Patent · US Expired

In-situ measurement system

US4420974A · kind A · utility

7Cited by
22References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 24, 1980
Grant dateDec 20, 1983
Priority date
Expiry dateNov 24, 2000

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01P5/12
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A multipurpose in situ underground measurement system comprising a plurality of long electrical resistance elements in the form of rigid reinforcing bars, each having an open loop "hairpin" configuration of shorter length than the other resistance elements. The resistance elements are arranged in pairs in a unitized structure, and grouted in place in the underground volume. The electrical resistance of each element and the difference in electrical resistance of the paired elements are obtained, which difference values may be used in analytical methods involving resistance as a function of temperature. A scanner sequentially connects the resistance-measuring apparatus to each individual pair of elements. A source of heating current is also selectively connectable for heating the elements to an initial predetermined temperature prior to electrical resistance measurements when used as an anemometer.

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