Abstract: A printing apparatus for applying a coding on a surface which is transported past the printing apparatus, comprising a text roll for the coding characters, supported by a frame and rotatably mounted on a shaft. Said text roll is drivable by the passing surface. The printing apparatus further comprises a rotatable inking means for inking the coding characters. The text roll is movable backwards and forwards in radial direction, wherein a driving means is provided for rotating the text roll and moving the text roll in radial direction from a rest position, in which the text roll is completely free of the surface to be coded, to a working position, in which the text roll engages the surface to be coded, when a surface to be coded comes up to the text roll. The driving means is adapted to return the text roll in radial direction and to rotate the text roll to the rest position from an end position reached by the coding operation after applying the coding.