| 摘要 |
PROBLEM TO BE SOLVED: To provide a small-sized and inexpensive oxide sensor capable of measuring oxide contained in gas to be measured with extremely high accuracy. SOLUTION: A measuring electrode 72 is arranged at a distance (d) becoming -3t<=d<=3t (wherein d is the distance of the measuring electrode 72 from the downstream direction end part of an inside pump electrode 64 in the positive direction from a first chamber 60 to a second chamber 76 and t is the height of the first chamber) with respect to the downstream direction end part of the inside pump electrode 64 in the first chamber 60 (the end part on the side of a second diffusion rate determining part 58). The oxygen partial pressure in the first chamber 60 is measured by using the measuring electrode 72 and a main pump cell 68 is subjected to feedback control on the basis of the measured value V1 to control the oxygen partial pressure in the first chamber 60 and, thereafter, gas to be measured is introduced into the second chamber 62, oxide in the gas to be measured is decomposed by a detection electrode 82 or a catalyst, and the oxygen partial pressure generated at this time is measured to calculate the concn. of oxide. |
