Method and device for detecting a filling threshold for an electrically insulating reservoir containing an electrically conductive product, for example a printing ink
US6185515A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 25, 1998 |
| Grant date | Feb 6, 2001 |
| Priority date | — |
| Expiry date | Jun 25, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01F23/266
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
The object of the invention is the detection of a given threshold (optionally zero) for filling, with an electrically conductive product, a reservoir made of electrically insulating material having a storage cavity connected to an outlet channel. An excitation signal is applied to the cavity, in periodic square waves, and a measurement signal is taken off, one characteristic of which varies substantially with the quantity of product contained in the cavity reaches the filling threshold. From this characteristic, by comparison with a reference threshold, a binary signal C,C' is derived, which is filtered digitally whilst multiplying it (convolution product) by a signal which is identical to it, but with a delay equal to a multiple, at least equal to one, of the period of the square waves.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.