Patent ID: 6932032

Claim:
A two-stroke engine including an engine in a portable handheld work apparatus, the two-stroke engine comprising: a cylinder having a cylinder wall; a piston mounted in said cylinder to undergo a reciprocating movement along a stroke path between top dead center and bottom dead center during operation of said engine; said cylinder and said piston conjointly delimiting a combustion chamber; a crankcase connected to said cylinder; a crankshaft rotatably mounted in said crankcase; a connecting rod connecting said piston to said crankshaft to permit said piston to drive said crankshaft as said piston reciprocates in said cylinder; an outlet for conducting exhaust gases away from said combustion chamber; a first channel for supplying fuel to said crankcase; a second channel for supplying substantially fuel-free air to said engine; first and second throttle flaps movably mounted in said first and second channels, respectively; a transfer channel for connecting said crankcase to said combustion chamber at predetermined positions of said piston; and, means for establishing at least partially a fluid connection connecting at least one of said first and second channels from a location downstream of the throttle flap corresponding thereto to said crankcase when one of said throttle flaps substantially closes the channel corresponding thereto and when said piston is disposed at a position within the range of from 90° ahead of bottom dead center to 90° after bottom dead center.