EXHAUST GAS PURIFICATION DEVICE FOR INTERNAL COMBUSTION ENGINE

摘要

The purpose of the present invention is to improve the exhaust gas purification rate by accurately controlling the air-fuel ratio even in an internal combustion engine that uses alcohol-containing fuel. This exhaust gas purification device for an internal combustion engine is characterized by being provided with an exhaust gas purification catalyst which is disposed in an exhaust gas passage of the internal combustion engine, an air-fuel ratio sensor which is installed upstream from the exhaust gas purification catalyst and detects the air-fuel ratio of exhaust gas discharged from the internal combustion engine, an air-fuel ratio feedback control means which feedback-controls the air-fuel ratio of the internal combustion engine on the basis of the output of the air-fuel ratio sensor, and a sensor output correction means which corrects the deviation of the output of the air-fuel ratio sensor, the deviation being caused by a component contained in the exhaust gas, the sensor output correction means being configured so as to correct the deviation of the output of the air-fuel ratio sensor using the amount of deviation to the lean side of the output of the air-fuel ratio sensor according to the amount and/or percentage of aldehyde contained in the exhaust gas.