Abstract:
A cam follower is provided. The cam follower includes a polycrystalline diamond element, including an engagement surface. The engagement surface of the polycrystalline diamond element is positioned on the cam follower for sliding engagement with an opposing engagement surface of a cam. The cam includes at least some of a diamond reactive material.
Abstract:
The valve system for opposed piston engines essentially comprises a single poppet valve opening into the common combustion chamber between the two opposed pistons of each piston and cylinder pair. The engine for which the mechanism is adapted includes a rotating internal cylinder surrounding each piston pair, with a stationary outer cylinder or case surrounding the rotating cylinder. The valve is pivotally attached at one side or end thereof to the edge of the valve port of the rotating cylinder, and is actuated by an arm or arms having guides (rollers, etc.) at the distal end(s) thereof, which are captured in corresponding cam track(s) or channel(s) formed in the fixed outer cylinder or case of the engine. The cam track has a variable radius, with the valve arm(s) and guide(s) alternately lifting and lowering as the guide(s) travel(s) in the variable radius cam track(s), thereby closing and opening the valve.
Abstract:
A reciprocating cylinder seal assembly has an elastomeric seal with a radially inwardly directed oil sealing lip and a radially inwardly directed gas sealing lip, wherein both lips are in elastomeric-to-metal sealing contact with a reciprocating engine liner. The assembly further has a U-shaped seal retainer that is attached to the elastomeric seal, where the U-shaped seal retainer is placed in direct intimate contact with a cylindrical engine housing. The U-shaped seal retainer and a reciprocating engine housing may be separated by and be in contact with a major portion of a J-shaped gas shield with a hook portion that is located between the oil sealing lip and a manifold port, where the hook portion of the J-shaped gas shield has a metal backer ring embedded in it.
Abstract:
A sealing system for sliding sleeves for controlling gas exchange in internal combustion engines. The sealing system is designed such that the pressure on the sealing seat of the sliding sleeve increases when the gas pressure increases, which is similar to that of common valves in internal combustion engines. This is obtained by way of a pressure stage on the inner diameter in the region of the sealing seat of the sliding sleeve. As a result, the maximum outer diameter of the sealing seat does not exceed the inner diameter of the piston running surface of the sliding sleeve, the closing pressure acting upon the sliding sleeve being equal to or greater than the maximum possible opening pressure acting upon the sliding sleeve even when the sealing seat is subjected to a total gas pressure.
Abstract:
The valve system for opposed piston engines essentially comprises a single poppet valve opening into the common combustion chamber between the two opposed pistons of each piston and cylinder pair. The engine for which the mechanism is adapted includes a rotating internal cylinder surrounding each piston pair, with a stationary outer cylinder or case surrounding the rotating cylinder. The valve is pivotally attached at one side or end thereof to the edge of the valve port of the rotating cylinder, and is actuated by an arm or arms having guides (rollers, etc.) at the distal end(s) thereof, which are captured in corresponding cam track(s) or channel(s) formed in the fixed outer cylinder or case of the engine. The cam track has a variable radius, with the valve arm(s) and guide(s) alternately lifting and lowering as the guide(s) travel(s) in the variable radius cam track(s), thereby closing and opening the valve.
Abstract:
A compound engine including a gas turbine unit and a two-stroke uniflow scavenge piston unit having a hollow cylindrical exhaust valve mounted concentrically with an associated piston to form a portion of the combustion chamber within a peripheral wall of the exhaust valve. A double acting exhaust valve actuator is responsive to rotation of the crankshaft and is operatively coupled to the peripheral wall of the hollow cylindrical exhaust valve to produce forces derived directly from rotation of the crankshaft to open and close the exhaust valve. The actuator is a camshaft having two sets of cams which drive a cam follower in response to rotation of the crankshaft.
Abstract:
A wear-resistant copper-based alloy includes: at least one selected from the group made of molybdenum, tungsten, and vanadium and niobium carbide; chromium in an amount of less than 1.0% in terms of wt %; and a matrix and hard particles dispersed in the matrix, in which the hard particles include niobium carbide and at least one selected from the group made of Nb—C—Mo, Nb—C—W, and Nb—C—V around the niobium carbide.
Abstract:
A sleeve valve with a valve body that at least partially encircles at least one piston that moves in a reciprocating manner can, at least partially define with the at least one piston a combustion chamber of an internal combustion engine. A valve actuation mechanism can move the sleeve valve between an open position and a closed position to control flow through a port of the internal combustion engine. The sealing edge of the sleeve valve can be urged against a valve seat by an urging force generated by the valve actuation mechanism when the sleeve valve is moved to the closed position. At least one of the sleeve valve and the valve seat can include a valve assistance feature that assists the valve actuation mechanism in resisting forces generated by the internal combustion engine in opposition to the urging force. Related articles, systems, and methods are described.
Abstract:
A compound engine that includes a gas turbine unit and a piston unit wherein a portion of the cycle air for the piston unit is diverted through cooling passages to provide impingement cooling of several areas of the piston unit including the upper cylinder area, the outer and inner surfaces of the exhaust valve and other selected areas of the cylinder head; and there after, the diverted cycle air is reintroduced into the cycle.
Abstract:
An improved intake and exhaust valve system for internal combustion engines is disclosed. The system includes a primary valve control mechanism for sequentially opening and closing the intake and exhaust valves, and a secondary control system for modifying the operation of the primary mechanism. The primary valve control mechanism includes cylindrical cams for opening and closing the intake and exhaust valves. The secondary control system modifies the operation of the primary valve control system to vary the duration, extent and onset of valve opening and closing. The secondary control system includes a control plate, at least one rocker mechanism mounted to sequentially engage and disengage the control plate, and a driver mounted between the rocker mechanism and at least one of the cylindrical cams of the primary control system so that, when the control plate engages the rocker mechanism, the driver mechanism engages one of the cylindrical cams to modify the operation of the primary control system.