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: 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: A dual-crankshaft, opposed-piston, internal combustion engine includes one or more ported cylinders. Each cylinder has exhaust and intake ports, and the cylinders are juxtaposed and oriented with exhaust and intake ports mutually aligned. The crankshafts are rotatably mounted at respective exhaust and intake ends of the cylinders and are coupled by a multi-gear train. A pair of pistons is disposed for opposed sliding movement in the bore of each cylinder. All of the pistons controlling the exhaust ports are coupled by connecting rods to the crankshaft mounted near at the exhaust ends of the cylinders, and all of the pistons controlling the intake ports are coupled by connecting rods to the crankshaft mounted near at the intake ends of the cylinders. The crankshafts are connected by a timing belt operative to change the rotational timing between the crankshafts. The gear train support structure is stiffened to suppress gear train vibration.

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: A piston construction with an end surface is equipped with a pattern of insulating cavities embedded in an upper end of the piston, between the end surface and interior portions of the piston that are cooled by circulating liquid coolant.

Abstract: A passive, noninvasive tomography apparatus and method is disclosed for in-depth tissue imaging and lesion detection. In one particular approach, the disclosed apparatus and method is adapted for use in breast imaging.

Abstract: A piston rolling thrust bearing construction is constituted of a pair of bearing plates with opposing faces disposed in a spaced alignment with a rolling ball assembly positioned between the opposing faces to support relative movement between the bearing plates. The piston rolling thrust bearing is mounted to the open end of the skirt of a piston disposed in a cylinder to compensate for non-axial motion relative to the cylinder axis due to the articulating motions of connecting elements or any structural misalignments within an engine drive train assembly.

Abstract: In a two-stroke opposed-piston engine, a ported cylinder with a pair of opposed pistons is equipped with a decompression port including a valve and a passage with an opening through the cylinder wall that is located between the cylinder's intake and exhaust ports. The decompression port enables release of compressed air from the cylinder after the intake and exhaust ports are closed. The valve is opened to permit compressed air to be released from the cylinder through the passage, and closed to retain compressed air in the cylinder. Engine braking is supported by release of compressed air through the decompression port into an exhaust channel when the pistons are at or near top dead center positions as the cycle transitions from the intake/compression stroke to the power/exhaust stroke. Compression release from the cylinder after intake and exhaust port closure can also support other engine operations.

Abstract: Integrated, multi-cylinder opposed engine constructions include a unitary support structure to which cylinder liners are removeably mounted and sealed and on which crankshafts are rotatably supported. The engine constructions include a cooled piston with a resiliently deformable joint connecting crown and skirt and a cooled cylinder liner with wipers to manage lubricant in the cylindrical interstice between the cylinder bore and the piston skirts.

Abstract: Integrated, multi-cylinder opposed engine constructions include a unitary support structure to which cylinder liners are removeably mounted and sealed and on which crankshafts are rotatably supported. The engine constructions include a cooled piston with a resiliently deformable joint connecting crown and skirt and a cooled cylinder liner with wipers to manage lubricant in the cylindrical interstice between the cylinder bore and the piston skirts.

Abstract: Integrated, multi-cylinder opposed engine constructions include a unitary support structure to which cylinder liners are removeably mounted and sealed and on which crankshafts are rotatably supported. The unitary support structure includes cooling manifolds that provide liquid coolant to the cylinder liners. Exhaust and intake manifolds attached to the support structure to serve respective ports in the cylinder liner. The engine constructions may also include certain improvements in the construction of cooled pistons with flexible skirts, and in the construction of cylinders with sealing structures mounted outside of exhaust and inlet ports to control lubricant in the cylindrical interstice between the through bore and the pistons.

Abstract: In an opposed piston, compression ignition engine two crankshafts are single-side mounted with respect to a row of cylinders, which is to say that the crankshafts are mounted so that their axes of rotation lie in a plane that is spaced apart from and parallel to a plane in which the axes of the cylinders lie. Each piston of the engine is coupled to one of the crankshafts by a single linkage guided by a crosshead. The piston has a piston rod affixed at one end to the piston. The other end of the piston rod is affixed to the crosshead pin. One end of a connecting rod swings on the pin and the other end is coupled to a throw on a crankshaft. Each crosshead is constrained to reciprocate between fixed guides, in alignment with the piston rod to which it is coupled.

Abstract: In an opposed piston, compression ignition engine two crankshafts are single-side mounted with respect to a row of cylinders, which is to say that the crankshafts are mounted so that their axes of rotation lie in a plane that is spaced apart from and parallel to a plane in which the axes of the cylinders lie. Each piston of the engine is coupled to one of the crankshafts by a single linkage guided by a crosshead. The piston has a piston rod affixed at one end to the piston. The other end of the piston rod is affixed to the crosshead pin. One end of a connecting rod swings on the pin and the other end is coupled to a throw on a crankshaft. Each crosshead is constrained to reciprocate between fixed guides, in alignment with the piston rod to which it is coupled.

Abstract: A passive, noninvasive tomography apparatus and method is disclosed for in-depth tissue imaging and lesion detection. In one particular approach, the disclosed apparatus and method is adapted for use in breast imaging.

Abstract: A dual-crankshaft, opposed-piston, internal combustion engine includes one or more ported cylinders. Each cylinder has exhaust and intake ports, and the cylinders are juxtaposed and oriented with exhaust and intake ports mutually aligned. The crankshafts are rotatably mounted at respective exhaust and intake ends of the cylinders and are coupled by a multi-gear train. A pair of pistons is disposed for opposed sliding movement in the bore of each cylinder. All of the pistons controlling the exhaust ports are coupled by connecting rods to the crankshaft mounted near at the exhaust ends of the cylinders, and all of the pistons controlling the intake ports are coupled by connecting rods to the crankshaft mounted near at the intake ends of the cylinders. The crankshafts are connected by a timing belt operative to change the rotational timing between the crankshafts. The gear train support structure is stiffened to suppress gear train vibration.

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: An internal combustion engine including a cylinder with bore and a piston disposed to reciprocate in the bore is operated by moving the piston in the bore between top and bottom dead center positions and applying lubricant to a portion of the piston that protrudes from the bore. Lubricant is wiped from the piston as the piston travels into the bore toward its top dead center position.

Abstract: An opposed piston engine includes at least one cylinder with inlet and exhaust ports and opposed pistons disposed in the cylinder for reciprocating opposed motion toward and away from each other. An auxiliary system pumps liquid coolant separately to the cylinder and pistons. Another auxiliary system controls the flow of intake and exhaust gas in the engine.

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 engine, a ported cylinder with a pair of opposed pistons is equipped with a decompression port including a valve and a passage with an opening through the cylinder wall that is located between the cylinder's intake and exhaust ports. The decompression port enables release of compressed air from the cylinder after the intake and exhaust ports are closed. The valve is opened to permit compressed air to be released from the cylinder through the passage, and closed to retain compressed air in the cylinder. Engine braking is supported by release of compressed air through the decompression port into an exhaust channel when the pistons are at or near top dead center positions as the cycle transitions from the intake/compression stroke to the power/exhaust stroke. Compression release from the cylinder after intake and exhaust port closure can also support other engine operations.