| 摘要 |
PURPOSE:To shorten the length of an exhaust gas return flow pipe by lowering the temperature of a return flowing exhaust gas by a method wherein an exhaust gas return flow passage provided in the wall of an air intake manifold is elongated to bypass the lower part of a distribution pipe within the manifold. CONSTITUTION:In the titled device in which a part of the exhaust gas in the exhaust pipe is extracted through the exhaust gas return flow passage 30 provided in the wall of the air intake manifold M and is introduced into a distribution chamber 21 in the manifold M, the exhaust gas return flow passage 30 is formed of an intermediate section 30b passing right below the distribution chamber 21 substantially in the horizontal direction and upper and lower flow passages 30a and 30c connected to the upstream and the downstream sides of the intermediate section 30b, respectively. The upper flow passage 30a is made to open in the upper surface of the air intake manifold M as at 31 and 31' and an exhaust gas return flow rate control valve 32 is mounted on the manifold M so as to make the openings 31 and 31' communicate with each other. Further, the lower flow passage 30c is made to rise up toward an exhaust gas outlet hole 29 from the front end of the intermediate section 30b so as to communicate with the distribution pipe 21. |
