JPS6125336Y2 - - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a motor brush device.

As shown in Fig. 1, a conventional motor brush device is made of a band-shaped thin metal plate with a slit toy at its tip and a plurality of contact pieces, and the base of the brush is attached to an electrically insulating holding plate. The contact piece at the free end of the brush was pressed against the surface of the commutator plate.

However, such a conventional motor brush device has the disadvantage that the contact piece at the free end of the brush easily vibrates, and the height of the free end from the retaining plate varies.

The present invention was developed in view of these conventional drawbacks, and it reduces the variation in the height of the free end of the brush from the surface of the holding plate, and also creates a state in which the brush is in sliding contact with the surface of the commutator plate. The purpose is to suppress the vibration of the free end to a small level.

Hereinafter, the present invention will be explained based on the drawings of the embodiments.

Fig. 2 is a plan view of the brush block, Fig. 3 is a sectional view of the brush block of the brush device of the motor of the present invention, Fig. 4 is a plan view thereof, and Fig. 5 is a sectional view of the motor incorporating the brush block. , FIG. 6 is a sectional view of another embodiment of the present invention.

In the figure, 1 is a brush made by stamping a thin metal plate, such as a beryllium copper plate, into a belt shape, forming a plurality of slits 1a in the longitudinal direction in the center, and bending it into an arc shape. This is a disc-shaped holding plate in which both ends of the brush 1 are embedded. Thus, one base end of the brush 1 protrudes from the surface of the holding plate 2. In this way, a pair of brushes 1 are arranged in parallel and embedded in the holding plate 2 to constitute a brush block A. Therefore, the center portion of the brush 1 protrudes symmetrically in an arc shape from the surface of the holding plate 2.

The brush block A thus constructed is attached to the opening of the yoke B as shown in FIG. 5, and the outer surface of the central portion of the brush 1 is brought into pressure contact with the surface of the flat plate rotor C. In the pressed state, the brush 1 deforms as shown by the dotted line, and comes into pressure contact with the surface of the commutator plate 3 due to the elastic force required for the deformation.

As mentioned above, the brush device of the motor of this invention is
A brush block is constructed by embedding both ends of a band-shaped thin metal brush made of an elastic thin metal plate with a slit formed in the center and formed symmetrically with respect to the center in an electrically insulating holding plate. Since the brush block is attached to the opening of the yoke and the central part of the brush is in contact with the surface of the commutator plate of the flat plate rotor, the height of the central part does not vary from the surface of the holding plate.
The vibration that occurs when the center portion slides on the surface of the commutator plate of the flat plate rotor is small.

Further, since the central portion of the brush is formed in an arc shape approximately symmetrically with respect to the center, a stable sliding state can be maintained when the rotor rotates in both forward and reverse directions.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway sectional view of a brush device of a conventional motor, Fig. 2 is a plan view of the brush block, Fig. 3 is a sectional view of the brush block of the brush device of the motor of the present invention, and Fig. 4 is the same. FIG. 5 is a plan view, FIG. 5 is a sectional view of a motor incorporating a brush block, and FIG. 6 is a sectional view of another embodiment of the present invention. 1...Brush, 1a...Slit, 2...Holding plate, A...Brush block, B...Yoke, C...
Rotor, 3... Commutator plate.

Claims (1)

[Scope of utility model registration request] A brush block is constructed by forming a vertically long slit in the center and embedding both ends of the brush made of a strip-shaped thin metal plate vertically symmetrically with respect to the center in a holding plate, and inserting the brush block into the opening of the yoke. A brush device for a motor, characterized in that the brush is attached so that the central part of the brush comes into contact with the surface of a commutator plate of a flat plate rotor.