| 摘要 |
PROBLEM TO BE SOLVED: To provide a gas sensor which has an excellent response characteristic and a high resistivity against heat and is capable of accurately performing temperature control of a solid electrolyte without being affected by a temperature of gas to be detected.SOLUTION: An outer surface 61A and an inner surface of a solid electrolyte 61 in a bottomed cylindrical shape are respectively provided with a detection electrode 63D and a reference electrode. A heater which is inserted to a cylindrical hole in a detection element 6 is in contact with the reference electrode at a point Q. The detection electrode 63D is partially formed in the vicinity of a position facing the point Q via the solid electrolyte 61 and its surface area is 8 to 20% of the surface area of a detection part 64. Thus, an electronic control device for performing temperature control of the solid electrolyte 61 can accurately detect only the temperature of the solid electrolyte 61 in the vicinity of the point Q where the highest temperature is reached during heating by a heater. Furthermore, because a formed amount of the detection electrode 63D is minimized and is limited to the vicinity of the point Q, an oxygen sensor can achieve a resistivity against high temperature as well as an excellent responsiveness which is not affected by an inactive solid electrolyte 61. |
