| 摘要 |
PROBLEM TO BE SOLVED: To provide an exhaust gas sensor which can selectively detect a specific hydrocarbon component and obtain information related to concentrations of different components or component groups separately. SOLUTION: Two elements 3, 4, one functioning as an oxygen concentration cell element and the other functioning as an oxygen pump element, are set to face each other via a gap 15. Electrodes 10-13 of different oxidation catalyst activation differences are arranged at both faces of each element 3, 4. An exhaust gas is introduced to both sides of the element functioning as the oxygen concentration cell element. A difference of oxygen consumption amounts is brought about at both sides of the oxygen concentration cell element due to oxidation (burning) of a component to be detected of the exhaust gas, whereby a concentration cell electromotive force is generated. The element functioning as the oxygen pump element sucks in or out the oxygen to the gap so as to make the concentration cell electromotive force constant. A concentration of the component to be detected in the exhaust gas is detected from a current value of the oxygen pump. |
