Patent ID: 7322322

Claim:
A two-stroke internal combustion engine, comprising: a cylinder chamber and a crank chamber defined by a piston fittingly inserted in a cylinder; a plurality of air-fuel mixture passageways having air-fuel mixture outlets open to the cylinder chamber to provide communication between the cylinder chamber and crank chamber; a plurality of air passageways having air outlets open to the cylinder chamber to provide communication between the cylinder chamber and crank chamber; at least one air-feeding port to feed air into the crank chamber; a plurality of inlet ports to supply an air-fuel mixture from the air-fuel mixture outlets to the air-fuel mixture passageways through air-fuel mixture introduction recesses formed in the outer surface of the piston; and at least one exhaust port located diametrically opposite from the air-feeding port to discharge combustion gas outside from the cylinder chamber, each of the air-fuel mixture outlets, the air outlets, the air-feeding port, the inlet ports and the exhaust port being opened and closed by the piston; the air-fuel mixture outlets being located nearer to the inlet ports than the exhaust port, and the air outlets being located nearer to the exhaust port than the inlet ports; in each compression stroke of the piston, air being charged into the crank chamber from the air-feeding port, and air-fuel mixture being charged into the air-fuel mixture passageways from the inlet ports through the air-fuel mixture introduction recesses of the piston and air-fuel mixture outlets; and in each exhaust stroke in which the exhaust port is opened, the air passageways and the air-fuel mixture passageways being opened such that air is supplied into the cylinder chamber from the crank chamber through the air passageways and the air outlets to interpose between the air-fuel mixture having entered into the cylinder chamber from the air-fuel mixture passageways through the air-fuel mixture outlets and the combustion gas in the cylinder chamber.