Maschinenfabrik Wifag

Walter Siegl

Andreas Helfenstein

Olivier Stehlin

The present invention pertains to the register coordination of cylinders of a web-fed rotary printing press which print on a web, wherein a first cylinder printing on one side of the web is driven by a first motor and a second cylinder printing on the same side of the web is driven by a second motor. An angular position of the second cylinder is coordinated with the first cylinder in good register by a controller. In the case of a change in a production condition, at least one controller parameter (k , k , k , k ) of the controller is changed and the controller setting is adapted to the production condition as a result.

Good register coordination of printing cylinders in a web-fed rotary printing press

The present invention pertains to the coordination in good register of cylinders of a web-fed rotary printing press which print on a web, wherein a first cylinder printing on one side of the web is driven by a first motor and a second cylinder printing on the same side of the web is driven by a second motor and the angular position of the second cylinder is coordinated with the first cylinder in good register by a controller. At least one disturbance variable (v) is sent to a command variable (u ) for the motor controller of at least the second cylinder to compensate a register deviation (Y ) of the second cylinder from the first cylinder, which register deviation is typical of the said disturbance variable (v).

A control device for controlling the tension of a paper web of a printing press is provided with a setting device for a speed master set point, with a speed controller for a drive motor, which is coupled with the setting device, with a setting device for a web tension set point, with a sensor for measuring the web tension, with a web tension controller, which is coupled with the sensor for measuring the web tension and with the setting device for the web tension set point. The speed controller is coupled with an output of the web tension controller. A process is also provided for controlling the tension of a paper web of a printing press, wherein a speed master set point is preset, a web tension set point is preset, a first web tension actual value is measured, the difference between the web tension set point and the measured web tension actual value is formed; the difference formed is converted into a lag set point, and a variable, which is used to control the speed of rotation of the drive motor, is formed from the preset speed master set point and the lag set point.

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Bern, Switzerland

Walter Siegl