JPS58201553A - Rotating electric machine stator - Google Patents

Abstract

PURPOSE:To improve the insulating performance of a stator for a rotary electric machine by forming the inner peripheral surface of the slot of a core in the minimum thickness required for insulation and integrally forming an insulating layer of the minimum thickness required for covering the edge of the core with the core, thereby increasing the coil containing amount. CONSTITUTION:The inner peripheral surface 1a of the slot of a core 1 and the outer peripheral surface 1c of the core as well as the upper and lower end surfaces 1b are covered with an integrally formed insulator 6 except the end of the toothed part of the core 1, and a coil 3 is wound, for example, on a yoke of the slot part of the core. The thickness of the insulator 6 which covers the core 1 is formed in the minimum value t1 required for insulation at the inner peripheral surface 1a of the slot and the outer peripheral surface 1c of the core, and in the sufficient value t2 durable against a force F applied to the edge of the core 1 by the coil 3 with the relationship of t1<t2. In this manner, the large amount of coil 3 can be contained in the slot so that the insulator 6 is not damaged at the edge of the core.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a stator core insulation structure for a rotating electric machine.

Generally, it is common knowledge that the stator core of a rotating electric machine is electrically insulated by various methods before windings are attached to it. In the case of a type in which the winding is inserted from slot to slot, the usual method is to insert a film 2 or the like along the inner surface of the slot of the core 1, as shown in Fig. 1. Since the insulating film 2 is long enough to stack the core 1 and is folded back on the outside of both ends of the slot, the inserted winding 3 can be installed without touching the edge 4 at the end of the core. It is. Here, the winding 3 is at least as long as the insulating film 2 than the normal insertion allowance length.
It is necessary to make the length that protrudes from the end face of the iron core 1 long. This is a molecular economy that does not perform any electrical work and requires a large amount of copper.

In order to improve this point, as shown in FIG. 2, an insulator 5 made of insulating resin is inserted from both end faces of the core to integrally cover the slot inner surface 1a and end face 1b of the core 1. It is used. According to this method, although the above problem is solved, the insulating film 2 of the slot
Compared to the case where the insertion work could be performed by a machine, mechanical insertion becomes difficult and manual insertion is required, resulting in poor workability.

Furthermore, considering the state in which the winding is inserted in the same way as in Figure 1,
The winding 3 may be pressed against the edge 4 of the iron core teeth by strong force during coil end shaping work. At that time, there is a risk that the insulator 5 at the edge portion may be cut or torn. Furthermore, since the insulators must be overlapped within the slot as shown in FIG. 3, the thickness increases and the effective winding space of the core slot, that is, the space factor, decreases, which is also undesirable.

On the other hand, the winding is attached to the yoke. In the case of a stator having so-called toroidal windings, the core insulation is done as shown in FIG. In this case, since the winding is wound around the yoke as shown in Figure 5, the only difference from the one in Figure 2 is that the insulator is formed 6' so as to cover the outer circumference 1C of the core. , there is basically no difference from the one in Figure 2.

Therefore, the problems mentioned in the explanation of FIG. 2 can be applied as is. Furthermore, in the case of this toroidal winding, unlike the former two in which the winding is wound on a winding form and then inserted into a slot, the winding is directly wound on the yoke, so the winding is performed as shown in Fig. 6. Due to the tension F in the wire, the insulation material at the edge portion 4' of the yoke is subjected to a large binding force, making it even more likely to break or tear than in the case described above.

The present invention aims to solve the above-mentioned problems all at once, and provide a stator core insulation structure with a simple structure and low cost that is stable and has excellent insulation properties even for various winding systems. .

FIG. 7 shows an example in which the present invention is applied to a stator having a toroidal winding shown in FIG. 5, and the present invention will be explained below using this as a representative example.

In FIG. 7, 1 is an iron core, and 6 is an insulator formed integrally with the iron core so as to cover the surface of the iron core, except for the tip of the teeth of the iron core. Thermoplastic molding resins that are commonly used as electrical insulating materials, such as polybutylene terephthalate (PET), polybutylene terephthalate (PBT), and polyacetal, are desirable. 3
is a winding wire that is wound around the yoke portion of the slot portion of the iron core from above the insulator, and only one slot portion is shown in the figure. Here, Fig. 8 shows the cross-sectional state of the tooth portion taken along the Y-Y' line, Fig. 9 shows the cross-sectional state of the yoke section taken along the z-z' line before winding, and further shows the z-z' line after winding. FIG. 10 shows the cross-sectional state of each.

Now, since the iron core 1 is integrally covered with the insulator 6, there are no cracks or seams on the iron core surface.
Of course, there are no holes like those seen with powder resin coatings, and a smooth insulating surface is formed. A unique feature of integral molding is that there is no change in wall thickness on the same surface due to overlapping insulators. Here, an insulator 6 covering the iron core 1
The thickness is adjusted to the minimum thickness tl required for insulation on the slot inner circumferential surface 1a and the core outer diameter surface 1C, while on the upper and lower end surfaces 1b of the iron core 1, the thickness of the core 1 is adjusted by the winding 3. A thickness t2 sufficient to withstand the force F applied to the edge portion is ensured. According to experiments, it is sufficient that tl has a thickness of 0.2 mm or more, while t2 is the wire diameter, although it depends on the stacking thickness of the core 1, the precision of each core, the flatness of the punched surface of the core, etc.
The width varies depending on the tension, the number of turns, etc., but a thickness of 0.5 mm or more is sufficient, and a thickness of 0.8 to 12 mm is most stable.

As explained above, the thickness of the insulator is changed between the slot inner circumferential surface and both end surfaces of the core, and the thickness of the slot inner circumferential surface is the minimum thickness required for insulation. By setting the necessary minimum thickness, more of the winding wire can be stored in the slot, and it is possible to prevent the edge cover strength from changing or breaking due to the tension and wire diameter during winding. In addition, since the insulator is integrally molded with the core inserted, there is no reduction in the windable area due to conventional overlapping on the inner peripheral surface of the slot.
Furthermore, the step of inserting an insulator can be omitted, improving productivity.

According to the present invention, as described above, all the drawbacks of the various conventional insulation structures are improved, more windings are stored in the slots, excess winding length is eliminated, and the insulation performance is improved. It is possible to obtain an insulation structure for a motor stator core that is improved and is also mass-producible.

The effect of the present invention is greatest in the case of a toroidal winding type stator in which wires are wound around the yoke part of the iron core.
A great effect can also be obtained in a stator of the type in which windings are inserted from slot to slot.

[Brief explanation of the drawing]

Figure 1 is a partial perspective view showing an example of a conventional stator insulation structure in which windings are inserted from slot to slot, and Figure 2 is a partial perspective view of an insulation structure in which molded insulators are inserted from both end faces of the core. , Fig. 3 is a sectional view taken along the line xx' in Fig. 2, Fig. 4 is a partial perspective view of the insulation structure of the stator to which toroidal winding is applied, and Fig. 5 is a toroidal winding to the stator shown in Fig. 4. FIG. 6 is a radial cross-sectional view of the winding portion of FIG. 6, and FIG. 7 is a partial perspective view of the toroidal winding according to the embodiment of the present invention. Figure 8 is Y- of Figure 7.
FIG. 9 is a sectional view taken along line Y', FIG. 9 is a sectional view taken along line zz' in FIG. 7, and FIG. 10 is a radial sectional view of the winding portion in FIG. 7. 1... Iron core, 6... Integrally molded insulator,
tl...Length of the slot inner circumferential surface and core outer circumferential surface of the insulator, t2/axis...Thickness of the upper and lower end surfaces of the core of the insulator. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 3 Figure 5 Figure 4 Figure 6! Figure 7 Figure 8 Figure 9

Claims (2)

[Claims] (1) An electrically insulating resin is applied to at least the winding mounting part of the stator core, which has an annular yoke part, a plurality of teeth protruding from the yoke part to the inner diameter side or the outer diameter side, and slots held between the teeth parts. A stator for a rotating electrical machine, in which an insulating layer is integrally formed, and the thickness of the insulating layer is made different between the inner circumferential surface of the slot and the upper and lower end surfaces of the iron core. (2) The rotary electric machine stator according to claim 1, wherein the insulating layer on both upper and lower end surfaces of the iron core is thicker than the insulating layer on the inner peripheral surface of the slot.