a b respectively the ink receiving roller 1 in radial direction the upper plate 4 which is radially longer than the lower plate 5 is pressed by springs 6 for example two springs fig3 with its front edge a essentially radially against the ink receiving roller 1 springs 6 are supported with one one end in the lower ink trough portion 3 and with its other end on a bolt 7 secured to the plate 4 one or more attachment screws 8 attaches the plate 4 to the lower portion 3 of the ink trough insuring that the plate 4 can move only radially with respect to the roller 1 the plate 4 is laterally retained by the respective screws 8 elongated or oval holes 7 permit radial movement while providing for longitudinal guidance the plate 5 is somewhat shorter radially than the plate 4 and its front edge b is also resiliently essentially radially engaged with the ink receiving roller 1 two springs 9 are provided for each plate 5 which are supported with one end in the lower ink trough portion 3 and with the other end on support bolts 10 secured to the respective plates 5 see fig2 as best seen in fig2 each of the plates 5 has an elongated or oval shaped hole 19 therein which is engaged by an eccenter 11 the eccenter 11 is adjusted by means of a gearing 12 which can.