INTERNAL COMBUSTION ENGINE HAVING TWO SPARK PLUGS FOR EACH COMBUSTION CHAMBER AND EXHAUST GAS RECIRCULATION CIRCUIT

摘要

In an internal combustion engine of the reciprocating piston type which is provided with an exhaust gas recirculation circuit to suppress the formation of NOx, each combustion chamber includes a recess formed on the bottom face of the cylinder head to have n simple shape such as hemisphere and is equipped with two spark plugs which work simultaneously. The spark gaps of the two spark plugs are positioned in the recess such that the ratio of the distance between them to the diameter of the cylinder bore is 0.45-0.67 and that the distance of each spark gap from the piston top at a crank angle of about 40.degree. after the top dead center is approximately half of the distance between the two spark gaps. - x