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:
Dec. 26, 2000
Filed:
Jun. 25, 1998
Marie-Helene Froger, Chateaugiron, FR;
Pascal Coudray, La Chapelle des Fougeretz, FR;
Mickael Lorgeoux, Rennes, FR;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
In order to monitor the state of a reservoir made of electrically insulating material containing a normally electrically conductive product, ink for example, the free end of the outlet channel of the reservoir is connected to a predetermined potential and two measurement procedures are defined, the first of which results in a first measurement signal, a characteristic of which varies mainly with the quantity of product contained in the storage cavity of the reservoir, and the second of which results in a second measurement signal, a characteristic of which varies mainly with the electrical conductivity of the channel between its ends. During the measurements, an abnormality correction procedure (or a simple alarm procedure) is triggered when the characteristic of the second measurement signal indicates a low electrical conductivity of the channel (absence of product) whilst the characteristic of the first signal indicates that there is still product in the storage cavity.