| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an exhaust emission control device capable of preventing accumulation of deposits in a pressure introduction pipe without reducing measurement accuracy of pressure on an upstream side of a particulate filter. <P>SOLUTION: A differential pressure detector 27 detects differential pressure between pressure introduced from an exhaust pipe 24A via an upstream side pressure introduction pipe 28 and pressure introduced from an exhaust pipe 24B via an upstream side pressure introduction pipe 29, namely, pressure difference between an upstream side and a downstream side of the particulate filter 25. A straight part at an inlet 282 side of the upstream side pressure introduction pipe 28 is covered by metal heat insulating pipe 31, and a leading end 311 and a terminal end 312 of the heat insulating pipe 31 are joined to an outer circumference surface of the straight part 283 and fixed by caulking or blazing. The heat insulating pipe 31 is fixed to the upstream side pressure introduction pipe 28 to form an air gap 32 between the heat insulating pipe 31 and the straight part of the upstream side pressure introduction pipe 28. Air is shut in the air gap 32. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
