JP6936112B2 - Coil end molding method - Google Patents

Description

The present invention relates to a method for forming a coil end in which the lengths of the lead portions forming the coil end of the stator coil are different between adjacent coil ends.

Some motor stator coils use U-shaped segment coils. In this case, the ends of the segment coils are sequentially connected to form a coil. At this time, after the segment coils are aligned and inserted into the slots of the stator core, the open ends of the segment coils are sequentially connected, but those of which the segment coils adjacent in the radial direction are not connected must be reliably insulated from each other. For this purpose, an expansion process for widening the coil end spacing is performed.

This expansion process is performed by inserting a jig between the lead portions forming the coil end of the segment coil and bending the coil end in the radial direction. Here, the segment coil is basically covered with an insulating film, but the insulating film is removed from the lead portion (tip portion) connected to the other segment coil. Therefore, when bent in the radial direction, the coil end bent earlier may come into contact with the adjacent coil end, and the insulating film of the adjacent coil end may be damaged.

In Patent Document 1, the tip of an adjacent coil end on the rear side is held by a jig urged by a spring to limit the movement of the coil end and prevent damage to the insulating film of the coil end. suggest.

Japanese Unexamined Patent Publication No. 2016-131424

The configuration of Patent Document 1 can prevent damage to the insulating film of the coil end, but the structure of the jig is relatively complicated, and since a spring is used, the forming force (bending force) of the coil end is individual. There was a possibility that the bending accuracy would not be sufficient because it would be different at the coil end.

The coil end molding method according to the present invention is a coil end molding method in which the lengths of the lead portions forming the coil ends of the stator coil are different between adjacent coil ends, and is a portion for molding the lead portions. A first passage having a circumferential cam for tilting the coil end in the circumferential direction in front of the insertion direction, a radial cam for bending the coil end in the radial direction behind the insertion direction, and a coil in front of the insertion direction. A jig having a second passage that does not have a circumferential cam for tilting the end in the circumferential direction and has a radial cam for bending in the radial direction, and one of the adjacent lead portions is the first passage. By inserting the other into the coil end so that it enters the second passage, one of the adjacent lead portions is tilted in the circumferential direction to shift the circumferential position of both adjacent lead portions on the distal end side, and then adjacent to each other. It is characterized in that both lead portions are bent in the radial direction.

According to the present invention, when the lead portion is bent in the radial direction, the circumferential position of the adjacent lead portion on the tip end side is displaced, and it is possible to prevent the two from colliding with each other. Therefore, it is possible to prevent the insulating film of the long lead portion from being peeled off by the tip portion of the short lead portion.

It is a perspective view of the coil end in the conventional general stator core. It is a figure which shows the structure of the segment coil. It is a figure explaining the expansion process of a segment coil. It is a figure explaining the expansion process of the segment coil which concerns on embodiment. It is a perspective view which shows the structure of a jig. It is a top view which shows the structure of a jig. It is a figure explaining the circumferential bending of the lead part by a slope.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to the embodiments described herein.

<Constituent configuration>
FIG. 1 shows a schematic configuration of a conventional general stator 10. The stator 10 has a substantially cylindrical or annular-shaped stator core 12 and a coil 14 mounted so as to be wound around the inner peripheral side of the stator core 12. The stator core 12 includes a cylindrical or annular yoke 16 and a plurality of teeth 18 extending inward in the stator radial direction from the yoke 16. The plurality of teeth 18 are arranged at intervals along the circumferential direction of the stator, and the space between the adjacent teeth 18 is called a slot 20, and the coil 14 is wound around the teeth 18 by arranging the coil 14 in the slot 20. It is turned. The coil 14 is composed of, for example, a coil conductor 22 having a rectangular cross section, and the coil conductor 22 extends from a portion located in the slot 20 and the portion extending in the stator axis direction and projects from the end surface of the stator core 12 to form a coil end 24. Includes the part to be formed. The coil conductor 22 exiting one slot 20 extends into another slot 20 within the coil end 24 and enters that slot 20.

In the embodiment of the present invention, the coil 14 is formed on the stator core 12 shown in FIG. 1 by using the U-shaped segment coil 32 as shown in FIG. That is, the two legs of the segment coil 32 are each inserted into the slot 20, the lead portion 34 on the tip side of the two legs is projected from the stator core 12, and the lead portion 34 is bent in the circumferential direction to form another segment coil. The coil 14 is formed by connecting to the lead portion 34 of the 32. The connection between the segment coils 32 is usually performed by welding. The segment coil 32 is covered with an insulating film 32b as a whole, but the tip portion 32a of the lead portion 34, which is a connection portion between the segment coils 32, has the insulating film 32b removed, and the tip portion 32a is the other. It is connected to the tip end portion 32a of the lead portion 34 of the segment coil 32 of the above.

<Extended processing>
Here, it is necessary to prevent the connection portions between the segment coils 32 from coming into contact with other connection portions. For this purpose, an expansion process is performed in which the distance between the lead portions 34 of the adjacent segment coils 32 is widened.

FIG. 3A shows a state in which the segment coil 32 is inserted into the slot 20 of the stator core 12. In this case, the legs of the segment coil 32 remain straight, and a plurality of the legs are aligned in the radial direction. In this state, a jig having a wedge-shaped blade is inserted into the gap between the segment coils 32. As a result, as shown in FIG. 3B, the legs of the segment coil 32 move outward in the radial direction, so that the gap is expanded. In this example, two expansion processes are performed in relation to the other party to be connected.

Further, the moving distance of the lead portion 34 to the outside in the expansion process becomes larger toward the outer diameter side. Therefore, the amount of protrusion of the leg of the segment coil 32 (the length of the lead portion 34) before the expansion process is larger toward the outer diameter side. The outermost segment coil 32 may be connected to other wiring, for example, a power line, instead of being connected to another segment coil. In that case, the protrusion amount of the leg of the outermost segment coil 32 is inside. It is smaller than the segment coil 32.

FIG. 4 shows the procedure of the expansion process. As shown in FIG. 4A, the lead portion 34 of the segment coil 32 protrudes from the stator core 12. As shown in FIG. 4B, the blade 40 is lowered and inserted between the lead portions 34 of the segment coil 32. The tip of the blade 40 is tapered, and the outer diameter side thereof is located outside the inner diameter side of the segment coil 32 to be pushed away. Therefore, as the blade 40 descends, the segment coil 32 in contact with the blade 40 tilts outward. The clamp 42 holds the root portion of the inclined segment coil 32 near the stator core 12 from the outside to assist the molding of the segment coil 32.

Here, in the present embodiment, as shown in FIG. 4C, the legs of the segment coil 32 tilting in the radial direction are tilted in the circumferential direction. That is, by using the jig of FIG. 5 described later, the segment coil 32 is tilted in the circumferential direction before the segment coil 32 is tilted in the radial direction. In particular, this pressing movement in the circumferential direction is performed only on one of the adjacent segment coils 32. Therefore, as shown in FIG. 4C, when the segment coil 32 is tilted in the radial direction, the tips of the two adjacent segment coils 32 are displaced in the circumferential direction.

If there is no circumferential movement of the legs of the segment coil, the insulating film 32b of the longer segment coil 32 and the tip 32a of the shorter segment coil 32 come into contact and collide, and the insulating film 32b is destroyed. It may be peeled off. In the present embodiment, the insulating film 32b of the segment coil 32 can be protected by avoiding contact and collision.

<Jig>
FIG. 5 shows a perspective view of a configuration example of the jig 50 for simultaneously performing two types of expansion processing in the circumferential direction and the radial direction of the segment coil 32 as described above. Further, FIG. 6 shows a plan view thereof.

This example is a jig for pushing and bending six segment coils 32 at a time. The jig 50 divides the six segment coils 32 that fit into one slot 20 into three, and has cam bases 52a, 52b, and 52c for each of the two on the right side, the center, and the left side, respectively. These three cam bases move the segment coil 32 selected from the teeth 18 side adjacent to the six segment coils 32 inserted in the slot 20 in the circumferential direction and the radial direction. Since the three cam bases 52 have substantially the same configuration and operation, the movement of the segment coil 32 in the circumferential direction by the cam base 52a and the subsequent movement of the segment coil 32 in the radial direction will be described below.

The cam base 52a is provided with two passages for two adjacent segment coils 32 on the outer diameter side. One first passage 44 is provided with an ascending slope 44a in the circumferential direction as a circumferential cam, and the other second passage 46 is not provided with a slope and is flat. Therefore, only the segment coil 32 that moves in the first passage 44 moves in the circumferential direction by being guided by the ascending slope 44a. This structure is the same for the cam base on the center and left side.

A blade 40 is arranged as a radial cam behind the passages 44 and 46. The blade 40 is for moving the segment coil 32 in the radial direction, and when the segment coil 32 enters between the blades 40, the segment coil 32 moves in the radial direction.

Therefore, the segment coil 32 that enters the passage 44 is once tilted in the circumferential direction and then tilted in the radial direction to be formed. On the other hand, the segment coil 32 entering the passage 46 is formed by being tilted only in the radial direction without being tilted in the circumferential direction. As described above, the expansion processing by the cam base 52a is performed, and the expansion processing for the segment coil 32 is also performed in the other cam bases 52b and 52c in the same manner. In the embodiment, the three cam bases 52a, 52b, and 52c have different heights, but this corresponds to the fact that each segment coil 32 has a different height in the lead portion 34, and the jig It is desirable that the height of each cam stand 52 can be freely adjusted.

Therefore, by using this jig 50, as shown in FIG. 4, one segment coil 32 is once tilted in the circumferential direction, and the adjacent segment coils 32 are not tilted in the circumferential direction, and then both are diametered together. Can be tilted in a direction.

Although FIG. 5 shows the configuration of the jig 50 that tilts the segment coils 32 one by one, the segment coils 32 may be tilted together by two.

FIG. 7 shows bending of the segment coil 32 in the circumferential direction. The tip end side of the segment coil 32 rides on the ascending slope 44a and is guided here to be bent in the circumferential direction.

The tip portion 32a of the segment coil 32 is bent in the circumferential direction and then connected to the tip portion 32a of another lead portion 34. Therefore, it is advisable to perform bending for this connection by bending in the circumferential direction by the ascending slope 44a. At the very least, it is preferable to match the bending directions.

<Effect of embodiment>
According to the present embodiment, one of the adjacent lead portions 34 is bent in the circumferential direction before the lead portion 34 constituting the coil end is bent in the radial direction. Therefore, when the lead portion 34 is bent in the radial direction, the circumferential position of the adjacent lead portion 34 on the distal end side is displaced, and it is possible to prevent the two from colliding with each other. Therefore, it is possible to prevent the insulating film 32b of the long lead portion 34 from being peeled off by the tip portion 32a of the short lead portion.

By using a jig provided with a passage having a slope for bending in the circumferential direction and a passage having no slope, the bending process in the circumferential direction and the radial direction can be effectively performed.

10 stator, 12 stator core, 14 coil, 16 yoke, 18 teeth, 20 slot, 22 coil lead wire, 24 coil end, 32 segment coil, 32a tip, 32b insulation film, 34 reed, 40 blade, 42 clamp, 44, 46 passages, 44a uphill slopes, 50 jigs, 52 cam stands.

Claims (1)

This is a coil end molding method in which the length of the lead portion forming the coil end of the stator coil is different between adjacent coil ends.
A first portion for forming a lead portion, which has a circumferential cam for tilting the coil end in the circumferential direction in front of the insertion direction and a radial cam for bending the coil end in the radial direction behind the insertion direction. Adjacent leads to a jig having a passage and a second passage that does not have a circumferential cam for tilting the coil end circumferentially forward in the insertion direction but has a radial cam for bending in the radial direction. By inserting the part into the coil end so that one enters the first passage and the other enters the second passage.
After shifting the circumferential position of both adjacent reeds by tilting one of the adjacent reeds in the circumferential direction,
Bend both adjacent reeds in the radial direction,
How to mold the coil end.

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