| 摘要 |
PURPOSE:To effectively attenuate vibration of a vibrating body by providing a rotary shaft which runs at a speed proportional to revolution speed of a vibration generating source, with centrifugal pendulums which are capable of being vibrated in the axial direction of the shaft and by making the natural frequency of the pendulums equal to the frequency of the vibrating body. CONSTITUTION:A pendulum supporting disc 2 is fit to a rotary shaft 1 and centrifugal pendulums 4 are attached around the circumferential face of the disc 2 via pendulum supporting plates 3. When the rotary shaft 1 is turned, the pendulums 4 are horizontally extended and become substantially horizontal at a reqular revolution speed of a main engine. When the pendulum mechanisms are mounted at needed positions on a hull which makes vertical vibration at a secondary frequency, (that is, a double frequency of a revolution speed of the main engine), the pendulums 4 is tuned to said frequency and therefore vibrated up and down. Inertia forces of the vibration at respective pendulums are concentrated and then transmitted to a hull structure via a thrust bearing 8, a casing 12 and a deck to balance a vibromotive force or a vibration energy of the hull, hence absorbing the vibration of the hull structure to damp it down. |
