Control system of internal combustion engine

Abstract

A control system of an internal combustion engine in which a catalyst device having oxidation ability is arranged in the exhaust system, is provided. When a temperature of the catalyst device is lower than a set temperature, the combustion temperature is made a first combustion temperature or under or is made a second combustion temperature or over, to make an amount of lower olefin in the exhaust gas smaller than that when the combustion temperature is higher than the first combustion temperature and is lower than the second combustion temperature. Therefore, an amount of lower olefin which reduces the oxidation rate of CO in the catalyst device is decreased so as to realize the quick warming-up of the catalyst device by using of the oxidation reaction heat of CO.

1 . A control system of an internal combustion engine in which a catalyst device having the oxidation ability is arranged in the exhaust system, wherein when a temperature of said catalyst device is lower than a set temperature, the combustion temperature is made a first combustion temperature or under or is made a second combustion temperature or over, to make an amount of lower olefin in the exhaust gas smaller than that when the combustion temperature is higher than said first combustion temperature and is lower than said second combustion temperature. 
     
     
         2 . A control system of an internal combustion engine according to  claim 1 , wherein an engine operating area in which the combustion temperature becomes higher than said first combustion temperature and lower than said second combustion temperature is set, and when the temperature of said catalyst device is lower than the set temperature, it is prohibited that the engine operates in said engine operating area. 
     
     
         3 . A control system of an internal combustion engine according to  claim 2 , wherein the worse the combustion becomes, the more said engine operating area is expanded to the high engine load side.