Abstract: A piston pump includes a pump housing having a suction port, a discharge port, and an internal cavity; a first cylinder member having a cylinder bore; a piston built into the cylinder bore of the first cylinder member to thereby form a pump chamber and adapted to change the volume of the pump chamber by means of axially reciprocating movement; a suction valve provided in the piston; and a discharge valve provided at the discharge side of the pump chamber. A circumferential protrusion is formed externally at an axially intermediate portion of the first cylinder member. The first cylinder member is press-fitted, at the circumferential protrusion, into the internal cavity of the pump housing. A leading end portion of the first cylinder member from which the first cylinder member is inserted into the pump housing has a diameter smaller than that of the internal cavity of the pump housing.

Abstract: A mini pump comprises a body includes a head, a handhold portion extending from the head and a groove, a nozzle device having a cover element, a nozzle and an anti-sliding element, with the anti-sliding element disposed on the head and partially received in the groove. The cover element engages the anti-sliding element to cylinder and prevents the nozzle from coming off the body. The handhold portion and the anti-sliding element are respectively made of resin with different hardness. The material of the handhold portion of the body is tougher than that of the anti-sliding element of the nozzle device.

Abstract: A metering pump device for a vehicle heater includes an inlet chamber, an outlet chamber, a first valve arrangement between the inlet chamber and the outlet chamber, which permits a fluid exchange substantially only from the inlet chamber to the outlet chamber, a displacement piston element, which in a first piston position minimizes the volume of the inlet chamber and in a second piston position minimizes the volume of the outlet chamber.

Abstract: A pump system for delivering cryogenic liquids is proposed that is suitable, for example, for refueling motor vehicles with H2. It consists of a container for receiving the cryogenic liquid, in which at least one pump is arranged that is designed as a reciprocating pump with connecting rod actuation and spring recover. Pump cylinder (10) of the reciprocating pump is divided by means of plunger (24, 37) into two chambers (a and b) that are arranged on the pressure side or the induction side. By exerting tensile forces on connecting rod (29), in the pressure stroke the cryogenic liquid that is located in the container is initially trapped in chamber (b). When connecting rod (29) is returned to its starting position by return spring (23), the liquid that is trapped in chamber (b) is then hurled without pressure into chamber (a). In the subsequent pressure stroke, the liquid is finally released via a gap (d) to a pressure housing and from there to the consumer by exerting tensile forces on connecting rod (29).

Abstract: A medium and high pressure pump systems supplies a cryogenic fluid from a storage tank and methods of operating such systems to remove both liquid and vapor from the storage tank to reduce the need for venting. The system comprises a pump that is operable to pump cryogenic liquid or a mixture of cryogenic liquid and vapor. In accordance with the method, mass flow rate through the pump is controlled by selecting one of at least two operating modes. In a first operating mode a high flow rate is achieved by supplying cryogenic liquid to the pump from the storage tank to substantially fill a compression chamber within the pump with liquid. In a second operating mode, a lower mass flow rate is achieved by selectively simultaneously supplying liquid and vapor from the storage tank to the pump, with the vapor fraction being higher in the second operating mode compared to the first operating mode.

Abstract: A vehicle fuel system has an integrated fuel rail and fuel pump that supplies high pressure fuel directly to the injectors mounted on the engine. The pump is a double acting single piston pump that has two pumping chambers formed co-axially in a single cavity. One pumping chamber is twice the size of the other pumping chamber thereby producing an output flow equal to one half the volume of the larger pumping chamber during each stroke. The smaller pumping chamber communicates with a co-axial fuel rail portion of the cavity. A plurality of outlet ports, one for each injector, are disposed in fluid communication with the fuel rail portion of the cavity.

Abstract: A hollow through-bolt is threaded internally and externally, at one end, to receive therein a reciprocable, end-threaded rod. A pair of fluid-control valves, centrally bored, are mounted on the through-bolt in spaced apart disposition. The other end of the through-bolt has a shoulder formed thereon for seating one of the valves thereagainst, and the other valve central bore is tapped for threaded engagement with the one end of the through-bolt. A sleeve, slidably engaged with the through-bolt, and interposed between the valves, maintains the one valve positioned against the shoulder.

Abstract: An object of the present invention is to provide a pump which suppresses a decrease in the volumetric efficiency of the pump to a great extent even in case that the kinematic viscosity of a fluid is high with a compact structure of the pump itself.

Abstract: A swash plate compressor is disclosed having double acting pistons that reciprocate in aligned sets of horizontally extending bores of a cylinder block to compress gaseous refrigerant. An improved asymmetrical arrangement of suction or intake ports is provided in at least the bottommost piston. The ports extend longitudinally through the operating heads of the piston and are connected by an open channel so as to provide fluid communication through the piston. A matching valve disc with a flexible ring is included so as to provide unidirectional flow through the suction ports during the intake stroke. The suction ports are on a constant radius arc spaced 30.degree. apart and are excluded from the lower 120.degree. portion of the piston to form the asymmetrical arrangement. Liquid lubricant in the reservoir pool adjacent the bottom of the crankcase is sufficiently spaced from the ports so that it is prevented from being drawn through the suction ports and into the cylinder bore, thus eliminating slugging.

Abstract: The compressor is formed of a simple, straight cylinder clamped between end headers by means of tie bolts. Confined within the cylinder are inlet valves--one at each end thereof--and inlet ports formed in the cylinder open onto these valves. A reciprocable piston rod carries a pair of spaced-apart discharge valves thereon. The latter valves, having annular bodies, have piston ring grooves formed thereabout, to receive sealing piston rings therein; too the discharge valves serve as the gas compressing pistons.

Abstract: A nozzle with self-contained high pressure booster pump is carried on a pistol grip handle with a small motor to drive the eccentrically-pump. A portion of the water from a conventional hose fitting flows laterally into a pump cylinder and then radially through the piston itself to exit axially through a check valve and into the pump chamber ahead of the piston. During the working stroke the water is driven out of the piston into a pressure chamber and then through a restricted passageway to exit in a jet stream. Another portion of the supply water is diverted around the pump cylinder to the same nozzle to flush away debris loosened by the jet stream.

Abstract: A completely dry fluid-tight reciprocating vacuum pump comprises one or more pumping chambers defined between two rigid parts which face one another in the axial direction. One is reciprocated in a straight line relative to the other. They are connected to one another by at least one axially flexible member of appropriate radial stiffness. Each of these members comprises an outside part fixed to a first of these rigid parts. The side of the first rigid part facing the flexible member is shaped to have a profile in diametral cross-section which is substantially the same as the profile in diametral cross-section that this member tends to assume, by virtue of its stiffness, in the configuration with the aforementioned rigid parts moved towards one another. The pump can be used for pumping corrosive and radioactive gases, such as tritium, for example.

Abstract: A piston vacuum pump includes a housing (40) which is extruded from aluminum to form a bore (42) for movably receiving a piston (44). The piston is made from a plastic material to define a sealing interface with the aluminum housing in the absence of additional sealing rings and lubricants. The extruded housing is also provided with an opening (64) to receive an input member (90) and to provide for fluid communication through the pump.

Abstract: A pump having a body including at least two axially aligned pumping chambers each of which contains an actuator having a main central rigid portion and a peripheral sealing ring retained in a clearance space and under radial compression in non-sliding fluid-tight relation between the main central portion and a lateral wall of the pumping chamber, such main central portions of the actuators being joined by a rigid connecting rod having further sealing rings embracing it and engaged with the side walls of respective pumping chambers to form a resiliently supported unit which is reciprocable axially of the pumping chambers and is driven by provision of contact faces on the connecting member spaced apart along said axis and facing in opposite directions, and between which is received the outer race of an anti-friction bearing carried on an eccentric of a drive spindle mounted for rotation in the pump body at right angles to the pumping chamber axis.

Abstract: A compressor utilizing opposing cylinders and flap valves in which the configuration may be readily modified from compressor to vacuum operation by simple reversal of components. Convertibility is facilitated by a valve plate having apertures which connect opposed cylinders and a manifold channel to opposed end chambers. Reversible flap valves are mounted on the valve plates and on the pistons. Additionally, a Scotch-yoke type mechanism of novel construction is provided in which the slider is formed of porous bronze and in which lubricant-containing wick material is disposed in the slider normal to and within the crankpin bearing hole.