Abstract: A diaphragm pump has at least one pump chamber, the pump chamber being connected to an inlet chamber via an inlet valve and to an outlet chamber via an outlet valve. The inlet valve has an inlet opening which can be closed by an inlet valve body, and the outlet valve has an outlet opening which can be closed by an outlet valve body. The outlet opening surrounds the inlet opening, or the inlet opening surrounds the outlet opening.

Abstract: In a sealed compressor (100) of the present invention, a valve plate (150) is provided with a plurality of discharge holes (151a, 151b) and a plurality of discharge valves (171a, 171b) which open and close the plurality of discharge holes. A tip end surface (160a) of a piston (160) is provided with a plurality of convex portions (161a, 161b), at least tip end portions of which are located inside of the discharge holes (151a, 151b) in a state in which the piston (160) is located at a top dead center.

Abstract: A manifold for a pump is configured to connect to a jacket to form a reservoir and to connect to at least one pumping mechanism disposed within the reservoir. The manifold includes a first side including a first side surface configured to face the reservoir and a second side including a second side surface. The manifold also includes a bypass passage, at least one push rod guide bore extending through the first side surface and the second side surface, and a leakage passage fluidly connecting the at least one push rod guide bore to an outlet disposed outside the first side surface. The manifold further includes a discharge passage including at least one inlet disposed in the first side surface, and the at least one inlet is configured to receive fluid pumped by the at least one pumping mechanism.

Abstract: A barrel assembly for a pumping mechanism includes a first end, a second end opposite the first end, and a plunger bore configured to receive a plunger for sliding within the plunger bore. The barrel assembly also includes at least one inlet passage including at least one inlet extending through the first end and fluidly connected to the plunger bore to communicate fluid from the at least one inlet passage to the plunger bore. The barrel assembly further includes an outlet passage fluidly connected to the plunger bore and configured to receive fluid from the plunger bore, the plunger bore and the outlet passage forming separate openings in the second end of the barrel assembly.

Abstract: A wobble piston is provided to be used in an air compressor for providing compressed air, and includes a piston cap having a generally flat first plate and a peripheral edge extending downwardly from the first plate. A connecting support rod is connected to the piston cap, and a compression ring is clamped between the edge of the piston cap and the support rod in complementary fashion. Upon assembly between the cap and the support rod, the compression ring has an angled side wall that is bent upwardly inwardly at a predetermined obtuse angle relative to a longitudinal axis of a cylinder.

Abstract: A hand pump includes a base having an inlet opening and an outlet opening, a manual pump disposed on the base and communicating with the inlet opening of the base, a receptacle disposed on the base and communicating with the outlet opening of the base, a casing disposed on the receptacle and having a passage coupled to the outlet opening of the base and having a channel coupled to the receptacle and having a pathway formed between the passage and the channel of the casing, and an outlet hole communicated with the channel of the casing, a valve shank is slidably engaged in the channel of the casing for selectively blocking and sealing the outlet hole of the casing.

Abstract: A pump has a pump barrel formed from a larger diameter section and a smaller diameter section. Each section has a biased piston moveable within the section and the pistons are connected together to form a variable volume chamber between the pistons. As the connected pistons move toward the larger diameter section, a volume of fluid is moved through an inlet valve into the variable volume chamber of increasing volume. When the pistons are moved toward the smaller diameter section, a differential volume of fluid is discharged from the variable volume chamber of decreasing volume through a discharge valve into a discharge conduit. The pistons are actuated to move within the pump barrel by application and release of pressure at a remote end of the discharge conduit.

Abstract: Disclosed is a hermetic compressor capable of preventing an intake valve from making contact with a piston without reducing compressing efficiency of the compressor. The hermetic compressor includes a cylinder block having a compressing chamber, a piston performing a reciprocation, a cylinder block coupled at an side of the cylinder block so as to close the compressing chamber and an intake valve plate which is provided between the cylinder block and the cylinder head and has an intake valve which controls a flow of a refrigerant introduced into the compressing chamber, wherein a compressing surface of the piston facing the intake valve plate forms a flat surface parallel to the intake valve plate and an anti-contact portion which receives a part of the intake valve is formed on the compressing surface so as to prevent the piston from making contact with the intake valve during the reciprocation of the piston.

Abstract: A manual negative pressure pump device comprises a suction cylinder, a handle, a pull, a piston, and an expandable spring which forms a vacuum absorbing device. A front end of the suction cylinder is a thread post with outer thread. The thread post has a central through hole and a plurality of small air holes around the through hole. The thread post is screwed with a nut of a joint. A valve and a drain-proof ring are installed between the joint and the thread post. The valve is a rubber washer and two ends of the washer have respective pins. The two pins are inserted into a central through hole of the joint and the central through hole of the thread post. The central through holes of the joint and the thread post are retained with a predetermined distance.

Abstract: The fuel injection system has a high-pressure pump which pumps fuel into a reservoir to be supplied to injectors disposed at the engine cylinders. A feed pump supplies fuel to the high-pressure pump. The high-pressure pump has at least one pump element including a pump piston that defines a work chamber and is driven in a reciprocating motion; the work chamber has a communication with the compression side of the feed pump, in which an intake valve opening toward the work chamber is disposed, and through which valve fuel flows into the work chamber upon the intake stroke of the pump piston. The intake valve has a valve member, which is urged in a closing direction by a closing spring, and the closing spring is braced at least indirectly on the pump piston; with an increasing intake stroke of the pump piston, the closing force exerted on the valve member by the closing spring becomes less. A minimal opening differential pressure of the intake valve is less than 0.9 bar.

Abstract: A pump (10) includes an impeller (12) positioned in a housing (11). A valve assembly (13) is positioned within a valve sleeve (25) which is carried by the impeller (12). The impeller (12) is carried by an armature (27), and a pocket (28) is formed between the impeller (12) and the armature (27) adjacent to the valve sleeve (25). One or more elastomeric members (29) are positioned in the pocket (28) to surround the impeller (12) at the area of the valve sleeve (25) to provide a retaining force on the valve sleeve (25).

Abstract: A magnet pump includes a synthetic resin casing, divided into a front casing and a rear casing and configured to internally form an impeller housing chamber and a magnet can housing chamber contiguous thereto, having an inlet and an outlet for a target fluid to be transferred. The casing forms an eddy chamber at a position for dividing the front casing and the rear casing along the outer rim of the impeller housing chamber to surround the outer rim of the impeller. The eddy chamber has overhangs formed at an entry of the eddy chamber hanging over from both sides in the rotational-axis direction of the impeller.

Abstract: A hydraulic pump unit for vehicle brake control system comprising a pump housing, a cylinder received in a receiving hole formed in the pump housing. The cylinder has a bottom portion and is provided at the bottom portion with an outlet valve. A plunger is slidingly received in the cylinder and defines a pump chamber in cooperation with the cylinder. An inlet valve provided on the plunger, an inlet passage formed in the pump housing. An opening of the inlet passage is provided in the receiving hole. An outlet passage formed in the pump housing, an opening of the outlet passage is provided in the receiving hole. A plug member for closing an opening of the receiving hole, the plug member is fixed to the bottom portion of the cylinder, and an orifice plate having a passage is arranged between the bottom portion and the plug member.

Abstract: A piston pump comprises cylinder attached within a cavity of a pump housing. An outlet check valve seat is defined about an outlet of the cylinder. A piston is slidably received in a bore of the cylinder and has a first passageway formed therein. A cylinder head encloses the outlet of the cylinder and defines a second passageway therein. The first passageway has an inlet in fluid communication with the cavity of the pump housing, and an outlet in fluid communication with a pumping chamber defined in the pump housing. A first spring retains the piston to the cylinder. A first check valve member is a ball retained near a valve seat formed in the first passageway of the piston by a disk spring, and allows fluid to flow only from the inlet to the outlet of the piston.

Abstract: A pump includes a cylinder, a piston assembly, a first nozzle, a valve, a controller, a ring and a second nozzle. The cylinder defines first and second chambers and first and second channels for communication between the chambers. The piston assembly is received in the first chamber. The first nozzle defines a channel. The valve is received in the first chamber. The controller defines an axial channel and a radial channel communicated with the axial channel, and is received in the second chamber and linked to the valve through the second channel. The controller is movable between a first position for allowing the valve to seal the second channel and a second position for driving the valve to open the second channel. The ring is mounted on the controller so as to divide the second chamber into a first portion for communication between the first channel and the channel of the first nozzle and a second portion for communication between the second channel and the radial channel of the controller.

Abstract: A lubricant supply apparatus for a reciprocating compressor is provided having a lubricant cylinder fixed to a compressing unit having a lubricant suction passage and oscillating with the compressing unit. A lubricant piston is slidably inserted into the lubricant cylinder for sucking and discharging lubricant by generating a pressure change inside the lubricant cylinder in coordinated oscillation with the compressing unit. A lubricant valve fixed to the compressing unit and having a lubricant suction valve opening in a suction process of the lubricant piston and a lubricant discharge valve opening in a discharge process of the lubricant piston are also provided. A valve cover covers the lubricant valve and is fixed to the compressing unit and includes a discharge port opening and shutting by the lubricant suction valve.

Abstract: The pump (5) has at least one cylinder (6) in which slides a piston (16) moved positively in the compression direction and elastically in the intake direction. A compression spring (26) is located between the shutter (21) of an intake valve (19) and the piston (16) to push the shutter (21) elastically into a closed position by exerting elastic force varying according to the position of the piston (16). The shutter (21) has a plate (28) cooperating with a seat (22) on the intake valve (19) and moveable parallel to the piston (16); and the compression spring (26) acts on the plate (28) to advance both opening and closing of the intake valve (19).

Abstract: A compressor piston has protrusions which extend upwardly into discharge ports to minimize clearance at the end of the compression stroke. The protrusions fit into circumferentially isolated discharge ports, and each of the ports are associated with reed valves. Preferably a cutout portion is formed into the piston head to allow clearance for movement of the suction valve. The suction valve is positioned on an inner face of a valve plate and the discharge reed valves are positioned on an outer face. The protrusions are preferably frustro-conical.

Abstract: A piston pump having a piston axially movable against the force of a spring within an operating chamber connected via check valves to an operating cylinder and a hydraulic medium supply. A section of the piston that extends into the operating chamber has a reduced diameter extension which extends from a shoulder of the piston that delimits the operating chamber. The extension includes a thickened free end having a sealing surface facing the shoulder. A valve disk is located and guided on the extension in a gap between the shoulder and sealing surface and is capable of axially reciprocating movements thereon. The valve disk is provided with openings which provide a passageway for hydraulic medium from the operating chamber to a second check valve. The openings are blocked when the valve disk abuts the sealing surface.

Abstract: To enable economical production of a piston for a piston pump, the piston is made from a tubular deformed part and a closure plug, which is press-fitted with a protrusion into the deformed part. The piston has the advantage that the piston can be made without metal cutting in the form of deformed parts, for instance by extrusion, and hence can be produced quickly and economically.

Abstract: A compressor piston has protrusions which extend upwardly into discharge ports to minimize clearance at the end of the compression stroke. The protrusions fit into circumferentially isolated discharge ports, and each of the ports are associated with reed valves. Preferably a cutout portion is formed into the piston head to allow clearance for movement of the suction valve. The suction valve is positioned on an inner face of a valve plate and the discharge reed valves are positioned on an outer face. The protrusions are preferably frustro-conical.

Abstract: Disclosed is a radial piston pump having a longitudinally movable pump piston in a cylinder chamber which communicates with a suction valve. A closing body of the suction valve is loaded by a valve closing spring in the direction of its valve seat affixed to the housing. The valve closing spring is supported on the pump piston. The radial piston pump is especially useful in fuel injection systems of internal combustion engines, particularly in common rail injection systems.

Abstract: Disclosed is a piston pump having a pump housing with a cylinder head comprised of a first plate and a second plate. The plates which rest against each other and are screwed to the pump housing, have a first conduit which carries low-pressure fuel and leads to a first check valve disposed between the two plates. The check valve communicates with a cylinder chamber of the radial piston pump. A second conduit carrying high-pressure fuel leads from this cylinder chamber to a second check valve, which is disposed between the first plate and the pump housing. Seals that are appropriate to the load, in fact low-pressure seals, are provided in the region of the cylinder head that is subjected to low pressure and high-pressure seals are provided in the region of the cylinder head that is subjected to high pressure.

Abstract: The pump (5) has at least one cylinder (6) in which slides a piston (16) moved positively in the compression direction and elastically in the intake direction. A compression spring (26) is located between the shutter (21) of an intake valve (19) and the piston (16) to push the shutter (21) elastically into a closed position by exerting elastic force varying according to the position of the piston (16). The shutter (21) has a plate (28) cooperating with a seat (22) on the intake valve (19) and movable parallel to the piston (16); and the compression spring (26) acts on the plate (28) to advance both opening and closing of the intake valve (19).

Abstract: An oil supply apparatus of a linear compressor including an oil feeder frame having an oil cylinder, an oil suction hole communicated with the oil cylinder and an oil discharge hole; an oil cover combined to the oil feeder frame to cover the oil cylinder and having an oil suction opening selectively communicated with the oil suction hole and an oil communication space selectively communicated with the oil cylinder and the oil discharge hole; an oil piston positioned between the oil feeder frame and the oil cover, being inserted in the oil cylinder and performing a slidable reciprocal movement to suck and discharge oil; and a single oil valve positioned between the oil cover and the piston. In the apparatus, only one oil valve is used to reduce the parts in number and facilitate the assembling of the valve, and does not contact other structure during its operation of the opening and closing so that a proper amount of oil can be constantly supplied.

Abstract: A manual air pump includes an outer cylinder having a chamber therein, a head provided to a second end of the outer cylinder and including an outlet passage communicated with the chamber for supplying air to an object to be inflated, and an inner cylinder reciprocatingly mounted in the outer cylinder and including a longitudinal hole. An outer piston is attached to an end of the inner cylinder to move therewith. The outer piston includes a passage that is intercommunicated between the longitudinal hole of the inner cylinder and the outlet passage of the head. A piston rod is reciprocatingly mounted in longitudinal hole of the inner cylinder. An inner piston is attached to a second end of the piston rod to move therewith. A handle is secured to a first end of the piston rod to move therewith. A switch member is rotatably mounted to the first end of the outer cylinder and around the first end of the inner cylinder.

Abstract: An electrically driven hermetic compressor comprises a hermetic casing, an electric motor unit encased in the casing, and a compression mechanism encased by the casing and drivingly connected to the electric motor unit through a crankshaft. The compression mechanism includes a cylinder, a piston reciprocatingly slidable in the cylinder, a valve plate having formed therein a suction port and a discharge port and providing valve seats around the ports, suction valve and a discharge valve cooperating with the suction and discharge ports. The cylinder, the piston and the valve plate cooperate to define a compression chamber. The compressor further has a passage system providing separate passages for a gas to be compressed and the gas after compression, and a motion converting mechanism for converting rotary motion of the crankshaft into linear reciprocating motion of the piston.

Abstract: A multiphase piston-type pumping system including a feed line (13) for the fluid to be pumped and a discharge line (19) for the pumped fluid, with at least one first variable-volume chamber (2) designed for pumping, the fluid, and with chamber being defined by a first cylinder head (3), a first cylinder (4), and a first piston (5), whereby piston (5) moves along the longitudinal axis of cylinder (4) in the cylinder (4). A first drive element (6) moves the piston (5) in the cylinder (4). The system also has a casing (23) surrounding at least the space swept by piston (5), with the space being opposite the first chamber (2) with respect to and with the piston (5), said easing (23) containing a gaseous fluid. The piston (5) has a recess (20) designed to receive a projection (10) integral with cylinder head (3), whereby these two elements produce a jet of fluid directed at a discharge port (15).

Abstract: An air compressor includes a suction space, a compression space and a discharge space that are aligned with one another. The compressor also includes one-way valves that function as a suction valve and a discharging valve. The open areas of the suction valve and the discharge valve are sufficiently enlarged since both valves are not formed in the same element. Therefore, both valves can permit a large amount of air flow. Further, the suction space serves as a crank space so that fresh air is always drawn into the crank space to cool the crank space.

Abstract: A swash plate compressor with single ended pistons improves piston stability by providing the ends of the pistons with open, conical rims, the outer surfaces of the which match, and thereby enlarge, the outer surface area of the pistons. The pistons therefore have increased sliding support within the cylinder bores, but without significant added mass. The pistons work in cooperation with matching conical protrusions on the discharge valve plate, which substantially fill the interior of the rims at piston full stroke. The piston compression ratio is therefore kept substantially the same.

Abstract: A wear shield attached to a piston in a piston type compressor cushioning impact and reducing friction between the piston and a valve which opens in a direction toward the piston. During some conditions of operation, without the wear shield, a piston can impact the opening valve, which opens interior of a cylinder which holds the piston. The wear shield installed between the piston and the opening valve reduces wear on the piston and on the valve, and also reduces operating noise.

Abstract: A reciprocating pump suitable for use in an implantable medication dosage device has a piston movable in a chamber connected to a medication reservoir, the chamber having an output closable by a check valve. The check valve includes a movable element which is acted upon by a biasing system to urge the moveable element in a direction to close the check valve. The moveable element has a sealing surface against which an end face of the piston presses with tight adjacency as the piston moves to an extreme position during its output stroke.

Abstract: A ring valve apparatus is designed for efficient transfer of liquids and gases and for attaining near-perfect vacuum state of gases. Intake means consist of a flexible ring valve and three ports encompassed by valve seats. Exhaust means include a rigid ring valve, three port openings encompassed by valve, and three cylinders containing spring-loaded plungers. The configuration of the piston head and structure of the valves make possible a complete exhaustion of gases from a cylinder, a feature required for attaining near-perfect vacuum in a chamber.

Abstract: A method of assembling a reciprocating compressor, in which a piston for partitioning a cylinder into a compression chamber and a suction chamber is telescoped in the cylinder, a closure end plate is secured at an open end of the cylinder, the end surface of the piston and the bottom surface of the end plate define opposing sides of the compression chamber, the piston is perforated by a suction port for communicating between the compression chamber and the suction chamber, and a suction valve sits on the piston for opening and closing the suction port, comprising the following steps; (1) manufacturing in advance a plurality of closure end plate, the i-th end plate having a bottom surface formed by a projection of different height h.sub.i ; (2) defining two reference positions of the piston and cylinder, respectively, for the i-th compressor and measuring the interval D.sub.i between the reference positions; (3) selecting an end plate which has a projection of such a height that D.sub.i -h.sub.