Two-stroke internal combustion engine with crankcase scavenging

A two-stroke internal combustion engine with crankcase scavenging, with an exhaust passage controlled by a piston and at least two first transfer passages and at least one second transfer passage, each with a transfer window into a cylinder chamber and a crankcase-side window for communication between the cylinder chamber and a crankcase, the transfer windows of the first transfer passages being controlled by the upper edge of the piston, and the crankcase-side window of the second transfer passage being disposed in a region of a cylinder wall that is swept by a piston skirt of the piston, wherein for control of the second transfer passage the piston skirt of the piston is provided with a control opening in the area of the crankcase-side window of the second transfer passage, wherein a separating edge is located in at least one second transfer passage between an upper and a lower edge of said second transfer window, said separating edge dividing the second transfer window into an upper and a lower region, the distance between separating edge and cylinder axis being larger than the distance between upper edge and the cylinder axis, and wherein at least one first injector opens into the upper region of at least one second transfer passage, wherein the separating edge is shaped by a cross rib, and wherein the separating edge is arranged at right angle to the cylinder axis.

Method for operating a two-stroke internal combustion engine having at least one first injector for fuel injection into a cylinder chamber and at least one second injector for fuel injection into a crankcase chamber, wherein the first injector is activated at least at low and middle load and the second injector is activated at least at high and full load and at high engine speed.