| 摘要 |
PURPOSE:To prevent the self-ignition of the air-fuel mixture by providing an exhaust gas recirculating valve in an exhaust gas recirculating passage communicating the intake passage and the exhaust passage of an internal combustion engine and opening it when the load of the internal combustion engine is the preset value. CONSTITUTION:An exhaust gas recirculating conduit pipe 18 is branched from an exhaust pipe 17 at the downstream of a main muffler 16 of a two-cycle internal combustion engine. The conduit pipe 18 is connected between a mechanical supercharger 5 in an intake duct 7 and a throttle valve 8. A switch valve 20 is arranged in the conduit pipe 18. The switch valve 20 is controlled by an electronic control unit 30 based on detection signals from an air flow meter 9, an oxygen concentration detector 14 and a rotating speed sensor 21. When the load of the internal combustion engine 1 is between the preset upper limit value and the lower limit value, the switch valve 20 is opened to recirculate the exhaust gas in the intake duct 7. The self-ignition of the air-fuel mixture is thereby prevented. |
