CONTROL DEVICE FOR SPARK IGNITION TYPE DIRECT INJECTION

摘要

PROBLEM TO BE SOLVED: To appropriately balance strength of a tumble flow formed in a combustion chamber and a pressure of a fuel spray injected from a fuel injection valve at the time of switching transition period of a combustion mode. SOLUTION: The control device for a spark ignition type direct injection engine is constituted such that a flammable mixed air is sedimented around an ignition plug 16 at the time of ignition by injecting a fuel so as to be opposed to the tumble flow in the state that the strength of the tumble flow is increased at a combustion mode of the lean state that an air/fuel ratio in at least a combustion chamber 6 is larger than a theoretical air fuel ratio. The tumble flow adjusting means is controlled such that the throttle state of a suction passage 31 is further strengthened at a downstream side of a suction amount adjusting means comprising the tumble flow adjusting valve 37 while maintaining an injection form of the fuel adapted for the combustion mode of the lean state until the air/fuel ratio in the combustion chamber 6 becomes a value approximately corresponding to the combustion mode of the rich state at the time of switching transition period from the combustion mode of the lean state to the combustion mode of the rich state. COPYRIGHT: (C)2003,JPO