Patent ID: 6378297
Filing Date: 2002-04-30
Classification: F01N,F02B,F02D,F02M,Y02T

Abstract:
An internal combustion engine having a combustion chamber and an exhaust passage, said engine comprising:fuel injection means for injecting an auxiliary fuel into the combustion chamber, in addition to a main fuel, in accordance with necessity to produce unburned hydrocarbons; an exhaust gas after-treatment device arranged in the exhaust passage, a temperature of said exhaust gas after-treatment device rising when a temperature of exhaust gas rises and rising when unburned hydrocarbons are supplied to said exhaust gas after-treatment device; and injection control means for retarding an injection timing of the main fuel when the temperature of the exhaust gas after-treatment device should rise, as compared with the case where the temperature of the exhaust gas after-treatment device should not rise, at least two injection patterns, which are different in at least one of an amount of retardation of the injection timing of the main fuel and injection timing of the auxiliary fuel, being determined in advance to raise the temperature of the exhaust gas after-treatment device, said injection control means cyclically choosing any one of the injection patterns in accordance with a demand for a temperature raising rate of the exhaust gas after-treatment device and injecting fuel in accordance with the chosen injection pattern when the temperature of the exhaust gas after-treatment device should rise.