| 摘要 |
PURPOSE:To obtain an oxygen concentration detection output with excellent linearity over the lead and rich areas of an air fuel ratio by providing the 1st and the 2nd electrode couples on the internal and external wall surfaces of respective electrolyte wall parts of the 1st and the 2nd gas reservation chambers opposite each other across the internal and external wall surfaces. CONSTITUTION:The 1st gas reservation chamber 2 communicates with the outside through an intake hole 4 and the 2nd gas reservation chamber 3 communicates with the reservation chamber 2 through a communicating hole 5. The 1st electrode couples 11a and 11b, and 12a and 12b are provided on the internal and external wall surfaces of the reservation chamber 2 opposite each other across them, and the 2nd electrode couples 13a and 13b, and 14a and 14b are provided on the internal and external wall surfaces of the electrolyte chamber wall part 1 of the reservation chamber 3 opposite each other across the internal and external wall surfaces. Then a current supply circuit 21 supplies a current corresponding to the difference voltage between a voltage developed between the electrodes 12a and 12b and the 1st reference voltage source 26 to between the electrodes 11a and 11b and also supplies a current corresponding to the difference voltage between a voltage developed between the electrodes 14a and 14b and the 2nd reference voltage source 27 to between the electrodes 13 and 13b, thereby obtaining an oxygen concentration detected value corresponding to the supply current values. |
