The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 06, 2001
Filed:
Jun. 25, 1998
Marie-Hélène Froger, Chateaugiron, FR;
Pascal Coudray, La Chapelle des Fougeretz, FR;
Mickaël Lorgeoux, Rennes, FR;
Canon Kabushiki Kaisha, Tokyo, JP;
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.