Abstract: A sleeve for a valve assembly has an inside surface having an interior area and a first cylindrical section extending from a first axial end and a second cylindrical section located between the first cylindrical section and second axial end. A conical interior seating surface extends between the first and second cylindrical sections. The conical interior seating surface is metallic. The sleeve includes a groove that extends circumferentially around and radially outward in the first cylindrical section. The groove extends axially away from the conical interior seating surface towards the first axial end. The sleeve has one or more ports extending radially through the first cylindrical section proximate the groove and are spaced apart from the groove by a lip formed by the first cylindrical section. The lip extends a predetermined axial distance between the groove and the port. The lip extends around the first cylindrical section and radially inward.

Abstract: A main stop valve includes: a hydraulic cylinder; a piston arranged in a hydraulic cylinder; a valve rod connected to the piston; and a valve body connected to the valve rod and configured to block a steam passage. The main stop valve further includes: a pilot cylinder having a communication port in fluid communication with the hydraulic cylinder; a rod connected in parallel with the valve rod and configured to be inserted from one end of the pilot cylinder; a sliding ring provided on the rod; and a pilot sleeve configured to be slidably fitted into an inner surface of the pilot cylinder and slidably fitted into an outer peripheral surface of the sliding ring in a section between the one end of the pilot cylinder and the communication port.

Abstract: A valve actuator for moving a valve element includes an actuator body, an opening piston, a closing piston, a first lost-motion link, and a second lost-motion link. The actuator body has an inner surface, a vent opening, a full-open pneumatic passageway, and a full-closed pneumatic passageway. The opening piston is movably disposed within the piston chamber between the vent opening and the full-open pneumatic passageway. The closing piston is movably disposed within the piston chamber between vent opening and the full-closed pneumatic passageway. The first lost-motion link is coupled to the opening piston and is operable to selectively rotate the valve element. The second lost-motion link is coupled to the closing piston and is operable to selectively rotate the valve element.

Abstract: The invention relates to agate valve hydraulic actuator, said actuator comprising a cup shaped sleeve (9) which is operably coupled to an opening or closing element (5) of the gate valve (2), the actuator further comprising a movable primary piston (13) arranged within a primary cylinder (12) arranged at the inside of the cup-shaped sleeve (9), said primary piston (13) being con figured to move the sleeve (9) and hence said opening and closing element (5) towards an open or closed position of the gate valve (2) by a force applied to the primary piston (13).

Abstract: 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.

Abstract: A pneumatic system for operating a hydraulic valve is provided. The system may include: a first piston set; a first connector attached to the first piston operably connecting the first piston; a first spring biasing the first piston to move in an axial direction; a second port in the first housing; a second piston set with in a second cavity defined by a second housing; a second connector attached to the second piston, a second spring biasing the second piston to move in an axial direction; a first port in the second housing; and a second port in the second housing configured to provide fluid communication with in the second cavity at a second end of the second piston.

Abstract: The current application discloses methods and systems for generating mechanical tube waves in fluid filled boreholes penetrating subterranean formations. In one embodiment, the system of the current application comprises an energy storage chamber; a fast operating valve connected to the energy storage chamber; a pipe connected to the valve and extending to the liquid-filled borehole; wherein the energy storage chamber contains a first pressure that is substantially different from a second pressure in the pipe so that a fast operation of the valve generates a tube wave in the pipe.

Abstract: A compressed-air supply device for commercial vehicles is provided. The compressed-air supply device may be connected electrically to an electronic control device that may actuate at least one control valve. The control valve has at least one inlet, one ventilating connection and one outlet. The compressed-air supply device has a control line which is connected to the control valve outlet and may be connected to a control inlet of a compressor and/or an inlet of a regeneration valve, has a supply line via which compressed air may be guided to the control valve inlet, and has a ventilating line connected to the control valve ventilating connection. The control valve may be ventilated via the ventilating line, and is configured such that at a predefined opening pressure in the supply line it pneumatically produces a fluid-conducting connection between the inlet and the outlet such that the control line is ventilated.

Abstract: A ball valve assembly is provided. The ball valve assembly comprises a pipe section having an axial bore for enabling fluid flow therethrough in use; a valve ball having an internal conduit, the valve ball being mounted within the pipe section and being for rotation with respect to the pipe section between an open position in which fluid within the axial bore may flow through the internal conduit and a closed position in which the internal conduit is inaccessible to fluid within the axial bore; a device configured to rotate the valve ball, the device being located radially outside the axial bore; and an encapsulation positioned to receive the valve ball and having portions located radially between the pipe bore and the device configured to rotate the valve ball, such that the encapsulation prevents fluid within the axial bore from accessing the device configured to rotate the valve ball.

Abstract: Embodiments of the present disclosure are directed toward a second pneumatic actuator configured to couple to a gate valve, wherein the second pneumatic actuator is configured to apply a supplemental force to a gate of the gate valve, wherein the supplemental force supplements an actuating force of a first actuator of the gate valve.

Abstract: A fluid-operated actuating drive on a valve comprising a base unit (2) having an electro-fluidic signal converter and a fluidic controller and at least one linear actuator (4) that can be actuated using the fluidic controller, wherein the gate (11) of the linear actuator is directly or indirectly coupled to the inlet of the valve. A control unit (22) is connected to a signal input of the base unit, wherein the signal output is connected to the electro-fluidic signal converter. The actual value signal of a measurement transducer (24) associated to the valve is fed back to the control unit. A fluidic internal control circuit (27) is arranged functionally between the signal input and the at least one linear actuator, preferably downstream of the electro-fluidic signal converter.

Abstract: The present invention provides a cutoff valve control apparatus capable of predicting a failure of devices therein with a failure diagnosis based on an operation test when the cutoff valve control apparatus is set. The cutoff valve control apparatus includes a judging device to judge a normal state or an abnormal state of the apparatus based on a pressure characteristic of an internal pressure of a cylinder measured with a pressure sensor when an air is supplied to the cylinder of an air cylinder from an air supply source, and a memory device storing beforehand the pressure characteristic of the internal pressure of the cylinder of an initial normal operation of the apparatus and the pressure characteristic of a failure prediction boundary.

Abstract: A fuel staging system comprises a splitter valve arranged to split an input fuel stream into a pilot fuel stream and a main fuel stream, the splitter valve comprising a spool slidable within a bore, the spool and bore together defining first and second control chambers, the fluid pressures in which determine the position occupied by the spool, the system further comprising a control line which, in use, controls fuel delivery through a plurality of main burners, the fluid pressure in the control line being a combination of the fluid pressures in the first and second control chambers.

Abstract: A control valve includes a signal pressure passage that transmits a pilot pressure in first and second pilot chambers as a signal pressure of another device, and first and second connecting grooves that connect the first and second pilot chambers to the signal pressure passage when a spool is in a neutral position. When the pilot pressure is led into the first pilot chamber such that the spool moves, the first connecting groove connects the first pilot chamber to the signal pressure passage while the second connecting groove separates from the signal pressure passage. When the pilot pressure is led into the second pilot chamber such that the spool moves, the second connecting groove connects the second pilot chamber to the signal pressure passage while the first connecting groove separates from the signal pressure passage.

Abstract: A driving and adjusting device of a passive shuttle-type shut-off valve is provided. The problems of a big valve body structure size, a non-random angle installment, a single drive mode, low stability and reliability, a high temperature and poisonous material entering into the driving and adjusting device and unadjustable on-off speed and low volume in the prior device are solved. A main body (33) is connected with an upstream pipe (1) and a downstream pipe (3). A pressure port (2) on the upstream pipe (1) is connected with the driving device. A double acting cylinder (34) is provided in a valve sleeve (21). The left and right chambers of the double acting cylinder are connected with the valve clack (24). The driving device is composed of a regulating valve, a directional valve, a check valve, a boost-insulation valve and an accumulator (18). It can select the drive mode and adjust the on-off speed and the flow volume of the valve.

Abstract: A hydraulic actuating device for a sliding stem control valve assembly is mounted between a control valve and an actuator housing. The hydraulic actuating device is connected to one of a control valve stem, an actuator stem, and a stem connector and the hydraulic actuating device moves either the control valve stem, the actuator stem, or the stem connector in response to varying hydraulic pressure within the hydraulic actuating device. The hydraulic actuating device may be used to override an actuator of the sliding stem valve during emergency operations, or to provide a backup actuator in the case of a primary actuator malfunction.

Abstract: Rotary valve actuators having partial stroke damping apparatus are described herein. An example rotary valve actuator described herein includes a housing containing a first piston and a second piston opposite the first piston, where the pistons move in opposite directions to rotate a shaft of the rotary valve actuator. A damper is operatively coupled to at least one of the first piston or the second piston to slow the movement of the piston for only a portion of a stroke of the rotary valve actuator.

Abstract: A valve assembly includes a valve body having a valve bore. A valve member is slidably disposed within the valve bore between first and second stop positions. First and second valve elements of the valve member have first and second sealing surfaces equally angled with respect to a valve member longitudinal axis. Each of the first and second sealing surfaces is oriented parallel with conical shaped first and second seat surfaces. Both first and second seat surfaces are equally angled with respect to the longitudinal axis and have an adjustable spacing such that the first sealing surface contacts the first seat surface and the second sealing surface contacts the second seat surface simultaneously in the first stop position.

Abstract: A control valve includes a signal pressure passage that transmits a pilot pressure in first and second pilot chambers as a signal pressure of another device, and first and second connecting grooves that connect the first and second pilot chambers to the signal pressure passage when a spool is in a neutral position. When the pilot pressure is led into the first pilot chamber such that the spool moves, the first connecting groove connects the first pilot chamber to the signal pressure passage while the second connecting groove separates from the signal pressure passage. When the pilot pressure is led into the second pilot chamber such that the spool moves, the second connecting groove connects the second pilot chamber to the signal pressure passage while the first connecting groove separates from the signal pressure passage.

Abstract: A valve assembly having a pressure dead band includes a first valve or sleeve slidably disposed within a valve body. A second valve is partially slidably disposed within the first valve and partially slidably disposed in the valve body. A plurality of fluid passages communicate with the valve assembly and provide a first flow of hydraulic fluid and a second flow of hydraulic fluid. A lower threshold of the pressure dead band is defined by the pressure on the combination of the first area of the first valve and the first area of the second valve required to balance the resultant force developed on the second area of the second valve. An upper threshold of the pressure dead band is defined by the pressure on the first area of the second valve required to balance the resultant force developed on the second area of the second valve.

Abstract: A valve includes a housing defining a bore having an inlet and extending along a longitudinal axis. A head is attached to the housing and defines a head passage having an outlet. A piston is disposed within the bore and includes a piston passage extending through the piston along the longitudinal axis. The piston is moveable between a closed position in which a sealing end of the piston abuts a seat of the head to close fluid communication through the piston passage and an open position in which the sealing end of the piston is axially spaced along the longitudinal axis from the seat of the head to permit fluid communication through the piston passage between the inlet and the outlet. The housing defines an equalizing chamber in fluid communication with the head passage for damping movement of the piston.

Abstract: A system for positioning a device such as a valve with a mechanical input using a fluid operated actuator, a mechanical position feedback member coupled to a feedback element of the fluid operated actuator and an activation fluid valve. The fluid operated actuator has an output coupled to the mechanical input of the valve, a feedback element for mechanically indicating a position of the valve, and inputs for actuating fluid, such that fluid at the inputs causes the fluid operated actuator to move in opposing directions. The activation fluid valve has outputs coupled to the inputs of the fluid operated actuator, a first opposing force input coupled to the mechanical position feedback member and a second opposing force input coupled to a control input force. The position of the activation fluid valve is controlled by a balance between the force from the mechanical feedback member and the control input force.

Abstract: The invention relates to a valve device comprising a valve housing (2) and a valve piston (4) arranged in an axially displaceable manner in a piston bore (3) of the valve housing (2), via which valve piston a first load connection (A) and a second load connection (B) can alternately be connected to a pressure connection (P) and to a tank connection (T1, T2) by the action of a first solenoid magnet (5) and a second solenoid magnet (6), a pilot control unit (7) being provided, which comprises a first pilot control chamber (8) that pressurizes a first piston back side (9) of the valve piston (4) and a second pilot control chamber (10) that pressurizes a second piston back side (11) of the valve piston (4), the first and second pilot control chambers (8, 10) being connectable via a respective fluid-conducting connection (12, 13) to the pressure connection (P), a first pilot control piston (14) and a second pilot control piston (15) being provided, which release or close a fluid-conducting connection (16, 17) betw

Abstract: A proportional control pneumatic cylinder as an air actuator device for a hydraulic pump valve having a valve spool moving in a bore in a valve housing. The device having an actuator housing attachable to the valve housing and having a bore carrying a piston coaxially secured to an end of the valve spool. The device provided with spaced openings in the actuator housing which communicate with the bore therein to introduce air to act on opposite sides of the piston, and factory pretensioned biasing means for normally urging the piston and spool to a center closed position. Surface areas on opposite sides of the piston are approximately equal so that piston movement is approximately proportional to movement of an actuating lever of an air supplying pneumatic control valve over the majority of the range of travel of the actuating lever for both raised and lowered positions.

Abstract: A valve actuator is provided for use in conjunction with a drive motor and a valve. In one embodiment, the valve actuator includes a housing assembly, a first power screw rotatably mounted in the housing assembly and configured to be rotated by the drive motor, a first rack translatably mounted in the housing assembly, and a pinion rotatably mounted in the housing assembly and mechanically linked to the valve. The first rack is threadably coupled to the first power screw and is configured to move linearly as the first power screw rotates. The pinion engages the first rack and is configured to rotate as the first rack moves linearly to move the valve to a desired position.

Abstract: A valve for controlling pressure in a system is provided. The valve includes a housing, a servo spool and a piston positioned within the housing with the piston and the servo spool being movable relative to each other. The piston defines a first orifice configured to communicate with a supply of pressurized fluid and a second orifice configured to communicate with a portion of the system exterior to the valve. A first chamber is arranged such that force due to fluid pressure in the first chamber is configured to move the piston in a first direction. The first chamber includes a third orifice configured to communicate with a controlled pressure in the system. A second chamber is at least partially defined by the housing and the piston and includes a fourth orifice configured to communicate with a low pressure fluid source. A biasing element is arranged in the second chamber.

Abstract: A percussion apparatus driven by a pressurized incompressible fluid includes a body with two coaxial bores for slidably mounting of a tool, and separately slidably mounting a striking piston having a stepped configuration. A control device varies a stroke of the striking piston between a long and a short stroke, and is connected to the directional flow valve and to a bottom chamber of the piston cylinder. The control device includes a cylinder in which a spool is mounted. A first face of the spool is situated in a first chamber permanently subjected to a determined pressure, and a second face of the spool is situated in a second chamber connected to the braking chamber for controlling the varying of the stroke of the striking piston.

Abstract: A microvalve device for controlling the supply of pressurized fluid to a load in a fluid circuit, and having multiple internal fluid conduits for providing pressure feedback.

Abstract: A valve assembly (10) to regulate the flow of a refrigerant. The valve assembly (10) includes a movable valve member (25) to which there are attached two pistons (29 and 30). A refrigerant under pressure is applied to the pistons (29 and 30) to cause movement of the movable valve member (25) to connect or disconnect pipes (17 and 18) through which the refrigerant is to flow.

Abstract: A controlled pressure release valve controls the gas flow in high-pressure systems. The valve includes a valve body, a slidable spool, a primary flow passage, a first and second chamber, a first and second spring, a first and second passages, and a valve actuator. The valve body has a gas inlet and a gas outlet and houses the slidable spool. The slidable spool has a first end and a second end, and is slidable between a first position and a second position. The primary flow passage connects the gas inlet and the gas outlet and increases with lineal movement of the slidable spool. The first chamber is located adjacent the first end of the slidable spool and a second chamber is located adjacent the second end of the slidable spool. The sliding spool is biased toward the first position by a gas pressure applied by the second chamber and the second spring.

Abstract: A valve assembly has a valve body having an inlet section for a pressurized fluid and an outlet. A piston is movable within the valve body between an open position and a closed position blocking fluid communication. The piston has an end section, a sealing section and a middle section located between the end section and the sealing section. A cavity receives the piston within the valve body. The cavity has a superior chamber, an intermediate chamber, and an inferior chamber. A spring within the superior chamber exerts a spring force onto the piston to urge the piston towards the open position. An actuator device provides upon actuation for a first flow of fluid outside the cavity from the inlet section to the superior chamber. The first flow causes a pressure within the superior chamber to increase until it is about the same as the pressure within the container so that the spring force moves the piston to the open position.

Abstract: A percussive device and method having, inside a machine housing (3), a reciprocally moveable percussive piston (2), the movement of which is controlled by a control valve (5), which is arranged to alternatively connect a chamber to a pressure source and to low pressure in dependence on a signal corresponding to the axial position of the percussive piston, and a valve (16) arranged to allow adjustment of the axial position of the percussive piston at which the signal is transmitted, by opening and blocking of a connection between one or more control channels (10, 11, 12, 13) and the control valve.

Abstract: A valve of the invention includes a valve body having an inlet, an outlet, and a flow passage connecting the inlet and outlet, the inlet, the outlet and the flow passage being in general axial alignment within the valve body. A valve seat surrounds the flow passage and a valve closure member is movable towards and away from the valve seat to close and open the valve respectively. The valve closure member is a poppet-type closure member axially mounted to a stem. The stem has a plurality of pistons spaced apart along the length thereof, and the valve body has a plurality of cylinders fixed relative thereto, the pistons each being slidable in a respective cylinder. The valve closure member is movable by varying the pressure in the cylinders. Preferably each of the cylinders has an outlet port through a wall thereof which is exposed when the closure member has moved towards or into a fully open position, pressure within said cylinders dissipating through those outlet ports when the outlet ports are exposed.

Abstract: A cooling air flow regulating device for controlling the flow of cooling air to an air bearing may comprise a housing with a piston and a spring disposed within. When the pressure of the cooling air is high, the piston is forced out of the path of the cooling air and into an open position. As the pressure of the cooling air decreases, the spring forces the piston back into the path of the cooling air, effectively blocking the flow of cooling air to the air bearing. The cooling air flow regulating device of the present invention may be useful for controlling the cooling of air bearings in turbochargers of turbocharged engine, where at low engine speed, cooling air is not required for air bearings. Methods for using the cooling air flow regulating device of the present invention are also provided.

Abstract: A valve for controlling fluid flow in a fluid system is disclosed. The valve includes a housing, a servo spool, and a piston. The servo spool defines a spiral groove and a spiral land. The piston defines an orifice configured to provide flow communication to a supply of pressurized fluid and an orifice configured to provide flow communication to a portion of the fluid system exterior to the valve. The valve further includes a main spool operably coupled to the piston. The main spool is configured to control flow of fluid in the fluid system. The spiral groove and spiral land are configured such that angular displacement of the servo spool results in a force imbalance on the piston, thereby moving the piston and the main spool in one of a first direction and a second direction.

Abstract: A pilot controlled pulse valve has a valve spool releasably held in both terminal positions by a latching device. The latching device comprise a permanent magnet holding the valve spool by magnetic force. To set the terminal or end position the permanent magnet has an abutment placed to the fore of it. In order to protect the permanent magnet against damage the abutment bears against the valve housing independently of the permanent magnet.

Abstract: A valve apparatus and pneumatically driven diaphragm pump incorporating same having a valve body having a longitudinal axis and an actuator having an axis with a first end and a second end. The first and second ends have first and second diaphragms, respectively, disposed thereon and located transversely to the axis of the actuator. Upon inserting the actuator into the valve body, the first and second diaphragms define wall portions of first and second chambers at the first and second ends of the axis of the actuator, respectively, and a chamber defined between the diaphragms.

Abstract: Disclosed is a flow control valve capable of controlling a flow amount of air, gas or fluid inside a pipe. The flow control valve has a relatively simple structure, which can reduce manufacturing expenses, minimize malfunction and wrong driving, and allow a rapid repair and replacement of components.

Abstract: A sliding spool valve (1) is provided for controlling flow of fluid especially between an inlet (2) at a relatively high pressure and an outlet (6) at a relatively low pressure. Wherein the spool valve is reciprocally displaced between open and closed positions by hydraulic action of the transmitted fluid.

Abstract: The purpose of this invention is to provide an actuator for valve driving without enlarging its size, without increasing the cost, and without reducing the pressure receiving area of the pistons.

Abstract: A dirty fluid valve for sealing high differential fluid pressures in a drilling environment and methods for using such a valve is disclosed. One embodiment of the valve includes a seal cartridge having several openings for directing a fluid path through the cartridge, a spring connected at one end of the seal cartridge and extending through the fluid path, and a seal member connected to the other end of the spring. The seal is actuatable between an open position and a closed position so that it covers one of the openings in the seal cartridge when it is in the closed position, thereby sealing off the fluid flow through the seal cartridge fluid path. The spring provides a pre-loading force to the seal member so that the seal member always has sufficient contact with the surfaces surrounding the opening that the seal covers.

Abstract: A double valve flusher includes a body, a separating plate, an upper and a lower valve base, a movable valve, a film valve, a fixing member, and an electromagnet. An upper leak room is formed between the film valve and the upper valve base. A leak room is formed between the separating plate, the lower valve base and the movable valve contained in a chamber in the body. The upper leak passageway in the upper leak room and the upper valve base is blocked or opened by the core of the electromagnet, thus controlling the film valve in disfiguring to block or open the leak passageway of the leak room and the lower valve base. Then the movable valve is controlled to move up and down to flush or stop flushing water into a urinal where this flusher is positioned.

Abstract: The present invention is an apparatus for storing and delivering a low vapor pressure process chemical to a process tool for semiconductor fabrication, comprising: a) a bulk container for storing the process chemical; b) a process container for delivering the process chemical to the process tool; c) a first manifold for delivering process chemical from the bulk container to the process container; d) a solvent container containing a quantity of solvent, and; e) a second manifold for delivering the process chemical from the process container to a process tool. A process for using the apparatus is also contemplated.

Abstract: A valve actuator assembly is provided for selectively opening and closing a valve. The valve actuator assembly includes a primary motor and secondary motor both operatively coupled to an output shaft and adapted to receive valve position commands and operable, in response thereto, to selectively drive the output shaft in a valve open or close direction and a tertiary motor adapted to receive a flow of pressurized air and operable, in response thereto, to drive the output shaft in a valve close direction.

Abstract: A fluid control valve for a pipeline pig includes a main valve and a mechanism for operating the main valve. The main valve comprises a valve body communicated to a fluid pipe, a main valve core movably disposed in the inner chamber of the valve body, and a main valve stem connected to the main valve core. The operating mechanism includes a hydrocylinder, which comprises a piston disposed in the cylinder, and a piston rod connected to the piston. The piston rod is transmissibly connected with the main valve stem so as to drive the main valve core by the main valve stem. A valve device includes a pilot valve, positioned in the pipeline which communicates the fluid pipe with the hydrocylinder, and an operator for controlling the actuation of the pilot valve so as to enable the piston to move reciprocally by the pressure of fluid in the fluid pipe.

Abstract: A closure member for a tubing hanger which is suspended in a tubing spool and which comprises an elongated body having an annulus bore that extends generally longitudinally therethrough, the annulus bore comprising at least a first branch which is in fluid communication with a second branch. The closure member comprises a gate cavity which is in fluid communication with both the first branch and the second branch, a gate which is movably positioned in the gate cavity and which includes a first flow port that is connected to a second flow port, and an actuator for moving the gate between an open position, in which the first flow port is aligned with the first branch and the second flow port is in fluid communication with the second branch, and a closed position, in which the first flow port is offset from the first branch, wherein the actuator is disposed at least partially within a conduit that extends generally axially through the tubing hanger.

Abstract: A two-stage valve for controlling the flow of fluid from a pressurized fluid supply with an upper main body including a cavity with a contoured inner surface; a lower main body with at least one flow exhaust passage forming a primary flow path through the two-stage valve; a pre-stressed diaphragm sandwiched between the upper and lower main bodies, and pressure control capability for controlling the pressure in the cavity. A first valve opens and closes the flow of gas from the pressurized gas supply to the cavity. A second valve allows the pressure in the cavity to exhaust to the environment. Raising and lowering of the pressure in the cavity causes the pre-stressed diaphragm to open and close the flow of gas from the pressurized gas supply through the primary flow path of the two-stage valve. The design is suitable as a microvalve using Micro-Electro-Mechanical Systems (MEMS) concepts.

Abstract: A fuel injection system for an internal-combustion diesel engine has a fuel injector, typically one of several, supplied by way of a high-pressure fuel line with highly pressurized fuel for the injection of the fuel into the combustion space of the internal-combustion engine during an injection operation. A pressure control valve connected in front of the fuel injector in the high-pressure fuel line is provided for controlling the pressure of the fuel injected during the injection operation. The pressure control valve contains a freely displaceable piston operating on both sides and a slide connected into the flow path of the high-pressure fuel line for the opening and closing of the passage cross-section of the flow path of the high-pressure fuel line as a function of the position of the piston.

Abstract: A pressurized-fluid-operated actuator has multiple piston surfaces for providing increased output force. The actuator includes a stationary cylinder that contains a movable cylinder having multiple inner chambers separated by stationary inner pistons. The inner chambers are in fluid communication with extension and retraction ports provided in the stationary cylinder wall. Introduction of pressurized fluid into one port causes the fluid pressure to act on “n” piston surface(s) to retract the movable cylinder. Introduction of pressurized fluid into the other port causes the fluid pressure to act on “n+1” piston surfaces to provide an increased output force without increasing the diameters of the cylinders and without increasing the pressure of the fluid.

Abstract: The circuit comprises first and second power lines connected to a port of a first actuator chamber and to the port of a second actuator chamber, respectively; a supply line and a discharge line connected to a supply source and to a discharge reservoir; a first sliding member valve capable of connecting the first power line to the supply and discharge lines under the control of pilot pressures transmitted to the first sliding member valve by a first pair of pilot lines; and a second sliding member valve capable of connecting the second power line with the supply and discharge lines under the control of pilot pressures transmitted to the second sliding member valve by a second pair of pilot lines.