Patent · US Expired

Method and apparatus for detecting liquid levels in liquid-storage containers

US7275430B2 · kind B2 · utility

5Cited by
9References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 7, 2005
Grant dateOct 2, 2007
Priority date
Expiry dateOct 7, 2025

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01F23/243
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A method and apparatus for sensing different levels of liquids in their respective containers in a liquid-consuming and/or producing instrument system. According to a preferred embodiment, an elongated liquid-sensing probe having axially spaced electrodes adapted to sense liquid at multiple levels is arranged in each container of liquid. A controller, e.g. a suitably programmed microprocessor, operates to selectively poll different pairs of electrodes carried by the probe to determine whether or not the polled electrode pairs are immersed in the contained liquid. Preferably, the polling circuit comprises an electronically-controlled resistor that serves to normalize the level-sensing output signal for liquids of different bulk resistivity.

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