Commutator motor with brush biased toward initial contact side

A motor includes a rotor, a commutator, a brush, and a bias member. The commutator has a rectifying surface. The commutator rectifies an electric current supplied to the rotor through the rectifying surface. The rotor is rotated by being supplied with the electric current. The brush makes contact with the commutator via the rectifying surface. The rotor is supplied with the electric current through the brush. The brush starts making contact with the commutator on an entry side of the brush as the rotor and the commutator rotate with respect to the brush along a rotative direction and the commutator intermittently makes contact with the brush. The bias member biases the brush toward the entry side.