Patent · US Active

Capacitive fluid level sensing

US10564025B2 · kind B2 · utility

2Cited by

7References

20Claims

0Family size

Assignee

HEWLETT-PACKARD DEVELOPMENT COMPANY, L.P. · US

Inventors

Barry J. Oldfield · Boise, US
Nissim Henn · Nes Ziona, IL
Assaf Pines · Rehovot, IL

Key dates

Filing date	Jan 25, 2011
Grant date	Feb 18, 2020
Priority date	—
Expiry date	Mar 5, 2036

Classification

Technology area (CPC G)Physics
CPC primaryG01F25/20
WIPO fieldMeasurement
WIPO sectorInstruments

Abstract

Capacitances are measured for a level measurement capacitive sensor (18) spanning from a lower end to a higher end of a fluid level measurement range (30), a first capacitive calibration sensor (20) below the fluid level measurement range (30), and a second capacitive calibration sensor (22) above the fluid level measurement range (30). A degree to which the lower end of the fluid level measurement range (30) is immersed in a first fluid and the upper end of the fluid level measurement range (30) is immersed in a second fluid is determined based on a capacitance of the level measurement capacitive sensor (18), a first calibration value characterizing the first fluid and derived from a capacitance of the first capacitive calibration sensor (20), and a second calibration value characterizing the second fluid and derived from a capacitance of the second capacitive calibration sensor (22).

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