JPS608541Y2 - brush holder - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to the structure of a brush holder in a rotating electric machine.

Generally, in a brush holder for a rotating electric machine, brush holding pressure is usually obtained using a brush holding spring.

1 and 2 show the structure of a conventional brush holder, with FIG. 1 being a plan view and FIG. 2 being a side view.

In the figure, 1 is a brush, 2 is a brush presser spring, 3 is a brush presser foot, 4 is a spring winding shaft, 5 is a brush holding frame, 6, 7
is a cotter pin, and 8 and 9 are side plates. In this structure, the spring shaft 4 of the brush presser spring 2 using a spiral spring serves as a fulcrum to obtain brush presser pressure. Therefore, if the brush 1 is long, the brush presser foot 3
may come off from the head of the brush 1.

Also, the figure shows the case where the head of brush 1 is flat, but even if the head of brush 1 is round, if the brush becomes long, the brush 1
The direction in which the brush 1 is pushed changes greatly depending on the length of the brush, and the horizontal component force pushes the brush 1 from the side, which is undesirable as it causes damage to the brush.

For this reason, the distance between the brush 1 and the spring winding shaft 4 is kept as long as possible, and the design is such that the point and direction of pushing the head of the brush 1 do not change much. There is a problem in that the length of the brush that can be used and the shape of the brush head that can be used are limited due to variations in condition.

The present invention was developed in consideration of these points.
In order to keep the pushing point and direction of the head of the brush 1 as constant as possible, a suppression plate is used to suppress the brush holding position of the brush holding spring 2, and it takes up less space than conventional products for long brushes. The purpose is to obtain excellent brush presser pressure characteristics.

Hereinafter, the details of the present invention will be explained based on FIGS. 3 and 4.

FIG. 3 is a plan view showing an embodiment of the present invention, and FIG. 4 is a side view thereof.

Note that the same reference numerals as in FIGS. 1, 2, and 2 indicate equivalent parts.

As shown in the figure, the feature of the present invention is that it is provided with a plate 10 and its holding rod 11 for suppressing the brush holding position of the brush holding spring 2. The holding rod 11 is fixed to the brush holding frame 5 and is suppressed. One end of the plate 10 is rotatably supported by a holding rod 11, and the tip of a brush presser spring 2 is fixed to the other tip.

Further, the suppression plate 10 is gently curved upward to prevent the brush 1 from hitting the brush presser spring 2 when it becomes worn.

The brush holding spring 2 uses a spiral spring, and the distance between the spring winding shaft 4 and the brush holding fitting 3 can change within the range of the gap between the windings of the spring. uses materials whose rigidity does not change significantly.

Therefore, the holding rod 11 eventually becomes a fulcrum for the pressure exerted by the brush holding spring 2, and the brush holding point is restrained by the restraining plate 10 so as to lie on a circular arc centered on the holding rod 11.

Conventionally, the fulcrum of pressure by the brush presser spring 2 was the spring winding shaft 4.
However, since the holding rod 11 is provided farther from the brush than the spring winding shaft 4, the displacement of the brush head holding point due to a change in the length of the brush is extremely small compared to the conventional case.

Therefore, even when the brush 1 is long, the direction in which the brush presser spring 2 pushes the brush 1 does not change greatly depending on the length of the brush, and even when the head of the brush 1 is round, the direction in which the brush presser spring 2 pushes the brush 1 does not change greatly depending on the length of the brush. Since only the force acts and no horizontal component force is applied, there is no need to make the brush holding frame 5 particularly large, such as eliminating the possibility of brush breakage. You can gain the following advantages.

[Brief explanation of drawings]

Fig. 1 is a plan view showing the structure of a conventional general brush holder, Fig. 2 is a side view thereof, Fig. 3 is a plan view of a brush holder showing an embodiment of the present invention, and Fig. 4 is also a side view thereof. 1 is a brush, 2 is a brush holding spring, 3 is a brush holding fitting, 4 is a spring winding shaft, 5 is a brush holding frame, 6.7 is a cotter pin,
8 and 9 are side plates, 10 is a restraining plate, and 11 is a holding rod.

Claims (1)

[Scope of utility model registration request] In a brush holder that utilizes spring force in the circumferential direction around the spring axis of a spiral spring as brush presser pressure, a suppressing plate 10 having greater rigidity than the spring is installed near the tip of the brush presser part of the brush presser spring 2. One end of the suppressing plate 10 is fixed, and the other end of the suppressing plate 10 is rotatably attached to the brush holding frame 5 at a position on the brush presser spring 2 side seen from the brush 1 and further away from the spring winding shaft 5. brush holder.