EXHAUST EMISSION CONTROL DEVICE FOR INTERNAL COMBUSTION ENGINE

摘要

PROBLEM TO BE SOLVED: To remarkably reduce combustible HC exhausted to atmosphere and actuate an exhaust turbocharger during acceleration at once. SOLUTION: An exhaust turbine 23 of an exhaust turbocharger 15 and an exhaust control valve 28 are arranged inside an exhaust passage. The exhaust control valve 28 is substantially fully closed during warming up the engine and under low load operation after it. An injection amount of main fuel is increased compared to an optimum injection amount at the time of full closing of the exhaust control valve. Sub-fuel is additionally injected during an expansion process. The exhaust control valve 28 is then fully opened when acceleration is carried out under substantially full closing of the exhaust control valve 28.