Bi-directional dot matrix printer with slant control
AssigneeInternational Business Machines Corporation
InventorsLouis Valentine Galetto, Johann Hans Meier, Walter Thornton Pimbley, Bruce Allen Wolfe
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Abstract
A dot matrix printer apparatus has a magnetic ink jet recording head which projects a continuous stream of ferro-fluid ink drops toward a print medium. The ink drops are rastered in the direction orthogonal to the direction of relative motion of the recording head and the print medium to form characters from columns of dots. The slant of the characters caused by the change in direction of relative motion is controlled by reversing the direction or sequence of rastering of ink drops when the direction of printing reverses.
Claims14
An ink jet printer apparatus comprising print head including means for projecting a constant stream of field controllable ink drops toward a print medium;
- means for effecting continual relative motion of said print head and said print medium,
- said motion occuring first in one direction and then in an opposite second direction;
- means for controlling printing of characters by said print head on successive print lines when printing in both said first and second directions of motion comprising
- deflection means included in said print head for deflecting ink drops of said stream in a direction orthogonal to said direction of relative motion to produce columns of dots forming matrix characters recorded on said print medium, and
- slant control means for correcting for slanting of said characters due to deflection of said ink drops during said relative motion in both said first and second directions, including
- direction determining means for indicating direction of said relative motion, and
- means responsive to direction reversal indications from said direction determining means for effecting a reversal in the sequence in which said ink drops are deflected by said deflection means in said orthogonal direction in correspondence with reversals in the direction of said relative motion.
A dot matrix printer apparatus capable of bi-directionally printing successive lines of characters using relative motion between a print medium and a print means,
- said print means comprising means for sequentially recording a line of dots orthogonal to the direction of said bi-directional motion,
- means for controlling the operation of said print means for recording characters in the form of a plurality of said lines of dots during said bi-directional relative motion including
- slant correction means for correcting for slanting of said lines of dots due to said relative motion in both directions including,
- direction determining means for indicating the direction of said relative motion during said recording of said lines of dots, and
- means responsive to direction indications from said direction determining means for reversing the sequence for recording dots to form lines of dots in correspondence with reversals in the direction of said relative motion.
Dependencies are inferred from the claim text.