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. 03, 2004
Filed:
Aug. 07, 2002
Daniel D. Dowell, Albany, OR (US);
Louis Barinaga, Salem, OR (US);
James P. Kearns, Corvallis, OR (US);
Hewlett-Packard Development Company L.P., Houston, TX (US);
Abstract
Apparatus for providing ink to an ink jet print head. The apparatus includes a back pressure regulator for receiving ink from an ink reservoir and for delivering ink to the print head. The regulator has a compliant wall that responds to atmospheric pressure on one side and to the pressure of the ink in the regulator on the another side. Within the regulator is a valve that regulates the pressure of the ink delivered to the print head and is actuated by the wall. Also within the regulator is a compression spring that simultaneously pre-loads the valve shut and urges the compliant wall against the atmospheric pressure. In an other aspect, an apparatus is provided with a print head having two arrays of nozzles and two back pressure regulators that independently deliver inks of different hues to separate arrays of nozzles on the print head. In still a further aspect, the apparatus performs bi-directional ink jet color printing without hue shift through positioning the regulators and print heads with respect to the printer carriage.