PURPOSE:To avoid collision of a movable plate against peripheral members even when there is a vibration of large amplitude from an engine caused by oscillation after cranking in concert with an engine start operation and an engine stop, by applying a control voltage to an electrode plate provided to a rattle element for a specified time after an ignition key is put on or off. CONSTITUTION:Reduction of vibration through thorough usage of an orifice function is performed by applying a control voltage to each of electrode members 44b, 52 in accordance with the number of rotation of an engine and the speed, for example, by locking a movable plate 42 inside a rattle element 40 by way of heightening the viscosity of an electric rheology fluid inside the rattle element 40 at the time of idling of the engine. Subsequently, when an ignition current is fed into the the primary side of an ignition coil at the time of starting of a car, the fluid comes to be in stick state by way of heightening the viscosity of the fluid inside the rattle element 40, the movable plate 42 stored in the rattle element 40 is locked, collision against its peripheral members is avoided and generation of hammering noise is prevented.
展开▼
