| 摘要 |
An exhaust gas recirculation (EGR) system is provided for an internal combustion engine (10) having a combustion air intake circuit (12), an exhaust manifold, and an exhaust circuit for communicating engine exhaust to the environment. The EGR system includes an air-to-gas EGR cooler (34), an air supply conduit for supplying inlet air to the EGR cooler (34), an EGR supply conduit for communicating exhaust from the exhaust circuit to the EGR cooler (34), and an EGR outlet conduit communicating cooled EGR from the EGR cooler (34 to the intake circuit. The EGR system also includes a venturi unit (44) in the exhaust circuit, and an air outlet conduit communicating heated air from the EGR cooler (34) to the venturi unit (44). Flow of exhaust through the venturi (44) creates a pressure which draws cooling air through the EGR cooler (34). A valve (48) controls flow through the outlet conduit as a function of a sensed temperature in the intake circuit. |
