| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an exhaust gas cooling system for an internal combustion engine having an exhaust gas cooling structure, the system materializing suitable suppression of a reduction in the temperature of exhaust gas during low-load operation of the internal combustion engine.SOLUTION: There is provided the exhaust gas cooling system for the internal combustion engine having an exhaust emission control catalyst arranged in an exhaust pipe downstream of a collected part of a plurality of exhaust branch pipes corresponding to a plurality of cylinders of the internal combustion engine. The exhaust gas cooling system includes a cooling part for cooling an exhaust passage upstream of the collected part of the exhaust branch pipes, and a heat transfer inhibiting part configured in association with the plurality of exhaust branch pipes so as to inhibit heat transmission from the exhaust branch pipes downstream of positions to be cooled by the cooling part to the cooling part, the heat transfer inhibiting part having heat transmission inhibiting capability set in such a manner that as the temperature of the exhaust branch pipe is higher when the internal combustion engine is in a predetermined low-load operating condition, the inhibiting capability corresponding to the exhaust branch pipe is higher.</p> |
