| 摘要 |
PURPOSE:To restrict resonance in all the directions by a single dynamic vibration reducer, by providing a weight at the center of a derrick, providing leaf springs along respective surfaces of the weight by means of frames of the derrick and providing sliders among the weight and the leaf springs. CONSTITUTION:A grid-shaped cubic derrick 30 surrounding a weight 1 is provided at a vibrating portion of a construction and frames 31-36 forming sides of the derrick 30 have leaf springs 2, 2a-2e disposed thereon, the leaf springs being adjustable in their length so that an amount of motion of the weight in X, Y, and Z directions is supported. Further, there are disposed sliders 11b, 11c, 12b, 12c, 13b, and 13c among the leaf springs 2, 2a-2e and the weight 1 for producing frictional forces caused by vibration one another. As a result, when the characteristic frequency of the construction is caused to coincide with that of the dynamic vibration reducer, kinetic energy of the construction is converted into kinetic energy of the dynamic vibration reducer and further heat is produced by friction between the leaf springs and the sliders so that the vibration of the construction is damped and resonance of characteristic modes which are orthogonal each other is restricted by a single dynamic vibration reducer. |
