Abstract: A valve in which the flow control element includes a fixed disk and a rotatable disk, and a motor operable to rotate the rotatable disk. The motor is disposed in the bore of the valve, aligned with the long axis of the valve body and the axis of rotation of the rotatable disk.

Abstract: A shutoff vent is disclosed. A main body has a first end and a second end. The main body defines a first opening towards the first end, a second opening towards the second end, and a mating port between the first opening and the second opening. The first opening and the second opening are in communication through the mating port to define a gas passageway. A translatable plug is disposed within the main body, and the gas passageway extends past the translatable plug. The translatable plug is configured to reversibly translate towards the second end to sealably obstruct the mating port. In some examples, the translatable plug is configured to translate towards the second end when force is applied to the translatable plug from the first end.

Abstract: A compressed gas gun including a housing and a bolt movable within a passage in the housing. Movement of the bolt relative to the housing opens a flow path for firing a projectile.

Abstract: An actuatable flow media for the control of a flow rate of a liquid through the flow media, the actuatable flow media comprising a base having at least one cavity formed therein, at least one aperture formed in the cavity defining a liquid flow path for the entry of liquid into or exit of liquid from the flow media; a flexible membrane arranged in spaced relation with the base and defining a liquid flow path through the flow media; and an elastically deformable element arranged in the cavity and extending between the base and the flexible membrane for actuation between at least a first configuration in which the element is substantially undeformed and the liquid flow path through the at least one aperture is open and a second configuration in which the element is substantially deformed and the liquid flow path through the at least one aperture is closed.

Abstract: In one aspect, a pressure sensor for detecting a pressure differential between first and second fluid sources may include sensor body defining a cavity and a seal plate slidably positioned within the cavity. The seal plate may define first and second chambers within the cavity, which may respectively be in fluid communication with the first and second fluid sources. The sensor may also include a sensing element configured to detect a position of the seal plate relative to the sensor body, which may be indicative of the pressure differential between the first and second fluid sources. The sensor may further include a first spring positioned within the first chamber and compressed between a first side of the seal plate and the sensing element. Additionally, the sensor may include a second spring positioned within the second chamber and compressed between a second side of the seal plate and the sensor body.

Abstract: A compressed gas gun including a housing and a bolt movable within a passage in the housing. Movement of the bolt relative to the housing opens a flow path for firing a projectile.

Abstract: A solenoid valve driving apparatus includes switching means for ON/OFF-controlling application of a direct current voltage to a solenoid of a solenoid valve, and signal outputting means. A first period and a consecutive second period are set as a valve opening operation period of the solenoid valve. When the signal outputting means outputs the PWM signal to the switching means, a duty ratio of the output signal is set to be higher in the second period than in the first period so that a power supplied to the solenoid is larger in the second period than in the first period. As a result, a valve opening operation is performed in the solenoid valve reliably, and loud noise generation during the valve opening operation is suppressed.

Abstract: According to an embodiment of the disclosure, a system for regulating a pressure differential includes a plurality of valving elements and a valve activation system. Each of the plurality of valving elements are configured to selectively allow and restrict at least a portion of a flow of fluid between an inlet and an outlet of a conduit through a respective opening and closing of each respective valving element. The valve activation system is configured to supply a common driving pressure to the plurality of valving elements. The common driving pressure is configured to initiate at least one of the opening or closing of the plurality of valving elements or to initiate the other of the opening or closing of the plurality of valving elements.

Abstract: A system for manually overriding a solenoid operated valve in an event of power failure is provided. The system includes a solenoid operated valve and a lifter. The solenoid operated valve includes a valve body including a sealing surface, a fluid inlet and a fluid outlet, a sealing element selectively separating the fluid inlet from the fluid outlet and a solenoid configured to selectively couple and decouple the sealing element to the sealing surface. The lifter is threadedly coupled to the solenoid operated valve. Rotation of the lifter relative to the valve body in a first direction causes the lifter to decouple the sealing element from the sealing surface.

Abstract: A backflow and flow rate control system, comprising: a flow restrictor; a flow regulator chamber located down-stream of the flow restrictor; a control chamber configured to receive a portion of the fluid from a location upstream of the flow restrictor; a moveable element with no sliding parts positioned between the control chamber and the flow regulator chamber, wherein the moveable element is configured to move in response to a difference in pressure between the flow regulator chamber and the control chamber; a flow rate regulator configured to control the flow rate of the fluid in response to the movement of the moveable element; and a non-return regulator coupled with the moveable element and configured to control back-flow of the fluid.

Abstract: Fail-safe apparatus for use with fluid valves are disclosed herein. An example fail-safe apparatus includes a first piston, a second piston movably coupled relative to the first piston, and a fluid chamber between the first and second pistons to receive a control fluid. The control fluid is to operatively couple the first and second pistons when the control fluid is provided in the fluid chamber. The first piston is operatively decoupled from the second piston when at least some of the control fluid is removed from the fluid chamber.

Abstract: An adjustable damping valve arrangement for a vibration damper includes a main stage valve with a main stage valve body which is guided in a damping valve housing so as to be axially movable. 6 The damping valve housing has a housing insert which is separate from the damping valve housing and in which the main stage valve body is guided.

Abstract: A hydraulic pilot control arrangement for a spool valve is provided, wherein the spool of the spool valve is biased towards a central position. The arrangement includes a first and a second pilot hydraulic line connected to opposite sides of the spool of the spool valve and a pilot pressure regulating arrangement is provided for selectively establishing or removing a pilot pressure in each of the first and second lines. The arrangement includes a damping device including a chamber divided into a first and a second pressure compartment by a sliding piston, the first and second pressure compartments being connected respectively to the first and second pilot hydraulic lines, and the piston is biased towards a rest position in the chamber.

Abstract: An activation element of an electromagnetic actuating unit of a hydraulic valve which has an armature that is essentially cylindrical and which is arranged in a slidable fashion in the actuating unit. Also, a method for manufacturing an activation element of an electromagnetic actuating unit of a hydraulic valve. The activation element has at least one substantially cylindrical armature, one plunger rod and one magnet cone. The plunger rod and the magnet cone are embodied in one piece with the armature.

Abstract: A solenoid valve for controlling a fluid includes an armature having a base region, a lateral region and a head region. The solenoid valve includes a valve member connected to the armature. The solenoid valve further includes an armature casing component in which the armature is positioned. A flow path is formed between the armature and the armature casing component, the flow path extending from a lower armature space to an upper armature space and back to the lower armature space. A junction region is arranged between the head region and the lateral region. The junction region has at least one groove formed therein to facilitate an overflow between the lateral region and the head region.

Abstract: Solenoid operated fluid control valve for controlling the pressure of a fluid in a fluid control system comprises a solenoid housing having therein a solenoid coil, an armature movable in response to electrical current applied to the solenoid coil, a valve member for controlling fluid flow to a fluid passage, an actuator pin disposed between the armature and the valve member for moving the valve member in response to armature movement, and one or more features including an armature damping member, tubular actuator pin support body, flow diverter, coil bobbin support sleeve, and/or internal particle gettering magnet to improve valve operation.

Abstract: A push type water tap with automatic closing functions wherein a through valve tube and a protruding bottom tube are set separately into the chambers of the main body. A lifting valve lever is assembled into the valve tube and bottom tube. A stop ring can be abutted onto the water stop ring flange for stopping water supply. A restoring spring is set between the top of the valve lever and the lock-joining seat, and supports the valve lever and the push button. A single-way check ring is sleeved on the bottom of the valve lever to keep contact with the wall of the bottom tube. A resettable regulating space is formed by the gap between the bottom of the valve lever and the sealing surface. A resettable regulating water channel is set on the bottom of the valve lever to guide water into the regulating space.

Abstract: A fuel injector has a housing with a central longitudinal axis having a first cavity and may be coupled to a fuel rail having a fluid inlet portion and outlet portion. The fuel injector has a valve needle arranged at least partly within the housing axially movable in the first cavity facing the fluid outlet portion, the valve needle preventing a fluid flow through the fluid outlet portion in a closing position and releasing it through the fluid outlet portion in further positions. The fuel injector has a spring arranged within the first cavity for exerting a spring force on the valve needle along the central longitudinal axis for preventing the fluid flow through the fluid outlet portion. Additionally, the fuel injector has an adjusting element for adjusting an axial position regarding the central longitudinal axis of a spring rest depending on a pressure acting on the adjusting element.

Abstract: A faucet includes a body with a first fluid inlet, a second fluid inlet, an outlet and a neck portion with a central cavity defined therein, a mixing chamber positioned within the central cavity of the neck portion of the body, a timing mechanism coupled to the mixing chamber and an operating handle coupled to the timing mechanism that is movable along a longitudinal axis from a closed position to an open position. The mixing chamber is rotatable about the longitudinal axis and includes a first inlet port and a second inlet port in fluid communication with the first and second fluid inlets of the body, respectively, and an outlet port in fluid communication with the outlet of the body.

Abstract: A cartridge including an anti-ram device comprises a multiple braking mechanism, including at least two pistons housed in the cover/driver element of a top movable plate, on the sides of a milled ball seat of the faucet control rod.

Abstract: Pressure regulator device comprising a body (1), a minimum of a pressure reducer and a damper mounted in control and damping cavities, respectively, in the body (1), and a control member (4) pivoting on an upper face (10) of the body (1). The device is noteworthy in that the control and damping cavities have open ends in a peripheral face (12) of the body (1) and the control member (4) has parts (47) that are opposite the peripheral face (12) in order to face the open ends of the respective control and damping cavities, from which control (21) and damping pushrods, respectively, project. The present invention has an application in the hydraulic remote controls of civil engineering machines.

Abstract: A controllable solenoid valve having a sealed chamber that isolates the armature cavity from the function fluid or external water sources with oil or dielectric fluid and is ported to a reservoir or to a surrounding housing to maintain fluid communication with the armature cavity. The valve may also have a closed internal chamber filled with oil or dielectric fluid to maintain isolation of the armature cavity from the function fluid or other water sources. The closed chamber may also encompass the electrodes or the coil of the solenoid. In a preferred embodiment, the chamber is in fluid communication with transducers that sense fluid pressure.

Abstract: An apparatus for controlling flow of a fluid includes a closure member, a biasing member applying a biasing force to the closure member, and a sealing member receiving the closure member. A dampener is operatively connected to the closure member and may resist a force applied to the closure member. A fluid seal may be formed when the biasing member presses the closure member against the sealing member. The apparatus may include a wellbore tubular in which the fluid conduit is formed and the closure member and sealing member may cooperate to control fluid flow along the fluid conduit. The apparatus may include an actuator configured to control the force applied to the closure member. The actuator may adjust the biasing force, and/or the dampening force. Also, a controller may control the actuator and may be responsive to a signal generated at a surface location, a signal generated at a downhole location, and/or a signal generated by a sensor.

Abstract: An adjustable damping valve including an actuator, which exerts an actuating force on a valve body against the force of a spring to influence the throttle cross section which determines the damping force, where an emergency valve is connected in parallel with the throttle cross section with respect to the flow direction of the damping medium, where the two control surfaces of the valve body move in the axial direction and can thus can come to rest alternately on the two valve seating surfaces, and where the valve body is divided into two parts in the longitudinal direction, and each valve body assembly has its own control surface.

Abstract: A metering device has an actuating unit within a housing in which an actuator is inserted and a hydraulic compensating element. The hydraulic compensating element is connected to the actuator and can be filled with a fluid when subjected to pressure. A first end of the actuator is provided with a first end cap. The metering device further has a stop that is disposed on the housing in the form of a seat, faces the first end cap, and defines a stopping position for the first end cap. The stop maintains a maximum distance between a sealing element and the end cap, the distance being smaller than the actuator traveling distance such that the actuator stroke beyond the end cap is sufficient for opening the valve. The first end cap hits the stop when moving in the direction of the hydraulic compensating element such that the movement is blocked.

Abstract: A reset relief valve with a body having an inlet port, an outlet port, and an interior wall partially defining an enclosed chamber, a piston disposed in the body and moveable between a first position at which the piston is disposed in fluid flow-blocking relationship between the inlet port and the outlet port of the body and a second position at which the piston is removed from that position, a piston having a head with opposed end surfaces one of which defines a portion of the enclosed chamber and at least one fluid flow passageway extending through the head and providing fluid communication between the enclosed chamber in the body, and a second chamber above a moveable disc in the piston and a pressure sensor in fluid communication with the fluid in the chambers. A preferred embodiment includes data acquisition software for monitoring data and storing pressure and other data to control the operation of the valve.

Abstract: The invention provides a solenoid actuated valve with a plunger which moves in a sleeve under influence of a magnetic field from the solenoid and further comprising a damping device for reducing noise and wear caused by the plunger when it bounces against a top part located in the sleeve. The damping device comprises a first part which forms the limit of the travel of the plunger and another part which is allowed to move relative to the first part in a dampened movement. To enable application in a vacuum system, the damping device comprises a conduit which allows evacuation of a chamber confined between one end of the sleeve and the damping device. The invention further provides a damper for a solenoid actuated valve.

Abstract: An improved sequencing fluid control valve comprising a housing having inlet and outlet ports, a valve seat disposed within the housing, a collapsible valve member disposed within the housing and forming a chamber and a bulb. A sequencing means disposed within the chamber that controls the axial motion of the valve member in response to application of fluid pressure at the inlet such that the motion of valve member alternates between an open free flowing state and a closed restricted flow state. Housing and valve member cooperate in the open position to provide an annular flow path that does not require the fluid flow direction to substantially change while flowing from inlet to outlet. Housing and valve member bulb cooperate in the closed position to form a circumferential seal to restrict the fluid flow. Alternative embodiments including viscous damping means and variations on the housing mount are described.

Abstract: A device that relieves lubricant pressure in a divider block lubrication system into a fluid reservoir, a container, or directly back into the compressor frame to which the tubing is connected. This eliminates housekeeping, environmental, safety, and compressor component failure concerns associated with current atmospheric rupture assemblies that relieve directly to the atmosphere. The environmental compressor protection assembly contains a spring set to a pre-determined pressure. Lubricant pressure in excess of this pre-determined set pressure results in spring compression and opening of a relief path. The assembly preferably remains in a full open position and must be must be manually reset to the closed position to prevent fluid flow in the system.

Abstract: A water faucet includes a receptacle engaged into a housing and having a passage communicating with a water outlet of the housing, a valve stem slidably engaged through the passage of the receptacle and having a valve member for controlling the water to flow from the water inlet to the water outlet of the housing, and a piston attached to the valve stem and slidably engaged in a compartment of the receptacle, the valve stem includes one or more orifices and one or more apertures for controlling a fluid to flow between the compartment of the receptacle and a cavity of the valve stem, and a valve element may adjust the flowing of the fluid into and out of the cavity of the valve stem.

Abstract: The invention provides a solenoid actuated valve with a plunger which moves in a sleeve under influence of a magnetic field from the solenoid and further comprising a damping device for reducing noise and wear caused by the plunger when it bounces against a top part located in the sleeve. The damping device comprises a first part which forms the limit of the travel of the plunger and another part which is allowed to move relative to the first part in a dampened movement. To enable application in a vacuum system, the damping device comprises a conduit which allows evacuation of a chamber confined between one end of the sleeve and the damping device. The invention further provides a damper for a solenoid actuated valve.

Abstract: A poppet valve device includes a plurality of axial passages of substantially the same diameter and length communicating with a high-pressure room formed inside a valve seat member between a poppet valve body and the valve seat member. The passages are located adjacent to each other and an annular gap formed between the periphery of the poppet valve body and an inner perimeter of a projecting part on which a valve seat face of the valve seat member is formed, is narrow to restrict liquid flow through the annular gap. An electronic controlled fuel injection apparatus equipped with the poppet valve device is composed such that a lower end part of the poppet valve body and a bottom of a valve device accommodating part of the fuel injection apparatus are formed to restrict flow of fuel to prevent the occurrence of bouncing.

Abstract: A fuel injection valve comprises: a solenoid unit including a core, an armature and a coil; and a valve unit including a valve element connected to the armature to travel therewith, and a valve seat that regulates a movement in valve closing direction of the valve element, and is open and closed by the valve element separating from or coming in contact with the valve seat, and a stopper for regulating a movement in valve opening direction of the valve element, said valve unit being connected to the solenoid unit. There is provided a cavity that communicates with a gap formed between the core and the armature in opposition, and the cavity forms a resonator for suppressing bounce of the valve element. In spite of the simple structure, it is possible to effectively suppress bounce of the valve element that takes place at the time of valve opening/closing.

Abstract: The present invention is directed for use in a valve assembly including a housing having an axis and defining an interior, with fluid provided in the housing and substantially filling the housing interior, a valve stem disposed in the housing interior and a piston attached to the valve stem, wherein the piston and valve stem are moveable along the housing axis within the housing interior between first and second positions. The present invention includes a valve actuation control device disposed in the housing interior, the valve actuation control device allowing the fluid to freely flow from one side of the piston to the other side during at least a portion of the piston's movement between the first and second positions.

Abstract: A poppet valve device includes a plurality of axial passages of substantially the same diameter and length communicating with a high-pressure room formed inside a valve seat member between a poppet valve body and the valve seat member. The passages are located adjacent to each other and an annular gap formed between the periphery of the poppet valve body and an inner perimeter of a projecting part on which a valve seat face of the valve seat member is formed, is narrow to restrict liquid flow through the annular gap. An electronic controlled fuel injection apparatus equipped with the poppet valve device is composed such that a lower end part of the poppet valve body and a bottom of a valve device accommodating part of the fuel injection apparatus are formed to restrict flow of fuel to prevent the occurrence of bouncing.

Abstract: A pilot-type two-port valve is disclosed having a water hammer preventing mechanism, operative to prevent a water hammer during valve-closing operation, which includes a valve member operative to open or close a valve and a piston driven by pilot fluid for operating the valve member for opening and closing movements. The water hammer preventing mechanism comprises a piston drive chamber, from which fluid is discharged during valve-closing operation, which has an orifice for restricting the flow rate of discharge fluid whereby when the piston moves to a position to allow the valve member to be close to a valve seat, a portion of an discharge flow passage of the piston drive chamber is blocked to restrict the flow rate of the discharge fluid to the flow rate of fluid flowing through the orifice.

Abstract: A reset relief valve with a body having an inlet port, an outlet port, and an interior wall partially defining an enclosed chamber, a piston disposed in the body and moveable between a first position at which the piston is disposed in fluid flow-blocking relationship between the inlet port and the outlet port of the body and a second position at which the piston is removed from that position, a piston having a head with opposed end surfaces one of which defines a portion of the enclosed chamber and at least one fluid flow passageway extending through the head and providing fluid communication between the enclosed chamber in the body, and a second chamber above a moveable disc in the piston and a pressure sensor in fluid communication with the fluid in the chambers. A preferred embodiment includes data acquisition software for monitoring data and storing pressure and other data to control the operation of the valve.

Abstract: The ceramic valve structure has a slow-descending device between the valve stick and the valve shaft base. The slow-descending device mentioned herein includes a piston, a piston slot and sealer, and the piston slot is placed on one side of the valve shaft base. A venthole is placed at the bottom of the piston slot, and the bottom of the piston is placed inside the piston slot. The joint of the top of the piston slot is connected to the swing end. The sealer is placed on top of the venthole of the piston. When the valve stick of the ceramic valve is being turned off, it creates a resistance by the slow-descending device, which slows the process of water being tuned off, in turn, slowing down the change in water pressure, reducing damage to the water channel and ceramic valve, and extending a shelf life of the ceramic valve structure.

Abstract: A reset relief valve with a body having an inlet port, an outlet port, and an interior wall partially defining an enclosed chamber, a piston disposed in the body and moveable between a first position at which the piston is disposed in fluid flow-blocking relationship between the inlet port and the outlet port of the body and a second position at which the piston is removed from that position, a piston having a head with opposed end surfaces one of which defines a portion of the enclosed chamber and at least one fluid flow passageway extending through the head and providing fluid communication between the enclosed chamber in the body, and a second chamber above a moveable disc in the piston. A preferred embodiment includes the crank assembly with cross bar support and a T-bar to prevent downward movement of the disc.

Abstract: The ceramic valve structure has a slow-descending device between the valve stick and the valve shaft base. The slow-descending device mentioned herein includes a piston, a piston slot and sealer, and the piston slot is placed on one side of the valve shaft base. A venthole is placed at the bottom of the piston slot, and the bottom of the piston is placed inside the piston slot. The joint of the top of the piston slot is connected to the swing end. The sealer is placed on top of the venthole of the piston. When the valve stick of the ceramic valve is being turned off, it creates a resistance by the slow-descending device, which slows the process of water being tuned off, in turn, slowing down the change in water pressure, reducing damage to the water channel and ceramic valve, and extending a shelf life of the ceramic valve structure.

Abstract: A controllable solenoid valve having a sealed chamber that isolates the armature cavity from the function fluid or external water sources with oil or dielectric fluid and is ported to a reservoir or to a surrounding housing to maintain fluid communication with the armature cavity. The valve may also have a closed internal chamber filled with oil or dielectric fluid to maintain isolation of the armature cavity from the function fluid or other water sources. The closed chamber may also encompass the electrodes or the coil of the solenoid. In a preferred embodiment, the chamber is in fluid communication with transducers that sense fluid pressure.

Abstract: An electric motor actuated stop/check valve for industrial use such as liquid pumping systems which has a controlled opening and closing rate when liquid flow is in a forward direction but closes quickly upon reverse flow of liquid with no action from the electric motor actuator.

Abstract: Hydraulic actuator as an element of a system for controlling an engine valve is presented. The actuator includes a fluidic actuation chamber, defined by an actuation piston that increases chamber volume as the actuation piston is urged away from a neutral. Chamber includes a high pressure fluid inlet and a fluid outlet. A fluidic actuator control chamber, defined by a control piston connected to the actuation piston that increases chamber volume as the actuation piston is urged away from neutral. A control fluid outlet is connected to a fluid control spool valve. The fluid outlet of the actuation chamber is fluidly connected to an inlet of the control valve. There is a valve actuation plunger operably connected to the actuation piston, and a drain outlet to maintain a fluidic backpressure to the actuator control chamber.

Abstract: A reset relief valve with a body having an inlet port, an outlet port, and an interior wall partially defining an enclosed chamber, a piston disposed in the body and moveable between a first position at which the piston is disposed in fluid flow-blocking relationship between the inlet port and the outlet port of the body and a second position at which the piston is removed from that position, a piston having a head with opposed end surfaces one of which defines a portion of the enclosed chamber and at least one fluid flow passageway extending through the head and providing fluid communication between the enclosed chamber in the body, and a second chamber above a moveable disc in the piston. A preferred embodiment includes the crank assembly with cross bar support and a T-bar to prevent downward movement of the disc.

Abstract: A device, for the translation of a displacement of an actuator, in particular for an injection valve, essentially comprises two counter-displaceable pistons, coupled together by means of a translational chamber in a play-free manner. The translation chamber is filled with a translation medium and is connected to an equalization chamber by means of a sealing gap. The sealing gap only equalizes pressure differences between the translation chamber and the equalization chamber which are of long duration. One of the two pistons is pre-tensioned in a starting position by means of an externally arranged spring. A reduction in the dead volume between the pistons is possible as a result of the arrangement of the spring outside the piston.

Abstract: A fuel injector for fuel-injection systems of internal combustion engines having a piezoelectric or magnetostrictive actuator, includes a hydraulic coupler which actuates a valve-closure member (3) formed on a valve needle. The valve-closure member cooperates with a valve-seat surface to form a valve-sealing seat. The coupler includes a master piston and a slave piston which are guided in bores of a guide sleeve. Located between the master piston and the slave piston is a pressure chamber filled with a hydraulic fluid. A corrugated tube is positioned around the guide sleeve which is sealingly joined to the master piston at one end and to the slave piston at the other end, and which seals a supply chamber for the hydraulic fluid from a surrounding fuel chamber.

Abstract: When a plunger moves toward a side of a valve seat, an end face of a sealing member on a space side is separated from a surface of a seal housing groove, whereby a portion between a communication passage formed on an inner peripheral side of the sealing member is communicated with the space. At this time, an end face of the sealing member on a side of a damper chamber contacts the surface of the seal housing groove. However, since a part of a communication groove is communicated with the communication passage, the damper chamber is communicated with the communication passage through the communication groove. Accordingly, since the damper chamber is communicated with the space through the communication passage, a damping effect is not exerted.

Abstract: For use in a valve assembly including a housing having an axis and defining an interior, with fluid provided in the housing and substantially filling the housing interior, a valve stem disposed in the housing interior and a piston attached to the valve stem, wherein the piston and valve stem are moveable along the housing axis within the housing interior between first and second positions, a valve actuation control device is provided which is disposed in the housing interior, the valve actuation control device allowing the fluid to freely flow from one side of the piston to the other side during only a first portion of the piston's movement between the first and second positions.

Abstract: A pressure relief valve has a housing fluidly connected to a pressurized system line carrying a system fluid. The housing carries a moveable piston and a valve member that both move between closed and open positions. The piston defines an upper chamber and a lower chamber within the housing. A pressurized fluid is supplied to the upper chamber to bias the piston toward the closed position. After the relief valve opens from excessive system pressure, the pressurized fluid is injected into the lower chamber to delay the return of the piston to the closed position. Initially, the fluid in the lower chamber flows through a check valve while the piston returns to the closed position. Then the fluid vent in the lower chamber vents from the lower chamber as the piston and valve member approach the closed position.

Abstract: A retracting telescoping automatic fire sprinkler is disclosed. In a dry system, the sprinkler extends to its operating position under system pressure that is applied in response to a preaction signal. When system pressure is removed, as in after a test is completed, the sprinkler automatically retracts to its original position.