Patent ID: 7315098

Claim:
A linear oscillator for reciprocating a shaft in an axial direction of the shaft, comprising: a case; a plunger disposed in the case so as to be movable together with the shaft in the axial direction of the shaft; an elastic member acting in the axial direction of the shaft for applying a resilient force to the plunger; an electromagnetic driving unit operable to reciprocate the plunger in the axial direction of the shaft at a resonant frequency when an alternating current is applied thereto; the elastic member comprising a coil spring having first and second opposite ends, the first end being fixed with the case and the second end being fixed with the plunger to impart rotation to the shaft about the axis of the shaft within a predetermined angular range concurrently with an axial expansion or contraction of the coil spring caused by the reciprocation of the plunger.