Abstract: A computer controlled sheet-fed offset printing machine is described which includes an Interpreter-program for obtaining an image of the signal-state of specified interfaces of the many interfaces that are needed for the operation of the computerized printing press. The Interpreter-program has access to a reserved region of memory for storing and manipulating, if desired, the image of the signal-state. Furthermore, the Interpreter-program has very limited and defined access to the inputs and resources used by the control programs used to operate the computerized printing press. This ensures that the control programs can execute in real-time unaffected by the execution of the Interpreter-program while data is acquired by the Interpreter-program while the computerized printing press is in operation. The Interpreter-program can execute diagnostic routines and provide data for detecting and correcting errors that are otherwise hard to localize in a complex system with complex software.

Abstract: A method and a system for signal transmission between two computers is described, wherein one of the computers is fixedly mounted and the other computer is mounted in a rotational element, such as a plate cylinder of a printing machine. The transmission channel includes a rotational transformer. The rotational transformer utilized to transmit the signals is of single channel design. Data collisions resulting from the simultaneous transmission of messages are avoided through detection by the computers. Accordingly, both computers simultaneously transmit the signals present on the transmission channel during the transmission of a message and compare them with the transmitted signals. If an inequality is determined, the transmission procedure is aborted and restarted after a predetermined period of time.

Abstract: A method and an apparatus for controlling the sheet supply in a sheet-processing printing machine, in particular a sheet-fed offset printing machine. In order that, at the beginning of printing, before which a specific process for predamping and/or preinking the plate and/or blanket cylinders takes place, a first sheet always runs into the printing zone precisely on completion of the process, provision is made for a first sheet to be conveyed by means of the engagement and renewed disengagement of the feeder into a predetermined position from which the number of machine revolutions up to reaching the first printing zone is known. The feeder is disconnected and the separator and pull suckers remain pressurized, thereby continuing to hold a sheet gripped. The process for predamping and/or preinking is then started, whereupon the reengagement of the feeder takes place precisely at that moment after which a first sheet then runs into the first printing zone precisely on completion of the process sequence.

Abstract: A method for starting/restarting the production run on a sheet-processing printing machine in which the sheets to be printed are fed from a stack to the printing machine by a feeder assembly couplable to the printing machine and including separately actuable members causing removal of sheets from the stack, the method comprising the steps of: rotating the printing machine at a basic rotational speed; cutting in the feeder assembly; running-up the coupled printing machine and feeder assembly to a higher rotational speed, and cutting in the members causing removal of sheets from the stack to cause sheets to be conveyed into the printing machine.

Abstract: A method and a device for controlling the sheet inlet when starting up a sheet-processing printing machine having a vibrator-type inking unit, in which the sheets are positioned at front lays, their correct position is established and, in the case of the position having been established as correct, the sheet inlet is cleared at a particular machine position. The intention is to avoid the first entering sheet running into the printing machine in each case at different phases of the vibrator cycle in the case of a plurality of start-up operations. This is achieved according to the invention in that the first sheet is conveyed up to the positioning line, the feeder is then switched off and the sheet inlet is only cleared again when the vibrator gearing assumes a particular angular position.

Abstract: A throw-on and throw-off device for a blanket cylinder in the printing unit of an offset press is provided wherein two parallel double-acting fluid pressure cylinders connected to the blanket cylinder via a toggle-like linkage can be individually supplied with compressed air either consecutively or simultaneously so that, in the first case, precise sequential throw-on of the blanket cylinder on the plate cylinder and subsequently on the impression cylinder can be achieved and, in the latter case, there can be a very rapid throw-off of the blanket cylinder from both the impression cylinder and the plate cylinder. Compressed air energization of the two pressure cylinders is triggered by a control unit in accordance with the position of grip edge zones of the blanket, plate and impression cylinders being in registration.

Abstract: In a sheet-fed offset press having at least one printing unit in which the blanket cylinder can be thrown on and off the impression cylinder and plate cylinder by a pressure-medium-energized actuating arrangement, the pressure medium energization is triggered by a control unit in accordance with the position of grip edge zones of the cylinders being in registration. In order to ensure that throwing on and throwing off take place when the grip edge zones of the cylinders are positioned immediately opposite one another, the control unit detects the position of the printing unit cylinders relatively to one another by way of an angular position sensor and also detects the actual speed of the press via a speed sensor. The control unit forms speed-dependent throw-on and throw-off actuating times which are advanced in the direction of rotation of the printing unit cylinders so that the reaction time is outside the time slot for grip edge zone registration.