Abstract: An improvement is provided to a pressurized close-cycle machine that has a cold-end pressure vessel and is of the type having a piston undergoing reciprocating linear motion within a cylinder containing a working fluid heated by conduction through a heater head by heat from an external thermal source. The improvement includes a heat exchanger for cooling the working fluid, where the heat exchanger is disposed within the cold-end pressure vessel. The heater head may be directly coupled to the cold-end pressure vessel by welding or other methods. A coolant tube is used to convey coolant through the heat exchanger.

Abstract: An improvement is provided to a pressurized close-cycle machine that has a cold-end pressure vessel and is of the type having a piston undergoing reciprocating linear motion within a cylinder containing a working fluid heated by conduction through a heater head by heat from an external thermal source. The improvement includes a heat exchanger for cooling the working fluid, where the heat exchanger is disposed within the cold-end pressure vessel. The heater head may be directly coupled to the cold-end pressure vessel by welding or other methods. A coolant tube is used to convey coolant through the heat exchanger.

Abstract: An improvement is provided to a pressurized close-cycle machine that has a cold-end pressure vessel and is of the type having a piston undergoing reciprocating linear motion within a cylinder containing a working fluid heated by conduction through a heater head by heat from an external thermal source. The improvement includes a heat exchanger for cooling the working fluid, where the heat exchanger is disposed within the cold-end pressure vessel. The heater head may be directly coupled to the cold-end pressure vessel by welding or other methods. A coolant tube is used to convey coolant through the heat exchanger.

Abstract: An improvement is provided to a pressurized close-cycle machine that has a cold-end pressure vessel and is of the type having a piston undergoing reciprocating linear motion within a cylinder containing a working fluid heated by conduction through a heater head by heat from an external thermal source. The improvement includes a heat exchanger for cooling the working fluid, where the heat exchanger is disposed within the cold-end pressure vessel. The heater head may be directly coupled to the cold-end pressure vessel by welding or other methods. A coolant tube is used to convey coolant through the heat exchanger.

Abstract: An improvement is provided to a pressurized close-cycle machine that has a cold-end pressure vessel and is of the type having a piston undergoing reciprocating linear motion within a cylinder containing a working fluid heated by conduction through a heater head by heat from an external thermal source. The improvement includes a heat exchanger for cooling the working fluid, where the heat exchanger is disposed within the cold-end pressure vessel. The heater head may be directly coupled to the cold-end pressure vessel by welding or other methods. A coolant tube is used to convey coolant through the heat exchanger.

Abstract: An improvement is provided to a pressurized close-cycle machine that has a cold-end pressure vessel and is of the type having a piston undergoing reciprocating linear motion within a cylinder containing a working fluid heated by conduction through a heater head by heat from an external thermal source. The improvement includes a heat exchanger for cooling the working fluid, where the heat exchanger is disposed within the cold-end pressure vessel. The heater head may be directly coupled to the cold-end pressure vessel by welding or other methods. A coolant tube is used to convey coolant through the heat exchanger.

Abstract: The present invention involves, in some embodiments, reusable pump drive systems, which are coupled to removable, and preferably disposable, pumping cartridges. The invention provides, in some embodiments, novel pumping cartridges for use in pumping systems. One such cartridge includes an integrated filter element therein for filtering fluids, for example fluids pumped to the body of a patient in a medical procedure. In some embodiments, the integrated filter is utilized as a blood clot removal filter and in other embodiments is used to remove particulates liquids infused to a patient. The filter element includes a filter with pores therein that are preferably sized to permit essentially unrestricted flow of individual human blood cells therethrough and to block or collect blood clots, cell clumps, particulates etc. with sizes substantially larger than the average size of a human blood cell.

Abstract: An improvement is provided to a pressurized close-cycle machine that has a cold-end pressure vessel and is of the type having a piston undergoing reciprocating linear motion within a cylinder containing a working fluid heated by conduction through a heater head by heat from an external thermal source. The improvement includes a heat exchanger for cooling the working fluid, where the heat exchanger is disposed within the cold-end pressure vessel. The heater head may be directly coupled to the cold-end pressure vessel by welding or other methods. A coolant tube is used to convey coolant through the heat exchanger.

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: A simplified three-way piezoelectric-actuated valve is described. The valve has a valve body having an internal valve cavity, a pair of generally opposed positioning members integral to the valve body, and first, second, and common ports. At least one of the ports has a valve seat and a passageway in communication with the valve seat, the seat and the passageway being integrally formed in the valve body. A piezoelectric actuator has first and second ends. The first end is secured within the valve cavity by the positioning members and has electrical contacts for providing an electric potential to control the position of the second end. The second end is capable of flexing between a first operating position in which the first port is closed and the second port is open, and a second operating position in which the first port is open and the second port is closed.

Abstract: A simplified two-way piezoelectric-actuated valve is described. The valve has a valve body having an internal valve cavity, a pair of generally opposed positioning members integral to the valve body, and first and second ports. At least one of the ports has a valve seat and a passageway in communication with the valve seat, the seat and the passageway being integrally formed in the valve body. A piezoelectric actuator has first and second ends. The first end is secured within the valve cavity by the positioning members and has electrical contacts for providing an electric potential to control the position of the second end. The second end is capable of flexing between a closed position with respect to the valve seat and an open position with respect to the valve seat. A three-way version of the valve is also described, as is a method of manufacturing such valves.

Abstract: Pumping mechanisms for performing peritoneal dialysis and the like employ a pumping mechanism comprising a diaphragm that operate in response to applied fluid pressure. Flexible tubing is attached to the pumping mechanism for carrying liquid to and from the patient's peritoneal cavity. An actuating station for pumping mechanism receives the pumping mechanism and attached tubing. A pressure transfer element conveys fluid pressure to the diaphragm for moving liquid through the cassette. An occluder element contacts and crimps closed the tubing attached to the cassette. A first reservoir inflates with positive fluid pressure for contacting the pressure transfer element to hold it in operative contact against the diaphragm. A second reservoir inflates with positive fluid pressure for contacting the occluding element to hold it away from crimping contact with the tubing. At least one of the first and second reservoirs also transports fluid pressure to the pressure transfer element for conveyance to the diaphragm.

Abstract: Pumping mechanisms for performing peritoneal dialysis and the like employ a pumping mechanism comprising a diaphragm that operate in response to applied fluid pressure. Flexible tubing is attached to the pumping mechanism for carrying liquid to and from the patient's peritoneal cavity. An actuating station for pumping mechanism receives the pumping mechanism and attached tubing. A pressure transfer element conveys fluid pressure to the diaphragm for moving liquid through the cassette. An occluder element contacts and crimps closed the tubing attached to the cassette. A first reservoir inflates with positive fluid pressure for contacting the pressure transfer element to hold it in operative contact against the diaphragm. A second reservoir inflates with positive fluid pressure for contacting the occluding element to hold it away from crimping contact with the tubing. At least one of the first and second reservoirs also transports fluid pressure to the pressure transfer element for conveyance to the diaphragm.