Apparatus and method for sensing fluid level
US5656774A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 4, 1996 |
| Grant date | Aug 12, 1997 |
| Priority date | — |
| Expiry date | Jun 4, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01F23/284
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus (10) for sensing a surface level (24) of fluid (12) in a tank (14) having an electrically conducting pickup tube (20) extending through a wall (16) of the tank (14) and into the fluid (12) includes a time domain reflectometry circuit (40) connected to the tube (20) for generating an incident pulse (68) that travels down the tube (20) and a portion of which is reflected at the surface (24) as a reflected pulse (70, 72) which travels back along the tube (20) and is sensed by the circuit (40). The circuit (40) utilizes the elapsed time between the generation of the incident pulse (68) and the receipt of the reflected pulse to determine the position of the surface (24) relative to a reference point. The robe (20) forms a transmission line with one of a plate (48), an outer tube (110) and a return tube (130).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.