Printer synchronization control for shuttle having non-uniform velocity

摘要

A printer synchronization control for maintaining columnar alignment of dots printed by a dot matrix printer including a shuttle wherein the relative velocity between the paper and shuttle is non-uniform. Plural print elements are mounted on the shuttle for printing dots at preselected positions on the paper. A particular row and column arrangement of the dots defines a character. A counter measures the relative velocity between the paper and shuttle over a period of time inversely proportional to the relative velocity. A second counter determines the time at which an actuator must be triggered to cause a print element to strike the paper at a preselected columnar position to maintain columnar alignment of the dots in a character. Means are provided for causing the print element to strike the paper at the preselected columnar position as a function of the second counter. A third counter may be provided to enable two or more sets of the print elements to be actuated in time-staggered fashion to minimize peak current drain.