Abstract: A pump apparatus for transferring precise amounts of fluid from a container to a patient has a defined volume pump chamber divided by a first diaphragm to define a first chamber and a second chamber. A pumped fluid enters the first chamber through a one-way valve as the first chamber volume increases and is exhausted through a second one-way valve as the first chamber volume decreases. A third one-way valve is coupled to the first and second one-way valves in such a way as to prevent the pumped fluid from flowing through the pump in response to a pressure head at the input or output ports. A priming chamber is divided by a second diaphragm to define first and second sections, respectively. A passageway extends between the first section and the passageway connecting the second and third one-way valves.

Abstract: A pumping apparatus for moving a pumped fluid from a reservoir to a destination in response to variations in the pressure of a pumping fluid includes a pump housing; a pumping chamber; an input passageway; an exit passageway; and a passageway network between the input passageway and the exit passageway. A diaphragm divides the pumping chamber into first and second volumes for respectively receiving the pumped and the pumping fluids. Apparatus is provided for intermittantly varying the pressure of the pumping fluid. A first diaphragm valve responsive to variations in the pressure of the pumped fluid is positioned between the input passageway and the passageway network. A second valve also responsive to variations in the pressure of the pumped fluid is positioned in the passageway network for being opened when the first valve is closed and visa versa.

Abstract: A pump for transferring precise amounts of fluid from a container to a patient. A pump apparatus has a defined volume pump chamber divided by a diaphragm into a pumping fluid portion and a pumped fluid portion. The pumped fluid portion receives and exhausts pumped fluid in response to a decrease or increase in pressure in the pumping fluid portion of the pump chamber. The diaphragm and the defined volume pumping chamber provide accurate per cycle pumping volumes. The pumping fluid pressure is varied by periodically electrically heating a ribbon filament in a pumping fluid chamber thereby increasing the temperature and therefore the pressure and/or volume of the pumping fluid. The pumped fluid enters the pumping chamber through a one-way valve as the pumped fluid portion volume expands and is exhausted through a second one-way valve as the volume of the pumped fluid portion contracts. Control circuitry is provided to allow variations in the pulse repetition rate and pulsewidth.