Patent ID: 8685218
Filing Date: 2014-04-01
Classification: B01D,G01N,G05D,Y10T

Abstract:
1. A low flow rate precision flow controller system comprising: (a) a plurality of continuously variable pressure fluid supplies delivering a plurality of fluids; (b) a single fluid outlet being in fluid communication with the plurality of fluid supplies, the plurality of fluids being mixed before exiting through the outlet; (c) a plurality of pressure sources corresponding to the plurality of fluids, each pressure source applying pressure to each fluid; (d) a plurality of capillary tube thermal mass flowmeters, each flowmeter detecting the flow rate of each fluid of the corresponding plurality of fluids; and (e) a controller for electronic flow control in communication with the respective flowmeter and the respective pressure source, wherein the controller compares the respective measured flow rate to a respective desired flow rate and adjusts the respective pressure source so that the respective fluid flows at the respective desired flow rate, wherein the fluids flow out of the fluid outlet at a flow rate of less than approximately 100 microliters/minute.