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:
Sep. 10, 2002
Filed:
Mar. 13, 2001
Ronald W. Keil, Carvallis, OR (US);
Donald W Schulte, Carvallis, OR (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
A firing chamber configuration for the drop ejectors of inkjet printheads extends the life of the heat transducer by ensuring that bubble collapse (and attendant cavitation) occurs at a location well spaced from the heat transducer. The sidewalls of the firing chamber are shaped relative to the firing chamber entry in a manner such that a strong jet of inflow ink is provided for moving the collapsing vapor bubble from the center of the chamber and against a curved back wall of the firing chamber. In one preferred embodiment, the refill ink impinges on the back wall, divides, and is redirected away from the back wall toward pockets defined in chamber. The pockets are remote from the heat transducer. As a result, the refill ink urges the collapsing (bifurcated) bubble into the pockets where final collapse occurs away from the heat transducer.