Eastman-kodak Company

Heidelberger Druckmaschinen Ag

Volker Otto

Rolf Spilz

Thomas Jacobsen

Dimitrios Kostudis

Stefan Schlünss

Rolf Johannes Spilz

V Jörg Leyser

Sheet inverters and methods for inverting sheets are provided that guide longer length receivers through a 180 degree turn while the receivers are being transported along a transport path while reducing the possibility of jams, the extent of sheet stress experienced during inversion and reducing the risk of creating print artifacts.

Sheet inverter and method for inverting a sheet

The invention relates to a method for the alignment of a sheet in a direction transverse (cross-track) to its transport direction in a sheet-printing machine, in particular in a digital printing machine, preferably in an electrographically operating printing machine. The object of the invention is to improve, in a simple manner, a method and a device of the aforementioned generic types in view of a first rough alignment of the individual sheet. Referring to the method, this object is achieved in accordance with the invention in that the individual sheet is flipped about a preferably non-physical, mathematical or imagined flipping axis extending in transport direction, and that this flipping produces a transverse offset of the sheet in transverse direction.

Method and device for the alignment of a sheet

Color register and/or register errors are detected in a printing machine by using triangles serving as register marks. A first triangle is printed onto a sheet near the leading edge and a second triangle is printed onto a sheet near its trailing edge. The first triangle and the second triangle are detected by a sensor and a displacement of the sheet at right angles to the travel direction of the sheet and/or an angular displacement of the sheet is/are determined.

Method of determining color register and/or register errors in a printing machine

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Gettorf, Germany

Volker Otto