Patent attributes
An after-treatment apparatus for exhaust gas in a combustion chamber includes a discharge device with an electrode exposed to the combustion chamber and installed in at least one of members constituting the combustion chamber, an antenna installed in at least one of the members constituting the combustion chamber so as to radiate electromagnetic waves into the combustion chamber, an electromagnetic wave transmission line installed in at least one of the members constituting the combustion chamber and with one end connected to the antenna and the other end covered with an insulator or dielectric and extending to a portion, in at least one of the members constituting the combustion chamber, distant from the combustion chamber, and an electromagnetic wave generator for feeding electromagnetic waves to the electromagnetic wave transmission line. The after-treatment apparatus is configured such that discharge is generated with the electrode of the discharge device and the electromagnetic waves fed from the electromagnetic wave generator through the electromagnetic wave transmission line are radiated from the antenna, while the exhaust gas remains in the combustion chamber after the exhaust gas is produced during the explosion stroke.