| 摘要 |
PURPOSE:To minimize positioning error of a head by selecting the phase or a combination of phases to be excited of a stepping motor when the head is positioned on each track so that the stationary angular error becomes minimum. CONSTITUTION:The magnitude of the angular error at each step of the stepping motor 3 differs defend up on the phase being excited. Thus the angular error at the respective excited states of the stepping motor 3 is measured and it is grasped from the results which of the angular stationary error for the phase A-phase and C-phase excited state and the phase B-phase and D-phase excited state is smaller, and, if the error for the phase A-phase and C-phase combination is lesser, an excitation phase changeover switch 16 is turned on. When the error for the phase B-phase and D-phase combination is lesser, it is turned off. In this manner, the positioning error for the head 21 is minimized. |
