Printing apparatus with article driven text roll

Claim 1

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, which text roll can be driven by the passing surface, and a rotatable inking means for inking the coding characters, wherein the text roll is movable backwards and forwards in radial direction, and a driving means is provided for rotating the text roll and moving the text roll in radial direction from the 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, and in that 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, wherein the driving means operates a stop block movable backwards and forwards, said stop block having a first recess adapted to cooperate with a pin of the text roll, wherein the shaft of the text roll is borne in a bearing block movable backwards and forwards in the same direction as the stop block, said bearing block being movable by the stop block, wherein said stop block is adapted to rotate the text roll to the working position by means of the pin during the forward motion and to move the bearing block together with the text roll during the last part of the forward motion whereas the bearing block is returned by a return means during the first part of the backward motion of the stop block, the stop block further being coupled by a coupling member to the text roll for rotating the text roll to the rest position determined by said recess during the remaining part of the backward motion.