Patent ID: 6240724
Filing Date: 2001-06-05
Classification: F01N,F02B,F02D,F02M,Y02T

Abstract:
A control device for a direction injection engine having a catalyst provided in an exhaust passage for converting exhaust gases and an injector for injecting fuel directly into a combustion chamber, the control device comprising:a temperature state identifier for judging the temperature state of the catalyst;a water temperature sensor for detecting a temperature of engine cooling water;a load condition detector for sensing engine load condition; anda fuel injection for controlling fuel injection from the injector, the fuel injection controller performing quick light-off control operation by causing the injector to inject fuel in a one-time injection mode during a compression stroke in a specific low-load operating range of the engine when the catalyst is in its unheated state where its temperature is below its activation temperature and when the engine is in its unheated state where the temperature of the engine cooling water is below a certain temperature level, and switching the mode of fuel injection to intake-compression stroke split injection mode which includes earlier injection made during an intake stroke and later injection made during the compression stroke in a specific high-load operating range of the engine, based on judgment results of the temperature state identifier, detected result of the water temperature and sensing results of the load condition detector and for controlling the amount of the fuel injection during the quick light-off control operating such that the mean air-fuel ratio in the combustion chamber is set within a rage of 13 to 17 in the individual injection modes including the one-time injection mode in the compression stroke and the intake-compression stroke split injection mode.