To provide a crankcase compression type 2-cycle engine which can reutilize the unburned component in an exhaust gas, and can reduce the concentration of the hydrocarbon in the exhaust gas, as well as can improve the fuel consumption
An exhaust gas chamber 23 set to be in a negative pressure by utilizing the pressure variation in a crankcase 2; a communication passage 24 which penetrates the exhaust gas chamber 23 and the inside of the crankcase 2, and has a means 25 to permit only the gas flow in the direction to the inside of the crankcase 2; and an exhaust gas leading-in passage 26 which has means 31 and 32 to make its passage in the communicating condition at the latter phase of the exhaust stroke; are provided. Of the exhaust gas exhausted from an exhaust port 11 during the exhaust stroke, only the exhaust gas exhausted at the latter phase of the exhaust stroke is extracted, it is led in to the crankcase 2 at the compression stroke, it is fed into a combustion chamber 4 together with the mixed gas led in to the crankcase 2, and the unburned component in the exhaust gas is recirculated, so as to clean the exhaust gas.
NAKACHI MASAAKI
KOBAYASHI YOSHIO
