초록 ▼

A method is described of operating an internal combustion engine burning a fuel containing carbon and hydrogen, to provide a flame in the exhaust system to heat a catalytic converter or burn off the soot in a particulate filter trap. The method involves reducing the intake throttle opening during de

A method is described of operating an internal combustion engine burning a fuel containing carbon and hydrogen, to provide a flame in the exhaust system to heat a catalytic converter or burn off the soot in a particulate filter trap. The method involves reducing the intake throttle opening during deceleration mode below the throttle opening for the steady speed idle position to create a proportion of combustible gases in the exhaust gas stream. By ensuring at the same time the presence in the exhaust gas stream of additional air, an ignitable mixture is produced which is ignited to burn as a flame in an afterburner chamber of the exhaust system. By selecting deceleration periods to enrich the mixture excessively in this manner, adverse effects on drivability go unnoticed.

대표청구항 ▼

A method of operating an internal combustion engine burning a fuel containing carbon and hydrogen, which method comprises the steps of: a) determining when the engine is operating in a deceleration mode, b) reducing the throttle opening of the air intake to the engine only during deceleration modes

A method of operating an internal combustion engine burning a fuel containing carbon and hydrogen, which method comprises the steps of: a) determining when the engine is operating in a deceleration mode, b) reducing the throttle opening of the air intake to the engine only during deceleration modes below the throttle opening for steady speed idling to reduce the mass of air in each combustion charge when the engine is overrunning while continuing to admit fuel into the combustion chamber to result in excessively rich combustion in at least a region of the combustion charge and thereby create a proportion of combustible gases in the exhaust gas stream, c) ensuring the presence in the exhaust gas stream of additional air to mix with the combustible gases to achieve during deceleration modes an exhaust mixture having sufficiently high concentrations of combustible gases and oxygen to be ignitable, and d) igniting the mixture to burn as a flame within an afterburner chamber arranged upstream of an element of the exhaust system in order to heat the element during deceleration modes.