JPH0454854A - Dc motor - Google Patents

Abstract

PURPOSE:To easily change rated voltage without changing a shape in each part of an armature by providing an idle slot, where no coil is fitted, and paired short-circuited segments, which short-circuit two commutator segments, in an equal quantity. CONSTITUTION:An armature 1 is constituted of slots 110 to 124 of an almost cylindrical iron core 5 fitted to a rotary shaft 3, coils 7a to 7j, commutator 9, etc. The coils 7a to 7j are fitted to the ten slots 110 to 119 of the total 15 slots 110 to 124, and no coil is fitted to the rest of the slots to provide the idle slots 120 to 124. The commutator 9 has 15 commutator segments, and the commutator segment numbers 10 by electrically connecting the fellow segments in every third place. When, the number of the coils is decreased, the rated voltage is decreased, but a current conduction amount is increased by the decrease of the number of the coils to increase torque. An output characteristic is not changed because a rotational speed is not changed.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a DC motor equipped with a rotating armature.

[Prior Art] Conventionally, in DC motors, generally, a coil shaped like a pine needle is fitted into a slot provided in an iron core, and two terminals of the coil are connected to adjacent commutator segments. An armature is used in which the winding structure is connected to form a pattern winding structure, or the armature is connected to two commutator segments whose arrangement angles differ by 180 degrees to form a wave winding structure.
(For example, Daijitsu Publication No. 62-129282) In this type of DC motor, (number of revolutions N, [rpm]
is proportional to the power supply voltage V [V] and the torque T [kgf, c
m] has the characteristic that it is proportional to the supply current 1 [A], so if the power supply voltage (rated voltage) is changed, the output characteristics are the same as before the change (the output at the same rotation speed and torque at the rated voltage) P [KW] (=N-T-k, k is a predetermined constant)), it is necessary to change the number of turns of the armature winding. Since a multi-turn coil is used for the armature winding, by changing the number of turns in the coil, the rated voltage can be changed without changing the output characteristics.

[Problem to be solved by the invention] However, most DC motors for medium-sized machines and above use rectangular copper strips formed into one-turn coils, and the number of returns cannot be changed, so the output In order to change the rated voltage without changing the characteristics, it is necessary to change the coil shape, the number of slots and commutator segments, and to do so, the core is punched (core sheet) and the coil molding mold (home coil). and the shape of the commutator must be changed,
In the end, the entire armature had to be made anew.

SUMMARY OF THE INVENTION Therefore, the present invention has been made with the object of providing a DC motor in which the rated voltage can be easily changed without changing the shape of each part of the armature.

[Means for Solving the Problems] That is, the gist of the present invention (an iron core fitted into an upper rotating shaft and provided with a plurality of slots;
- A DC motor comprising an armature comprising a coil fitted into the plurality of slots and a commutator having the same number of commutator segments as the plurality of slots, wherein at least one slot among the plurality of slots is The direct current motor is characterized in that the above-mentioned idle slots are provided with no coils fitted therein, and the same number of short-circuit segment pairs as the above-mentioned idle slots are provided in which any two commutator segments of the commutator are short-circuited.

[Function] According to the DC motor of the present invention configured as above,
Since idle slots are provided and the same number of short-circuit segment pairs as idle slots are provided,
As the number of coils is reduced, the number of electrical commutator segments is also reduced, and there is no play in the connections between the coils and the commutator segments. In a DC motor using an armature with play slots and a commutator, the number of coils is reduced ((
Even if the rated voltage is lowered by (number of idle slots) / (total number of slots), the rotation speed will remain the same as the rotation speed (at its rated voltage) of a DC motor using an armature with coils fitted in all slots. At the same time, as the number of coils decreases, the amount of current increases and the torque increases, so the output characteristics do not change.

[Example] Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an explanatory diagram showing the structure of an armature of a DC motor to which the present invention is applied. FIG. 2 is an explanatory diagram showing the appearance of the armature.

As shown in the figure, an armature 11, a substantially cylindrical iron core 5 fitted to a rotating shaft 3, and 10 slots 110 to 11 of slots 110 to 124 bored on the outer peripheral surface of the iron core 5.
9, and a commutator 9 fitted to the rotating shaft 3 on the side of one end surface 5a of the iron core 5. It constitutes the main part of.

The slots 110 to 124 are grooves t, and the grooves have a U-shaped cross section and are bored in the axial direction at equal intervals on the outer peripheral surface of the iron core 5, and the total number of grooves is 15, of which 10 slots 110 to 119 have coils 78 to 7j. The remaining slots are not fitted into idle slots 120 to 124, and one idle slot 120 to 124 is arranged every second coil insertion slot 110 to 1.

Coils 78-7'' (one-turn coils made by molding copper strips into the shape of pine needles, and are fitted in each slot 110-1]9 in a double-layered state. In other words, the coils are wound clockwise. Sequentially, one coil side of the coils 7a to 7j is inserted into the bottom side of the slot (even tillO) and the tag is inserted into the fourth slot clockwise from the slot (110) (counting including the idle slot. For example, 112), the other coil side is fitted into the opening side.

The commutator 9 consists of ten commutator segments SO to S9, each of which is provided with one or two riser grooves RO to R14 (15 in total). One terminal and the other terminal of the upper coils 7a to 7 are respectively connected to the two adjacent riser grooves RO to R14, and each coil 78 to 7j is connected by lap winding (for example, One terminal of the melon coil 7a is connected to the riser groove R1, and the other terminal is connected to the riser groove R2).

This commutator 9 (, t) is a machined commutator with 75 commutator segments and each commutator segment is provided with one riser groove. That is, between the commutator segments The number of commutator segments is reduced to 10 by removing every second mica insulating piece m that is arranged and insulating the commutator segments and electrically connecting adjacent commutator segments. be.

DC electric motor g with armature 1 configured as above! 1
1. t DC motor with an armature that has coils fitted into all slots 110 to 124 and a commutator consisting of 15 commutator segments (even if 1fS rated voltage 48V)
The number of turns (the number of coils) of the armature winding is 2/3 compared to the above.

Therefore, even if the rated voltage is lowered to 2/3 (even if it is 1/36 V), the rotation speed will be the same as that of a DC motor with a rated voltage of 48 V (at a rated voltage of 48 V), and the amount of current will be 3/3
2 and the torque increases, so the output characteristics do not change.

Therefore, using the same body, coil, and commutator, it is possible to create a DC motor with a rated voltage of 48 V by fitting coils into all slots on one side, and with only one idle slot on the other side.
20 to 124 are provided to reduce the number of coils to 2/3 (from 15 to 10), and by removing some of the insulating mica m, the number of commutator segments is reduced to 2/3 (from 15 to 0). By doing so, a DC motor with a rated voltage of 2/3 (36V) can be manufactured, and the output characteristics can be made the same.

Therefore, the same armature parts (iron core, coil, commutator)
DC motors with different rated voltage specifications can be easily manufactured from the present invention, and there is no need to change the shapes of the core sheet, home coil, commutator, etc. according to the rated voltage specifications as in the past.

Here, in the present embodiment, part of the insulating mica m of the commutator 9 is removed to reduce the number of commutator segments to 10.
The insulating mica m may be left as is and some adjacent commutator segments may be electrically connected by shorting wires.

For example (as shown in FIG. 3, the commutator 15 has 15 commutator segments RO to R14,
The first two out of every three commutator segments RO to R141 are electrically connected by a shorting wire 30.

That is, as shown in FIG. 4, adjacent commutator segments SO, Sl, S3, S4, S6, and
, S9, 5IO1, S12, and S13 each riser groove 1: Insert the shorting wire 30 from the axial direction and fit it. This alone allows the number of commutator segments to be electrically reduced to ten.

In this embodiment, a DC motor with a permanent magnet field has been described, but the present invention can also be applied to a DC motor with an electromagnet field. In this case, by increasing or decreasing the number of turns of the first field winding according to the rated voltage, the same effects as in the above embodiment can be achieved.

[Effects of the Invention] As detailed above, according to the present invention, the number of coils can be reduced by the number of idle slots, and the number of short-circuit segment pairs is provided in the same number as the idle slots. Electrically the number of commutator segments can be reduced.

Therefore, the rated voltage of the DC motor can be easily changed without changing the output characteristics, and there is no need to change the shape of each part of the armature as in the conventional case.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram showing the structure of the armature of the DC motor of the example, Fig. 2 is an explanatory diagram showing the appearance of the armature, and Fig. 3 is an explanatory diagram showing the structure of the armature using a shorting wire. FIG. 4 is an explanatory diagram of the shorting line. 1... Armature 3... Rotating shaft 5... Iron core 7
a~7j...Coil 9...Commutator SO
~S9...Commutator segment RO~R14...Riser groove 110-119...Slot

Claims (1)

[Claims] An iron core fitted onto a rotating shaft and provided with a plurality of slots;
In a DC motor including an armature including a coil fitted into the plurality of slots and a commutator having the same number of commutator segments as the plurality of slots, at least one of the plurality of slots is A direct current motor characterized in that the slot has an idle slot in which a coil is not fitted, and the number of pairs of short-circuited segments in which any two commutator segments of the commutator are shorted are provided in the same number as the idle slot.