Patent ID: 6470866
Filing Date: 2002-10-29
Classification: F02D,F02M

Abstract:
An internal combustion engine that operates with charge air boost and comprises:an intake system; an exhaust system comprising a tailpipe; a throttle valve for selectively restricting exhaust gas flow to the tailpipe; an exhaust gas recirculation (EGR) system for controlled recirculation of exhaust gas from the exhaust system to the intake system comprising an EGR valve having an inlet port communicated to the exhaust system upstream of the throttle valve and an outlet port communicated to the intake system; and a control for operating the EGR valve and the throttle valve, including a regulator for operating the throttle valve to partially restrict exhaust gas flow to the tailpipe to regulate the difference between pressure at the EGR valve inlet and pressure at the EGR valve outlet to a desired differential that is substantially unaffected by pressure change in the intake system and in the exhaust system.