A reciprocating cylinder seal assembly (10, 10) has an elastomeric seal, where separate inner (16, 16) and an outer (18, 18) valve seal retainers are located within the reciprocating cylinder seal assembly. The reciprocating cylinder seal assembly (10, 10) better controls radial run out than past seals in reciprocating cylinder engines. Further, the reciprocating cylinder seal assembly may have a scraper (42) that is in contact with the outer valve seal retainer (18).

A reciprocating cylinder seal assembly (10, 10) has an elastomeric seal, where separate inner (16, 16) and an outer (18, 18) valve seal retainers are located within the reciprocating cylinder seal assembly. The reciprocating cylinder seal assembly (10, 10) better controls radial run out than past seals in reciprocating cylinder engines. Further, the reciprocating cylinder seal assembly may have a scraper (42) that is in contact with the outer valve seal retainer (18).

A valve system for internal combustion engines that is controlled by a camshaft is a potential source of engine damage if the timing thereof is disrupted (e.g. when the timing belts rupture). Furthermore, valves in combination with the camshaft and the timing chain contribute to noise and vibrations during operation. The production costs can be high. Thus, the engine is positioned higher and is heavier. Thus, there is proposed a valve mechanism composed of a plurality of gas exchange valves that revolve slowly about the cylinder wall. Each rotary valve is controlled separately and has symmetrical openings. The number of openings in the rotary valve corresponds to the number of working cycles per revolution. Since each rotary valve is driven separately and as a result of the size of the openings in the valve, it is possible to obtain different phase shifts, valve overlaps and opening times.

A multicylinder internal combustion free-piston engine (FPE) with synchronized reciprocating plungers. The invention provides a solution for the problem of the slow engine speed typical of FPE's with heavy plunger mass. Bounce chambers fitted with sleeve valves control the engine's speed and stroke length. The invention's configuration prevents piston head-strikes and operates at standard compression ratios. Piston pop-top intake valves allow uniflow scavenging and connecting rod oil channels provide lubrication with no combustion chamber contamination. Poppet combustion head valves are operated by linear cams attached to the plungers. Hydraulic valve actuators implement variable valve timing under computer control.

A multicylinder internal combustion free-piston engine (FPE) with synchronized reciprocating plungers. The invention provides a solution for the problem of the slow engine speed typical of FPE's with heavy plunger mass. Bounce chambers fitted with sleeve valves control the engine's speed and stroke length. The invention's configuration prevents piston head-strikes and operates at standard compression ratios. Piston pop-top intake valves allow uniflow scavenging and connecting rod oil channels provide lubrication with no combustion chamber contamination. Poppet combustion head valves are operated by linear cams attached to the plungers. Hydraulic valve actuators implement variable valve timing under computer control.

A valve system for internal combustion engines that is controlled by a camshaft is a potential source of engine damage if the timing thereof is disrupted (e.g. when the timing belts rupture). Furthermore, valves in combination with the camshaft and the timing chain contribute to noise and vibrations during operation. The production costs can be high. Thus, the engine is positioned higher and is heavier. Thus, there is proposed a valve mechanism composed of a plurality of gas exchange valves that revolve slowly about the cylinder wall. Each rotary valve is controlled separately and has symmetrical openings. The number of openings in the rotary valve corresponds to the number of working cycles per revolution. Since each rotary valve is driven separately and as a result of the size of the openings in the valve, it is possible to obtain different phase shifts, valve overlaps and opening times.