Patent · US Expired

Composition pulse time-of-flight mass flow sensor

US6675660B1 · kind B1 · utility

37Cited by
6References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 31, 2002
Grant dateJan 13, 2004
Priority date
Expiry dateJul 31, 2022

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S977/955
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A device for measuring fluid flow rates over a wide range of flow rates (<1 nL/min to >10 &mgr;L/min) and at pressures at least as great as 10,000 psi. The invention is particularly adapted for use in microfluidic systems. The device operates by producing compositional variations in the fluid, or pulses, that are subsequently detected downstream from the point of creation to derive a flow rate. Each pulse, comprising a small fluid volume, whose composition is different from the mean composition of the fluid, can be created by electrochemical means, such as by electrolysis of a solvent, electrolysis of a dissolved species, or electrodialysis of a dissolved ionic species. Measurements of the conductivity of the fluid can be used to detect the arrival time of the pulses, from which the fluid flow rate can be determined

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.