Patent ID: 6205843
Filing Date: 2001-03-27
Classification: G01N

Abstract:
A gas sensing element comprising:a sample gas chamber into which a sample gas is introduced;a reference gas chamber into which a reference gas is introduced;a sensor cell having a measuring electrode located in said sample gas chamber and a reference electrode located in said reference gas chamber for detecting the concentration of a specific gas contained in said sample gas;an oxygen pump cell having an inside pump electrode located in said sample gas chamber and an outside pump electrode located on an outside surface thereof for pumping oxygen gas from said sample gas chamber to an outside; andan introducing passage including at least one pinhole extending across said oxygen pump cell for introducing said sample gas from the outside into said sample gas chamber,whereina porous diffusion resistive layer is provided on said outside surface of said oxygen pump cell so as to cover a portion corresponding to said introducing passage and to help reduce the effect of temperature dependency upon gas element output for a properly sized and placed pinhole.