David Kent Holcomb

US Patent:

47400927, Apr 26, 1988

Filed:

Jul 14, 1986

Appl. No.:

6/885356

Inventors:

Steven L. Applegate - Lexington KY
John C. Bartlett - Lexington KY
Brian W. Damon - Lexington KY
David W. Holcomb - Lexington KY
Cary P. Ravitz - Lexington KY

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

B41J 312

US Classification:

400 53

Abstract:

Wear on the elements (5) of a printhead (3) is spread by shifting the region of use of the printhead line by line. Font (13) provides information as to whether any character in a line employs the upper three pels or the bottom three pels of a line. For each line which can be printed from different shift positions of the printhead, selection logic controls paper feed (15) to index platen (9) to the least used of a shifted position of printhead. Only those electrodes over the print line in each shifted position are used for printing. This distributes wear without requiring any special ribbon feed. The three pel height is at least as wide as the serifs on most characters, which avoids some electrodes being used for the serifs of given characters in more than one shift position.