An engine includes a housing and a combustion assembly. The combustion assembly includes an annular bore and a combustion piston assembly disposed within the annular bore. The combustion piston assembly includes a set of pistons, a first sealing ring connected to each piston and a second sealing ring connected to each piston. The second sealing ring is configured to provide selective access between the annular bore and at least one fluid conduit carried by the engine. The engine includes at least one valve configured to move between a first position within the annular bore to allow the combustion piston assembly to travel within the annular bore 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 within the annular bore to define a combustion chamber.

The present invention relates to a tensioning device for a seat belt device, with a gas generator for generating a pressurized gas, a piston that can be driven by the pressurized gas, a tension cable connected to the piston, which tension cable can be connected to a safety belt component that is to be set into a tensioning movement and which tension cable extends through the piston, a guide part arranged on the tension cable, and a tensioning tube for receiving the piston and the guide part, which is characterized in that the guide part is arranged on the side of the piston facing away from the gas generator and is movable relative to the piston.

[Object] To provide a compact, high-output actuator device allowing force control. [Solution] An actuator device 1000 includes an electromagnetic coil member 110 provided over a prescribed width on an outer circumference of a cylinder 100, and a movable element 200 slidable as a piston in the cylinder 100. The movable element 200 has a magnetic member 202, and is moved relatively by excitation of the electromagnetic coil member 110. Fluid is supplied to first and second chambers 106a and 106b such that when the movable element 200 is to be moved relatively, the movable element 200 is driven in the same direction.

An engine includes a housing and a combustion assembly. The combustion assembly includes an annular bore and a combustion piston assembly disposed within the annular bore. The combustion piston assembly includes a set of pistons, a first sealing ring connected to each piston and a second sealing ring connected to each piston. The second sealing ring is configured to provide selective access between the annular bore and at least one fluid conduit carried by the engine. The engine includes at least one valve configured to move between a first position within the annular bore to allow the combustion piston assembly to travel within the annular bore 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 within the annular bore to define a combustion chamber.

The subject matter of this specification can be embodied in, among other things, a fluid actuator including a housing defining a first chamber having a first cavity and a first open end, a first piston assembly including a tubular first piston defining a second chamber having a second cavity and a second open end, disposed in said first housing for reciprocal movement in the first chamber through the first open end, wherein a first seal, the first cavity, and the first piston define a first pressure chamber, and a second piston assembly having an second piston disposed in said first piston assembly for reciprocal movement in the second chamber through the second open end, wherein a second seal, the second cavity, and the second piston define a second pressure chamber, and a first portion of the second piston contacts a first end effector.

Devices and systems for producing rotational actuation are described. Hydraulic and pneumatic actuators can produce and control rotational motion. A rotary joint may be configured to allow parallel coupling of multiple actuators, and thus increase the range of rotation of the actuators when considered collectively. The actuators may include pistons and piston rods having torus shapes. Methods of manufacturing rotary joints are also described.

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.

[Object] To provide a compact, high-output actuator device allowing force control.

[Solution] An actuator device 1000 includes an electromagnetic coil member 110 provided over a prescribed width on an outer circumference of a cylinder 100, and a movable element 200 slidable as a piston in the cylinder 100. The movable element 200 has a magnetic member 202, and is moved relatively by excitation of the electromagnetic coil member 110. Fluid is supplied to first and second chambers 106a and 106b such that when the movable element 200 is to be moved relatively, the movable element 200 is driven in the same direction.

The subject matter of this specification can be embodied in, among other things, a rotary actuator that includes a housing defining an arcuate chamber comprising a cavity, a rotor arm configured for rotary movement, an arcuate-shaped first piston disposed in said housing for reciprocal movement in the arcuate chamber, where a seal, the cavity, and the piston define a pressure chamber that includes part or all of the arcuate chamber, and a portion of the piston contacts the rotor arm, and a rotor assembly rotatably surrounding said housing and having a rotary output tube about the axis, wherein the rotor arm extends radially outward to the rotary output tube and the rotor arm is coupled to the rotary output tube.

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.