Patent ID: 8122706

Claim:
An exhaust purification system for an internal combustion engine, comprising: a first exhaust purification device requiring temperature elevation control to at least a set temperature; a second exhaust purification device arranged at an upstream side of the first exhaust purification device a first fuel feed system that feeds fuel at a position between the first exhaust purification device and the second exhaust purification device, an oxidation catalyst carried on at least one of the first exhaust purification device or an oxidation catalyst device positioned at an immediately upstream side of the first exhaust purification device; and a controller including a temperature elevation control routine which, when executed, performs the steps of: elevating the temperature in the first exhaust purification device to the at least the set temperature by feeding fuel by the first fuel feed system to be burned by the oxidation catalyst carried on the at least one of the first exhaust purification device or the oxidation catalyst device to perform the temperature elevation control in the first exhaust purification device, inhibiting the second exhaust purification device from being raised in temperature to the at least the set temperature, and in a condition that the temperature elevation control is performed in the first exhaust purification device and the oxidation catalyst is at less than the activation temperature, feeding a smaller amount of fuel from a second fuel feed system at an upstream side of the second exhaust purification device than an amount of fuel fed by the first fuel feed system, causing the smaller amount of fuel to burn by an oxidation function of the second exhaust purification device to make the temperature of the exhaust gas rise, and feeding the fuel from the first fuel feed system only after heated exhaust gas raises the oxidation catalyst in temperature to at least the activation temperature.