overforingstrumma for tryckmaskiner instellbar for variable arklengd

摘要

A printing machine sheet transfer drum adjustable to variable sheet lengths has sheet carriers forming respective meshing comb-like structures adjustable relative to one another, and devices for gripping the leading and trailing edges of a sheet. The gripping devices are disposed in channels of the transfer drum and secured to the sheet carriers, the gripping devices having at least one continuous sheet-supporting rail extending from side to side of the sheet transfer drum. The transfer drum has a rigid main drum body integral with one of the comb-like structures and formed of at most two separable parts including the device for gripping the leading edge of the sheet, and a hollow, substantially cylindrical body partly surrounding the main drum body in circumferential direction thereof. The device for gripping the trailing edge of the sheet being disposed on the hollow body and forming therewith a rotatable sheet carrier unit.