RAM vent capacitance level probe with overfill leak detection capabilities
US5397995A · kind A · utility
Inventor
Key dates
| Filing date | Apr 21, 1993 |
| Grant date | Mar 14, 1995 |
| Priority date | — |
| Expiry date | Apr 21, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01F23/263
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An improved capacitance level probe is shown which can be positioned within the return vapor passage of a coaxial vapor recovery refueling system for detecting changes in liquid level within an underground fuel storage tank. The level probe has an outer conductor, a spaced inner conductor, a closed upper end and a lower end with an end opening which allows liquid to enter and leave the interior of the probe as liquid level changes within the underground tank being monitored. A tubular impact vent is located at the upper end of the outer conductor and collects tank vapors from the return vapor passage in order to conduct such vapor pressure to the open interior of the outer conductor above the level of liquid within the outer conductor. This action prevents sudden pressure drops within the outer conductor as the level of fuel changes within the underground storage tank, thereby eliminating inaccuracies in the sensed capacitance of the unit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.