EGR DEVICE

摘要

PROBLEM TO BE SOLVED: To provide an EGR device capable of securing heat exchange amount by making an EGR cooler cooling EGR gas have a water-cooling two-stage type cooler structure and of suppressing decline in temperature efficiency caused by adherence of PM in the EGR gas to inside of the cooler. SOLUTION: The EGR device is provide with an EGR passage 2 connecting an exhaust passage of an engine with an intake passage; a first water-cooling type EGR cooler 3 interposed on an exhaust gas flow upstream side of the EGR passage 2; and a second water-cooling type EGR cooler 4 interposed on the EGR passage 2 in the downstream side of the first water-cooling type EGR cooler 3. Sufficient pre-cooling of EGR gas is performed by the first water-cooling type EGR cooler 3, and deterioration of the temperature efficiency of the cooler is suppressed by suppressing PM amount moved/adhered from the EGR gas side to a cooler inner wall face by thermal diffusion by the second water-cooling type EGR cooler 4. COPYRIGHT: (C)2006,JPO&NCIPI