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.