JPH08237918A - Commutator motor - Google Patents

Abstract

PURPOSE: To eliminate the unbalanced magnetization owing to the armature magnetomotive force of respective armatures and also to prevent the generation of a spark in a commutating brush part. CONSTITUTION: A first armature 5 is disposed between first field pole pair 2a, 2b and a second armature 6 is disposed between second field pole pair 3a, 3b. Both armatures 5, 6 are electrified through respective commutating brushes 8a, 8b. The first field pole pair 2a, 2b and the second field pole pair 3a, 3b are disposed so that the magnetic field direction of both of them is made parallel. The armature winding 7 of the first armature 5 and the armature winding 7 of the second armature 6 are electrified so that the armature magnetomotive force of both armatures is cancelled out with each other. Since the armature magnetomotive force of both armatures 5, 6 is cancelled out, unbalanced magnetization is not generated in a main magnetic field produced by the respective field pole pairs 2a, 2b and 3a, 3b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a commutator motor having a pair of armatures.

[0002]

2. Description of the Related Art A commutator motor of this type has a first field pole pair and a second field pole pair installed in a casing, and
A first armature and a second armature are respectively arranged between these field pole pairs, and both armatures are rotated by energizing the respective armatures via rectifying brushes. There is.

Incidentally, this similar technique is disclosed in, for example, Japanese Patent Laid-Open No. 63-
No. 64552 is disclosed.

[0004]

However, in the above-mentioned conventional commutator motor, armature magnetomotive force is generated in each armature particularly when the commutator motor is operated under a high load condition, and the demagnetization due to the armature magnetomotive force is generated. It is conceivable that a spark may be generated due to a short circuit in the rectifying brush portion, causing deterioration of the rectifying brush and noise due to the spark.

Therefore, the present invention is intended to provide a commutator motor which can surely prevent generation of sparks in the commutation brush portion by eliminating the demagnetization due to the armature magnetomotive force of each armature.

[0006]

As a means for solving the above problems, the present invention provides a first armature and a second armature between at least a first field pole pair and at least a second field pole pair. Two armatures are respectively arranged, and the first armature and the second armature are energized via the commutation brushes respectively to rotate the two armatures. The armature windings of the armature and the second armature were energized so that the armature magnetomotive forces of both armatures would cancel each other.

[0007]

When the first armature and the second armature are energized,
Since the armature magnetomotive forces of both armatures act so as to cancel each other, the main magnetic field acting on each armature is not demagnetized.

[0008]

Embodiments of the present invention will now be described with reference to the drawings.

First, the first embodiment will be described with reference to FIGS.

In the drawings, 1 is an elliptic cylindrical yoke, and 2a, 2b, 3a and 3b are fixed to the inside of the yoke 1 by fitting, welding, bonding, screwing or the like. It is a field pole. Of these, the field poles 2a and 2b form the first field pole pair in the present invention, and the field poles 3a and 3b form the second field pole pair in the present invention. These field pole pairs 2a and 2
In the present embodiment, b and 3a, 3b are arranged side by side in the major axis direction of the yoke 1 so that the magnetic field directions formed by both pairs are parallel. Further, each field pole 2a, 2b, 3a, 3b is composed of an electromagnet having a field pole winding 4, and the field pole piece portion on the tip side thereof is formed in an arc shape.

Further, a first armature 5 and a second armature 6 are rotatably accommodated inside the yoke 1. The first armature 5 and the second armature 6 are arranged between the first field pole pair 2a, 2b and the second field pole pair 3a, 3b, and the respective armature windings are arranged. Line 7 is rectifying brush 8
It is connected to the power supply via a and 8b. The rectifying brushes 8a and 8b are fixedly mounted on the yoke 1 or a casing (not shown), and the tips of the rectifying brushes 8a and 8b come into sliding contact with the outer peripheral surface of the commutator 9 connected to each armature winding 7. There is.

A pair of rectifying brushes 8a, 8b corresponding to the first armature 5 and the second armature 6, respectively, are arranged on the same axis along the major axis direction of the yoke 1. At the position, each armature winding 7 of the first armature 5 and the second armature 6 is energized. The energization direction for each armature winding 4 is set so that the upper half sides of the rectifying brushes 8a and 8b are opposite to each other and the lower half sides thereof are opposite to each other, as shown in each of FIGS. 1 to 3. There is. Further, the axial lengths of the two armature windings 4, the number of turns, the energizing current value, etc. are set to be the same.

Due to the above-mentioned structure, as shown in FIG. 1, the field poles 2a and 3a are now set to the N pole and the field pole 2 is arranged.
The b and 3b sides are excited to the S poles respectively, and the first armature 5 and the second armature 5
If a current is applied to each armature winding 7 of the armature 6 in the direction shown in the figure, the first armature 5 rotates clockwise as indicated by arrow a, and the second armature 6 rotates counterclockwise as indicated by arrow b. At this time, if a load is applied to each armature 5, 6, each armature 5, 6
6, armature magnetomotive forces are generated, but these armature magnetomotive forces have the same magnitude as shown by arrows c and d in the figure, and are in directions facing each other, so that they are completely opposed to each other. They will cancel each other out. Therefore, the main magnetic field generated by the first field pole pair 2a, 2b and the second field pole pair 3a,
The main magnetic field generated by 3b is not demagnetized by the armature magnetomotive force, and therefore sparks or the like due to a short circuit do not occur in the rectifying brushes 8a and 8b.

When changing the rotating direction of each armature 5, 6, the energizing direction of each field pole winding 4 is changed without changing the energizing direction of each armature 5, 6 to the armature winding 7. By changing the field pole pairs 2a, 2b, 3
The exciting magnetic poles a and 3b may be changed. That is, for example, when changing the rotation direction of the second armature 6 from the state of FIG. 1 to the clockwise direction a, as shown in FIG. 2, excitation is performed so that the field pole 3b side becomes the N pole, On the contrary, the first
When the rotation direction of the armature 5 is changed to the counterclockwise direction b, it may be excited so that the field pole 2b side becomes the N pole as shown in FIG. In this way, each armature 5, 6
If the rotation direction of the armature is changed, the direction of the armature magnetomotive force of the armatures 5 and 6 does not change at all, and similarly sparks due to a short circuit can be reliably prevented. Furthermore, when changing the rotation speeds of the armatures 5 and 6, the number of turns of each field pole winding 4 and the value of the current flowing therethrough may be changed.

The embodiments of the present invention are not limited to those described above. For example, in the above embodiments,
The case where the directions of the armature magnetomotive force of the first armature 5 and the armature magnetomotive force of the second armature 6 are set to face each other has been described, but the setting is made so that both magnetomotive forces are in opposite directions. You may. Further, in the above embodiment, the field pole 2
Although the a and 3a and the field poles 2b and 3b are formed as separate bodies, if the field poles 2a and 3a, 2b and 3b are always excited to have the same polarity, as shown in FIG. The iron core 10a of 3a and the iron core 10b of the field poles 2b and 3b may be integrally formed. In such a case, the number of parts can be reduced, and both armatures 5 and 6 can be brought closer to each other, so that the overall size of the device can be reduced.

When actually using this commutator motor, as shown in FIG. 5, the output shafts 11a and 11b are projected from the same direction of the armatures 5 and 6, respectively, and these shafts 11a and 11b are projected. Power may be taken out separately from 11b, but as shown in FIG. 6, gears 12a and 12 that mesh with each other.
b to the output shafts 11a and 11b respectively,
The combined power of a and 11b may be taken out from the one shaft 11a. Further, as shown in FIG. 7, both output shafts 11a and 11b may be projected in the opposite directions from the respective armatures 5 and 6, and power may be taken out from the tip ends of these output shafts 11a and 11b, respectively.

Furthermore, in any of the above-described embodiments, the first field pole pair 2a, 2b and the second field pole pair 3a, 3b are constituted by electromagnets, which is shown in FIG. So that the two-field pole pairs 2a, 2b and 3a, 3b
May be constituted by a permanent magnet. In such a case, as is apparent from the figure, since it is not necessary to attach field pole windings to each magnetic pole, the number of parts can be reduced and the entire apparatus can be downsized. A plurality of pairs of the first and second field poles may be provided. In short, when the first and second armatures are energized, the armature magnetomotive forces of both armatures may cancel each other.

[0018]

As described above, according to the present invention, each armature winding of the first armature and the second armature is energized so that the armature magnetomotive forces of both armatures cancel each other. Since the main magnetic field acting on the armature is prevented from being demagnetized, it is possible to reliably prevent the generation of sparks at each rectifying brush portion.

Further, according to the invention of claim 2, since the first and second field pole pairs are respectively constituted by electromagnets, the rotating direction and the rotating direction of each armature are changed by changing the energizing direction and the current value with respect to each field pole pair. The speed can be adjusted freely.

Further, according to the third aspect of the present invention, since the first and second field pole pairs are each formed of a permanent magnet, the number of parts can be reduced and the size of the entire apparatus can be reduced.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a sectional view showing the same embodiment.

FIG. 3 is a cross-sectional view showing the same embodiment.

FIG. 4 is a sectional view showing another embodiment of the present invention.

FIG. 5 is a partially cutaway perspective view showing an application example of the present invention.

FIG. 6 is a partially cutaway perspective view showing another application example of the present invention.

FIG. 7 is a partially cutaway perspective view showing another application example of the present invention.

FIG. 8 is a sectional view showing another embodiment of the present invention.

[Explanation of symbols]

 2a, 2b ... 1st field pole winding, 3a, 3b ... 2nd field pole winding, 5 ... 1st armature, 6 ... 2nd armature, 7 ... Armature winding, 8a, 8b ... rectifying brush ...

Claims (3)

[Claims] 1. A first armature and a second armature are respectively arranged between at least one pair of first field pole pairs and at least one pair of second field pole pairs. In a commutator motor that rotates both armatures by energizing the armature and the second armature via respective commutation brushes, the armature windings of the first armature and the second armature are connected to each armature winding. A commutator motor, wherein the armature magnetomotive forces of both armatures are energized so as to cancel each other. 2. The commutator motor according to claim 1, wherein each of the first and second field pole pairs is composed of an electromagnet. 3. The commutator motor according to claim 1, wherein each of the first and second field pole pairs is composed of a permanent magnet.