JPH1034893A - Method for deciding regulating amount for register regulator of sheet-feed printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To release an operator from an intelligent job by automatically deciding a position of a measuring place to measure respective registers, and utilizing it in case of normalizing a regulating amount to be input by the operator to a physical amount. SOLUTION: A sheet 3 is printed by two colors with inks of black B and cyan C. A coordinate axis (y) is placed in parallel with a printing direction 8. An operator decides measured values y1, y2 of a circumferential direction at measuring places P1, P2, and then obtains positions x1, x2 of a magnifying lens in a sidewise direction (x) without illuminating photoreceivers in the case of placing the lens at the places P1, P2. Thus, a diagonal register deviation based on (x2-x1) is calculated by a simple mathematical relation. Since an operating place for a regulating means is separated from x coordinates x1, x2 of the places P1, P2 in the sidewise direction (x), a regulating amount to be input by an input member is obtained from a product of the deviation and a correction coefficient. Thus, normalization of the regulating amount at a regulating place xV of a value of a diagonal register is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for determining an adjustment amount for a register adjusting device of a sheet-fed printing press. The invention can be used in sheet-fed printing machines in which compensation for diagonal or diagonal registration is taken into account.

[0002]

2. Description of the Prior Art It is known to measure misregistration with a hand-held measuring instrument and to determine the amount of adjustment for a register adjustment device from the measured values obtained. It is, in fact,
This is performed by the driver placing a sheet on the inspection table and determining the misregistration on two different measurement locations. For the measurement of misregistration oblique to the printing direction, i.e., diagonally, in principle, the driver should be as close as possible to each edge of the sheet in a direction perpendicular to the printing direction. Select two measurement locations, and on these two measurement locations, in addition to misregistration in the direction perpendicular to the printing direction, that is, so-called lateral misregistration, misregistration in the printing direction, that is, circumferential misregistration. Also measure. From the difference between the two circumferential misregistrations, the oblique misregistration, that is, the diagonal misregistration, is determined. Therefore, the concept of the diagonal misregistration will be used in the following description.

A register adjusting device for compensating for diagonal misregistration includes adjusting elements which, when actuated, enable the relative rotation of the color picture to be overprinted on the sheet. . In one known example of a register adjusting device on a sheet-fed printing press, a plurality of plate cylinders are respectively supported so as to be pivotable, and the rotation is such that one bearing is moved while the other is moved. Is achieved by having a center of rotation. The amount of adjustment to be entered by the driver to compensate for diagonal misregistration is proportional to the bearing travel described above. Due to the unilateral movement of the plate cylinder, the axis of rotation of the plate cylinder is not parallel to the axis of rotation of the associated blanket cylinder. In this case, the adjustment amount to be input by the driver does not correspond to the magnitude of the diagonal misregistration. This is because the measurement place and the operation place for movement are far from each other. The driver must start from the magnitude of the diagonal misregistration if two measurement locations are selected at some distance from the center of rotation of the plate cylinder and the operating location of the adjustment element that realizes the movement. An estimate must be made of how much the adjustment to be entered for the move must be scaled up. If the driver selects a different measuring location for the next printed sheet than for the already printed and measured sheet, the driver must make a new estimate. The determination of the amount of adjustment for diagonal register adjustment therefore depends on the driver's attention and experience. The time required for compensating for diagonal misregistration is inevitably long. This is because the estimate made by the driver is only approximately accurate and requires further correction of the diagonal misregistration thereafter.

In order to avoid such disadvantages, in the device according to DE 39 24 989 A1, the driver is instructed (for example) by coordinates for the measuring location of the register measurement, Will monitor whether it is actually measuring at the indicated measurement location.
If the driver applies the hand-held measuring device to a place on the sheet that is not as indicated, then such a place does not emit a measuring signal, or
An error signal is signaled. By always taking measurements at the same measurement location, the driver is relieved of the burden of the aforementioned estimation. This is because the driver can determine the amount of adjustment starting from constant geometric measurement and adjustment figures.

[0005]

In this case, it is disadvantageous that the driver no longer has a choice of where to determine the misregistration because the coordinates for the measurement location are specified. . During the printing process, it may be useful to change the measurement location. According to the solution according to German Patent Application 39 24 989 A1, this also requires several steps for the device to remember, ie to enter, the measuring location to be newly aimed. In addition, since the driver has to aim at the designated measurement location mentioned above,
Again, it is disadvantageous that the driver loses time to finish placing the hand-held meter at the target location on the paper sheet. During that time, the sheet-fed printing press prints the misregistered sheet.

It is an object of the present invention to provide a method for determining the amount of adjustment for a register adjustment device in which the driver is largely free from intellectual duties and the driver is free to choose the measuring location. It is in.

[0007]

SUMMARY OF THE INVENTION For this purpose, the position of the measurement location is automatically determined for each registration measurement, and the position information is used to physically adjust the amount of adjustment to be entered by the driver. It is achieved by a method characterized in that it is used during normalization to quantity.

The coordinates of the measurement location are automatically determined together with each measurement of the misregistration, and are used for normalizing the adjustment amount to be input by the driver to the physical adjustment amount.
Regardless of the location of the measurement, it is always possible to determine a physical adjustment that will result in a rapid compensation of the misregistration.

One advantageous device for the automatic determination of the position of the measuring site is to receive a plurality of equally spaced individual light beams in discrete directions in the printing direction of the sheet to be measured. It consists of a light transmitting device for transmitting the light to the vessel. When the hand-held measuring device is placed on a sheet, at least one of the parallel rays is interrupted. The corresponding light receiver is not illuminated, from which a signal can be emitted as to the position of the hand-held measuring device on the sheet.

[0010]

Next, embodiments of the present invention will be described with reference to the drawings.

In FIG. 1, an inspection table 1 is shown,
A paper sheet 3 is placed on the mounting surface 2 for register measurement. The examination table 1 is provided with input members 4, 5 for inking and a register adjusting device, and for the position of each adjusting member for inking which works for each zone, and in the printing direction 8 and at right angles thereto. It includes display members 6, 7 for the absolute value of the position of the register adjustment device. In a direction perpendicular to the printing direction 8, there are strips 9 and 10 on the inspection table 1, each of which has a light emitter 11 and a light receiver 12. The strips 9 and 10 are placed parallel to the edge of the mounting surface 2. A plurality of light emitters 11 emit light beams 13 which are parallel to one another and are equally spaced. In this embodiment, the spacing of the rays 13 corresponds to the spacing between the zones where the inking can be adjusted. A light receiver 12 accurately corresponds to each light emitter 11. A loupe 14 is provided for measuring misregistration in the printing direction 8 and in a direction perpendicular thereto. Loupe 14 is paper leaf 3
Above, it is placed on a measuring station freely selected by the printing press driver. By placing the loupe 14, the light beam 15 is interrupted, so that the corresponding light receiver 16 does not receive light.

FIG. 2 shows in detail how to obtain measured values. The lateral direction and the circumferential direction are indicated by the coordinate axes x and y, and the coordinate axis y is placed parallel to the printing direction 8. Two-color printing is performed on the paper sheet 3 with black B and cyan C inks. To determine the diagonal misregistration, the driver has already determined the measured values y1 and y2 at the measurement locations P1 and P2. When the loupe 14 is placed on the measuring points P1 and P2, the respective light receiver 12 or 16 is not illuminated, so that the positions x1 and x2 of the loupe 14 in the lateral direction x are obtained therefrom. According to a simple mathematical relationship, a diagonal misregistration based on (x2-x1) is calculated as Δ = y2-y1. Here, y1 =
y1B-y1C, and y2 = y2B-y2C.
The values y1B, y1C, y2B and y2C are absolute values for the colors on the measurement locations P1 and P2, ie the positions of black B and cyan C.

In FIG. 2, the color value on the paper sheet 3 to be printed next, that is, the coordinate value in the lateral direction where the adjusting means for register adjustment of black B and cyan C acts is xV.
Indicated by Since the operation place for the adjusting means is apart from the x-coordinates x1 and x2 of the measurement places P1 and P2 in the lateral direction x, the value to be input by the input member 5 is
It must be determined using a correction factor that takes into account the deviation. The adjustment amount to be input is the diagonal misregistration Δ
And the correction coefficient K. Here, K is obtained from the following equation.

K = (xV-x1) / (x2-x1) The calculation of the adjustment amount to be input can be performed by using a computer, and the signal of the light receiver 12 is represented by a coordinate value x.
1, x2, which is used in calculating the correction coefficient K or the product K · Δ.

[0015] Thereby, the normalization of the diagonal register value to the adjustment amount at the adjustment location xV is achieved. Entering an adjustment amount for one of the colors B, C is sufficient when the other color B, C at that time is defined as a so-called reference color.

In FIG. 3, the relative rotation of the color separation pattern is determined by the rotation axis 17 of the plate cylinder of one of the colors B or C.
It shows in detail how register corrections can be made when they can be reached by skewing. In the usual case, the plate cylinder is supported on both sides, one bearing allows a pivoting movement 18 of the axis of rotation 17 about a pivot 19 and the second bearing is moved from the starting position 20. It can move up to the maximum adjustment value 21,22. Departure position 2
At 0, the plate cylinder is located parallel to the transfer cylinder if the printing press is an offset printing press. During the movement of the second bearing described above, it carries out a circular movement on the path 23.

In FIG. 3, furthermore, the registration can be corrected by adjusting the circumferential register and the lateral register in the first stage and adjusting the diagonal register in the second stage. It is shown that. According to FIG. 3, we start from a misregistration of color C with respect to field color B. Line 24 shows the starting position for color C.
In the first stage, the misregistration in the circumferential direction y is corrected, which is indicated by the line 25. Line 25 emerges from line 24 by translation. This corresponds to adjustment of the circumferential registration of the printing plate. In the second stage,
The second bearing is moved towards the maximum adjustment value 22. Oscillation of the plate cylinder about the pivot center 19 produces a line 26 where the colors B and C exactly overlap each other.
The slight lateral misregistration caused by moving on the path 23 is negligibly small, especially at measurement locations that are far away from the pivot point 19.

The method of the present invention is not limited to two-color technology. This method can in principle also be used for the overprinting of any number of colors. In each case, for the determination of the amount of adjustment for compensating for the diagonal misregistration of the color to be adjusted with respect to the color of the field, two different measurement positions are determined for each pair of colors. Measurement is required. The use of the coordinate values of those measurement locations in the lateral direction is still similar to the method described above.

[Brief description of the drawings]

FIG. 1 is a plan view of an inspection table with a device for determining a measurement place.

FIG. 2 is an explanatory diagram of measurement locations to be considered when correcting diagonal register.

FIG. 3 is a schematic diagram with an adjustment movement possible for register adjustment.

[Explanation of symbols]

 Reference Signs List 1 inspection table 2 mounting surface 3 paper sheet 4 input member (for ink) 5 input member (for register) 6 display member (for ink) 7 display member (for register) 8 printing direction 9 band 10 band 11 light emitting device 12 Light receiving device 13 Light beam 14 Loupe 15 Light beam 16 Light receiving device 17 Rotation axis (plate cylinder) 18 Swinging motion 19 Swing center 20 Starting position 21, 22 Maximum adjustment value 23 Path 24 Line (original position) 25 Line (After translation) Line 26 (after turning)

 ────────────────────────────────────────────────── ─── Continuation of the front page (71) Applicant 390009232 Kurfuersten-Anlage 52-60, Heidelberg, Federal Republic of Germany (72) Inventor Holger Leonhard, Germany 69245 Barmenter Le Johann-Sebastian-Sachstahl-Schacher-Sbacher 51 (72) Inventor Gerhard Panners Germany 74889 Zinsheim Doctor-Eschl-Strase 27

Claims (1)

[Claims] 1. An adjustment quantity is derived from register measurements with a hand-held measuring instrument at at least two different measuring points, the adjustment quantity being to be performed for compensating misregistration. A method for determining the amount of adjustment in a register adjustment device of a sheet-fed printing press, which contains one value for the relative rotation of the color separation pattern to be printed, comprising: The position of P1, P2) is automatically determined, and the position information is used when normalizing the adjustment amount to be input by the driver into the physical adjustment amount, A method for determining an adjustment amount for a register adjusting device of a leaf printing press.