Patent attributes
A driving device which makes it possible to reduce the moment of inertia of a rotor and increase torque. A magnet is formed to have a hollow cylindrical shape and has magnetized sections which are magnetized to have alternately different poles in a circumferential direction thereof. A coil is wound coaxially with the magnet and is disposed in axially side-by-side relation to the magnet. A stator yoke is formed of a soft magnetic material and fixes the magnet and the coil. A rotor yoke is formed of a soft magnetic material, and has magnetic pole portions formed in opposed relation to the magnetized sections, for being magnetized by the coil. The rotor yoke is supported in a manner rotatable with respect to the stator yoke. An rotation restricting part limits a range of rotation of the rotor yoke within a predetermined angle.