Verfahren und Vorrichtung zur Steuerung des Luft-Kraftstoff-Verhältnisses bei Diesel-Verbrennungsmotoren

摘要

The air/fuel ratio of the combustion mixture in the cylinders (12) of an engine (10) is sensed and the sensed air/fuel ratio is controlled to a predetermined scheduled air/fuel ratio by controlling the amount of exhaust gases recirculated. When the exhaust gas recirculated is substantially zero, the air/fuel ratio is thereafter closed loop adjusted to a predetermined scheduled minimum air/fuel ratio when the sensed air/fuel ratio is less than the minimum and when the sensed air/fuel ratio is greater than the minimum while the operator command (26) is at a maximum thereby to provide precise fuel limiting at a predetermined fuel limit schedule.