| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an exhaust emission control device of an internal combustion engine capable of surely purifying exhaust even when a temperature of a catalyst is low.SOLUTION: A lean operation is performed so that an air-fuel ratio becomes a lean air-fuel ratio, when an engine water temperature is 0°C or more, and a multifunctional catalyst temperature Tm is less than a second prescribed temperature. A slightly-rich operation is performed so that the air-fuel ratio becomes slightly rich, when the multifunctional catalyst temperature Tm is the second prescribed temperature or more and less than a third prescribed temperature. A PM combustion operation is performed so that PM accumulated on the multifunctional catalyst is burnt, when a multifunctional catalyst PM accumulation amount is a threshold value or more, and the multifunctional catalyst temperature Tm is a fifth prescribed temperature or more.</p> |
