Patent · US Expired

Electronic marker for metallic valve box covers

US6690278B2 · kind B2 · utility

3Cited by
23References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 28, 2001
Grant dateFeb 10, 2004
Priority date
Expiry dateJan 24, 2022

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06K19/07749
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A valve box having a metallic riser and a metallic lid covering a top of the metallic riser and an electromagnetic resonator coupled to the valve box interior facing side of the metallic lid, whereby, upon generation of an eddy current in the metallic lid, a current is generated in the electromagnetic resonator. This valve box, when buried, is readily locatable and identifiable by an above-ground interrogating device.

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