| 摘要 |
A cooling system for an internal combustion engine 1 comprises a coolant circuit through which coolant is circulated by a pump 4, an electronically controlled flow control valve 2 to control the flow of coolant flowing through the engine, and an exhaust gas cooler 5 forming part of an exhaust recirculation system provided to recirculate exhaust gas from an exhaust outlet of the engine to an air inlet of the engine. The exhaust gas cooler is arranged to receive a supply of coolant from a position located upstream of the electronically controlled flow control valve such that, when the electronically controlled flow control valve is operated to restrict the flow of coolant through the engine, the flow through the exhaust gas cooler is automatically increased. Preferably, the electronically controlled flow control valve is able to control the cooling of the engine irrespective of the speed at which the pump used to urge coolant to flow into the engine is rotated. The electronically controlled flow control valve may either be located at an outlet from the engine or between the pump and the engine. Preferably, the engine comprises a cylinder block and a cylinder head which include coolant passages. The engine cylinder block and engine cylinder head may each have an independent coolant flow path therethrough. |
