Patent ID: 6725832
Filing Date: 2004-04-27
Classification: F02B,F02D,F02M,Y02T

Abstract:
An EGR control apparatus for an internal combustion engine, comprising:an EGR valve provided to an EGR duct for connecting the intake duct and exhaust duct of an engine; an intake throttle valve and air mass sensor provided in the intake duct; feedback control means for providing feedback control to the EGR valve and intake throttle valve such that the actual air mass volume detected with said air mass sensor approximates the predetermined target air mass volume in accordance with the running condition of the engine; and valve opening limiting means for imposing restrictions so that the range of the duty assigned to either the EGR valve or the intake throttle valve is limited by means of a target duty that corresponds to the other valve and is obtained by the feedback, and that the openings of the EGR valve and intake throttle valve can be varied within specific ranges with regard to specific regions in which the valves are fully opened.