| 摘要 |
PROBLEM TO BE SOLVED: To save fuel consumption owing to lean combustion by stratified combustion at a low load, secure an output owing to uniform combustion in a high load region, and perform transition from the stratified combustion to the uniform combustion while securing excellent operability during the transition. SOLUTION: A stratified air supplying engine comprises a load detector 17, fuel suppliers 11, 13 and an igniter 8. At a low load, fuel is supplied at a rear stage to perform stratified combustion in such a manner that inflammable mixture air is unevenly dispersed around the igniter 8, while at a high load, the fuel is supplied early to perform uniform combustion in such a manner that the inflammable mixture air is dispersed in the entire combustion chamber 1. In controlling an engine output by gradually increasing a fuel injection quantity according to an increase in load, a transition region, in which early fuel injection and fuel injection at the rear stage are performed, is interposed between a stratified combustion region at the low load and a uniform combustion region at the high load. In the transition region, an air excess rateλexceeds 1 in the entire region and is decreased according to an increase in load. A controller 16 is provided for setting an increasing rate of the early fuel injection according to the increase in load more than an increasing rate of the whole fuel injection, and reducing a fuel injection quantity at the rear stage less than the early fuel injection quantity at the end of the transit region according to the increase in load. |
