Controlled ignition I.C. engine, with spark produced in pre-combustion chamber

摘要

The i.c. engine has its fuel/air mixture ignited by a spark in a pre-combustion chamber (26) of reduced volume, fed independently with a rich mixture and linked to the main combustion chamber through a duct (32). The pre-combustion chamber is basically cylindrical in shape, with the fuel mixture inlet and spark plug electrode (22) in its upper walls, and the outlet duct in the lower one. The outlet duct has an upper section (60) which is cylindrical in shape, with its length greater than its diameter, and a lower section (62) with channels angled in different directions. The upper section joins the pre-combustion chamber via a flared or curved edge, in the latter case having a radius of curvature equal to about a fifth of the upper section's diameter. The upper section can also contain a central plug which acts as an electrode for the spark plug.