Equipment for printing on both sides of continuous paper feed, has printing drums on either side of vertical section of paper run and time delay unit between front side and rear side control units

摘要

Front side (3) and rear side (4) printing units are located on opposite sides of a vertical section of paper (P) feed and include photosensitive drums (37,47), photoemissive heads (31,41) and developing units (32,42). Print control units govern the photoemissive heads (31,41). A time delay unit, which may be a counter, delays the line signal to the rear side control unit and head, to allow for the time taken by the paper to cover the distance (L) between printers