CYLINDER DIRECT INJECTION SPARK-IGNITION INTERNAL COMBUSTION ENGINE

摘要

In a cylinder injection spark-ignition engine having a spark plug to ignite an air mixture fuel within a corresponding cylinder; a fuel injector to inject fuel into a combustion chamber; a catalytic converter interposed in an exhaust passage; and a controller, the controller being programmed to: command the fuel injector to inject a main fuel into the combustion chamber for a first time duration within at least one of a suction stroke and a compression stroke and to inject an additional fuel for a second time duration within at least one of an expansion stroke and an exhaust stroke, the controller is programmed to set a target value of a total air-fuel mixture ratio to a value of the air-fuel mixture ratio which is leaner than a stoichiometric air-fuel mixture ratio for a warm-up condition of the catalytic converter and the controller is programmed to calculate respective injection quantities (Ti1 and Ti2) of the main fuel and the additional fuel in such a manner that the total air-fuel mixture ratio based on a sum of the main fuel and the additional fuel corresponds to the set target value of the total air-fuel mixture ratio.