| 摘要 |
PROBLEM TO BE SOLVED: To provide a limiting-current type oxygen sensor apparatus and a sensor drive method whereby an oxygen concentration can be measured stably and highly accurately for a long time. SOLUTION: An oxygen sensor 10 of the apparatus consists of an ion conductor 11, a pair of porous electrode 12a, 12b set at both faces of the ion conductor 11 for generating an electric field, a cap 13 covering the side of the electrode 12a, and a gas diffusion hole 14 formed at the center of the cap. A heater 15 is provided on the cap 13 to heat the ion conductor 11. A power source E2 always feeds electricity to the heater 15. Switches SW1, SW2 and, a timer 21 and an inverter 22 for alternately turning ON/OFF the switches are provided as a driving circuit 20 to impress a source monitor voltage intermittently between the pair of the electrodes 12a and 12b from a power source E1. |
