OSCILLATOR TYPE FORCE MEASURING SYSTEM INSENSITIVE TO INPUT VOLTAGE VARIATIONS

摘要

A force measuring system includes an oscillator energized by an input voltage and having a tank circuit and means for changing the impedance of the tank circuit in accordance with the movement of an element in response to an applied force. The oscillator output voltage changes with changes in impedance and is compared to the input voltage to cancel out input voltage variations. The difference between the compared voltages is used to apply a restoring force to the movable element and the restoring force is a measurement of the applied force.