Exhaust gas recirculation system

摘要

A recirculation exhaust gas extracted from the exhaust passage of an internal combustion engine and flowing through a recirculation passage. A recirculation control valve (6) controls the flow of the recirculation exhaust gas in the recirculation passage. A recirculation pipe (7) forming the recirculation passage has a hot or contact section (7c, 7e) extending near and along an exhaust manifold (1). The recirculation pipe (7) and the exhaust manifold (1) are covered with a heat-insulation cover (10). The drop of the temperature of the recirculation exhaust gas flowing through the recirculation passage is suppressed and the deposition of deposits including carbon in the recirculation control valve (6) is suppressed.