| 摘要 |
PROBLEM TO BE SOLVED: To make a smooth low-speed driving possible while keeping the quiet operation with a pulse having a frequency above the audible range by repeating the intermittent supply of a driving pulse wherein a driving pulse having the prescribed number of pulses is continuously supplied to an electromechanical transducing element and then the supply of this driving pulse is stopped for a given period of time. SOLUTION: At a low-speed driving, block pulse driving is conducted. To be more specific, a speed determining means 20 determines the number of continuous pulses in one block, a driven quantity of an actuator 10 in one block, and the pulse stop time, based on a requested speed. A quantity-of-movement controller 16 counts the number of driving pulses supplied to an actuator 10 by a driving pulse supplying means 12, and so controls that a driven quantity of the actuator 10 in one block may be a predetermined value. A stop controller 14 detects the termination of the supply of driving pulses for one blocks and then keeps the driving pulse supplying means 12 in a pulse supply stopping state until the passage of a given period of time wherein no pulse is supplied. |
