JPH01247166A - Ink volume fixing device for ink arrangement - Google Patents

Abstract

PURPOSE:To achieve timesaving for adjustment of opening degree of ink fountains and to improve printing quality, by providing a conversion part with a system in which transfer functions are provided for each of divided bottom plates (blades) of divided ink fountains. CONSTITUTION:A transfer functions preparing arithmetic unit 18 in a conversion part 15 prepares new transfer functions with procedures of reading out some of optimum degree of blades opening records from the data stored in a printing data memory 17 and by method of least squres or by a method of obtaining mean values of blade opening degrees for each pattern area proportions. The new transfer functions are transferred to a transfer function memory 19 and replace corresponding old transfer functions. The new transfer functions thus stored are used in a transfer arithmetic unit 20 at the time of next printing. An output unit 21 always outputs the optimum degree of blades opening and the output data are transferred to an ink volume control unit 8. The ink volume control unit 8, based on the input data of the optimum degree of blades opening, gives commands to each of ink arrangement 1Y, 1M, 1C and 1B of each of printing units UY, UM, UC and UB for adjustment of the blade opening degrees. In accordance with these commands, each ink arrangement operates each blade B1-Bn independently to be opened at the optimum degree.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an ink amount setting device for a printing press, particularly a multicolor offset printing press.

[Conventional technology]

A multicolor offset printing machine prints in color.
For example, as shown in Figure 9, in the case of four-color printing, yellow (Y
), four printing units U each equipped with a printing plate responsible for each of the colors magenta (M), cyan (C), and black (B).

It is composed of U, U, and U8. Each printing shop C knit unit UY, UH, Uc, U8 has an inking device 1 that adjusts the amount of ink supplied. 1H, 1o, and 18 are provided, respectively.

Here, FIG. 10 shows the main parts of the inking device.

Each inking device1. ~IB have the same configuration, so 1° will be explained as an example. The inking device l includes an ink source roller 2,
The ink fountain 3 is provided with an ink fountain 3 disposed adjacent to the side of the outer peripheral surface of the ink source roller. The amount of ink is adjusted by the opening degree of the ink fountain formed by the relative gap between the tip of the bottom plate 4 of the ink fountain 3 and the outer peripheral surface of the ink source roller 2. The ink fountain bottom plate 4 is divided into a predetermined number of parts in the axial direction of the ink source roller 2, and each divided bottom plate (hereinafter referred to as a blade) 81 to B can independently adjust the opening degree tMy*. There is. The number of blades 81 to Bo (that is, the number of divisions of the bottom plate 4) corresponds to the number of divided areas Ar1 to Arn for measuring the plate area ratio of the printing plate 5, which are indicated by broken lines in FIG. This pattern area ratio is measured by a printing plate pattern area ratio meter of 0 or more ink device 1. is controlled by an ink amount setting device which receives the measurement data of the picture area ratio as input.

Next, a conventional ink amount setting device will be explained with reference to FIG. The conventional ink amount setting device is a pattern area ratio meter 6.
As input data, the measurement data is calculated as the pattern area ratio (%).
The corresponding pot opening (%) is determined by a preset conversion function.
), and an ink amount control section 8 that controls the adjusting device of each blade 81 to B of the ink fountain 3 based on the converted fountain opening degree data.

The pattern area ratio meter <DEMIA) 6 is a device that optically measures the amount of ink (i.e., pattern area ratio) necessary for color matching in the multicolor offset printing from the distribution of the pattern on the printing plate 5. The picture area ratio is measured for each printing plate (Y, C, M, B color), and the measured value is output on a medium such as a magnetic card or as a printout. The conversion unit 7 includes an input unit 9 for inputting measurement data of the pattern area ratio meter 6;
Conversion function data DY for each color (Y, C, M, B),
A conversion function memory 10 stores DC, DH, and DH (see Fig. 13) for each color, and a conversion calculation is performed by reading out the opening degree of the corresponding color from the conversion function memory 10 based on the input pattern area ratio measurement data. an output unit 12 that outputs conversion data; and an inverse conversion calculation unit 13 that converts the pot opening data from the ink amount control unit 8 to a pattern area ratio based on the conversion function memory 10; and an output section 9' that outputs the data inversely transformed by the inverse transformation calculation section 13.

As shown in FIG. 14, the conversion function data is expressed with the pattern area ratio (%) on the horizontal axis and the pot opening degree 100 (%) on the vertical axis.
, HC for each U8 (that is, for each color).

The ink amount control section 8 transmits the fountain opening degree data to each printing unit U based on the conversion data (fountain opening degree) from the output section 12.
It outputs to the inking devices IY to IB of ~U.

Next, the operation of setting the amount of ink when printing a certain pattern will be explained.

First, each printing plate 5 (Y) is determined by the pattern area ratio meter 6.

Measure the pattern area ratio of each of C, M, and B).

This picture area ratio measurement data is sent to the converting unit 7 via the input unit 9.
is input. In the case of a magnetic card, the input section 9 is used as a magnetic reader to automatically read the data, or in the case of printout data, the input section 9 is used as a keyboard for manual input. The input picture area ratio measurement data is input to the conversion calculation section 11.

The conversion calculation unit 11 reads conversion function data D, -D8 corresponding to each printing plate 5 from the conversion function memory 10 and outputs the pot opening degree corresponding to the input pattern area ratio to the output unit 12. The converted pot opening data is sent to the ink amount control section 8.
is input. The ink amount control unit 8 individually issues a fountain opening command to each printing unit Uv, UN corresponding to each printing plate 5.
, Uc, Us inking device 1. 1. 1. 1
(Illustration omitted) Give to HCB. Each inking device1. ．． IH, io, 18 adjusts the ink fountain 3 so that it conforms to the fountain opening command given to it.
However, if the pot opening degree obtained in the above manner is not fi, the operator manually opens the individual blades 81 to B using the keyboard of the correction input section 14. By this operation each printing unit U, performs an adjustment.

Inking device 1 of U, U, U, IH, l
The amount of ink ejected from IC9HCB Y 18 is the same as that of each corresponding printing plate 5 (
The amount is set to match the pattern of Y, M, C, B).

[Problem to be solved by the invention]

The problem with the above-mentioned conventional ink amount setting device is that each inking device 1. 1. 1. IHC in iB The ink fountain bottom plate 4 and the ink source roller 2 deteriorate over time due to wear, etc., and a deviation occurs between the initially set fountain opening and the actual fountain opening, which inevitably causes a decline in printing quality. The point is that it will be done.

Changes in the fountain opening degree over time can be dealt with by changing the conversion function and resetting the fountain opening degree. However, this resetting is for the opening degree of the entire ink fountain bottom plate 4, and the ink fountain opening degree cannot be changed over time. The wear of the ink fountain bottom plate 4 and the ink source roller 2, which is caused by individual blades B1 to Bn of the fountain bottom plate 4, does not necessarily occur uniformly over the entire width direction, but occurs locally. 0 If significant wear occurs locally, replace the corresponding blade (8
1 to B) will be replaced with a new one for maintenance purposes, but in this case readjustment is required to balance the pot opening with other blades that are still old. This readjustment is performed for each blade 81-Bn, but since there are subtle differences in characteristics between each blade 81-Bn, it is not possible to easily restore the optimum state. requires a lot of time and effort.

In this way, conventionally, the fountain opening degree is set uniformly for each printing unit, so that it is possible to cope with changes over time in the fountain opening degree that occur between the blades 81 to Bo of the ink fountain bottom plate 4. The problem was that it was not possible.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an ink amount setting device that can set the optimum fountain opening degree by applying a conversion function suitable for the picture area ratio of the printing plate to each blade of the ink fountain bottom plate. do.

[Means to solve the problem]

The present invention aims to solve the above-mentioned conventional problems, and in order to achieve the object of the present invention, as shown in FIG. The ink amount setting device of the inking device 1 to IB using the fountain 3 converts the image area ratio measurement data of the printing plate into the opening degree data of the ink fountain based on a preset conversion function. The ink amount setting device for setting the opening degree is characterized in that it has a conversion section 15 in which the conversion function is set for each of the divided bottom plates (blades) B1 to B0 of the divided ink fountain.

[Effect]

According to the configuration of the present invention, by inputting the measured pattern area ratio data, the divided bottom plate of each ink fountain bottom plate 4 is calculated based on the conversion function corresponding to each divided area for measuring the pattern area ratio of the printing plate. It is converted into a pot opening degree every 81 to B. Depending on the conversion data, each divided bottom plate B1-B! & You can set the appropriate pressure point opening.

As described above, according to the present invention, since the pot opening degree corresponding to the pattern area ratio can be directly and independently set for each divided bottom plate, it is possible to change the pot opening degree for each divided bottom plate over time. This makes it possible to improve printing quality and eliminate the trouble of adjusting the pot opening.

〔Example〕

Next, an embodiment of the ink amount setting device according to the present invention will be described based on the drawings.

FIG. 2 shows an embodiment of the present invention. In this FIG.
The same reference numerals are given to the same parts as those in FIG. 12 (conventional example) and the explanation will be given below.

The difference between the present embodiment shown in FIG. 1 and the conventional example shown in FIG. A print data memory 17 that stores the area ratio data and the optimum blade opening degree obtained by performing marking 7j for each divided area for measuring the image area ratio for each printing plate, and reads data from this print data memory 17. a conversion function creation calculation unit 18 that creates a conversion function for converting pattern area ratio data into blade opening data, and a conversion function memory 19 that stores the created conversion functions for each of the blades 81 to Bo. A conversion calculation section 20 reads a corresponding conversion function from the conversion function memory 19 based on the input pattern area ratio measurement data, calculates and outputs the optimum pot opening degree for each blade 81 to Bo, and calculates and outputs the optimum pot opening degree for each blade 81 to Bo. The output unit 21 outputs the output to the amount control unit 8.

Next, the operation will be explained according to the flowchart shown in FIG.

Healing! 100) Measurement data of the picture area ratio is input to the input section 16. This picture area ratio measurement data may be obtained from the magnetic card 2, for example, as shown in FIG.
2 and is input. Therefore, in this case, the input section 16 is composed of a card reader. The content of the measurement data of the pattern area ratio is as shown in Figure 4 for printing item (a).
Each divided area Ar1. of the printing plate 5. A, 2...Ar
n (see FIG. 11). The measurement data of the pattern area ratio thus provided is provided to the conversion calculation section 20 and print data memory 17, and is subjected to conversion calculation.

(Step 101 The conversion calculation is a step of calculating the blade opening degree of each blade 81 to Bo corresponding to the input pattern area ratio measurement data.

That is, as shown in FIG. 5, the print data memory 17 stores the image area ratio of each divided area of the printing plate 5 determined at the time of setting up the printing press, and the image area ratio of each blade corresponding to each divided area. Blade opening data is stored for each item a to n, printing units UY to UB, and blades 81 to B (hereinafter referred to as grisset data). This preset data is stored by the conversion function creation calculation unit 18. Read out sequentially. The conversion function creation calculation unit 18 converts each printing unit U to UB and each blade B to B based on the preset data read from the print data memory 7.
Create the conversion functions D81-Dan for each of the created conversion functions DB1-D. are stored in the conversion function memory 9 in association with each of the blades 81 to Bo for each printing unit UY to U8, as shown in FIG. When the image area ratio measurement data is input, the conversion calculation unit 20 calculates the corresponding conversion function D8 from the conversion function memory 9.
1 to D8n are read out, and a blade opening degree matching the input pattern area ratio measurement data is calculated. The calculated blade opening degree is outputted to the ink amount control section 8 by the output section 21.

The above is the operation when calculating the blade opening degree using the preset data at the time of printing press setting when there is no change over time in the blades 81 to B of the ink fountain 3. However, as mentioned earlier, the characteristics of the blades 81 to Bo change due to repeated printing, and the ink source roller 2 (Fig. 10) changes from its original state due to palm wear, etc. be.

Therefore, in the converting unit 15 in this embodiment, the blade opening degree (actual data) determined to be f&appropriate in past printing is fed back from the ink control unit 8 (step 102), and updated and stored in the print data memory 17. (See Figures 2 and 3).Whether or not the actual blade opening degree data is optimal is determined by inspecting the finished printed material. That is, in the process of printing several times, the performance data of the optimum blade opening degree is sequentially stored in the print data memory 17 as shown in the table shown in FIG. The data contents are updated sequentially.

The number of actual data to be stored is how many times in the past (for example, 1
0 times, etc.), and the data is used for calculation by the conversion function creation calculation section 18, which will be described later.

The conversion function creation calculation section 18 reads out some of the optimum blade opening performance data stored in the print data memory 17 and uses the least squares method as shown in FIG. 7 or the method as shown in FIG. A new conversion function is created using a method such as finding the average value of the blade opening for each pattern area ratio.

The created new conversion function is sent to the conversion function memory 19 and replaced with the corresponding old conversion function. Then, it is used in the conversion calculation section 20 during the next printing, and is used in the output section 2.
From 1 onwards, the optimum blade opening degree will always be output.

In this way, the initially set preset data is updated to new data each time the printing is repeated due to self-learning, and the blade opening degree is always calculated to suit changes in the blade over time. . Note that the update period of the conversion function does not necessarily have to be every printing, and may be set to a period that correlates with changes over time of the blades 81 to B, etc.

Zusuji 22ri Hadashaku” Me E Epidemic! - The optimum blade opening degree determined by the conversion section 15 is given to the ink amount control section 8. The ink amount control unit 8 controls each printing unit UY, UH based on the input optimum blade opening degree.
, Uc, and UB inking devices 1. 1. 1. 1
Give the HCB blade opening adjustment command to each of them. Each inking device 1. 1. 1.

In MC 1, each of the blades 81 to 81B is individually and independently operated to adjust the blade opening degree to an optimum degree.

Blade n agency positive (step 104) Perform trial printing with the adjusted blade opening.

If the inspection results show that the blade is defective, the operator uses the correction input unit 14 to correct and adjust the blade opening of the defective blade (any of 81 to B). As mentioned above, the obtained performance data is fed back to the print data memory 7.

Mark ψ (Step 105) Printing is performed with the blade opening set as described above. When the printing plate 5 is replaced in order to print a new item, the above-mentioned operation is repeated in the same way.During this repetition process, the blades 81 to Bo and the ink source roller 2 change over time due to self-learning action. Following the change, the conversion function of the conversion unit 7 is corrected and updated to a conversion function that provides the optimum blade opening. In this way, print quality can be improved. Moreover, the blade opening degree adjustment is not performed by converting the entire bottom plate 4 of the ink fountain 3 all at once using one conversion function, but is performed for each blade 81 to B individually based on the optimal conversion function. Therefore, each blade 81~
It is possible to correct the variation between B n colors and to make more fine-grained adjustments, thereby achieving an improvement in the printing quality of the layers, as well as saving the operator's manual adjustment effort and trial printing time.

〔Effect of the invention〕

As described above, in an ink fountain with a divided bottom plate, even if deterioration occurs over time between the divided plates and the opening degree varies, according to the present invention, each divided plate can be Since a conversion function suitable for the picture area ratio can be set, it is possible to finely and automatically set the opening degree of each dividing plate side. As a result, printing quality can be improved, and the amount of time required for workers to manually adjust the pot opening during test printing can be reduced. It is possible to save time and effort for maintenance such as opening adjustment.

[Brief explanation of the drawing]

Fig. 1 is a diagram corresponding to claims of the present invention, Fig. 2 is a block diagram showing an embodiment of the invention, Fig. 3 is a flowchart showing the operation of the invention, and Fig. 4 is data for measuring picture area ratio in a magnetic card. Figure 5 is an explanatory diagram showing an example of data stored in the print data memory, Figure 6 is an explanatory diagram showing an example of data stored in the conversion function memory, and Figure 7 is created using the least squares method. FIG. 8 is an explanatory diagram showing an example of a conversion function created by the average value method. FIG. 9 is an explanatory diagram showing an overview of a printing press with a general four-color unit configuration. 10 is a perspective view showing the ink fountain, FIG. 11 is an explanatory view showing the measurement area of the image area ratio of the printing plate, and FIG. 12 is a block diagram showing an example of a conventional ink amount setting device.
FIG. 3 is an explanatory diagram showing an example of the contents stored in the conversion function memory, and FIG. 14 is an explanatory diagram showing an example of the conversion function for converting the picture area ratio to the open opening degree. 1. 1c, 1. 1... Inking device, 2...
Ink source roller, 3... Ink fountain, 4... Ink bottom plate, 5... Printing plate, 6... Image area ratio meter, 8... Ink amount control unit, 15... Conversion Part, u, U, U
, U8...Print CH printing unit, B, B,..., B...blade. 12 n Applicant's agent Yasushi Ishikawa Figure 1 Figure 3 Figure 6 Figure 13 IF Peng Figure 14

Claims (1)

[Claims] For an ink amount setting device for an inking device using an ink fountain whose bottom plate is divided into a plurality of parts in the width direction of an ink source roller,
In an ink amount setting device that sets the opening degree of the ink fountain by converting pattern area ratio measurement data of a printing plate into ink fountain opening data based on a preset conversion function, the conversion function is divided into the ink fountain opening data. 1. An ink amount setting device for an inking device, comprising a conversion section set for each bottom plate of an ink fountain.