A valve device that changes the direction of flow of a hydraulic fluid supplied to and discharged from a cylinder mechanism to actuate the cylinder mechanism, the valve device including: a control valve including a main spool axially movable between different positions; a lock valve including a plunger and a pressure chamber; and a selector valve including a selector spool operable in conjunction with the main spool to axially move between different positions, the selector spool being located adjacent to the main spool and having an axis crossing an axis of the main spool.

An actuator assembly including a fail-fix system is provided. The actuator assembly includes an output shaft, an input drive assembly, and a piston assembly. The piston assembly includes a body surrounding a piston moveable within the body. The body defines a first end and a second end opposite thereof between which the piston is moveable within the body. The piston assembly includes a spring disposed at the first end between the body and the piston. The piston assembly includes a friction mechanism disposed at the second end of the piston opposite of the first end. An adjustable area is defined within the body between the second end of the piston and the input drive assembly.

A modular hydraulic device comprising: a housing having a receptacle having a first open end, a second end and a first port, the first port for facilitating an ingress and an egress of hydraulic fluid with respect to the housing; a sleeve configured to be received in the first open end and abut the second end; and an end cap for closing the first open end once the sleeve is inserted in the receptacle; the sleeve having: a body having a fourth lan (L4) positioned in the body for aligning with first port; a main cylinder for holding a main piston for reciprocation about a reciprocation axis; and a first bore portion fluidly coupled to the first lan, the first bore portion for receiving the ingress of the hydraulic fluid and for outputting the egress of the hydraulic fluid; wherein once assembled the main piston is coupled to a cam for facilitating said reciprocation.

A linear actuator system includes a linear actuator including an outer body, an inner body disposed within the outer body, a fluid chamber at least partially extending between the inner body and the outer body, a piston chamber extending at least partially within the inner body, a valve configured to selectively fluidly couple the fluid chamber and the piston chamber to each other, a piston assembly including a piston, a variable volume within the piston chamber that extends between the piston and the valve, and a gas collector assembly including a fluid passageway. The piston assembly is disposed within the piston chamber, wherein a movement of the piston assembly causes a gas separated from a liquid within the variable volume to flow through the fluid passageway, through the valve, and into the fluid chamber.

A method for securing an aircraft landing gear wheel drive actuator in an open position of the wheel, the drive actuator being movably mounted on the landing gear between said open position in which it is remote from the wheel and an engaged position in which it cooperates with the wheel to ensure its rotational drive, a displacement actuator being coupled to the drive actuator to move same between the two positions, and a locking member being provided to lock the drive actuator in the open position. The method includes holding the controlled displacement actuator to move the drive actuator to the open position, while the drive actuator is locked in the open position.

An actuator assembly including a fail-fix system is provided. The actuator assembly includes an output shaft, an input drive assembly, and a piston assembly. The piston assembly includes a body surrounding a piston moveable within the body. The body defines a first end and a second end opposite thereof between which the piston is moveable within the body. The piston assembly includes a spring disposed at the first end between the body and the piston. The piston assembly includes a friction mechanism disposed at the second end of the piston opposite of the first end. An adjustable area is defined within the body between the second end of the piston and the input drive assembly.

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.

A cylinder actuator includes a body assembly and a piston assembly. The body assembly includes a first cylinder nested concentrically within a second cylinder. The piston assembly slides linearly within the first and second cylinders. The piston assembly includes a first piston assembly end and a second piston assembly end. The first piston assembly end includes first and second pistons. The first piston moves within the first cylinder. The second piston moves within the second cylinder. The piston assembly includes first and second piston rods. The first piston rod extends from the first piston through a first end of the first cylinder. The second piston rod extends from the second piston through a first end of the second cylinder. The piston rods are joined at the second end of the piston rod assembly located outside of the first and second cylinders.

A linear actuator system includes a linear actuator including an outer body, an inner body disposed within the outer body, a fluid chamber at least partially extending between the inner body and the outer body, a piston chamber extending at least partially within the inner body, a valve configured to selectively fluidly couple the fluid chamber and the piston chamber to each other, a piston assembly including a piston, a variable volume within the piston chamber that extends between the piston and the valve, and a gas collector assembly including a fluid passageway. The piston assembly is disposed within the piston chamber, wherein a movement of the piston assembly causes a gas separated from a liquid within the variable volume to flow through the fluid passageway, through the valve, and into the fluid chamber.

A shift control device includes a hydraulic circuit and a control unit. The hydraulic circuit is provided with multiple actuation valves. The control unit is configured to switch positions or states of each of the multiple actuation valves in accordance with a shift position command by a shift operation device. The hydraulic circuit is configured to couples a hydraulic oil supply source to one of travel actuators in an automatic transmission in multiple circuit states where the position or the state of at least one of the multiple actuation valves differs.