摘要:
A feedback control system for an air-fuel ratio according to the present invention comprises a first oxygen sensor for detecting the oxygen concentration of exhaust gas flowing through a first exhaust pipe of an internal combustion engine, a second oxygen sensor for detecting the oxygen concentration of the exhaust gas passed through an exhaust gas disposer in a common exhaust passage which is connected with both first and second exhaust pipes of the engine, and an electronic control unit for calculating the amount of fuel supply to each cylinder of the engine in accordance with the oxygen concentration of the exhaust gas detected by means of the first oxygen sensor. The electronic control unit contains therein a correction circuit for correcting the amount of fuel supply to that cylinder of the engine which is associated with the second exhaust pipe, in accordance with the oxygen concentration of the exhaust gas detected by means of the second oxygen sensor.
摘要:
Flammable fine particles (particulates) consisting principally of carbon and hydrocarbons are discharged from a diesel engine to its exhaust system. A diesel particulate oxidizer (DPO) is disposed in the exhaust passage for collecting and burning the particulates without allowing the particulates to be discharged directly to the atmosphere. This DPO comprises a ceramic foam with catalyst. When the quantity of particulates collected is above a predetermined value, the DPO will undergo clogging. To prevent this, a high temperature gas containing oxygen is fed to the DPO to burn (regenerate) the collected particulates. In order to accelerate the normal regeneration of the DPO, there are provided a regeneration means for making a retard control of the fuel injection timing in the diesel engine, and a regeneration timing control means for controlling the operation of the regeneration means. Further, there is provided a regeneration timing detection means for detecting the regeneration timing of the DPO.