Abstract: 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.

Abstract: A device for controlling substrate web tension includes first and second driving units with respective driving rollers around which the substrate web is partially guided and tensioned. The first and second driving units have different rotational moments of inertia. A measuring unit measures the tension of the substrate web. A control unit has first and a second filtering units with different filtering characteristics for filtering the measured value. The control unit includes a first control device for controlling the first driving unit based on the measured value filtered by the first filtering device, and a second control device for controlling the second driving unit based on the measured value filtered by the second filtering device.

Abstract: 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.

Abstract: A device for controlling substrate web tension includes first and second driving units with respective driving rollers around which the substrate web is partially guided and tensioned. The first and second driving units have different rotational moments of inertia. A measuring unit measures the tension of the substrate web. A control unit has first and a second filtering units with different filtering characteristics for filtering the measured value. The control unit includes a first control device for controlling the first driving unit based on the measured value filtered by the first filtering device, and a second control device for controlling the second driving unit based on the measured value filtered by the second filtering device.

Abstract: A method for feeding a plurality of sheets from a stack of sheets into a sheet processing machine includes picking up a first sheet from the stack of sheets using a first feeding device. The sheet is conveyed to a first transfer point of the processing machine. A second sheet is picked up from the stack of sheets using a second feeding device and conveyed to a second transfer point. The first and second transfer points are spatially separated. The sheets alternately move into a sheet conveyor device of the sheet processing machine. A single transfer point can also be used.

Abstract: Provided is a device for the alignment of sheets in a printing machine, said device comprising two pairs of rollers for the alignment of the sheets in their advance direction, for the alignment transverse to their advance direction and with respect to skewing, whereby each pair of rollers consists of a driving roller and of a counter-pressure roller. One drive unit is provided for each of the two driving rollers, whereby each of the drive units consists of a motor and a drive shaft linked therewith, whereby the driving rollers are non-torsionally accommodated on respective drive shafts. The driving rollers can be slid in linear direction on their drive shaft, or the respective drive shafts, and thus the driving rollers accommodated thereon, can be linearly shifted with respect to their drive motors.

Abstract: A method of printing an image onto a sheet in a printer having at least one print module and a transport arrangement defining a transport path for transporting sheets through the at least one print module is shown. In accordance with the method, a series of constant frame clock signals is generated and a sheet is approximately feed into a frame along the sheet transport path in accordance with the frame clock signal, wherein the frame defines a virtual desired sheet position, which moves with a predetermined speed along the sheet transport path. The sheet is transported along the sheet transport path, an in-track position of the sheet in the sheet transport path is detected and it is determined whether the in-track sheet position matches the frame within predetermined limits.

Abstract: Provided is a device (1) for the alignment of sheets in a printing machine, said device comprising two pairs of rollers for the alignment of the sheets in their advance direction, for the alignment transverse to their advance direction and with respect to skewing, whereby each pair of rollers consists of a driving roller (20a, 20b) and of a counter-pressure roller (22a, 22b). One drive unit (29, 32, 36, 38) is provided for each of the two driving rollers, whereby each of the drive units consists of a motor (38a, 38b) and a drive shaft (29a, 29b) linked therewith, whereby the driving rollers are non-torsionally accommodated on respective drive shafts. The driving rollers can be slid in linear direction on their drive shaft, or the respective drive shafts, and thus the driving rollers accommodated thereon, can be linearly shifted with respect to their drive motors.

Abstract: 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.

Abstract: A method and control device for determining a register error, whereby at least one register mark is printed and at least one sensor records the register mark, whereby the sheet edge of the sheet is recorded by the sensor, and the register error is determined from the sensor data and the target data.

Abstract: A cutting-register feedback-control device of a cross-cutter of a rotary printing press for printing on a printing-carrier web, the cross-cutter including a driven cutting cylinder, and the rotary printing press having printing-unit cylinders, drawing devices for the printing-carrier web and positioning devices for adjusting the position of the printing-carrier web, the cutting-register feedback-control device including scanners for scanning markings on the printing-unit cylinders and for scanning the driven cutting cylinder, the scanners being connected to comparison and control circuits operatively connected with the positioning devices for the printing-carrier web so as to effect a correction in a position of the printing-carrier web if there should be an angular deviation between the printing-unit cylinders and the driven cutting cylinder, also being provided are rotary-position sensors, respectively, for the printing-unit cylinders, the drawing devices and the cutting cylinder, and a first control loop f

Abstract: Method for setting the cutting register on a cross-cutting device positioned downline of a web-fed printing press, the position of the cut edges being variable as a function of the position of the printed image on a moving web, includes scanning with a first scanning device located directly after a last printing unit of the web-fed printing press a printed image on a moving web, generating and feeding signals regarding the printed image to a control device, generating signals with an angle sensor connected to web-guiding cylinders of the web-fed printing press, and associating the angle-sensor signals with the printed-image signals in a region between two printed images and storing the signals in the control device, generating signals regarding the printed image with a second scanning device directly before a cross-cutting device in the region between the two printed images, directing the scanning device, as viewed in a transverse direction of the web, at the same line as the first scanning device, periodical