Sensor arrangement for detecting state of rotor motion - includes two sensors with resonant circuits damped differently by different regions on rotor

摘要

Two sensors are provided adjacent to the rotor. Each sensor contains a resonant circuit damped differently by two sectors of the rotor with different magnetic properties. The rate of decay of oscillations caused by pulsed stimulation depends on the magnetic properties of the sector next to the sensor and is evaluated to determine the motion state. An evaluation circuit compares the numbers of oscillations in successive evaluation cycles until the oscillation has decayed below a threshold and produces a signal corresp. to the sign of the difference. The motion state signal is derived from these signals by a logic circuit. USE/ADVANTAGE - E.g. for water, electricity, or gas meters. Reliable sensor signal evaluation is achieved with low cost circuit insensitive to external influences.