Patent attributes
A small-sized and low-cost stepping motor includes a stator made of a soft magnetic material integrally having first and second outer magnetic poles, a first coil wound around a first bobbin externally fitted to the first outer magnetic pole, a second coil wound around a second bobbin externally fitted to the second outer magnetic pole, and a rotor part made of a soft magnetic material having a magnet fixed around a first column part by interference fit. The rotor part is rotatably supported by a first shaft part of a cover in a hole of the rotor part. An urging member made of a nonmagnetic material is rotatably fitted into the hole of the rotor part, and a compression coil spring urging the rotor part in the axial direction together with the urging member is disposed in the hole.