Loading patent…
AssigneeHewlett-Packard Company
InventorsAntonio Murcia, Xavier Bruch, Chris Taylor, Xavier Girones, Lluís Vinals
Estimating the term…
It is first determined whether any printing element of a printhead has failed. If so, functions of the failed element are reassigned to other elements. Some aspects of the invention do this in such a way as to maintain essentially single-pass operation. Ordinarily the reassigned functions are applied to control operation of the head or heads, to print images on a print medium, and functions of the apparatus and method are effected automatically by program instructions—in nonvolatile memory. One approach to the reassignment includes removing from service all printing elements between the failed element and a nearer end of the head, inclusive—and then preferably operating all remaining in-service elements as a shorter printhead. If the printhead operates in conjunction with a print-medium advance mechanism, then also preferably each operation of that mechanism is shortened to correspond to a height of the shorter head. Another approach, if the failed element is in a black printhead and the printer has three or more subtractive-primary-color heads, includes assigning a corresponding printing element of each of those color heads, in combination, to print in lieu of the failed black-printing element. Yet another approach—if the printer has other heads that print the same color as the failed element—is assigning a corresponding element of one or more of those heads to stand in for the failed element. Still another approach includes assigning a printing element near (preferably next to) the failed element.
A method of printing desired images on a printing medium, by construction from individual marks formed by at least one scanning multiple-printing-element printhead that operates in substantially a single-pass mode of operation and without duplicate nozzles in tandem along a scanning direction;
A method of printing desired images on a printing medium, by construction from individual marks formed by at least one scanning multiple-printing-element printhead that operates in substantially a single-pass mode of operation;
Apparatus for printing desired images on a printing medium, by construction from individual marks formed by at least one scanning multiple-printing-element printhead, without duplicate nozzles in tandem along a scanning direction;
Apparatus for printing desired images on a printing medium, by construction from individual marks formed by at least one scanning multiple-printing-element printhead;
A method of printing desired images on a printing medium, by construction from individual marks formed by at least one scanning multiple-printing-element printhead;
A method of printing desired images on a printing medium, by construction from individual marks formed by at least one scanning multiple-printing-element printhead but no duplicate nozzle in tandem along a scanning direction;
Dependencies are inferred from the claim text.