Patent ID: 7484359

Claim:
An exhaust purifying apparatus for internal combustion engine, comprising: an exhaust purifying member that is located in an exhaust passage of the internal combustion engine, wherein the exhaust purifying member traps particulate matter in exhaust gas; a fuel adding device for adding fuel to exhaust gas that passes through the exhaust purifying member; a setting section, wherein the setting section estimates a combustion rate of particulate matter in the exhaust purifying member in a state where the fuel adding device adds fuel to the exhaust gas, and wherein, based on the estimated combustion rate, the setting section sets a manner of adding fuel by the fuel adding device; wherein the setting section switches the manner of adding fuel between a continuous fuel addition, in which fuel is continuously added to exhaust gas, and an intermittent fuel addition, in which fuel is intermittently added to exhaust gas; and wherein, when it is assumed that the combustion rate of particulate matter is less than a predetermined rate, the setting section sets the manner of adding fuel to the intermittent fuel addition.