| 摘要 |
<p>A linear actuator (1) is equipped with: a first magnet (23) comprising an electromagnet; a second magnet (24) comprising a permanent magnet or an electromagnet; a needle (22) which is attached to either the first magnet (23) or the second magnet (24), and moves to and from the other of the first magnet (23) and the second magnet (24) in a straight line; a control unit (30) for controlling the amount of current to be conducted to the first magnet (23) according to a current supply interval, and moving the needle (22) back and forth in a straight line; and a drive-amount detection unit (40) for reporting the drive amount of the needle (22) produced by the control unit (30), on the basis of one or more of the displacement of the needle (22), the speed at which the needle (22) moves back and forth, and the acceleration of the back and forth movement. The control unit (30) performs a feedback control for the current supply interval so as to cause the drive amount to approach a target value, on the basis of the difference between the drive amount and the target value for the drive amount, and switches the target value on the basis of changes in the current supply interval.</p> |
