A position indicator for a rotary drive of a process valve is proposed, which can be mounted on a rotatable indicator shaft of the rotary drive and which has a base indicator element and an additional indicator element, wherein the additional indicator element can be positioned and fixed about a vertical axis in different angular positions. On the base indicator element a plurality of base indicator markings are arranged, while the additional indicator element has an additional indicator markings. In order to indicator various visually perceptible valve-type symbols, the additional indicator element can be positioned, inter alia, in at least one cover angle position, in which it covers at least one base indicator marking, but leaves at least one further base indicator marking uncovered, which together with the always visible additional indicator marking represents the valve-type symbol.

Provided is an electromechanical-linkage hydraulic control gate valve actuator. The actuator includes a hand-operated speed-increasing gearbox assembly and a bidirectional throttle valve. In the present invention, a motor is driven to rotate through the hand-operated speed-increasing gearbox and thus a hydraulic system is driven to finally open and close a gate valve. An opening and closing speeds of the gate valve can be regulated and controlled through the bidirectional throttle valve. The present invention drives the motor through the hand-operated speed-increasing gearbox under emergency conditions such as repair and power failure, thereby controlling to open and close the gate valve. Meanwhile, a hydraulic system respectively regulates the speeds of two states of opening and closing through a bidirectional throttling technique, so as to effectively eliminate a water hammer phenomenon. The present invention has simple structure, light weight and modular installation, and enhances safety and reliability.

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 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.

A pneumatic system for operating a drive for a windshield wiper for a rail vehicle, wherein the windshield wiper drive has a piston guide device that has a first connection and a second connection opposite the first connection. At least one piston in the piston guide device carries out linear movements in opposite directions along the main direction of extension of the piston guide device to bring about an alternating rotational movement of the wiper shaft. The pneumatic system has a supply connection for a compressed air supply, wherein the supply connection is connected to the first connection via a first normal operation connection line and a first emergency operation connection line arranged parallel thereto and to the second connection via a second normal operation connection line and a second emergency operation connection line arranged parallel thereto.

A particle blast apparatus includes a metering portion, a comminutor and a feeding portion. The metering portion and comminutor may each be configured to provide uniformity in the discharge of particles. The metering portion controls the particle feed rate, and may include a rotor, which may have V or chevron shaped pockets. The comminutor includes at least one roller which may be moved between and including a position at which the gap of the comminutor is at maximum and a position at which the gap is at minimum. The metering portion may discharge particles directly into the feeding portion without a comminutor being present. The comminutor may receive particles directly from a source of blast media without a metering portion being present.

A hydraulic disc coupling (1) for a system distributing torque between the left and right wheels and/or the front and rear axles of a vehicle is provided. A coupling piston (6) is configured to be mechanically locked by an integrated locking arrangement (23), when the coupling piston (6) is actuated to act on the disc package (8), such that the coupling remains engaged whereby the input (2) is connected to the output (7) of the coupling (1) without hydraulic pressure acting on the coupling piston (6). Unlocking of the integrated locking arrangement (23) is provided by again actuating the coupling piston (6).

The invention relates to a fluid-actuated rotary actuator comprising a housing having a tubular body extending in an axial direction, in which is provided a drive piston assembly for driving a rotatably mounted output shaft, which extends perpendicular to the axial direction through the tubular body and the axial end of which is routed out of the tubular body at an upper wall section of the tubular body, further comprising a magnet assembly associated with the axial end of the output shaft and receiving a rotary movement of the output shaft, and further comprising a position feedback device configured to detect the magnetic field generated by the magnet assembly and to provide, in accordance with the detected magnetic field, a position signal corresponding to a position of the output shaft, wherein the position feedback device is located in a receptacle chamber formed in the upper wall section of the tubular body.

A fluid-actuated rotary drive with a housing in the form of a tubular body, which has a piston space extending in an axial direction of the housing, in which is movably guided a drive piston assembly for driving a rotatably mounted output shaft, wherein the housing has at one axial end an end face, which is open towards the piston space, with at least one mounting section suitable for the attachment of a housing cover, and with a function module assembly which includes an electronic assembly for monitoring, control and/or regulation of the rotary drive and/or a control valve assembly for actuation of the rotary drive, wherein the function module assembly is placed on the end face and secured by means of at least one mounting section.

Provided is an energy storage structure, comprising a housing and a piston. An accommodating cavity and a piston cylinder part communicating with each other are arranged within the housing. The piston is slidably and sealingly arranged within the piston cylinder part for transferring impact energy. A self-pressure of an energy storage medium, arranged within the accommodating cavity and the piston cylinder part, acts on the piston, tending to push the piston to move. An energy storage structure provided by the present invention has a simple structure, is convenient for use, and can ensure that a thrust or impact force remains unchanged or slightly changes during operation, to achieve stable release of potential energy. Moreover, the adjustment of the thrust or impact force can be achieved by changing the temperature of the energy storage medium in the accommodating cavity, thereby achieving change in total impact energy of the energy storage structure.