| 摘要 |
PURPOSE:To impart excellent heat resistance and good response to the title detector and to adapt said detector to a wide range from a lean region to a rich region by forming the gas diffusion layer convering the entire surface of the outside electrode of a solid-state electrolytic element from porous glass. CONSTITUTION:Porous memberane-like electrodes 2a, 2b are provided to the inner and outer surfaces of a solid-state electrolytic element 1 composed of oxygen ion conductive metal oxide and the electrode 2b is covered with a gas diffusion layer composed of porous electric insulating metal oxide. Constant voltage is applied between the electrodes 2a, 2b to ionize oxygen in the atmosphere in which the element 1 is placed and the formed oxygen ion is diffused in the element to measure the air/fuel ratio to the flow rate of the oxygen ion. At this time, the diffusion layer 3 is formed from porous glass having uniform pores and low in a void ratio and has the optimum gas diffusion function and can be made thin. Therefore, the generation of heat strain due to the difference of a coefficient of thermal expansion with the element 1 is reduced and a crack is hard to generate and response and productivity are enhanced. |
