An actuator includes a body and at least a first offset connection port that is connected to the body by a first duct projecting from the body. The first connection port is mechanically connected to the body at least by first and second struts. The first strut and the second strut extend from the first connection port, respectively, to a first segment of the body and to a second segment of the body that is axially spaced apart from the first segment.

An undercarriage includes such an actuator as its locking or unlocking actuator.

The invention relates to a hydraulic cylinder, for example for use with a hydraulic tool, which hydraulic tool is provided with a frame and an element which is movable with respect to the frame by means of the hydraulic cylinder. A hydraulic tool which is operated by means of a hydraulic cylinder as described above is known from, for example, European patent no. 0641618. This patent discloses a frame which is coupleable to a jib of an excavator or the like and to which an assembly of two jaws can be coupled. One of the jaws is pivotable with respect to the other jaw by means of a hydraulic adjusting cylinder (a double-acting piston/cylinder combination).

Methods and systems relating to improvements in reliability of fluid power actuators are disclosed. An exemplary fluid power actuator (300) comprises, an actuator body (305) having a cylindrical cavity (310), fitted with a first end cap (315) and a second end cap (320) at longitudinal ends, a piston (325) with a piston rod (330) disposed inside the cylindrical cavity (310), wherein the actuator (300) is characterised by, a hollow tie rod (335) in the cylindrical cavity (310), wherein the hollow tie rod (335) is for conveying a pressurised fluid into a volume (A) in the cylindrical cavity (310) between the second end cap (320) and the piston (325) for exerting a force on the piston (325) for a stroke or stroke reversal. The hollow tie rod 335 serves dual purpose of holding the pressure retaining components together, providing a flow path for the fluid enabling actuator stroking and stroke reversal.

An output member (7) is inserted in a housing (5) so as to be movable in a left-right direction. A lock chamber (20) is provided to the right of the output member (7), as a first actuation chamber. Compressed air is supplied to and discharged from the lock chamber (20) through a first supply and discharge passage (24) provided in the housing (5). A first holding valve (30) provided to an intermediate portion of the first supply and discharge passage (24) is configured to close and open the first supply and discharge passage (24).

A single-use pressure-controlled actuator for downhole well tools or mechanisms is provided. The actuator is configured for control of activation/deactivation by agency of wellbore fluid pressure (e.g., pressure levels of drilling fluid or drilling mud in the wellbore). The actuator is further configured for hydraulic actuation by agency of the wellbore fluid. The actuator comprises a plunger displaceably mounted on a sealed cylinder body, with a non-reclosable frangible device closing off wellbore fluid access to an interior of the cylinder body. The frangible device is configured for automatic in response to exposure of wellbore fluid pressures exceeding a predetermined activation threshold. Failure of the frangible device causes exposure of the plunger to the wellbore fluid, resulting in actuated movement of the plunger by hydraulic action of the wellbore fluid.

A hydraulic device having: a plurality of main piston-cylinder arrangements, each of the respective pistons having a fixed stroke length and configured for axial reciprocation within their respective cylinder; a plurality of flow control valves for switching between a lockdown state and an unlocked state of one or more of the plurality of main piston cylinder arrangements during operation of the hydraulic device; and one or more control valves for directing the plurality of flow control valves between their respective unlock and lock positions.

An actuation device for a human-powered vehicle comprises a base member, a movable member, and an actuator. The movable member is movably provided on the base member. The actuator is configured to be actuated by stimulation including at least one of electric stimulation and heat stimulation so as to move the movable member relative to the base member in a first direction by pulling the movable member.

A hydraulic actuator is disclosed that comprises a first, fixed portion and a second portion movable relative to the first portion. The second portion comprises a hydraulic actuating device for actuating a component, and the actuator further comprises an intermediate member configured to interconnect the first portion with the second portion and permit movement of the second portion relative to the first portion. The intermediate member is configured to convey hydraulic fluid to the hydraulic actuating device of the second portion through a body of the intermediate member.

A hydraulic power generating system includes a hydraulic motor, a bidirectional generator connected to the hydraulic motor, a hydraulic cylinder, first and second tubes, a piston structure having a piston and first and second links, and a power driving device connected to the first link. The piston divides the hydraulic cylinder into first and second chambers. The first and second links are connected to the piston and disposed through the first and second chambers, respectively. The first tube is communicated with the first chamber and the hydraulic motor. The second tube is communicated with the second chamber and the hydraulic motor. When the power driving device drives the piston toward the first chamber, hydraulic oil is pumped to the hydraulic motor for rotating the bidirectional generator. When the power driving device drives the piston toward the second chamber, the hydraulic oil is pumped to rotate the bidirectional generator reversely.

A pneumatic actuator and control valve assembly has a housing with a control cavity for a control valve and an actuator cavity for an actuator piston and rod assembly. The control cavity and actuator cavity both have an elongated shape and are substantially parallel to each other. The control cavity has a supply port and first and second control valve outlet ports and at least one vent port with the control valve being movable through the control cavity for controlling communication between the supply port and the first and second outlet ports. The actuator cavity has first and second ports at the retracted and extended ends for shuttling the piston and within the actuator cavity between a retracted and extended end position. The housing has a first inlet and second inlet for passage of pressurized fluid to and from the housing,