An apparatus for directing fluid flow is disclosed, including a valve structure having a chamber, a main port, a first port, and a second port, each of the ports being connected to the chamber. A poppet structure in the chamber is moveable between a first position blocking the first port and a second position blocking the second port. A first compliant member connecting the poppet structure to an inner wall of the chamber, is configured to alternate application of forces to the poppet structure, in opposite directions, between the first and second positions.

A pump cassette is disclosed. The pump cassette includes a housing having at least one fluid inlet line and at least one fluid outlet line. The cassette also includes at least one reciprocating pressure displacement membrane pump within the housing. The pressure pump pumps a fluid from the fluid inlet line to the fluid outlet line. A hollow spike is also included on the housing as well as at least one metering pump. The metering pump is fluidly connected to the hollow spike on the housing and to a metering pump fluid line. The metering pump fluid line is fluidly connected to the fluid outlet line.

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.

An apparatus for directing fluid flow is disclosed, including a valve structure having a chamber, a main port, a first port, and a second port, each of the ports being connected to the chamber. A poppet structure in the chamber is moveable between a first position blocking the first port and a second position blocking the second port. A first compliant member connecting the poppet structure to an inner wall of the chamber, is configured to alternate application of forces to the poppet structure, in opposite directions, between the first and second positions.

An apparatus for continuously controlling fluid flow in a sewer conduit, comprising: a) moisture sensors detecting levels of fluid in this conduit; b) an inflatable bladder, mounted in the sewer conduit for releasably sealing in fluid tight fashion a section of this conduit; a compressed air source for inflating the bladder; and a control box including a CPU sensitive to the moisture sensor(s) and actuating the air compressor responsively to conduit fluid level conditions reaching beyond a preset threshold value. The performance of the apparatus is independent of the speed of fluid flow in the sewer conduit.

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. In another aspect, a system for monitoring the adequacy of blood flow in a blood line of the hemodialysis apparatus allows a controller to suspend dialysate pumping operations if the adequacy of blood flow in the blood line is sub-optimal, and to present information on a display on the quality of blood flow in the blood line.

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.

Automated control mechanisms and methods for controlling fluid flow in a hemodialysis apparatus are described. The methods can involve a controller receiving information from a pressure sensor in a control chamber of a reciprocating diaphragm-based blood pump and causing the application of a time-varying pressure waveform on a diaphragm of the blood pump during a fill-stroke of the blood pump. The controller can be configured and programmed to monitor a pressure variation in the control chamber measured by the pressure sensor and to compare the measured pressure variation to a pre-determined value. Based on such comparison, the controller can initiate a procedure to pause or stop a dialysate pump of the hemodialysis apparatus if the magnitude of the measured pressure variation deviates from the pre-determined value.

A pumping cassette including a housing having at least two inlet fluid lines and at least two outlet fluid lines. At least one balancing pod within the housing and in fluid connection with the fluid paths. The balancing pod balances the flow of a first fluid and the flow of a second fluid such that the volume of the first fluid equals the volume of the second fluid. The balancing pod also includes a membrane that forms two balancing chambers. Also included in the cassette is at least two reciprocating pressure displacement membrane pumps. The pumps are within the housing and they pump the fluid from a fluid inlet to a fluid outlet line and pump the second fluid from a fluid inlet to a fluid outlet.

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.