JP6855993B2 - Rotating machine stator - Google Patents

Description

The present invention relates to a stator of a rotary electric machine, and more particularly to an insulating sheet arranged in a slot so as to insulate a coil inserted into the slot of the stator core and the stator core.

Conventionally, a rotary electric machine including a stator in which a coil is wound and a rotor rotatably provided inside the stator is known. The coil of the stator is inserted and arranged in a plurality of slots formed at intervals in the circumferential direction on the inner peripheral portion of the tubular stator core. Then, an insulating sheet (for example, insulating paper) is interposed in the slot to electrically insulate the stator core and the coil.

In Patent Document 1, in a rotary electric machine stator in which an insulating paper for electrically insulating a stator core and a coil is arranged in a slot having an opening on the inward side in the radial direction, an end portion of the insulating paper is provided at a portion located at the opening of the slot. A structure in which each other is folded is disclosed (see FIG. 4 (a) of Patent Document 1).

Japanese Unexamined Patent Publication No. 2013-9499

In recent years, in order to reduce the size of a rotary electric machine, the gap between the stator and the rotor provided inside the stator has become narrower, and the coil of the stator and the rotor are arranged close to each other. Further, when the coil is arranged in the slot having the opening on the inner side in the radial direction, only the insulating sheet is interposed between the coil and the rotor. In the case of a structure in which the coil and the rotor are close to each other and only the insulating sheet is interposed between them, vortex loss may occur on the surface of the coil.

If the structure is such that the ends of the insulating sheets are folded over the portion located at the opening of the slot like the stator of the rotary electric machine disclosed in Patent Document 1, the thickness of the folded insulating sheets (two sheets of insulating paper). Since the distance between the coil and the rotor is increased by the amount of the thickness), the occurrence of vortex loss in the coil may be suppressed.

However, when the folded portion between the ends of the insulating sheets is arranged so as to be located on the inner wall surface on the outer side in the radial direction of the slot, one insulating sheet is provided at the portion located at the opening of the slot. As a result, the distance between the coil and the rotor becomes short, and there is a risk that vortex loss will occur in the coil.

Therefore, the present invention is to suppress the occurrence of vortex loss in the coil in the stator of a rotary electric machine in which an insulating sheet is arranged in a slot.

The stator of the rotary electric machine of the present invention is formed between an annular yoke, a plurality of teeth formed on the inner peripheral surface of the yoke at intervals in the circumferential direction, and an opening inward in the radial direction. A stator of a rotary electric machine including a stator core having a slot having a slot, a coil inserted into the slot, and an insulating sheet arranged in the slot to insulate the stator core and the coil. Both sides of the sheet are folded from the opening toward the back wall, and a magnetic shield material is arranged in a portion located at the opening, and the magnetic shield material is a portion located at the opening of the insulating sheet. Both sides of the insulating sheet extend to the back wall, and both ends of the side surfaces of the insulating sheet are folded toward each other at the back wall. ..

According to the stator of the rotary electric machine of the present invention, since the magnetic shield material is arranged in the portion of the insulating sheet located at the opening of the slot, it is possible to suppress the occurrence of vortex loss in the coil.

It is sectional drawing in the axial direction of a rotary electric machine. It is sectional drawing of the stator core in line AA shown in FIG. It is an enlarged view of one slot in FIG. It is a figure which shows the process procedure of arranging an insulating sheet in a slot.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is an axial sectional view of the rotary electric machine 10 of the present embodiment. As shown in FIG. 1, the rotary electric machine 10 is provided between a rotor 14 fixed to a rotary shaft 12 rotatably provided around a rotation center axis X and a gap around the rotor 14. It includes an annular stator 16.

The rotor 14 has a rotor core 18 formed by laminating a plurality of electromagnetic steel plates, and a plurality of rotor cores 18 formed on the outer peripheral edge side of the rotor core 18 and inserted into permanent magnet insertion holes 20 extending in the X direction of the rotation center axis. It includes a permanent magnet 22 and an end plate 24 that sandwiches the rotor core 18 from both sides in the axial direction. The permanent magnet 22 is fixed in the permanent magnet insertion hole 20 by the resin 26.

The stator 16 includes a tubular stator core 28 formed so as to surround the rotor 14, and a coil 30 mounted on the stator core 28. A cylindrical case 32 is fixed to the outer peripheral surface of the stator core 28 by a fixing method such as shrink fitting.

FIG. 2 is a cross-sectional view of the stator core 28 in line AA shown in FIG. As shown in FIG. 2, the stator core 28 protrudes inward in the radial direction from the inner peripheral surface of the annular yoke 34 extending in the circumferential direction of the stator core 28 and the inner peripheral surface of the yoke 34 toward the rotor 14, and is spaced apart in the circumferential direction. It is provided with a tooth 36 provided in the above direction. Slots 38 are formed between the teeth 36. The slots 38 also extend in the radial direction of the stator core 28 and are formed at intervals in the circumferential direction.

FIG. 3 is an enlarged cross-sectional view showing one slot 38 in FIG. The slot 38 is open toward the inner peripheral surface of the stator core 28.

The teeth 36 are formed on a main body portion 42 that protrudes from the inner peripheral surface of the yoke in the radial direction of the stator core 28 and a radial inner side end portion of the main body portion 42, and extends in the circumferential direction of the stator core 28. It has protrusions 44 and 45.

The inner surface of the slot 38 includes a rear wall surface 381 (back wall surface) located on the outermost side in the radial direction, a side wall surface 382,383 defined by the side surface of the main body 42 of the teeth 36, and a front wall surface 384,385. It has. Here, the front wall surface 384 is defined by the back surface of the overhanging portion 44, and the front wall surface 385 is defined by the back surface of the overhanging portion 45.

In the slot 38 formed in this way, the insulating sheet 50 is arranged along the inner surface of the slot 38. The insulating sheet 50 is an insulating member for electrically insulating the coil 30 inserted into the slot 38 and the stator core 28, and is, for example, insulating paper. In the present embodiment, the magnetic shield material 52 is immersed and coated on a part of the insulating sheet 50.

Here, a process procedure for arranging the insulating sheet 50 in the slot 38 of the stator core 28 will be described. FIG. 4 is a diagram showing a process procedure for arranging the insulating sheet 50 in the slot 38. Hereinafter, FIGS. 4A to 4D are simply referred to as (A) to (D). As shown in (A), first, the insulating sheet 50 is wound in a roll shape. The insulating sheet 50 is pulled out by a predetermined length and cut at the position of the broken line shown in (A), for example. As shown in (A), the insulating sheet 50 is coated with the magnetic shielding material 52 at a substantially central position along the direction in which the insulating sheet 50 is pulled out with a desired width. In (B), a state in which the insulating sheet 50 cut out in (A) is rotated by 90 degrees is shown. Next, the insulating sheet 50 is folded into a mountain at the position of the broken line shown in (B). As a result, as shown in (C), the insulating sheet 50 becomes substantially square (cylindrical). As a result, a front short side coated with the magnetic shield material 52 and a rear short side facing the front short side and where the folded portion 54 of the end portion of the insulating sheet 50 is located are formed. Then, as shown in (D), the front short side of the substantially square-shaped insulating sheet 50 is closer to the opening 40 side of the slot 38, and the rear short side of the insulating sheet 50 is in the radial direction of the slot 38. The insulating sheet 50 is inserted into the slot 38 so as to be on the outer wall surface (back wall surface) side.

By inserting the insulating sheet 50 into the slot 38 in this way, as shown in FIG. 3, the front side of the insulating sheet 50 to which the magnetic shielding material 52 is applied is applied along the front wall surfaces 384 and 385 of the slot 38. The short sides are arranged. That is, the insulating sheet 50 coated with the magnetic shield material 52 is arranged in the portion located at the opening 40. Further, the rear short side, which is the folded portion 54 of the end portion of the insulating sheet 50, is arranged along the rear wall surface 381 (back wall surface) of the slot 38, and is insulated along each of the side wall surfaces 382 and 383 of the slot 38. The long sides of each of the sheets 50 are arranged.

The coil 30 is inserted inside the insulating sheet 50 thus arranged in the slot 38. The coil 30 is arranged in a state of being insulated from the stator core 28 by winding an insulating sheet 50 around the coil 30. The coil 30 is composed of coil conductors 31 made of flat wires having a substantially quadrangular cross section, and a plurality of coil conductors 31 (six in this embodiment) are arranged in a row in one slot 38. The coil lead wire 31 is configured by insulatingly coating the core material formed of, for example, copper or the like with an insulating resin such as enamel. The coil conductor 31 is, for example, a conductor segment formed by bending in a substantially U shape, and two legs of the conductor segment are inserted into two slots 38 adjacent to or separated from each other in the circumferential direction, and the stator core 28 is inserted. The leg portion of the conductor segment protruding outward in the axial direction is bent and connected to another conductor segment adjacent in the circumferential direction or the radial direction by welding or the like.

In the stator of the rotary electric machine of the present embodiment described above, the magnetic shield material 52 is arranged in the portion of the insulating sheet 50 located at the opening 40 of the slot 38. Therefore, even if the rotor and the coil 30 are arranged close to each other, it is possible to suppress the occurrence of vortex loss in the coil 30. Thereby, the performance of the rotary electric machine 10 can be improved. In particular, when the rotor and the coil 30 are arranged close to each other, vortex loss is likely to occur on the surface of the coil lead wire 31 on the innermost side in the radial direction, but according to the present embodiment, this can be suppressed. it can.

Further, according to the stator of the rotary electric machine of the present embodiment described above, the magnetic shield material 52 can suppress the occurrence of vortex loss in the coil 30, so that the rotor and the coil 30 can be further brought closer to each other. That is, it is possible to shorten the radial length of the stator core 28 and narrow the gap between the stator and the rotor, and it is possible to reduce the size of the rotary electric machine 10.

In all the slots 38 of the stator core 28, it is not necessary to arrange the magnetic shield material 52 in the portion located at the opening 40 of the slot 38, and the magnetic shield material 52 of the present embodiment is used in some of the slots 38. It is also possible to arrange the coil 30 and arrange the coil in the other slot 38 by taking other measures against eddy damage.

In the stator 16 of the rotary electric machine of the embodiment described above, the magnetic shield material 52 is immersed and coated on the insulating sheet 50. However, the magnetic shield material 52 may not be applied to the insulating sheet 50, and a separate magnetic shield material may be arranged in a portion located at the opening 40 of the slot 38. For example, a separate magnetic shield material is arranged between them and the insulating sheet 50 along the front wall surfaces 384 and 385 of the slot 38. Alternatively, for example, a separate magnetic shield material is arranged between the surface of the coil lead wire 31 on the innermost side in the radial direction on the opening 40 side and the insulating sheet 50. Even in this way, the occurrence of vortex loss in the coil 30 can be suppressed.

10 rotary electric machine, 12 rotary shaft, 14 rotor, 16 stator, 18 rotor core, 20 permanent magnet insertion hole, 22 permanent magnet, 24 end plate, 26 resin, 28 stator core, 30 coil, 31 coil lead wire, 32 case, 34 yoke, 36 teeth, 38 slots, 40 openings, 42 main body, 44, 45 overhangs, 50 insulation sheet, 52 magnetic shield material, 54 folding parts, 381 rear wall surface (back wall surface), 382,383 side wall surface, 384, 385 Front wall surface, X rotation center axis.

Claims (1)

A stator core having an annular yoke, a plurality of teeth formed on the inner peripheral surface of the yoke at intervals in the circumferential direction, and a slot formed between the teeth and having an opening on the inward side in the radial direction. A stator of a rotary electric machine including a coil inserted into the slot and an insulating sheet arranged in the slot to insulate the stator core and the coil.
Both sides of the insulating sheet are folded from the opening toward the back wall, and a magnetic shield material is arranged at a portion located at the opening .
The magnetic shield material is applied to a portion of the insulating sheet located at the opening.
Both sides of the insulating sheet extend to the back wall, and both ends of the side of the insulating sheet are folded toward each other at the back wall.
A stator of a rotary electric machine characterized by this.

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