| 摘要 |
PURPOSE:To obtain an efficient exhaust gas purifying system by providing two O2-sensor elements in a single O2-sensor and using the output of the O2- sensor element on the downstream side as the auxiliary signal of the control of an air/fuel ratio. CONSTITUTION:An O2-sensor 17 has the first and second segments 17A, 17B and is constituted so that the first segment 17A is good in response but low in catalytic capacity and the second segment 17B is high in catalytic capacity but slow in response. Since these two segments are arranged under the almost same temp. environment, the trouble generated in a conventional dual O2-sensor system is not generated. The output of the first segment 17A is compared with a reference value REF 1 by a comparator 100a to be directly used in control. The output of the second segment 17B is subtracted from a reference value REF 2 and the deviation between them is subjected to proportional integrating operation by operators 100b, 100c to be used in the correction of the reference value REF 1. |
