Portable electronic gas leakage detector - has solid gas sensor and gas suction pump with conducting wire forming electrical signal from conductivity variation

摘要

A portable electronic gas leak detector for very low leakage rates indicates the magnitude of a leak by a variable lamp intensity and/or buzzer noise. A solid gas sensor has a block of sintered metal oxide whose thermal conductivity varies by chemical absorption. A conducting wire converts the thermal conductivity variation into an electrical signal. A suction pump connected to a gas suction channel draws any leakage gas into contact with the sensor. The output pulse frequency of a variable frequency oscillator varies according to a voltage input to the oscillator from the solid gas sensor. The variable frequency of the oscillator output pulses controls the frequency of an optical or acoustic indicator which varies between upper and lower limits corresp. to defined gas concs.