| 摘要 |
PURPOSE:To obtain a low-power and approximately-linear output characteristic and an excellent response in a wide range of oxygen concentration, by providing an oxygen diffusion resistant porous layer on the electrode layer of an oxygen pump element at least on the gap portion side. CONSTITUTION:A wall body member 3 on one side of a gap portion is formed of a first board-shaped solid electrolytic substance which is made to work as an oxygen pump element. On said member 3 a combination layer of electrode layers 301 and 302 of heat-resistant metal with thick porous electrode covering layers 310 and 320 of ceramic, which are superposed on the former, is connected. Another wall body member 4 on the other side of the gap portion is formed of a second board-shaped solid electrolytic substance which works as an electric cell element, and on this member 3 a combination layer of thin electrode layers 401 and 402 of heat-resistant metal with thick porous electrode covering layers 410 and 420 of ceramic is connected in the same way as the above. By setting the ratio W/S of the gap W to the depth S of diffusion of oxygen gas produced in the gap portion to be 0.13 or less, or more preferably to be 0.10 or less, a linear characteristic can be obtained with a small output current and in a wide range of oxygen concentration. |
