JP7733717B2 - Conductor forming method - Google Patents

Description

The present invention relates to a conductor forming method.

Conventionally, a conductor forming method has been known in which a straight conductor wire is folded back to form a conductor having multiple straight sections and angled coil end sections that connect the ends of adjacent straight sections (see, for example, Patent Document 1).

The above-mentioned conductor forming method first involves bending a straight conductor wire diagonally to form a diagonal section, and then folding the conductor wire back 180 degrees using the center of the diagonal section as a fulcrum to form a mountain-shaped coil end section.

Japanese Patent Application Laid-Open No. 2021-058076

In recent years, electric vehicles (BEVs: Battery Electric Vehicles) have become known, which do not have internal combustion engines and are driven solely by rotating electric machines. Electric vehicles generally have smaller rotating electric machines than hybrid electric vehicles (HEVs: Hybrid Electric Vehicles). To make rotating electric machines more compact, it is necessary to reduce the diameter of the stator, and measures to achieve this are being sought.

In the above-mentioned conventional technology, the portion of the conductor wire that will become the coil end is bent at an angle, and then the bent portion is folded back 180 degrees around the center of the bent portion as a fulcrum to form the coil end. However, with this method, the apex of the formed coil end is made wide. Therefore, when a long strip-shaped coil is formed using this method, adjacent coil end portions along the length of the strip-shaped coil interfere with each other when the strip-shaped coil is wound. This makes it difficult to wind the strip-shaped coil to a small diameter in order to fit it onto a small-diameter stator core.

The objective of the present invention is to provide a conductor forming method that can suppress the widthwise expansion of the apex of the coil end portion, enabling winding with a smaller diameter.

(1) The conductor forming method according to the present invention is a conductor forming method for forming a conductor (e.g., conductor 100 described below) having a mountain-shaped coil end portion (e.g., coil end portion 102 described below) and straight portions (e.g., straight portions 101 described below) connected to both ends of the coil end portion by folding back a conductor wire (e.g., conductor wire 1 described below), and includes a folding back process for folding back the conductor wire at a fulcrum at a portion corresponding to the vertex of the coil end portion (e.g., vertex 102b described below). and a slanting process in which, after the folding process begins, the conductor wire on one side to be folded is moved relative to the conductor wire on the other side to be folded in a direction (e.g., the X1 direction described below) that intersects with the extension direction of the straight portion (e.g., the Y direction described below) using a portion of the conductor corresponding to the boundary between the coil end portion and the straight portion (e.g., boundary 103 described below) as a fulcrum, and the conductor wire is slanted around the vertex to form the coil end portion.

(2) In the conductor forming method described in (1) above, the oblique movement step is performed in a state in which the conductor wire on one side to be folded back and the conductor wire on the other side to be folded back do not completely overlap after the start of the folding step.

(3) In the conductor forming method described in (1) or (2) above, the folding process and the oblique process are sequentially repeated multiple times for multiple conductor wires arranged in parallel at regular intervals, thereby forming the coil end portions on both ends of the straight portion in the extension direction and forming the strip-shaped conductor (for example, the strip-shaped coil described below).

(4) In the conductor forming method described in (3) above, the multiple folding steps include at least one step of folding the multiple conductor wires in a direction opposite to the folding direction of the previous folding step.

According to (1) above, after the conductor wire folding process begins, the conductor wire is angled to form the coil end portion, which prevents the apex of the formed coil end portion from expanding in the width direction. As a result, the conductor formed in this way can be wound with a smaller diameter.

According to (2) above, the conductor wires are angled before they completely overlap after the folding process begins, so a guide jig can be inserted to form the starting point for the fold before the conductor wires begin to be angled.

According to (3) above, the widthwise expansion of the apex of the coil end portion is suppressed, resulting in a strip-shaped coil that can be wound with a small diameter.

According to (4) above, interference between layers can be avoided at the layer transition points of the wound strip-shaped conductor.

1 is a front view showing an example of a conductor formed by the conductor forming method of the present embodiment. FIG. 2 is a plan view showing a stator on which conductors are mounted. 10A to 10C are diagrams illustrating a method for forming a U-shaped conductor wire. FIG. 4 is a cross-sectional view taken along line AA in FIG. 3. FIG. 10 is a front view showing the state in which the conductor wires are overlapped. 1 is a perspective view showing an example of a conductor shaping device for carrying out the conductor shaping method of the present embodiment. FIG. FIG. 3 is a perspective view showing a part of the gripping device before gripping the conductor wire. FIG. 10 is a perspective view showing a part of the gripping device after gripping the conductor wire. 1A to 1C are diagrams illustrating a conductor shaping method using a conductor shaping device. FIG. FIG. 1A to 1C are diagrams illustrating a conductor shaping method using a conductor shaping device. 10 is a side view showing a state in which the conductor wire is bent with the guide jig sandwiched therebetween. FIG. 1A to 1C are diagrams illustrating a conductor shaping method using a conductor shaping device. 1A to 1C are diagrams illustrating a conductor shaping method using a conductor shaping device. 1A to 1C are diagrams illustrating a conductor shaping method using a conductor shaping device. 1A to 1C are diagrams illustrating a conductor shaping method using a conductor shaping device. 1A to 1C are diagrams illustrating a conductor shaping method using a conductor shaping device. 1A to 1C are diagrams illustrating a conductor shaping method using a conductor shaping device. 1A to 1C are diagrams illustrating a conductor shaping method using a conductor shaping device. 1A to 1C are diagrams illustrating a conductor shaping method using a conductor shaping device. FIG. 4 is an enlarged view showing a coil end portion of the conductor after forming. FIG. 4 is a plan view showing a coil end portion of the conductor after forming. 1A to 1C are diagrams illustrating a conductor shaping method using a conductor shaping device. 1A to 1C are diagrams illustrating a conductor shaping method using a conductor shaping device. FIG. 2 is a plan view schematically showing a conductor having a layer change portion.

Embodiments of the present invention will now be described in detail with reference to the drawings. Figure 1 shows an example of a conductor 100 formed by the conductor forming method of this embodiment. The conductor 100 is formed by bending multiple conductor wires 1. The conductor 100 of this embodiment is a strip-shaped coil composed of six conductor wires 1 and formed into a long strip in one direction (the X direction in Figure 1).

The directions shown in the figures are defined as follows: The X direction is the length direction of the conductor 100. This X direction corresponds to the width direction of the conductor wire 1 that makes up the conductor 100. The Y direction is the width direction of the conductor 100. This Y direction corresponds to the extension direction of the straight portions 101 of the conductor 100 and also corresponds to the length direction of the conductor wire 1. The Z direction is the thickness direction of the conductor 100. This Z direction corresponds to the thickness direction of the conductor wire 1. The X, Y, and Z directions in each figure correspond to the X, Y, and Z directions of the conductor 100, respectively.

The conductor 100 has multiple straight sections 101 arranged in parallel at regular intervals along its length, and multiple coil end sections 102 arranged at both ends of each straight section 101 in the extension direction. The straight sections 101 extend along the width direction of the conductor 100. The coil end sections 102 connect one end and the other end of every fifth straight section 101, 101, alternately in a mountain shape along the length of the conductor 100.

The coil end portion 102 is formed in a mountain shape, with an inclined portion 102a extending diagonally from the boundary portion 103 with the straight portion 101, and an apex 102b where the tips of the inclined portions 102a, 102a connected to the two straight portions 101, 101 are connected. In the conductor 100, the straight portions 101, 101 formed by the two legs 12, 12 of the outer conductor wire 1 of each double-structure conductor wire 1, 1 are arranged every sixth line along the length of the conductor 100, and the straight portions 101, 101 formed by the two legs 12, 12 of the inner conductor wire 1 are arranged every fifth line along the length of the conductor 100.

As shown in Figure 2, the conductor 100 is attached to the stator core 31 to form the stator 3 of a rotating electrical machine. The stator core 31 has multiple teeth 33 that protrude radially toward an axial hole 32 that penetrates in the axial direction (perpendicular to the plane of the paper in Figure 2). Multiple slots 34 that open toward the axial hole 32 are formed between adjacent teeth 33 in the circumferential direction. The conductor 100 is attached so that it wraps around the stator core 31 multiple times by sequentially inserting the straight portions 101 into the slots 34. The coil end portions 102 of the conductor 100 protrude outward on both axial sides of the stator core 31.

The conductor wire 1 that constitutes the conductor 100 is a continuous line that runs uninterrupted along the length of the conductor 100. As shown in Figure 3, the straight conductor wire 1 is bent approximately at its center by a drawing tool 300. As a result, the conductor wire 1 is formed into a U-shape having one U-shaped portion 11 and a pair of straight leg portions 12, 12.

As shown in Figure 4, each conductor wire 1 is composed of multiple flat wires 1a. The flat wires 1a are metal wires, such as copper wires, with a roughly rectangular cross section. The surfaces of the flat wires 1a are covered with a resin insulating coating (not shown). In this embodiment, the conductor wire 1 is a divided wire in which two flat wires 1a, 1a are arranged side by side in the width direction of the conductor wire 1 so that they are in close contact. The conductor wire 1 is bent by the drawing tool 300 in the width direction of the conductor wire 1, which is the direction in which the flat wires 1a, 1a are arranged side by side.

As shown in Figure 5, each U-shaped conductor wire 1 is doubled up, with two wires arranged on the inside and two wires on the outside, with the U-shaped portions 11 aligned on the same side. Similarly, three pairs of doubled conductor wires 1, 1 are stacked, offset in the width direction, so that the 12 legs 12 are aligned parallel to each other at regular intervals. This forms a conductor wire group 10 consisting of six U-shaped conductor wires 1. The conductor wire group 10 is formed into a conductor 100 using a conductor forming device 200 shown in Figure 6.

Figure 6 shows an overview of the configuration of the main parts of a conductor shaping device 200 according to one embodiment. The conductor shaping device 200 includes at least four gripping devices 210A, 210B, 210C, and 210D. The gripping devices 210A, 210B, 210C, and 210D are configured to be able to grip and release all 12 legs 12 of a conductor wire group 10 at once. Because the gripping and release configurations of the four gripping devices 210A, 210B, 210C, and 210D are identical, the configuration of one gripping device 210 will be described with reference to Figures 7 to 9.

As shown in FIG. 7, the gripping device 210 is a rectangular parallelepiped formed long enough to span the 12 legs 12 arranged on the conductor wire group 10. The gripping device 210 has a fixed block 211 extending along the length of the gripping device 210 and 12 movable blocks 212.

8 and 9, the fixed block 211 has twelve grooves 211a that accommodate the twelve legs 12 of the conductor wire group 10. The twelve movable blocks 212 are accommodated in the grooves 211a of the fixed block 211, movably along the X direction in the figure, leaving gaps G into which the legs 12 can fit. The gripping device 210 simultaneously moves all of the movable blocks 212 in the grooves 211a in the directions indicated by the white arrows in FIG. 8 by driving a drive mechanism (not shown). As a result, the gripping device 210 clamps and grips the legs 12 of the conductor wire group 10 that fit into each gap G between the fixed block 211 and the movable block 212. The gripping direction of the legs 12 by the gripping device 210 is the parallel direction of the two rectangular wires 1a, 1a that make up the conductor wire 1. Therefore, the gripping device 210 grips the leg portion 12 of the conductor wire 1 by clamping it in the width direction of the conductor wire 1.

The four gripping devices 210A, 210B, 210C, and 210D are arranged parallel to one another and spaced apart in the length direction (Y direction) of the conductor wire group 10 on the same side in the thickness direction (Z direction) of the conductor wire group 10. The conductor shaping device 200 shown in Figure 6 shows the initial position of the shaping process. At this time, gripping device 210A is arranged near each U-shaped portion 11 of the conductor wire group 10. Grip device 210B is arranged at a predetermined distance from gripping device 210A, farther from each U-shaped portion 11 of the conductor wire group 10 than gripping device 210A. Grip device 210C is arranged at a predetermined distance from gripping device 210B, farther from each U-shaped portion 11 of the conductor wire group 10 than gripping device 210B. The gripping device 210D is positioned at a predetermined distance from the gripping device 210C, farther from the U-shaped portions 11 of the conductor wire group 10 than the gripping device 210C.

As shown in FIG. 6, there is an equal distance L between side edge E1 of gripping device 210A and side edge E2 of gripping device 210B, and between side edge E1 of gripping device 210C and side edge E2 of gripping device 210D. Side edges E1 and E2 are two side edges of gripping devices 210A, 210B, 210C, and 210D that are arranged parallel to the plane that grips the leg portion 12. In gripping devices 210A, 210B, 210C, and 210D, side edge E1 is the side edge closer to the U-shaped portion 11 of the conductor wire group 10, and side edge E2 is the side edge farther from the U-shaped portion 11 of the conductor wire group 10. Distance L is substantially the same as the length L of the straight portion 101 of the conductor 100 shown in FIG. 1 in the extension direction.

The region of the conductor wire group 10 between side edge E2 of gripping device 210A and side edge E1 of gripping device 210B, and the region between side edge E1 of gripping device 210C and side edge E2 of gripping device 210D each constitute a straight portion forming region 10A for forming the straight portion 101 of the conductor 100. Therefore, gripping devices 210A, 210B and gripping devices 210C, 210D each grip 12 legs 12 within the straight portion forming region 10A of the conductor wire group 10. In the leg portions 12 of the conductor wire group 10 shown in Figure 6, the straight portion forming region 10A is shown in white.

The region of the conductor wire group 10 between the side edge E2 of the gripping device 210B and the side edge E1 of the gripping device 210C constitutes the coil end portion forming region 10B for forming the coil end portion 102 of the conductor 100. In the leg portion 12 of the conductor wire group 10 shown in Figure 6, the coil end portion forming region 10B is indicated by hatching.

The straight portion forming regions 10A and the coil end portion forming regions 10B are arranged alternately from the U-shaped portion 11 side of the conductor wire group 10 along the length direction (Y direction) of the leg portion 12.

Of the four gripping devices 210A, 210B, 210C, and 210D, the two gripping devices 210A and 210B closest to the U-shaped portion 11 of the conductor wire group 10 are driven by a rotation mechanism (not shown) so that they can rotate forward and backward around a virtual fold line 220 (shown in FIG. 6) while maintaining the distance L. The fold line 220 is set along the X direction in FIG. 6 at an intermediate position between gripping devices 210B and 210C. This intermediate position corresponds to the position of the vertex 102b of the coil end portion 102 after the conductor wire group 10 has been folded. The fold line 220 is oriented perpendicular to the longitudinal direction of the leg portion 12 and parallel to the longitudinal direction of the four gripping devices 210A, 210B, 210C, and 210D. The gripping devices 210A and 210B gripping the leg portions 12 of the conductor wire group 10 rotate around the folding line 220 as an axis, causing the conductor wire group 10 to fold back at the center of the coil end portion forming region 10B between the gripping devices 210B and 210C. This completes the folding process.

Gripping devices 210A and 210B are arranged to be movable in parallel relative to gripping devices 210C and 210D along the X direction in FIG. 6 while maintaining a distance L by driving a tilting mechanism (not shown). In the conductor shaping device 200 of this embodiment, gripping devices 210C and 210D are arranged to be immovable in the X direction, and gripping devices 210A and 210B are arranged to be movable in parallel in the X direction. However, gripping devices 210A and 210B may be arranged to be immovable in the X direction, and gripping devices 210C and 210D may be arranged to be movable in parallel in the X direction. Furthermore, gripping devices 210A and 210B and gripping devices 210C and 210D may be arranged to be movable in parallel in opposite directions. The gripping devices 210A and 210B gripping the leg portions 12 of the conductor wire group 10 move parallel to the X direction relative to the gripping devices 210C and 210D, so that the coil end portion forming region 10B of the conductor wire group 10 between the gripping devices 210B and 210C is bent so as to be inclined obliquely relative to the longitudinal direction of the leg portions 12. This completes the oblique movement process.

Next, a method for forming a conductor 100 from a conductor wire group 10 using the conductor forming device 200 will be described with reference to Figures 6 and 10 to 22.

First, as shown in FIG. 6, the conductor shaping device 200 grips the 12 leg portions 12 of the conductor wire group 10 using four gripping devices 210A, 210B, 210C, and 210D (gripping process). Then, as shown in FIG. 10, the gripping devices 210A and 210B are driven by a rotation mechanism (not shown) to rotate in the R1 direction around the folding line 220 as an axis. This initiates the folding process for the coil end portion forming region 10B of the conductor wire group 10 that is closest to the U-shaped portion 11.

Although not shown in Figure 10, a guide jig 230 is used in the folding process before the inclined feeding process, described below, is started, as shown in Figures 11 and 12. As shown in Figure 12, the guide jig 230 is formed in a roughly triangular wedge shape that is inclined at an angle of approximately 5° when viewed from the side. The guide jig 230 is inserted between the conductor wire group 10 on one side (the conductor wire group 10 held by gripping devices 210A and 210B) and the conductor wire group 10 on the other side (the conductor wire group 10 held by gripping devices 210C and 210D) that are folded back at the folding line 220.

The leading edge 230a of the guide jig 230 is positioned so as to be parallel to the fold line 220. By positioning the guide jig 230, the starting point of the fold of the leg portion 12 of each conductor wire 1 is supported along the leading edge 230a when the conductor wire group 10 is folded along the fold line 220. This stabilizes the position of the fulcrum P (see Figures 12 and 14) during rotation during the folding process. The fulcrum P corresponds to the apex 102b of the coil end portion 102 of the conductor 100. Since the apex 102b of the coil end portion 102, which is folded into a substantially U-shape in a later process, can be made smaller in diameter, it is possible to form a apex 102b with a small thickness. Note that the leading edge 230a of the guide jig 230 is slightly offset by a distance D toward the gripping device 210C relative to the fold line 220 to ensure smooth folding of each leg portion 12.

At the beginning of the folding process, as shown in FIG. 13, the conductor wire group 10 is folded back along the folding line 220. Therefore, the conductor wire group 10 on one side to be folded back and the conductor wire group 10 on the other side are bent with the guide jig 230 between them in a direction such that the legs 12 of the same conductor wires 1 overlap each other (primary folding process).

As shown in Figure 14, the primary folding process ends when the leg portions 12 of the conductors 1 constituting the folded conductor wire group 10 approach the upper surface 230b of the guide jig 230. Specifically, the gripping devices 210A and 210B rotate 150° from the state shown in Figure 6 around the folding line 220 to fold the conductor wire group 10. After the primary folding process ends, the guide jig 230 retreats from between the folded conductor wire group 10. The guide jig 230 is not shown in Figure 12. Furthermore, the four gripping devices 210A, 210B, 210C, and 210D are not shown in Figure 13 and subsequent figures.

After the primary folding process is completed, the gripping devices 210A and 210B move parallel to the X1 direction as shown in Figure 14, while maintaining the rotation angle at the end of the primary folding process. The X1 direction is the direction along the width direction of the conductors 1 that make up the conductor wire group 10. The X1 direction is parallel to the folding line 220.

By moving the gripping devices 210A and 210B in parallel, the legs 12 of the conductor wires 1 constituting the conductor wire group 10 in the coil end portion forming region 10B are tilted so that the tilt directions intersect in a mountain shape, with the fulcrum P at the time of folding as the boundary. This starts the tilting process.

When the slanting process begins, the leg 12 of each conductor wire 1 forms a coil end portion 102 with two inclined portions 102a, 102a that intersect diagonally with the vertex 102b, with the fulcrum P for folding being the vertex 102b (primary slanting process).

In the primary slanting process, the leg portion 12 is slanted using the side edge E2 of the gripping device 210B and the side edge E1 of the gripping device 210C, which are positioned on either side of the coil end portion forming region 10B, as fulcrums. These fulcrums correspond to the boundary 103 between the coil end portion 102 and the straight portion 101. However, in the coil end portion 102 formed by the primary slanting process, the intersection angle between the two slanted portions 102a, 102a, with vertex 102b as the boundary, is still smaller than in the coil end portion 102 of the finished conductor 100 shown in Figure 1.

After the primary skew process is completed, as shown in FIG. 16, gripping devices 210A and 210B further rotate in the R1 direction around the fold line 220 as an axis so as to overlap gripping devices 210C and 210D. From the state shown in FIG. 6, gripping devices 210A and 210B rotate 180° around the fold line 220 as an axis, folding back the conductor wire group 10. This completely folds back the conductor wire group 10 (secondary folding process).

Once the secondary folding process is complete, the folding process for the first coil end portion forming region 10B of the conductor wire group 10 is complete.

After the folding process is completed, the gripping devices 210A, 210B are translated in the X1 direction, the same as in the primary oblique process, as shown in FIG. 17, while maintaining the rotation angle at the end of the secondary folding process. The translation of the gripping devices 210A, 210B forms coil end portions 102 in the conductor wires 1 that make up the conductor wire group 10, each having the same shape as the coil end portion 102 of the finished conductor 100 shown in FIG. 1 (secondary oblique process).

Once the secondary slanting process is complete, the slanting process for the first coil end portion forming region 10B of the conductor wire group 10 is complete.

After the folding process for the first coil end portion forming region 10B of the conductor wire group 10 begins, the primary folding process, primary oblique process, secondary folding process, and secondary oblique process are performed in sequence as described above, and then the gripping devices 210A, 210B, 210C, and 210D each release their grip on the leg portion 12 of the conductor wire 1. Furthermore, the gripping devices 210A and 210B return to their initial positions shown in FIG. 6.

The conductor wire group 10 is then transported a predetermined distance in the Y1 direction, as shown in FIG. 18, by driving a transport mechanism (not shown) of the conductor shaping device 200. The Y1 direction is along the length of the conductors 1 that make up the conductor wire group 10. The Y1 direction is perpendicular to the folding line 220. As a result, the conductor wire group 10 is transported to a position where the 12 leg portions 12 in the straight portion forming region 10A that were held by the gripping devices 210C and 210D in the previous process can be held by the gripping devices 210A and 210B, which have returned to their initial positions (transportation process).

After the conveying process, as shown in Figures 19 to 22, the coil end portion forming region 10B between the gripping device 210B and the gripping device 210C that have newly gripped the conductor wire group 10 is sequentially subjected to the primary folding process, primary slanting process, secondary folding process, and secondary slanting process, as described above.

The coil end portions 102 formed in this way are neatly arranged in the longitudinal direction of the conductor 100, as shown in Figure 23. The coil end portions 102 are formed by diagonally bending the conductor wire 10 after starting the folding process on the conductor wire 10, so the conductor wire 10 at the vertices 102b is bent into a roughly U-shape in the thickness direction of the conductor 100. Therefore, compared to conventional methods in which the conductor wire 10 is folded back after being diagonally bent, the width W of the vertices 102b of the coil end portions 102 shown in Figure 24 is less likely to increase. Because the distance between adjacent vertices 102b can be made smaller, the conductor 100 can be wound with a smaller diameter than conventional methods, allowing for the construction of a smaller-diameter stator 3.

The conductor wires 1 that make up the conductor wire group 10 are formed at an angle in the oblique process before they completely overlap after the folding process begins, which prevents twisting of the vertices 102b of the coil end portions 102. This effectively prevents the width W of the vertices 102b from expanding.

Since the conductor 100 is formed by folding the conductor wire group 10 back, it has a two-layer structure in which two straight sections 101, 101 are stacked in the thickness direction of the conductor 100. When the conductor 100 is wound around the stator core 31 multiple times, a layer transition section Ta is formed where the layer (turn) changes in the radial direction of the stator core 31 for each turn of the stator core 31. In this case, to avoid interference between layers at the layer transition section Ta in the conductor 100, it is preferable to fold the coil end portion forming region 10B of the conductor wire group 10 corresponding to the layer transition section Ta of the conductor 100 back in the opposite direction (direction R2) from the folding direction (direction R1) of the previous coil end portion forming region 10B, as shown in Figures 25 and 26.

More specifically, as shown in FIG. 25, the coil end portion forming region 10B of the conductor wire group 10 corresponding to the layer change portion Ta of the conductor 100 is transported to a position where it can be folded back. Then, as shown in FIG. 26, the gripping devices 210A, 210B are rotated in the R2 direction, thereby folding back the coil end portion forming region 10B in the opposite direction to the previous process. This rotation in the R2 direction folds back the coil end portion forming region 10B of the conductor wire group 10 corresponding to the layer change portion Ta of the conductor 100. As a result, as shown in FIG. 27, the offset direction in the thickness direction of the conductor 100 attached to the stator core 31 is reversed at each layer change portion Ta.

Figure 27 shows a schematic plan view of the conductor 100 wound four times around the stator core 31. The conductor 100 has two straight sections 101, 101 stacked in the thickness direction, resulting in an eight-turn configuration (1T to 8T) and four layer transition sections Ta. At each layer transition section Ta, the offset direction of the conductor 100 is reversed, so no steps are formed at the layer transition sections Ta when the conductor 100 is wound around the stator core 31. This allows the conductor 100 to be wound with an even smaller diameter.

REFERENCE SIGNS LIST 1 conductor wire 100 conductor 101 straight portion 102 coil end portion 102b apex 103 boundary portion 230 guide jig

Claims (3)

A conductor forming method for forming a conductor having a mountain-shaped coil end portion and straight portions connected to both ends of the coil end portion by folding back a conductor wire, comprising:
a primary folding process in which the conductor wire is folded back using a portion of the conductor wire corresponding to the apex of the coil end portion as a fulcrum , and the folding back process is terminated before one side of the conductor wire to be folded back completely overlaps the other side of the conductor wire to be folded back ;
a primary oblique movement step, after completion of the primary folding step, of moving the conductor wire on one side to be folded back relative to the conductor wire on the other side to be folded back in a direction intersecting with the extending direction of the straight portion, using a portion of the conductor corresponding to a boundary between the coil end portion and the straight portion as a fulcrum, so as to obliquely move the conductor wire with respect to the vertex;
a secondary folding process in which, after the primary oblique folding process is completed, the conductor wire on one side to be folded back is further folded back so as to overlap the conductor wire on the other side to be folded back;
and a secondary oblique step of, after completion of the secondary folding step, further moving the conductor wire on one side to be folded back relative to the conductor wire on the other side to be folded back in the same direction as the primary oblique step , thereby forming the coil end portion. 2. The conductor forming method according to claim 1, wherein the first folding process , the first oblique process, the second folding process, and the second oblique process are sequentially repeated multiple times for a plurality of the conductor wires arranged in parallel at regular intervals, thereby forming the coil end portions at both end sides in the extension direction of the straight portion, and forming the band-shaped conductor. 3. The conductor shaping method according to claim 2, wherein the plurality of primary folding steps and secondary folding steps include at least one step of folding the plurality of conductor wires in a direction opposite to the folding direction of the previous primary folding step and secondary folding step .