Method for improved internal exhaust gas recirculation in an internal combustion engine

Claim 1

In an air-compressing, self-ignition respectively spark-ignition, four-stroke internal combustion engine, having fuel injection, turbo-charging, and load-dependent internal exhaust gas recirculation which is effected, at least in certain operating ranges, by intervention in the gas change system wherein the mixture formation is essentially controlled by the high speed rotary motion of a fresh charge which is produced in an intake channel and maintained in a combustion chamber in the shape of a solid of revolution, a method of improving the internal exhaust gas recirculation, which comprises the steps of: opening an intake valve shortly after gas change-top dead center position; closing said intake valve; proceeding with compression-stroke cycle and working-operating stroke cycle accompanied by valve closing; opening an exhaust valve; pre-opening said intake valve no earlier than 30° of crank angle after gas change-bottom dead center position briefly during an exhaust stroke, with the amount of re-opening being between 15 and 30% of the maximum possible opening of said intake valve; closing said exhaust valve shortly before gas change-top dead center position; at the latest, when said exhaust valve is closed, closing said intake valve to a minimum opening; and maintaining said minimum opening until repeating said initial step of opening said intake valve shortly after gas change top dead center.