JPS5845492Y2 - Small motor brush device - Google Patents

Description

[Detailed description of the invention] Generally, the brush device of a small motor has a thickness of, for example, 0.02 mm.
The structure is simplified by forming a spring plate of beryllium copper with a diameter of mm into a band shape, directly holding the brush, and using it as a contact pressure retainer and conductor.

Therefore, the applicant first formed a U-shaped portion 2 in cross section on the spring plate 1 as shown in FIGS. 1 to 3, and the U-shaped portion 2
A brush insertion hole 3 is provided in the spring plate ice plane 1a, and the hole 3
Upward pushing pieces 4, 4 are provided on opposite sides of the vertical part 5.
Insert the T-shaped brush 5 consisting of a horizontal part 5a and a horizontal part 5b into the brush insertion hole 3 so that the lower surface of the horizontal part 5b comes into contact with the push-up pieces 4, 4, and push the brush 5 with the push-up pieces 4, 4. A brush device has been proposed in which the upper surface of the brush 5 is engaged with engaging claws 7, 7 provided inwardly on the bent pieces 6, 6 on both sides of the spring plate.

This brush device can be applied regardless of the interstitial material of the brush.

It has the effect of simplifying parts processing, improving mass productivity, and reducing costs.

However, when the brush is assembled, the engaging claws 7, 7 pushed outward by the brush 5 cannot be elastically restored until the upper surface of the brush passes over them, as shown by the chain lines in FIGS.

Therefore, when the engaging claws 7, 7 are restored, a gap d is created between them and the upper surface of the brush.

Therefore, the brush 5 has its upper surface engaged with the engaging claws 7, 7.
In other words, it is pushed up by the push-up pieces 4, 4 by the gap d.

Therefore, the brush 5 is locally supported only by the push-up pieces 4, 4 and the engaging claws 7, 7, and is easily damaged.

Alternatively, the contact area between the spring plate 1 and the brush 5 is extremely small, and sufficient electrical continuity from the brush 5 to the spring plate 1 cannot be obtained.

Since the push-up pieces 4, 4 are provided on the spring plate 1, processing is troublesome and the mechanical strength of the spring plate is weakened.

This proposal does not provide a brush push-up piece on the spring plate 1,
However, when the engaging claws 7, 7 are restored, there is a gap d between them and the top surface of the brush.
The object of the present invention is to obtain a brush device that does not cause.

As a means for this purpose, as shown in FIGS. 4 to 7, the ridgeline portion of the brush horizontal portion 5b is chamfered to provide restoration guides 8, 8 for the engaging claws 7, 7.

Since the present invention has the above-mentioned configuration, the engaging claws 7, 7 are pushed outward by the side surfaces of the brush at the initial stage of brush assembly;
When the restoration guides 8.8 of the assembled brushes are opposed to each other, the brushes 8, 8 are immediately elastically restored by contacting the guides 8,8.

The contact position changes as the brush is assembled, and no gap is always created between the engaging claws 7, 7 and the upper surface of the brush.

Then, the engaging claws 7, 7 press the brush 5 downward via the guide 8.8 with their restoring elastic force, so that the horizontal lower surface of the brush 5 comes into pressure contact with the spring plate surface.

Therefore, the spring plate and the brush 5 come into pressure contact over a wide area, and the brush is less likely to be damaged and the electrical conductivity from the brush 5 to the spring plate 1 is stable.

Alternatively, since there is no need to provide the brush push-up pieces 4, 4 on the spring plate 1, the processing of the spring plate 1 is simplified, and the spring plate 1
It has the effect of not weakening the mechanical strength of ゜.

[Brief explanation of drawings]

Fig. 1 is an exploded perspective view of the spring plate and brush of a conventional brush device, Fig. 2 is a cross-sectional front view of its assembled state, Fig. 3 is a vertical cross-sectional side view, and Fig. 4 is a spring plate of the proposed brush device. FIG. 5 is a cross-sectional front view of the assembled brush, FIG. 6 is a plan view, and FIG. 7 is a vertical cross-sectional side view. 1 is a spring plate, 2 is a U-shaped part, 3 is a hole, 4, 4 are push-up pieces, 5 is a brush, 6, 6 are bent pieces, 7.7 is an engaging claw, 8, 8 is an engagement Nail restoration guide.

Claims (1)

[Scope of utility model registration request] A U-shaped cross section is formed at one end of the conductive spring plate that serves as both a conductor and a contact pressure retainer, and a brush insertion hole is provided in the spring plate ice plane of the U-shaped portion. An inward engaging claw is provided on the bent piece, the ridgeline of the horizontal part of a T-shaped brush consisting of a vertical part and a horizontal part is chamfered to provide a restoring guide for the engaging claw, and the vertical part of the T-shaped brush is A small motor brush device that is inserted into a brush insertion hole and has the above-mentioned engaging claw engaged with a restoring guide.