PURPOSE: To increase the engine output by the simple constitution by carrying out fuel injection from an assisting fuel injection valve, together with an air assisting fuel injection valve in the high speed operation, in the constitution in which the air assisting fuel injection valve for directly jetting fuel into a combustion chamber is provided.
CONSTITUTION: Spark plugs 15a and 15b and air assisting fuel injection valves 16a and 16b are installed in the combustion chambers 14a and 14b for each cylinder of a two-cycle two-cylinder engine. Further, an assisting fuel injection valve 18 for directly jetting fuel into a crankcase C is installed into a suction passage 2, Though each fuel injection valve 16a, 16b, 18 is controlled by an electronic controller 13, almost all the parts of the demanded fuel quantity is supplied by the fuel injection from the fuel injection valves 16a and 16b in the low or intermediate speed revolution region of the engine, while the fuel injection quantity of the assisting fuel injection valve 18 is speedily increased so that the demanded fuel quantity is supplied, when the fuel injection quantity of each fuel injection valve 16a, 16b reaches a limit in the high speed revolution of the engine.
HASEGAWA TAKASHI
HANAWA KAORU
