| 摘要 |
PROBLEM TO BE SOLVED: To accurately detect rotation by reducing the influence of load change.SOLUTION: A rotation detection circuit detects an induction current Ik flowing in the drive coil of a stepping motor 107 in a detection section T separated into a plurality of sections T1 to T3. The rotation detection circuit detects the rotation state of the stepping motor 107 on the basis of a pattern indicating whether a dielectric current Ik exceeding a predetermined reference value has been detected in each of the sections T1 to T3. A control section selects drive pulses P10 to P1 m, P2, corresponding to a rotation state detected by the rotation detection part, and rotationally drives the stepping motor 107 by supplying drive current i to the drive coil. Additionally, based on whether a plurality of dielectric current Ik exceeding a plurality of reference values have been detected in a first section T1, the rotation detection part selects the direction in which the dielectric current Ik is detected in sections T2, T3 after the first section T1, and detects the rotation state of the stepping motor 107 by a pattern based on the dielectric current Ik detected in each of the sections T1 to T3. |
