04493693 is referenced by 37 patents and cites 23 patents.

A monitoring system for monitoring trans-membrane pressure in plasmapheresis apparatus utilizing a microporous membrane type filter includes first and second pressure-to-frequency transducer circuits for developing signals frequency-indicative of the inlet and outlet pressures of the filter. The signals are digitally compared in a pulse subtraction circuit to produce an output signal frequency-indicative of trans-membrane pressure. The output signal is applied to a periodically reset display counter to develop a digital readout of trans-membrane pressure. Porous filter elements in the flow system and in the inlet port of each transducer isolate bacteria within the flow system, prevent contamination of the transducers, and provide a time constant for each transducer which prevents transient flow variations in the system from causing erroneous trans-membrane pressure readings.

Title
Trans-membrane pressure monitoring system
Application Number
6/403362
Publication Number
4493693
Application Date
July 30, 1982
Publication Date
January 15, 1985
Inventor
Walker P Woodworth
Vernon Hills
IL, US
John T Foley
Wheeling
IL, US
Arnold C Bilstad
Deerfield
IL, US
Agent
Daniel D Ryan
Eugene M Cummings
Paul C Flattery
Assignee
Baxter Travenol Laboratories
IL, US
IPC
B01D 19/00
A61A 1/03
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