| 摘要 |
<P>PROBLEM TO BE SOLVED: To satisfactorily change over combustion mode between compression ignition combustion (CI combustion) and spark ignition combustion (SI combustion) while avoiding knocking or the like. <P>SOLUTION: Main fuel (gasoline) is injected to an intake port from a first fuel injection valve and air fuel pre-mixture is formed in a combustion chamber. In CI combustion, the air fuel pre-mixture is burned with trigger by self ignition combustion of ignition fuel (gas oil) during compression stroke injected from a second fuel injection valve 14. In SI combustion, the air fuel pre-mixture is ignited by a spark plug 15 and is burned with flame propagation combustion. Change over between CI combustion and SI combustion is done through third combustion (CI-SI combustion). In CI-SI combustion, effective compression ratio is set smaller than that in CI combustion, injection quantity of the ignition fuel is reduced, and air fuel pre-mixture is burned with flame propagation combustion with trigger by self ignition combustion of the ignition fuel. <P>COPYRIGHT: (C)2009,JPO&INPIT |
