Abstract: A pulsation attenuator for a fluidic system with a fluidic pump. The pulsation attenuator includes a fluidic channel, a first fluidic device adapted to attenuate pulsations with a shallow rolloff slope, and a second fluidic device adapted to attenuate pulsations with a shallow rolloff slope. The first fluidic device and the second fluidic device are connected to the fluidic channel such that they cooperatively attenuate pulsations with a steep rolloff slope. Preferably, the first fluidic device includes a first fluidic resistor and a first fluidic capacitor, and the second fluidic device includes a second fluidic resistor and a second fluidic capacitor. Preferably, the pulsation attenuator is arranged, similar a second-order low-pass filter, in the following order: (1) first fluidic resistor, (2) first fluidic capacitor, (3) second fluidic resistor, and (4) second fluidic capacitor.

Abstract: A piston-type accumulator includes a separating piston (24) axially displaced inside an accumulator housing (10) and separating two spaces from one another inside the accumulator housing (10), particularly a gas side (22) from a liquid side (20) of the accumulator. Due to the fact that the separating piston (24) is predominantly or completely made of a plastic material, it can be provided with a very light weight reducing the overall installation weight of the piston-type accumulator.

Abstract: An accumulator for a hydraulic system, wherein the accumulator comprises a liner, a piston and a housing, that defines a pressure chamber, for receiving hydraulic fluid at high pressure, wherein the piston is biased towards an end position of the pressure chamber for interacting with the hydraulic fluid in the pressure chamber, and the piston is movable in a predetermined range for accumulating hydraulic fluid. The accumulator has at least one outlet port in a sidewall of the liner, which outlet port is covered by the piston in the predetermined range and is uncovered when the piston has moved a predetermined distance from the end position. A hydraulic system is also provided that comprises the above accumulator and an all-wheel drive system comprising the above hydraulic system. A method for de-airing an accumulator according to above is also provided.

Abstract: A hydraulic breaker hammer comprises a housing (10) with a longitudinal bore (12), a cylinder sleeve (14), and a cylinder sleeve (14) engaging rear end cover (16), a hammer piston (15) reciprocally powered in the cylinder sleeve (14) for delivering blows to a working implement inserted in a guide sleeve (20) at the front end of the bore (12), wherein the guide sleeve (20) is provided with radial openings (22a,b) for communication of lubricant from a lubricant supply passage (21) in the housing (10) to the inside of the guide sleeve (20), and the guide sleeve (20) is provided with external seal rings (23 a-d) forming annular compartments located between the lubricant supply passage (21) and the radial openings (22 a,b) for spreading lubricant on the outside surface of the guide sleeve (20), a distribution valve (31) communicating with the pressure fluid source and the cylinder sleeve (14) and comprising both a clearance seal means (44) and a seat seal (45,46) for improved tightness, and a pressure accumulator

Abstract: A piston-in-sleeve accumulator includes a cleaning element positioned on the piston and configured to remove and prevent debris from lodging between the piston and a cylindrical nonpermeable sleeve within which the piston slides. A seal on the piston is positioned to engage an opposing surface in the event of a leak, and thereby prevent the possibility of a complete drainage of pressurized fluid from occurring through the accumulator's fluid port. A position contactor switch is further provided to signal position of the piston within the accumulator.

Abstract: A lightweight, optimally efficient, easily serviced, piston-in-sleeve high pressure accumulator is provided. The accumulator includes one or more cylindrical composite pressure vessel separate end cap manifolds. A piston slidably disposed in a thin impermeable internal sleeve in the accumulator separates two chambers, one adapted for containing a working fluid and the other adapted for containing gas under pressure. Gas is provided in a volume between the impermeable internal sleeve and the composite pressure vessel wall. Additional gas is optionally provided in gas cylinders. Further components are provided for withstanding harmful effects of radial flexing of the composite vessel wall under high pressures, and from stresses present in use in mobile applications such as with a hydraulic power system for a hydraulic hybrid motor vehicle.

Abstract: A subsea equipment (1) used for natural gas or crude oil production, such as a subsea actuator (2) for a valve, a restrictor or the like, a control module or other means, comprises at least an oil-filled first component (3) and a compensator unit (4) which is associated with said first component and which is in fluid communication therewith for pressure compensation. To improve such a subsea equipment in a structurally simple manner in such a way that it is capable of functioning and that pressure compensation is still possible, even if the associated compensator unit is damaged or fails to operate, a second compensator unit (5) is in fluid communication with said first component (3) or said first compensator unit (4) for pressure compensation.

Abstract: The invention relates to a piston-type accumulator comprising a separating piston (24), which can be axially displaced inside an accumulator housing (10) and which separates two spaces from one another inside the accumulator housing (10), particularly a gas side (22) from a liquid side (20) of the accumulator. Due to the fact that the separating piston (24) is predominantly or completely made of a plastic material, it can be provided with a very light weight whereby reducing the overall installation weight of the piston-type accumulator.

Abstract: A piston-type accumulator includes an accumulator housing provided in the form of a cylinder tube (1). A separating piston (15) separates two working spaces (5) and (6) from one another in the housing and can be displaced in an axial direction within a piston stroke area (19) of the cylinder tube (1). The cylindrical tube is closed at one axial end by a closure part (7). The closure part is defined by deforming a deforming area (9) of the wall of the cylinder tube (1). The deforming area adjoining the piston stroke area (19) is provided in the form of part that exists as a single piece with the housing. A stop body (25), which limits the movement of the separating piston (15) before reaching the deforming area (9), is provided inside the cylinder tube (1) at the location where the piston stroke area (19) transitions into the deforming area (9).

Abstract: A vehicular brake system component is used in a brake system of a vehicle. The brake system component includes a sealable bonded component having a metal member and an elastic rubber member bonded to each other and located so as to touch a brake fluid.

Abstract: An accumulator comprises a housing connected to a hydraulic system, an elastomeric bladder separating a gas compartment from a fluid compartment, and an anti-extrusion device. A method for operating an accumulator comprises connecting the accumulator to a hydraulic system, injecting an inert gas into a gas compartment to a precharge pressure, moving an anti-extrusion device to prevent a bladder from extruding into the hydraulic system, running the accumulator and the hydraulic system downhole, moving the anti-extrusion device to allow fluid communication between the hydraulic system and a fluid compartment, generating pressure fluctuations within the hydraulic system, and expanding or contracting the bladder in response to the pressure fluctuations without moving the anti-extrusion device.

Abstract: A pulsation attenuator for a fluidic system with a fluidic pump. The pulsation attenuator includes a fluidic channel, a first fluidic device adapted to attenuate pulsations with a shallow rolloff slope, and a second fluidic device adapted to attenuate pulsations with a shallow rolloff slope. The first fluidic device and the second fluidic device are connected to the fluidic channel such that they cooperatively attenuate pulsations with a steep rolloff slope. Preferably, the first fluidic device includes a first fluidic resistor and a first fluidic capacitor, and the second fluidic device includes a second fluidic resistor and a second fluidic capacitor. Preferably, the pulsation attenuator is arranged, similar a second-order low-pass filter, in the following order: (1) first fluidic resistor, (2) first fluidic capacitor, (3) second fluidic resistor, and (4) second fluidic capacitor.

Abstract: A pressure container has a steel pipe and an end plate that is formed with a joint portion by allowing its tapered surface to touch a tapered surface of an opening end of the steel pipe so as to block the opening end. The steel pipe has a flange portion which can be cut at the opening end of the steel pipe, and the joint portion is allowed to touch the flange portion. The flange portion is pressed against the opening end along an axial direction so as to touch the end plate, and while the end plate is being pressed against the steel pipe along the axial direction, an electric current is applied so that welding is carried out.

Abstract: A hydraulic accumulator includes a piston (3) capable of moving in an accumulator housing (1) in its axial direction and separating a gas side (5) from a liquid side (7) of the accumulator housing (1). Guide elements (9, 17) designed to co-operate with the accumulator housing wall (1), as well as at least one sealing element (15), are arranged at the periphery of the piston. The sealing element is arranged offset in the axial direction relative to the guide elements (9, 17), and is located between the guide elements. In the piston (3), a pressure compensating channel (19) forms, at the piston periphery, a liquid flow path between the liquid side (7) and a space (2) located between the guide element (17) nearest to the liquid side (7) and the sealing element immediately next in the axial direction. A device (25) reducing the cross-section of the passage of the pressure compensating channel (19) is located in it.

Abstract: A device for damping pressure surges in a fluid with a housing (10) and a piston (14) that can be longitudinally displaced inside the housing (10) against the pretensioning force of a spring energy store (12). The piston (14) interacts with another piston (24), which is guided in a connecting piece (26) of the housing (10) in a manner that enables it to be longitudinally displaced. During the operation of the device, the piston (14) exerts a pressure force onto the other piston (24) when the other piston is in any displacement position. Even pressure surges occurring with a high frequency can be reliably controlled in a functionally reliable manner.

Abstract: An accumulator comprises a housing connected to a hydraulic system, an elastomeric bladder separating a gas compartment from a fluid compartment, and an anti-extrusion device. A method for operating an accumulator comprises connecting the accumulator to a hydraulic system, injecting an inert gas into a gas compartment to a precharge pressure, moving an anti-extrusion device to prevent a bladder from extruding into the hydraulic system, running the accumulator and the hydraulic system downhole, moving the anti-extrusion device to allow fluid communication between the hydraulic system and a fluid compartment, generating pressure fluctuations within the hydraulic system, and expanding or contracting the bladder in response to the pressure fluctuations without moving the anti-extrusion device.

Abstract: The present invention relates to an arrangement in an energy-accumulating piston-cylinder device (1, 2) having a piston (2) and a cylindrical casing (1). The invention is characterized by an openable safety valve (1) arranged in the piston (2) and/or a discharge duct (11) together with an element (8; 17) arranged on the cylindrical casing (1) or the safety valve (10) and in the cylinder chamber, which element is designed, in the event of the piston (2) being inserted into the cylinder chamber by more than a predetermined distance, to act upon the safety valve/the discharge duct (10, 11) in order to expose the said duct (11), permitting a discharge of the pressure in the cylinder chamber.

Abstract: A hydraulic accumulator includes an accumulator housing (1) formed of a non-magnetizable material and defining an axial direction of the housing. A separating element (9) can be axially displaced in the accumulator housing (1) and separates two working chambers (5, 7) from each other in the accumulator housing (1). A field-generating magnetic configuration (29) is arranged on the separating element. A series of magnetic field sensors (35) are arranged on the outer side of the accumulator housing (1), extend along the path of the axial movement of the separating element (9) and react to the field of the magnetic configuration (29) on the separating element (9) to characterize its position along the series of magnetic field sensors (35).

Abstract: A device damps water hammers in hydraulic accumulators, in particular in piston accumulators. The device is embodied in the form of the accumulator component which operates as a throttle on a fluid flow and is inserted between internal elements (12) of the accumulator and a hydraulic network (14) to which the accumulator is connectable. The throttle is formed by at least one transfer area (24) having a predetermined cross-section in a valve element (16) which interrupts the fluid flow up to the transfer area (24) at one of the valve positions and releases it at its other position. The transfer area (24) has at least one free end with a funnel-shaped enlargement (26,28) oriented towards the inside of the accumulator (12) or towards the hydraulic network (14), thereby substantially improving damping such that noise emission is reduced to the greatest possible extent.

Abstract: A gas valve assembly for a shock absorber includes a first portion of a first material and a second portion of second material which is less rigid than the first material. The first portion defines a rigid valve assembly body having a threaded portion to mount the valve to the shock body. The second portion is resilient and defines an integral plug and annular seal interconnected by a connecting member. The annular seal is molded adjacent a step engagement surface to seal the gas valve assembly to the shock body. A head having a tool engagement surface compresses the annular seal when the gas valve assembly is threaded in place.

Abstract: The invention relates to a fluid power accumulator in which the fluid undergoes a state change as the system is pressurized to store energy. A state change can be a phase change, a chemical reaction, or a combination of these. Generally the state change results from the interaction of a compressible fluid contained in the accumulator with another substance, which can be a fluid or a solid. Preferably, the state change includes the physical adsorption of a fluid by a solid adsorbant. The invention can improve the energy storage density of a fluid power accumulator, allow a given energy storage density to be achieved at a lower maximum pressure, facilitate heat transfer and storage within an accumulator, and/or improve accumulator efficiency by storing energy in a form other than thermal energy, such as in the form of chemical energy.

Abstract: A lightweight, low permeation, piston-in-sleeve high pressure accumulator is provided. The accumulator includes a cylindrical composite pressure vessel with two integral rounded ends. A piston slidably disposed in a thin nonpermeable internal sleeve in the accumulator separates two chambers, one adapted for containing a working fluid and the other adapted for containing gas under pressure. Working fluid is provided in a volume between the nonpermeable internal sleeve and the composite pressure vessel wall. Further means are provided for withstanding harmful effects of radial flexing of the composite vessel wall under high pressures, and from stresses present in use in mobile applications such as with a hydraulic power system for a hydraulic hybrid motor vehicle. A method for pre-charging the device is also presented.

Abstract: A hydraulic pressure compensation system for valve actuator assemblies is described having particular application for subsea wellhead installations. The compensation system includes at least one valve actuator assembly having a housing that retains a reciprocable piston therewithin. The piston is spring biased into its fail safe configuration. The valve actuator assembly is hydraulically associated with an accumulator reservoir that defines a closed fluid reservoir and an open fluid reservoir that is exposed to ambient pressures. The two chambers are separated by a membrane. The valve actuator assembly is also operationally associated with a fluid pressure intensifier that boosts the ambient pressure of the accumulator so that an increased fluid pressure may be transmitted to the actuator assembly to bias the actuated valve toward its fail safe configuration. In a described embodiment, the fluid pressure intensifier comprises a housing that defines a chamber having a fluid inlet and fluid outlet.

Abstract: A compensation device for compensating a volumetric expansion of a medium during freezing has a receptacle provided in a structural component. The medium is contained in the receptacle. A sealing element is provided that delimits the receptacle. The sealing element is prestressed by a prestressing force provided by a pressure spring against the operating pressure of the medium.

Abstract: A liquid cooling system utilizing minimal size and volume enclosures, air pockets, compressible objects, and flexible objects is provided to protect against expansion of water-based solutions when frozen. In such a system, pipes, pumps, and heat exchangers are designed to prevent cracking of their enclosures and chambers. Also described are methods of preventing cracking in a liquid cooling system. In all these cases, the system must be designed to tolerate expansion when water is frozen.

Abstract: A hydraulic accumulator, particularly a piston-type accumulator, includes an accumulator housing (1) which defines a longitudinal axis (9), is provided with an opening that is concentric with the longitudinal axis (9) and is closed by means of a lid (11). The lid is secured in a form-fitting manner against axial forces by a wall portion (25) of the accumulator housing (1). The housing encompasses the lid and is radially deformed towards the inside. The hydraulic accumulator also includes at least one part (39) that is deformed perpendicular to the longitudinal axis (9) secure the lid (11) in a form-fitting manner against being twisted relative to the longitudinal axis (9).

Abstract: This invention relates to a fluid accumulator comprising a wall (2) encompassing a reservoir (1) for receiving the fluid, part of the wall being elastically deformable. The wall (2) of the fluid accumulator comprises a first wall portion (2A) that is made of a first elastically deformable composite, with fibrous reinforcement material applied in a first density, and a second wall portion (2B) that is made of a second composite with fibrous reinforcement material applied in a second density and an elastic deformability that is the same as or different from the elastic deformability of the first wall portion, the density of the fibrous reinfrocement material in the first and second wall portion (2A, 2B) being different.

Abstract: A hydroaccumulator, in particular a bladder accumulator, includes a pressurized container (1) and a separation element (5) located in the container to separate a gas chamber (7) lying adjacent to an inlet on the gas side from a fluid chamber (9) lying adjacent to an inlet on the fluid side inlet (3), having a fluid connecting sleeve (11) and a valve arrangement located in the connecting sleeve (11). The valve body (17) has a transversal bore (33). The valve body is pretensioned in an open position which allows the passage of fluid and can be displaced into a closed position by a displacement of the separation element (5). The interior surface (15) of the connecting sleeve (11) lies directly against the valve body (17) and guides the displacement of the body between the open and closed positions. The side of the valve body (17?) that faces the separation element (5) is configured as a planar plate extending partially into the fluid chamber (9).

Abstract: A hydraulic fluid reservoir (10, 10?, 10?, 10??) comprises a body 12, 12?, 12? 12??) defining a variable volume chamber having one end portion movable with the level of fluid in the chamber. A biasing member (18, 18?, 18?, 18??) acting on a traction rod (16, 16?, 16?, 16??) extending from the movable end portion restrains movement thereof under fluid pressure. The fluid pressure in the variable volume chamber advantageously counterbalances the force of reaction in the biasing member (18, 18?, 18?, 18??).

Abstract: A hydraulic accumulator A to be removably attached to a support member includes a liquid chamber R2b having a predetermined volume even when no pressurized operating liquid is accumulated, and communicating with a liquid inflow port Pi and a liquid outflow port Po, which are disposed below the liquid chamber R2b. A liquid-chamber-R2b-side end of an outflow passageway So connecting the liquid chamber R2b and the liquid outflow port Po opens to an upper portion of the liquid chamber R2b. Further, an inflow passageway Si connecting the liquid chamber R2b and the liquid inflow port Pi is coaxially disposed within the outflow passageway So, and a liquid-chamber-R2b-side end of the inflow passageway Si opens to the upper portion of the liquid chamber R2b.

Abstract: A piston-type accumulator includes a separating piston (13) displaced axially within a piston housing (1). The piston separates a fluid side (15) of the accumulator from its gas side (23), and has comprises two sealing areas (17, 25) offset relative to each other in the axial direction. The sealing areas are arranged on the circumference of the piston and are displaced along the inner wall surface of the accumulator housing. The accumulator housing (1) is provided with a ventilation device (31) between the sealing areas (17, 25) for discharging leakage passing through the sealing areas (17, 25).

Abstract: A replacement accumulator piston for various General Motors transmissions, which absorbs clutch apply fluid pressure to cushion the application of a clutch band against fluid shock is disclosed. The present pinless accumulator piston design eliminates the accumulator pin whereon the original equipment accumulator piston resides thereby resolving the problem of hydraulic leakage at the accumulator pin/piston interface. The elimination of the accumulator pin is accomplished by increasing the axial length of the piston sidewall or skirt, which permits the use of additional guide rings about circumference of the piston. The additional guide rings facilitate the reciprocating movement of the piston within the piston bore in the absence of the accumulator pin and also serve to maintain the hydraulic integrity of the accumulator. The pinless accumulator piston is a direct replacement for both the forward clutch accumulator, and the 1-2 gear and 3-4 gear accumulators in General Motors transmissions.

Abstract: An accumulator with a bellows dividing the accumulator into a pressure sealing chamber and a fluid flow-in chamber. A fluid inlet introduces fluid into the flow-in chamber. A bellows cap is attached to a movable end of the bellows and contains a throttling mechanism and chamber room for dampening sounds generated by pulsating waves. The throttling mechanism is positioned to oppose the fluid inlet.

Abstract: A pressure-stable cylinder comprises a cover having a dome shape groove and a through hole; an inner wall of the dome shape groove having threads; a cylinder having an opening and an opening section around the opening having a threaded tapered shape matching to the dome shape groove of the cover; the opening section of the cylinder being formed with a plurality of first washers; one end of the opening section having a coupling groove and a second washer; a bellow coupled to the second washer; a disk placed below the bellow; and a compressible spring placed between the disk and a bottom of the cylinder; the compressible spring resisting against the disk so that the cylinder has a predetermined pressure. In assembly, the washer and the bellow are steadily fixed to the coupling groove of the cylinder. The washers have an effect of draining-proof and air-tightness.

Abstract: A pulsation dampener apparatus and method for dampening pulses within a fluid flow line during well drilling operations. The pulsation dampener apparatus comprises a cylindrical body having an annular chamber, a piston slidably disposed within the annular chamber, a gas column within the annular chamber and a means of communicating pulses from the fluid flow line to the piston. The piston is operated against the gas column to dampen the pulses within the fluid flow line.

Abstract: In a metal bellows accumulator, a metallic bellows unit is disposed within a pressure space defined in a main shell, and one end of the metallic bellows unit is fixedly secured to one end wall of the main shell. The metallic bellows unit sections the pressure space into an outer chamber serving as a gas chamber in which a pressurized gas is enclosed, and an inner chamber serving as a liquid chamber communicating with a liquid port formed in the end wall of the main shell. A stopper (auxiliary shell) for limiting collapsing movement of the metallic bellows unit is disposed within the liquid chamber and has a communication passage hole. The liquid port always communicates with a liquid chamber to which an inner circumferential surface of a bellows portion of the metallic bellows unit is exposed via the communication passage hole.

Abstract: A bellows-type hydraulic accumulator includes a shell, a bellows unit, and a stay in order to accumulate pressurized liquid within a liquid chamber, divided into a fixed-volume liquid chamber and a variable-volume liquid chamber communicating with the fixed-volume liquid chamber via a communication port formed in the stay. A pipe is inserted into a liquid inlet/outlet port communicating with the fixed-volume liquid chamber, to thereby form an inflow passage inside the pipe and an outflow passage outside the pipe. A tip end of the pipe is located within the communication port of the stay with a predetermined radial clearance formed between the tip end and a wall surface of the communication port, to thereby enable pressurized liquid to be supplied to the variable-volume liquid chamber from the tip end of the pipe and to be discharged from the variable-volume liquid chamber to the fixed-volume liquid chamber via the radial clearance.

Abstract: A hydraulic accumulator, especially a piston accumulator, includes an accumulator housing (10) with at least one gas chamber (12) and a fluid chamber (14). These chambers are separated from each other by a separating element (16). At least one of these chambers (12, 14) can be filled with a pressure medium or at least partially emptied through at least one valve control unit (26) which has switching valves (28, 30). One switching valve (28) is accommodated in a corresponding valve location (29), and can be moved in the direction of movement of the separating element (16) from an opening position into closing position and vice-versa. Expensive line network between the hydraulic accumulator and the valve control unit is avoided. Sealing or leakage problems, such as are common in a line network, never occur. The valve control unit (26) is accommodated in a valve block (24) which is independent from the housing (10).

Abstract: An accumulator (1) capable of suppressing a hydraulic pressure vibrating noise in the range of a sealed gas pressure or below and being reduced in size, wherein an operating member (5) having a bellows (6) is disposed in a housing (2) to partition the inside of the housing (2) into a pressure sealed chamber (8) and a pressure inflow chamber (9) and a fluid inlet (15) for leading pressure fluid from a system side to the pressure inflow chamber (9) is formed in the end wall part (3a) of the housing (2), a chamber forming member (17) is fixed to the inside of the housing (2), and a chamber (18) and a choke (19) are provided between the chamber forming member (17) and the end will part (3a) of the housing (2).

Abstract: The method of providing a piston type accumulator with a controlled depth liquid shield on the top of a piston with seals separating a pressurized gas from the seals sealing the pressurized liquid comprising providing a portion of the gas in a chamber portion above said piston and a portion of the gas in a chamber portion not above said piston such that liquids accumulating in the chamber above the piston can be vented into the chamber not above the piston for venting to a location outside said chambers.

Abstract: The invention relates to a piston-type accumulator comprising a separating piston (13) which can be displaced axially within a piston housing (1). Said piston separates a fluid side (15) of the accumulator from the gas side (23) thereof and comprises two sealing areas (17, 25) which are offset in relation to each other in the axial direction thereof, said sealing areas being arranged on the circumference thereof and being displaced on the inner wall of the accumulator housing. The invention is characterized in that the accumulator housing (1) is provided with a ventilation device (31) between said sealing areas (17, 25) for discharging leaking means passing through the sealing areas (17, 25).

Abstract: A hydraulic accumulator A to be removably attached to a support member includes a liquid chamber R2b having a predetermined volume even when no pressurized operating liquid is accumulated, and communicating with a liquid inflow port Pi and a liquid outflow port Po, which are disposed below the liquid chamber R2b. A liquid-chamber-R2b-side end of an outflow passageway So connecting the liquid chamber R2b and the liquid outflow port Po opens to an upper portion of the liquid chamber R2b. Further, an inflow passageway Si connecting the liquid chamber R2b and the liquid inflow port Pi is coaxially disposed within the outflow passageway So, and a liquid-chamber-R2b-side end of the inflow passageway Si opens to the upper portion of the liquid chamber R2b.

Abstract: In an accumulator comprising a pressure vessel, a bellows dividing the interior of the pressure vessel into a gas chamber filled with pressurized gas and a liquid chamber which communicates with a liquid pressure circuit via a liquid introduction port, a stay member attached to the inner surface of the pressure vessel inside the bellows and provided with a communication port for communicating the interior and exterior of the stay member with each other and adapted to be closed by a part of the bellows to define a fully contracted state of the bellows, and a safety valve provided in the stay member, typically in the form of a weakened portion of the stay member, for selectively communicating the exterior of the stay member with the interior of the stay member. Thus, because the safety valve is not provided in the pressure vessel itself, the safety valve of the present invention would not affect the sealing capability of the pressure vessel.

Abstract: A bellows-type hydraulic accumulator includes a main shell defining a pressure space, and a bellows unit sectioning the pressure space into a gas chamber and a liquid chamber. An auxiliary shell is disposed inside the liquid chamber and fixed to the main shell. The auxiliary shell has an auxiliary liquid chamber communicating with a liquid port. A movable wall member is disposed in the auxiliary shell in order to section the interior of the auxiliary shell into a first interior portion communicating with the liquid port and a second interior portion communicating with the liquid chamber via a communication passage formed in the auxiliary shell.

Abstract: Disclosed is an accumulator comprising a cylindrical shell including a cylindrical portion, a partitioning member for partitioning the interior of the shell into a hydraulic chamber and a gas chamber, and a port including a hydraulic fluid flow path for communicating the exterior of the shell and the hydraulic chamber. The variation of the pressure of a hydraulic fluid flowing into the hydraulic chamber is accommodated by expansion and compression of a gas in the gas chamber according to expansion and contraction of the partitioning member. The port is approximately airtightly inserted into the cylindrical portion of the shell, and is welded to an outer circumference of the cylindrical portion by means of welding.

Abstract: A hydraulic fluid reservoir comprises a body defining a variable volume chamber having one end portion movable with the level of fluid in the chamber. A biasing member acting on a traction rod extending from the movable end portion restrains movement thereof under fluid pressure. The fluid pressure in the variable volume chamber advantageously counterbalances the force of reaction in the biasing member.

Abstract: A freezeless wall hydrant has a normally horizontal fluid inlet tube with an interior end and exterior end. A hollow valve fitting is rigidly secured to the interior end of the inlet tube for a connection to a source of pressurized fluid. A valve seat is located on an interior end of the valve fitting. An elongated hollow tube of a diameter less than the interior diameter of the inlet tube is positioned on the center line of the inlet tube and has inner and outer ends. A plug is rigidly secured to the inner end of the tube to close the inner end for fluid flow. A normally closed check valve is movably mounted in the tube to engage a valve seat on the plug, to open the tube for fluid therein under conditions of high fluid pressure in the inlet tube.

Abstract: A pressure accumulator has a housing having at least one pressure medium opening, a diaphragm chamber arranged inside the housing and having a side wall which is at least partially deformable, and a pressure medium chamber arranged outside of the diaphragm chamber, the pressure medium chamber at least partially being limited by a partially permeable material which allows an exit of gas from the pressure medium chamber but prevents an exit of a pressure medium from the pressure medium chamber.

Abstract: The method of providing a piston type accumulator with a controlled depth liquid shield on the top of a piston with seals separating a pressurized gas from the seals sealing the pressurized liquid comprising providing a portion of the gas in a chamber portion above said piston and a portion of the gas in a chamber portion not above said piston such that liquids accumulating in the chamber above the piston can be vented into the chamber not above the piston for venting to a location outside said chambers.

Abstract: An externally-mounted, quick-acting trigger assembly for firing blast aerators, air cannons, or the like. The trigger assembly is ideal for high temperature applications involving environmental factors such as excessive heat, humidity, and mechanical shock. The trigger comprises a symmetrical, ventilated housing that internally mounts a hollow piston. A plurality of vent orifices are radially disposed about the housing periphery, and normally covered by a resilient band forming a check valve. The trigger piston comprises a generally cylindrical base and an integral, generally conical bottom that is displaced into and out of contact with a mechanical valve seat. An air passageway through the piston is controlled by a deflectable spherical valve element that is captivated within the piston, for selectively blocking air passage through the piston by contacting an internal valve seat. This construction with internal air passageways facilitates trigger function.