SHEET FEEDING UNIT FOR ROTARY PRINTING MACHINE

摘要

A sheet feeding unit for a rotary sheet printing machine which is operative for selective face printing or face and back printing with turning of a sheet rear edge and which has a turning cylinder and a printing cylinder located before the turning cylinder, includes elements located underneath the turning drum and the printing drum for conducting and guiding overlong sheets in face and back printing during a turning step on a front edge. The elements include a suction member arranged rotatably over a circular path so as to take over a sheet in a point of intersection of tangent ts, a stationary segment arch arranged equidistantly relative to the circular path under a point of intersection T4,5 of the printing cylinder and a sheet guiding cylinder and also provided with guiding rollers, and a guiding plate located above a turning point of the suction member at a distance from the printing cylinder and inside the circular path over a line of a secante.