Patent ID: 7934371

Claim:
An internal combustion engine system including an internal combustion engine with a purification catalyst provided in an exhaust line thereof, the internal combustion engine system comprising: a fuel injection module configured to inject a fuel into the internal combustion engine; an exhaust recirculation module arranged to recirculate part of exhaust of the internal combustion engine into a gas intake line of the internal combustion engine; a temperature-reflecting physical quantity detector constructed to measure a temperature-reflecting physical quantity representing temperature of the internal combustion engine; and a temperature increase controller configured to, upon satisfaction of a preset condition for preventing a temperature increase of the purification catalyst, when the temperature of the internal combustion engine represented by the temperature-reflecting physical quantity measured by the temperature-reflecting physical quantity detector is not lower than a preset reference temperature, perform a first control of controlling the exhaust recirculation module to recirculate the part of the exhaust of the internal combustion engine into the gas intake line and thereby prevent the temperature increase of the purification catalyst, and when the temperature of the internal combustion engine represented by the temperature-reflecting physical quantity measured by the temperature-reflecting physical quantity detector is lower than the preset reference temperature, perform a second control of controlling the fuel injection module to increment an amount of the fuel to be injected into the internal combustion engine and thereby prevent the temperature increase of the purification catalyst.