In an internal combustion engine, first and second rotating members, one for the intake valve and one for the exhaust valve rotate next to the outside of an engine cylinder on opposite sides thereof when driven by a drive gear attached to the end of the engine's crankshaft. Each rotating member may include a ring gear having a valve port or aperture near its perimeter that cyclically aligns with a corresponding valve port formed through the cylinder wall near the top of the cylinder. A method of controlling valve timing comprises the steps of causing the rotating member containing the second valve port to periodically align in synchronism with the first port to control the passage of an air/fuel mixture and exhaust gases through the combustion cycles of the engine.

An internal combustion engine is provided. Facing pistons eliminate a cylinder head, thereby reducing heat losses through a cylinder head. Facing pistons also halve the stroke that would be required for one piston to provide the same compression ratio, and the engine can thus be run at higher revolutions per minute and produce more power. An internal sleeve valve is provided for space and other considerations. A combustion chamber size-varying mechanism allows for adjustment of the minimum size of an internal volume to increase efficiency at partial-power operation. Variable intake valve operation is used to control engine power.

An internal combustion engine is provided. Facing pistons eliminate a cylinder head, thereby reducing heat losses through a cylinder head. Facing pistons also halve the stroke that would be required for one piston to provide the same compression ratio, and the engine can thus be run at higher revolutions per minute and produce more power. An internal sleeve valve is provided for space and other considerations. A combustion chamber size-varying mechanism allows for adjustment of the minimum size of an internal volume to increase efficiency at partial-power operation. Variable intake valve operation is used to control engine power.

An opposed piston engine is provided. The engine includes a mechanism enabling adjustment of a compression ratio of the engine.

An inventive opposed piston engine is provided. The inventive engine includes an inventive mechanism that enables adjustment of a compression ratio of the engine.

An inventive opposed piston engine is provided. The inventive engine includes an inventive mechanism that enables adjustment of a compression ratio of the engine.

In an internal combustion engine, first and second rotating members, one for the intake valve and one for the exhaust valve rotate next to the outside of an engine cylinder on opposite sides thereof when driven by a drive gear attached to the end of the engine's crankshaft. Each rotating member may include a ring gear having a valve port or aperture near its perimeter that cyclically aligns with a corresponding valve port formed through the cylinder wall near the top of the cylinder. A method of controlling valve timing comprises the steps of causing the rotating member containing the second valve port to periodically align in synchronism with the first port to control the passage of an air/fuel mixture and exhaust gases through the combustion cycles of the engine.

In an internal combustion engine, first and second rotating members, one for the intake valve and one for the exhaust valve rotate next to the outside of an engine cylinder on opposite sides thereof when driven by a drive gear attached to the end of the engine's crankshaft. Each rotating member may include a ring gear having a valve port or aperture near its perimeter that cyclically aligns with a corresponding valve port formed through the cylinder wall near the top of the cylinder. A method of controlling valve timing comprises the steps of causing the rotating member containing the second valve port to periodically align in synchronism with the first port to control the passage of an air/fuel mixture and exhaust gases through the combustion cycles of the engine.

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).