| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a linear actuator which enables the stroke enlargement, the thrust increase, and the hysteresis lessening while keeping horizontal suction force properties. SOLUTION: In this linear actuator consisting of a needle and a stator, a pair of cylindrical rings (4) are counterposed to each other on the same axis with a certain vacant space from the peripheral face of the needle, and a pair of pole pieces (2) are arranged on the same axis on the side of both end faces of the needle with a certain vacant space from the peripheral face of the needle. Each of the permanent magnets (3) in a pair is interposed in each axial vacant space each made between each cylindrical ring and each pole piece. A drive coil (7) is wound on each peripheral face of the cylindrical rings in a pair, the pole pieces in a pair, and the permanent magnets in a pair. The permanent magnets in a pair are magnetized reversely in axial direction to each other. The peripheral face of each inner end of the pole piece in a pair is in shape of a taper having a thickness and an angle determined in advance.</p> |
