Patent ID: 7299623
Filing Date: 2007-11-27
Classification: F02B,F02D,Y02T

Abstract:
1. A method for controlling exhaust gas temperature to protect temperature sensitive components of a Diesel engine and associated exhaust gas aftertreatment devices during regeneration, said engine having at least one combustion chamber, at least one regenerable exhaust gas aftertreatment device disposed in an exhaust system of the engine, a turbocharger in fluid communication with said exhaust system, at least one intake valve interposed between an air intake system of the engine and said combustion chamber, at least one exhaust valve interposed between said combustion chamber and said turbocharger, and a means for controllably introducing fuel into said combustion chamber, said method comprising: determining a maximum exhaust gas temperature at which thermal damage to said exhaust valve and said regenerable exhaust gas aftertreatment device is precluded; sensing said exhaust gas temperature; controlling the operation of at least one of said intake valve and said exhaust valve in response to the sensed value of said exhaust gas temperature; maintaining the temperature of said exhaust gas at a value less than said maximum exhaust gas temperature at which thermal damage to said exhaust valve and said regenerable exhaust gas aftertreatment device is precluded; wherein said regenerable exhaust aftertreatment device comprises a lean NO determining a maximum exhaust gas temperature at which thermal damage to said turbocharger is precluded and maintaining the temperature of said exhaust gas at a value less than said maximum exhaust gas temperature at which thermal damage to said turbocharger is precluded.