Patent ID: 6651616
Filing Date: 2003-11-25
Classification: F02B,F02D,F02M,Y02T

Abstract:
A method for operating a four-stroke reciprocating piston internal combustion engine with alternating compression ignition and spark ignition, comprising the steps of:directly injecting fuel into at least one combustion chamber, a volume of which varies cyclically; delivering fresh charge air through at least one inlet element; leading off combustion exhaust gas through at least one exhaust element; forming a partially homogenized lean basic mixture of air, fuel and retained exhaust gas at a low and medium partial load; performing compression ignition at partial load; forming a homogeneous stoichiometric mixture at higher partial load and at full load; performing spark ignition at full load; performing exhaust gas retention due to controllable valve interval and build-up of exhaust gas; performing activation injection into the retained exhaust gas; forming a signal for a change of operating mode in accordance with exhaust gas retention of the exhaust gas build-up, restriction of the fresh charge, ignition advance angle in spark ignition, quantity and timing of fuel injection and exhaust gas recirculation; changing-over between compression ignition and spark ignition by synchronous actuation of a throttle valve, an exhaust sensor flap and an exhaust gas recirculation valve; and controlling a connecting line by the exhaust gas recirculation valve, the connecting line arranged between an exhaust pipe upstream of the exhaust gas sensor flap and an intake line downstream of the throttle valve.