Patent application number | Description | Published |
20080289318 | Low Temperature Emission Control - A method of controlling an engine having a lean NOx trap in the exhaust is described. The method comprises during a first mode, at a first temperature, storing NOx at a lean condition and then purging stored NOx from the NOx trap at a rich condition without concurrently supplying oxygen to the trap during the purging and during a second mode, at a second, lower temperature, storing NOx at a lean condition and then purging stored NOx from the NOx, where an exothermic reaction is generated to temporarily raise the temperature of the trap by supplying oxygen and reductants with an overall rich mixture to the trap during the purging. | 11-27-2008 |
20080307851 | EXHAUST TEMPERATURE SENSOR MONITORING - A system for diagnosing an exhaust temperature sensor in an engine exhaust, the exhaust further including an emission control device, the system comprising an exhaust temperature sensor disposed in the exhaust pathway for indicating temperature; an air/fuel ratio sensor having a heater, the air/fuel ratio sensor disposed in the exhaust pathway; and a control system, the control system enabling and disabling the air/fuel ratio sensor heater based on operating conditions, the controller further adjusting fuel injection to provide a desired air-fuel ratio based on feedback from the air/fuel ratio sensor when the heater is enabled, and determining degradation of the exhaust temperature sensor based on a signal from the air/fuel ratio sensor when the heater is disabled. | 12-18-2008 |
20090120063 | Hydrocarbon Retaining System Configuration for Combustion Engine - Systems, methods, and computer readable storage media are described in which exhaust gas is routed to a hydrocarbon retaining device during starting, and purged to the engine intake manifold. Various alternative approaches are described for controlling operation and diagnosing degradation. Further, various interrelated configurations are described. | 05-14-2009 |
20090120064 | Engine Starting Control for Engine with Hydrocarbon Retaining System - Systems, methods, and computer readable storage media are described in which exhaust gas is routed to a hydrocarbon retaining device during starting, and purged to the engine intake manifold. Various alternative approaches are described for controlling operation and diagnosing degradation. Further, various interrelated configurations are described. | 05-14-2009 |
20090120065 | Hydrocarbon Retaining and Purging System for Flex-Fuel Combustion Engine - Systems, methods, and computer readable storage media are described in which exhaust gas is routed to a hydrocarbon retaining device during starting, and purged to the engine intake manifold. Various alternative approaches are described for controlling operation and diagnosing degradation. Further, various interrelated configurations are described. | 05-14-2009 |
20090120067 | Hydrocarbon Retaining System and Method - Systems, methods, and computer readable storage media are described in which exhaust gas is routed to a hydrocarbon retaining device during starting, and purged to the engine intake manifold. Various alternative approaches are described for controlling operation and diagnosing degradation. Further, various interrelated configurations are described. | 05-14-2009 |
20090120071 | Hydrocarbon Retaining System for Flex-Fuel Combustion Engine - Systems, methods, and computer readable storage media are described in which exhaust gas is routed to a hydrocarbon retaining device during starting, and purged to the engine intake manifold. Various alternative approaches are described for controlling operation and diagnosing degradation. Further, various interrelated configurations are described. | 05-14-2009 |
20100024396 | HYDROCARBON RETAINING AND PURGING SYSTEM - Method and systems are provided for operating an engine having a hydrocarbon retaining system coupled to an engine exhaust and an engine intake. One example method comprises, during an engine cold start, routing exhaust gas to the hydrocarbon retaining system to store hydrocarbons in the hydrocarbon retaining system. The method further comprises, during a first purging condition where the exhaust gas is at a first temperature, purging the hydrocarbon retaining system with at least exhaust gas, and during a second purging condition where the exhaust gas is at a second temperature, said second temperature being higher than said first temperature, mixing the exhaust gas with an amount of fresh air to form a purging gas mixture, and purging the hydrocarbon retaining system with said purging gas mixture. | 02-04-2010 |
20100223921 | HYDROCARBON RETAINING AND PURGING SYSTEM - Methods and systems are provided for operating an engine having a hydrocarbon retaining system and an emission control device coupled to an engine exhaust, the engine exhaust comprising a venturi. One example method comprises, during a storing condition, routing exhaust gas through the venturi without generating a venturi action, and then to the hydrocarbon retaining system, while bypassing the emission control device, to store hydrocarbons in the hydrocarbon retaining system, and during a purging condition, routing exhaust gas through the venturi while generating venturi action, then to the emission control device, and then to the hydrocarbon retaining system, to purge stored hydrocarbons, wherein a flow of purged hydrocarbons is drawn back to the venturi via venturi action. | 09-09-2010 |
20110061371 | HYDROCARBON AND NOx TRAP - A hydrocarbon and NOx trap and related apparatus and methods for reducing cold-start NOx emissions from an engine are provided. In one embodiment a trap includes a first, topmost layer, exposed to an exhaust gas flow path of exhaust gases from an engine, the first layer comprising a zeolite, a second layer, substantially covered by the top most layer, the second layer comprising a NOx adsorbing material and a monolithic substrate, directly supporting the second layer and indirectly supporting the first layer, the substrate providing a substantially rigid structure of the trap. | 03-17-2011 |
20110072801 | EXHAUST TREATMENT SYSTEM FOR INTERNAL COMBUSTION ENGINE - Methods and systems are provided for operating an engine including an exhaust treatment system coupled to an engine exhaust, the exhaust treatment system further coupled to an engine intake via an exhaust gas recirculation (EGR) system. One example method comprises, operating in a first mode including routing exhaust gas through the exhaust treatment system to an exhaust tailpipe; operating in a second mode including routing exhaust gas through the exhaust treatment system to an engine intake via the EGR system, and operating in a third mode including routing exhaust gas to an engine intake through the EGR system while bypassing the exhaust treatment system. | 03-31-2011 |
20110132337 | EXHAUST TREATMENT SYSTEM FOR INTERNAL COMBUSTION ENGINE - Systems and methods are provided for operating an engine exhaust system. In one example, a system comprises a first valve, and a second valve coupled to the first valve via a shaft. A first position of the shaft situates the first valve closed and the second valve open, a second position situates the second valve closed and the first valve open by a first amount, and a third position situates the second valve closed and the first valve open by a second, larger amount. | 06-09-2011 |
20110252794 | EXHAUST TREATMENT SYSTEM FOR INTERNAL COMBUSTION ENGINE - Systems and methods are provided for operating an engine exhaust system. In one example, a system comprises a first valve, and a second valve coupled to the first valve via a shaft. A first position of the shaft situates the first valve closed and the second valve open, a second position situates the second valve closed and the first valve open by a first amount, and a third position situates the second valve closed and the first valve open by a second, larger amount. | 10-20-2011 |
20120137659 | Hydrocarbon Retaining System Configuration for Combustion Engine - Systems, methods, and computer readable storage media are described in which exhaust gas is routed to a hydrocarbon retaining device during starting, and purged to the engine intake manifold. Various alternative approaches are described for controlling operation and diagnosing degradation. Further, various interrelated configurations are described. | 06-07-2012 |
20120204544 | HYDROCARBON RETAINING AND PURGING SYSTEM - Methods and systems are provided for operating an engine having a hydrocarbon retaining system and an emission control device coupled to an engine exhaust, the engine exhaust comprising a venturi. One example method comprises, during a storing condition, routing exhaust gas through the venturi without generating a venturi action, and then to the hydrocarbon retaining system, while bypassing the emission control device, to store hydrocarbons in the hydrocarbon retaining system, and during a purging condition, routing exhaust gas through the venturi while generating venturi action, then to the emission control device, and then to the hydrocarbon retaining system, to purge stored hydrocarbons, wherein a flow of purged hydrocarbons is drawn back to the venturi via venturi action. | 08-16-2012 |
20130202495 | HYDROCARBON TRAP FOR REDUCING COLD-START ENGINE EMISSIONS - A hydrocarbon trap is provided for reducing cold-start hydrocarbon emissions. The trap contains an acidic absorption material for improving absorption of low molecular weight hydrocarbons. The acidic absorption materials may be used either alone or in combination with zeolites which are integrated into and/or supported on a monolithic substrate. The hydrocarbon trap may be positioned in the exhaust gas passage of a vehicle such that hydrocarbons are adsorbed on the trap and stored until the engine and exhaust reach a sufficient temperature for desorption. | 08-08-2013 |
20130247544 | HYDROCARBON RETAINING AND PURGING SYSTEM FOR FLEX-FUEL COMBUSTION ENGINE - Systems, methods, and computer readable storage media are described in which exhaust gas is routed to a hydrocarbon retaining device during starting, and purged to the engine intake manifold. Various alternative approaches are described for controlling operation and diagnosing degradation. Further, various interrelated configurations are described. | 09-26-2013 |
20130287659 | COMBINED HYDROCARBON TRAP AND CATALYST - A combined hydrocarbon trap/oxidation catalyst system is provided for reducing cold-start hydrocarbon emissions. The hydrocarbon trap includes a monolithic substrate containing zeolite and a catalyst including a mixture of nickel and copper which is impregnated into or washcoated onto the substrate. The hydrocarbon trap may be positioned in the exhaust gas passage of a vehicle such that hydrocarbons are adsorbed on the trap and stored until the engine and exhaust reach a sufficient temperature for desorption and oxidation of the hydrocarbons. | 10-31-2013 |
20140044625 | HYDROCARBON TRAP HAVING IMPROVED ADSORPTION CAPACITY - A hydrocarbon trap is provided for reducing cold-start hydrocarbon emissions. The trap is formed by extruding from about 60 to 80% by weight zeolite and from about 20 to 40% by weight of a binder to form an extruded zeolite monolith. A three-way catalyst and an oxygen storage capacity material may also be included in the trap. The hydrocarbon trap contains from about 5.0 to 8.0 g/in. | 02-13-2014 |