EP3042768B1 - Print control strips with split marks - Google Patents

Description

The invention relates to a device for regulating the position of a printing material in the circumferential direction in printing machines processing machines having the features of claim 1.

For quality control of print images, a print control strip is applied to the substrate laterally of the actual print image. This consists of several color zones, which in turn consist of a repetitive sequence of color fields. Regularly a color zone is 32.5mm wide and consists of ten equally sized color fields. If further production steps are connected to the printing process, further markings are sometimes needed on the substrate. For example, when punching printed products. In this case, the printed product must be introduced in the correct position in the punch, because the final product would otherwise be faulty and unusable. To ensure this, circumferential marks on the peripheral side and side marks on an adjacent side are regularly applied. A perimeter mark, of which at least two are required for the diagonal register, must be 18mm to 20mm wide due to the varying scale quality so that it can always be detected by a fixed camera. This means it can not be easily integrated into a color zone. One possible option for positioning these perimeter marks is next to the print control strip. As a result, however, more area is needed off the printed image. However, because the area occupied by print control bars and perimeter marks is removed in the printing process and ends up as a waste product, the placement of perimeter marks over the print control strip results in increased waste of substrates.

However, it is also possible to replace a color zone with a perimeter mark. Although this saves space and therefore material, the print quality of this color zone can no longer be measured directly. It can only be determined by means of a neighboring zone regulation - ie from the mean values of the two neighboring color zones become. Due to possible deviations from the mean value, quality losses that can not be detected directly can occur.

From the publication DE 43 35 350 A1 For example, a method and apparatus for detecting registration deviations in multicolor, printed-product-printed products which acquire a series of measurement areas printed on a substrate are disclosed. Such a measuring field is suitable for containing the usual printing inks black, cyan, magenta and yellow. Control fields, direction fields and solid fields are arranged in the measuring field. In each case, three control fields are provided for the lateral register and three control fields for the circumferential register. The control fields consist of equidistant lines of the printing ink black, whereby the gaps in between are filled with one of the remaining printing colors yellow, cyan or magenta. The width of the lines is on the order of 0.1 to 0.5 mm. With ten strokes, this results in a size of the control field of a maximum of about 5 mm ² , so that a measuring field results in small size, which can be easily accommodate in the pressure-free space.

The European patent application EP 2 008 818 A2 shows an improved print control strip for color measurement on substrates. The improved print control strip has in particular measuring fields, which are arranged in at least two rows parallel to each other. This two- or multi-row arrangement serves to be able to make cross-comparisons between measurement fields of the rows in order to be able to check the plausibility of measurements. The print control strip in each row contains a series of color measurement fields for each color zone. Such a color zone is repeated across the transport direction of the printing material across the entire width of the printing material. In the sheet format 102, usually 32 of the ink zones are lined up in a row. Between the individual ink zones, the print control strip may have gaps or additional measuring fields, for example for register control or register control.

From the patent US 4,546,700 For example, a method and apparatus for detecting and correcting color aberrations emerges. It's about To detect and minimize deviations in the register between the colors. For this purpose, predetermined register marks are applied in areas without a print image on the printing substrate. In four-color printing, the color black is typically selected as the reference color, so that the registers of the other three colors are regulated to the black image in the register. For this purpose, a register mark is printed in the same place for each of the three process colors as the corresponding black register mark. Furthermore, to control the color quality print control strips are applied, which are detected by a colorimeter, wherein the print control strips are arranged transversely to the printing direction over the entire width of the printing material. In particular, the colorimeter strips and the register marks may be arranged in a row.

Object of the present invention is to provide a device and brands for controlling the position of a substrate in the circumferential direction in substrates processing machines, which wastes a minimum of material and thereby achieves maximum print quality.

The present invention comprises a device and marks for regulating the position of a printing substrate in the circumferential direction in printing machines processing machines. At least three sensors are used, one of which detects the lateral position and two the circumferential register of a printing material.

The invention is characterized in that the two sensors which detect the circumferential register are arranged laterally offset by a multiple plus a fraction of a color measuring field and detect an edge of a colorimeter with Farbmessfeldern on the substrate. In this case, that sensor is evaluated after evaluation of the lateral sensor whose lateral evaluation range is within a color measurement field or a mark. For this, the color measurement fields themselves are used as circumference marks, or color measurement fields are replaced by marks. Since each color of a color measuring field has a different measuring characteristic, it must be determined on the basis of the positions of the color measuring fields on the substrate and the position of the substrate determined by the lateral sensor, which color measuring field is detected by a peripheral sensor. By using two at least one color zone plus a fraction of a color measuring field arranged circumferentially offset sensors can be assigned to avoid coordination problems in the boundary regions of two color fields, since one of the two circumference sensors is definitely within a clearly assignable color field. Thus, all color fields and all color zones can be measured without the use of the neighboring zone control as well as without the application of additional marks on the substrate.
However, all color fields must have a sufficient contrast to the background, which can not be guaranteed in all cases.

Therefore, an advantageous development of the invention provides that at least two color measuring fields of a color zone are replaced by a circumferential mark for detecting the position of the printing material. These are detected by the sensors of the circumferential register. Here, the contrast of these brands can be chosen so that an optimal detection is ensured by the sensors.

A preferred embodiment of the invention provides that the last or first three color measurement fields of a color zone consisting of ten color measurement fields are replaced by a perimeter mark. Due to the width of these circumferential marks and the staggered arrangement of the sensors of the circumferential register, the required control margin of 18mm to 20mm can be covered. Thus, an optimal layer measurement can be accompanied by an optimal color measurement of seven color fields. If the color of the circumference marks is chosen so that it corresponds to a color that already occurs in the printed image anyway, and provides sufficient contrast to the background, even a control of 8 colors is possible.

A further development of the invention provides that the circumferential mark can be lower than a color measuring field. This is useful if you do not need to control more than seven colors. This way, you can save color, which has to be spent extra for the perimeter markers.

A next advantageous embodiment of the invention provides that on a substrate, possibly the original sheet, the at least two circumferential marks are detected by the at least two sensors of the circumferential register. The substrate has a side mark, which is located on the side. This in turn is detected by the side sensor. Now, the areas of the perimeter marks are stored relative to the position of the page mark. So it is the side sensor later possible to determine the hand of the position of the detected page mark the sensor of the circumferential register, the evaluation area is within a color measurement field or within a perimeter mark. It is also possible to measure the colorimeter to detect and store any offsets between the colorimeters. Likewise, specific properties of the sensors can be measured depending on measured standardized Color measuring strips are recorded and stored. Thus, the influences of offsets and sensors can be eliminated by stored correction values. This process is also known as teaching.

In a further advantageous embodiment, the regions of the circumferential marks with respect to the position of the page mark are already detected and stored in a preliminary stage. These data are then transmitted from the precursor to the substrate processing machine so that they are available to the page sensor for evaluation of the relevant sensor of the circumferential register.

• Fig. 1 zeigt zwei benachbarte Farbzonen 8 mit jeweils 10 Farbmessfeldern 6, von denen jeweils die letzten drei eine Umfangsmarke 9 bilden. Weiterhin zu sehen sind die beiden Sensoren 3a und 3b, die um das 7,5-fache eines Farbmessfeldes versetzt angeordnet sind.
• Fig. 2 zeigt ebenfalls zwei benachbarte Farbzonen 8 mit jeweils 10 Farbmessfeldern 6, von denen jeweils die letzten drei eine Umfangsmarke 9 bilden sowie die beiden Sensoren 3a und 3b, die um das 7,5-fache eines Farbmessfeldes versetzt angeordnet sind. Hierbei sind die drei letzten Farbmessfelder 6, welche die Umfangsmarke 9 bilden in der Farbe schwarz ausgestaltet.
• Fig. 3 zeigt ebenfalls zwei benachbarte Farbzonen 8 mit jeweils 10 Farbmessfeldern 6, von denen jeweils die letzten drei eine Umfangsmarke 9 bilden sowie die beiden Sensoren 3a und 3b, die um das 7,5-fache eines Farbmessfeldes versetzt angeordnet sind. Hierbei sind die letzten drei Farbmessfelder 6 durch eine niedrige Umfangsmarke 9 ersetzt worden.
• Fig. 4 zeigt ebenfalls zwei benachbarte Farbzonen 8 mit jeweils 10 Farbmessfeldern 6. Hierbei sind die Sensoren 3a und 3b um das 9,5-fache eines Farbmessfeldes versetzt angeordnet und erfassen die Farbmessfelder 6 selbst.
• Fig. 5 zeigt einen Ausschnitt einer Bedruckstoffe verarbeitenden Maschine 2. Zu sehen ist ein Bogen 1, der in Schieflage innerhalb der Maschine 2 transportiert wird und ausgerichtet werden muss. Der Bogen 1 weist an der Umfangsseite einen Druckkontrollstreifen 7 auf. Weiterhin zu sehen sind zwei Farbzonen 8 des Druckkontrollstreifens 7, die wiederum aus jeweils 10 Farbmessfeldern 6 bestehen. Die letzten drei Farbmessfelder 6 einer Farbzone 8 bilden jeweils eine Umfangsmarke 9. Außerdem weist der Bogen 1 eine Seitenmarke 10 auf. Die Maschine 2 weist die Sensoren 3a und 3b auf, die um ein nicht ganzzahliges Vielfaches eines Farbmessfeldes versetzt innerhalb der Maschine 2 angeordnet sind, um die Umfangsmarken 9 zu erfassen. Daneben weist die Maschine einen Seitensensor 4 auf, der dazu dient die Seitenmarke 10 zu erfassen.

The inventive method and further advantageous embodiments are shown in the following embodiment and the drawings.

• Fig. 1 shows two adjacent ink zones 8 , each with 10 color fields 6, of which in each case the last three form a perimeter mark 9 . Also visible are the two sensors 3a and 3b, which are arranged offset by 7.5 times a color measuring field.
• Fig. 2 also shows two adjacent color zones 8 , each with 10 color fields 6, of which in each case the last three form a circumferential mark 9 and the two sensors 3a and 3b, which are arranged offset by 7.5 times a color measuring field. Here, the last three color fields 6, which form the circumferential mark 9 configured in the color black.
• Fig. 3 also shows two adjacent color zones 8 , each with 10 color fields 6, of which in each case the last three form a circumferential mark 9 and the two sensors 3a and 3b, which are arranged offset by 7.5 times a color measuring field. Here, the last three color fields 6 have been replaced by a low circumferential mark 9 .
• Fig. 4 also shows two adjacent color zones 8 , each with 10 color fields 6. Here, the sensors 3a and 3b are arranged offset by 9.5 times a color measurement field and detect the color measurement fields 6 itself.
• Fig. 5 shows a section of a substrate processing machine 2. To see is a sheet 1, which is transported in a tilted position within the machine 2 and must be aligned. The sheet 1 has on the peripheral side on a print control strip 7 . Also visible are two color zones 8 of the print control strip 7, which in turn consist of 10 color fields 6 . The last three color fields 6 of a color zone 8 each form a circumferential mark 9. In addition, the sheet 1 has a page mark 10 on. The machine 2 has the sensors 3a and 3b , which are arranged offset by a non-integer multiple of a color measuring field within the machine 2 to detect the circumferential marks 9 . In addition, the machine has a side sensor 4 , which serves to detect the side mark 10 .

An exemplary embodiment provides that a printed sheet 1 in a preliminary stage 11 of the printing material processing machine 2 is measured such that the regions of the circumferential marks 9 are detected with respect to the position of the side mark 10 . The data thus determined are then transmitted from the precursor 11 to the printing material processing machine 2 . The sheet is picked up by the printing material processing machine 2 and transported to the actual processing unit (such as a punch). Before this processing unit is reached, the print control strip 7 is detected by the two sensors 3a and 3b . A side sensor 4 detects the side mark 10. With the aid of the acquired data, the side sensor 4 determines the sensor 3a or 3b whose evaluation range lies within a circumference mark. From the data thus determined, the exact position of the sheet 1 in the machine 2 can be determined. So it is possible for a downstream unit to position the sheet 1 correctly.

LIST OF REFERENCE NUMBERS

1

substrate

2

Substrate processing machine

3a, 3b

Sensors of the circumferential register

4

side sensor

5

circumferential register

6

Color measurement field

7

Color bar

8th

color zone

9

extensive brand

10

page brand

11

preliminary stage

Claims (7)

1. Device for controlling the position of a printing material (1) in a circumferential direction in a machine (2) for processing printing material using at least 3 sensors (3a, 3b, 4), one (4) of which detects the lateral position and two (3a, 3b) of which detect the circumferential register (5),
   characterized in
   that the two circumferential register sensors (3a, 3b) are disposed to be laterally offset by a multiple plus a fraction of a colour measurement field (6) and detect an edge of a colour measurement strip (7) having colour measurement fields (6) or of a colour measurement strip (7) having colour measurement fields (6) and marks (9) on a printing material (1), and in that by analysing the lateral sensor that sensor (3a, 3b) is analysed whose analysation range is located within a colour measurement field (6) or a mark (9).
2. Device according to claim 1, wherein the colour measurement strip (7) consists of at least 2 ink zones (8) and wherein a respective ink zone consists of multiple colour measurement fields (6),
   characterized in
   that the two sensors (3a, 3b) of the circumferential register are disposed to be laterally offset by a multiple plus one half of a colour measurement field (6).
3. Device according to claim 1 or 2, wherein the colour measurement strip (7) consists of at least 2 ink zones (8) and wherein each ink zone consists of multiple colour measurement fields,
   characterized in
   that at least two of the colour measurement fields (6) in every ink zone (8) are replaced by a circumferential mark (9) for detecting the position of the printing material (1) by means of the at least two circumferential register sensors (3a, 3b).
4. Device according to the preceding claims,
   characterized in
   that a ink zone (8) consists of ten colour measurement fields (6), wherein the last or first three colour measurement fields (6) of every ink zone (8) are replaced by a circumferential mark (9) for detecting the position of the printing material (1) by means of the two circumferential register sensors (3a, 3b).
5. Device according to the preceding claims,
   characterized in
   that the circumferential mark (9) is lower than a colour measurement field (6).
6. Device according to the preceding claims,
   characterized in
   that the at least two circumferential marks (9) are detected on a printing material (1) by the at least two circumferential register sensors (3a, 3b), wherein a side mark (10) located on the printing material (1) is detected by the lateral sensor (4) and the regions of the circumferential marks (3a, 3b) relative to the position of the side mark (10) are saved.
7. Device according to claims 1 to 5,
   characterized in
   that the regions of the circumferential marks (3a, 3b) are established and saved in a prepress stage with reference to the position of a side mark (10) located laterally on the printing material (1) and that the prepress stage (11) transmits the saved data to the machine (2) for processing printing material.

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