Patent ID: 6428754
Filing Date: 2002-08-06
Classification: B01D,Y02T

Abstract:
Exhaust gas treatment system for treating the exhaust gases of an internal combustion engine comprising:an exhaust pipe; a catalytic converter having an inlet and an outlet connected in said exhaust pipe for treating exhaust gases passing through said exhaust pipe; an igniter in said exhaust pipe having an inlet and an outlet, the inlet of said catalytic converter being connected to the outlet of said igniter, said igniter including catalyst material for raising the temperature of the exhaust gases passing through said igniter to a temperature sufficient to ignite said catalytic converter; a bypass passage extending around said igniter to communicate exhaust gases directly to said catalytic converter bypassing said igniter; a control valve in said exhaust pipe shiftable from a first position in which a first portion of said exhaust gases are directed through said bypass passage and a second portion of the exhaust gases are directed through said igniter, said first portion being greater than said second portion, to a second position in which substantially all of the exhaust gases are directed through said bypass passage; and a controller responsive to the temperature within said catalytic converter for shifting said control valve between said first and second positions, said controller switching said valve to said first position after engine start but before ignition of said catalytic converter and to said second position after ignition of said catalytic converter.