Abstract: In a two-cycle, opposed-piston internal combustion engine, opposed pistons disposed in a cylinder are coupled to a pair of side-mounted crankshafts by connecting rods that are subject to substantially tensile forces acting between the pistons and the crankshafts. This geometry reduces or eliminates side forces between the pistons and the bore of the cylinder. The cylinder and the pistons are independently cooled to reduce cylindrical deformation caused by thermal expansion during engine operation.

Abstract: In a two-stroke, opposed-piston internal combustion engine with optimized cooling and no engine block, the opposed pistons are coupled to a pair of crankshafts by connecting rods that are subject to substantially tensile forces acting between the pistons and the crankshafts.

Abstract: An engine of the opposed piston, two-stroke, compression ignition type includes provision for injection of a main charge of liquid fuel into the bore of a cylinder between opposed pistons early in a compression stroke to permit the fuel to evaporate and mix with air during the remainder of the compression stroke to the point where the stoichiometric components of the mixture are insufficient for autoignition. Further provision is made for injection of a pilot charge of liquid fuel into the compressed air/fuel mixture later in the compression stroke. The pilot charge provides a stoichiometric component which autoignites, thereby activating ignition of the compressed air/fuel mixture.

Abstract: A two-cycle, opposed piston engine with side-mounted crankshafts and cylinders isolated from mechanical stresses of the engine includes tailored cooling of cylinders and symmetrical cooling of the interior surfaces of piston crowns. Each opposed piston includes a compliant member that permits movement of an axially-centered rod mounted in the piston in order to maintain axial alignment with the bore of a cylinder in which the piston is disposed during engine operation. A single wristpin is disposed externally of the piston to connect the piston with connecting rods that run between the piston and the crankshafts.

Abstract: In a two-cycle, opposed-piston internal combustion engine with optimized cooling and no engine block, the opposed pistons are coupled to a pair of crankshafts by connecting rods that are subject to substantially tensile forces acting between the pistons and the crankshafts.