Patent · US Expired

Material level detector and control

US4589281A · kind A · utility

26Cited by
30References
43Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 20, 1984
Grant dateMay 20, 1986
Priority date
Expiry dateSep 20, 2004

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01F23/22
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Disclosed is a monitoring system and method for detecting the presence or absence of material at a location. The apparatus may generally be constructed to include a sensing unit, including an antenna probe for positioning at the location wherein material is to be detected, and a control unit for responding to signals from the sensing unit indicating the presence of material at the antenna probe. The control unit may include an indicator to inform an operator of the presence or absence of material at the antenna probe, and also an output which enables peripheral equipment to operate only under selected conditions at the antenna probe. The sensing signal from the sensing unit is dc, with fluctuations indicating the presence of material at the antenna probe. The sensing signal may be communicated a considerable distance to the control unit over ordinary electrical lead lines without electrical shielding, and the control unit responds to a break in such communication lines by not permitting enabling of such peripheral equipment.

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