Two-stroke engine with a rotating rotary disc valve for narrowing the cross-section of the exhaust pipe

摘要

The invention relates to a two-stroke engine 10 with at least one working cylinder 11, in which, during its movement between a top dead centre and bottom dead centre, a piston 17 which is articulated on a crankshaft 15 releases an outflow opening and at least one scavenging opening 19 for mixture inflow, it being possible, by way of the outflow opening, for combusted gases to be fed to an exhaust pipe via an outflow duct. In the case of said two-stroke engine 10, a rotary disc valve 21 is provided for the outflow duct 20, which valve rotates synchronously with the crankshaft and by means of which the cross-section of the outflow duct 20 is narrowed by approximately half when the piston 17 moves from the bottom dead centre to the top dead centre. In the upper part, oriented towards the top dead centre, of the outflow duct 20, the rotary disc valve 21 is mounted in the vicinity of the working cylinder 11, without special sealing and with a large amount of tolerance.