Exhaust gas recirculation system for crankcase scavenged two cycle engine

摘要

A two cycle crankcase scavenged internal combustion engine having an exhaust gas recirculation system. Exhaust gas from the coolest part of the exhaust muffler is recirculated back to the crankcase in a controlled discrete charge on each cycle of the engine. A recirculation port extends through the cylinder sidewall and is opened briefly during the compression stroke of the piston to thereby enhance vaporization of the fuel and increase velocity of the scavenging air-fuel mixture into the combustion chamber.