Microprocessor based apparatus and method for sensing fluid level
US5651286A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 23, 1996 |
| Grant date | Jul 29, 1997 |
| Priority date | — |
| Expiry date | Jul 23, 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) includes a microprocessor (92) which 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 and the amount of the fluid (12) in the tank (14) and indicate the amount of fluid at a display (106). The tube (20) forms a transmission line with one of a plate (48), an outer tube (110) and a return tube (130). A sensor (98) connected to the microprocessor (92) generates information representing parameters of the fluid (12) and the microprocessor (92) communicates over a bus line (94).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.