Patent ID: 8662859
Filing Date: 2014-03-04
Classification: F04B

Abstract:
1. A method for controlling fluid pressure in a multi-stage pump, comprising: accessing a baseline profile for a known good dispense cycle, wherein the baseline profile provides a profile of an operating parameter of the multi-stage pump; operating a feed pump, a dispense pump and a set of valves to perform a new dispense cycle including multiple segments, comprising a dispense segment and at least one additional segment in which fluid is not dispensed, wherein the dispense pump comprises a diaphragm that moves within a dispense chamber to displace fluid, a motor driven piston in contact with the diaphragm and a motor coupled to the piston; continually determining values of the operating parameter during the new dispense cycle including during the dispense segment and the at least one additional segment; creating a first operating profile for the operating parameter using the determined values of the operating parameter; comparing the first operating profile of determined values with the baseline profile to determine if the new dispense cycle resulted in a good dispense, wherein comparing the first operating profile with the baseline profile comprises comparing each of a plurality of the determined values from the operating profile to a corresponding one of a plurality of values from the baseline profile; and if the good dispense did not occur, performing one or more of sending an alarm and changing an operation of the multi-stage pump.