SENSING DEVICE FOR INK FILM THICKNESS IN PRINTING PRESSES

摘要

SENSING DEVICE FOR INK FILM THICKNESS IN PRINTING PRESSES A device for detecting changes in ink film thickness on the inking rollers of a printing press which includes a transfer wheel rotatable mounted in nipping contact with one of the inking rollers. A rotatable guage wheel having a slinger ring assembled intermediate its ends and about its periphery defines a measuring surface on one side of the ring for receiving a film of ink from the transfer wheel and the other side defines a reference surface maintained clear of ink by the ring Individual photo-electric sensing members are tangentially associated with the peripheral surface of both the measuring and reference surfaces and by means of a cooperating circuit including a comparetor, a signal change is given when a difference in ratio occurs between pre-selected signals from these surfaces.