Abstract: Gripper apparatus on a sheet-processing machine includes a pair of cooperative gripper members, a control device including a computer for controlling the pair of gripper members, at least one data transmitter connected to the computer for inputting data therein, and at least one mechanism for performing at least one function selected from a group thereof consisting of opening and closing the pair of gripper members in response to an output of the computer, the function-performing mechanism being operatable at predetermined positions of the sheet-processing machine.

Abstract: A sheet-gripper device for sheet-fed rotary printing presses formed of a sheet gripper and a sheet-gripper seat, the sheet gripper comprising a sheet-gripper head and a gripper screw-on part, the sheet-gripper head being held by friction in the gripper screw-on part so as to be swivellable about a longitudinal axis of the sheet gripper.

Abstract: An electric or electronic sheet control device is provided at a sheet-transferring cylinder of a printing machine. According to the state of the art, in order to detect a leading edge of a sheet, two detecting elements respectively detect the presence of a sheet and a misaligned sheet. According to the invention, two detecting elements are disposed in such a way that they detect at least the outer areas of a leading edge of a sheet and at least one further detecting element is provided between the two detecting elements, which makes it possible to detect whether or not the leading edge of the sheet is straight.