JPS5922465B2 - Flat armature with sandwich structure - Google Patents

Description

[Detailed Description of the Invention] A flat armature is a flat armature coil made by arranging one or more single coils made by winding an electric wire multiple times in a flat plate shape and molding or casting resin. This is what you get.

Due to the structure of the flat armature, the thrust direction becomes the magnetic path of the motor, and since it is iron-free, in order to improve the electrical characteristics of the motor, the thickness of the flat armature in the thrust direction should be made as thin as possible in advance. , and the distortion of the armature over time must be small.

When molding with resin an armature coil in which one or more single coils made of multiple turns of electric wire are arranged in a flat plate, conventionally the coil is exposed on the surface as shown in Figure 1, Or, after placing semi-cured impregnated glass cloth on both surfaces via armature coils as shown in Figure 2,
There is one in which a resin is molded so that the glass cloth covers the armature surface.

The armature shown in Figure 1 is not practical when applied to high-load or high-rpm motors because it is inferior to the armature with the configuration shown in Figure 2 in terms of mechanical strength, 8, and heat deterioration resistance. .

In the conventional armature shown in Fig. 2, the semi-cured resin-impregnated glass cloth is coated on the surface of the flat armature as described above. It has the effect of suppressing the mechanical strength of the armature and the deterioration of the wire coating.

However, in the armature shown in FIG. 2, the semi-cured resin-impregnated glass cloth must be made as thin as possible in order to reduce the thickness in the thrust direction, which forms the magnetic path.

Conventionally, glass cloth of less than 100μ has been used, but when making prepreg sheets by impregnating such thin glass cloth with semi-cured resin, there is a high possibility that the yarns will be bent, and When molding an armature using semi-hardened resin-impregnated glass cloth, the molding resin flows and fills the gaps created by the aligned coil groups, as shown by the arrows in Figure 3, so the flow of the molding resin is becomes uneven in the mold, thereby causing the glass cloth yarn to bend unevenly.

Furthermore, as shown in Figure 2, semi-cured resin-impregnated glass cloth was placed so as to cover both surfaces via the armature coil in order to provide uniformity to the internal stress of the armature. Mechanical strength of cured resin impregnated glass cloth,
Shrinkage during curing and thermal deterioration of semi-cured and semi-cured resins,
The internal stress caused by the cooling/heating cycle after curing had a directionality, and on both surfaces of the flat armature (here, it acted on the armature with completely uneven directionality).

For this reason, in the design of conventional flat armatures of this type, the most important consideration is the reliability of the armature, especially the change in dimensions of the armature over time, the stabilization of mechanical strength, and the reliability. It wasn't something that should have been done.

In FIGS. 1 to 3, 1 is an electric wire, 2 is a molded resin, 3 is a bearing, 4 is a commutator, 5 is a shaft, and 6 is a semi-cured resin-impregnated glass cloth.

The present invention eliminates these drawbacks and provides a flat armature that has excellent dimensional stability, mechanical strength, and high reliability, and also has the characteristics of improved heat deterioration resistance. be.

The structure of the present invention consists of a single coil made by winding an electric wire multiple times.
A flat armature coil is formed by arranging two or more flat armature coils, a semi-cured resin-impregnated sheet is placed on the surface of the armature coil with the flat armature coil interposed therebetween, and an integral rigid body is made of molded resin inside. In a flat armature having a sandwich structure of a resin-impregnated sheet and a molded resin, the above-mentioned conventional drawbacks are solved by using a non-directional glass non-woven fabric as the base material of the semi-cured resin-impregnated sheet. be.

The present invention will be described in detail below along with a conventional example.

Example 1 The thickness of the general ζ flat armature in the thrust direction, which becomes the magnetic path, is 1.0 to 3. The mechanical properties based on the conventional example shown in FIGS. 1 and 2 and the present invention will be explained using a plate-shaped model adjusted to have a thickness of 2 mm.

Each model consists of a molded resin only (Conventional Example 1), a sandwich-like model (conventional example 2) in which a semi-cured resin-impregnated glass cloth is arranged through a molded resin, and a model according to the present invention for the glass cloth base material. This is an example of the present invention in which a glass nonwoven fabric impregnated with a semi-cured resin is arranged as shown below.

However, the glass density of the glass base material here is glass cloth (plain weave) 20.69 / rri'' glass nonwoven fabric 13.8g
/m.

Further, the semi-cured resin 8 and the molding resin are the same.

First, the bending strength and tensile strength at room temperature (30°C) are as shown in Table 1.

However, in Table 1, A and B indicate the directionality of the strength of the glass cloth, and are shifted by 45 degrees from each other.

From Table 1, it can be seen that the mechanical strength of the present invention is increased by 20 to 30% compared to Conventional Example 1, and the semi-cured resin-impregnated sheet has no directionality and is dimensionally stable compared to Conventional Example 2. A product with uniform strength was obtained.

Example 2 When a single coil is arranged in a flat plate shape (arranged to form an armature coil and molded with molding resin), the thermal rigidity at that temperature will be reflected in the distortion during molding of the flat armature, so a coil with strong thermal rigidity is used. was desired.

This kind of effect of the present invention will be explained together with Conventional Examples 1 and 2.

Table 2 shows the bending strength in a high temperature atmosphere of each model adjusted to a thickness of 2 mm shown in Example 1.

As shown in Table 2, according to the present invention, compared to conventional example 1,
It can be seen that the effect on thermal rigidity is excellent in the range of 00 to 160°C.

Example 3 The effect of the semi-cured resin-impregnated sheet on the thermal deterioration life due to the bending strength of the molded resin can be explained using the model explained in Examples 1 and 2 as shown in Figure 4.6 As is clear from Figure 4. It can be seen that the flat armature shown in FIG. 1 having the structure of Example 1 has the poorest heat deterioration resistance, and the flat armature according to the present invention has the best heat deterioration resistance.

Example 4 A 54-segment flat armature coil was created by arranging single coils with 3 turns using self-fused wires of 0.65φ as shown in FIGS. 1 and 2 (Along with the conventional example, the present invention semi-cured resin-impregnated glass nonwoven fabric (glass density 11.5,
A flat armature (1.65 mm thick, 135 mm outer diameter) arranged in a sandwich shape through a flat armature coil and made integrally rigid with molded resin at 200°C.
Figure 5 shows the dimensional change over time when thermal deterioration occurs.

As is clear from FIG. 5, the flat armature according to the present invention has excellent effects in mechanical strength, thermal rigidity, heat deterioration resistance, dimensional stability, etc., and is extremely useful in the design and manufacture of flat armatures.

[Brief explanation of drawings]

Figure 1 is a perspective view of a conventional (conventional example 1) flat electric motor;
The figure is a perspective view of another conventional flat motor (conventional example 2), FIG. 3 is an explanatory diagram showing the flow of molding resin during manufacturing of the flat motor, and FIG. FIG. 5 is a characteristic diagram showing the bending life with respect to the deterioration temperature of the invention model. FIG. 5 is a characteristic diagram showing the dimensional change over time due to heating of the conventional example 1.2 and the invention model.

Claims (1)

[Claims] 1 By arranging a plurality of single coils made by winding electric wire multiple times into a flat plate shape to form a flat armature coil, coating the surface with a semi-cured resin impregnated sheet, and molding the coil into an integral rigid body, A flat armature having a sandwich structure having a coil wire integrated with molded resin on the inside and a resin-impregnated sheet on the outside, characterized in that a glass nonwoven fabric is used for the semi-cured resin-impregnated sheet substrate. Flat armature with sand inch structure.