| 摘要 |
PROBLEM TO BE SOLVED: To prevent malfunctions, such as corrosion and clogging due to the condensation and liquefaction of the recirculating gas in a recirculation passage for recirculating the unburned HC components contained in the exhaust gas adsorbed by an HC adsorbent, inside a bypass exhaust passage. SOLUTION: An EGR pipe (recirculation passage) 72 for recirculating the unburned HC components contained in the exhaust gas adsorbed by the HC adsorbent 64 provided inside a bypass exhaust passage 56 to an intake system is made of a metal material, and the EGR pipe is brought into thermal contact with an exhaust pipe 38, to prevent the condensation and liquefaction of the recirculating gas. The EGR pipe 72 is formed there is no recirculating gas stay part thereof, even if the recirculating gas is condensed or liquefied. The inner surface of the EGR pipe is formed with a water repellent oil film, to discharge the water drops even if the recirculating gas is condensed and liquefied. |
