JPH0516258B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to an armature for a rotating electric machine.

[Conventional technology]

FIG. 3 shows a cross-sectional view of an armature installed in a conventional DC machine, and FIG. 4 is an enlarged view of the armature core portion indicated by A in FIG. 3. In FIGS. 3 and 4, 1 is a DC generator, 2 is a yoke which is one of the fixed parts of the DC generator 1, and 3a to 4 are
It is a field pole that creates a magnetic flux fixed to the 3d yoke.
a and 3c are south poles, and 3b and 3d are north poles. The yoke 2 and the magnetic poles 3a to 3d form a stator. 4
5 is an armature mounted in the stator so as to be able to rotate at high speed, and 5 is a rotating shaft when the armature 4 rotates. 6a is a wide shallow groove slot formed on the outer circumferential side of the armature 4, and 6b is a narrow deep shallow groove slot formed radially inward from and connected to the wide shallow groove slot 6a. and the narrow deep groove slot 6b form one slot 6. Reference numeral 7 denotes a tooth portion existing between the slots, 8a and 8b are upper coils inserted into the wide shallow groove slot 6a, and 9a and 9b are lower coils inserted into the narrow deep groove slot 6b. 10 is a band of non-magnetic material, and upper end coils 8a, 8b inserted into the wide shallow groove slot 6a.
is wound around the outer periphery of the armature 4 to prevent it from flying out of the slot 6 due to the centrifugal force exerted by the high-speed rotation of the armature 4.

Next, the operation will be explained. Figure 5 shows field pole 3
In this figure, the arrows penetrating the field poles 3a to 3d and forming a loop are magnetic flux.

The armature 4 moves within the magnetic field generated in this way in the direction of arrow B.
When the armature rotates in the direction of , an electromotive force is generated in the upper coils 8a, 8b and the lower coils 9a, 9b inserted into the slot 6 formed around the armature 4 according to Fleming's left-hand rule, and the coils 8a, 8b,
Current flows through 9a and 9b. Direct current is obtained by rectifying this generated current.

In order to reduce the reactance voltage in the slot section that occurs during this rectification, the slot is shaped into an irregular slot consisting of one wide shallow slot 6a and one narrow deep slot 6b, as shown in Fig. 4. This is another conventional example, and the inductance of the slot section was reduced by about 40% compared to the inductance of the normally used rectangular slot section.

[Problem that the invention seeks to solve]

Since the conventional armature is configured as described above, when the magnetic flux applied in the radial direction from the field poles 3a to 3d concentrates on the tooth portion 7, the tooth portion 7 becomes magnetically saturated, and the upper mouth It passes through the coils 8a and 8b as interlinkage magnetic flux. This interlinkage magnetic flux generates eddy currents in the upper coils 8a and 8b, causing problems such as a significant increase in no-load loss and a significant temperature rise in the upper coils 8a and 8b.

This invention was made in order to eliminate the above-mentioned problems, and aims to provide an armature that can reduce the flux linkage passing through the armature coil and minimize the increase in inductance. purpose.

[Means for solving problems]

The armature of a rotating electric machine according to the present invention includes an armature core having a plurality of slots around the periphery, a width larger in the circumferential direction of the teeth existing between the slots, and a A magnetic bridge is arranged to cover a part of the slot.

[Effect]

In the armature of the rotating electric machine according to the present invention, the magnetic bridge prevents magnetic saturation of the teeth, thereby reducing flux linkage of the armature coil of the rotating electric machine and reducing no-load loss.

[Embodiments of the invention]

FIG. 1 shows a DC generator representing one embodiment of the present invention, and FIG. 2 is an enlarged view of the armature core portion indicated by C in FIG. 1. 1 to 10 are exactly the same as the above-mentioned conventional device. 11 has a width larger than the width in the circumferential direction of the teeth existing between the slots, and a wide shallow groove slot 8 is provided at the tip of the tooth 7.
This is a magnetic bridge placed so as to cover a part of a. The magnetic bridge 11 is fixed with a non-magnetic band 10 so as not to fly out of the armature due to the centrifugal force caused by the rotation of the armature core 4.

In the armature configured as described above, the magnetic flux directed from the field poles 3a to 3d toward the center of the armature core 4 passes through the magnetic bridge 11, and becomes an interlinkage magnetic flux to the upper coils 8a and 8b. decreases significantly. Therefore, the eddy current generated in the upper end coils 8a, 8b is significantly reduced, the increase in no-load loss can be reduced, and the temperature rise in the armature coil is reduced. Although the above embodiment deals with a DC generator, by arranging the magnetic bridge 11 at the tip of the toothed portion 7 so as to partially cover the slot, the DC motor can also have the same effect as in the case of a DC generator. No-load loss can be reduced. Furthermore, the same effect can be achieved even when this magnetic bridge 11 is attached not only to a DC machine but also to an induction machine or a synchronous machine.

Further, in the above embodiment, the magnetic bridge 11 placed at the tip of the tooth 7 is fixed with the non-magnetic band 10, but in order to fix it more firmly, a part of the tip of the tooth 7 has a convex part ( Alternatively, a recess (or a recess) may be provided in the magnetic bridge 11, and the two may be engaged and held. Also, magnetic bridge 11
However, the laminate structure can prevent eddy currents occurring within the bridge.

〔Effect of the invention〕

As explained above, the present invention includes an armature core having a plurality of slots around the periphery, a width larger than the width in the circumferential direction of the teeth existing between the slots, and an armature core having a width larger than the width in the circumferential direction of the teeth existing between the slots. By having a magnetic bridge placed so as to partially cover the part, it is possible to significantly reduce no-load loss without compromising the conventional rectifying ability, and it is effective to obtain an armature with high quality and reliability. .

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a DC generator showing one embodiment of the present invention, Fig. 2 is an enlarged view of the armature core shown in Fig. 1, and Fig. 3 is a sectional view of a conventional DC generator. , Figure 4 is an enlarged view of the conventional armature core, and Figure 5 is an enlarged view of the conventional armature core.
The figure is an explanatory diagram showing the state of the magnetic field generated by the magnetic poles. In the figure, 4 is an armature core, and 11 is a magnetic bridge. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Scope of Claims] 1. An armature core having a plurality of slots around the periphery, a width larger than the width in the circumferential direction of the teeth existing between the slots, and a part of the slot at the tip of the teeth. An armature for a rotating electric machine, comprising: a magnetic bridge disposed so as to cover the armature of the rotary electric machine. 2. Claim 1, characterized in that the slot has a deep groove narrow portion into which the lower coil is inserted, and a shallow groove wide portion above which the upper coil is inserted.
The armature of the rotating electrical machine described in Section 1. 3. The armature of a rotating electric machine according to claim 1, wherein the magnetic bridge has a laminate structure.