| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an exhaust emission control device capable of making a selective reduction type catalyst recover from an HC poisoning state before a function of the selective reduction type catalyst is significantly degraded.SOLUTION: In an exhaust emission control device in which a selective reduction type catalyst 5 and a particulate filter 10 are combined, a control device 13 is constituted to estimate an accumulation amount of particulate on the particulate filter 10 and an accumulation amount of HC on the selective reduction type catalyst 5 according to an operating state of a diesel engine 1, forcibly regenerate the particulate filter 10 when any of the accumulation amounts reaches a predetermined specified amount or more, and reset both of the accumulation amounts when the forcible regeneration is completed.</p> |
