PURPOSE: To enhance ignitability of an air-fuel mixture and enhance durability of an exhaust valve by disposing an exhaust valve, an ignition plug and an injector successively in the advance direction an intake swirl on the ceiling surface of a combustion chamber.
CONSTITUTION: In an upward flow, uni-flow type two-cycle engine CE, an exhaust port 7 disposed on the ceiling surface of a combustion chamber 5 is opened and closed by an exhaust valve 8, and a suction port 6 disposed on the side wall of a cylinder 3 is opened and closed by a piston 4. In this case, the exhaust valve 8, an ignition plug 13 and an injector 12 are disposed successively in the advance direction A of an intake swirl along the longitudinal- section surface of the cylinder 3 on the ceiling surface of the combustion chamber 5. Accordingly, a dense mixture collects around the ignition plug 13 and stratified so that ignitability of the mixture is greatly enhanced. Further, the exhaust valve 8 is cooled due to its contact with fuel particles or heat of vaporization, so that the heat damage is prevented, thereby enhancing durability of the exhaust valve 8.
YAMAUCHI HIROBUMI
KONDO MITSUNORI
YASUOKA TAKEHIKO
