摘要 |
Print smearing observed in double wide hammers can be controlled and reduced by providing the impact face of the print hammer with a concave cylindrical radius of curvature wherein the cylindrical axis is parallel to the vertical font direction. The radius of curvature is chosen according to impact energy and font velocities. In other embodiments, the timing of impact between the hammer and font characters may be offset such that the center of the print column leads the center of the impact hammer at the time of impact. In another embodiment, the radius of cylindrical curvature may be ground off center from the center line of the print hammer by a predetermined offset.
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