LINEAR ACTUATOR

PROBLEM TO BE SOLVED: To provide a linear actuator enabling excitations with high efficiency and enabling vibrations with superior responsiveness with respect to high frequency. SOLUTION: The linear actuator has a stator 10, juxtaposing two coils 16 and 18 along a central axis O and three teeth 12 to 14, forming a magnetic pole and a needle 20 which is fitted in a reciprocatingly movable manner, along the central axis O and holding a permanent magnet 23 by a pair of yokes 21 and 22 in the direction of the central axis O. The linear actuator further has two leaf springs 31 and 32, returning the mover 20 to the center position within a movable range during non-conduction of the coils 16 and 18, while ensuring an air gap C with the stator 10. The permanent magnet 23 is magnetized in the direction of the central axis O, and a length LM along the central axis O of the permanent magnet 23 is set in the length LT or smaller along the center axis O of the tooth 13, which forms a central magnetic pole for the stator 10. COPYRIGHT: (C)2010,JPO&INPIT