Abstract: It is an object of the invention to, even in the case where liquid containing a sedimenting material such as slurry is used, prevent sedimenting and aggregation from occurring in a pump. As means for attaining the object, a bellows 7 that is extendingly and contractingly deformable in the axial direction is placed in a pump body 1 with setting the axis B of the bellows vertical so as to be driven to perform extending and contracting deformation, and form a liquid chamber 9 inside the bellows 7. A suction port 18 and a discharge port 19 are formed in an inner bottom face 4a of the pump body 1 facing the liquid chamber 9. Liquid is sucked from the suction port 18 into the liquid chamber 9 by extension of the bellows 7, and the liquid in the liquid chamber 9 is discharged from the discharge port 19 by contraction of the bellows 7. The inner bottom face 4a is formed into a conical shape in which the face is downward inclined as moving toward the discharge port 19.

Abstract: A system is disclosed for pumping fluids at desired average flow rates by applying a predetermined force to a pump chamber and pulsing an outlet valve of the pump chamber to deliver a fluid therefrom. In some embodiments, pump chambers are provided within removable pumping cartridges that are constructed and configured to be coupled to a reusable pump drive component. In other embodiments, the pumping cartridges include multiple pump chambers, which pump chambers are operated so that a pump flow rate of one pump chamber is a predetermined fraction of the pump flow rate of another pump chamber within the pumping cartridge.

Abstract: A diaphragm pump with hydraulically powered diaphragm that is so chucked on a circulating rim between a pump lid and a pump housing in a predetermined radial chucking area and with a predetermined press-on force between the pump lid and the pump housing that the press-on force will be below a flow limit of the diaphragm material. At least one elastic part is provided additionally in the chucking area. That part is so designed that it will elastically compensate for any reductions occurring during the operation of the diaphragm pump in the press-on pressure in the chucking area of the diaphragm between the pump lid and the pump housing.

Abstract: In order to provide a diaphragm type fuel pump which is compact and assures a stable operation, a cavity is formed in a pump body at a position where the pump body is in contact with a fuel discharge chamber. The cavity is arranged between outer and inner parts of the pump body and perpendicularly extends to a diaphragm. The pump body has a return path communicating with a fuel intake chamber and the cavity via opposite ends thereof. A pressure regulating mechanism is housed in the cavity using a cap attached to the pump body, and is positioned inside an outer diameter of a pump chamber. This prevents the pressure regulating chamber from projecting out of the pump chamber contrary to a pressure regulating chamber of the related art, and makes the fuel pump compact. A valve seat is formed in the cap which is separate from the pump body. This facilitates machining of the valve seat.

Abstract: The invention provides a fluid apparatus in which two or more kinds of chemical liquids can be rapidly stirred and mixed in a pump to a uniform concentration. A barrier membrane such as a bellows or a diaphragm that is reciprocally moved in the axial direction is disposed in a pump body so as to form a liquid chamber between the barrier membrane and an inner wall of the pump body. A suction port and a discharge port are disposed in the inner wall of the pump body. Supply pipes for the two or more kinds of chemical liquids are pipe-connected to an inlet portion of the suction port so as to join together. An outlet portion of the suction port is disposed in a side face of a protruding forward end of a suction check valve which is fixed to protrude from the inner wall of the pump body into the liquid chamber, whereby the outlet portion is opened so as to eject the two or more kinds of chemical liquids toward a circumferential wall in the liquid chamber.

Abstract: A pump (10) includes a chamber (14) communicating with a fluid inlet (12) and a fluid outlet (13) above the centerline thereof to minimize dead air space where air bubbles might form. A connector (21) having a bend or elbow (26) is formed at the fluid inlet (12). Upon actuation of a solenoid (37), a plunger (39) carrying a diaphragm (42) is moved to draw fluid around the elbow (26), through a valve (19) positioned at the fluid inlet (12), through the chamber (14), and out of the pump (10) through a valve (30) positioned at the fluid outlet (13). The energy of the fluid which might otherwise create a water hammer effect is absorbed by the elbow (26) prior to reaching the pump (10).

Abstract: A controller for a photoresist dispense pump is described that actively monitors the operation of the pump and dynamically determines completion of the refill of the pump. In one embodiment, pressure measurements are made during the refill step. Changes in the pressure measurements are used to indicate completion of the refill. After refill is completed, the refill step is terminated and the operation cycle is continued.

Abstract: A dual diaphragm pump comprises a first chamber, a second chamber, a mechanical link, and a drive mechanism. The first chamber comprises a first cavity and a first diaphragm. The first chamber couples a pump inlet to a pump outlet. The second chamber comprises a second cavity and a second diaphragm. The second chamber couples the pump inlet to the pump outlet. The mechanical link couples the first diaphragm of the first chamber to the second diaphragm of the second chamber. The drive mechanism couples to the first diaphragm and the second diaphragm. In operation, the drive mechanism drives the first diaphragm causing first fluid within the first cavity to exit the pump outlet while causing second fluid to be drawn from the pump inlet into the second cavity. Further in operation, the mechanical link imparts an inlet pressure force from the second diaphragm to the first diaphragm.

Abstract: The invention relates to a diaphragm pump with a device for controlling the position of a diaphragm separating the conveying chamber from the displacement chamber. As a replacement of the mechanical control of the refilling process, a pressure sensor is arranged in the displacement chamber, which is connected with an evaluation unit designed for generating a refill signal, which is switched so it actuates a refill valve through an operative connection. Advantageously, a second sensor for detecting the piston travel is provided, whose signal is linked with the signal from the pressure sensor. The invention furthermore relates to a method for controlling the position of a diaphragm.

Abstract: A pump has a flexible liner which is expanded and contracted by application of positive and negative fluid pressure for receiving and discharging fluent material. The liner is received in a rigid shell which defines the maximum volume received. In discharging fluent material, a vacuum is applied to one side of the liner, while applying pressure to the other side so the liner is collapsed against the rigid shell. The liner is arranged so as to be the only part of the pump which contacts the fluent material, and is replaceable to effect rapid and easy cleaning of the pump. The liner has multiple pump cells which can expand and contract for moving fluent material through the pump cell. The pump cells can be sized and arranged so that by selection of particular pump cells which receive the fluent material, precise volumes can be metered by the pump.

Abstract: Three or more diaphragm pumps (12,14,16) are interconnected to sequentially receive an activation fluid from corresponding piston and cylinder pumps (18,20,22) synchronized by a control mechanism (24) which includes a distributor plate (42) with directive shallow slots (80,82,84) for conduiting activation fluid to a porting plate (44) and via openings (60,62,64) to the piston and cylinder pumps (18,20,22).

Abstract: It is an object of the invention to, even in the case where liquid containing a sedimenting material such as slurry is used, prevent sedimenting and aggregation from occurring in a pump. As means for attaining the object, a bellows 7 that is extendingly and contractingly deformable in the axial direction is placed in a pump body 1 with setting the axis B of the bellows vertical so as to be driven to perform extending and contracting deformation, and form a liquid chamber 9 inside the bellows 7. A suction port 18 and a discharge port 19 are formed in an inner bottom face 4a of the pump body 1 facing the liquid chamber 9. Liquid is sucked from the suction port 18 into the liquid chamber 9 by extension of the bellows 7, and the liquid in the liquid chamber 9 is discharged from the discharge port 19 by contraction of the bellows 7. The inner bottom face 4a is formed into a conical shape in which the face is downward inclined as moving toward the discharge port 19.

Abstract: The invention generally concerns a submersible well pumping system comprising an axially elongated housing having a diameter less than the bore hole of the well, a multi-chamber hydraulically driven diaphragm pump, suspended in the well. The pump is driven by a self-contained, closed hydraulic system, activated by an electric or hydraulic motor. The flow of working fluid into and out of the working fluid sub-chambers is controlled by a two state snap-acting valve, in turn controlled by a control valve which senses the differential pressure across the working diaphragm and generates a hydraulic signal to change the state of the two state snap acting valve, typically when either diaphragm reaches the top of the pumping stroke. Singly or in combination, reliable operation of the two state snap acting valve is assured by adding an energy storage device, hysteresis in the control valves and/or a two position latch on the main valve.

Abstract: A micropump including a chamber plate with connected pumping chambers for accepting small volumes of a fluid and a pumping structure. The pumping structure includes a flexible membrane, portions of which may be inflated into associated pumping chambers to pump the fluid out of the chamber or seal the chamber. A working fluid in cavities below the flexible membrane portions are used to inflate the membrane. The cavities may include a suspended heating element to enable a thermopneumatic pumping operation. The pumping chambers are shaped to closely correspond to the shape of the associated flexible membrane portion in its inflated state.

Abstract: A pneumatically-actuated reciprocating fluid pump and shuttle valve combination operates in an “air-assist” mode and a “non-air-assist” mode. In the non-air-assist mode, the shuttle valve is shifted by a blast of pressurized supply air from the pneumatic chamber in its pumping stroke as the flexible diaphragms and drive shaft reach the end of their pumping stroke. This blast of pressurized air used to shift the shuttle valve has the effect of reducing the air pressure in the pneumatic chamber immediately prior to the point in time that the drive shaft reaches the end of its stroke in order to provide a cushioning effect at the end of each pumping strokes cycle, in order to lessen the effect of the drive shaft and diaphragms abruptly reversing direction at full air pressure. In the air-assist mode, a secondary source of compressed air is utilized to shift the shuttle valve, rather than drawing pressurized air from the pneumatic chamber during its pumping stroke.

Abstract: The invention is a subsea pump that includes pumping elements, each pumping element including a pressure vessel with a first and a second chamber therein and a separating member disposed between the first and second chambers. The first and second chambers are hydraulically connected to receive and discharge a hydraulic fluid and a drilling fluid, respectively. The separating member moves within the pressure vessel in response to a pressure differential between the first and second chambers. A hydraulic power supply is arranged to pump the hydraulic fluid to the first chamber of each of the pumping elements. A valve assembly is hydraulically coupled to the first chambers of the plurality of pumping elements and to the hydraulic power supply. Volume measurement devices are arranged to measure volumes of each of the first chambers and the second chambers.

Abstract: A method is provided for regulating fluid pump pressures by detecting an elevation differential between a fluid flow control device and the distal end of a fluid line in communication with the fluid flow control device. A fluid flow control device, for instance a peritoneal dialysis device, is at a first height, a distal end of a fluid line is at a second height, and a valved outlet, when open, affords communication between the fluid flow control device and the distal end of the fluid line. The elevation differential is correlatable with a pressure measurable during a calibration procedure provided as a part of the methodology.

Abstract: In a system and method for emptying wetlines on a tanker truck, a pipe is secured to the tanker truck and extends from the wetlines to the top of the housing tank of the tanker truck. A pump is mounted in the pipe or a housing connected to the pipe. The pump is preferably driven by air flow from a compressor.

Abstract: Pump chambers are disclosed that include at least one spacer element therein to prevent any gas in the pump chamber from being pumped from the pump chamber during pumping. In some embodiments, the pump chambers are included in removable pumping cartridges that are constructed and configured for coupling with reusable pump drives. Some embodiments of pump chambers including spacer elements therein comprise a substantially rigid component forming a wall of the pump chamber with a flexible or movable membrane disposed on the wall to form the chamber. Spacer elements in such pump chambers are, in some embodiments, attached to a wall of the substantially rigid component so as to prevent the movable/flexible membrane from contacting the wall during pumping.

Abstract: Reusable pump drive systems are disclosed that utilize pressurized fluids for creating a force on a flexible or moveable surface of a pump chamber of a pumping cartridge. One such system includes a variable sized orifice valve included as part of a fluid supply system, which valve is able to selectively control a fluid pressure applied to the surface of a pump chamber. Other such systems include a switch valve, which is configured to select a first or second fluid supply source within the system for applying a desired pressure to the surface of a pump chamber.

Abstract: A method for airtight joining of two membranes. An airtight and complete bonding of the two membranes is achieved by first producing a curvature in one of the membranes, then placing the convexly curved side of a membrane onto the membrane to be joined to it in an airtight manner, next joining the two membranes until the edge areas of the membranes are in contact, and finally applying a pressing force that seals the edge areas of the membranes in an airtight manner.

Abstract: A diaphragm pump, in which a working fluid control valve (D) opens a working fluid make-up passage (B24) to prevent a diaphragm (C) from being damaged when an excessive discharge pressure acts on the diaphragm. The working fluid control valve (D) for opening and closing the working fluid make-up passage (B24) is provided with a valve disc formed to be capable of reciprocating relative to the diaphragm (C) in a valve disc receiving chamber (B2) to close an opening of the valve disc receiving chamber (B2), means for biasing the valve disc toward the diaphragm, and means for closing the working fluid make-up passage (B24) when a distance, over which the valve disc extends from the opening of the valve disc receiving chamber, exceeds a predetermined value.

Abstract: A dual diaphragm pump includes a central housing having a pair of opposed housing surfaces, each surface having a housing diaphragm recess and a pair of housing valve recesses, and a pair of covers, each cover having a surface with a cover diaphragm recess and a pair of cover valve recesses. The covers are mated to the housing so that the diaphragm recesses form a pair of pumping chambers with diaphragms therein, and the valve recesses form valve chambers with check valves therein.

Abstract: A diaphragm pump prevents deformation, breakage, and the like of a diaphragm caused by the diaphragm being pushed strongly against a discharge opening during operation of the diaphragm pump, and that also provides smooth fluid transfer of the pumped fluid. At its extreme discharge position, the diaphragm is blocked from entering the pumped fluid discharge opening by a perforated diaphragm protecting device covering the fluid discharge opening. Selection of the size of openings in the diaphragm protecting device, appropriate for the materials being pumped, allows smooth movement of pumped fluid in the pump through the pumped fluid discharge opening, without interference. In one embodiment, the diaphragm protecting device is a movable perforated plate which is resiliently urged open, and which is pushed closed when the diaphragm reaches its discharge extreme position.

Abstract: A diaphragm pump with a pump lid, a pump housing and a hydraulically powered diaphragm that is arranged between the former, that delimits a hydraulic chamber from a delivery chamber and that is clamped in a circulating rim. There is provided between the pump lid and the pump housing an insert part, which is located on the side of the pump lid and which limits the delivery chamber and/or an insert part that is located on the side of the pump housing and that delimits the hydraulic chamber, while the diaphragm at its circulating rim is clamped between the insert part and the pump housing or the pump lid or between insert parts.

Abstract: A pulsation type diaphragm pump prevents back flow of a fuel and has reduced parts and assembly requirements. An intake valve disposed between an intake chamber and a pump chamber has an intake valve seat protruded to an inner portion of the pump chamber and an intake valve body formed by a portion of a pump diaphragm. The intake valve body opens and closes an intake valve seat port in cooperation with an intake seat surface in accordance with oscillation of the pump diaphragm. A discharge valve disposed between the pump chamber and a discharge chamber has a discharge valve seat protruded to an inner portion of the discharge chamber and a discharge valve body formed by a portion of a pulsator diaphragm. The discharge valve body opens and closes a discharge valve seat port in cooperation with a discharge seat surface in accordance with oscillation of the pulsator diaphragm.

Abstract: The present invention relates to a micropump which is driven by movement of a liquid drop based upon continuous electrowetting actuation. The continuous electrowetting means a phenomenon that the liquid drop moves as the surface tension of the liquid drop is electrically varied in succession. When a tube in which electrolyte and a liquid metal drop are inserted is applied with voltage having periodically changing polarity via metal electrodes, the surface tension of the liquid metal is varied so that the liquid metal drop reciprocates in the tube generating pressure or force, which is used as a driving force of the micropump. The micropump is operated in a low voltage and consumes a small amount of electric power.

Abstract: An air driven double diaphragm pump has two opposed pumping cavities with diaphragms extending thereacross. A shaft extends between the diaphragms and through an actuator housing. The housing includes a control valve assembly having a control valve to direct pressurized air to one or the other of the dual pumping cavities and two relief valves which cooperate with the pump shaft position to release air from one end or the other of the control valve for the shifting thereof. Shuttle valve elements are positioned between the control valve and the pumping chambers. The shuttle valve elements are slidably positioned within the valve cavities to move between extreme positions under the pressures within the input and the pumping cavity. In one extreme position, the pumping cavity is in communication with an exhaust having a tapered passage. In the other, the exhaust is cut off and pressurized air is able to pass through a one-way valve in a passageway through the shuttle valve element to charge the pumping chamber.

Abstract: A diaphragm pump comprising a first diaphragm operated with a driving mechanism such as a crank mechanism, a second diaphragm disposed so as to form an air chamber between the first diaphragm and the second diaphragm, and a pump chamber formed by the second diaphragm and a casing or the like, wherein the a pressure in the air chamber is changed by operating the first diaphragm with the driving mechanism and the second diaphragm is deformed by a change of the pressure in the air chamber to perform a pump function.

Abstract: An object of the present invention is to provide a restarting device of a pump change-over valve for restarting an operation of a pump automatically by using a driving fluid in such an event that the operation of the pump is shut down due to a change-over valve stopping in a neutral position, which valve is to be moved forth and back in order to switch the operation of the pump.

Abstract: A valve arrangement including a valve housing (10) which includes an inlet port (11) and two outlet ports (12, 13) for fluid flowing through the housing. A valve element (15) is accommodated in a first valve space in the valve housing and movable between two end positions. The valve element includes two surfaces (16), each of which is adapted for co-action with a respective outlet port such as to close an associated outlet port in one and the other of the end positions of the valve element (15). A device (20 or 21 and 26, 47) for resetting the valve element between the positions. The valve element (15) is mounted on one end of a pivotal arm (18) and has the form of a valve plate or disc which includes valve-element surfaces (16) for alternate co-action with a respective outlet port (12, 13).

Abstract: A fluid dispensing system is provided which has a first diaphragm pump, a filter connected to receive the discharge of said first pump, and an accumulator/second diaphragm pump connected to receive the discharge of said filter. Hydraulic fluids pumped by cylinder/piston/stepper assemblies independently actuate each of the diaphragm pumps, providing accurate, controllable and repeatable dispense of the subject fluid. There is also structure operable to suck back fluid from downstream of the second pump.

Abstract: A valve housing (10) includes an inlet port (11) and two outlet ports (12, 13) for fluid passing through the housing. A valve element (15) accommodated in the valve housing is moveable freely between two end positions and has two surfaces (16) each adapted to close a respective outlet port in one and the other of the two end positions of the valve element. The valve element further includes members (20, 22: 21, 22: 21, 26, 47; 26, 48; 26, 50; 26, 51-54) for resetting between the positions. A double-action pump includes two spaces or rooms that have valve-controlled inlets and outlets (39, 40; 29, 30) for drive fluid and pump-transported working fluid respectively. The spaces are divided into an operating chamber (28) and a working chamber (27) by partition walls (26, 36, 37) which are pistons or diaphragms (26) and reciprocatingly move between end positions.

Abstract: A positive displacement liquid-delivery apparatus includes a positive displacement pump 110 and a differential pressure control unit 142. The positive displacement pump 110 includes a liquid-delivery chamber 128 having a watertight housing 122 with one part formed of a flexible diaphragm 124, and a diaphragm driver 136 linked to the diaphragm 124 for deforming the same to discharge fluid from the liquid-delivery chamber 128. The differential pressure control unit 142 uniformly controls the differential pressure inside and outside the diaphragm 124 during the pumping process.

Abstract: Pumping cartridges are disclosed for use in pumping systems. One such cartridge includes a series of fluid flow paths therein and a bypass valve therein, the bypass valve can selectively block fluid flow along one or both of two fluid flow paths through the valve. In some embodiments, the pumping cartridges are removable from a reusable pump drive component. In some embodiments the pumping cartridges comprise a substantially rigid component having one or more channels and/or depressions therein covered by a membrane so that together the rigid component and the membrane define a series of fluid flow paths, pump chambers and fluidic valves, including a bypass valve.

Abstract: The invention provides a system for dispensing fluid at relatively constant pressure. In a first embodiment, the invention dispenses a fluid from a chamber of varying dimension defined by a pre-tensioned resilient membrane. In a second embodiment, the invention dispenses a fluid from a chamber defined by a dispensing membrane, which is substantially surrounded by another fluid contained within a pressure chamber of varying dimension defined by a pre-tensioned resilient membrane. In a third embodiment, the invention dispenses multiple fluids, a first fluid from a first dispensing chamber of varying dimension defined by a pre-tensioned resilient membrane, and a second fluid from a dispensing chamber of varying dimension defined by a dispensing membrane substantially surrounded by the first fluid.

Abstract: A pump for ultra-pure fluids comprises a flexible diaphragm separating a fluid chamber from an air chamber. The diaphragm creates an airtight seal between the fluid chamber and the air chamber when a self-centering and trapezoidal shaped wedge compressively forces the diaphragm into a trapezoidal shaped perimeter cavity surrounding the chambers. Any leak from the fluid chamber into the air chamber is detected by a fiber optic system comprising two optical fibers that are disposed at an angle that is calculated to enable light to pass between the fibers only in the presence of a liquid having a predetermined index of refraction. The fiber optic system can also be used to determine the stroke of the pump by disposing the fiber optic lines at an angle calculated to reflect light off of the oscillating diaphragm when the diaphragm arrives at a predetermined location.

Abstract: A reversing valve for a compressed air membrane pump in which an equilibrium state of the main piston in the neutral position, leading to stoppage of the pump, is prevented by disposing the main system piston and the pilot system piston immediately adjacent to one another.

Abstract: Method and apparatus for optimizing the oil flow inside of a diaphragm compressor concerns the previously non-organized oil flow in the head of a diaphragm compressor leading to the previous formation of pockets between the diaphragm and the cover curve, the method and apparatus providing a continuous circulation of oil in the pressure stroke and in the suction stroke which is achieved by means of a valve plate which in the pressure stroke of the piston closes holes in the middle area of the aperture plate automatically and in the suction stroke of the piston again frees those holes automatically.

Abstract: The invention relates to a system for the circulatory conveyance of media, with a drive and with two conveying chambers, the first conveying chamber constituting a feed chamber and the second conveying chamber a return chamber.

Abstract: A vibrating membrane fluid circulator comprising an internal hydraulic circuit made up in succession of an admission orifice (1), a pump body (2), and a delivery orifice (3), the pump body (2) defining, in operation, a space (4, 18, 30) having rigid walls (5, 6) between which a deformable membrane (9) is placed having means for coupling its end (11) adjacent to the admission orifice to a motor member (39) generating a periodic excitation force substantially normally to the surface thereof, said membrane (9) being associated with means for creating tension parallel to the fluid circulation direction, said membrane constituting the medium for waves travelling from the end subjected to the excitation force towards its opposite end situated adjacent to the delivery orifice, said displacement being accompanied by forced damping due to the shape of the rigid walls so as to transfer energy from the membrane to the fluid giving rise to a pressure gradient and to fluid flow related to the dimensions of the pump body a

Abstract: The present invention is directed to a multiport metering pump that can completely deliver a very small volume of liquid. The multiport metering pump includes a number of ports (or valve units), each of which can be used as either an outlet valve or an inlet valve. The multiport metering pump includes: a central gallery; a displacement unit; multiple valve units; and multiple conduits that respectively connect the displacement unit and the valve units to the central gallery. The displacement unit and the valve units communicate with the central gallery, and any of the valve units can be used as an inlet valve or outlet valve for the liquid delivery.

Abstract: A pump for ultra-pure fluids comprises a flexible diaphragm separating a fluid chamber from an air chamber. The diaphragm creates an airtight seal between the fluid chamber and the air chamber when a self-centering and trapezoidal shaped wedge compressively forces the diaphragm into a trapezoidal shaped perimeter cavity surrounding the chambers. Any leak from the fluid chamber into the air chamber is detected by a fiber optic system comprising two optical fibers that are disposed at an angle that is calculated to enable light to pass between the fibers only in the presence of a liquid having a predetermined index of refraction. The fiber optic system can also be used to determine the stroke of the pump by disposing the fiber optic lines at an angle calculated to reflect light off of the oscillating diaphragm when the diaphragm arrives at a predetermined location.

Abstract: A mechanical fuel pump includes first and second flexible members disposed within a pump body. The first flexible member is deflected in timed sequence with a rotating engine member. Deflection of the second flexible member is limited to select the amount of fuel expelled from the pump for each engine cycle. A stop member is movable in response to movement of an engine governor and throttle to result in increased fuel and air being supplied when the engine encounters a load.

Abstract: A pump, for moving a pumped fluid using a pumping fluid, comprising an outer housing defining an interior volume. A compressible main tube, having an interior space, is located within the outer housing. Inlet and exit valves, both having internal check valves, are in communication with the interior space of the compressible main tube. The outer housing is selectively filled with pressurized pumping fluid through a drive intake to compress the main tube and force pumped fluid contained therein out through the exit valve. The pressurized pumping fluid is then released through a bleeder valve to relieve pressure upon the main tube, allowing it to expand, and causing it to draw pumped fluid into its interior space through the inlet valve. Reiteration of these steps is controlled by a solenoid valve which selectively allows or prevents flow of the pumping fluid through the drive intake into the internal volume of the outer housing.

Abstract: A diaphragm 46 is sandwiched between a first body 16 and a second body 18, and comprises an outer diaphragm 50 which is made of synthetic resin and has an opening 48 formed within an effective diameter X, and an inner diaphragm 52 arranged in the opening 48. The outer and inner diaphragms 50 and 52 are hermetically sealed by a coupling member 54 made of rubber. Therefore, the diaphragm 46 reciprocates as a synthetic resin diaphragm at very low temperatures. At normal temperatures, the inner diaphragm 52 reciprocates extensively via the rubber coupling member 54 compared with the outer diaphragm 50, thereby increasing a flow rate of the fuel pump compared with a fuel pump in which a diaphragm is made only of synthetic resin. When the diaphragm 46 is replaced depending upon a desired flow rate, the second body 18 can be manufactured using one die, which is effective in reducing manufacturing costs.

Abstract: A dual diaphragm pump comprises a first chamber, a second chamber, a mechanical link, and a drive mechanism. The first chamber comprises a first cavity and a first diaphragm. The first chamber couples a pump inlet to a pump outlet. The second chamber comprises a second cavity and a second diaphragm. The second chamber couples the pump inlet to the pump outlet. The mechanical link couples the first diaphragm of the first chamber to the second diaphragm of the second chamber. The drive mechanism couples to the first diaphragm and the second diaphragm. In operation, the drive mechanism drives the first diaphragm causing first fluid within the first cavity to exit the pump outlet while causing second fluid to be drawn from the pump inlet into the second cavity. Further in operation, the mechanical link imparts an inlet pressure force from the second diaphragm to the first diaphragm.

Abstract: A diaphragm pump with hydraulically powered diaphragm that is so chucked on a circulating rim between a pump lid and a pump housing in a predetermined radial chucking area and with a predetermined press-on force between the pump lid and the pump housing that the press-on force will be below a flow limit of the diaphragm material. At least one elastic part is provided additionally in the chucking area. That part is so designed that it will elastically compensate for any reductions occurring during the operation of the diaphragm pump in the press-on pressure in the chucking area of the diaphragm between the pump lid and the pump housing.

Abstract: A diaphragm pump with a pump lid, a pump housing and a hydraulically powered diaphragm that is arranged between the former, that delimits a hydraulic chamber from a delivery chamber and that is clamped in a circulating rim. There is provided between the pump lid and the pump housing an insert part, which is located on the side of the pump lid and which limits the delivery chamber and/or an insert part that is located on the side of the pump housing and that delimits the hydraulic chamber, while the diaphragm at its circulating rim is clamped between the insert part and the pump housing or the pump lid or between insert parts.

Abstract: A double diaphragm pump having an air chamber housing centrally located between two pump chamber housings. The air chamber housing includes a center section and two outwardly facing concave discs. Each pump chamber housing includes a pump chamber shell mating with one of the discs with a flexible diaphragm therebetween. Check valve chambers and inlet and outlet passages associated with each pump chamber and with inlet and exhaust manifolds control flow through the pump. A solenoid actuated valve alternately directs air pressure to each of the two diaphragms for reciprocal pumping action. Inner pistons associated with the diaphragms include stops which limit pump stroke in each direction. The solenoid may be driven by conventional electronics on a timed stroke or responsive to flow considerations.