction to press the extension end portion 19Pb via the pressing surface 19Pc, and the stator core 16 is tilted around the central axis in the inclination direction of the pressing surface 19Pc, here. It rotates counterclockwise CCW. As a result, the 48 extending end portions 19Pb of the outermost layer are bent, and the pressing surface 19Pc is in a state along the other end surface 16b, for example, in a state of being substantially parallel to the other end surface 16b of the stator core 16. In the present embodiment, the stator core 16 is rotated around the central axis, but the relative position of the stator core 16 of the forming jig 102 in the circumferential direction with respect to the central axis may change, and the forming jig The 102 may be rotated around the central axis of the stator core 16, or both the stator core 16 and the forming jig 102 may be rotated in the opposite directions in the circumferential direction around the central axis of the stator core 16. You can move it.

FIG. 13 is a perspective view showing the state of the coil segment 19P before bending and molding, and FIG. 14 is a perspective view showing the state of the coil segment 19P after bending and molding. FIG. 15 is a side view schematically showing the bending molding process.
As shown in FIGS. 13 and 15 (A), in the state immediately before the bending molding, the extending end portion 19Pb is upward from the other end surface 16b of the stator core 16 along the axial direction of the stator core 16. It protrudes into. The pressing surface 19Pc of the extending end portion 19Pb is inclined with respect to the central axis. The pressing portion 102b of the forming jig 102 abuts on the pressing surface 19Pc, and the flange portion 102c supports the outer surface of the extending end portion 19Pb toward the inside of the stator core 16 in the radial direction.

As shown in FIGS. 14, 15 (B), (C), and (D), the molding jig 102 is lowered, and the pressing portion 102b makes the pressing surface 19Pc the other end surface 16b along the axial direction of the stator core 16. While pressing sideways, the stator core 16 is rotated counterclockwise CCW. As a result, the extension end portion 19Pb is pushed down and bent in the direction opposite to the inclination direction of the pressing surface 19Pc and in the circumferential direction of the stator core 16. At this time, the pressing surface 19Pc descends toward the other end surface 16b of the stator core 16, but does not move in the circumferential direction of the stator core 16. That is, the tip end (pressing surface 19Pc) of the extension end 19Pb does not move in the circumferential direction of the stator core 16 due to the bending molding, and the base end of the extension end 19Pb is the stator core 16. It bends in the circumferential direction. As a result, the extending end portion 19Pb is bent and molded so as to be inclined clockwise CW from the base end side to the tip end side. As shown in FIGS. 14 and 15 (D), the extending end portion 19Pb is bent to a position where the pressing surface 19Pc is substantially parallel to the other end surface 16b of the stator core 16.

During bending molding, the flange portion 102c of the forming jig 102 abuts on the outer peripheral side surface of the extending end portion 19Pb, and supports the extending end portion 19Pb so as not to fall outward in the radial direction of the stator core 16. do. That is, since the extending end portion 19Pb of the sixth layer (outermost layer) does not have another extending end portion 19b adjacent to the outside of the stator core 16 in the radial direction, the flange portion 102c of the forming jig 102 If it does not exist, it tends to incline outward in the radial direction. On the other hand, the extending end portion 19b of the sixth layer (outermost layer) is prevented from being inclined inward in the radial direction by the extending end portion 19b of the fifth layer adjacent to the inner side of the stator core 16 in the radial direction. Will be done.

A set of molding jigs 102 is raised to a position separated from the coil segment 19 after bending molding. Next, by a drive mechanism (not shown), the molding jig 102 is moved inward in the radial direction by one layer and adjusted so as to narrow the distance between the molding jigs 102, and the arrangement diameter of the molding jig 102 is set to the fifth layer. Match the diameter of the extension end 19Qb. In this state, the forming jig 102 is lowered to simultaneously press the pressing surfaces 19Qc of the 48 extending end portions 19Qb located in the fifth layer, and the stator core 16 is rotated clockwise CW. The extension end portion 19Qb of the fifth layer is simultaneously bent along the circumferential direction of the stator core 16.

The forming jig 102 is moved inward in the radial direction of the stator core 16 by a distance corresponding to one layer of the coil segment 19 each time the bending forming of the extending end portion 19b is completed, and the above-mentioned bending forming is performed. Is repeated. The forming jig 102 has a diameter of the stator core 16 after the bending molding of the extension end portion 19b in all the layers (a total of 6 layers from the 6th layer of the outermost layer to the 1st layer of the innermost layer) is completed. It is moved outward in the direction and returns to the position corresponding to the outermost layer.

The extending ends 19Pb, 19Qb, 19Rb, 19Sb, 19Tb and 19Ub are alternately bent and formed in opposite directions along the circumferential direction of the stator core 16. That is, the extending end portions 19Pb (6th layer), 19Rb (4th layer) and 19Tb (2nd layer) are clockwise along the circumferential direction of the stator core 16 from the base end side to the tip end side. It is bent and molded into CW. Further, the extending end portions 19Qb (fifth layer), 19Sb (third layer) and 19Ub (first layer) are counterclockwise from the base end side to the tip end side along the circumferential direction of the stator core 16. It is bent and molded in the direction CCW. The bending direction can be selected by changing the inclination direction of the pressing surface 19c and the rotation direction of the stator core 16.

When the pressing portion 102b of the molding jig 102 presses the pressing surface 19c of the extension end portion 19Ub located on the fifth layer for bending molding, the flange portion 102c of the molding jig 102 is bent and molded. It may come into contact with the extended end portion 19Ub of the sixth layer that has already been completed. In this case, the extension end portion 19b of the sixth layer is pushed by the flange portion 102c and elastically deformed once, but returns to the original bending molding position by springback when the molding jig 102 is separated.

16, FIG. 17, FIG. 18, and FIG. 19 are perspective views showing the steps of bending and molding the extending end portion of the innermost layer, respectively.
As shown in FIG. 16, the set of molding jigs 102 are moved so as to have the narrowest distance from each other, and are adjusted to have a diameter that matches the diameter of the extending end portion 19Ub of the innermost layer. After the adjustment, the forming jig 102 descends in the direction of the central axis of the stator core 16 and simultaneously presses the pressing surfaces Uc of the 48 extending end portions 19Ub located in the innermost layer.

As shown in FIGS. 17 and 18, the pressing portion 102b of the molding jig 102 presses the pressing surface 19Uc of the extending end portion 19Ub downward. At the same time, the stator core 16 is rotated clockwise CW. As a result, the base end portion of the extending end portion 19Ub is bent in the direction opposite to the inclination direction of the pressing surface 19Uc and in the circumferential direction of the stator core 16. The extending end portion 19Ub is bent to a position where the pressing surface 19Uc is substantially parallel to the other end surface 16b of the stator core 16.
During the bending molding, the flange portion 102c of the forming jig 102 supports the side surface of the extending end portion 19Ub on the outer peripheral side, and prevents the extending end portion 19Ub from moving outward in the radial direction and being deformed. Further, during the bending molding, the side surface of the extending end portion 19Ub on the inner peripheral side is supported by the outer peripheral surface 101a of the inner wall jig 101, so that the extending end portion 19Ub can be moved and deformed inward in the radial direction. It is preventing. That is, since the extending end portion 19Ub of the first layer (innermost layer) does not have another extending end portion 19b adjacent to the radial inside of the stator core 16, it is radially inside with the pressing process. However, by pressing the extending end portion 19Ub by the outer peripheral surface 101a of the inner wall jig 101, it is possible to prevent the extending end portion 19Ub from being deformed inward in the radial direction and falling.
After bending and molding the coil segment 19, one set of molding jigs 102 is pulled up above the inner wall jig 101 and separated from the coil segments 19.

When the extension end 19b is bent and molded by the forming jig 102, whether or not the extension end 19b falls outward in the radial direction of the stator core 16 depends on the material of the coil segment 19 and the bending conditions. Depends on. Therefore, if the extension end 19b is difficult to fall outward in the radial direction of the stator core 16 or if the extension end 19b is within the allowable range, the flange portion 102c is omitted from the forming jig. 102 may be used.

Whether or not the extending end portion 19Ub of the first layer (innermost layer) is inclined inward in the radial direction of the stator core 16 depends on the material of the coil segment 19 and the bending conditions. Therefore, the inner wall jig 101 may be omitted when the extension end portion 19Ub of the first layer (innermost layer) is difficult to be deformed inward in the radial direction, or when the deformation is within the permissible range.

FIG. 19 is an enlarged perspective view showing a part of the bent coil segment 19.
As shown in the figure, in a state where the forming jig 102 is separated from the coil segment 19, the extending ends 19Pb, 19Qb, 19Rb, 19Sb, 19Tb, 19Ub of the coil segment 19 are formed by springback after bending and forming. The stator core 16 is slightly misaligned toward the outside in the radial direction. The pressing surfaces 19Pc, 19Qc, 19Rc, 19Sc, 19Tc, and 19Uc are located alternately in the circumferential direction of the stator core 16 and are arranged in a zigzag in the radial direction of the stator core 16. Between the 6th layer pressing surface 19Pc and the 5th layer pressing surface 19Qc, between the 4th layer pressing surface 19Rc and the 3rd layer pressing surface 19Sc, and between the 2nd layer pressing surface 19Tc and the 1st layer. There are slight gaps between the pressing surface 19 Uc and the pressing surface 19 Uc.

Therefore, by bending the extending end portion in the next bending step, the gap between the pressing surfaces is eliminated, and the pressing surfaces are arranged in a line in the radial direction.
FIG. 20 is a perspective view showing a bending process, and FIG. 21 is an enlarged perspective view showing a part of an extension end portion, an inner wall jig, and an outer wall jig in the bending process.
As shown in FIG. 20, in the bending process, the extension end 19b is bent by pressing the extension end 19b from both sides in the radial direction with the inner wall jig 101 and the outer wall jig 103. The outer wall jig 103 is composed of a plurality of ring-shaped members, for example, four arc-shaped dividing jigs 103A, 103B, 103C, and 103D that are divided into four parts. The outer wall jig 103 has an inner peripheral surface 103a that functions as a pressing surface. In a state where the ring-shaped outer wall jig 103 is formed by combining the dividing jigs 103A to 103D, the diameter of the inner peripheral surface 103a is composed of 48 extending end portions 19Pb located in the sixth layer (outermost layer). Slightly smaller than the outer diameter of the cylinder to be made. The dividing jigs 103A to 103D are made of a metal having sufficient rigidity.

As shown in FIGS. 20 and 21, in the bending process, the four dividing jigs 103A, 103B, 103C, and 103D are moved from the outer radial direction toward the inner wall jig 101 by a drive mechanism (not shown) to move the outer wall. On the inner peripheral surface 103a of the jig 103, the extending end portion 19b of the outermost layer is pressed toward the inner wall jig 101 with a predetermined pressure. The extending ends 19Pb, 19Qb, 19Rb, 19Sb, 19Tb and 19Ub of the six layers are sandwiched between the inner peripheral surface 103a of the outer wall jig 103 and the outer peripheral surface 101a of the inner wall jig 101, and are sandwiched from both sides in the radial direction. It is pressed by the outer wall jig 103 and the inner wall jig 101. As a result, at least the tip ends of the 6-layer extension ends 19Pb, 19Qb, 19Rb, 19Sb, 19Tb and 19Ub are bent along the inner peripheral surface 103a of the outer wall jig 103 and the outer peripheral surface 101a of the inner wall jig 101. Be done.

FIG. 22 is a perspective view showing the extending end portion 19b after the bending process is performed. As shown in the figure, by performing the bending process, the extending ends 19Pb, 19Qb, 19Rb, 19Sb, 19Tb and 19Ub of the coil segment 19 are displaced outward in the radial direction and the gap is eliminated, and the pressing surfaces 19Pc and 19Qc are eliminated. , 19Rc, 19Sc, 19Tc, 19Uc are adjacent to each other and are arranged substantially in a line in the radial direction of the stator core 16. As a result, the gap between the 6th layer pressing surface 19Pc and the 5th layer pressing surface 19Qc, the gap between the 4th layer pressing surface 19Rc and the 3rd layer pressing surface 19Sc, and the second layer The gap between the pressing surface 19Tc and the pressing surface 19Uc of the first layer is almost eliminated, and the joining is easy.

FIG. 23 is an enlarged perspective view showing the pressing surface 19c in the region J of FIG. 21.
In the above-mentioned bending process, if a plurality of extending end portions 19b of the stator core 16 are simply sandwiched from both sides in the radial direction with a bending jig, a pressing surface (tip portion) 19c having a higher height than the adjacent portion is adjacent to the pressing surface (tip portion) 19c. It may escape to the upper side of the pressing surface 19c (the pressing surface 19c rides on the surface), the heights of the pressing surfaces 19c may not be uniform, and the extending end portion 19b may not be formed into a desired curved shape. .. Further, since the thickness of the tip of the extending end portion 19b is thin, the area overlapping in the radial direction is small.
Therefore, as described above, according to the present embodiment, the corner portions 19x and 19y on the outer peripheral side of the tip end portion of the extension end portion 19b including each pressing surface 19c are chamfered to form the inclined surfaces 19c1 and 19c2. There is. By providing the inclined surfaces 19c1 and 19c2, it is possible to prevent the pressing surface (tip portion) 19c from riding on the adjacent pressing surface 19c, and to satisfactorily bend the extending end portion 19b. As a result, the heights of the plurality of pressing surfaces 19c can be made uniform, and they can be arranged side by side in the radial direction. Further, the inclined surface 19c1 on the welding side can be brought into close contact with the adjacent extending end portion 19b facing the welding side without a gap, and the area overlapping in the radial direction of the tip portion, that is, the joining area can be increased. On the other hand, the inclined surface 19c2 on the non-welded side has a length L2 longer than that of the inclined surface 19c1 on the weld side, so that there is a slight gap (insulation distance) between the inclined surface 19c2 and the adjacent extending end portion 19b facing each other. ) Can be secured.
Specifically, the portion where the side portion 19Pe of the pressing surface 19Pc of the sixth layer and the inclined surface 19Qc1 provided on the pressing surface 19Qc of the fifth layer are in close contact with each other corresponds to a welding point 19i for welding. Welding is performed with reference to FIG. 24 as described later. Similarly, the portion where the side portion 19Re of the pressing surface 19Rc of the fourth layer and the inclined surface 19Sc1 provided on the pressing surface 19Sc of the third layer are in close contact with each other corresponds to the welding point 19i. Similarly, the portion where the side portion 19Te of the pressing surface 19Tc of the second layer and the inclined surface 19Uc1 provided on the pressing surface 19Uc of the first layer are in close contact with each other corresponds to the welding point 19i.
Further, the inclined surface 19c2 can be used to suppress interference between the pressing surfaces 19c that are not welded. That is, the inclined surface 19c2 is used to prevent the pressing surfaces 19c that are not welded from coming into local contact with each other to form an excessive gap between the pressing surfaces 19c. Specifically, the inclined surface 19Pc2 provided on the pressing surface 19Pc of the sixth layer is located on the outermost layer of all the pressing surfaces 19c, and therefore corresponds to a non-welding point 19j in which welding is not performed. Further, the portion where the side portion 19Qe of the pressing surface 19Qc of the fifth layer and the inclined surface 19Rc2 provided on the pressing surface 19Rc of the fourth layer are in contact with each other corresponds to the non-welding point 19j. Similarly, the portion where the side portion 19Se of the pressing surface 19Sc of the third layer and the inclined surface 19Tc2 provided on the pressing surface 19Tc of the second layer are in contact with each other corresponds to the non-welding point 19j.
Here, on the pressing surface 19c, the inclined surface 19c2 forming the non-welding point 19j may be formed larger than the inclined surface 19c1 forming the welding point 19i. In this case, for example, the side portion 19Qe of the pressing surface 19Qc of the fifth layer and the inclined surface 19Rc2 provided on the pressing surface 19Rc of the fourth layer can be separated from each other. With this configuration, the pressing surfaces 19c that are not welded can be easily electrically insulated from each other.

In the above-mentioned bending molding, whether or not a gap is generated between the pressing surfaces 19c adjacent to each other in the radial direction of the stator core 16 depends on the material of the coil segment 19 and the bending conditions. Depending on the conditions, there may be no gap between the pressing surfaces 19c adjacent to each other in the radial direction of the stator core 16. If there is no gap between the adjacent pressing surfaces 19c or the gap is within the permissible range, the bending process shown in FIG. 20 may be omitted.

After the bending process described above, the two pressing surfaces 19c adjacent to each other in the radial direction are mechanically and electrically joined to each other to form a three-phase coil 18. FIG. 24 is a perspective view showing an example of the joining process, and FIG. 25 is a perspective view showing the joined pressing surface 19c.
According to the present embodiment, as an example, in the joining step, the pressed surfaces are joined by welding with a laser beam. As shown in FIG. 24, the laser beam L is emitted from the laser light source 104 in a state where the bent and molded 6-layer extending end portion 19b is sandwiched between the inner wall jig 101 and the outer wall jig 103, and the galvanometer mirror is used. The laser beam L is irradiated to the pressing surface 19c of the extending end portion 19b via the 107. Specifically, the galvano mirror 105 is driven while the stator core 16 is held at a predetermined position, and the boundary between the 6th layer pressing surface 19Pc and the 5th layer pressing surface 19Qc arranged in a row in the radial direction. Laser light is applied to the boundary portion between the pressing surface 19Rc of the fourth layer and the pressing surface 19Sc of the third layer, and the boundary portion between the pressing surface 19Tc of the second layer and the pressing surface 19Uc of the first layer, respectively. The two adjacent pressing surfaces 19c are partially heated and melted by the laser beam L, respectively, and then agglomerated welding beads 19 g (see FIG. 25) are formed in a fused state. The weld bead 19g mechanically and electrically joins two adjacent pressing surfaces 19c.

After welding a row of pressing surfaces 19c, rotate the stator core 16 in the circumferential direction by 7.5 degrees (360 degrees divided by 48) and then stop. In this state, the galvano mirror 105 is placed at the boundary between the pressing surface 19Pc and the pressing surface 19Qc in the second row, the boundary between the pressing surface 19Rc and the pressing surface 19Sc, and the boundary between the pressing surface 19Tc and the pressing surface 19Uc. Laser light L is irradiated through each of them, and two adjacent pressing surfaces are welded to each other. Such a welding process is repeated to weld two pressing surfaces in all rows arranged in the radial direction. As shown in FIG. 25, by welding and joining two pressing surfaces 19c in each row, a three-phase (U-phase, V-phase and W-phase) coil 18 composed of a plurality of coil segments 19 is formed. ..

In the joining step, the laser welding may be performed by propagating the laser light derived from the semiconductor laser by the optical fiber and condensing the laser light derived from the optical fiber on the pressing surface 19c by the condenser lens. In this case, the condenser lens connected to the optical fiber is moved to the vicinity of the pressing surface 19c of the coil segment 19 by a linear motion stage, a robot hand, or the like. Further, the bonding step is not limited to laser welding, and other bonding methods such as soldering and ultrasonic bonding may be used.

After the joining process is completed, the inner wall jig 101 and the outer wall jig 103 are removed from the stator core 16 and the coil segment 19. Subsequently, the tip end portion and the joint portion (pressing surface) of the extending end portion 19b are coated with powder or covered with an insulating material such as varnish to ensure electrical insulation between the coils 18. Further, a U-phase connection terminal TU, a V-phase connection terminal TV, and a W-phase connection terminal TW are connected to each phase of the coil 18.
Through the above manufacturing process, the coil 18 is mounted and connected to the stator core 16 to form the stator 12.

According to the stator 12 according to the present embodiment configured as described above, the linear portions 19a of the plurality of coil segments 19 provided in the stator 12 are located in the slot 20 in the radial direction of the stator core 16. A plurality of the stator cores 16 are arranged side by side and have an extending end portion 19b extending outward from one end surface 16a of the stator core 16. Each of the extending end portions 19b is bent in the circumferential direction of the stator core 16 so that the pressing surface 19c is along the one end surface 16a, and the plurality of pressing surfaces 19c are arranged side by side in the radial direction of the stator core 16. Two pressing surfaces 19c adjacent to each other in the radial direction are joined to each other, and the inclined surface 19c1 faces the extending end portion 19b adjacent to the outer peripheral side in the radial direction.
Further, according to the method for manufacturing the stator 12 according to the present embodiment, the pressing of one extending end portion (for example, the extending end portion 19Pb of the sixth layer) to be joined adjacent to each other in the radial direction of the stator core 16 is pressed. The side portion 19Pe of the surface 19Pc and the inclined surface 19Qc1 provided on the pressing surface 19Qc of another extending end portion (for example, the extending end portion 19Qb of the fifth layer) are brought into contact with each other, and the contacted portions are welded to each other. This forms the coil 18. In this configuration, at least the inclined surface 19Qc1 of the coil segment 19 is used.
According to the method of manufacturing the stator 12 and the stator 12, the pressing surface 19c of each extending end portion 19b is inclined outward in the radial direction of the stator core 16 due to backlash or the like during molding. Even if the pressing surfaces 19c to be welded are sufficiently close to each other, welding can be performed.
Here, it is possible to bend the extension end 19b without gripping the tip of the extension end 19b. Therefore, it is not necessary to provide the grip portion on the extension end portion 19b of the coil segment 19, and the extension end portion 19b can be set shorter by the amount of the grip portion. Therefore, the protruding height of the coil end 18b of the formed coil 18 (the protruding height from the other end surface 16b of the stator core 16) can be suppressed low. As a result, the coil 18 and the stator 12 can be miniaturized.
From the above, according to the present embodiment, it is possible to obtain a method for manufacturing the stator 12 which can satisfactorily join a plurality of coil segments 19 while achieving miniaturization.
Further, since the inclined surfaces 19c1 and 19c2 are provided at the most advanced portion of the straight portion 19a of the coil segment 19, the straight portion 19a can be easily inserted into the slot 20, and the stator 12 can be easily manufactured. can do.

Further, according to the stator 12 according to the present embodiment, the inclined surfaces 19c1 and 19c2 of the coil segment 19 are located on the outer peripheral surface side of the stator core 16 at the tip of the pressing surface 19c of the pair of straight portions 19a. ing. The boundary portion where one pressing surface 19c adjacent to each other in the radial direction of the stator core 16 and the other pressing surface 19c are joined includes an inclined surface 19c1 or 19c2. Here, the boundary portion corresponds to, for example, the welding point 19i.
Further, according to the method for manufacturing the stator 12 according to the present embodiment, the coil segment 19 having the above configuration is used.
According to the method of manufacturing the stator 12 and the stator 12, for example, the side portion 19Pe of the pressing surface 19Pc located on the sixth layer and the inclined surface 19Qc1 provided on the pressing surface 19Qc located on the fifth layer. While welding by contacting with each other, interference between the side portion 19Qe of the pressing surface 19Qc of the fifth layer and the side portion 19Re of the inclined surface 19Rc2 provided on the pressing surface 19Rc of the fourth layer is suppressed. The coil 18 can be formed. Here, suppressing the interference between the side portion 19Qe of the pressing surface 19Qc and the side portion 19Re of the inclined surface 19Rc2 provided on the pressing surface 19Rc prevents local contact and an excessive gap between them. Intended for configuration. That is, the above-mentioned configuration includes a configuration in which a gap is not formed between the two in a surface contact state and a configuration in which a gap is formed in a slightly separated state. According to the method of manufacturing the stator 12 and the stator 12, the pressing surface 19c of each extending end portion 19b is inclined outward in the radial direction of the stator core 16 due to backlash or the like during molding. Even when the pressing surfaces 19c to be welded are sufficiently brought close to each other for welding, interference between the pressing surfaces 19c that are not welded can be suppressed.

Further, according to the manufacturing method of the present embodiment, when the pressing portion 102b of the molding jig 102 presses the pressing surface 19c of the coil segment 19, the flange portion 102c of the molding jig 102 extends the extending end of the coil segment 19. The portion 19b is supported from the radial outside of the stator core 16. According to such a manufacturing method, when the extending end portion 19b is bent and molded by the forming jig 102, it is possible to prevent the extending end portion 19b from falling outward in the radial direction. As a result, the plurality of pressing surfaces 19c can be arranged without gaps in the radial direction of the stator core 16. That is, for example, the side portion 19Pe of the pressing surface 19Pc of the extending end portion 19Pb of the sixth layer and the inclined surface 19Qc1 provided on the pressing surface 19Qc of the extending end portion 19Qb of the fifth layer can be brought into close contact with each other. .. As a result, the pressing surfaces 19c adjacent to each other in the radial direction of the stator core 16 can be joined well and easily.

Further, according to the manufacturing method of the present embodiment, a plurality of extending end portions 19b which are bent and formed by the outer wall jig 103 and the inner wall jig 101 and arranged in the radial direction of the stator core 16 are formed on the stator core 16. The extension end 19b is curved by pressing from the outside in the radial direction and the inside in the radial direction. According to such a manufacturing method, a plurality of extending end portions 19b arranged in the radial direction of the stator core 16 are curved by the outer wall jig 103 and the inner wall jig 101 to reduce the gap between the plurality of pressing surfaces 19c. For example, the side portion 19Pe of the pressing surface 19Pc of the extending end portion 19Pb of the sixth layer and the inclined surface 19Qc1 provided on the pressing surface 19Qc of the extending end portion 19Qb of the fifth layer are brought into close contact with each other. Can be done. As a result, the pressing surfaces 19c adjacent to each other in the radial direction of the stator core 16 can be joined well and easily.

Although the embodiment of the present invention has been described, this embodiment is presented as an example and is not intended to limit the scope of the invention. The embodiment can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and modifications are included in the scope and gist of the invention, as well as in the scope of the invention described in the claims and the equivalent scope thereof.
For example, as shown in FIG. 26, the tip end portion of the coil segment 19 is limited to the inclined surface 19c1 of the outer peripheral side corner portion 19x (shown by the broken line) at the tip end (including the pressing surface 19c) of one straight line portion 19a. Instead, the inclined surface 19c3 may also be provided at the corner portion 19z (shown by the broken line) on the inner peripheral side. Similarly, at the tip of the other straight portion 19a (including the pressing surface 19c), the tip portion of the coil segment 19 is inclined not only on the inclined surface 19c2 of the corner portion 19y on the outer peripheral side but also on the corner portion on the inner peripheral side. It may have a surface.
The number of turns of the stator coil and the number of coil segments installed are not limited to the above-described embodiments, and can be increased or decreased as appropriate. For example, it may be configured so that four or eight segment straight portions are arranged in one slot. The dimensions, materials, shapes, etc. of the rotor are not limited to the above-described embodiments, and can be variously changed according to the design. The rotor and the rotary electric machine according to the present embodiment can be applied not only to a permanent magnet field motor but also to an induction motor.

10 ... rotary electric machine, 12 ... stator, 16 ... stator core, 16a ... one end surface, 16b ... other end surface,
18 ... Coil, 18a, 18b ... Coil end,
19, 19P, 19Q, 19R, 19S, 19T, 19U ... Coil segment,
19a ... Straight line part,
19b, 19Pb, 19Qb, 19Rb, 19Sb, 19Tb, 19Ub ... Extension end,
19c, 19Pc, 19Qc, 19Rc, 19Sc, 19Tc, 19Uc ... Pressing surface,
19c1, 19Qc1, 19Sc1, 19Uc1, 19c2, 19Pc2, 19Rc2, 19Tc2, 19c3 ... Inclined surface,
19Pe, 19Qe, 19Re, 19Se, 19Te ... Side,
19d ... Cross-linked part, 19f ... Insulating film, 19g ... Welding bead, 19i ... Welding point,
19j ... non-welding point, 19x, 19y, 19z ... corner, 20 ... slot 101 ... inner wall jig, 101a ... outer peripheral surface, 102 ... molding jig (pressing jig),
102a ... main body, 102b ... pressing, 102c ... flange,
103 ... outer wall jig, 103A, 103B, 103C, 1053 ... split jig,
103a ... Inner peripheral surface, 104 ... Laser light source, 105 ... Galvano mirror

Claims (6)

1. A stator core having one end surface located at one end in the axial direction, the other end surface located at the other end in the axial direction, and a plurality of slots extending in the axial direction and opening to the one end surface and the other end surface, respectively. When,
   A plurality of coil segments, each of which is mounted in the slot and joined to each other to form a multi-phase coil, are provided.
   Each of the coil segments is formed of a flat conductor, and is provided at the other end of the straight line portion, a pair of straight line portions facing each other at intervals, a bridge portion connecting one ends of the straight line portions to each other, and the straight line portion. It integrally has a pressing surface inclined with respect to the axial direction of the portion and an inclined surface formed by chamfering at least one corner of the tip of the straight portion including the pressing surface.
   A plurality of the straight portions of the plurality of coil segments are arranged side by side in the radial direction of the stator core in the slot, and have an extending end portion extending outward from the one end surface of the stator core. ,
   Each of the extending end portions is bent in the circumferential direction of the stator core so that the pressing surface is along the one end surface, and the plurality of pressing surfaces are arranged side by side in the radial direction of the stator core. The stator is formed so that two pressing surfaces adjacent to each other in the radial direction are joined to each other, and the inclined surface faces the extending end portion adjacent to the outer peripheral side in the radial direction.
2. Each of the inclined surfaces is located on the outer peripheral surface side of the stator core, and at a boundary portion where one pressing surface adjacent to the stator core in the radial direction and the other pressing surface are joined. The stator according to claim 1, wherein the inclined surface is included.
3. A pair of straight portions formed of flat conductors that face each other at intervals, a cross-linked portion that connects one ends of the straight portions to each other, and a bridge portion that is provided at the other end of the straight portions and is provided in the axial direction of the straight portion. A plurality of coil segments having an inclined pressing surface and an inclined surface formed by chamfering at least one corner of the tip of the straight line portion including the pressing surface are prepared.
   The straight portions of the plurality of coil segments having the inclined surface positioned radially outside the stator core are inserted into the plurality of slots from one end surface side of the stator core, and the other end surface side of the stator core. By forming a plurality of extending ends protruding in the axial direction from the above and arranging a plurality of the straight portions arranged in the radial direction in each slot, the extending ends are coaxial with the stator core. Arranged in a multi-layered cylindrical shape,
   While pressing the pressing surface toward the other end surface in the axial direction of the stator core by the pressing portion of the pressing jig, at least one of the stator core and the pressing jig is rotated in the circumferential direction. How to make a stator.
4. The side portion of the pressing surface of one extending end portion to be joined adjacent to each other in the radial direction of the stator core and the inclined surface provided on the pressing surface of the other extending end portion are in contact with each other. Let me
   The pressing surface of one of the extending ends and the pressing surface of the other extending end are joined to each other, and at the same time.
   Each of the inclined surfaces is located on the outer peripheral surface side of the stator core, and at a boundary portion where one pressing surface adjacent to the stator core in the radial direction and the other pressing surface are joined. The method for manufacturing a stator according to claim 3, wherein the coil segment including the inclined surface is used.
5. When the pressing surface is pressed by the pressing portion of the pressing jig,
   The method for manufacturing a stator according to claim 3, wherein the extending end portion is supported from the radial outside of the stator core by a flange portion of the pressing jig.
6. According to claim 3, a plurality of the extending ends formed by bending and forming in the radial direction of the stator core by an outer wall jig and an inner wall jig are pressed from the radial outside and the radial inside of the stator core. The method for manufacturing the stator described.

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