Engine with divided combustion chamber - injects fuel into auxiliary chamber only for ignition and first stage combustion

摘要

An internal combustion engine has cylinders with divided combustion chambers and spark ignition, there being a main chamber above each piston, and an auxiliary one. Fuel is injected by nozzle (8) into only the auxiliary chamber (4) during the compression stroke, between a point 120 degrees before top dead centre and top dead centre, giving a rich mixture in this chamber. The first stage of combustion takes place in this chamber, and the second one in the main chamber (5). The volume of the auxiliary chamber is at least half that of the clearance volume. At part throttle the amount of fuel injected can be such that the overall fuel/air ratio is super-stoichiometric, i.e. weak.