3077 results about "Pump chamber" patented technology

The invention relates to membrane pumps for delivering liquids. More specifically, a pump is provided having a pump housing with a pump cavity formed between first and second wall portions thereof, and an pump membrane pump membrane having first and second membrane surfaces arranged within the pump cavity, whereby a pump chamber is provided between the first wall portion and the first membrane surface, and an actuation chamber is provided between the second wall and the second membrane surface. Inlet means comprising an inlet valve in fluid communication with the pump chamber, and outlet means comprising an outlet valve in fluid communication with the pump chamber are provided. The pump membrane has a maximum volume position, and a drained volume position in which the first membrane surface in a stretched state abuts the first wall. To drive the membrane, actuating means for periodically shifting the pump membrane between the maximum volume position and the drained volume position is provided, thereby, in a situation of use, providing a flow of fluid.

A method of dispensing a therapeutic fluid from a line includes providing an inlet line connectable to an upstream fluid source. The inlet line is in downstream fluid communication with a pumping chamber. The pumping chamber has a pump outlet. The method also includes actuating a force application assembly so as to restrict retrograde flow of fluid through the inlet while pressurizing the pumping chamber to urge flow through the pump outlet. A corresponding system employs the method.

Improved integrity test, priming sequence and bag height detection tests, apparatuses and methods for a medical fluid delivery system are provided. The integrity test includes a plurality of air pressure decay tests, using positive and negative pressure. The priming sequence includes pumping fluid through a portion of a patient line to be primed to overcome air in the line and other potential obstacles. The head height test measures a pressure build-up or drop-off within a pump chamber of a membrane pump. The measured pressure corresponds to a head height between a fluid supply and the pump or between the pump and a fluid drain. A determination is made whether the corresponding head height is acceptable.

PCT No. PCT/EP96/05382 Sec. 371 Date Jun. 3, 1998 Sec. 102(e) Date Jun. 3, 1998 PCT Filed Dec. 3, 1996 PCT Pub. No. WO97/21924 PCT Pub. Date Jun. 19, 1997A fluid pump has a pump body and a displacer, the displacer and the pump body being implemented such that a pump chamber is defined therebetween, the pump chamber having an inlet opening and an outlet opening, neither the inlet opening nor the outlet opening being provided with a check valve. A drive means is provided which positions the displacer periodically at a first and at a second end position. The displacer closes the outlet opening when it occupies its first end position and leaves the outlet opening free when it occupies its second end position and leaves the inlet opening free at both end positions thereof. The displacer, when moving from the first to the second end position, defines a flow-through gap which opens between the displacer and the pump body in the area of the outlet opening in dependence upon the movement, the flow-through gap being defined such that the flow through the outlet opening depends on the pressure in the pump chamber as well as on the respective opening degree of the flow-through gap.

A fluid volumetric pumping system has a fluid pump and capacitor plates disposed around a pump chamber of the fluid pump. The capacitance between the capacitor plates changes as the volume of fluid in the pump chamber changes. An electrical circuit measures a change in the capacitance between the plates and outputs a signal indicative of the volume of fluid in the pump chamber. The pump having the capacitance sensor of the present invention fluidly connects to a patient. In an embodiment, a peritoneal dialysis system provides dialysate to the patient via the pump, and the capacitance sensor measures the volume of dialysate supplied to and drained from a peritoneal cavity of the patient.

A device for use in a molten metal pump helps alleviate jams between a rotating rotor and stationary inlet. The device includes an inlet structure including one or more openings and a displacement structure that preferably includes one or more rotor blades. The inlet structure and displacement structure are connected to one another (preferably, but not necessarily, as a unitary piece), thus enabling them both to rotate. A pump including the device is also enclosed. The invention further includes a bearing surface for an impeller or for a device according to the invention, wherein the bearing surface includes grooves that help reduce molten metal build up between the bearing surface of the impeller or device and the bearing surface of a pump chamber.

Presently disclosed is a hydraulic pump device and its use thereof, especially in a fluid delivery system. In one embodiment, the fluid delivery system is an inexpensive, single-use device for slow dosing medicament applications. The fluid delivery system may employ a spring-compressed bellows crank or other combination of simple mechanisms operating according to the well-known peristaltic principle to force a volume of ultrapure bio-inert hydraulic fluid through an aperture, thereby expanding one chamber of a two chamber hydraulic cylinder. The second, fluid storage chamber, containing the medicament, is emptied through a conventional orifice in response to the expansion of the pump chamber. The medicament may thence flow through any suitable infusion set into a patient removeably attached thereto.

Blood component processing systems and methods are coupled to a blood component processing device. The systems and methods include a fluid circuit that comprises at least one fluid pressure actuated pump station, at least one fluid flow path communicating with the pump station, and at least one valve in the fluid flow path. A control module is sized and configured to interact with the fluid circuit. The control module includes an actuator to selectively apply fluid pressure to the pump station in concert with operation of the valve to pump fluid through the fluid flow path in response to a control program. A controller coupled to the control module includes the control program and a fluid circuit integrity test function. The fluid circuit integrity test function commands the control module to selectively apply fluid pressure to the pump station in concert with operation of the valve to introduce a fluid within a region of the fluid circuit and to confine the fluid within the region while applying fluid pressure to the pump chamber. The fluid circuit integrity test function generates an integrity output in response to sensing leakage of fluid from the region.

The present invention generally relates to hemodialysis and similar dialysis systems, including a variety of systems and methods that would make hemodialysis more efficient, easier, and/or more affordable. One aspect of the invention is generally directed to new fluid circuits for fluid flow. According to one aspect, a blood pump is configured to pump blood to a dialyzer of a hemodialysis apparatus, the blood pump comprising a pneumatically actuated or controlled reciprocating diaphragm pump. In an embodiment, the diaphragm of the pump comprises a flexible membrane formed or molded to generally conform to a curved inner wall of a pumping chamber or control chamber of the pump, wherein the diaphragm is pre-formed or molded to have a control side taking a convex shape, so that any elastic tension on the diaphragm is minimized when fully extended into a control chamber of the pump.

A blood processing system comprises a processing chamber to process blood and a fluid flow cassette that communicates with the processing chamber. The cassette comprises a body, a pump chamber formed in the body, and a flexible diaphragm on the pump chamber responsive to an applied fluid pressures for flexure toward and away from the pump chamber to pump fluid through the pump chamber. The cassette also includes a flow path formed, at least in part, in the body to couple the pump chamber in fluid flow communication with the processing chamber, to convey fluid pumped by the pump chamber into the processing chamber. The cassette also includes an in line cavity formed in the body and located in the flow path to trap air to prevent entry of air into the processing chamber.

Impure portions such as air bubbles and gelled portions in a liquid are removed so that the liquid can be discharged with improved cleanliness. Under condition that a return flow path and a liquid discharge flow path are closed, a pump chamber is expanded, thereby sucking the liquid in a liquid container portion into a pump chamber through a filter. Under condition that a vent port of the filter and the return flow path are opened and a liquid introducing flow path, the liquid discharge flow path, and a pump inlet flow path are closed, the pump chamber is contracted, thereby returning the liquid in the pump chamber toward the filter so that air in the filter is exhausted to the outside. Under condition that the return flow path and the pump inlet flow path are closed, the pump chamber is contracted, thereby discharging the liquid from the nozzle.

“A positioning device is provided for positioning pipettes in medical-technical applications including at least one pipetting apparatus with at least one pipette as well as several drive units for positioning a pipette tip and for moving it over a working area and transversely to a working area, a sliding carriage that is moveable transversely to the working area supports the pipette, at least one pump drive with at least one pump and at least one pump chamber is provided for aspirating or dispensing a medium, such that by providing the at least one pump drive with pump and at least one pump chamber integrated in the sliding carriage that is moveable transversely to the working area, the design of the positioning device becomes compact and precise pipetting is achieved.

A disposable pumping cassette in one embodiment includes a pump chamber; and a valve chamber in communication with the pump chamber, the valve chamber including an inlet and first and second outlets. A disposable pumping cassette in another embodiment includes a first valve chamber including an inlet and first and second outlets; and a second valve chamber including an inlet and an outlet, the second valve chamber openable to allow dialysis fluid to flow through one of the first and second outlets of the first valve chamber, through the outlet of the second valve chamber. A disposable pumping cassette in a further embodiment includes a valve chamber including a fluid inlet and first and second fluid outlets; and a flexible sheet openable to open and close only one of the first and second outlets.

A vacuum pump having shock absorption and controlled rotation for use in an artificial limb. The pump includes a housing having a first chamber, and a shaft configured to be received by and to reciprocate within the first chamber, the housing and shaft forming a pump chamber. A piston may be coupled to the shaft and positioned within the pump chamber, and intake and exhaust ports are fluidly coupled to the pump chamber. Rotational structure is mounted with respect to the pump to provide controlled rotation of the shaft relative to the housing, and shock absorption structure is included within the pump to provide shock absorption for the shaft. Both a pneumatic spring and a mechanical spring element may be provided for the shock absorption structure. An optional adapter couples the shaft to the pylon of an integral pylon prosthetic foot.

A diaphragm air pump comprises a pump chamber, a diaphragm and one or more piezoelectric beams or bimorphs. Fluid flows into the pump chamber and then flows out of it, the diaphragm is provided within the pump chamber, and one or more central openings are formed in the diaphragm. One or more central check valves are provided in the central openings. The diaphragm is just bonded with piezoelectric beams, not fixed to the lower housing of the pump chamber in order to get large displacement. With the provided diaphragm air pump, it is possible to actively adjust the air quantity according to the requirement for fuel cell or a part-to-be-cooled, and it is also possible to reduce noise and power consumption compared with a conventional fan type cooler or air pumps.

An implantable pump system includes: an implantable pump having separate chambers or reservoirs; and a catheter having two or more reservoir-specific inlet ports directed into respective lumens of the catheter. In one embodiment, the distal tips of the respective lumens may be directed to different sites within the patient's body, thereby allowing site specific and independent delivery of the medications stored in the respective pump chambers or reservoirs to be administered to different body sites at independently controlled times and rates. In another embodiment, the distal tips of the respective lumens are directed, more or less, to the same body site or tissue region, thereby providing for the independent delivery of multiple medications to the same regions at independently controlled times and rates.