| 摘要 |
1,124,736. Printing machines. MIEHLEGOSS-DEXTER Inc. 29 July, 1966 [13 Aug., 1965], No. 34114/66. Heading B6C. In a rotary printing press wherein the end edges of printing plates mounted on the plate cylinder 10 are spaced so as to leave a gutter, the surface of the impression cylinder is shaped so that a gradual decrease and increase of pressure between the cylinders occurs in the vicinity of the gutter thus obviating streaks in the printing caused by sudden variations in pressure when the gutter reaches the printing position. In one embodiment, the impression cylinder 30 is cut away at the shaded area 57 Fig. 2a, which includes the part normally engaging the gutter. The area extends beyond the gutter so as to gradually reduce the pressure between the cylinders gradually as the gutter approaches the printing position and to increase the pressure gradually as the gutter leaves the printing position but maintains a printing pressure between the plates and the impression cylinder up to the edges of the plates. In a modification, a metal underlay is provided between the impression cylinder blanket and the cylinder and is cut away as described above in the area where it would be opposite to the gap. The ends of the plates may be secured by devices mounted in the gutter, or the gutter may be a groove in the plate situated between parts of the plate printing separate pages. |
