JPS6130504B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an armature of a commutator rotating electrical machine such as a DC machine or an AC commutator machine, and particularly relates to the arrangement of the armature coil.

In a DC machine with a large number of armature coil sides per armature slot, each coil in the armature winding has a different inductance, so the reactance voltage generated in the armature coil during commutation is In contrast, rectification compensation by interpolation cannot be achieved sufficiently. This increases the current shorted by the brushes, causing sparks and worsening commutation.

Conventional methods for preventing this have been to reduce the inductance of the armature coil and to suppress the short circuit current by increasing the resistance of the riser of the armature coil.

The former is a type in which a damper is provided in the slot in order to reduce the leakage inductance of the armature coil. Although this is effective as a preventive measure, since the damper is provided in the slot, the space of the armature conductor becomes poor, which becomes an obstacle when downsizing. Furthermore, since the damper must be provided separately, the number of parts increases and the cost becomes high.

The latter reduces the short-circuit current caused by the armature coil brush during rectification and can improve rectification, but it requires a separate riser resistor to improve rectification, so it requires a large number of parts like the former. It had the disadvantage of being expensive.

By the way, it is the armature coil that receives rectification last that suffers the most from rectification. The above will be explained in detail below with reference to the drawings.

FIG. 1 is an explanatory diagram showing a typical example in which the number of armature coil sides per slot is two. In this figure, 1 is a brush, 2 is a commutator, 3a, 3b
is a slot into which the armature coil 4 is inserted. The armature coils 4a, 4b are connected to the respective commutator pieces 2a, 2b, 2c of the commutator 2, and are rectified by the brush 1. In the state shown in Figure 1, brush 1
Therefore, both armature coils 4a and 4b are rectified. When the armature coil 4a rotates further from this state and the commutation of the armature coil 4a is completed, the armature coil 4b is short-circuited by the brush and acts to prevent changes in the flux linkage due to changes in the current of the armature coil 4a. The armature coil 4a has good commutation.
However, armature coil 4b ends rectification last.
As shown in FIG. 2, when commutation is finished, there is no armature coil 4 in the same slot 3a, 3b that prevents changes in interlinkage magnetic flux due to current changes, so the commutation of armature coil 4b deteriorates. , which will reduce the life of the brush.

The present invention has been made in view of this point, and its purpose is to eliminate the drawbacks of the prior art described above and to provide an armature for a current rotary electric machine that can perform good rectification without using accessories for improving rectification. It is on offer.

To achieve this objective, the invention is characterized in that the armature coil that is last commutated is placed in the upper part of the slot to reduce its leakage inductance.

An embodiment of the present invention will be described below with reference to FIG.

In Figure 3, 1 is a brush, 2 is a commutator, 3
A and 3b are slots into which the armature coil 4 is inserted. The armature coil 4a, which is connected to the commutator pieces 2a and 2b and receives commutation first, is wound at the lower part of the slots 3a and 3b where the leakage inductance becomes large.
The last armature coil 4 connected to the
b is slot 3 where the leakage inductance is small
It is wrapped around the tops of a and 3b.

When such an armature winding winding method is adopted, the inductance of the armature coil 4a that receives rectification first becomes large, and the inductance of the armature winding 4b that receives rectification last becomes small. When the commutation of the armature coil 4 is completed, the armature coil 4
Since the inductance of a is increased, the rectification seems to deteriorate, but the armature coil 4b
acts to prevent changes in the flux linkage due to changes in the current in the armature coil 4a, so the flow in the armature coil 4a does not deteriorate. On the other hand, since the inductance of the armature coil 4b, which is last to be rectified, is also reduced, good rectification can be obtained. Therefore, good rectification can be achieved without the need for special accessories such as dampers and riser resistors for improving rectification, and the device can be provided at low cost and the life of the brush can be extended.

In addition, although the said Example described the DC machine, this invention is not limited to this but can also be applied to an AC commutator machine.

As explained above, according to the present invention, it is possible to perform good rectification without using accessories for improving rectification, and it is possible to provide an armature for a commutator rotating electric machine that is inexpensive and has good rectification performance. .

[Brief explanation of the drawing]

1 and 2 are explanatory diagrams showing the armature coil position and commutation state in a conventional armature, and FIG. 3 is an explanatory diagram showing the armature coil position and commutation state in an armature according to an embodiment of the present invention. It is a diagram. 1... Brush, 2... Commutator, 3a, 3b...
Slot, 4a...Armature coil to be rectified first, 4b...Armature coil to be rectified last.

Claims (1)

[Claims] 1. An armature core having a large number of slots, an armature winding wound so that a plurality of coil sides per slot are housed in the slots of the motor core, and an armature winding coupled to the armature winding. In the armature of a commutator dynamo machine equipped with a commutator, the armature coil to be commutated last among the plurality of armature coils housed in the same slot is arranged at the top of the slot. The armature of a commutator rotating electric machine.