Piezoelectric measured value transducer device e.g. for use in oscillators, has AC current generator as trigger circuit connected to control device such that its status changes as sign of operating current changes

摘要

Control device forming a synchronizing unit (14) synchronizes AC voltage generator by means of operating current, and is connected to a resonant circuit (11) and input trigger circuit (13) to deliver an input control signal (S) which changes-over when sign of operating current changes. Synchronizing unit includes power transistors (T1,T2), the base currents of which represent operating currents, and the collector currents produce at input of trigger circuit periodic pulses which represent its control signal (S). Resonant circuit is connected to the control circuit (12) by two wires (15,16), and transmission level of measured value on wire (16) is adjusted by resistor (R4).