MOTORE A BENZINA A COMBUSTIONE INTERNA

摘要

An internal combustion gasoline engine comprises a determined region which is so formed in an exhaust passage from an exhaust valve to a thermal reactor as to pass exhaust gases therethrough in their discharging order, a secondary air passage with a check valve means communicating with the exhaust port near the exhaust valve, and means for maintaining the temperature of exhaust gases over the trigger temperature of the thermal reactor. The exhaust passage has a volume equal to or more than the displacement of the engine and less than four times the displacement volume and has a cross-sectional area less than three times the opening area of the exhaust valve.