Transducer measurement system with differential pneumatic amplifier - uses two oppositely phased intermediate signals for error reduction

摘要

A device for determination of a measurement value has a transducer producing an intermediate signal characteristic of the measured parameter and inputs it to a pneumatic amplifier. The amplifier produces an output signal delayed relative to the intermediate signal. The device is designed to reduce asymmetrically magnified output signals when the intermediate signal is subject to HF, periodic, and/or statistically varying oscillations and to reduce null point drift experienced with slowly varying physical parameters. The transducer produces two intermediate signals of opposite phase which are input to a differential pneumatic amplifier whose output is proportional to the intermediate signal difference and corresponds to the average measurement value when the intermediate signals are of equal magnitude.