| 摘要 |
PURPOSE: To detect the absolute position of a rotor shaft of a DC motor and to drive the rotor shaft to a prescribed position according to a set value from the outside even when a power supply is cut off once erasing data within an apparatus. CONSTITUTION: A core for a transformer 19 is formed as a movable ring 22, and the ring 22 is formed of a first ring part whose permeability is low and of a second ring part whose permeability is high. The ring 22 is coupled to a rotor shaft for a DC motor 7 by means of a gear, and the ring is made movable when the rotor shaft is driven. |
