Abstract: A printing material is provided for control of a printing operation and for following the path of a printing material from manufacturing until recycling. The printing material is provided for a printing machine, whereby in the printing machine, data saved in the printing material is read and the read data is used in order to control the printing machine so that the settings of the printing machine are adapted to the printing material. The data is located in a thin elastic microchip, which is completely embedded in the printing material and does not impair the application of toner onto the surface of the printing material and the printing operation. The data of the microchip is read up to a distance of several meters in a non-contact manner.

Abstract: Detecting a transparent object, in particular a web or conveyor belt of a printing press with at least one radiation source and at least one receiver arrangement for receiving rays from the radiation source, whereby the light intensity change based on the transparent object is independent of the position of the major optical axis h of the transparent object. A particular embodiment envisages two &lgr;/4 small plates, which are each attached to one of two linear polarization filters, which intersect one another.

Abstract: A method and device for detecting a more opaque area or object in comparison with a translucent area or object, preferably for the detection of a stock or substrate on a transparent conveyor belt, by a light barrier. Reflection losses are preferably prevented, so that the light of the light barrier, which shines at least approximately under the Brewster (polarizing) angle on the translucent area or object, is used.

Abstract: To determine the thickness of a liquid layer, particularly that of an oil film, on a roller in a simple manner that saves time and that is cost-effective. To achieve this task, a procedure and a device are provided in which the thickness of the liquid layer is measured by a measuring device in the printing press. In addition, a delivery device for liquid is controlled on the basis of the measured thickness of the liquid layer.

Abstract: A procedure and device for measuring the thickness of a liquid layer, in particular an oil layer, on the rollers of printing presses. The mass of the liquid layer in the printing press is measured by a measuring device and that the thickness of the liquid layer on the roller be determined on the basis of the measured mass of the liquid layer. The measuring device preferably contains a piezoelectric sensor in a quartz microbalance, which picks up the frequency changes on the basis of the mass applied to the surface or on the basis of changes in the mass and converts them into corresponding masses or mass changes on the basis of the liquid layer. Furthermore, a control device is provided which controls the application of fluid on the roller as a function of the masses or mass changes determined.

Abstract: A hydraulic control arrangement with a feedback device for positioning an implement comprises a positioner including a fluid operated cylinder and piston unit, the piston of which is connected by a plurality of linkage elements to the implement. A first pump delivers through a pressure line fluid under pressure into the cylinder. A two-port three-position valve is interposed in the pressure line movable from a neutral position in which the fluid fed by the first pump is directed to a reservoir, to two operating positions to opposite sides of the neutral position, and in which one of the operating positions fluid fed by the first pump passes into the cylinder and in the other of the operating positions fluid from the cylinder can flow to the reservoir. A pair of pilot chambers are arranged at opposite ends of the valve for moving the latter from the neutral to either of the working positions. A second pump provides fluid under pressure for operating the valve.