Patent · US Expired

Search head for metal detectors

US4959636A · kind A · utility

2Cited by
6References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 15, 1988
Grant dateSep 25, 1990
Priority date
Expiry dateDec 15, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01V3/107
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A search head for a metal detector, the head comprising a support body and three conductive loops mounted on the body, the loops being formed from a single ribbon cable. An oscillating signal is applied to one of the loops and induced voltages in the other two loops are subtracted, the arrangement being such that a difference will appear in the subtracted voltages when a metal object is closer to the other two loops.

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