| 摘要 |
PROBLEM TO BE SOLVED: To prevent damage of electrodes and improve response characteristics between a sensing cell and a pumping cell by using the first electrode and the third electrode as the sensing cells generating electromotive force according to oxygen concentration ratio between each of the electrodes. SOLUTION: The first - third electrodes 32a, 32b, 33 are coated on both sides of a solid electrolyte 31 and electrodes 32a, 32b in the bottom of the electrolyte 31 are in contact with air in the atmosphere through an air duct whose one side is closed. The electrode 32a out of them is an electrode for a sensing cell which generates electromotive force according to difference between exhaust gas and oxygen partial pressure in air and the electrode 32b is an electrode for a pumping cell which pumps the oxygen in the desired direction by applying voltage. The electrode 33 in the top of the electrolyte 31 forms the sensing cell along with the electrode 32a and at the same time forms the pumping cell along with the electrode 32b. On the other hand, a porous film 35 for diffusion control is coated on the electrode 33 so as to be used for a diffusion control barrier. |
