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 process and mechanism to scan at least one register mark on a printing medium in a printing machine, whereby at least one register mark is imprinted on the first form side of the printing medium and the register mark is scanned by an initial sensor, whereby when the printing medium is inverted, the register mark on the first form side is scanned, and the register mark on the reverse side is ascertained using the register mark on the first form side.

Abstract: The invention relates to a device for detecting the location of an edge (2) of a transparent, anisotropic material (3,3′) comprising at least one sensor (1) with a light source (4), two polarization filters (6,7) with transmission axes (8,9) meeting at a 90° angle as well as a light detector (10), whereby the light source (4) and one polarization filter (6) are located on one side of the edge (2) to be detected and the second polarization filter (7) and the light detector are located on the other side. This type of device is to be configured in such a way that it can be used for detecting material (3,3′) with optical axes (14) in various directions without requiring assembly. This is achieved by at least one of the sensors (1) being configured and/or adjustable so that various angles (32) between the transmission axis of the first polarization filter (6) and the optical axis (14) of the transparent, anisotropic material (3,3′) are possible.

Abstract: The invention relates to a process and a device for alignment of sheet material (1) which is conveyed in one conveyor plane (9). The sheet material is conveyed on bodies (35) of revolution and aligned by means of triggerable alignment elements (25) in the conveyor direction (22) and perpendicular to the conveyor direction (22). The alignment elements (25) are assigned to an alignment unit (8). The alignment motion necessary for alignment of the sheet material in the conveyor direction (2) and perpendicular thereto takes placed by separate alignment elements (25) which can be triggered independently of one another during conveyance of the sheet material (1) with the process speed.

Abstract: The invention relates to a device for detecting the location of an edge (2) of a transparent, anisotropic material (3, 3′) comprising at least one sensor (1) with a light source (4), two polarization filters (6,7) with transmission axes (8,9) meeting at a 90° angle as well as a light detector (10), whereby the light source (4) and one polarization filter (6) are located on one side of the edge (2) to be detected and the second polarization filter (7) and the light detector are located on the other side.

Abstract: The invention relates to a method for the alignment of sheet-like material (1). Its alignment occurs via rotation elements (25), wherein the sheet-like material (1) is rotated around its central axis in order to print on the front and backsides. During the rotation of the sheet-like material (1) around its central axis, the material's leading edge (23) remains in its aligned position. Into the conveyor surface (9) is incorporated a sensor pair (30), preferably in the form of CCD line sensors, with which the sheet-like material (1) is aligned on the same lateral edge (24) following the rotation, as is the case during the alignment procedure of the sheet-like material (1) before it is rotated around its center axis.

Abstract: The invention relates to a process and a device for alignment of sheet material (1) which is conveyed in one conveyor plane (9). The sheet material is conveyed on bodies (35) of revolution and aligned by means of triggerable alignment elements (25) in the conveyor direction (22) and perpendicular to the conveyor direction (22). The alignment elements (25) are assigned to an alignment unit (8). The alignment motion necessary for alignment of the sheet material in the conveyor direction (2) and perpendicular thereto takes placed by separate alignment elements (25) which can be triggered independently of one another during conveyance of the sheet material (1) with the process speed.

Abstract: The invention relates to a process for compensation of dimension changes on sheet material (1) which is first provided with a printed image (36) on the front (35) and which is then provided with a printed image (40) on its back (39). The dimensions (41, 42) of the sheet material (1) are determined before an image is printed on the front (35) and before an image is printed on the back (39), and before an image is printed on the back (39) of the sheet material (1) the latter is centered to its position when the image was printed on the front (35).