| 摘要 |
PURPOSE:To shorten the positioning time of a movable element by sequentially applying an exciting current having phases corresponding to a plurality of stable positions of the element when an exciting current is not applied. CONSTITUTION:When a start signal ST is inputted, a controller 40 sets a switch 39 to a pole positioning side. Then, the controller 40 sets the switch 39 to a pole positioning side. Then, the controller 40 sets a counted value corresponding to the position theta0=0 in a U/D counter 38 assuming that a movable element is first disposed at the position theta0=0. After storing as theta0=thetaOLD, the exciting current value tau0 at pole positioning time is applied to a movable element winding. After the prescribed time, the counted value of the counter 38 is inputted to thetaNEW, and the excitation is stopped. If thetaNEW>thetaOLD, the switch 39 is normally set to an operation side. If thetaNEW<=thetaOLD, the winding is again excited by assuming theta0=pi/2. |
