An engine includes a housing defining an annular bore and a piston assembly disposed within the annular bore. The engine includes at least one valve configured to oscillate between a first position within the annular bore to allow the piston assembly to travel from a first location proximate to the at least one valve to a second location distal to the at least one valve and a second position to define a combustion chamber relative to the piston assembly at the second location. The engine includes an exhaust gas port disposed in fluid communication with the combustion chamber and a fuel distribution assembly configured to mix fuel from a fuel source and air from an air source into a fuel and air mixture at a location external to the combustion chamber and to deliver the fuel and air mixture to the combustion chamber.

An engine includes a housing defining an annular bore and a piston assembly disposed within the annular bore. The engine includes at least one valve configured to oscillate between a first position within the annular bore to allow the piston assembly to travel from a first location proximate to the at least one valve to a second location distal to the at least one valve and a second position to define a combustion chamber relative to the piston assembly at the second location. The engine includes an exhaust gas port disposed in fluid communication with the combustion chamber and a fuel distribution assembly configured to mix fuel from a fuel source and air from an air source into a fuel and air mixture at a location external to the combustion chamber and to deliver the fuel and air mixture to the combustion chamber.

An apparatus including a first piston member rotatable about a first rotational axis and a rotor with a first chamber and pivotable about a second rotational axis. The first piston member extends across the first chamber. The rotor and first piston member are rotatable around the first rotational axis, and the rotor is pivotable about the second rotational axis to permit a relative pivoting motion between the rotor and the first piston member linked to the rotor rotating about the first rotational axis.

A rotary actuator, including a manifold block and a rotor assembly that includes a rotor shaft and a plurality of arcuate pistons attached to the rotor shaft, each arcuate piston curving at a set radial distance from the rotor shaft, and each piston attached to the rotor shaft via a crank arm. A pressure chamber assembly coupled to the manifold block defines a plurality of piston pressure chambers that receive and at least partially enclose each arcuate piston, including a plurality of gland seals disposed adjacent the entrance of each piston pressure chamber to create a seal between the inner surface of the pressure chamber and the outer surface of the arcuate piston. Each gland seal includes an inner seal that engages the piston surface of the arcuate piston, and plural outer seals that engage the inner surface of the piston pressure chamber, forming a hydraulic seal.

A shaft extending along a longitudinal axis has fluid channels that increase and decrease pressure in chambers formed between the interior ends of curved pistons and adjacent closed ends of curved chambers within which the pistons reciprocate as the chamber pressure increases and decreases. The chambers and pistons are in separate cylinder block segments extending outward from opposing sides of the shaft. Each segment may have two sides extending along radial planes and joined by a curved outer surface. Pistons may be provided in pairs and have an interior piston end of each piston in a different cavity in different segments. Exterior ends of each piston in a pair of pistons are connected to a piston connector that extends inwardly from a housing so the housing rotates with the pistons.

The subject matter of this specification can be embodied in, among other things, a rotary actuator that includes a first rotary actuator assembly having a first housing, a first mounting assembly radially projecting from a first longitudinal end of the first housing and defining a first axial aperture, and a first output shaft extending into the first axial aperture, a second rotary actuator assembly having a second housing, a second mounting assembly radially projecting from a second longitudinal end of the second housing and defining a second axial aperture, and a second output shaft extending into the second axial aperture, and a bearing assembly having an outer surface in contact with at least one of the first mounting assembly and the second mounting assembly, and an inner surface in contact with at least one of the first rotor assembly and the second rotor assembly.

A roticulating thermodynamic apparatus (100) having a first fluid flow section (111) and a second fluid flow section (115). The first fluid flow section (111) is configured for the passage of fluid between a first port (114a) and second port (114b) via a first chamber (134a). The second fluid flow section (115) is configured for the passage of fluid between a third port (116a) and a fourth port (116b) via a second chamber (134, 234b). The second port (114b) is in fluid communication with the third port (116a) via a first heat exchanger (302a).

A roticulating thermodynamic apparatus (100) having a first fluid flow section (111) and a second fluid flow section (115). The first fluid flow section (111) is configured for the passage of fluid between a first port (114a) and second port (114b) via a first chamber (134a). The second fluid flow section (115) is configured for the passage of fluid between a third port (116a) and a fourth port (116b) via a second chamber (134, 234b). The second port (114b) is in fluid communication with the third port (116a) via a first heat exchanger (302a).

The subject matter of this specification can be embodied in, among other things, a rotary actuator that includes a housing defining a first arcuate chamber portion and comprising a first cavity, a first open end, a first seal carrier assembly defining a second arcuate chamber portion and comprising a second cavity in fluid communication with the first cavity, a first piston seal, a second open end, and a third open end opposite the second open end, a first face seal in sealing contact with the housing proximal to the first open end and the second open end, a rotary output assembly, and an arcuate-shaped first piston disposed in said housing for reciprocal movement in the first arcuate chamber portion and in the second arcuate chamber portion.

A rotary actuator, including a manifold block and a rotor assembly that includes a rotor shaft and a plurality of arcuate pistons attached to the rotor shaft, each arcuate piston curving at a set radial distance from the rotor shaft, and each piston attached to the rotor shaft via a crank arm. A pressure chamber assembly coupled to the manifold block defines a plurality of piston pressure chambers that receive and at least partially enclose each arcuate piston, including a plurality of gland seals disposed adjacent the entrance of each piston pressure chamber to create a seal between the inner surface of the pressure chamber and the outer surface of the arcuate piston. Each gland seal includes an inner seal that engages the piston surface of the arcuate piston, and plural outer seals that engage the inner surface of the piston pressure chamber, forming a hydraulic seal.