| 摘要 |
A combustion control apparatus operates an internal combustion engine in a split retard combustion mode during regenerating an exhaust purifier such as a NOx trap. In the split retard combustion mode, the combustion control apparatus controls a first fuel injection to cause preliminary combustion at or near top dead center, and controls a second fuel injection to cause main combustion after an end of the preliminary combustion. In this manner, the combustion control apparatus controls an exhaust gas temperature, or an exhaust air-fuel ratio, without increasing exhaust smoke. During the split retard combustion mode, the combustion control apparatus controls the excess air ratio to vary the exhaust gas temperature, if there is a request for shifting the exhaust gas temperature. The combustion control apparatus adjusts the second fuel injection timing in accordance with the excess air ratio.
|
