EXHAUST RECIRCULATION DEVICE OF INTERNAL COMBUSTION ENGINE

摘要

PROBLEM TO BE SOLVED: To provide a technology for inhibiting insufficiency of the amount of EGR gas and inhibiting the generation of NOx in a transition condition when the operation state of an internal combustion engine is shifted from a fuel cut state to another operation state in response to an acceleration demand, which is intended for an exhaust gas recirculation device of the internal combustion engine performing EGR by selectively using a high pressure EGR means and a low pressure EGR means. SOLUTION: The exhaust gas recirculation device of the internal combustion engine performs EGR by using only the high pressure EGR when the operation state of the internal combustion engine 1 is in a HPL (High Pressure Loop) region, performs EGR by using only the low pressure EGR when the operation state of the internal combustion engine 1 is in a LPL (Low Pressure Loop) region and performs EGR by using both the high pressure EGR and the low pressure EGR when the operation state of the internal combustion engine 1 is in a MPL (Middle Pressure Loop) region. The device controls the opening degree of a low pressure EGR valve 5 to a more valve opening side than the opening degree required for NOx reduction in the shifted operation state when the operation state of the internal combustion engine 1 is shifted from the fuel cut condition to the HPL region or the MPL region in response to the acceleration demand. COPYRIGHT: (C)2008,JPO&INPIT