Method and device for detecting the absence of a product in a reservoir
US6438500B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 26, 1998 |
| Grant date | Aug 20, 2002 |
| Priority date | — |
| Expiry date | Jun 26, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01F23/802
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
Detecting presence or absence of product in a reservoir by transmitting a signal affected by the product. The signal is detected from among other signals with which it is subsequently received by discrimination and delivery of an output signal whose level is set by the discrimination, and by sampling. Pairs of samples are correlated to obtain a true correlation value SR, where the instantaneous value of correlation between the state value B(i) and the state value B(i+Z) is summed, Z being the number of samples taken during a period T of the signal to be detected. A rate calculation is performed, during which the rate &rgr; of samples representing the presence of the signal is measured, and theoretical correlation mean values are evaluated. A decision is made by comparison of the true correlation value SR with each theoretical correlation mean value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.