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. 28, 1993
Filed:
Apr. 28, 1992
David A Johnson, Fallbrook, CA (US);
Scott W Hock, San Diego, CA (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
The effects of heating on a printhead (16) used in a thermal ink-jet printer (10) provided with a heating means (30) to assist in drying ink on a print medium (12) are compensated for by making adjustments in the geometry, or architecture, of the printhead. Specifically, the dimensions of two portions of the structure for a cyan printhead are adjusted to provide more fluidic drag, first, by increasing the channel damping, and second, by increasing the shelf damping. The channel damping is increased by altering the dimensions of the ink-feed channel (48) leading towards the nozzle (42)/resistor (44) area, or firing chamber (50), specifically, by both lengthening and narrowing the ink feed channel. The shelf damping is increased by increasing that portion (52) between the edge (54a) of the ink refill slot (54) and the entrance to the ink feed channel. This increase in shelf length is most easily achieved by decreasing the width of the associated ink refill slot.