| 摘要 |
PURPOSE:To enable production of an oxygen sensor which consumes less electricity and permits temp. control of an element with high accuracy by laminating solid electrolyte plates, disposing porous electrodes on the mating surface thereof and the opposite surface thereof, heating the electrolyte plates by a sheathed heater provided via an insulating layer on the outside surface of the electrodes and taking out the signal voltage relating to the oxygen concn. in the gas to be measured. CONSTITUTION:A sensor element 1A is constituted by providing porous electrodes 5-7 on the mating surface of laminated solid electrolyte plates 3, 4 and the opposite surface thereof, laminating a solid electrolyte plate 8 on one side thereof, punching a gas-introducing chamber 15 in the position of the surface 9 facing the porous electrode 7, punching a gas-introducing hole 16 communicating said chamber 15 and the outside, disposing a heater 11 of the area smaller than the area of an insulating layer 10 consisting essentially of Al2O3 via said layer 10 on the outside surface of the plate 8 and providing a protective layer 12 consisting of Al2O3 covering the heater 11. If such element 1A is exposed to the gas to be measured, electricity is conducted to the heater 11 until the temp. of the gas to be measured attains 800 deg.C and the concn. of the oxygen in the gas admitted into the chamber 15 is easily measured with high accuracy irrespectively of the temp. of the gas to be measured. |
