Patent · US Expired

Optical-fiber liquid-level monitor

US5743135A · kind A · utility

30Cited by
17References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 10, 1995
Grant dateApr 28, 1998
Priority date
Expiry dateFeb 10, 2015

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S250/904
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A liquid level monitor uses a tube to confine a float to a vertical path with a canister containing a lower liquid and an upper liquid which meet at a liquid boundary, the level of which is to be monitored. Light from a light-emitting diode is conveyed to a vertical position of the tube by an optical fiber. A second optical fiber is arranged in a diametrically opposed position of the tube to detect light transmitted across the tube from the first optical fiber. The float is more transmissive than either liquid. When the level of the boundary falls to the level of the optical fibers, received light increases. The second optical fiber conveys this return light to a photodetector, the output of which can be used to trigger an alarm indicating that the boundary level is low.

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