Device for dosing the supply of a flue sig to plate cylinder of a printing press, for example for dosing the supply of moist flue sig to plate cylinder of an offset - printing press

摘要

Arrangement for dosing the supply of a liquid, in particular damping solution or ink, to the printing plate cylinder of an offset printing press. Damping solution is conventionally supplied to the printing plate cylinder of an offset printing press either by film damping systems without ductors or by spray damping systems. The film damping systems do not permit selective, variable adjustment of the supply of solution to relatively narrow areas; in the case of spray damping systems, the image of the jet is often visible on the printed image. An adjustable supply of ink to individual areas is obtained using rollers subdivided into separately adjustable partial rollers. These damping systems are expensive andprone to failure. The new arrangement is simple and reliable and ensures a uniform, easily reproducible supply of damping solution or ink, even in small quantities and different from one area to another, to the printing plate cylinder. This is achieved by the use of a roller with an elastic casing, the diameter of which can be varied from inside the roller by a fluid or gaseous hydraulic medium supplied in a controlled manner from the exterior.