DEVICE FOR SECTIONAL MONITORING BY TECHNICAL MEASURING INSTRUMENTS THE CONTROL OF HUMIDIFYING AGENTS WITHIN THE INKING SYSTEM OF AN OFFSET PRINTING MACHINE

摘要

- Abstract -The device for sectional monitoring by technical measu-ring instruments the control of humidifying agents withinthe inking system of an offset printing machine comprisesa measuring drum (3) adjusted to a printing paste feedingroller (1) and comprising a partly oleophile, partly hydro-phile surface. In order to precisely establish the partialvariations of the humidifying agent contents of the prin-ting paste across the full width of the machine, at leastthe oleophile surface areas are designed as screens (4)which guarantees both in longitudinal and in circumferen-tial direction of the measuring drum (3) A uniform zonalcoverage of an optional zonal coverage degree. During theprinting process, the oleophile screen (4) takes up prin-ting paste, whereas the hydrophile surface areas (5) re-main free from printing paste. An opto-electronical measu-ring device (6) is used to continuously measure the zonalcoverage and/or its variation on the oleophile screen (4),the measuring results being either shown on a subsequentindicating device (9) or directly used for an immediateapproach to zonal positioning elements of a humidifyingsystem. For the purpose of increasing the measuring sen-sitivity, the oleophile screen (4) can either present,in circumferential direction of the measuring drum (3),a uniformely graded surface coverage with at least twodifferent surface coverage degress or be preferently de-signed as a continuously proceeding screen wedge (10),providing for a continuous decrease from 100% to 0% ofthe surface coverage (see figure 1).