| 摘要 |
<P>PROBLEM TO BE SOLVED: To inexpensively achieve rotation control for quickly responding with respect to fluctuations in rotation. <P>SOLUTION: A predetermined time Ts is counted repeatedly by five timer counters 1-5 for starting for counting with timings shifted by a predetermined time α (S112, S122, S133, S142, S152). Zero-crossing points are detected, based on an output signal from a position detecting circuit 103. The number of the detected zero-crossing points is counted repeatedly within a predetermined counting time Ts of the timer-counters 1-5; and each time the timer counters 1-5 finish counting the predetermined time Ts, switching timing for a drive pulse signal is calculated, based on the number of the zero-crossing points detected within the predetermined counting time Ts (S118, S128, S138, S148, S158). <P>COPYRIGHT: (C)2007,JPO&INPIT |
