EXHAUST PURIFICATION DEVICE FOR INTERNAL COMBUSTION ENGINES

摘要

In an internal combustion engine, an exhaust purification catalyst (13), hydrocarbon feed valve (15) and particulate filter (14) are arranged in an exhaust passage. If temperature increasing control should be performed when a first NO X purification method is performed, injection of hydrocarbons for the first NO X purification method is performed with a predetermined period and injection of hydrocarbons for temperature increasing control is performed in a time period when injection of hydrocarbons for the first NO X purification method is not performed, the first NO X purification method being configured to purify NO X which is contained in the exhaust gas by injecting hydrocarbons from the hydrocarbon feed valve with the predetermined period, the temperature increasing control being configured to increase a temperature of the particulate filter to remove particulate matters trapped on the particulate filter. An amount of injection of hydrocarbons for temperature increasing control when an actual temperature of the particulate filter is low is set larger than that when the actual temperature of the particulate filter is high.