Patent · US Expired

Method for near field electromagnetic proximity determination for guidance of a borehole drill

US5923170A · kind A · utility

247Cited by
4References
21Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 26, 1998
Grant dateJul 13, 1999
Priority date
Expiry dateMar 26, 2018

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01V3/28
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A method and apparatus for precise measurement of the distance and direction from a magnetic field sensor to a nearby magnetic field source includes an elongated iron core solenoid driven by a repetitive, nonsinusoidal current source. In the near field the solenoid has two spaced, temporally varying magnetic poles, and measurement of the distance and direction to this source includes analysis of field components which vary in synchronism with the current source.

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