SPARK IGNITION ENGINE OF FUEL CYLINDER INJECTION TYPE

摘要

PROBLEM TO BE SOLVED: To secure an optimal intake air fluidity in a cylinder for every driving condition and to improve various performances by employing two-fluid type fuel injection valve independently injecting the fuel and a pressure air and providing a means variably controlling the injection timing and period of the pressure air in a stratified combustion drive and homogeneous combustion drive. SOLUTION: A two-fluid type fuel injection valve independently injection fuel and a pressure air is used for a fuel injection valve 10 and controlled by an engine control unit 11 (ECU). The ECU 11 controls an ignition plug 9 and a fuel injection valve 10 based on air volume signal detected by an air flowmeter in a intake passage 12, and load signals detected by a throttle sensor of a throttle valve 14. The ECU 11 has a pressure air injection period variable means 11A and a pressure air injection timing variable means 11B arranged therein in a form of software. This constitution can changed the injection timing and period of the pressure air according to respective driving conditions of a stratified combustion drive and a homogeneous combustion drive.