Patent ID: 6364623
Filing Date: 2002-04-02
Classification: F04B

Abstract:
A method of detecting gas in a fluid transported through a fluid delivery system comprising a first pump head having a first piston actuating in a first direction and a second direction within a first piston chamber and a second pump head having a second piston actuating in a first direction and a second direction within a second piston chamber, said first pump head receiving said fluid and pressurizing said fluid to form a pressurized fluid and said second pump head receiving said pressurized fluid from said first pump head, comprising the steps of:determining a minimum travel of said first pump head required to maintain gas in solution in said fluid; implementing a minimum travel of said first pump head required to maintain gas in solution in said fluid; monitoring compression volume of said pressurized fluid compressed by said first piston within said first piston chamber to determine a compression volume; monitoring decompression volume of said pressurized fluid within said first piston chamber to determine a decompression volume; determining a compression to decompression volume ratio representing a ratio of said compression volume to said decompression volume; determining a threshold level of said ratio of said compression volume to said decompression volume; determining if said compression to decompression volume ratio exceeds said threshold level; and if said compression to decompression volume ratio exceeds said threshold level changing a stroke volume of said first pump head to expel gas from said fluid and determining a new minimum travel of said first pump head required to maintain gas in solution said fluid.