Abstract: A piston pump for dispensing fluid from a reservoir, an improved vacuum relief arrangement in which a passageway for flow of air from the atmosphere into the reservoir is provided at least in part through a piston-forming element of the piston pump.

Abstract: An easy-to-disassemble pump with a replaceable, ergonomic shroud is contemplated. The pump components snap-fit and allow the user to easy access and clean its interior. Further, the internal components ensure sufficient suction is provided to minimize or avoid entrapment of fluid on exposed portions of the pump.

Abstract: A pump assembly comprises a pump main body having a first cavity and a press rod. The press rod has a rod body and a piston portion in which the rod body is slidably provided in the first cavity in a penetrating manner and one end thereof extends out of the first cavity. The piston portion is connected to the rod body and is located in the first cavity to divide it into a first gas cavity and a second gas cavity, one or more of which are sealed cavities. Since the piston portion can rebound under the resultant force of a gas pressure in the gas cavities, the pump main body does not need a spring for rebounding the rod body. Accordingly, the pump assembly can be entirely made of a plastic material, and no metal material is mixed, so the pump assembly is easily recycled.

Abstract: An air pump has a body, a piston rod and a seat cap assembly. The body has an outer protrusion and a first engaging part. The outer protrusion protrudes from the body. The first engaging part is longitudinally mounted on the outer protrusion. The piston rod is inserted into the body. The seal cap assembly has a top cover and a sleeve. The top cover is movably mounted on the piston rod. The sleeve is mounted on the body and has a retaining rib and a second engaging part. The retaining rib protrudes from an inner surface of the sleeve and abuts against a retaining surface of the outer protrusion. The second engaging part is longitudinally mounted on the inner surface of the sleeve and is engaged with the first engaging part of the body. Therefore, the relative rotation between the body and the sleeve is prevented.

Abstract: A piston type pumping apparatus comprises a vertically oriented cylinder having a top and a bottom with a first aperture. There are first and second passageways for liquid in the cylinder at the top and bottom respectively thereof. A piston is reciprocatingly mounted within the cylinder and has an area against which pressurized fluid acts in the direction of movement of the piston. A hollow piston rod is connected to the piston and extends below the piston and slidably through the first aperture. There is a reload chamber below the cylinder. The piston rod extends slidably into the reload chamber and has a third passageway for liquid communicating thereto. A first one-way valve is located in the third passageway. There is also a fourth passageway that extends from the reload chamber to a source of liquid to be pumped and a second one-way valve therein.

Abstract: Embodiments are described for engaging a pumping cartridge with a pump drive. In certain embodiments, the cartridge, including a cylinder and a movable piston assembly, is initially assembled or subsequently positioned so that the distance between the attachment point on the piston assembly for coupling to a drive assembly, and a reference point on the cylinder, is greater than the maximal distance that will be encountered during normal oscillation of the piston during use. The cartridge, in certain embodiments, may be pressed into a drive assembly that immobilizes the cartridge and couples the piston assembly to the driveshaft. In certain embodiments, when the cartridge is fully inserted into the drive assembly, the piston is pressed into the cylinder sufficiently to establish a selected distance so that the piston shaft is in the proper position to engage with a coupling mechanism carried on the driveshaft.

Abstract: A double string pump transports liquids to the surface of a hydrocarbon well including a hydrocarbon well that is producing both natural gas and liquid fluids. The double string pump includes a hollow tube that raises and lowers the plunger and carries the liquids to the surface and an outer tube receives liquids down into the well to lubricate the moving parts and flush particles from areas prone to wear and back toward the production tube. The natural gas is produced through the annulus between wellbore casing and the outer production tubing string.

Abstract: The cryogenic fluid generator includes at least one pump assembly having an actuator mounted to a container assembly. A pump assembly housing includes a longitudinal positioning opening and a pressurization cavity at a distal end terminating with a pump assembly outlet. An internal check valve assembly includes a shaft positioned within an opening of the pump assembly housing that extends into the pressurization cavity. The shaft is attached to the actuator and includes a longitudinal guidance slot; a fluid passageway; and, an internal sealing surface. A positioning bar assembly is positioned within the guidance slot. A connecting rod is securely connected at a first end to the positioning bar assembly, the connecting rod being positioned within the fluid passageway and terminating with a flow inhibiting element. A seal is positioned between the pump assembly housing and the check valve to provide a closure for the pressurization cavity.

Abstract: Apparatus (10) for harnessing ocean wave energy and for converting the harnessed energy to high pressure sea water, typically above 100 psi and preferably above 800 psi. The high pressure seawater generated by the apparatus (10) can be piped to shore for use in any appropriate purpose. The apparatus (10) comprises a float (12) buoyantly suspended within the body of seawater (1) and a pump (13) operatively connected to the float (12). The pump (13) comprises an intake chamber (47), a discharge chamber (49) and a piston (61) extending between the intake and discharge chambers (47, 49). The piston (61) comprises a tube (63) having a flow passage (102) extending between the intake and discharge chambers (47, 49). The piston (61) and discharge chamber (49) cooperate to define a pumping chamber (100) adapted to undergo expansion and contraction in response to reciprocatory motion of the piston. The piston (61) is operatively connected to the float (12) to be driven by upward movement of the float.

Abstract: A rotary pressure production turbine for pressurizing a hydraulic fluid is disclosed comprising a plurality of piston assemblies. Each piston assembly comprises a hollow needle piston shaft having through which hydraulic fluid is moved from a low pressure volume to a high pressure volume as the piston shaft moves in a first direction. A rotary actuator actuates each piston shaft. From the high pressure volume, hydraulic fluid is moved to a common high pressure header and delivered to an aspirated accumulator where the fluid can be stored and subsequently utilized. In some embodiments, the fluid is utilized to operate an electric generator for use in a hybrid-electric vehicle. In some embodiments, the rotary actuator is driven by an internal combustion engine, while in others the rotary actuator is driven by a vehicle drive train in a regenerative braking application.

Abstract: The invention relates to a piston pump for conveying fluids. The piston pump includes a piston, and a pressure chamber located between an intake valve and a discharge valve. The intake valve is arranged between the pressure chamber and a low-pressure zone of the piston pump. The intake valve has a valve body, a closing element, a device for preloading the closing element, and a device for fastening the intake valve to the piston. The fastening device encompasses at least two fastening elements which protrude from the valve body toward the piston. The fastening elements are positioned at a distance from one another, and are fitted with inlets therebetween for supplying fluid. The invention further relates to a piston pump having an intake valve without a spring-biased element.

Abstract: A floor pump includes a base; and a cylinder assembly having a first end coupled to the base and a second end, with a cross-sectional area of the first end of the cylinder assembly being larger than the second end of the cylinder assembly. A linkage assembly is partially disposed in the cylinder assembly and communicates with the base. A hose has a first end coupled to the base and communicating with the linkage assembly and a second end coupled to a thing desired to be inflated.

Abstract: An air pump, including: two cylinders, a big one and a small one, which are telescopically fitted to each other. A head connects with the outlet end of the small cylinder. A pressure relief valve connects with the outlet end of the big cylinder. A first piston is fixed at the inlet end of the small cylinder and placed in the big cylinder. A first pipe, has one end fixed on the outlet end of the big cylinder, and the other passes through the first piston and placed inside the small cylinder. A first chamber with a passage communicating with the first pipe forms therein between the inside wall of the big cylinder and the outside wall of the first pipe. A second pipe, one end fixed at the outlet end of the small cylinder and communicating with the head in one-way air admission, has the other fit into the first pipe in a telescopicing way and communicating with it. A second piston, which is placed inside the small cylinder, fixes at the other end of the first pipe and the second pipe goes through it.

Abstract: A fluid drawing device (10) comprising a hand pump (11) connected to a fluid reservoir (12). The reservoir (12) has an inlet/outlet orifice (18) through which fluid can be drawn into and expelled from the reservoir (12). The pump (11) comprises a squeeze bulb (13) with an air release valve (14) in its wall and an air intake valve (15). Compressing the bulb (13) releases the air to the atmosphere through the release valve (14), subsequent decompression of the bulb (13) draws air through the intake valve (15) from the reservoir (12) reducing the pressure in it to draw fluid through the orifice (18) into the reservoir (12). Pushing a plunger (24) slidably housed within the reservoir (12) expels the fluid out through the orifice (18).

Abstract: A portable air pump includes a tubular body, a barrel, a piston mechanism, a head, and a dispensing head. The tubular body has an upper cover having air inlet holes and a sealed bottom cover. The barrel has an air passage running through it along its axis direction. The piston has a center hole and a through hole, and a check valve is in positioned between the second end of the barrel and the bottom end of the piston. As the tubular body is moved in relation to the barrel away from the head, air flows into the tubular body through the air inlet holes and to the bottom of the tubular body through the through hole. Air is prevented from flowing out through the center hole of the piston by use of a check valve disc. As the tubular body is moved in relation to the barrel towards the head, air in the bottom of tubular body flows into the air passage of the barrel through the center hole, and out through the head and the dispensing head.

Abstract: A pump comprising a tubular body delimiting internally a metering chamber and comprising an inlet orifice, an inlet valve, a stem mounted so as to be able to move inside the body and comprising an actuation tube delimiting an outlet duct, an insert assembled to the actuation tube and comprising a base placed inside the metering chamber and facing the inlet orifice, and a discharge orifice, an annular piston mounted so as to slide inside the body and on the stem, the piston and the base comprising annular surfaces suitable for forming a discharge valve, a ball-and-socket joint being arranged between the insert and the actuation tube.

Abstract: A fluid dispensing system includes a pump assembly for pressurizing a low cost container, the container non reversibly connected to a coupler module. A wand assembly is releasably connected to the coupler module. A discharge conduit fluidly connects the wand assembly to the container to displace a check valve in the pump assembly to permit flow from the pump assembly. The wand assembly includes a grip body slideable relative to the discharge conduit between a retracted storage position and an extended operable position.

Abstract: To provide an efficient piston pump having a small number of parts and simple assembly steps, and consuming less current in achieving a relatively low ultimate pressure. The piston pump comprises: a suction port (28) through which gas sucked by varying the volume of a pump chamber (22) defined by a cylinder (12) and a piston (14) fitted in the cylinder (12) passes as the piston (14) is reciprocated, an exhaust port (20) through which the gas discharged by varying the volume of the pump chamber (22) passes, a suction valve (26) installed in the suction port (28) disposed on a piston top, and an exhaust valve (18) installed in the exhaust port (20) disposed on a top of the cylinder (12).

Abstract: Pumping cartridges useful for medical and surgical pumping and infusion procedures. In one aspect, a series of pumping cartridges include cylinders and pistons which have a sealing component including a circumferential, flared sealing flange and can be configured to enable the pumping cartridge to generate high liquid pumping pressures. Many of the pumping cartridges can be configured to be detachable from a pump drive unit and disposable after a single use. Some pistons include or at least partially form a valve and/or are relatively movable with respect to a connected piston rod. Valves include a valve seat and a movable sealing element able to create a seal capable of withstanding differences in fluid pressures thereacross of at least about 1,000 psi. The movable sealing element is concave in shape, and may be curved for improved sealing performance. Methods for pumping or infusing a liquid for delivery to the body of a patient or a surgical or medical instrument.

Abstract: To improve sealing efficiency in a pump withdrawing liquid from a supply container (1) and to minimize the liquid residue in said container, the pump is designed to include a cylinder (5), a hollow plunger (6) configured within said cylinder, an external accessory pipe (7) configured at least partly within said plunger, and a feed pipe (8) configured at least partly within said external, accessory pipe, the internal feed pipe (8) being displaceable relative to the external accessory pipe (7) which in turn is displaceable relative to the hollow plunger (6).

Abstract: The metering device for a liquid medium comprises a cylinder and a piston operatively disposed therein to define a metering chamber ahead of the piston. The outlet end of the cylinder is open and closed by an evacuation valve. The piston is driven forwardly through a working stroke to force the liquid medium in the metering chamber out of the chamber and past the evacuation valve. A check valve located in the metering chamber moves from a closed to an open position on each working stroke to preclude entrapment of air in the metering chamber and thus provide for more accurate metering. The metering device may include means to regulate the length of the working stroke.

Abstract: An apparatus for draining reservoirs includes a pump disposed in contact with a lower surface of the vessel to be drained, wherein the pump is connected to a discharge pipe inserted into the vessel through an insertion tube connected to a retrofit assembly of the vessel. The apparatus also includes seals within the insertion tube and within the discharge pipe to prevent gases from within the vessel from passing through the insertion tube and discharge pipe and into the atmosphere. An expansion joint unit attaches to the discharge pipe to prevent the rotation of the pump relative to the discharge pipe. The expansion joint unit also maintains the pump in substantial contact with the lower surface of the vessel even when thermal expansion causes the vessel to expand and the position of the discharge pipe to lift.

Abstract: Proposed is a radial piston pump with a pump body, in which pistons and cylinders are circumferentially arranged about a driven eccentric, which the pump possesses a faceted slip ring (9) assembly which has an inner diameter and a polygonal outer diameter, the polygon consists of straight, axial parallel surfaces (13), the number of which represents the number of pistons (2) contained in the radial piston pump.

Abstract: A positive displacement pump for pumping fluids from a downhole formation to the earth's surface is provided. The pump first comprises a plunger. The plunger is reciprocated axially within the wellbore by a linear actuator, such as a submersible electrical pump, in order to form an upstroke and a downstroke. A pump inlet is disposed near the bottom end of the plunger, while a pump outlet is disposed near the top end of the plunger. The pump is configured such that it is able to pump a first volume of fluid upward within the wellbore during the pump's upstroke, and a second volume of fluid upward within the wellbore during the pump's downstroke. Thus, the pump is “double-acting.

Abstract: The invention concerns a fluid pump with a cylinder, piston and check valve for compressing the fluid having a high-pressure seal for precluding leakage of pressurized fluid. Any leakage from the high-pressure seal feeds back into an inlet area of the pump and recycles through the pump instead of leaking externally.

Abstract: A reciprocating compressor includes a suction port, through which a working gas is taken into a cylinder volume, which is closed and opened by a suction valve, and a discharge port, through which the working gas compressed by a reciprocating piston is emitted toward an end use, which is closed and opened by a discharge valve, wherein the maximum discharge pressure determined by a compression ratio which is calculated by the ratio of the cylinder volume in a case where the piston is located at the bottom dead center position and the cylinder volume in a case where the piston is located at the top dead center position, is set so as to be compatible with the demand pressure of said gas end use.

Abstract: In a reciprocating compressor including a piston slide-inserted into the compression space of the cylinder, having a gas path therein, inducing a fluid into the compression space through the gas path and varying a volume of the compression space while performing a linear reciprocating motion with a mover of a reciprocating motor; a suction valve combined with the front end of the piston detachably and adjusting suctioning of the fluid into the compression space; and a discharge valve combined with the front end of the piston detachably and opening/closing the compression space of the cylinder in the linear reciprocating motion of the piston, a suction valve assembly of a reciprocating compressor includes an elastic member for absorb impact of the suction valve in clash and a combining member consisting of a head portion having a width so as to be overlapped with part of an opening/closing portion of the suction valve or a retainer and a valve seat, and accordingly a reliability of the compressor can be improv

Abstract: The present invention relates to petroleum recovery operations, and more particularly, to the use of pulse technology to enhance the effectiveness of waterflooding operations. The systems of the present invention generally comprise an injection means for continually injecting a fluid into the subterranean formation, and a pressure pulsing means for periodically applying a pressure pulse having a given amplitude and frequency to the fluid while the fluid is being injected into the subterranean formation.

Abstract: An easily operable telescopic pump includes a first cylinder, a second cylinder, a grip and a nozzle. The second cylinder is inserted in the first cylinder. The grip is communicated with the second cylinder. The nozzle is communicated with the grip. A pipe extends through the grip and includes an end inserted in the second cylinder and an opposite end connected with the nozzle.

Abstract: A downhole pump having a barrel with a reciprocating plunger therein has at least one valve. The valve has a cage, a seat and a ball. The cage has a passageway extending between two ends, with the passage including a ball chamber. The ball chamber is between a perforated member and a stop. The ball is located in the ball chamber between the perforated member and the seat, which abuts the stop. The ball is movable along a raceway. The raceway has ribs with channels therebetween. The raceway skews away from a longitudinal axis of the ball chamber from the seat toward to the perforated member. The raceway can be made of a material that is either harder or softer or the same as the hardness of the inner wall of the ball chamber. In another embodiment, the valve has a throat with a stop for receiving a seat. The ball chamber has portions that are hardened. The clearance between the ball and the hardened portions of the ball chamber is at least twice as large as the clearance between the ball and the throat.

Abstract: A suction valve assembly of a compressor includes: a piston disposed movable in a cylinder forming a compression chamber, having a suction passage for sucking a fluid and a valve seat formed at a front side thereof; a valve body contacted to the valve seat to open and close the fluid, of which a front side making a portion of the compression chamber is formed hermetical; a support rod inserted into a rear portion of the valve body and fixed at one side of the piston and supporting the valve body to be moved in a certain range; and a release preventing unit formed between the valve body and the support rod to prevent the valve body from releasing from the support rod. A guide groove inside a compression chamber is removed to prevent generation of a dead volume, thereby improving an efficiency of a compressor.

Abstract: In a suction valve apparatus of a reciprocating compressor including a piston having a gas passage at which gas flows inside its body portion, a valve seat formed at an end of a piston body to open the gas passage and a step face formed so as to have a thickness inward from the valve seat and have a plurality of gas through holes and a mounting through hole, and a valve cone having a detachable coupling portion formed extendely from a cone portion corresponded to the valve seat of the piston and inserted into the mounting through hole of the step face of the piston so as to be movable, a re-expansion loss can be reduced by minimizing a dead volume of a suction gas valve, an efficiency of a reciprocating compressor can improve by reducing a heat transmission loss by sucking refrigerant gas through the plurality of gas through holes of the step face from the gas passage.

Abstract: A pump assembly for mounting a high-pressure oil pump on an internal combustion engine where the pump in the assembly is mounted in a closed chamber and a solenoid controlled valve is mounted outside of the chamber.

Abstract: A pneumatically operated oil pump comprises an outer tube for extending into an oil tank and a sucking tube moveably arranged within the outer tube. The sucking tube includes one-way valve establishing an airtight arrangement with respect to an inner wall of the outer tube. An air operated device is arranged on top of the outer tube and interconnected to the sucking tube located within the outer tube. The device includes an upper operating chamber and a lower operating chamber intercommunicated with an air pipe. The device further includes a movement reciprocally moved within the device when compressed air is introduced into the device so as to move the sucking tube reciprocally.

Abstract: A valve fastening structure of a reciprocating compressor is provided. The valve fastening structure of the reciprocating compressor includes a piston, which is combined with a moving magnet of a driving motor and is in a linear reciprocating motion inside a cylinder and in which a refrigerant channel is formed in the direction of the reciprocating motion, a suction valve arranged in the leading end of the piston, the suction valve for opening and shutting the refrigerant channel of the piston, and magnets inserted into and fixed to the leading end of the piston, the magnets for fixing the suction valve by magnetic force. It is possible to minimize dead volume in the cylinder and to easily control the stroke of the piston by establishing the suction valve as the cardinal point during the controlling of the stroke of the piston. Accordingly, the efficiency of the compressor is improved.

Abstract: An electromagnetic compressor capable of reciprocating a piston to suck in and compress a gas by the force of an electromagnet and the resilient force of a return spring and a manufacturing method therefor are provided. The compressor includes a cylinder assembly including a front cylinder portion, a rear cylinder portion, and a center hole capable of storing the piston for reciprocation and having a working chamber defined by means of the piston, and an electromagnet located between the front cylinder portion and the rear cylinder portion and capable of actuating the piston. The cylinder assembly and the electromagnet have an integral structure molded from a resin in a manner such that the internal passage is hermetically sealed with respect to the electromagnet and the electrically conductive member.

Abstract: A positive-displacement pump (lifting pump) comprises a pump housing with a pump chamber having an inlet and an outlet passage controlled by an outlet check valve; a displacement member which delimits the pump chamber in one direction of movement of the displacement member and which is reciprocable in the pump chamber within a stroke region and includes a second check valve opening into the pump chamber within a stroke region and includes a second check valve opening into the pump chamber and disposed in a passage between the inlet and the pump chamber; and an actuating mechanism for repetitively reciprocating the displacement member in the pump housing within the stoke region.

Abstract: A high-volume low pressure hand operated air pump comprised of a tube body with a plunger shaft inserted into one end thereof and a check valve at the other end thereof with a floating seal secured to the internal end of the plunger shaft comprised of a captured double sided annular disk having a closed cell foam plastic seal on one side thereof and a plastic stiffener of the same plastic material integrated thereto for supporting the foam sealing side thereof

Abstract: An improved travelling valve has a ball which is positioned on a seal stem, so that the ball is reliably centered when seated on the valve seat, reducing damage to the ball and seat from improper seating and providing increased efficiency for deviated or non-vertical pumping operations and the pumping of highly viscous fluids such as heavy crude. The improved travelling valve is constructed so that a lower portion of the valve rotates during pumping, and thereby imparts rotational movement to the fluid passed therethrough. Such rotational movement of the valve and fluid helps reduce gas lock, and reduces damage to the ball, seat, and valve exterior from impurities in the pumped fluid. Preferably, rotational movement is caused by angled channels in an interior portion of a vein rotator positioned at the bottom of the travelling valve, working in combination with angled channels in the seal stem.

Abstract: The radial piston pump possesses a pump housing in which a plurality of cylinder bores are provided having pump pistons placed therein which can be driven by a cam. Further, an arrangement is provided in each pump piston (3) wherein the inlet or the outlet, or both the inlet as well as the outlet of the fluid in each cylinder bore, is controlled.

Abstract: A container includes an integral outlet tube that functions as a cylinder. A siphon mechanism including an elongated tube with a flexible seal on the outside surface of the tube functions as a piston. Fluid trapped inside the cylinder by a check valve is forced up and over the side of the container by downward movement of the piston inside the cylinder initiating the siphoning of further fluid from inside the container.

Abstract: The present invention relates to a linear compressor, and in particular, to a linear compressor which is capable of decreasing the specific volume of a sucked refrigerant gas by decreasing the amount of the refrigerant gas to be introduced into a suction opening of a hermetic vessel thereby to be sucked into a cylinder, which is to be mixed with a high temperature refrigerant gas with which the hermetic vessel is filled, and decreasing the suction loss of a refrigerant gas to thus improve the performance efficiency of the compressor and reduce noise generated during the suction of the refrigerant gas by preventing some of the refrigerant gas to be leaked out to the inner space of the cover.

Abstract: A double-acting reciprocating motor with uni-directional fluid flow path comprises a piston disposed within a cylinder. A first chamber is defined by the cylinder space between the piston and a cylinder base. A second chamber is defined by the cylinder space between the piston and a cylinder head. Fluid is introduced into the motor through an inlet port and into the first chamber. A pass-through valve controls the flow of fluid from the first chamber to the second chamber. An outlet valve regulates the draining of fluid from the second chamber through an outlet port. The outlet port and the inlet port are associated with opposite ends of the motor. Differential fluid pressure urges the piston towards the cylinder head when the pass-through valve is closed and the outlet valve is open. The piston surface facing the second chamber is larger than the piston surface facing the first chamber, so the piston moves towards the cylinder base when the pass-through valve is open and the outlet valve is closed.

Abstract: An axial plunger pump includes a shaft having a swash plate effecting swing motion and transmitting driving force from the outside, plungers reciprocate by the swing motion of the swash plate. A cylinder block has cylinders formed so as to open on the side of the swash plate, with the plungers inserted therein. Passages in the block supply refuel to the cylinders. A body combined with the cylinder block encloses the swash plate. Sealing members are arranged between the plungers and the cylinders on the swash plate side of the passages formed in the cylinder block for sealing gaps between the plungers and the cylinders, respectively.

Abstract: A hand pump has a tubular pump housing with a longitudinal axis. A piston with a peripheral seal reciprocates along the axis to compress air against a sealed end of the housing. A tubular plunger nested in the housing connects to the piston to reciprocate the piston and compress the air. A flexible hose is placed in fluid communication with the compressed air. The hose is coiled to fit entirely within the tubular plunger during storage. A removable handle is inserted through a distal end of the plunger to make it easier to reciprocate the plunger. The handle, tire repair tools and materials, and other items can be placed inside the plunger for storage, and enclosed by placing an end cap on the pump housing.

Abstract: A piston and seals for a reciprocating pump improve pumping of subterranean fluids containing fine solids to surface. The pump comprises a pump barrel and piston. The piston is suspended from a reciprocating rod string or from reciprocating production tubing. The barrel is held stationary relative to the casing of a well. A standing valve is located at the bottom of the barrel. The piston and travelling valve are located at the bottom of the piston rod for minimizing the dead-space between standing and travelling valves. Upper and lower stacks of hydraulic piston seal rings are positioned on the piston above and below the travelling valve for minimizing piston height. Each seal has radially flared lips at its leading edge. The piston has spaced grooves formed therein, corresponding to the seal ring flared lips.

Abstract: A reciprocating pump is provided for pumping subterranean fluids containing fine solids to surface. The pump comprises a pump barrel, piston and piston rod. The piston rod is suspended form reciprocating production tubing. The barrel is anchored in the casing of a well. A standing valve is located at the bottom of the barrel. The piston and travelling valve are located at the bottom of the piston rod for minimizing the dead-space between standing and travelling valves. Upper and lower stacks of hydraulic piston seal rings are positioned on the piston above and below the travelling valve for minimizing piston height. Each seal has radially flared lips at its leading edge. The piston spaced grooves formed therein, corresponding to the seal ring flared lips.

Abstract: The invention relates to a high pressure reciprocating pump, for a fuel injection system of an internal combustion engine, having at least one piston, which is displaceably supported in a piston guide provided in a housing and therein defines a work chamber. Supported in the housing is a drive shaft, on which a crank element is provided on which a stroke ring, is not rotatable in the housing. The crank element is rotatably supported, the stroke ring has a slide bearing face, associated with the piston on which face the piston is supported with a slide face, so that the piston can be acted upon by the drive shaft. To reduce the danger of so-called seizing of the bearing faces moving back and forth on one another when poorly lubricating media such as fuel and in particular gasoline are being pumped, it is provided that a relief chamber, formed by a recess in the slide face disposed on the piston and open toward the slide bearing face on the stroke ring, communicates with the work chamber.

Abstract: A pump includes a main body, a piston slidably received in the main body, and a hose having a first end attached to an end of the main body and a second end attached to the piston. A handle is attached to a piston rod, which, in turn, is attached to the piston. Air is outputted to a main passage via the hose during an outward stroke. Air is outputted to the main passage via a hole defined in the end of the main body during an inward stroke.

Abstract: The present invention relates to a hydraulic brake system which operates by the feedback principle during brake slip control operations and includes a self-priming pump that aspirates pressure fluid from a pressure fluid reservoir for traction slip control operations. In order to improve the delivery rate of the pump, having a parallel arrangement of the two suction valves, a special construction of the pump-assembly is proposed, wherein the two suction valves are integrated in the pump housing. Advantageously, the suction valves are in axially opposed relationship, and the first suction valve is arranged on the movable piston, and the second suction valve is connected with a screw cap. Further, a pump for a slip-controlled hydraulic brake system according to the present invention is suggested having at least one suction valve with a valve seat, a closure member and a valve spring, the preload of the valve spring being variable in response to the position of a delivery piston.