Rapid, low-noise gas sensor of Kelvin probe type - uses probe output signal to measure difference between work functions of probe capacitor plates

摘要

A rapid gas sensor, for determining component concns. in a gas mixt., comprises a Kelvin probe, the oscillation of which is affected by the adsorbable compsn. of the gas mixt. to be evaluated. The probe output signal, obtd. by zero adjustment by a voltage supplied from a voltage regulating circuit, is used as a measure of the difference between the work functions of the probe capacitor plates and thus as a measure of the adsorbable compsn., the probe output signal pref. being differentiated by an RC differentiator. ADVANTAGE - The sensor has a short reaction time, operates reliably and is inexpensive to mfr.