Patent · US Expired

Liquid level sensor

US4422328A · kind A · utility

11Cited by
8References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 13, 1981
Grant dateDec 27, 1983
Priority date
Expiry dateOct 13, 2001

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S73/05
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

The device senses the level of a float which may rest on the surface of the liquid whose level is to be determined or may rest on the surface of liquid (e.g., mercury) of a manometer which measures the level of liquid in accordance with the purge bubble principle. The fluctuation of the float turns a pulley which causes oscillatory movement of an arm carrying a magnet. In proximity to the path of the magnet is a board carrying radially disposed, angularly spaced reed switches. As the magnet passes each switch it closes same and passes a signal to a digital accumulator. A slip clutch between the arm and a second arm causes the latter to oscillate in the same direction as the first arm, but only for a limited distance. The second arm also carries a magnet which changes the direction of a second reed switch and dampens hunting of the first series of switches by preventing activation of the accumulator except when the second reed switch is closed.

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