Patent ID: 7171925
Filing Date: 2007-02-06
Classification: F01L,F02B,F02D,F02P

Abstract:
1. A method for reversing the direction of rotation of a two-stroke engine whose rotational speed and crank mechanism position are sensed using a suitable sensor system, in which method, in order to reverse the direction of rotation of the engine, the ignition and/or the fuel supply is first switched off, and upon a subsequent coasting of the engine, a targeted early ignition is set when a specific limiting rotational speed is undershot and after, if appropriate, the fuel supply has been resumed; wherein early ignition reverses the direction of rotation of the engine, and the fuel supply and ignition are subsequently controlled in accordance with the reversed direction of rotation; wherein a single sensor interacts with an incremental transducer having a specific number of transducer segments distributed uniformly over a circumference, and the incremental transducer has a gap; and the instantaneous angular speed of the crank mechanism over the circumference is determined using the transducer segments and the gap in order to determine the crank mechanism position; in which method, when the engine coasts, fluctuations in the angular speed of the crank mechanism, which fluctuations are caused by compression and expansion phases of at least one combustion chamber of the engine, are sensed during one rotation of the engine and are assigned to a specific transducer segment, and the direction of rotation of the engine is determined from the relative angular position of this transducer segment with respect to the gap.