| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an exhaust emission control device capable of regenerating a filter at a proper frequency in an internal combustion engine in which the filter for collecting PM and an exhaust gas throttle valve are installed in an exhaust gas passage. <P>SOLUTION: A PM filter 22 for collecting PM and an exhaust gas throttle valve 18 disposed on the downstream side of the PM filter 22 are installed in the exhaust gas passage 14 of an internal combustion engine 10. An electronic control device 40 comprises, as its functions, an opening/closing control means for the exhaust gas throttle valve 18, a deposition determination means for determining the deposition of PM in the PM filter, and a prohibiting means for prohibiting the determination by the deposition determination means. The deposition determination means determines that PM is deposited in the PM filter when the differential pressure ΔP between the pressures on the upstream side and the downstream side of the PM filter 22 detected by a differential pressure sensor 34 gets to a predetermined value or more. The prohibiting means prohibits the determination by the deposition determination means while the exhaust gas throttle valve 18 is closed by the control of the opening/closing control means. <P>COPYRIGHT: (C)2008,JPO&INPIT |
