Patent · US Expired

Apparatus for detecting conductive liquid level

US4125021A · kind A · utility

11Cited by
6References
13Claims
0Family size

Assignees

Inventors

Key dates

Filing dateJun 1, 1976
Grant dateNov 14, 1978
Priority date
Expiry dateJun 1, 1996

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01F23/26
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An apparatus for detection of the level of a liquid metal is disclosed. The apparatus has a liquid level detecting probe provided with an exciting coil wound in a closed bottom non-magnetic sheath over the approximately whole length thereof, a level detecting coil wound in the sheath in an upper part thereof, and a temperature compensating coil wound in the sheath in a lower part thereof; a temperature control for maintaining the coils at a constant temperature; a drive circuit for supplying the exciting coil with an alternating current of a determined frequency and amplitude; and a signal processing circuit for subjecting output voltages induced in the liquid level detecting coil and in the temperature compensating coil to linear detection and then determining the ratio of the thus detected outputs, thereby detecting the level of the liquid metal. At the time of operation, the liquid level detecting probe is immersed in the liquid metal the level of which is to be detected in such a manner that the temperature compensating coil is always located below the level of the liquid metal.

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