Device for measuring layer thickness in printing machines

摘要

The invention relates to a device for measuring layer thickness, in particular for the dynamic measurement of damping water layer thickness in printing presses. The aim of the invention is to provide a device for measuring layer thickness, which has a higher accuracy and thereby effects an increase in the quality of the printed products. The object of the invention is to configure the device in such a way as to compensate the effects such as contamination, aging phenomena and the like, which arise during the printing operation, on the part of the measuring device arranged upstream of the layer to be measured. The object is achieved by arranging a beam splitter in the beam path leading to the measurement location and assigning a first sensor to a part of the split beam and the measurement location to the second part of the beam, and by arranging downstream of the measurement location a sensor which detects the light reflected from the layer, as well as by connecting the sensor assigned to the first part of the beam to the light source via a control device which controls the brightness of the light source. <IMAGE>