JP-7856692-B2 - Method for bending segment coils and apparatus for bending segment coils

JP7856692B2JP 7856692 B2JP7856692 B2JP 7856692B2JP-7856692-B2

Inventors

木村泰之
宮下圭太
茂野淳也
齊藤幹人

Assignees

本田技研工業株式会社

Dates

Publication Date: 20260511
Application Date: 20240322

Claims (8)

A method for bending segment coils, wherein the coil ends of a plurality of segment coils inserted into the stator core of a rotating electric machine are twisted and bent in the circumferential direction of the stator core, A first operation involves twisting and bending a first coil end row, which consists of multiple first coil ends arranged in the circumferential direction, in one direction within the circumferential direction, The first operation is performed in parallel with the first operation, and includes a second operation in which a plurality of second coil ends, which are arranged in the circumferential direction and consist of a plurality of second coil ends adjacent to the first coil end row in the radial direction of the stator core, are twisted and bent in a direction other than the circumferential direction, A method for bending a segment coil, wherein the second operation is started after the first operation has begun but before the first operation has ended, and the timing at which the first coil end row reaches the completed position by the first operation is different from the timing at which the second coil end row reaches the completed position by the second operation.
In the method for bending a segment coil according to claim 1, A method for bending a segment coil, wherein the second operation is started after a predetermined time difference from the start of the first operation.
In the method for bending a segment coil according to claim 2, The second coil end row is positioned radially outward from the stator core than the first coil end row. During the progress of the first and second operations, the multiple first coil ends and the multiple second coil ends pass each other in sequence. A method for bending a segment coil, wherein the time difference is such that when the plurality of first coil ends and the plurality of second coil ends first pass each other, peeling of the coatings of the plurality of first coil ends and the plurality of second coil ends can be prevented.
In the method for bending a segment coil according to claim 3, A method for bending a segment coil, wherein the rotation angle of the second coil end row in the circumferential direction, with respect to the starting position of the second operation when the plurality of first coil ends and the plurality of second coil ends first pass each other, is 2.0° or more.
A segment coil bending apparatus that performs a first operation to twist and bend a first coil end row, consisting of a plurality of first coil ends arranged in the circumferential direction of the stator core, from among a plurality of coil ends that protrude from the stator core of a plurality of segment coils inserted into the stator core of a rotating electric machine, in a first direction which is one of the circumferential directions, and in parallel with the first operation to twist and bend a second coil end row, consisting of a plurality of second coil ends arranged in the circumferential direction, from among the plurality of coil ends, in a second direction which is the other of the circumferential directions, wherein the second coil end row consists of a plurality of second coil ends arranged in the circumferential direction and is adjacent to the first coil end row in the radial direction of the stator core, A first jig that engages with the first coil end row, A second jig that engages with the second coil end row, A first drive unit that rotates the first jig in the first direction to perform the first operation, A second drive unit rotates the second jig in the second direction to perform the second operation, The system comprises a control unit that controls the first drive unit and the second drive unit, The control unit starts the second operation after the start of the first operation but before the end of the first operation, and makes the timing at which the first coil end row reaches the completed position by the first operation and the timing at which the second coil end row reaches the completed position by the second operation different, in a segment coil bending apparatus.
In the segment coil bending apparatus according to claim 5, The control unit is a segment coil bending apparatus that starts the second operation after a predetermined time difference from the start of the first operation.
In the segment coil bending apparatus according to claim 6, During the progress of the first and second operations, the multiple first coil ends and the multiple second coil ends pass each other in sequence. The second coil end row is positioned radially outward from the stator core than the first coil end row. The aforementioned time difference is such that when the plurality of first coil ends and the plurality of second coil ends first pass each other, peeling of the coatings of the plurality of first coil ends and the plurality of second coil ends can be prevented, in a segment coil bending apparatus.
In the segment coil bending apparatus according to claim 7, The aforementioned time difference is set such that the rotation angle of the second coil end row in the circumferential direction, relative to the starting position of the second operation when the plurality of first coil ends and the plurality of second coil ends first pass each other, is 2.0° or more, in a segment coil bending apparatus.

Description

This invention relates to a method for bending segment coils and an apparatus for bending segment coils. In the manufacturing process of a stator, a bending process is performed to shape the coil ends of the segment coils inserted into the stator core into a predetermined shape. In this bending process, adjacent rows of coil ends, among multiple rows of coil ends arranged radially in the stator core, are twisted and bent in opposite directions in the circumferential direction. Patent documents 1 and 2 disclose techniques for preventing damage to the insulating coating of the segment coils due to contact between the coil ends of adjacent rows of coil ends as they pass each other during the bending process. Patent No. 3786059Patent No. 6798466 Figure 1 is a perspective view of a segment coil.Figure 2 is a perspective view of the stator core and multiple segment coils.Figure 3 is a schematic diagram of a bending apparatus according to an embodiment of the present invention.Figure 4 is a perspective view of multiple segment coils that have undergone twisting and bending.Figure 5 illustrates a method for bending segment coils.Figure 6 illustrates the time difference between the first and second actions.Figure 7 illustrates the contact between the bulging portions of the segment coils.Figure 8A illustrates the intersection of the first segment coil. Figure 8B illustrates the intersection of the fifth segment coil.Figure 9A shows an image of the ideal behavior of the coil end. Figure 9B shows an image of the actual behavior of the coil end when there is no time difference. Figure 9C shows an image of the actual behavior of the coil end when there is a time difference. As shown in Figure 1, the segment coil 10 has a roughly U-shape. The segment coil 10 has a conductor portion 12 and an insulating coating 14. The insulating coating 14 is, for example, enamel. The segment coil 10 has a pair of legs 16 and a turn portion 17. The pair of legs 16 are straight and extend parallel to each other. At the tip of each leg 16, there is a peeled portion 18 where the insulating coating 14 is peeled off, exposing the conductor portion 12. Hereinafter, the portion of the segment coil 10 with the insulating coating 14 is also referred to as the "covered portion 15". The turn portion 17 is the part of the segment coil 10 that connects the pair of legs 16. A meandering crank portion 20 is formed in the turn portion 17. As shown in Figure 2, the stator core 24 of the rotating electric machine has multiple slots 26. In the following description, the circumferential, axial, and radial directions of the stator core 24 may be simply referred to as "circumferential direction," "axial direction," and "radial direction," respectively. In the stator core 24, the multiple slots 26 are spaced apart in the circumferential direction. Multiple segment coils 10 are inserted into the multiple slots 26. In this case, a pair of legs 16 of the segment coils 10 are inserted into separate slots 26. As shown in Figure 3, with multiple segment coils 10 inserted into the stator core 24, a pair of legs 16 of each segment coil 10 protrude axially from the slot 26 of the stator core 24 (see also Figure 2). Hereinafter, the portion of each leg 16 that protrudes from the slot 26 will be referred to as the "coil end 28". Multiple segment coils 10 are arranged circumferentially around the stator core 24. Furthermore, multiple segment coils 10 are arranged radially around the stator core 24. Therefore, multiple coil ends 28 arranged circumferentially constitute a coil end row 28R. In the stator core 24, multiple coil end rows 28R are arranged radially. In this embodiment, eight coil end rows 28R are arranged radially. Hereafter, for the eight coil end rows 28R, the innermost coil end row 28R in the radial direction is designated as the 1st layer, and the outermost coil end row 28R in the radial direction is designated as the 8th layer. That is, from the inside to the outside in the radial direction, the coil end rows 28R from the 1st layer to the 8th layer are arranged in this order. A twisting and bending process (hereinafter simply referred to as "bending") is performed on the multiple segment coils 10 arranged in this manner. As shown in Figure 4, the bending process causes the radially adjacent coil end rows 28R to be twisted and bent in opposite directions in the circumferential direction. The twisted and bent coil ends 28 are joined together by appropriate means such as TIG welding at the tips (separated portions 18) of the corresponding coil ends 28. The bending of multiple segment coils 10 can be performed using the bending apparatus 30 shown in Figure 3. The bending apparatus 30 comprises a first station 30A and a second station (not shown). The first station 30A performs bending on the outer four layers (5th to 8th layers) of segment coils 10. The second station performs bending on the inner four layers (1st to 4th layers) of segment coils 10. The basic c