| 摘要 |
<p>An exhaust pipe for a vehicle-mounted engine. The outer end (132C) of an inner pipe (131) inserted in an outer pipe (110) is in contact at a first position with the inner peripheral surface of an outer pipe (110), the outer pipe (110) is in contact with the inner pipe (131) at a second position different from the first position, and as a result, an expansion chamber (135) is formed between the inner pipe (131) and the outer pipe (110). The inner pipe (131) has communication holes for interconnecting the inside of the inner pipe (131) and the expansion chamber (135). Thus a silencer is formed. An exhaust purification catalyst (21) is installed in the outer pipe (110) so as to be adjacent to the expansion chamber (135). On the inner peripheral surface of the outer pipe (110), there is formed a weir (116) between the outer end (132C) of the inner pipe (131) and the exhaust emission control catalyst (21), and the weir (116) stops the flow of condensed water. Consequently, deterioration of the purification function of the exhaust purification catalyst caused by contact of the condensed water, which is produced when the exhaust gas is cooled, with the exhaust purification catalyst in the exhaust pipe (110) can be suppressed.</p> |
