Shaft speed indicator device - has AC generator feeding frequency to voltage converter and stabiliser circuit giving reference voltage

摘要

An indicator device generates a voltage proportional to the instantaneous speed of a rotating shaft. It contains an a.c. generator and a voltage-to-frequency converter circuit. A rotating shaft (10) is coupled by means of a connecting member (11) to the generator (12). Connections (13) from the generator feed a frequency/voltage converter circuit (15) and a stabilising circuit (17). The generator gives an output current of which the frequency depends on the speed of rotation of the shaft and this is changed in the converter circuit to a speed-dependent voltage. The stabiliser circuit produces a DC output which serves as a reference voltage for the converter circuit.