Brush assembly for an electric motor

Patent metadata

Field	Value
Publication number	US-9711924-B2
Application number	US-201514689775-A
Country	US
Kind code	B2
Filing date	Apr 17, 2015
Priority date	Apr 18, 2014
Publication date	Jul 18, 2017
Grant date	Jul 18, 2017

Abstract

A brush assembly has a brush, a brush cage, and a spring. The spring is a constant force spring having two coil portions and a connecting portion. The connecting portion the brush are together received in the brush cage. The brush has a contact end arranged to make sliding contact with a commutator and a second end remote from the contact end against which the spring applies its force, to urge the brush out of the brush cage. A hook is formed at each of two opposite sides of the brush cage, at a first end portion of the brush cage adjacent the contact end of the brush. The coil portions respectively engage the hooks. The hooks extend at different angles to a corresponding outer surface of the brush cage.

First claim

The invention claimed is:

1. A brush assembly comprising a brush, a brush cage, and a spring,
wherein the spring comprises two coil portions and a connecting portion interconnecting the coil portions, the connecting portion of the spring and the brush being received in the brush cage,
the brush comprises a contact end and a second end remote from the contact end, the connecting portion of the spring abutting against the second end of the brush,
a hook is formed at each of two opposite sides of the brush cage, at a first end portion of the brush cage adjacent the contact end of the brush,
each of the two coil portions is connected with a corresponding one of the hooks, and
each of the hooks extends at a different angle to a corresponding outer surface of the brush cage,

wherein the hooks comprise a first hook and a second hook,
each of the hooks comprises a stop plate extending outwardly from the brush cage and a hook portion disposed at a distal end of the stop plate,
an angle A is formed between the stop plate of the first hook and the outer surface of the brush cage,
an angle B is formed between the stop plate of the second hook and the outer surface of the brush cage,
the angle A is not equal to the angle B, and
the angle A and the angle B are both greater than 90 degrees but less than 180 degrees.

2. The brush assembly of claim 1 , wherein the absolute value of a difference between the angle A and the angle B is greater than zero degree but less than 30 degrees.

3. The brush assembly of claim 1 , wherein the angle A is 120 degrees, and the angle B is 105 degrees.

4. The brush assembly of claim 1 , wherein the brush cage comprises two sidewalls, and each stop plate extends from a corresponding one of the sidewalls at the first end portion of the brush cage.

5. The brush assembly of claim 1 , wherein a cutout is formed between each stop plate and the corresponding hook portion.

6. The brush assembly of claim 1 , wherein the spring is a constant-force spring.

7. A motor comprising a stator and a rotor, the rotor comprising a commutator and a winding electrically connected with the commutator, wherein the motor further comprises the brush assembly of claim 1 , the contact end of the brush of the brush assembly making sliding contact with the commutator to supply power to the winding.

Assignees

• Johnson Electric Sa

Inventors

• Wei Hong Min
• Deng Yin
• Liu Bin
• Xing hui juan

Classifications

• H01R39/381 Primary

  characterised by the application of pressure to brush · CPC title