| 摘要 |
PURPOSE:To obtain functions of high positioning accuracy with small size and high thrust by suitably varying the height between a rotor shaft of a movable element with a piezoelectric unit and the supporting surface in response to the moving mode of the element. CONSTITUTION:A linear pulse motor has a movable element 101, a stator 103 and a roller 106, generates an adhesive force between the element 101 and the stator 103 by a magnetic force based on the bias magnetic flux of a permanent magnet 51 to that the force becomes larger as the gap 105 is smaller. In this case, a plurality of laminated piezoelectric unit 209 is mounted between the roller shaft 107 of the element 101 and the roller shaft supporting surface 108 of the element 101, and the size of the gap 105 is varied by increasing or decreasing the applied voltage V to the unit 209. Thus, when the element 101 is moved, the gap 105 is reduced to obtain a large thrust, and the gap 105 is increased immediately before stopping to reduce the frictional force, thereby obtaining high stopping positional accuracy. |
