Equations of small vibrations of a centrifuge rotor which is a working head (an accelerator) of the stone crusher are introduced. The rotor is held in the vertical position by the viscoelastic plates, and it is under action of the sequence of the pulses from the stones in the accelerator. The influence of its impacts with the centrifuge frame on the rotor dynamics is investigated. Three regimes of the rotor motion are found. The examples are presented.