Abstract: An apparatus for measuring at least one of temperature and pressure within a cylinder of an internal combustion engine can include an engine valve and a sensor. The internal combustion engine can include a valvetrain having rocker arm assembly, a camshaft, a valve, and a hydraulic lash adjuster. The engine valve can have a valve head and a valve stem extending from the valve head in an axial direction. The valve head can have a valve face configured to be in pressure communication with an engine cylinder. The valve stem can have an outer surface with a cylindrical portion and a variably-shaped portion. The variably-shaped portion can define a target detectable by the sensor and the sensor can be installed adjacent to the target. Alternatively, the sensor can be positioned to detect a level of force at some point along the valvetrain.

Abstract: A valvetrain includes a rocker arm assembly having a rocker arm and an electromagnetic latch assembly. A magnet of the latch assembly is housed within a chamber formed by the rocker arm. The chamber may be a retrofit hydraulic chamber. The magnet may be an electromagnet or a permanent magnet. A flux shifting bi-stable latch provides a sufficiently compact design. Isolation of the magnet within the rocker arm chamber may provide protection from metal particles carried by oil in an operating environment for the rocker arm assembly.

Abstract: An internal combustion engine includes a cam-actuated rocker arm assembly with a solenoid-actuated latch that provides for cylinder deactivation or variable valve actuation. The solenoid is in a position where its inductance varies significantly in relation to the position of a latch pin as it translates between latching and non-latching configurations. A sensor is positioned to monitor a current or a voltage in a circuit that includes the solenoid. The sensor data is analyzed to provide diagnostic information relating to the operation of the rocker arm assembly.

Abstract: A valvetrain for an internal combustion engine of the type that has a combustion chamber, a moveable valve having a seat formed in the combustion chamber, and a camshaft includes a rocker arm assembly, a pivot providing a fulcrum for a rocker arm of the rocker arm assembly, and a latch assembly. An electrical device mounted to the rocker arm assembly receives power or communicates through a circuit that includes an electrical connection formed by abutment between surfaces of two distinct parts. The rocker arm assembly is operative to move one of the two abutting surfaces relative to the other in response to actuation of the cam follower. Forming an electrical connection through abutting surfaces that are free to undergo relative motion may reduce or eliminate the need to run wires to a mobile portion of the rocker arm assembly.

Abstract: A switching rocker arm assembly constructed in accordance to one example of the present teachings includes an outer arm, an inner arm, a bearing axle and a pivot axle. The outer arm can have a first outer side arm and a second outer side arm. The outer arm can define outer bores. The inner arm can have a first inner side arm and a second inner side arm. The inner arm can be disposed between the first and second outer side arms. The inner arm can define inner bores. The bearing axle can support a bearing. One of the bearing axle and pivot axle comprises (i) a central axle body having a central centerline, (ii) a first axle end body having a first centerline and (iii) a second axle end body having a second centerline. The central centerline is offset from at least one of the first and second centerlines.

Abstract: An internal combustion engine has a valvetrain that includes a rocker arm assembly on which is mounted an electronic device and at least a part of a generator. The generator converts some of the mechanical energy that is transmitted through the rocker arm assemblies into electricity. That electricity may be used to power an electric latch, a transmitter, or another type of rocker arm assembly-mounted electrical device. Various generator configurations are described. In some configurations, the generator is piezoelectric. In other configurations, the generator is electromagnetic. In some configurations, the generator is driven by force transmitted by the rocker arm assembly from a cam. In some configurations, the generator is driven by vibrations.

Abstract: A valvetrain includes a rocker arm assembly having an electromagnetic latch housed in a chamber formed by a rocker arm. The chamber may be a retrofit hydraulic chamber. A flux shifting bi-stable latch provides a sufficiently compact design. Isolation of the magnetic elements within the rocker arm chamber may provide protection from metal particles carried by oil in an operating environment for the rocker arm assembly. Wiring connections to the rocker arms may be made through spring posts on the rocker arms. Connection to the rocker arms may be made with springs that can endure the rapid motion induced by the rocker arms. A wiring harness for the rocker arms may attach to hydraulic lash adjusters of the rocker arm assemblies. The rocker arm assemblies and their wiring may be formed into a unitary module that facilitates installation.

Abstract: A system and method for cylinder deactivation in a multi-cylinder diesel engine comprises pumping air in to an intake manifold of the diesel engine using a turbocharger. Air is pumped in to the intake manifold using an intake air assisting device. And, fuel injection is selectively deactivated to at least one of the cylinders in the diesel engine. An intake valve and an exhaust valve is selectively deactivated for the at least one of the cylinders of the diesel engine.

Abstract: A switching rocker arm assembly constructed in accordance to one example of the present disclosure can include an outer arm, an inner arm, a pivot axle, a bearing axle, a first torsional bearing axle spring and a second torsional bearing axle spring. The outer arm can have a first outer side arm and a second outer side arm. The outer arm can further include first and second torsional spring mounts. The inner arm can be disposed between the first and second outer side arms. The pivot axle can support the inner and outer arm for relative pivotal movement therearound. The bearing axle can support a bearing. The first torsional bearing axle spring can be mounted around the first torsional spring mount and have a first end engaged to the bearing axle and a second end engaged to the outer arm. The first end extends inboard relative to the second end.

Abstract: An apparatus for measuring at least one of temperature and pressure within a cylinder of an internal combustion engine can include an engine valve and a sensor. The internal combustion engine can include a valvetrain having rocker arm assembly, a camshaft, a valve, and a hydraulic lash adjuster. The engine valve can have a valve head and a valve stem extending from the valve head in an axial direction. The valve head can have a valve face configured to be in pressure communication with an engine cylinder. The valve stem can have an outer surface with a cylindrical portion and a variably-shaped portion. The variably-shaped portion can define a target detectable by the sensor and the sensor can be installed adjacent to the target. Alternatively, the sensor can be positioned to detect a level of force at some point along the valvetrain.

Abstract: An internal combustion engine has a cylinder head mounted to an engine block that at least partially forms a plurality of cylinder combustion chambers. The cylinder head has multiple intake ports and multiple exhaust ports. Engine valves regulate the passage of gas into and out of the combustion chamber. Cam-operated engine valves are mechanically coupled to a rotating cam directly or through one or more of a variety of components that assist in transforming the rotational kinetic energy of the cam to linear motion of the engine valves. One of the exhaust valves and one of the intake valves are mechanically coupled to the cam. Electrohydraulic actuators actuate separate intake and exhaust valves of a particular cylinder. The electrohydraulic actuators are in fluid communication with a high pressure fluid source.

Abstract: An internal combustion engine has a cylinder head mounted to an engine block that at least partially forms a plurality of cylinder combustion chambers. The cylinder head has multiple intake ports and multiple exhaust ports. Engine valves regulate the passage of gas into and out of the combustion chamber. Cam-operated engine valves are mechanically coupled to a rotating cam directly or through one or more of a variety of components that assist in transforming the rotational kinetic energy of the cam to linear motion of the engine valves. One of the exhaust valves and one of the intake valves are mechanically coupled to the cam. Electrohydraulic actuators actuate separate intake and exhaust valves of a particular cylinder. The electrohydraulic actuators are in fluid communication with a high pressure fluid source.

Abstract: An exhaust aftertreatment system having a NOX absorber-catalyst and an ammonia-SCR reactor. During regenerations, the NOX absorber-catalyst generates ammonia. The ammonia-SCR reactor captures this ammonia and later uses it to reduce NOX. A Venturi is provided in an exhaust conduit connecting the NOX absorber-catalyst to the ammonia-SCR reactor. The Venturi draws sufficient air to keep the ammonia-SCR reactor under lean conditions throughout the NOX absorber-catalyst regenerations. Maintaining lean conditions for the ammonia-SCR reactor in this manner mitigates poisoning of the ammonia-SCR reactor by hydrocarbons slipping from the NOX absorber-catalyst during the regenerations. Mitigating this poisoning improves the performance of the exhaust aftertreatment system and reduce the loss of useful ammonia to oxidation.

Abstract: Desulfation methods for an exhaust treatment system having a fuel reformer configured upstream of a LNT. Reductant is injected upstream of the fuel reformer. The reductant reacts within the reformer to generate heat, but the system is configured for some reductant to breakthrough and react in the LNT to generate further heat. This configuration allows the LNT to operate at temperatures higher the than first device and facilitates independent control of the LNT and first device temperatures.

Abstract: A diesel exhaust aftertreatment system comprises an LNT within an exhaust line. A low thermal mass DPF and a low thermal mass fuel reformer are configured within the exhaust line upstream from the LNT. A thermal mass is configured downstream from the fuel reformer and the DPF, but upstream from the LNT. For LNT denitration, the fuel reformer is rapidly heated and then used to catalyze steam reforming. The DPF is also rapidly heat each time the fuel reformer is heated and the LNT denitrated. The system operates to regenerate the DPF each time the LNT is denitrated. Preferably, a second DPF is provided to augment the performance of the first DPF. Preferably, the first DPF is small and of the flow through type whereas the second DPF is much larger and of the wall flow filter type. The second DPF can be used as the thermal mass.

Abstract: An exhaust line fuel injection system and associated methods of operation and control are disclosed. The fuel passes through a regulating valve connected to a pressurized fuel source and an outlet connected to an exhaust system fuel supply line. The exhaust system fuel supply line is connected to a nozzle, which generally comprises a check-valve and is configured to inject the fuel into the exhaust line. Using a pressure measuring device, an indication of the exhaust system fuel supply line pressure is obtained. A controller provides control over the flow regulating valve using feedback from the pressure indication and a predetermined relationship between the flow rate through the nozzle and one of the exhaust system fuel supply line pressure and the pressure drop across the nozzle. The method can be implemented with a single pressure measuring device. The same pressure measurements, especially their frequency spectrum, can be used to detect system faults.

Abstract: Rhodium utilization in LNT/SCR-based exhaust after treatment systems for medium and heavy duty trucks is reduced by operating inline fuel reformers in a certain manner. The fuel processors are operated at steam reforming temperatures to produce a reformate-containing exhaust having a hydrogen to CO ratio of at least about 3:2 or at least about 3% hydrogen, This generally involves operating the fuel reformers at temperatures from about 500 to about 625° C. and with an overall fuel to air ratio from about 1.10 to about 1.40. In this manner, regeneration can be efficiently carried out while limiting the catalyst loading of the fuel processors to no more than about 1.0 grams rhodium per liter maximum displacement of the diesel engine and the catalyst loading of the LNTs to no more than about 0.50 grams rhodium per liter maximum displacement of the diesel engine.

Abstract: A lean NOX trap is a diesel exhaust aftertreatment system is selectively denitrated in a manner that addresses unreliability of NOX sensor data. According to one concept, data from a NOX is ignored or given decreased weight in a period immediately following a denitration. According to another concept, denitration is made contingent on both a first and a second criteria being met. The first criteria relates to the amount of NOX stored in the LNT or remaining NOX storage capacity of the LNT. The second criteria relates to the current performance of the exhaust treatment system, or a portion thereof, as determined from one or more measurements of NOX concentration in the exhaust. This reduces premature denitrations and associated unnecessary fuel expenditures resulting from inaccurate NOX concentration data and transient events.

Abstract: The exhaust from a diesel-fueled internal combustion engine is treated by a lean NOX trap. The maximum temperature used for desulfating the lean NOX trap is kept relatively lower during early life and progressively increased as the trap ages. Designing for adequate late life performance entails excess capacity during early life. The method utilizes the excess capacity available during early life to slow aging of the trap and thereby extend the trap lifetime. The method facilitates meeting durability requirements for diesel-powered vehicles with exhaust aftertreatment.