Abstract: A system for preventing fouling of submerged hydraulic cylinder actuators includes a pneumatic line communicably connected to a protective bellows element surrounding the cylinder rod of the actuator mechanism. As the cylinder rod extends from the cylinder housing of the mechanism and the bellows element expands, filtered air is drawn into the bellows element. Water and accompanying contaminants are prevented from entering the bellows and interfering with operation of the hydraulic actuator mechanism.

Abstract: A pump comprising a pump housing member having a chamber with inner walls and an open end having a first area, the pump housing member comprises an enlarged surface surrounding the open end of the chamber. The pump further comprises a second pump housing member and a membrane element with a second area. The membrane element has a first central section having a third area with same size as the first area of the open end of the chamber. The membrane element is arranged on the pump housing element with the first central section positioned over the open end, forming a sealed chamber. A portion of the membrane element is slidably clamped between the enlarged surface and the second pump housing member.

Abstract: A piston-cylinder unit including a piston (103) that is fluid pressure supported and movable in a linear manner in a cylinder (2), wherein the cylinder (2), a face wall (116) of the piston (103) and a face wall (12) of the cylinder define a compression cavity (18) which is at a minimum size in a portion of a top dead center (TDC) of the piston (103), wherein the compression cavity (18) is connected in a fluid transferring mariner with a bearing gap (19) which is formed between a cylinder inner circumferential wall (14) and a piston outer circumferential wall (136), wherein a plurality of fluid outlet nozzles (32?, 34?) are arranged in at least one cross-sectional plane (Q2, Q3) of the cylinder (2) in the cylinder inner circumferential wall (14) along a circumference, which fluid outlet nozzles (32?, 34?) open into the bearing gap (19) and are connected with a supply conduit for a pressurized fluid, and wherein a plurality of fluid outlet nozzles (130?) which open into the bearing gap (19) are arranged in at l

Abstract: A fluid pump having a pump housing that includes at least one expansion joint, provides volume compensation, as needed, to adjust for changes in pressure in the pump housing. Various embodiments automatically and passively reduce static pressure in the pump housing associated with a freezing event, thereby preventing damage to the pump head. Volume compensation is achieved by employing, in each expansion joint, a dynamic seal that allows relative movement of two portions of the pump housing, and a bias that provides a selected counter-force to the movement of the housing portions. The subject pumps are particularly suited for use in automotive and other rugged applications, in which fluid pumps may experience recurring freezing events.

Abstract: An assembly and method is provided for reducing clutch wear due to centrifugal apply pressure within a clutch-apply cavity. The assembly comprises a rotatable clutch housing, a clutch-apply piston disposed within a clutch-apply cavity, and a balance piston. The balance and apply pistons define a balance cavity including a liquid fill channel and a dedicated air exhaust channel having a control radius configured to at least partially offset or compensate for the centrifugal apply force generated within the clutch-apply cavity when the clutch assembly rotates. The method includes configuring the balance cavity with an exhaust channel for exhausting fluid, and providing the exhaust channel with a control radius determined by the innermost radius of rotating fluid within the balance cavity as measured with respect to the centerline of rotation of the clutch assembly, the control radius being suitable for exhausting any excess of centrifugal balance force over centrifugal apply force.

Abstract: A device uses hydraulic actuation for the closure of a vessel by a rotation-symmetric reciprocating piston mechanism of an extremely compact type, which includes a reciprocating hydraulic piston and an intensifier piston, which are in each case moved in cylinders. The hydraulic piston is driven water-hydraulically and the intensifier piston pneumatically, these two forming a direct axial functional unit via a fluid, which is located in a chamber between the lower face of the hydraulic cylinder and the upper face of the intensifier piston. The upper face of the hydraulic piston forms at least partially the plug-type closure of the vessel or is rigidly connected to a closure element of the vessel.

Abstract: A method, system and apparatus for performing peritoneal dialysis are provided. To this end, in part, a pump for a dialysis system is provided. The pump includes a first chamber wall including a first aperture, a second chamber wall including a second aperture, a piston, at least a portion of which can move through the second aperture, the piston including a third aperture, and first and second membranes disposed between the first and second chambers walls. A vacuum can be applied through the first aperture to pull the first membrane towards the first chamber wall and can be applied through the third aperture to pull the second membrane towards the piston. The piston can thereafter move the second membrane.

Abstract: A membrane pump (104) with an operating membrane (1) delimiting a conveying space (2), and a supplemental membrane (3) arranged on the side of the operating membrane (1) facing away from the conveying space (2), with a membrane interspace (4) provided between the operating membrane (1) and the supplemental membrane (3) as well as with a pump drive for oscillating movement of the operating and the supplemental membranes (1, 3) in the same direction. The membrane interspace (3) is joined with at least one suction channel (7) for relieving pressure of the membrane interspace (4). The membrane interspace (4) is pneumatically joined through the at least one suction channel (7) with the suction side of this membrane pump (104). The membrane pump of the invention (104) has a high suction capacity without the problem of buckling of the elastic operating membrane (1) in the intake phase.

Abstract: The invention relates to a leakage oil return apparatus for a hydraulic motor. The apparatus is used for returning the oil leaked from the working pressure space of a motor (1) into a motor casing (12) from the casing (12) back to a return line (2) of the motor. Consequently, the return pump (5) driven by a shaft (3) of the hydraulic motor (1) has its suction side (7) connected with said casing (12) and its delivery side (6) conencted by way of non-return valves (4) with pressure and return lines (2) of the motor (1) in such a way that flow communication is established always with the line having a lower pressure. It is preferred that the return pump (5) have its delivery side (6) connected by way of a pressure proportional valve (8) with said casing (12).

Abstract: An improved plunger and barrel assembly is provided which includes a plunger reciprocally mounted in a cavity formed in the barrel and a leakage flow reduction device positioned in the cavity for reducing fluid leakage flow around the plunger thus increasing system efficiency. The leakage flow reduction device includes a sealing sleeve removably mounted in the cavity between the plunger and the barrel, which includes a bore for slidably receiving the plunger to form an annular clearance gap between the plunger and the bore. The sealing sleeve is designed to resiliently flex in response to fluid pressure forces to reduce the annular clearance gap so as to minimize fluid leakage through the annular clearance gap. The sealing sleeve is formed as a separate piece from the barrel to permit simple, low cost replacement. The sealing sleeve is preferably applied to a fuel pump having a pump plunger for pressurizing fuel in a high pressure chamber.

Abstract: A diaphragm pump having a simple structure for effectively preventing pulsation of liquid being discharged, which includes an air chamber connected to a head-side discharge hole of the diaphragm pump and having a discharge-side discharge hole, and thereby pipes are kept from being damaged by preventing the pulsation of the liquid, and the level of noisy can be reduced to a very adequate level.

Abstract: A device including a first moving part such as a piston (1) and a second moving part such as a connecting rod (2) with a coupling part (4) therebetween. A low-pressure compressible liquid lubricant feed system delivers a liquid into a chamber (10) with a variable volume between the second part and the coupling part, to form a pump supplying the joint interstice (16) to be lubricated, by a one-way connection (13, 15) and a resilient return member (11), wherein the interstice communicates with a cavity (17) with a fixed volume used as a liquid lubricant source. The volume, in relation to the pump displacement, enables a degree of deflection of the pump piston (3) while achieving a sufficiently high pressure and compensating for leakage.

Abstract: The fluid-pressure ram, for controlling a clutch release bearing for an automobile clutch, has two variable-volume control chambers which follow each other axially and comprise a primary chamber which is fed with pressurized fluid and which is axially delimited sealingly, to the front by a fixed base and to the rear by a movable wall integral with a shell, and a secondary chamber which is axially delimited sealingly, to the front by the movable wall and to the rear by the piston, the movements of the fluidtight movable wall bringing about a decantation of a fluid contained in an intermediate chamber to the secondary chamber, and vice versa, the said shell separating the intermediate chamber from the secondary chamber.

Abstract: A piston reciprocally movable within a cylinder is sealed to the cylinder wall by fluid at a pressure greater than those of the fluids on the opposed sides of the piston supplied to the space (18) between two seals (19, 20) operative between the piston and cylinder wall, an accumulator or auxiliary intensifier chamber (67) being provided from which overpressure fluid is supplied to the space between the two seals to regulate the pressure between them. The two seals between the piston and the cylinder wall can be constituted respectively by first (19A-19C) and second (20A-20C) groups or pluralities of separate seal rings selected as regards material and dimensions so as to perform specific functions.

Abstract: Unbalanced oscillatory pressures, developed on the power piston of hydraulic servoactuator systems cause vibrations on actuator housing supports. An unbalanced oscillatory force results, when two sides of the power piston are subjected to two unequal oscillatory forces induced by a disturbance. The two important disturbances are: pump flow rate oscillations, caused by power source torque oscillations; and, load oscillations. The invention is a hydraulic actuator connected in parallel to the power piston and designed to cancel vibrations by eliminating the unbalanced oscillatory pressure on the power piston. This is accomplished by designing the piston frequency of the invention, defined as tuning frequency, to be equal to the unbalanced oscillatory pressure frequency.

Abstract: An oilless reciprocating compressor for use in a refrigerated controlled atmosphere has an uncooled, fully sealed crankcase. A bypass tubing connects the interior of the crankcase with the inlet of the cylinders, so that blow-by is returned from the crankcase to the inlet of the cylinder for recirculation. In consequence no blow-by gas escapes into the controlled atmosphere. The device includes standard pistons, and has an improved cylinder head seal utilizing o-rings.

Abstract: A self-venting seal assembly for use in an ultrahigh-pressure pump is shown and described. In a preferred embodiment, a low-pressure seal is used to energize a high-pressure seal, the low-pressure seal having a "u" shaped cross-section, thereby creating a groove in a first end of the low-pressure seal. When the first end of the seal is exposed to pressurized fluid, it expands outwardly thereby substantially preventing the leakage of fluid past it. To the extent that any pressurized fluid does leak past the seal, which would act against a second end of the seal when the pressure on the opposite side of the seal drops, the seal compresses inwardly, thereby allowing the pressurized fluid to flow back past the seal.In a preferred embodiment, the high-pressure seal comprises a sleeve seal having an annular opening through which the plunger reciprocates, the sleeve seal being supported by a backup ring, the backup ring also having an annular opening through which the plunger passes.

Abstract: This invention relates to reciprocating piston machines which use the crankcase for pumping air or charge. The connecting rod with extension partitions the interior of the crankcase including the lower cylinder into two varying volumes during a portion of each revolution of the crankshaft. A unique feature is that the designer can choose the capacity of the crankcase pump independent of other significant design parameters such as the ratio length of connecting rod/stroke and the ratio stroke/bore.

Abstract: A fluid-powered actuator (42) has a body (11) which includes an end wall (16) provided with a through-opening (21). A piston rod (44) has an inner portion (44A) arranged on one side of the end wall within a pressurizable working chamber (24) of the actuator, has a penetrant portion (44B) passing through the end wall opening, and has an outer portion (44C) arranged on the other side of the end wall. The rod is configured such that the transverse cross-sectional area of the penetrant portion is greater than the transverse cross-sectional area of the outer portion so as to define an annular surface (46) which faces away from the actuator chamber. The improvement provides a seal assembly (43) for containing fluid leaking from the actuator chamber.

Abstract: A hydro-pneumatic pressure transformer with a storage piston fixed between storage oil and compressed air, which furthermore is centrally penetrated by a plunger piston, wherein, for the separation of oil from water, relief grooves are provided on the jacket face as well as in the wall of the central bore, which are connected with each other and are pressure-relieved via a ventilating bore leading to the exterior.

Abstract: An elongate tank for transport or for storage in bulk of semisolid and fluid materials, such as grease and oil. The tank has an outlet at one end thereof for discharging material contained therein, and has a generally cylindric interior surface. A generally cylindric piston is sized to slide in the tank and is movable in a direction toward the outlet thereby to place material in the tank through the outlet. The piston comprises a piston member and an elastic annular seal carried in a circumferential channel around the piston member. The seal has an annular base and an annular crown disposed radially outwardly of and joined to the base with a fluid chamber between the base and crown. The seal is expandable by introducing fluid into the fluid chamber.

Abstract: A high pressure die cylinder and manifold system including a plurality of die cylinders mounted on a manifold. Each die cylinder includes a cylinder body in which a piston rod and a piston is positioned for limited relative movement with respect to the cylinder body. A cup shaped piston sealing ring is mounted on the cylinder body for engagement with the piston rod and a cup shaped sealing ring is mounted on the piston for engagement with the cylinder body. A lubricant metering ring is mounted on the piston intermediate the sealing rings and the piston has a lubricant chamber that communicates with circumferentially spaced openings in the lubricant metering ring for delivering lubricant to the exterior of the sealing ring.

Abstract: A high pressure pump includes a housing having a pump chamber therein for receiving a pump piston, and a separate pressure housing having a liquid pressure chamber therein in fluid communication with a pump discharge flow line within an outlet housing. A force-transmitting piston is provided within the pressure housing and is movable along an axis substantially coincident with the central axis of the pump piston to place a desired load on each of a plurality of compression rods. The pump may be initially manufactured with the pressure housing, or a separate pressure housing may be added to an existing pump without modifying other pump components. According to the method of this invention, a control valve in a compression line is opened, the pump is activated, then the compression line is closed to maintain the compression rods under load.

Abstract: The present invention is drawn to an isolation system for separating two diverse fluid mediums from each other and, more particularly, an isolation system for prohibiting leakage of the diverse mediums around the peripheral surface of a piston movably mounted within a chamber. The present invention further relates to an improved multi-piston air-oil pressure intensifier employing the improved isolation system for separating and preventing leakage of the air and oil mediums during operation of the pressure intensifier.

Abstract: An air-powered actuator having a body with first and second ends, an axially transverse annular bulkhead positioned therebetween, and an output shaft with a splined exterior portion. The body includes first and second end walls with each end wall having a sleeve mounted coaxially within the body about the shaft and projecting axially inward within the body. A piston sleeve is disposed for axial reciprocating movement within the body. The piston sleeve has a pair of piston heads, an outer sleeve, and an inner sleeve. The outer sleeve is mounted coaxially within the body inward of the bulkhead and about the first and second sleeves to define therewith a fluid-tight outer chamber containing the piston heads, each positioned to an opposite side of the bulkhead to define four fluid-tight chambers and to which pressurized air is applied. Also defined is a fluid-tight inner chamber containing lubricating oil. The outer sleeve is attached to the piston heads for reciprocating travel therewith.

Abstract: A force applicator comprises a ram operable by fluid under pressure. A pressure pad (7) is located between one movable part of the ram (3) and the load (9) and means are provided which enable relative movement to take place between the pressure pad and the ram in a direction at right angles to the direction of operation of the ram. The means may take the form of a fluid chamber (15) between the pressure pad and the ram or a disc of PTFE between them.

Abstract: The present invention relates to a sealing device provided between a piston rod of a Stirling cycle engine and a variable volume chamber. The sealing device is provided with an arrangement so as to equalize pressures between a seal chamber and the variable volume chamber of the Stirling cycle engine. By equalizing pressures between the respective spaces, an overpressure is prevented which would otherwise distort the seal and permit oil to be carried into the working volume of the Stirling cycle engine.

Abstract: A hydraulic cylinder apparatus is used by connecting an external pressure source with extension and contraction-side liquid chambers defined by a cylinder, a piston sliding in the cylinder and a piston rod integral with the piston. The apparatus includes seal members provided with the extension and contraction-side liquid chambers and formed to enable liquid to leak through clearances between the seal members and the parts disposed opposite to the seal members. Liquid leaked from the extension and contraction-side liquid chambers is received by a receiving chamber which is formed so as to change its volume with the movement of the piston rod.

Abstract: A shaft alignment system for pumps which utilizes a clamp for holding a reciprocating shaft to a piston in an abutting relationship. The clamp can be loosened and retightened after the piston, which is attached to the reciprocating shaft, is inserted in a cylinder. Forces induced on the piston after insertion in the cylinder cause the piston and shaft to be realigned. Resecuring the reciprocating shaft assembly to the piston assembly causes the system to be precisely aligned in a transverse direction.

Abstract: A self-flushing fluid seal assembly is provided to prevent particle intrusion into the main seal around a slurry pump shaft. The assembly includes an annular tube concentrically disposed about the pump shaft and forming a chamber. The volume of the chamber is made variable by a plunger comprising an enlarged diameter portion of the pump shaft movable relative to the chamber during the power and return stroke of the pump. Flushing liquid is delivered to the chamber by means of a feed line extending through the shaft. A check valve provided in the feed line opens to allow the inward flow of flushing fluid from the feed line to the chamber as the chamber expands. Conversely, the check valve closes and a secondary shaft seal is provided to prevent the reverse flow of flushing fluid as the chamber contracts on the return stroke.

Abstract: A seal assembly is arranged to contain leakage of hydraulic fluid passing between a wall opening and a penetrant rod portion passing through the opening. The seal assembly includes a sliding-seal member mounted on a portion of the rod for sliding movement toward and away from an abutment surface and a non-sliding flexible-seal member arranged between the body and the sliding-seal member. The body, flexible-seal member, sliding-seal member and rod define a sealed chamber into which such fluid will leak. The chamber communicates with a fluid reservoir through a oneway check valve. The sliding-seal and flexible-seal members are arranged in parallel with one another. In one embodiment, a spring urges the sliding-seal member to move toward an abutment surface provided on the rod. In another embodiment, movement of the sliding-seal member relative to the body is limited by facing abutment steps.

Abstract: This invention relates to a pump arrangement (54) for use in a linear fluid operated device having a reciprocating piston (14) separating a first active fluid chamber (30) and a second chamber (32) which eliminates the problem associated with fluid leakage buildup developing in the second chamber. The pump arrangement (54) is connected to the reciprocating piston (14) and pumps leakage fluid present in the second chamber (32) from the second chamber (32) and into the first chamber (30) in response to a force of a preselected minimum magnitude being applied to the pump arrangement (54). Thus, the problems of inefficient linear fluid operated device operation, reduced piston stroke length, external fluid leakage, and erratic piston travel speed are eliminated. The pump arrangement (54) is particularly suited for use in a single acting linear hydraulic jack (12) such as used on a material handling vehicle.

Abstract: A compressible bellows surrounds a piston rod of the hydraulic cylinder of a hydraulic elevator. The lower end of the bellows surrounds a liquid receiving recess in the gland box of the cylinder and, when a sealing ring on the piston rod closes and compresses the bellows, the leaked hydraulic fluid is discharged from the recess, via a ball check valve, and a return tube to a sump.

Abstract: This disclosure relates to an apparatus for use with a piston cylinder assembly and includes one or more rod scraper elements employed for the removal and retention of any fluid adhering to the surface of the piston rod during its operation, which fluid if desired may be processed for reuse.

Abstract: A sealing device between a reciprocator and a stationary encircling housing comprises first and second rolling diaphragms at opposite ends of the reciprocator and exposed to higher and lower pressures, respectively, diaphragm-supporting liquid in first and second chambers in the respective diaphragms, and pumping means which, owing to the reciprocation, pumps liquid from the second chamber to the first. This means comprises an annular seal carried by the reciprocator, sliding on the housing and acting as a piston and as an inlet non-return valve, and another annular seal carried by the housing, sliding on the reciprocator and acting as an outlet non-return valve.

Abstract: Disclosed is a leak retriever for the packing gland on oil well pumps. The leak retriever has a reservoir disposed about the packing gland to collect oil which leaks through the gland and an auxiliary pump which is mounted in the reservoir and connected to pump all oil collected back into the discharge line for the well. The auxiliary pump is mounted in the reservoir so that any leaks from the auxiliary pump are also collected by the reservoir, and is driven by a plate on the polish rod of the well pump driving apparatus. In the first form the reservoir is clamped onto the packing gland housing below the cap nut, and in the second form it is made integral with the cap nut.

Abstract: A rotary hydraulic jack having two jack compartments, comprising a rotary hydraulic joint for the supply of hydraulic liquid to and the evacuation of hydraulic liquid from at least one of the compartments. The hydraulic joint comprises a fixed, hollow cylindrical part and a rotary part supported by bearings with a narrow annular gap between itself and the fixed part. A passageway leads to said compartment and has a portion in each of the fixed and rotary parts, the passageway portion in the rotary part being equipped with at least one non-return device for hydraulic liquid supplied to said compartment. A groove is provided in at least one of the fixed and rotary parts and communicates with the passageway portions in the fixed and rotary parts. Means is provided for supplying gas under pressure to the annular gap betwen the fixed and rotary parts for the purpose of expelling residual oil from the gap after the supply of hydraulic liquid under pressure to said compartment via the passageway has been completed.