Sheet feed drum for rotary presses

摘要

A sheet feed drum for transferring sheets in a rotary printing press wherein the drum other contour is provided with an ink-repellent coating and two circumferentially spaced front and rear drum edges defining a duct therebetween which accommodates a sheet gripper system. The ink-repellent coating supporting a netting-like fabric relatively loosely thereon prevents any smearing of a freshly printed underside of a sheet during sheet feed on the drum while the sheet is engaged by the gripper system. Starting at the front edge of the drum, the outer contour of the drum is constructed in the form of a continuously increasing signal merging into a fixed drum radius whereby the netting-like fabric is contactable by the freshly printed underside of the sheet on the sprial first substantially flatly behind the front edge of the drum and then in any subsequent angle of rotation of the drum without the sheet tangent ever being bent or creased.