DYNAMIC DAMPER FOR VEHICLE

PURPOSE:To effectively suppress the resonnance of a vehicle whose resonant frequency is varied by mounting a spring member in which a free end is always connected to a mass body and a spring member in which a free end is connected to the mass body through a magnet so as to be attached and detached on the vehicle. CONSTITUTION:A dynamic damper A is comprised by mounting a spring member 2a in which a free end is always connected to a mass body 1 and a pair of spring members 2b in which a free end is connected to the mass body 1 through a magnet 3 so as to be attached and detached on places where the vibration control of a vehicle is required. In addition, the magnet 3 is switched to either excitation or non-excitation state by using a magnet driver 7 and is set under the on-off control of a controller 9 that controls the magnet driver 7 according to the number of engine rotations sensed by an engine rotation sensor 8. As a result, the tuning frequency of the said damper A can be switched in two or more steps instantaneously while a vehicle is running and the resonance of the vehicle whose resonant frequency is varied according to the number of engine rotations, can effectively be suppressed.