Non-fouling liquid level control
US6557412B1 · kind B1 · utility
Inventors
Key dates
| Filing date | Sep 24, 2001 |
| Grant date | May 6, 2003 |
| Priority date | — |
| Expiry date | Oct 1, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01F23/76
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A non-fouling liquid level detector and control especially for a sealed system likely to have iron particle contaminants. The device employs a float projecting above the liquid level and bearing above the liquid level a unmagnetized ferromagnetic tell-tale. A magnetic field is generated by a magnet positioned outside the sealed system. The magnetic field extends around the float and tell-tale through a magnetically permeable partition comprising a wall of the sealed system that is positioned between the magnet and the float. The float position is monitored by a magnetic field sensor such as a Hall Effect device positioned adjacent the magnet, outside the sealed system. The sensor responds to the movement of the tell-tale. The output of the sensor is employed to control the monitored liquid level.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.