In particular, an object is to provide a fluid cylinder allowing for accurate stroking while causing rotation with reduced power consumption and a compact configuration. The fluid cylinder of the present invention includes a cylinder body and a shaft member supported within the cylinder body and wherein the shaft member is capable of stroking in an axial direction while rotating by means of a fluid. A rotary driver that rotates the shaft member on the basis of a rotation pressure generated by the fluid and a stroke driver that causes the shaft member to stroke on the basis of a cylinder control pressure generated by the fluid are provided in separate areas within the cylinder body.

The invention relates to a linear drive device having a housing element in which at least one drivable actuating element is arranged, a guide unit which is coupled to the actuation element and moves relative to the housing element between two stroke end positions in linear direction, a stroke limiting device, by means of which a first stroke end position and a second stroke end position of the guide unit are adjustable, wherein the stroke limiting device has a first stop and a first counterstop for setting a limit of the first stroke end position and a second stop and a second counterstop for setting a first limit of the second stroke end position, wherein the stroke limiting device has a third stop which is adapted to set a second limit of the second stroke end position adjusted with the first counterstop.

A levelling system for a vehicle, in particular a rail vehicle, includes at least one levelling cylinder and a levelling piston. The levelling piston is at least partially provided in the levelling cylinder in a movable manner for setting the level of the rail vehicle. Further, the levelling system includes at least one guiding element, which is arranged within the levelling piston and partially protrudes from the levelling piston into at least one recess of the levelling cylinder such that an end stop in a longitudinal direction is provided for the relative movement between the levelling piston and the levelling cylinder.

A hydraulic cylinder is provided with a cylinder tube, a piston unit, and a piston rod. The piston unit has a piston body; packing mounted on the piston body; a holding member mounted on the piston body; and a magnet held by a magnet holding part of the holding member. The magnet holding part has a notch that is open on the outer circumferential surface of the holding member.

A coupling e.g. for an actuator, comprises a housing which is preferably in the form of a ring mounted around the end of the outer rod and which can be mounted to a component e.g. a cowl being deployed. Within the housing of the coupling is provided a ring disk. This is sized and arranged within the housing such that there is some clearance between the ring disk and the housing so as to permit some eccentric movement.

A shaft coupling structure includes a stopper member attached to a piston rod so as to be relatively rotatable and has a plurality of engagement projections and a plurality of slot grooves. The plurality of engagement projections are inserted into the slot grooves, respectively, and include a plurality of inlet grooves and a plurality of inclined engagement grooves extending in a direction inclined from the circumferential direction. The piston rod and a piston member are coupled together through the stopper member so as to be relatively unmovable in the axial direction.

An e.g. fluid powered linear actuator is provided with a helical orientation surface in a fixed angular position relative to a first component; and a follower in a fixed angular position relative to a second component. When the first and second components are moved towards one another as the actuator is retracted, the follower engages and moves along the helical orientation surface to rotate the first and second components to a predetermined relative angular position.

A hydraulic module including a cylinder (2) which accommodates a piston (3) which delimits a chamber (4) which receives the brake fluid. The piston (3) is connected to the electric motor (5) of the module (1) by a recirculating ball screw (6), whose core (61) is fixedly connected to the piston (3) which itself is guided by needles (21) which are parallel to the axis (xx) of the piston (3) and with which notches (351) on the circumference of the piston (3) interact. The piston (3) is a piece, which is formed from a cylindrical body (32) made from anodized aluminum and an outer ring (35) made from steel, which is forcibly mounted on the edge (34) of the piston and is provided with notches (351) with a cross section which corresponds to the effective cross section of the needles (21).

A modular fluid-driven linear actuator comprising an actuator support comprising a first part and a second part configured for relative linear movement, wherein the actuator support is configured to hold a plurality of removable actuator modules in parallel and in respective module-receiving locations defined between the first part and the second part. At least one actuator module is removably installed in the actuator support and held in a respective module-receiving location of the plurality. A first fluid manifold is configured to provide a drive fluid to each actuator module when received in a respective module-receiving location, to act on a piston of the actuator module having a respective piston area to drive the piston in a first direction. A total piston area of the modular actuator is variable by installing and uninstalling actuator modules in the actuator support.

On inner wall surfaces of a head cover and a rod cover of a fluid pressure cylinder, respective pluralities of first and second spigot pins are installed to project out from the inner wall surfaces. The first and second spigot pins are disposed on circumferences of a predetermined diameter that internally contact or inscribe the cylinder tube. Further, when the cylinder tube is assembled with respect to the head cover and the rod cover, by the flange members of the first and second spigot pins inscribing the inner circumferential surface thereof, the cylinder tube is positioned and assembled coaxially with respect to the centers of the head cover and the rod cover.