Roland Offsetmaschinenfabrik Faber & Schleicher Ag

Klaus List

Paul Abendroth

A dampening system for a lithographic printing press which includes, in series, a driven fountain roller, an adjustable intermediate roller, a driven distributor roller, and an adjustable form roller, the latter engaging the printing plate, the intermediate and form rollers being mounted upon respective throw-off levers. A single actuator is used, connected to the form roller throw-off lever. The intermediate roller throw-off lever is effectively in the path of final movement of the form roller throw-off lever, for throw-off by the latter, so that upon subsequent restoration to working position a water path is completed progressively through all of the rollers starting with the fountain roller, and with the form roller touching the plate last, thereby to insure, regardless of the length of the period of throw-off, that the form roller will be wetted to proper degree, free of either flooding or starvation, before being applied to the plate. It is one of the features of the invention that the reaction force of the intermediate throw-off lever against the form roller throw-off lever, upon throw-off, acts through the center of rocking movement of the latter so that the actuator does not have to resist the reaction force. In the preferred form of the invention pressureless 'kissing' contact is retained between the intermediate roller and the fountain roller and between the distributor roller and the form roller under the condition of throw-off to insure that the residual moisture on the surfaces of the latter does not contract into droplets.

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Wachtersbach, Germany

Klaus List