Patent attributes
An exhaust purifying apparatus for an internal combustion engine having a DPNR converter (26), a fuel adding device (46), and an electronic control device (50) is provided. The DPNR converter (26) is located in an exhaust passage (14) of the internal combustion engine (10). The DPNR converter (26) traps particulate matter in exhaust gas. The fuel adding device (46) adds fuel to exhaust as that passes through the DPNR converter (26). The electronic control device (50) estimates a combustion rate of particulate matter in the DPNR converter (26) in a state where the fuel adding device (46) adds fuel to the exhaust gas. Based on the estimated combustion rate, the electronic control device (50) sets a manner of adding fuel by the fuel adding device (46). As a result, the exhaust purifying apparatus suppresses excessive temperature increase of a DPNR converter (26) to which fuel is added.