| 摘要 |
PROBLEM TO BE SOLVED: To provide an air-fuel ratio sensor capable of measuring an air-fuel ratio accurately even in the case of reduction in the concentration of gaseous oxygen in a gas to be measured. SOLUTION: An air-fuel ratio sensor is formed of an oxygen ion-conductive solid electrolyte body 131, a measuring electrode 111 provided at a main surface of the solid electrolyte body 131 and exposed to a gas to be measured, a reference electrode 112 provided at the other main surface opposing to the main surface of the solid electrolyte body 131 and at a location facing the measuring electrode 111 and exposed to a reference gas, and a reference gas chamber 10 in which the reference electrode 112 is arranged. An oxygen pump cell 12 formed of a pair of pump electrodes 121 and 122 is provided for the solid electrolyte body 131 and is constituted so as to introduce gaseous oxygen contained in the gas to be measured to the reference gas chamber by the impression of a voltage. |
