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. 10, 1996
Filed:
Oct. 06, 1994
Michael E Stamer, Lincolnwood, IL (US);
Colin Sharpe, South Elgin, IL (US);
Videojet Systems International, Inc., Niles, IL (US);
Abstract
The ink level sensor of the invention comprises an ink container having a generally cylindrical shield extending downward from its top to define shielded and unshielded compartments within the container. Ink, but not foam, froth or mist, flows under the shield to the shielded compartment. A plurality of conductive rods of differing length extend downwardly into the shielded compartment from the container top. The rods are connected to an impedance network which provides signals representative of the ink level inside the container. A vacuum source can be connected to each compartment to maintain pressure equilibrium in the compartments and to prevent foam, froth or mist from entering the shielded compartment. Alternatively, a return pump is used to force ink into the container such that each compartment can be vented to the atmosphere.