Abstract: A counter pressure cylinder including an electrostatic printing assist system, with the counter pressure cylinder including an insulating jacket having a conductive coating thereof over which a further coating is arranged having limited conductivity. A primary winding, concentric to an electrically grounded axle or shaft of the counter pressure cylinder, is disposed beside the counter pressure cylinder in a fixed fashion with respect to the printing unit, and a secondary winding is mounted concentrically to the electrically grounded shaft of the counter pressure cylinder at one end face of the counter pressure cylinder in a fixed fashion with respect to the counter pressure cylinder. An electrical connection of the secondary winding is connected to the axle of shaft of the counter pressure cylinder and another electrical connection is connected to the coating by way of a rectifier circuit.

Abstract: A dust removal arrangement for a turning bar in folders for printing machines has the turning bar surrounded by several suction chambers which, when viewed in cross-sectional, are arranged in a semicircular manner successively in parallel to the turning bar axis as well as in the moving direction of the paper, at least in the area of one of the lateral edges of the paper moving path. Discharge electrodes, has a d.c. voltage applied and are arranged at the paper inlet in the front area of the first suction chamber and at the paper outlet in the area behind the last suction chamber opposite the turning bar.

Abstract: A high voltage electrode device including a plurality of individual electrodes having end portions projecting beyond an insulating surface and arranged to form at least one group or electrically connected electrodes and apparatus for energizing and deenergizing each group of electrodes. The energizing and deenergizing apparatus includes a high voltage source associated with a respective group and having a control input for turning off the high voltage source wherein the high voltage source provides an output to the group via a current measuring device providing an output indicative of the current measured. A voltage measuring device is connected to the associated group and provides an output indicative of the voltage measured, and quotient forming unit responsive to the outputs of the current measuring device and the voltage measuring device forming a quotient thereof and providing an output when the quotient formed has a predetermined relation to a reference value.

Abstract: A method of folding a sheet, cut from at least one advancing web of material electrostatically bonded at least on one side and preferably consisting of paper or of a composite manufactured therefrom, transferred to a collecting cylinder, picked up in the vicinity of its midline by a folding cylinder that rests against the collecting cylinder in a nip along the midline of the sheet, and drawn completely over the folding cylinder while both halves of the sheet are folded together along the midline as the rotation continues, whereby the cylinders rotate in opposite directions and the web is charged at least outside the cylinders if necessary. An electrostatic field exerts a force of attraction in the nip (which is upstream in the direction that the two cylinders rotate in) on the top of the sheet (which is pulled off in a direction opposite the one that the collecting cylinder rotates in) toward a guide and the sheet is accordingly attracted and transferred to the folding cylinder.

Abstract: A probe is employed for removing dust from moving webs, paper webs for example. It has at least one electrostatic high-voltage electrode, at least one blower for gas, preferably air, oriented against the direction that the web travels in, and a vacuum channel for suctioning up the dust-laden gas. The pointed or blade-shaped subsidiary electrodes in the high-voltage electrode (10) lie in a plane that does not parallel the web (7). The direction that the row of round and/or slotted nozzles (12) in the blower (11) blow along lies in another plane downstream of the high-voltage electrode (10). The two planes intersect at a line that lies in the plane of the web (7) and extends across it. The round and/or slotted openings (14) into the vacuum channel (13) are on the other hand positioned upstream of the high-voltage electrode (10) in the web-travel direction (8).

Abstract: The air humidifier has a blower (2), the current of air that is generated by which is blown through a plate (3) with a medium that is permeable to air and that releases moisture in order to humidify the air. An electrostatically negatively charged high-voltage electrode (5) is positioned upstream and another (4) downstream of the plate (3).