Ford Global Technolgoies, LLC

Ford Motor Company Limited

Other

Joseph Richard Asik

Garth Michael Meyer

Jeffrey Scott Hepburn

Richard Walter Anderson

Aladar O Simko

Daniel Lawrence Meyer

Xiaoguo Tang

Rogelio G Samson

Mitsugu Hanabusa

Jody M Kirsch

Richard C Ronzi

A system and method are provided for closed-loop monitoring of temperature within a vehicle emission control device to control air-fuel ratio (AFR) and corresponding production of exotherm to accurately maintain a desired temperature range. A temperature sensor is positioned within the emission control device to provide a direct measurement of temperature within the device. Inlet temperature can be either directly measured or estimated using a temperature model. Actual temperature within the device is estimated as a function of the inlet and measured temperatures. The estimated actual temperature is used to modify the AFR in the exhaust gases flowing through the emission control device.

Closed-loop temperature control for an emission control device

A method and system are provided for determining a present value representative of the quantity of oxygen that is stored in an emission control device receiving exhaust gas generated by an internal combustion engine, as well as a present value for the maximum capacity of the device to store a selected constituent gas of the exhaust gas. The resulting values are advantageously used for adaption of predetermined values for controlling device fill and purge times when operating in an open-loop control mode, whereby open-loop device operation is optimized to reflect changes in device operating conditions.

Method for quantifying oxygen stored in a vehicle emission control device

A method and system for optimizing the purging of a constituent gas of a vehicle engine's generated exhaust gas from an emission control device is disclosed wherein the amplitude of the output signal generated by a downstream switching oxygen sensor, and the time response of the sensor, is used to iteratively adjust a current purge time to obtain an optimized purge time.

Method and system for optimizing purge of exhaust gas constituent stored in an emission control device

A system and method for optimizing the regeneration cycle of an emission control device, such as a lean NO trap, is disclosed wherein the device is filled to a predetermined fraction of its existing capacity and is then completely emptied during a device purge. As device capacity is substantially reduced, as indicated by the actual fill time becoming equal to or less than a predetermined minimum fill time, a device desulfation event is performed to attempt to restore device capacity. A programmed computer controls the fill and purge times based on the amplitude of the voltage of a switching-type oxygen sensor and the time response of the sensor. The frequency of the purge, which ideally is directly related to the device capacity depletion rate, is controlled so that the device is not filled beyond the storage capacity limit.

Method and system for controlling a regeneration cycle of an emission control device

A method of optimizing vehicle emissions during lean engine operation is disclosed wherein an emission control device receiving engine exhaust gases is filled with one or more constituent gases of the exhaust gas to a predetermined fraction of the device storage capacity, and is then completely emptied during a subsequent purge. As the device storage capacity is substantially reduced, as indicated by an actual fill time becoming equal to or less than a predetermined minimum fill time, a device regeneration cycle is performed to attempt to restore device capacity. A programmed computer controls the fill and purge times based on the amplitude of the voltage of a switching-type oxygen sensor and the time response of the sensor. The frequency of the purge, which ideally is directly related to the device capacity depletion rate, is controlled so that the device is not filled beyond its storage capacity limit.

Method and system for controlling an emission control device based on depletion of device storage capacity

A method and system are provided for adaptive control of a purge time and a fill time for an emission control device used to reduce emission of a selected constituent gas, such NO , of an engine's generated exhaust gas, with optimization and adapting of stored values to reflect changes in device operating conditions. The invention determines a present value representative of the quantity of oxygen stored in the device, as well as a present value for the maximum device NO -storage capacity to provide real-time adjustment of purge and fill time to achieve optimum overall operation of the device. The invention also periodically determines actual fill times which corresponding to optimal fill times to generate adaptive values for use during normal open-loop control.

Method and system for controlling storage and release of exhaust gas constituents in an emission control device

Method and system for optimizing open-loop fill and purge times for an emission control device

A method and apparatus for desulfating a NO,trap is proposed wherein the SO,purge temperature is achieved by modulating the amplitude of the A/F of the mixture supplied to the engine thereby storing oxygen in the trap during lean engine cylinder events and generating the required exotherm during rich engine cylinder events.

Method and apparatus for desulfating a NOx trap

A system and method for desulfating an NO.sub.x trap utilizes a closed loop control of the air-to-fuel (A/F) ratio to accurately maintain a precise A/F ratio during desulfation. An oxygen sensor is positioned in the middle of the trap to provide an actual A/F ratio measurement, which is subsequently compared to a target A/F ratio to generate a correction signal to adjust operation of the engine's fuel injector(s). The trap oxygen sensor can also be used to adaptively update engine state conditions for a more precise switch-over to a trap regeneration phase.

Closed loop control for desulfating a NO.sub.x trap

A method and apparatus for desulfating a NO.sub.x trap is proposed wherein the SO.sub.x purge temperature is achieved by modulating the amplitude of the A/F of the mixture supplied to the engine thereby storing oxygen in the trap during lean engine cylinder events and generating the required exotherm during rich engine cylinder events.

Method and apparatus for desulfating a no.sub.x trap

A method and system for determining and controlling air/fuel ratio during engine cold start operation relies on applying a monotonically decreasing fuel pulse width modulation to the engine and synchronously measuring the effect of the modulation on related engine event periods. This effect is utilized in estimating air/fuel ratio, which is then compared to the desired air/fuel ratio. The difference between the estimated air/fuel ratio and the desired air/fuel ratio is used in controlling the air/fuel ratio to the desired air/fuel ratio.

Method and system for determining and controlling A/F ratio during cold

A method and apparatus for desulfating a NO.sub.x trap is proposed wherein half of the engine cylinders are operated at a rich air/fuel ratio and half are operated at a lean A/F during the desulfation process. The two exhaust gas streams, the rich stream and the lean stream, are physically or chemically separated until they enter the NO.sub.x trap. A catalyzed exothermic chemical reaction is then generated in the trap. The resulting temperature increase is sufficient to remove SOX from the trap. During desulfation spark advance is adjusted to minimize event time imbalance.

Method and apparatus for desulfating a NO.sub.x trap

A method and system for controlling combustion stability for a lean-burn engine having a plurality of cylinders including a plurality of cylinder pairs utilizes a speed sensor for sensing an engine speed and generating a corresponding temperature signal and an air flow sensor for sensing a cylinder air mass and generating a corresponding air mass signal. An average event time for each of the plurality of cylinders is determined, as well as an instantaneous variation in event times between each of the plurality of cylinder pairs. An actual level of engine roughness is determined based on the variation in instantaneous event times from the average event times. A desired level of engine roughness is determined based on the speed signal, the air mass signal, and a desired air/fuel ratio. The engine is then controlled based on the actual level of engine roughness and the desired level of engine roughness so as to directly control the combustion stability of the engine and to indirectly control the air/fuel ratio of the engine.

Method and system for controlling combustion stability for lean-burn

A method and system for determining and controlling air/fuel ratio during lean engine operation relies on applying a small fuel pulse width modulation to the engine and synchronously measuring the effect of the modulation on related engine event periods. This effect is utilized in estimating air/fuel ratio, which is then compared to the desired air/fuel ratio. The difference between the estimated air/fuel ratio and the desired air/fuel ratio is used in controlling the air/fuel ratio to the desired air/fuel ratio.

Method and system for determining and controlling a/f ratio in lean

A spark plug for an ignition system has a ring gap between two electrodes. A first electrode has a ring shape defining a central opening. A second electrode is positioned within the central opening of the first electrode. An insulating material is positioned between the first and second electrodes so as to provide a surface for a spark path between the first and second electrodes. The insulating material is spaced from the electrode so as to provide therebetween an air gap for increased sparking.

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Bloomfield Hills, MI, United States of America

Joseph Richard Asik