Apparatus for interface measurement in a storage tank
US5400651A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 1, 1994 |
| Grant date | Mar 28, 1995 |
| Priority date | — |
| Expiry date | Jun 1, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01F23/284
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus and method for measuring the water level at the bottom of a storage tank, the water level being the product-water interface between product and water within the storage tank. The apparatus includes a sensor assembly which is located at the tank bottom. The assembly has a plurality of measurement sensors arranged in a housing having slots for product and water to enter and leave the housing. Each measurement sensor is an open-circuited co-axial transmission line with a probe at its open end which functions as a monopole antenna. In preferred embodiments, the transmission lines are quarter wavelength open-circuited coaxial transmission lines. Each probe is located at a different distance from the tank bottom to cover a measurement range. The transmission lines are excited with signals which are reflected by the probes. As the level of the product-water interface changes on the probes, the capacitance of the probes also change which, in turn, change the amplitude or voltage level of the reflected signals. The voltage measurements are converted to level by a microprocessor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.