Crankcase compression two-stroke engine

摘要

By means of the invention a crankcase compression two-stroke engine of comparatively simple construction is created which can be operated with low fuel consumption and which discharges an exhaust gas with a comparatively low hydrocarbon concentration. The engine comprises a crankcase (5), a piston (2), a cylinder (1), connected to the crankcase (5) and provided in its lower part with an exhaust port (40), which is opened and closed by the piston (2), and a cylinder head (8) fitted to its upper end, which together with the cylinder (1) and the piston (2) forms a combustion chamber (9). In the upper part of the cylinder (1) a disc scavenging valve (21) is provided, which can be opened towards the combustion chamber (9). A diaphragm actuator (100) serves for actuation of the scavenging valve (21) by means of the pressure prevailing in the crankcase (5); it is provided with a diaphragm which is acted upon one side by the pressure prevailing in the crankcase (5) and on the other side by the pressure of a spring (29). A port (23a) for transmitting the pressure from the crankcase (5) into the diaphragm actuator (100) is connected to a scavenging port (23). A fuel feed system for feeding fuel into the scavenging port can be connected thereto. <IMAGE>