Exhaust purification control device

Abstract

To provide an exhaust emission control device capable of properly eliminating closing / fixing in a case of occurrence of the closing / fixing on a supply valve in an exhaust emission control system having two supply valves.SOLUTION: An ECU 30 includes: a fixing determination portion for determining occurrence of one-side fixing abnormality in which any one of supply valves 11, 12 has a closed / fixed state, as fixing determination to determine presence or absence of closing / fixing in the supply valve 11 and the supply valve 12; and a fixing recovery control portion for repeatedly executing normal rotation and reverse rotation of a pump 15 when the occurrence of the one-side fixing abnormality is determined, not energizing the fixed supply valve as the supply valve in the closed / fixed state and energizing the non-fixed supply valve as the supply valve not in the closed / fixed state in the normal rotation of the pump 15, and energizing the fixed supply valve and not energizing the non-fixed supply valve in the reverse rotation of the pump 15.SELECTED DRAWING: Figure 1

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