| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent preignition when an engine is switched from a diesel combustion mode to a pre-mixed combustion mode and to suppress generation of excess noise caused by the preignition, in a diesel engine of direct injection of fuel type wherein advanced injection of fuel is performed in a first operation area H on a low load side and an EGR rate is set to be not less than a first set value to be in the pre-mixed combustion mode, and wherein a diesel combustion mode is performed in a second operation area D on a high load side and a high revolution speed side and the EGR rate is suppressed to be not more than a second set value. <P>SOLUTION: When the engine 1 is switched to a diesel combustion mode to the pre-mixed combustion mode and before an actual EGR rate reaches a target EGR rate of the first set value or more, an amount of fuel of the advanced injection is made to be relatively small to prevent the preignition. Further, When combustion of fuel of advanced injection is completed, additional fuel injection is performed to prevent torque fluctuation of the engine and increase of soot. An advanced injection amount of fuel is controlled to be smaller as larger the deviation is, depending on the deviation of the EGR rate before and after the switching of the combustion modes. <P>COPYRIGHT: (C)2004,JPO |
