Abstract: A combustion chamber for an opposed-piston engine has a rotationally skewed shape in a longitudinal section that is orthogonal to a chamber centerline, between diametrically-opposed openings of the combustion chamber through which fuel is injected. The rotationally skewed shape interacts with swirl to generate a tumble bulk charge air motion structure that increases turbulence.

Abstract: In an air handling system of a uniflow-scavenged, two-stroke cycle opposed-piston engine, repeatable trapped mass and composition are achieved by determining provision of air handling setpoints that control operation of the engine's air handling system components. In some aspects, these setpoints govern operations of the air handling system by actively controlling the intake manifold pressure (IMP), EGR flow, and exhaust channel backpressure.

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: An opposed-piston engine includes an inline cylinder block with an open exhaust chamber that contains all of the engine's exhaust ports. Exhaust outlets open from the exhaust chamber through opposing sides of the cylinder block. A turbocharger is positioned on each side of the cylinder block and has an inlet closely coupled with a respective exhaust outlet. The exhaust chamber is divided into separate collector sections, each collector section containing the exhaust ports of one or more cylinders, and each turbocharger has a first inlet closely coupled with a first collector section and a second inlet closely coupled with a second collector section. The engine has a cylinder firing sequence which alternates between the cylinders in the first and second collector sections.

Abstract: Backlash is controlled in an opposed-piston engine that includes two crankshafts disposed in a parallel, spaced-apart relationship and a gear train coupling the first and second crankshafts, the gear train including a driving gear coupled to the first crankshaft and a split gear assembly engaged with the driving gear to transfer rotation from the driving gear to the split gear assembly. The split gear assembly includes first and second gears, a spring mechanism that acts to angularly offset the first gear relative to the second gear in a first direction, and a one-way clutch mechanism that prevents relative angular movement of the first gear relative to the second gear in a second direction opposite the first direction.

Abstract: An engine structure for a multi-cylinder, opposed-piston engine includes a cylinder block with a plurality of inline cylinders. Each cylinder has ends with an outside diameter and an intermediate portion between the ends of a relatively larger outside diameter than the ends. The cylinder block includes a bearing web structure that positions bearing web elements outside of a plane that longitudinally bisects all of the cylinders. The cylinder block is split into two sections so as to permit cylinder liners to be inserted into and removed from cylinder tunnels in the cylinder block.

Abstract: An opposed-piston engine has a cylinder block with a plurality of cylinders arranged inline, with each cylinder including an intake port longitudinally separated from an exhaust port. The engine's air handling system includes open intake and exhaust chambers in the cylinder block. The open chamber constructions eliminate the need for multi-pipe manifolds and smooth the flow of charge air.

Abstract: An opposed-piston engine has a cylinder block with a plurality of cylinders arranged inline, with each cylinder including an intake port longitudinally separated from an exhaust port. The engine is equipped with an air handling system that includes intake and exhaust chambers inside the cylinder block. All of the cylinder intake ports are contained in the intake chamber to receive charge air therein. The intake chamber includes elongated air inlets opening through opposing sides of the cylinder block. The exhaust chamber includes at least one exhaust outlet opening through a side of the cylinder block; all of the cylinder exhaust ports are contained in the exhaust chamber to discharge exhaust thereinto.

Abstract: Pressurized lubricating oil is accumulated in the bearings of opposed pistons and accumulated oil is dispensed therefrom for bearing lubrication and also for cooling the undercrowns of the pistons by jets of oil emitted from the bearings.

Abstract: The structure of a cylinder with longitudinally-separated exhaust and intake ports includes a powdered metal (PM) ring sintered over grooves and/or slots in the exhaust port bridges and/or the top center (TC) portion of a cylinder liner.

Abstract: The air handling system of a turbocharged opposed-piston engine with uniflow scavenging includes an a supercharger operable to provide boost during startup and to drive EGR during normal engine operation.

Abstract: A lubricating configuration in a two-stroke cycle, opposed-piston engine for a piston wristpin minimizes losses in oil pressure at the wristpin as the piston approaches bottom center and reduces the required oil supply pressure to the engine. The wristpin is constructed to absorb and store oil pressure energy when oil pressure at the wristpin is high, and to release that stored energy to pressurize the oil at the wristpin when connecting rod oil pressure is low.

Abstract: A lubricating configuration in a two-stroke cycle, opposed-piston engine for a piston wristpin minimizes losses in oil pressure at the wristpin as the piston approaches bottom center and reduces the required oil supply pressure to the engine. The wristpin is constructed to absorb and store oil pressure energy when oil pressure at the wristpin is high, and to release that stored energy to pressurize the oil at the wristpin when connecting rod oil pressure is low.

Abstract: A strategy to cold-start an opposed-piston engine includes, before injecting fuel, preventing air flow through the engine while cranking the engine to heat air retained in the engine, followed by controlling mass air flow through and fuel injection into a cylinder of the engine according to cold-start schedules so as to create and preserve heat for stable engine firing and transition to an idling state of operation.

Abstract: A combustion chamber construction for opposed-piston engines in which fuel is injected from two opposed injectors includes a dual mixing region construction with a respective mixing region for each injector and a coupling region between the two mixing regions through which the mixing regions communicate. In some aspects, the mixing regions are bulbous and are connected by a waist, or tunnel, region that is relatively narrower than the bulbous mixing chambers.

Abstract: An opposed-piston internal combustion engine with one or more ported cylinders and uniflow scavenging includes fuel injectors supported at compound angles with respect to the cylinders in order to directly inject spray patterns of fuel in opposing directions through the side walls of the cylinders.

Abstract: In a two-stroke opposed-piston engine, a ported cylinder with a pair of opposed pistons is equipped with an engine brake including an engine braking valve that can be opened to release air from the cylinder as the pistons cycle between BDC and TDC positions.

Abstract: In a two-stroke opposed-piston engine, a ported cylinder with a pair of opposed pistons is equipped with an engine brake including an engine braking valve that can be opened to release air from the cylinder as the pistons cycle between BDC and TDC positions.

Abstract: A quiet-running, multi-layer gear assembly includes a stiff center member sandwiched between a pair of outer members. At least one of the outer members is compliant; preferably, both are. The stiff center member has an outer peripheral surface with gear teeth. Each of the outer members has an outer peripheral surface with gear teeth disposed in a respective directed axial thrust pattern. The center and outer members are joined on a central hub with their outer peripheral surfaces aligned so as to form a gear assembly.

Abstract: A ported cylinder for an opposed-piston engine has a bore to support movements of a pair of opposed pistons and longitudinally-spaced intake and exhaust ports that are controlled by movements of oppositely-disposed pistons in the bore. The bore includes a central portion where combustion occurs and respective end portions. Each end portion extends from an inner edge of a port to the nearest open end of the cylinder. In the central portion the bore has a standard diameter throughout. The bore has a second, larger diameter in each end portion. When the cylinder liner is cold, the bore diameter transitions continuously in size, from the standard diameter to the larger diameter, in an area running from the central portion to an inner edge of a port. From the inner edge, the bore is of the larger diameter throughout the end portion.