Programme-controlled supply of ink to four-colour sheet printer

摘要

The gradient of a colour change is determined over a number (n1) of prints by means of a controller or regulator which processes signals from an image sensor. The measured value is compared with a set-point represented by a curve (2) within a tolerance band (3) memorised before the commencement of printing.The number of prints required for attainment of the desired deg. of inking (DSOLL) is counted and compared with a desired number. The discrepancy is used to adjust the amt. and duration of oversetting of the ink feed elements.