Tube blockage monitor
US6661514B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 17, 2000 |
| Grant date | Dec 9, 2003 |
| Priority date | — |
| Expiry date | Feb 17, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2015/1418
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A blockage monitor for detecting a blockage in flow of particles includes a sensor body for mounting on a wall of the seed duct and defining a front face flush with the duct surface carrying both an LED light source for projecting light into the interior of the duct and a phototransistor arranged to produce an output signal proportional to the intensity of reflected light received which increases as a seed passes. A separate blockage module counts the output and uses an algorithm for comparing the count with a calibration count to determine whether there is a blockage of the duct. A power voltage is supplied to each sensor using two wires. A test of the sensor includes a pulse in the power voltage so as to generate a corresponding but delayed pulse in the light from the light source.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.