Patent ID: 6338783
Filing Date: 2002-01-15
Classification: G01N

Abstract:
A gas sensor comprising:a first processing space and a first gas passage for introducing a measurement gas into said first processing space; a second processing space and a second gas passage for introducing a gas contained in said first processing space into said second processing space; an oxygen concentration detection element for measuring the oxygen concentration of the gas contained in said first processing space; a first oxygen pump means for pumping out oxygen from said first processing space or pumping oxygen into said first processing space so as to adjust to a predetermined level the oxygen concentration of the measurement gas introduced into said first processing space, which is measured by said oxygen concentration detection element; a second oxygen pump means for pumping into said second processing space a constant amount of oxygen for measuring the combustible gas component contained in the measurement gas; and a combustible gas component concentration detection means for pumping out oxygen from said second processing space under a constant applied voltage, so that a current output from said combustible gas component concentration detection element varies inversely to the amount of oxygen consumed by combustion of the combustible gas component contained in the gas introduced from said first processing space into said second processing space to thereby provide information regarding a detected concentration of the combustible gas component of the measurement gas, and at least one of said combustible gas component concentration detection means and second oxygen pump means comprises an oxidation catalyst exposed to said second processing space for accelerating combustion of a combustible gas component contained in the gas which has been introduced into said second processing space from said first processing space via the second gas passage.