Internal combustion engine exhaust gas after-burning system

Claim 1

An exhaust gas after-burning system of an internal combustion engine, the engine having a plurality of exhaust ports and the system including: a thermal reactor communicating with the plurality of exhaust ports and having an after-burning chamber wherein a spark plug is provided to ignite a combustible mixture for after-burning unburned noxious compounds contained in the exhaust gas received from the exhaust ports; a secondary air injection nozzle disposed in the after-burning chamber for injecting secondary air thereinto and connected through a heatable chamber to a secondary air source; a first conduit connecting the after-burning chamber to the plurality of exhaust ports to receive exhaust gas for feeding into the after-burning chamber; and a second conduit connected at one end to the first conduit to receive a portion of the exhaust gas; a fuel injection nozzle disposed in the second conduit for spraying additional fuel to form additional fuel mist within the exhaust gas therein; and a fuel vaporizer connected to the other end of the second conduit and disposed in the after-burning chamber to distribute the additional fuel mist in the after-burning chamber for instant vaporizing.