| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an exhaust emission control device for an internal combustion engine accurately detecting failure of DPF in regard to an exhaust emission purifier measuring a PM amount passing through the DPF to detect failure of the DPF. <P>SOLUTION: After executing a process (S30) of increasing a PM amount flowing into the DPF, an amount of soot having passed through the DPF is measured by a soot sensor disposed downstream of the DPF (S40), a threshold for failure detection is calculated (S60) based on an estimate (S50) of a PM deposit amount in the DPF, degrees of the soot sensor measured value and the threshold are determined (S70), and it is determined that the DPF is broken when the soot sensor measured value is the same or more than the threshold (S80). By proceeding (S20) to failure detection even when an elapsed time or a traveling distance from prior failure determination exceeds predetermined values, too much elongation of a blank period of DPF failure detection is avoided. <P>COPYRIGHT: (C)2010,JPO&INPIT |
