| 摘要 |
PURPOSE:To provide feedback control through which an air-fuel ratio is adjusted to a value constantly accurately responding to the state of the interior of a catalyst by a method wherein a control constant determined from the engine speed and a load is corrected according to a deviation between the balanced temperature of an exhaust system, estimated from the engine speed and a load of an internal combustion engine, and an actual temperature. CONSTITUTION:Based on the output of an air-fuel ratio sensor 51 to detect oxygen concentration in exhaust gas in an exhaust passage in which a catalyst 50 is located, feedback control of the air-fuel ratio of an internal combustion engine is adjusted to a stoichiometric air-fuel ratio by a means 52. In this case, the engine speed and the load of the internal combustion engine are detected by means 53 and 54. Based on detection results therefrom, a control constant of feedback control suitable for the state of the catalyst 50 when the internal combustion engine is in a balanced state is set by a means 55. Further, the balanced temperature of an exhaust system when the internal combustion engine is brought into a balanced state, is calculated by a means 56. Meanwhile, the actual temperature of the exhaust system is detected by a means 57. A correction factor to a control constant is calculated by a means 58 according to a deviation between the balanced temperature and the actual temperature and the control constant is corrected by a means 59.
|
