Manual hydraulic override pumps for use with actuators are described herein. An example apparatus includes a manifold including a reservoir port to be fluidly coupled to a reservoir of fluid, a pump port to be fluidly coupled to a pump, a first actuator port to be fluidly coupled to a first chamber of an actuator, and a second actuator port to be fluidly coupled to a second chamber of the actuator. The example apparatus also includes a rotor disposed in a cavity formed in the manifold. The rotor is rotatable between a first actuating position in which the rotor fluidly couples the first actuator port and the pump port, and a second actuating position in which the rotor fluidly couples the second actuator port and the pump port.

A variable flow hydraulic device having a plurality of cylinders for varying a flow of hydraulic fluid between a reservoir and a load, the device comprising: a housing having the plurality of cylinders with a plurality of corresponding pistons; an input port of the housing fluidly connected to each cylinder of the plurality of cylinders, the input port facilitating introduction of the hydraulic fluid to said each cylinder; a first output port of the housing connected to said each cylinder, the first output port facilitating the ejection of the hydraulic fluid from said each cylinder, the first output port configured for fluidly coupling said each cylinder to the load; a respective flow control valve for said each cylinder, and a fluid pressure sensing device coupled between downstream of the first output port and said respective flow control valve.

A lifting apparatus for lifting drill string components from a wellbore, the lifting apparatus comprising: upper and lower support elements, each of the support elements having a central aperture passing therethrough; a lifting arrangement which is operable to vary the distance between the upper and lower support elements between a first, relatively short distance and a second, relatively long distance; and selective gripping arrangements held or supported by the upper and lower support elements, respectively, each selective gripping arrangement being operable to apply a gripping force to the exterior of a substantially tubular element passing through the central apertures of the upper and lower support elements, wherein the selective gripping arrangements may be activated or deactivated independently of one another.

A fluidic logic and actuator system for outputting a displacement having a fluidic logic circuitry layer including a fluidic control input and a plurality of fluidic latching memory units. At least some of the plurality of fluidic latching memory units are configured to perform combinatorial and sequential logic functions and output a fluid response. A fluid actuator layer is provided having a plurality of fluid actuators, wherein each of the plurality of fluid actuators being movable in response to the fluid response of a corresponding one of the plurality of fluidic latching memory units.

Provided are embodiments of a pressure-compensated load transfer device that includes a plate having a first shaft vertically installed on one side and a second shaft vertically installed on the other side to be coaxial with the first shaft. Also included is a first bellows having an opening in one side to surround the first shaft, with the other side thereof being fixed to the one side of the plate. Further included is a plurality of second bellows each having an opening in one end, with the other end thereof being attached to the other side of the plate. A housing is also included, and the housing includes a high-pressure working hole communicating with the opening of the first bellows and a high-pressure channel coplanar with the high-pressure working hole and communicating with the openings of the second bellows. The plate is back-and-forth movably received in the housing.

A hydraulic operating device for a fluid of a cycle or of a motorcycle hydraulic system including a body, a first chamber carved in the body adapted to house an actuating piston, a second tank-chamber carved in the body and in fluid communication with said first chamber, a floating plug, a sphere, an elastic element, a rear sealing element and a rear plug.

An air cylinder includes a cylinder, a piston rod, a piston, and a controller. The piston rod has one end disposed in the cylinder and the other end protruding from the cylinder. The piston is provided at the one end of the piston rod and moves the piston rod by moving in the cylinder. The controller supplies gas into one of a space, which is a space in the cylinder directed on the piston rod side with respect to the piston, and a space, which is a space in the cylinder opposite to the space with respect to the piston, and sucks gas from an interior of the other of the spaces.

A variable flow hydraulic device having a plurality of cylinders for varying a flow of hydraulic fluid between a reservoir and a load, the device comprising: a housing having the plurality of cylinders with a plurality of corresponding pistons; an input port of the housing fluidly connected to each cylinder of the plurality of cylinders, the input port facilitating introduction of the hydraulic fluid to said each cylinder; a first output port of the housing connected to said each cylinder, the first output port facilitating the ejection of the hydraulic fluid from said each cylinder, the first output port configured for fluidly coupling said each cylinder to the load; a respective flow control valve for said each cylinder, and a fluid pressure sensing device coupled between downstream of the first output port and said respective flow control valve.

A hydraulic actuator has a lower cylinder comprising a lower cylinder extension area and a lower cylinder retraction area, an upper cylinder comprising an upper cylinder extension area and an upper cylinder retraction area, and an actuator shaft. The actuator shaft has a lower cylinder piston disposed in the lower cylinder, an upper cylinder piston disposed in the upper cylinder, a lower shaft connecting the lower cylinder piston to the upper cylinder piston, and an upper shaft extending from the upper cylinder piston and at least partially externally from the upper cylinder. At least one of fluid flow of the lower cylinder matches fluid flow of the upper cylinder and (1) an internal diameter of the lower cylinder is not equal to the an internal diameter of the upper cylinder and (2) a diameter of the lower shaft is not equal to a diameter of the upper shaft.

One object is to reduce a weight of a fluid actuator. The fluid actuator includes: a cylinder having an inner space and a first mounting portion, the inner space being partitioned into a first fluid chamber and a second fluid chamber, the first mounting portion being disposed on an end portion of the cylinder on an axial direction A side; and a piston rod configured to reciprocate in accordance with pressures in the fluid chambers. A wall portion defining the first fluid chamber in the cylinder is made of an iron-based alloy. A wall portion defining the second fluid chamber in the cylinder is made of an aluminum alloy. The piston rod is made of an iron-based alloy.