HYBRID VIBRATION DAMPING DEVICE

PROBLEM TO BE SOLVED: To expand an adjusting range of a natural period of a mass damper, and simplify a structure by fixing a pendulum to a low speed side rotary shaft of a speed reducer, fixing a pinion to a high speed side rotary shaft, and meshing the pinion with a rack installed on a horizontally moving mass arranged on a structure. SOLUTION: A pendulum 5 is fixed to a low speed side rotary shaft of a speed reducer 3, and a pinion is fixed to a high speed side rotary shaft. A horizontally moving mass 8 is arranged on a structure 50 so as to reciprocate in the same direction as the pendulum 5, and the pinion is meshed with a rack installed on the horizontally moving mass 8. When swinging in the arrow X1 direction is caused in the structure 50, a reciprocally rotating motor rotates in the clockwise direction, and the pendulum 5 swings in the arrow (a) direction, and the horizontally moving mass 8 moves in the same direction. When swinging in the arrow X2 direction is caused in the structure 50, the reciprocally rotating motor rotates in the anticlockwise direction, and the pendulum 5 swings in the arrow (b) direction, and the horizontally moving mass 8 moves in the same direction, and damps vibration of the structure 50.