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:
Aug. 11, 1998
Filed:
Aug. 05, 1996
Patrick J Coven, Albany, OR (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
An inkjet printhead includes multiple printing elements grouped in sets about an ink refill channel. Each printing element includes a firing chamber and resistive element in communication with the refill channel via an ink feed channel. The feed channels are of differing length resulting in resistive elements being at staggered distances from the refill channel. To balance fluidic dynamics among printing elements a first constriction and second constriction occur along the length of the feed channels. The first constriction is adjacent the firing chamber and acts as a diffuser during firing. The second constriction is adjacent the refill channel and slows the refill process for feed channels of shorter length. For longer feed channels the second constriction is wider. For shorter feed channels the second constriction is narrower. Differing widths of the second constriction slow down refill by differing amounts to balance fluid dynamics among the printing elements.