| 摘要 |
PURPOSE:To enable the detection of thinner side of the air-fuel ratio than the theoretical air-fuel ratio by regulating the oxygen partial pressure of the reference gas layer of a solid electrolytic element contacting an exhaust gas with another solid electrolyte contacting the element. CONSTITUTION:First and second solid electrolytic elements 21 and 22 are each formed in a shape of a bag tube and the second solid electrolytic element 22 is inserted into the inside of the first solid electrolytic element 21 sandwitching a reference gas layer 23 while the base section at the upper end thereof is compressed through a conductive seal layer 24. Porous platinum electrodes 27-30 are formed on both sides of these solid electrolytic elements. The electrode 27 is made to conduct to a plug body fitting 31 while the electrdes 28 and 29 both conduct to a conductive seal layer 24, all connected electrically to a terminal 38. The electrode 30 is connected to a terminal 40. A sensor thus arranged is mounted to an exhaust manifold and an excitation voltage is provided between the first terminal 40 and the second terminal 38 to regulate the regerence oxygen concentration whereby the mixed gas to be supplied is controlled depending on the voltage between the earth and the second terminal 38. |
