A hydraulic actuator to which a limit-adjustable mechanical lock device is applied, comprising: a housing having a first hole; side covers coupled at both sides of the housing, and having holder insertion holes formed to be opened toward the first hole side of the housing, and plugs; a first holder of which one side of the outer peripheral surface is inserted into the holder insertion hole at the plug side of the side cover by screw coupling; a second holder fitted and coupled to the inner peripheral surface of the side cover and having one end thereof screw-coupled to the second hole of the first holder; a locking means into which a rod is inserted so as to be movable in an axial direction at a predetermined distance across the second hole of the first holder and the third hole of the second holder.

The invention relates to shut-off valve for controlling flow of a pressurised gas. The shut-off valve comprising a body defining a passage extending between a gas inlet channel and a gas outlet channel, a sealing element, and an emergency stop mechanism. The sealing element arranged to, in a first position, close the passage, and in a second position, open the passage to allow gas to flow between the gas inlet channel and the gas outlet channel through the passage. The invention also relates to a method for controlling flow of a pressurised gas with a shut-off valve and a method for activating an emergency stop of a shut-off valve.

A linear actuator includes a fixed first end, a second end movable linearly along a central axis of the actuator, an inner cylinder configured to urge axial movement of the second end, and a piston assembly including a piston rod located inside of the inner cylinder. One or more locking pawls are located in pawl openings in the piston rod. The one or more locking pawls are selectably engagable with the inner cylinder to prevent relative motion of the piston rod and the inner cylinder. A lockbolt selectably releases the one or more locking pawls from engagement with the inner cylinder and includes an antilock pin engagable with a pawl opening in the one or more locking pawls to urge the one or more locking pawls away from the inner cylinder with axial movement of the lockbolt.

The present disclosure provides a pneumatically drivable actuator for setting a position of a valve closure element in a valve, comprising a piston, which is moveable in a pressure chamber by influence of a drive gas, and a locking mechanism for mechanically locking the piston relative to the pressure chamber. The actuator further comprises a ventilation device for venting the drive gas from the pressure chamber while the piston is mechanically locked relative to the pressure chamber, such that pressurization of the pressure chamber is prevented. A method of locking a valve closure element relative to a valve body of a valve that is controllable by a pneumatically driven actuator is also disclosed.

A two-stage, fully self-retracting, telescopic fluid actuator suitable for high speed ejection applications comprises a detent 38, 64, 26, which locks a cylinder 6 in an extended position for extension of a piston 3 therefrom. The detent is released by retraction of the piston into the cylinder again, e.g. unspring bias, so that the actuator is fully self-retracting. A locking ball 38 of the detent also serves to latch the piston and cylinder to each other for the first stage of the actuator extension. In an alternative embodiment, cam means (80, 117 FIGS. 10, 11 and 13) and plungers (90, FIGS. 10, 12, 13 and 15) perform the detent and latching functions.

A ram air turbine actuator release device to release a ram air turbine actuator includes a lock bolt releasably engaged to the ram air turbine actuator, a toggle comprising a toggle roller to engage the lock bolt, and a toggle pivot to couple the toggle to the ram air turbine actuator, a hydraulic toggle actuator, including a piston defining a first hydraulic chamber and a second hydraulic chamber, a solenoid valve in fluid communication with the first hydraulic chamber, and a plunger coupled to the piston, wherein a pressure differential between the first hydraulic chamber and the second hydraulic chamber displaces the plunger to rotate the toggle to disengage the toggle roller from the lock bolt.

A hydraulic system for operating an automatic transmission for motor vehicles includes a hydraulic actuator for operating a clutch and a stop valve, whereas the actuator has a pressurizable actuating pressure chamber, which can be closed in a pressure-tight manner by means of the stop valve, such that the clutch pressure is maintained independent of the other pressures of the hydraulic system. The stop valve includes a closure device that is movable by means of a hydraulic control pressure (p_S) into a closed position, in which an actuating pressure chamber port, and thus the actuating pressure chamber, is closed by means of the closure device. The closure device is movable into an open position at least by means of the force of a spring, in which the actuating pressure chamber port is opened. Thereby, the stop valve features a shiftable locking device, by means of which the closure device can be fixed in the closed position.

An actuator system comprising a rotatable lock mechanism defining a path for an actuator pin as the actuator is expanded and retracted, wherein the lock mechanism defines an entry passage through which the pin enters as the actuator extends, a guide surface along which the pin travels from the entry passage as the actuator retracts, a locking recess into which the pin is guided by the guide surface, and an exit passage into which the pin is guided as it is caused to leave the lock recess by extension of the actuator and subsequent retraction; whereby a detent surface is provided to prevent the pin returning back into the lock recess when the actuator is extended to cause the pin to leave the lock recess.

A ram air turbine control valve includes a sleeve, a spool, and a return housing. The sleeve defines a first exit port disposed proximate a first end of the sleeve and defines a second exit port disposed between the first exit port and the first end. The spool is radially contained within the sleeve and is movable between a first position and a second position. The return housing is coupled to the first end of the sleeve and defines a cavity that receives a biasing member that engages the spool.

The disclosure relates to a locking unit, in particular for the parking lock of an automatic transmission, for locking the movement of a piston which is movable by a drive and in particular can be acted upon with pressure or hydraulic pressure, wherein the piston is at least partially mounted in a center section which is at least partially surrounded by a housing.