Ignition system for internal combustion engines

Abstract

An ignition system for internal combustion engines wherein an ignition timing computer circuit starts the computation of an ignition timing in response to the detection of a predetermined angular position of the crankshaft of an internal combustion engine by an angular position detector, and an ignition device ignites the engine according to the computed ignition timing. A pressure detector detects variations of the pressure in the cylinders caused by the ignition of the engine and a retard-advance detector determines whether the angular position of the engine crankshaft corresponding to the maximum cylinder pressure agrees with the desired angular position. This retard-advance detector compensates the computation of ignition timing in the ignition timing computer circuit in accordance with its determination. In this way, the ignition timing of the engine is feedback controlled in such a manner that the pressure in the individual cylinders reaches a maximum value at the desired angular position of the crankshaft.