Patent ID: 7445700
Filing Date: 2008-11-04
Classification: G01N

Abstract:
1. A gas sensor for measuring an amount of a measurement gas component contained in a measurement gas existing in an external space, said gas sensor at least comprising: a substrate composed of a solid electrolyte to make contact with the external space; an internal space formed at the inside of said substrate; a gas-introducing port for introducing measurement gas from the external space into said internal space; a clogging-preventative section provided in series between said gas-introducing port and said internal space, a front aperture of said clogging-preventive section defining said gas-introducing port; a diffusion rate-determining slit passage provided in series between said clogging-preventative section and said internal space, for introducing measurement gas from the external space into said internal space under a predetermined diffusion resistance, said slit passage having, when viewed in a plane substantially perpendicular to a longitudinal extension axis thereof, two dimensions defining a cross-sectional area, wherein the cross-sectional area of said slit passage is less than that of said clogging-preventative section and at least one dimension of said slit passage is not more than 10 microns; and pumping means including an inner pumping electrode and an outer pumping electrode formed at the inside and outside of said internal space respectively, for pumping-processing oxygen contained in the measurement gas introduced from the external space, on the basis of a control voltage applied between said electrodes.