| 摘要 |
<p>PURPOSE:To precisely judge a regeneration timing of a filter for combusting exhaust particulates collected by a filter. CONSTITUTION:A flow rate coefficient computing circuit 23 computes a flow rate coefficient of a filter 3 under a reference operation condition in a low load/low engine speed area set by a reference operation condition setting circuit 25. An estimated differencial pressure computing circuit 31 computes a differencial pressure under each operation condition based on the flow rate coefficient. A blow-off judgment circuit 33 judges the generation of blow-off when the difference between the estimated differencial pressure and an actual differencial pressure is a specified value or higher. A regeneration timing judgment circuit 37 judges that it is a regeneration timing of the filter 3 when the blow-off occurs as many times as are specified or more times.</p> |
