A hydraulic oil-circuit system and a hydraulic jack are proposed. The hydraulic oil-circuit system includes a hydraulic cylinder, an oil loading chamber, a storage oil chamber and an oil unloading pipeline; a piston is arranged in the hydraulic cylinder and divides the hydraulic cylinder into a first hydraulic oil chamber and a second hydraulic oil chamber; the first hydraulic oil chamber has a first oil port, and the second hydraulic oil chamber has a second oil port; the first oil port and the second oil port are both in unidirectional communication with the oil loading chamber and are both in unidirectional communication with the storage oil chamber; and the oil unloading pipeline connects the oil loading chamber and the storage oil chamber.

Hydraulic bi-directional flow switches are disclosed. A disclosed example apparatus includes a piston disposed in a fluid channel between a first fluid connection and a second fluid connection, where the first and second fluid connections define a fluid pathway for hydraulic steering fluid. The example apparatus also includes a detector to detect a movement of the piston away from a default position of the piston, where the piston is to displace from the default position when the hydraulic steering fluid flows along the fluid pathway.

Provided is a cylinder device capable of preventing rotation unevenness while reducing power consumption and achieving compactification in particular. The present invention is to provide a cylinder device including a cylinder body and a shaft member supported in the cylinder body, the cylinder body being provided with a rotation port that communicates with an outer circumferential surface around the shaft member and rotates the shaft member based on a supply and discharge of a fluid. Thus, it is possible to prevent rotation unevenness while reducing power consumption and achieving compactification.

Methods, apparatus, systems and articles of manufacture are disclosed that produce a pneumatic actuator end cap having an integral volume booster. An example pneumatic actuator end cap includes a first cavity to provide a first fluid passageway to receive a pressurized fluid from a source external to the pneumatic actuator end cap, a second cavity to provide a second fluid passageway to route the pressurized fluid to an internal chamber of a pneumatic actuator in which a piston is disposed, and a third cavity containing a fluid valve to control a flow of the pressurized fluid between the first fluid passageway and the second fluid passageway.

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 actuator is provided. The actuator includes a first body defining an interior, a second body disposed about the first body and defining space between an exterior of the first body and an interior of the second body, a plunger including a head sealably disposed in the interior and a rod connected to the head and sealably extended through the first and second bodies and first and second fluid systems. The first fluid system is insulated from the space. A first fluid is moved relative to the interior for causing the plunger to extend or retract by way of the first fluid system. A second fluid is moved through the space by way of the second fluid system.

Provided is a cylinder device capable of preventing rotation unevenness while reducing power consumption and achieving compactification in particular. The present invention is to provide a cylinder device including a cylinder body and a shaft member supported in the cylinder body, the cylinder body being provided with a rotation port that communicates with an outer circumferential surface around the shaft member and rotates the shaft member based on a supply and discharge of a fluid. Thus, it is possible to prevent rotation unevenness while reducing power consumption and achieving compactification.

An electric fluid pressure cylinder is provided with: a driving unit integrally provided with an electric motor, a pump configured to discharge working oil by being driven by the electric motor, and a tank; a hydraulic cylinder configured to be extended and contracted by the working oil supplied from the driving unit; and a first hose pipe and a second hose pipe configured to guide the working oil between the driving unit and the hydraulic cylinder. The driving unit is further provided with: a valve block configured to control the flow of working fluid between the fluid pressure cylinder and the pump; and a connecting plate attached to the valve block and formed with a connecting port to which the pipe member is connected, the connecting port being configured such that the working fluid supplied to and discharged from the fluid pressure cylinder passes through the connecting port.

A rotary actuator where a thrust bearing ring is positioned at an inside of a tube assembly accommodating oil, thereby reducing abrasion and damage caused by rolling friction and improving rotary power of an axle load by increasing hydraulic pressure of a piston. The rotary actuator includes the tube assembly, a piston, an axle load assembly, and a thrust bearing ring. The tube assembly is provided with a tube spiral portion where a spiral is formed at an inner circumference surface, and is formed of a first passage where oil flows into and out and a second passage spaced apart from the first passage by a fixed distance.

A hydraulic valve arrangement (1) is provided comprising comprising a supply port arrangement having a high pressure port (2) and a low pressure port (4), a working port arrangement having two working ports (6, 7), a first valve (13) arranged between said high pressure port (2) and said working port arrangement (6, 7), a second valve (14) arranged between said low pressure port (4) and said working port arrangement (6, 7), a controller (19) for controlling said first valve (13) and said second valve (14), said controller (19) having an input connection (20) for receiving a signal of an operator input device, and a regenerative flow path which can be established by means of at least one of said first valve (13) and said second valve (14). The function of such a hydraulic valve arrangement should be enhanced. To this end said controller (19) said controller interrupts said regenerative flow path when a feed pressure at said working port arrangement (6, 7) exceeds a predetermined pressure level.