Particulate matter processing apparatus (as amended)

Abstract

An excessively large electric current is suppressed from flowing to an electrode. A particulate matter processing apparatus in which a processing part with an electrode installed therein is arranged in an exhaust passage of an internal combustion engine, wherein particulate matter is caused to aggregate by generating a potential difference between the electrode and the processing part, is provided with a power supply that is connected to the electrode and applies a voltage thereto, a current detection device that detects an electric current which passes through the electrode, an air fuel ratio detection device that detects or estimates an air fuel ratio of an exhaust gas which flows through the exhaust passage, and a voltage control device that makes the voltage applied to the electrode from the power supply smaller in cases where the air fuel ratio detected by the air fuel ratio detection device is a rich air fuel ratio, than in cases where it is a stoichiometric air fuel ratio or a lean air fuel ratio.

Dependencies are inferred from the claim text.