Patent ID: 6729315
Filing Date: 2004-05-04
Classification: F02B,F02D,F02M,Y02T

Abstract:
An exhaust gas recirculation control apparatus for an internal combustion engine, in which between an intake circuit and an exhaust circuit, a turbocharger and an exhaust gas recirculation circuit that is openable by exhaust gas recirculation switching valves are provided, comprising:an intake and exhaust bypass circuit for connecting the downstream side of a compressor to the upstream side of a turbine of said turbocharger; an intake and exhaust bypass valve having a variable opening area such that said intake and exhaust bypass circuit can be opened or closed, wherein a narrow portion is formed at the position of the intake circuit to which said exhaust gas recirculation circuit is branchingly connected; an intake bypass circuit for bypassing said narrow portion of said intake circuit; and an intake bypass valve having a variable opening such that said intake bypass circuit is openable and closeable; detecting means for detecting driving conditions of said internal combustion engine containing an EGR rate; storage means for previously storing a target EGR rate for the driving conditions of the internal combustion engine; and control means for controlling the valve opening degree of each of said intake and exhaust bypass valve and said intake bypass valve in accordance with the driving conditions of the internal combustion engine so that the EGR rate of the internal combustion engine detected by said detecting means is equal to the target EGR rate stored by said storage means.