To ensure improvement in the fuel consumption in the partial loading and to reduce the load for reducing emission in a direct injection type internal combustion engine.
The volume of a fuel/air mixture forming area 30 is controlled by forming a volume variable fuel/air mixture area 30 in a sub chamber 24 by movable pistons 28-1 and 28-2, and controlling the positions of the movable pistons 28-1 and 28-2 according to the injection quantity of the fuel injected from an injection valve 20 into the fuel/air mixture forming area 30. When the load is adjusted by the fuel injection, the load can be adjusted in a substantially uniform air-fuel ratio without forming the fuel/air mixture concentration distribution in the fuel/air mixture forming area 30 in a stratified manner. Therefore, improvement in the fuel consumption is ensured in the partial loading, and the load in reducing emission can be reduced.
KOIKE MAKOTO
HATTORI YOSHIAKI
Jun Ishida