Abstract: An air handling arrangement in a two-stroke cycle, opposed-piston engine with uniflow scavenging and constructed for heavy-duty operation includes sequentially arranged turbochargers in series with a supercharger. In some aspects, the air handling system is equipped with an EGR channel.

Abstract: An opposed-piston engine includes an electronic sensor located in a charge air channel, at position between an outlet of a charge air cooler and an air intake component that distributes charge air to cylinder intake ports of the engine. The electronic sensor is disposed to measure a rate of mass airflow between the outlet of the charge air cooler and the intake component and generate electronic signals indicative of the rate of mass airflow from the charge air cooler. A control mechanization of the opposed-piston engine is electrically connected to the electronic sensor for controlling air handling devices, fuel provisioning devices, and/or EGR devices in response to the electronic signals.

Abstract: A fuel injector mounting assembly in an opposed-piston engine allows for mounting of a fuel injector in a cylinder block without significantly deforming the wall of the cylinder into which the injector is configured to deliver fuel. The fuel injector mounting assembly includes a clamping arrangement to clamp the fuel injector to the cylinder block, an elongate tubular sleeve that sheathes a nozzle portion of the fuel injector, and a spanner nut attached to the elongate tubular sleeve. Clamping loads applied to retain the fuel injector in the cylinder block are controlled by the spanner nut.

Abstract: A cylinder for opposed-piston engines includes a liner with a bore and longitudinally displaced intake and exhaust ports near respective ends thereof. An intermediate portion of the liner between the exhaust and intake ports contains a combustion chamber formed when the end surfaces of a pair of pistons disposed in opposition in the bore are in close mutual proximity. A compression sleeve encircles and reinforces the intermediate portion of the liner. An annular grid of pegs disposed between the intermediate portion and the compression sleeve supports the compression sleeve against the liner and defines a turbulent liquid flow path extending across the intermediate portion in a direction that parallels the longitudinal axis of the liner.

Abstract: In an opposed-piston engine which includes a catalytic aftertreatment device in its exhaust system an exhaust gas condition indicating a catalyst temperature of the aftertreatment device is monitored. When the catalyst temperature is near or below a light-off temperature, a catalyst light-off procedure is executed to elevate the temperature of the catalyst.

Abstract: A cylinder assembly with a cylinder liner and a sleeve is provided that includes features that reduce coolant flow stagnation. The sleeve encloses a center section of the cylinder liner to form cooling channels that removes excess heat from the combustion area of the cylinder. The cylinder liner includes features for cooling between bridges in the cylinder's exhaust port.

Abstract: An exhaust manifold assembly with a thermal barrier coating for an opposed-piston engine reduces heat rejection to coolant, while increasing exhaust temperatures, fuel efficiency, and quicker exhaust after-treatment light-off. The exhaust manifold assembly can include a coating on the inside surface of the manifold assembly. The coated exhaust manifold assembly can ensure structural robustness of the exhaust manifold assembly over a larger range of operating temperatures.

Abstract: A combination for an opposed-piston engine includes an intake piston and an exhaust piston, each with a top land height. The intake piston top land height is less than the exhaust piston top land height.

Abstract: An air intake system is provided that supplies charge air to multiple cylinders in an in-line configuration in an uniflow-scavenged, two-stroke opposed-piston engine. The engine is configured such that the intake ports of the cylinders are situated in one intake chamber within the engine block. The air intake chamber includes a feature to balance the mass of air that reaches the intake port of each cylinder in the engine.

Abstract: A parent bore cylinder block of an internal combustion, opposed-piston engine includes cooling passages that are formed using a 3-D printed casting core. The casting core can include portions that are ceramic. The parent bore cylinder block can include multiple cylinders, each cylinder with cooling passages and turbulence inducing features in those cooling passages, particularly surrounding the central portions of the cylinders.

Abstract: The air handling system of an opposed-piston engine is equipped with an externally-assisted pumping element such as an electrically-assisted compressor, an electrically-assisted supercharger, or an electrically-assisted turbocharger.

Abstract: In ported engine constructions, cooling of piston crowns and cylinder liners results in reduction or elimination of bore/liner distortions, thus ensuring circularity of the bore/piston interface throughout engine operation. Consequently, the need for heavily-tensioned piston rings is eliminated. Such engine constructions incorporate annular low-tension compression seals on the pistons, which substantially reduce port bridge wear during all phases of engine operation while also limiting blow-by during combustion.

Abstract: Pistons for opposed-piston engines include an interior annular cooling gallery. The gallery is provided with inlet and drain passageways constructed to shield a jet of liquid coolant entering the gallery, thereby reducing interference between the incoming jet and liquid coolant circulating in the gallery.

Abstract: An opposed-piston engine is configured to fit in an engine compartment of a light-duty truck without compromising engine operations or the integrity of the engine compartment. The opposed-piston engine includes an air handling system and can be configured so that a cylinder assembly of the engine is tilted. The tilt of the cylinder assembly can allow for all of the components of the engine's air handling system to be located on one side of the opposed-piston engine. The air handling system of the opposed-piston engine can be configured with a cobra-head shaped intake duct assembly.

Abstract: A main bearing cap construction far a dual-crankshaft, opposed-piston engine has two sets of bolts in a cross-bolted configuration. In a dual-crankshaft opposed-piston engine with at least four main bearings, at least one of the main bearings will have a cap with two sets of bolts in a cross-bolted configuration. In addition to having a cross-bolted configuration, the main bearing cap configuration can have flanges to receive blind bolts and/or additional surface area to interface with the cylinder block.

Abstract: A cylinder liner for an opposed-piston engine, and corresponding methods of extending engine durability and thermal management therewith, has opposite ends and a bore with a longitudinal axis for supporting reciprocating movement of a pair of opposed pistons. An intermediate portion of the liner extends between the opposite ends and includes an annular liner portion within which the pistons reach respective TC locations. A liner ring is seated in a portion of the bore in the annular liner portion, between the TC locations, for scraping carbon from top lands of the pistons and/or increasing the thermal resistance of the annular liner portion.

Abstract: In a supercharged, two-stroke cycle, opposed-piston engine with an EGR loop, exhaust gas recirculated to a charge air channel through which intake air is provided to a supercharger inlet is cleansed of particulate matter by a separator disposed either at a junction where an exhaust channel of the engine is tapped for recirculated exhaust, or, in the EGR loop.

Abstract: A gear train connecting two crankshafts in an opposed-piston engine includes a first crankshaft coupled to first pistons and a second crankshaft coupled to second pistons which are disposed in opposition to the first pistons in cylinders of the engine, a respective crank gear attached to each crankshaft, and an idler gear connecting the crank gears. The gear train comprises a three-gear system that is configured to minimize the side loads on the crankshafts, as well as on an idler gear post.

Abstract: On-board diagnostic monitoring of a two-stroke cycle, opposed-piston engine includes diagnostic monitoring of an air handling system equipped with a supercharger to determine whether the supercharger is functioning properly.

Abstract: A multi-speed drive for a supercharger includes a planetary gear mechanism with a sun gear mechanism, a plurality of planet gears mounted on a planet carrier, and a ring gear, all mounted for rotation on a stationary shaft. A rotary-mechanical drive input is received by either the ring gear or the planetary drive, and a rotary-mechanical drive output is provided by the planetary drive when the ring gear receives the input, or by the ring gear when the planetary drive receives the input. A one-way roller clutch is disposed coaxially with the planetary gear mechanism, between the sun gear mechanism and the stationary shaft. A hydraulically-actuated, clutch assembly mounted coaxially with the planetary gear mechanism on the stationary shaft engages the sun gear and the ring gear to change the gear ratio of the drive.