Patent ID: 8141348
Filing Date: 2012-03-27
Classification: F01N,Y02T

Abstract:
1. A method of controlling dosing of a hydrocarbon fuel into exhaust gases from an internal combustion engine to facilitate the regeneration of a particulate filter having particulates captured therein, the internal combustion engine having a number of cylinders for internal combustion and producing exhaust gases, an exhaust gas system constructed and arranged to flow exhaust gases therethrough, the exhaust system comprising an oxidation catalyst upstream of a particulate filter constructed and arranged to capture particulates in the exhaust gases, and a doser for injecting hydrocarbons into exhaust gases, the method comprising: controlling the dosing of a hydrocarbon fuel into the exhaust gases in the exhaust gas system upstream of the particulate filter to oxidize particulates trapped in the particulate filter, comprising determining if the exhaust gas temperature into the oxidation catalyst upstream of the particulate filter is above the light-off temperature for the catalyst, and if so beginning or continuing to dose a hydrocarbon fuel into the exhaust gases upstream of the particulate filter, and if not, determining if the oxidation catalyst is still warm enough to oxidize the dosing fuel, and if so, beginning or continuing to dose the hydrocarbon fuel into the exhaust gas of the exhaust gas system, and if the oxidation catalyst is not still warm enough to oxidize the dosing fuel then stopping the dosing; wherein determining if the oxidation catalyst is still warm enough to oxidize the dosing fuel comprises determining if an exhaust gas outlet temperature of the oxidation catalyst is at or above a first temperature and measuring a time period since the outlet temperature was at or above the first temperature.