Patent attributes
A linear oscillator and an electric toothbrush capable of emitting a low noise and of being assembled compact are provided. The linear oscillator, which reciprocates a shaft in an axial direction thereof, includes a plunger movable together with the shaft in the axial direction of the shaft, an elastic member for applying an axially acting 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 supplied thereto, and a fixing member restricting rotation of the plunger about an axis thereof within a predetermined angle. The electric toothbrush includes the linear oscillator and a brush head attached to the shaft for use in brushing teeth.