TWO-CYCLE INTERNAL COMBUSTION ENGINE

摘要

PROBLEM TO BE SOLVED: To increase the speed of a uniflow two-cycle internal combustion engine having a poppet exhaust valve 6 installed at the top part of a cylinder 2 incorporating a piston 3 and a scavenging port 8 provided in the lower part of the cylinder. SOLUTION: A second exhaust valve (rotary valve) opening only for a period L2 smaller than the valve-open period L3 of the poppet exhaust valve 6 in the open period is disposed in an exhaust passage 11 from the poppet exhaust valve 6. The exhausting of exhaust gas is controlled by the second exhaust valve.