Abstract:
Hemodialysis and similar dialysis systems including a variety of systems and methods that make hemodialysis more efficient, easier, and/or more affordable, and include new fluid circuits for fluid flow in hemodialysis systems and a reciprocating diaphragm pump for pumping fluids. The reciprocating diaphragm pump includes a flexible diaphragm, a first rigid body having a curved pumping chamber wall, a second rigid body having an opposing curved control chamber wall. The diaphragm is interposed between the pumping chamber wall and the control chamber wall to define a pumping chamber and a control chamber. The diaphragm of the pump has a peripheral bead arranged to locate the diaphragm between the first rigid body and the second rigid body and a diaphragm body having a curved, semi-spheroid or domed shape. The diaphragm is pre-formed or molded so that during a delivery stroke of the pump, the elastic force of the diaphragm resisting its deployment into the pumping chamber prevents a peripheral portion of the diaphragm body from fully contacting the pumping chamber wall.
Abstract:
Membrane pump device, wherein the membrane pump device comprises a housing, and the housing contains a first and a second chamber, wherein the first chamber is separated from the second chamber by a movable membrane, while a liquid being pumped can be introduced in the first chamber, and a drive liquid can be introduced into the second chamber, wherein the second chamber has an outlet opening, and the outlet opening is present on an outer side of the housing. The membrane pump device is characterized in that the membrane pump device comprises a valve, while the valve is arranged at the outlet opening and closes off the second chamber from the outside.
Abstract:
An elongate air operated pump includes a pump chamber, a bladder inside the pump chamber, inlet and outlet valves to and from the chamber and an air control system. The air control system includes a control valve alternately communicating compressed air and exhaust to atmosphere to a venturi with a first end, a second end and a throat port. The first end of the venturi receives continuous compressed air. The second end receives the alternately communication of compressed air and exhaust to atmosphere from the control valve. The throat port of the venturi is in continuous communication with the bladder to pressurize and draw a vacuum on the bladder. The valves may be pneumatic pinch valves controlled by the control valve to cycle with the bladder or passive one-way pump valves.
Abstract:
A cassette integrated system. The cassette integrated system includes a mixing cassette, a balancing cassette, a middle cassette fluidly connected to the mixing cassette and the balancing cassette and at least one pod. The mixing cassette is fluidly connected to the middle cassette by at least one fluid line and the middle cassette is fluidly connected to the balancing cassette by at least one fluid line. The at least one pod is connected to at least two of the cassettes wherein the pod is located in an area between the cassettes.
Abstract:
A double-diaphragm pump comprising a pair of axially spaced apart pumping chambers, each chamber having a pumping diaphragm which divides each chamber into an inner and outer compartment, the inner ends of both pumping chambers being closed by a central element, means for supplying fluid to the outer compartments to cause the diaphragms to oscillate and vary the capacities of the inner compartments and each of the inner compartments having an inlet and an outlet port leading to unidirectional valves to allow fluid to be drawn into one of the compartments when the appropriate diaphragm moves outwardly and expelled from that compartment when the diaphragm moves inwardly, and in which the unidirectional valves are located in inlet and outlet manifolds in the central element and are accessed and fitted through the inlet and outlet ports in the inner compartments.
Abstract:
A diaphragm pump with a multi-part pump body is described. The pump consists at least of three rigid plates (201, 203, 205) and at least two elastic diaphragms (204, 202) arranged between these plates (201, 203, 205), the plates (201, 203, 205) forming, in particular, a pumping chamber (211) and at least two shut-off chambers (210, 212), in each case with an inlet (240) and an outlet (241) orifice for the conveyable material, and the pumping chambers (211) and shut-off chambers (210, 212) forming, together with an inlet duct (207), the connecting ducts (208) and (209) and an outlet duct (206), a passage duct, the pumping chamber (211) and the shut-off chambers (210, 212) being separated by the diaphragms (204, 202) in each case into a product space (230, 231, 232) and a control space (220, 221, 222), and the control spaces (220, 221, 222) having control lines (119, 120, 121) which are connected to a control unit (100, 115).
Abstract:
A dual pump for independently pumping two fluids includes a pump body having a first concave depression on a first side of the body. A first inlet port and a first outlet port are contained within the body, in fluid communication with the first depression. A second concave depression is on a second side of the body opposite the first depression. A second inlet port and a second outlet port are contained within the body in fluid communication with the second depression. A first diaphragm is coupled to the first side of the body and encloses the first depression to form a first inner chamber. A second diaphragm is coupled to the second side of the body and encloses the second depression to form a second inner chamber. A shell encloses the body on its first and second sides. The shell defines a first outer chamber with the first diaphragm in pressure communication with the first inner chamber. The shell also defines a second outer chamber with the second diaphragm in pressure communication with the second inner chamber. A first pressure port in the shell provides a first pressure passage to the first outer chamber. A second pressure port in the shell provides a second pressure passage to the second outer chamber. Advantages include simultaneously and independently providing two fluid pumps within a pump that is substantially the same size as a conventional single pump. Alternatively, the pump is configured to supply a continuous, non-pulse flow of a single liquid.
Abstract:
An improved dual-stage pump system is provided for the accurate pumping and filtering of viscous fluids. Two hydraulically activated pumps are provided in series with a filter and reservoir disposed in-line between the two pumps. The reservoir acts as a source bottle for the second pump and allows the first pump to pump the viscous fluid through the filter at a rate independent of the dispensing rate of the second pump. By operating the first pump at a rate independent of the second pump, back pressure at the filter is avoided. Each hydraulically activated diaphragm pump is equipped with an improved diaphragm that is pre-formed to the geometries of the process fluid cavity thereby eliminating any inaccuracies in the operation of the pumps due to expansion of retraction of the diaphragm during pump operation.
Abstract:
An electromechanical transducer drives a resonator plate, which develops oscillating pressure in a contacting liquid. A high-speed check valve rectifies the pressure oscillations, causing pumping. On the driver side of the valve, the high inertial flow impedance in a narrow passageway confines oscillating pressure while admitting non-oscillating fluid flow. On the valve side opposite the driver, a volumetric compliance element decouples the inertia of the fluid passageway to permit fast acceleration and deceleration of fluid pulsing through the valve. A high-speed passive check valve consists of a thin-section o-ring covering a circular slot, with circumferential tension setting the forward bias pressure. Pump frequencies above one kilohertz and microliter stroke volumes are practical. Electrical impedance measurements on the pump indicate fluid volume in the pump. A coupling of two pumps in series and an alternation of pumping and volume measurement operations in the coupled pumps leads to volumetric metering of fluid.
Abstract:
Provision is made for an air control valve to bypass the ice forming exhaust of a reciprocating pressure activation chamber in a reciprocating double diaphragm pump utilizing the supply pressure to close a check valve in line between the valve and the chamber which is then opened to exhaust by exhaust fluid flow from the chamber.