| 摘要 |
PROBLEM TO BE SOLVED: To significantly reduce generation amount of smoke and NOx over a wide operation region and moreover restrain deterioration of fuel consumption. SOLUTION: When engine output is in an intermediate load region, a fuel injection time is delayed in a range where the fuel consumption amount is not greatly increased, (for example, in a range where the fuel consumption deterioration is 5% or less), and an EGR amount is increased compared to the conventional level, and an EGR amount is increased to the region wherein the smoke amount is reduced after peaking. When the engine output is in a low load region, the EGR amount is increased further than in the case of the intermediate load region, and the fuel injection time is made to advance to a degree where the generation amount of the NOx is not increased greatly. Thus, the generation both of the smoke and the NOx can be restrained over a wide operation region, while improving the fuel consumption. |
