Patent · US Expired

Liquid level sensor

US4082930A · kind A · utility

7Cited by
2References
3Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 23, 1976
Grant dateApr 4, 1978
Priority date
Expiry dateFeb 23, 1996

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01H36/02
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A liquid reservoir such as that for a brake master cylinder has a float in the liquid, a magnet and a reed switch secured to the float at a fixed spacing so that normally at high liquid level the reed switch is in a given state. When the liquid level falls, the float approaches a body of magnetic material suspended at a desired level in the reservoir or the bottom of the reservoir which comprises magnetic material. When low liquid level is reached, the body of magnetic material alters the flux field from the magnet to either increase or decrease the influence the magnet on the reed switch to cause a change of state of the reed switch thereby indicating low liquid level.

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