Abstract: An electromagnetic actuator for a microfluidic pump of the type that causes periodic pinching and releasing against the walls of a fluidic channel, e.g., a tube. At least one permanent magnet is placed against the walls of the fluidic channel, and located in an area with magnetic fields, produced by coils that are radially symmetric to the channel. The permanent magnet is cause to press and release against the wall of the fluid channel to cause a fluid flow through the channel.

Abstract: In a chemical liquid supplying apparatus, discharge accuracy of chemical liquid is enhanced, and durability of a flexible tube is enhanced. By the flexible tube incorporated into a pump housing, an interior of the pump housing is partitioned into a pump chamber, which communicates with a liquid inlet and a liquid outlet, and a drive chamber in which an incompressible, indirect medium is enclosed. Outer surfaces of end portions of the flexible tube are sealed by outer seal members, and their inner surfaces are sealed by inner seal members. Fastening cylindrical bodies disposed in the end portions of the flexible tube are radially expanded by wedge sleeves, whereby the outer and inner seal members are caused to closely contact with the flexible tube.

Abstract: The present invention relates to positive displacement pumps, and particularly to diaphragm positive displacement pumps. An inventive diaphragm positive displacement pump is provided comprising at least one pumping chamber containing a deformable hose diaphragm, a working fluid cylinder fluidly connected to the deformable hose diaphragm, and at least one linear motor to displace the working fluid within the working fluid cylinder and thereby increase and decrease the volume of the pumping chamber. An inventive method of controlling an inventive diaphragm positive displacement pump comprising at least one pumping chamber and powered by at least one linear motor is also provided.

Abstract: An infusion pump includes an actuator having an output shaft; a pump actuator having a length (lactuator) moved by the output shaft and in contact with tubing, such that the pump actuator at an output shaft actuated distance (x) creates flat contact areas with the tubing, and wherein remaining non-contact areas of the tubing are at least substantially circular in shape; and a logic implementer configured to use at least two relationships to solve for a same number of variables to calculate a cross-sectional area of the tubing at an output shaft actuated distance (x).

Abstract: An aerating bag has a body, a connector, a check valve and an intake valve. The body has a connecting tube, a mounting tube and a chamber. The chamber communicates with the connecting tube and the mounting tube. The connector is detachably connected to the body and has a connecting pipe, an inserting pipe, a mounting recess, a release pipe and a cover. The release pipe is formed on and protrudes from the connector and communicates with the connecting pipe and the inserting pipe. The cover is mounted on the release pipe. The check valve mounted in the mounting recess and has an open end, a closed end and a slit. The slit is formed longitudinally in the check valve near the closed end and communicates with a clearance between the connecting pipe and the check valve. The intake valve is detachably mounted in the mounting tube of the body.

Abstract: A chemical liquid supplying apparatus 10 has a bellows 11, which includes a small-size bellows portion 13, a large-size bellows portion 14 with a larger volume change per axial-directional unit displacement amount than that of the small-size bellows portion 13, and a drive portion 12 therebetween. An apparatus main body 10a to which the bellows 11 is attached includes a supporting member 21 to which a fixed end portion 15 of the bellows 11 is attached and a supporting member 22 to which a fixed end portion 16 of the bellows 11 is attached. A drive sleeve 27 surrounds the bellows 11 and is rotatably supported on the apparatus main body 10a. A driven cylinder body 32 attached to the drive portion 12 converts rotation of the drive sleeve 27 to axial-directional movement of the drive portion 12.

Abstract: The invention provides a finger-type peristaltic pump (2) having a body (4) and a housing (6). The body contains two or more finger-type valves (16) and a processor (22) configured to operate the valves according to a predetermined temporo-spatial pattern. The housing has a passageway (18) configured to receive a conduit. The housing has a first position in which a conduit in the passageway is positioned adjacent to the valve fingers, and a second position in which a conduit in the passageway is not adjacent to the valve fingers. The invention also provides a housing for use in the pump of the invention.

Abstract: The invention provides a priming pump comprising a deformable envelope associated with an inlet endpiece and an outlet endpiece each fitted with a moving valve member, the endpieces being arranged in such a manner that when the valve members are in the closed position, the outlet endpiece presents a leakage rate that is greater than the leakage rate of the inlet endpiece.

Abstract: A microdosing apparatus and method include a fluid conduit having a flexible tube with a first end for connecting to a fluid reservoir and a second end where an outlet opening is located. An actuating device with a displacer with an adjustable stroke is provided, by which the volume of a portion of the flexible tube can be changed to thereby dispense liquid as free flying droplets or as a free flying jet at the outlet opening by moving the displacer between a first end position and a second end position, whereby the tube is partly compressed in the first or the second end position.

Abstract: A hand operated fluid dispensers comprised of a sealed flexible reservoir chamber containing a fluid, a flexible pump chamber encased by and drawing fluid from the reservoir, and a pump cycled by external pressure applied through a reservoir wall. This class of simple, inexpensive, disposable dispensers is particularly useful in packaging cosmetics, foodstuffs, and healthcare products. As pocketable dispensers they are popular for dispensing small amounts of stored viscous liquids easily damaged when exposure to the atmosphere, a condition where sealed reservoirs coupled with airless pumps working together successfully prevent such product contamination and deterioration. A method of improved healthcare employing such pump dispensers containing a hand sanitizing fluid is also discussed.

Abstract: A pump is provided having a disposable bladder and disposable conduits together with check valves that control fluid flow through the bladder and conduits when the bladder is alternately compressed and expanded. The use of disposable conduits and bladder eliminates the need for hygienically regenerating the pump between uses. The pump can be utilized in a fluid delivery system such as tangential flow filtration.

Abstract: The present invention relates to a method for the preparation of a treatment machine for the treatment of a medical liquid comprising a coupling surface with actuators, with a cassette comprising a hard part with liquid-conducting passages which are covered by a flexible film being able to be coupled to the coupling surface of the treatment machine so that the actuators can control the liquid flow in the liquid-conducting passages by pressing the flexible film down into the cassette. In this connection, a switch is made after the setting up of the treatment machine and before the start of treatment into a stand-by mode in which the actuators are alternately moved to relieve the flexible film. It is possible for the first time by the stand-by mode before the start of treatment in accordance with the invention to completely uncouple the time-consuming setting up of the treatment machine from the treatment itself in a time aspect.

Abstract: A pumping system and related methods involving an outer chamber and an inner chamber extending between two endplates, wherein the circumference of the inner chamber may be adjusted via a plurality of ribs and linear motors.

Abstract: The invention provides a priming pump comprising a deformable envelope associated with an inlet endpiece and an outlet endpiece each fitted with a moving valve member, the endpieces being arranged in such a manner that when the valve members are in the closed position, the outlet endpiece presents a leakage rate that is greater than the leakage rate of the inlet endpiece.

Abstract: A diaphragm circulator for liquid material having an internal circuit provided with at least one material intake orifice for discharging the material. The circulator body defines a propulsion chamber with rigid walls between which a deformable diaphragm is placed in such a way that the edge thereof is adjacent to the intake oriface and the edge is adjacent to the discharge orifice for forming a ripple carrier. A diaphragm-exciting member is arranged on the side of the intake orifice for producing a reciprocating motion on the corresponding diaphragm edge in such a way that the ripple is generated and is provided with the circulator rigid walls which are arranged inside free ripple amplitude envelope surfaces extending along the diaphragm.

Abstract: The invention provides a pump, in particular for a chemically reactive fluid, in which a pump head comprises at least two walls between which there is defined a pump chamber for pumping the fluid in question, one of the walls being stationary, the other wall being movable or deformable relative to the stationary wall by means of a drive or deformation device, at least the stationary wall being provided with a protective coating against the fluid, wherein the coating is constituted by a sheet of plastics material applied in leaktight manner against the wall at the periphery thereof, with the space between the protected surface and the coating sheet, within the zone where they make leaktight contact, being filled with an incompressible liquid.

Abstract: A chemical liquid supplying apparatus can discharge chemical liquid with high accuracy and monitor a leakage of an incompressible medium from a region between a piston and a cylinder. A pump has a flexible tube for partitioning a pump chamber and a drive chamber, and the incompressible medium is supplied to the drive chamber by the piston reciprocating in a cylinder hole of the cylinder. A bellows cover is provided between the piston and the cylinder, and forms a seal chamber continuous to a sliding face of the piston. A seal-chamber pressure sensor is attached to the cylinder so as to detect the pressure of the incompressible medium for sealing enclosed in the seal chamber, and a deterioration degree of a seal member is determined by detecting the pressure in the seal chamber.

Abstract: Methods and apparatus employing inert gases injected into the lower level of sloping underground oil-bearing formations as a driving mechanism and water injected into the upper level of the formations as a gas blocking mechanism for increasing and extending the production of oil from underground formations is described. Also described is an inert gas oil production system comprising an exhaust gas processing system, a well inert gas and water injection system, an oil production well system, and a fuel gas generator. A hydraulically operated crude oil pump is also described.

Abstract: A hand operated flexible bulb for use with a liquid dipensing apparatus 5, the bulb comprises an open ended neck 2 which is securable in an air tight manner to a liquid dispensing apparatus. The flexible bulb is provided with an air inlet 6 separate from the open ended neck, the air inlet having a valve 7 associated therewith such that on application of hand pressure to the bulb, the valve closes to force air through the open ended neck and on release of pressure, the valve opens drawing air into the inlet.

Abstract: Information management systems and methods can be used with at least one pharmaceutical compounding device. The systems and methods comprise a controller coupled to the compounding device. A compounding control manager resides on the controller to receive compounding order input and generate control commands to the compounding device based, at least in part, upon the compounding order input. An order process control manager is in data communication with the compounding control manager to communicate compounding order input to the compounding control manager. The order entry process manager includes an order function for receiving entry of compounding order input through a browser-based interface. The browser-based interface can include an order entry workstation separate from the compounding device, or a network of order entry workstations separate from the compounding device, or can reside on the controller.

Abstract: A hydro-elastic pumping system formed from an elastic tube element having attached end members with different hydroimpedance properties, wherein the elastic element is pinched with certain frequency and duty cycle to form asymmetric forces that pump fluid.

Abstract: An electronic apparatus includes a component to which a pressure is applied or which provides vibration, a heat absorbing member, a heat dissipating member, an elastomer bag which receives a pressure or the vibration from the component, a first check valve connected to a port of the elastomer bag, a second check valve connected to another port of the elastomer bag, and a coolant which flows passing through the heat absorbing member, the first check valve, the elastomer bag, the second check valve, and said heat dissipating member.

Abstract: The invention relates to a dosing pump comprising a chamber, an inlet valve located in an inlet pertaining to said chamber, and an outlet valve located in an outlet pertaining to said chamber. The chamber is divided into two partial chambers (2, 18) by a separating means. Said separating means comprises a separating valve (38) which opens in the direction of conveyance and which connects the partial chambers (2, 18). The separating means can be moved back and forth in the direction of conveyance and is connected to a drive device for this purpose. When the separating means is moved in the direction of conveyance, dosing liquid is sucked in via the inlet valve (6) and is simultaneously discharged via the outlet valve (28). This process is carried out smoothly and continuously.

Abstract: A pinch mechanism, which can be used as part of a pump, includes a deformable tube (10) enclosed within a body (11) which has a first chamber (11a). The deformable tube (10) defines a flow passage. A second chamber (19) is coupled via passage (17) to the first chamber (11a). A piston (20) is located within the second chamber (19) and movable between first and second positions. Upon moving to the first position a pressure increase occurs in the first chamber (11a). Upon moving to the second position a negative pressure is created in the first chamber (11a). A vent means (25) is located at a point during movement of the piston (20) between the first and second positions which enables pressure equalisation within the second chamber (19) to occur.

Abstract: A mechanical bladder pump is provided for collecting fluid samples from a well. The pump includes an outer tubular member having a longitudinal bore, and an inner tubular member arranged within the bore of the outer tubular member. The inner and outer tubular members are connected at their lower ends to a compressible bladder, and are arranged for oscillating movement relative to each other to expand and compress the bladder. The lower end of the bladder is open to an inlet passage, and the upper end of the bladder is open to an outlet passage. First and second check valves are provided to control the flow of fluid through the bladder during operation of the pump. A return spring is used to store energy during a tension stroke of the inner tubular member and to release energy during a compression stroke thereof. The pump provides highly representative samples of groundwater.

Abstract: A piezoelectrically driven fluid pump includes a chamber having two opposite sidewalls formed by flexible membranes, and an inlet and an outlet each regulated by a valve. Separate piezo elements are fixed to each of the membranes, to flex the membranes and increase or reduce the chamber volume and thereby draw fluid into the chamber or expel fluid from the chamber. The valves are each formed by two adjacent piezo elements that are supported or flexibly joined together at two opposite ends. When actuated, the valve piezo elements flex outward between the two opposite ends, opening the valve to form an aperture between the two piezo elements. In another embodiment, a fluid pump includes a chamber having one flexible membrane sidewall. A valve-regulated inlet or outlet aperture through the membrane communicates with the pump chamber. A ring-shaped piezo centered around the aperture, on the membrane, flexes the membrane.

Abstract: An assembly for dispensing liquid food product from a food warmer and dispenser that includes a disposable pump. The disposable pump includes a portioning chamber having a hollow open interior that can receive a supply of food product. The disposable pump includes a one-way inlet valve and a one-way outlet valve to control the flow of food product through the disposable pump. The assembly further includes a compressing device positioned to compress the outer wall of the disposable pump to force food product out of a dispensing portion of the pump. The compressing device includes a pair of actuating arms movable about a pivot point positioned between their inner and outer ends. The inner end of each actuating arm is coupled to a drive member that moves the inner ends of each actuating arm toward and away from each other. As the actuating arms move, the outer ends of the actuating arms compress the disposable pump to dispense food product.

Abstract: The bladder, of flimsy ptfe tubing, is attached to the stem of an end-fitting. The stem is formed with a helical screw-thread form. The tubing is heat-shrunk down over the stem. Then, a helical coil spring is screwed onto the form, whereby the thickness of the ptfe tubing lies trapped and squeezed between the stem and the spring. This manner of attaching the bladder to the stem is mechanically adequate even when the bladder tubing is of small diameter.

Abstract: A fluid-handling system capable, in various embodiments, of storing, mixing, and dispensing fluids, and also regulating the flow of fluids. The system includes a cartridge having a non-expandable housing, and a bladder within the housing. In some variations, a drive-liquid is introduced into a region between the housing and the bladder, which causes fluid contained within the bladder to dispense. In some other variations, the drive-liquid is introduced into the bladder, which causes the bladder to expand and expel fluid that is contained with the housing.

Abstract: A pinch mechanism, which can be used as part of a pump, includes a deformable tube (10) enclosed within a body (11) which has a first chamber (11a). The deformable tube (10) defines a flow passage. A second chamber (19) is coupled via passage (17) to the first chamber (11a). A piston (20) is located within the second chamber (19) and movable between first and second positions. Upon moving to the first position a pressure increase occurs in the first chamber (11a). Upon moving to the second position a negative pressure is created in the first chamber (11a). A vent means (25) is located at a point during movement of the piston (20) between the first and second positions which enables pressure equalisation within the second chamber (19) to occur.

Abstract: The present invention provides an infusion pump 10 for providing a flow of a liquid through an tube 28. The infusion pump 10 includes at least two occluders 152, 162 having an open position and a closed position for releasably pinching-off the tube 28. A metering chamber is disposed between the two occluders 152, 162. A first plunger 72 and a second plunger 73 are provided, each plunger 72, 73 having an open position and a closed position for releasably compressing the metering chamber. In the method of the present invention, an occluder 152 releasably pinches-off the tube near the source of the liquid at a first location. The second occluder 162 releasably pinches-off the tube at a second location that is downstream from the source of the liquid 23 and the first location.

Abstract: There is provided a system for supplying a fixed amount of fluid in which the reverse flow of the fluid is eliminated and a precise fixed amount of the fluid can be delivered. In a system for supplying a fixed amount of fluid comprising a fluid accommodating unit comprising a fluid accommodating bag and a pump connected to the fluid accommodating bag and a fluid supplying device body in which the fluid accommodating unit is detachably disposed and a pump driving mechanism for driving the pump is disposed, the pump of the fluid accommodating unit is a bellows pump having two check valves; the check valve comprises a valve base having through-holes formed therein and whose downstream surface is curved to be convex toward the downstream and a valve body made from an elastic thin plate for covering the downstream surface of the valve base and having a hole at the center thereof; and the pump driving mechanism drives a bellows so as to expand and contract it at a predetermined stroke.

Abstract: A liquid pump for pumping groundwater samples from small diameter sub-terrain wells, comprising a tubular casing having inlet apertures, a top cap provided with a fluid communication port and a liquid outlet port, a top bladder mandrel secured to the top cap, a mandrel sealing member disposed in a lower end of the casing, a bottom bladder mandrel secured to the mandrel sealing member, and a flexible bladder extending between the top bladder mandrel and the bottom bladder mandrel and defining a liquid chamber for receiving the liquid therein and a fluid chamber for receiving a fluid under pressure therein that surrounds the liquid chamber, with the bladder disposed therebetween. The fluid chamber is in fluid communication with the fluid communication port connected to a source of the actuating gas, while the liquid chamber is in one-way fluid communication with the liquid inlet and the liquid outlet port.

Abstract: The invention relates to a dosing pump comprising a chamber, an inlet valve located in an inlet pertaining to said chamber, and an outlet valve located in an outlet pertaining to said chamber. The chamber is divided into two partial chambers (2, 18) by a separating means. Said separating means comprises a separating valve (38) which opens in the direction of conveyance and which connects the partial chambers (2, 18). The separating means can be moved back and forth in the direction of conveyance and is connected to a drive device for this purpose. When the separating means is moved in the direction of conveyance, dosing liquid is sucked in via the inlet valve (6) and is simultaneously discharged via the outlet valve (28). This process is carried out smoothly and continuously.

Abstract: A linear pump for pumping a fluid includes a generally tubular shaped bladder 50 sealingly engaged on each end to an end cap 20, 25, forming an inner chamber 14, and including each of an inlet 70 and an outlet 75 inner chamber check valve to fluidly interconnect the inner chamber with the fluid. Each of a plurality of linear motors 40 each may be connected on one end to a respective support rib 30 and on an opposing end pivotally connected to one of the end caps. The support ribs are flexible and have a central portion of the rib engaged with a central portion of the bladder. The plurality of linear motors may be selectively actuated to cause the plurality of support ribs to alternately flex and/or straighten out such that the bladder is condensed or expanded respectively to effect a change in volume of the inner chamber, thereby drawing in or displacing fluid. Bladder extensions 160 may be used to slidably connect the bladder to a respective rib.

Abstract: A piezoelectrically driven fluid pump includes a chamber having two opposite sidewalls formed by flexible membranes, and an inlet and an outlet each regulated by a valve. Separate piezo elements are fixed to each of the membranes, to flex the membranes and increase or reduce the chamber volume and thereby draw fluid into the chamber or expel fluid from the chamber. The valves are each formed by two adjacent piezo elements that are supported or flexibly joined together at two opposite ends. When actuated, the valve piezo elements flex outward between the two opposite ends, opening the valve to form an aperture between the two piezo elements. In another embodiment, a fluid pump includes a chamber having one flexible membrane sidewall. A valve-regulated inlet or outlet aperture through the membrane communicates with the pump chamber. A ring-shaped piezo centered around the aperture, on the membrane, flexes the membrane.

Abstract: The present invention provides an infusion pump 10 for providing a flow of a liquid through an tube 28. The infusion pump 10 includes at least two occluders 152, 162 having an open position and a closed position for releasably pinching-off the tube 28. A metering chamber is disposed between the two occluders 152, 162. A first plunger 72 and a second plunger 73 are provided, each plunger 72, 73 having an open position and a closed position for releasably compressing the metering chamber. In the method of the present invention, an occluder 152 releasably pinches-off the tube near the source of the liquid at a first location. The second occluder 162 releasably pinches-off the tube at a second location that is downstream from the source of the liquid 23 and the first location.

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: A method and apparatus for dispensing a fluent material such as a beverage. The fluent material is dispensed directly from a flexible bag to a container without any intervening structure which contacts the fluent material. Accordingly, the apparatus can be constructed of less expensive materials and does not require frequent cleaning. The apparatus has particular application where aseptic conditions need to be maintained such as in the packaging of the food and medicine. A flow control is adapted to receive at least a portion of one flexible bag and to deform the bag to produce flow of fluent material out of the bag without contact of the fluent material by the flow control.

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. A merchandiser has a pump and a flexible bag which is deformed to selectively dispense fluent material.

Abstract: A disposable cassette for use with a medical infusion pump. An elastomeric membrane is captured between a facing member and a base of the cassette and is displaced into a pumping chamber. The elastomeric membrane includes a generally T-shaped lip, and corresponding grooves are provided on the facing member and base. As the cassette is assembled, an interference fit between the lip and the grooves causes the membrane to stretch taut and to be securely anchored, eliminating a break-in period when the cassette is initially used. “Lobes” of increased thickness provided on the undersurface of a portion of the elastomeric membrane overlying the pumping chamber reduce the residual volume of the pumping chamber, thereby reducing the volume of air retained within the chamber and increasing the accuracy of the cassette. The lobes also sweep air bubbles from the sides of the pumping chamber during operation, further reducing air bubbles retained in the pumping chamber.

Abstract: The linear pump (10,110) includes a housing (12, 112) and either two(20, 22) or one (120) flexible bladders each within a pump housing and interconnected to respective end caps (30, 32, 130, 132, 134, 136). Upon movement of a movable end cap relative to a stationary end cap, the volume in each bladder may be variably controlled to pump blood or another selected fluid. Linear movement of the end caps may be controlled by an attractive or repulsive force between end caps. The pump (110) with a permeable bladder (120) may be used to pump wastewater.

Abstract: A piezoelectric vacuum pump that includes a diaphragm comprising an upper diaphragm member and a lower diaphragm member. The diaphragm members preferably comprise thin metal sheets that are plated with a noble metal, such as gold, silver, or platinum, and are mated together so as to form a hermetic seal along the length of the diaphragm. The piezoelectric vacuum pump further includes a plurality of piezoelectric bimorph elements that are mounted to the upper surface of the upper diaphragm member. When the piezoelectric bimorph elements are electrically activated, they cause a localized portion of the upper diaphragm member to flex, thereby creating a change in volume in a portion of the diaphragm proximate to that piezoelectric bimorph element.

Abstract: A medication delivery system delivers medication to a patient and is suitable for sterilization by a sterilization fluid. The system includes a base and a reservoir disposed about the base for storing the medication. A pump for delivering the medication to the patient is supported by the base. The pump includes a housing having an inlet and an outlet. The inlet and outlet alternate between an open and a closed state to deliver the medication. A port extends from the base. The port fluidly communicates with the reservoir and the pump during sterilization to provide access for the fluid to flow into the reservoir and the pump. An actuator is disposed in the base. The actuator operatively engages the inlet and outlet to retain them in the open state during sterilization. As such, the fluid can penetrate into the reservoir, the inlet, the housing, and the outlet to sterilize the system.

Abstract: A catheter for use in vasculature or other body lumen includes a fluid injection bypass tube, leading to a elastically compressible pump bulb. Upon compression of the pump bulb, fluid such as contrast solution is injected through a one-way valve, into the catheter manifold lumen, and ultimately to the distal end of the catheter lumen, and into the patient vasculature. The one-way valve between the pump bulb and the catheter lumen has a threshold pressure to prevent unintended aspiration of fluid from the pump bulb during aspiration of fluid from the catheter itself.

Abstract: The present invention provides an infusion pump 10 for providing a flow of a liquid through an tube 28. The infusion pump 10 includes at least two occluders 152, 162 having an open position and a closed position for releasably pinching-off the tube 28. A metering chamber is disposed between the two occluders 152, 162. A first plunger 72 and a second plunger 73 are provided, each plunger 72, 73 having an open position and a closed position for releasably compressing the metering chamber. In the method of the present invention, an occluder 152 releasably pinches-off the tube near the source of the liquid at a first location. The second occluder 162 releasably pinches-off the tube at a second location that is downstream from the source of the liquid 23 and the first location.

Abstract: A liquid pump for pumping groundwater samples from small diameter sub-terrain wells. The pump comprises a tubular casing having swaged ends and provided with inlet apertures on its side wall, a top cap and a bottom cap each provided with a bladder mandrel, a coil spring biasing the caps, a flexible bladder separating the interior of the pump into a liquid chamber and a gas chamber, and a pair of poppet valves preventing backflow of the pumped liquid. The pump is actuated by alternately pressurizing and de-pressurizing the actuating gas, preferably air, in the gas chamber causing the bladder to alternately contract and relax. The bladder is formed with reduced diameter ends that allows for an increased stroke volume of the pump. The pump is operated by a precision dual range controller, specifically adapted for “low flow” sampling.

Abstract: There is provided a system for supplying a fixed amount of fluid in which the reverse flow of the fluid is eliminated and a precise fixed amount of the fluid can be delivered. In a system for supplying a fixed amount of fluid comprising a fluid accommodating unit comprising a fluid accommodating bag and a pump connected to the fluid accommodating bag and a fluid supplying device body in which the fluid accommodating unit is detachably disposed and a pump driving mechanism for driving the pump is disposed, the pump of the fluid accommodating unit is a bellows pump having two check valves; the check valve comprises a valve base having through-holes formed therein and whose downstream surface is curved to be convex toward the downstream and a valve body made from an elastic thin plate for covering the downstream surface of the valve base and having a hole at the center thereof; and the pump driving mechanism drives a bellows so as to expand and contract it at a predetermined stroke.

Abstract: The propulsion device (10) includes a housing (12) having an incoming end cap (14) and an outflowing end cap (16). A tubular bladder (20) within the housing is interconnected to each end cap, thereby varying the volume of both a chamber (22) within the bladder and a chamber (24) between the bladder and the housing during attractive or repulsive movement between end caps (14,16). Check valves control the flowthrough the end caps. The propulsion device is highly efficient and is able to move the vessel through water with little or no cavitation.

Abstract: An air pump comprises a hollow pump body, at least one pulling member, an air inlet and an air outlet. The hollow pump body has air inside and consist of flexible sides and two opposite stiff ends. The air outlet is provided on the pump body to discharge the air in the pump body when the pump body is pressed. The pulling member is attached to one of the stiff ends of the pump body in order to restore the pressed pump body by pulling the pulling member. The air inlet is provided on the pump body to suck outside air into the pump body when the stiff end is pulled by the pulling member to restore the shape of the pressed pump body.