| 摘要 |
A web-fed, multicolor, offset perfecting printing press having a stack of printing units each having a combination of a plate cylinder and a blanket cylinder on one side of a continuous web of paper, and another such combination on the other side. Each plate cylinder is split into a pair of halves for printing a pair of images in juxtaposition transversely of the web. For precise registration of the different color images printed by the different printing units on the web, there are provided a pair of axial adjustments coupled to opposite ends of each plate cylinder for causing axial displacement of the respective plate cylinder halves with a view to fine image positioning transversely of the web, and a circumferential adjustment for causing circumferential displacement of either half of each plate cylinder with a view to fine image positioning longitudinally of the web. A separate drive mechanism drives each combination of one plate cylinder and one blanket cylinder, so that each drive mechanism serves the additional purpose of positioning the images longitudinally of the web preparatory to fine positioning.
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