Patent ID: 6026779
Filing Date: 2000-02-22
Classification: F02B,F02D

Abstract:
A cylinder direct-injection spark-ignition engine using at least a homogeneous combustion mode where early fuel-injection on intake stroke produces a homogeneous air-fuel mixture and a stratified combustion mode where late fuel-injection on compression stroke produces a stratified air-fuel mixture, comprising:a control unit configured to be connected to at least an electronic fuel injection system;said control unit comprising:a combustion switching section connected to the electronic fuel injection system for switching between the homogeneous combustion mode and the stratified combustion mode depending on an engine operating condition;a torque-correction demand section for demanding a torque correction of the cylinder direct-injection spark-ignition engine depending on the engine operating condition;a torque-correction section for making the torque correction by manipulating one of a first unique manipulated variable used in the homogeneous combustion mode and a second unique manipulated variable used in the stratified combustion mode, said first and second unique manipulated variables being different from each other; anda combustion-switching permission decision section for deciding whether execution of a combustion mode change ought to be made, depending on a direction of switching from one of the combustion modes to another combustion mode, when a demand for switching between the combustion modes occurs during the torque correction,wherein said combustion-switching section performs a switching operation from one of the combustion modes to another combustion mode, only when the combustion mode change is permitted by said combustion-switching permission decision section.