Otto-cycle internal combustion engine

摘要

In the ignition system of the internal combustion engine, a preignition control circuit is further provided. The preignition control circuit includes a high voltage generator which supplies a high voltage to the spark plug to produce a preignition spark between the electrodes of the spark plug. The preignition spark is timed to appear as the engine nearly concludes its suction stroke so that radicals are produced from the air-fuel mixture around the electrodes thereby to ensure reliable ignition and complete burning of the air-fuel mixture.