| 摘要 |
PURPOSE:To prevent a stepping motor from stepping out making an actuation frequency lower when a stop is driven in an open state than when the stop is driven except from the open position. CONSTITUTION:The number of stop stages is converted into the number of driving steps of the stepping motor by a clock circuit 32 and a distributing circuit 33. A stepping motor driver circuit 34 determines which of coils 12 and 13 is powered on according to said number of steps to rotate the stepping motor by an optional quantity. In such a case, the actuation frequency is made lower when the stop is driven in the open state than when the stop is driven except from the open position (Start pulse intervals are made long). Consequently, the stepping motor is prevented from stepping out. |
