Nutation damper system comprising a control member for varying a natural frequency of a pendulum.

摘要

In a nutation damper system comprising a pendulum (30, 33, 34, 38) swingable at a natural fequency and a block element (35) operable in cooperation with the pendulum to damp nutation having a nutation frequency, a control member (40) is electromagnetically coupled to the pendulum to vary the natural frequency to a forced frequency substantially equal to the nutation frequency. The control member comprises an electromagnetic coil supplied as a control signal with an electric current produced by a control signal circuit and proportional to a square of the nutation frequency. The block element may comprise either a permanent magnet or an electromagnet when a pendulum weight of the pendulum is of an electrical conductor. The electromagnet may intermittently be energized by a power source circuit. Alternatively, the block element may be of an electrical conductor when the pendulum weight is of a permanent magnet.