A stepper motor driven actuator system is provided. The system includes a stepper motor, a cam, and a gearbox system. The gearbox system operatively connects the stepper motor to the cam. The cam rotates in response to stepping of the stepper motor. The system also includes a valve having a control piston located therein. The control piston is configured to translate in response to rotation of the cam. The system further includes a rotary actuator. The rotary actuator is fluidly connected to the valve, and the rotary actuator is configured to rotate the cam in response to translation of the control piston.

A process valve apparatus (10), including: a process fitting (1) with a valve member (2), a pneumatic valve drive (3) for actuating the valve member (2), and a control device (4) with a pneumatic valve device (5) for pneumatically actuating the valve drive (3), wherein the control device (4) is configured to carry out a partial stroke test and, within the partial stroke test: to actuate the valve drive (3) pneumatically by means of the valve device (5), so that the valve drive (3) sets the valve member (2) in a test movement sequence in which the valve member (2) performs a first test movement from a first position (x1) to a second position (x2) and a second test movement from the second position (x2) back to the first position (x1), to detect pressure information related to the pneumatic actuation of the valve drive (3) and, taking into account the pressure information, to determine status information indicating the functioning and/or the wear of the process valve apparatus (10).

An electrohydraulic system includes an output shaft, a hydraulic piston, and a preload device. The output shaft rotationally drives the valve and extends along a first axis. The hydraulic piston extends along a second axis perpendicular to the first axis, is actuated by a pressure medium, and rotates the output shaft. The preload device stores energy via preloading of an elastic element, which extends along a third axis, by a hydraulic cylinder and to transmit the energy to the output shaft in the event of a fault. The hydraulic piston is guided into first and second cylinder housings, and at least one of the cylinder housings is connected to the hydraulic cylinder. A check valve is arranged between the cylinder housing and the hydraulic cylinder, and is configured to decouple the preload device from the hydraulic piston, the blocking direction going from the hydraulic cylinder to the cylinder housing.

An actuator is configured to couple with a controlled member and includes first and second pistons disposed in respective internal chambers. The first piston may be moveable between first and second positions. The second piston may be moveable between third and fourth positions. The second piston may be configured not to engage the first piston when the second piston is disposed at the third position. The second piston may be configured to move the first piston to the second position as the second piston moves from the third position to the fourth position. A resilient member may be disposed to resiliently urge the second piston toward the fourth position.

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.

A pressure medium cylinder (1) for moving a toothed bar (3), comprising a toothed bar (3) on at least one side of which is formed a toothing (4). Inside the toothed bar (3), a cavity (6, 6a, 6b) is formed, extending to at least one end (7a, 7b) of the toothed bar. The pressure medium cylinder (1) further comprises a longitudinal structure (8, 8a, 8b), the longitudinal structure (8, 8a, 8b) and the toothed bar (3) being adapted movably in relation to each other, and the longitudinal structure (8, 8a, 8b) is adapted at least partly inside said cavity (6, 6a, 6b). The toothed bar (3) and longitudinal structure (8, 8a, 8b) are adapted in a sealed manner in relation to each other so that the toothed bar and the longitudinal structure are movable in relation to each other by the effect of a pressure medium.

A rack assembly for a rack and pinion gear system may comprise: a rack housing; and a rack disposed within the rack housing, the rack and the rack housing at least partially defining a first hydraulic chamber disposed between a first side of the rack and the rack housing, a second hydraulic chamber disposed between a second side of the rack and the rack housing, a third hydraulic chamber disposed within the rack proximal the first hydraulic chamber, and a fourth hydraulic chamber disposed within the rack proximal the second hydraulic chamber.

The present disclosure relates to the field of fluid process systems and discloses a manifold system for fluid delivery. The system comprises a first set of Solenoid Operated Valves (SOVs), a second set of SOVs, a plurality of isolating valves, at least one first shuttle valve, and at least one redundant shuttle valve. Each set of SOVs includes at least two SOVs arranged in parallel. The SOVs together form a series-parallel redundancy. Each isolating valve is coupled to an SOV and facilitates hot swapping of that SOV. The redundant shuttle valves provide redundancy to the first shuttle valve and facilitate the flow of a fluid from each of the first set of SOVs to each of the second set of SOVs, thereby promoting system safety and availability.

A rotary actuator is equipped with an end cover disposed on one end surface of a cylinder main body, a first plug that is engaged with a wall surface constituting an opening on another end side of a first cylinder hole, and a second plug that is engaged with a wall surface constituting an opening on another end side of a second cylinder hole. A first port communicating with a first front cylinder chamber and a second rear cylinder chamber, and a second port communicating with a second front cylinder chamber and a first rear cylinder chamber are formed in the end cover.

A modular actuator assembly which can be used for partial stroke testing of a valve, the assembly having a force module and a tandem piston module. The force module has a primary piston and piston rod interconnected to a shaft which is movably mounted therein. The tandem piston module is connected to the force module and has a tandem piston and piston rod. An indicator plate is connected to the piston rod and is selectively positionable on the tandem piston rod. The tandem piston rod extends into the force module and acts as a pneumatically engaged hard stop for preventing spurious travel of the primary piston and hence spurious valve travel.