Arrangement for generating natural resonant oscillations of a mechanical oscillating system

摘要

An arrangement for generating natural resonant oscillations of a mechanical oscillating system includes an electromechanical oscillation exciter which on excitation by an electrical excitation signal generates a drive force setting the oscillating system in mechanical oscillations, an oscillation sensor which is formed as displacement sensor and senses the mechanical oscillations of the oscillating system and converts them to an electrical sensor signal, and an excitation circuit which receives the sensor signal and supplies to the oscillation exciter the electrical excitation signal with the frequency of the sensor signal. The excitation circuit includes a phase control circuit which controls the phase position of the excitation signal in dependence upon the phase position of the sensor signal. A phase shift circuit produces a phase displacement of 90 between the sensor signal and the excitation signal so that the phase condition for the excitation of the mechanical oscillations at the natural resonant frequency of the mechanical oscillating system is fulfilled. This makes it possible to maintain the natural resonant frequency of the mechanical oscillating system with very great accuracy and high stability with time even with oscillating systems of high quality.