| 摘要 |
A rotary printing press having first and second cylinders in rolling engagement, the first cylinder being rigid and the second cylinder being resiliently covered, both of the cylinders having a longitudinal groove defining a gap in the cylinder surface, the gaps being rotated in opposed synchronism with one another. The groove in the first cylinder defines leading and trailing end walls with the end walls terminating at lips at the cylinder surface, the lips on the end walls each having bead projections which extend longitudinally therealong and which project a small distance outwardly from the nominal radius dimension of the cylinder thereby causing the lip on the leading end wall of the first cylinder to engage the surface of the second cylinder earlier than it would in the absence of a bead and causing the lip on the trailing end wall to separate from the surface of the second cylinder later than it would in the absence of the bead thereby to extend the pressure build-up and pressure drop-off angles between the cylinders and to cause a more gradual build-up of pressure between them to the operating level as well as a more gradual decrease from the operating level. |
