| 摘要 |
PROBLEM TO BE SOLVED: To achieve early activation of a catalyst and HC reduction by after-burning with a considerable delay of ignition timing. SOLUTION: At the cold start of an internal combustion engine which requires the early temperature rise of a catalytic converter, the ignition timing is set after the compression top dead center, and super retard combustion of injecting fuel before the ignition timing and after the compression top dead center is performed. At this time, the fuel pressure is set higher than that in normal stratified combustion operation by a pressure regulator. Turbulence in a cylinder is improved by high pressure fuel injection immediately before the ignition timing, and flame propagation is accelerated to achieve stable combustion. Further, the larger the load is, the higher the fuel pressure is set. Turbulence is thereby formed positively by the large force of complete penetration. COPYRIGHT: (C)2007,JPO&INPIT |
