JP6183882B2 - Printer - Google Patents

Description

  The present invention relates to a printing press provided with a color tone measuring device. In the present invention, the color tone indicates a color difference or density, and serves as an index for evaluating the quality of a printed matter printed by a printing press.

  A printing press provided with a color tone measuring device is known, and quality evaluation of printed matter printed by the printing press is possible. The printed material is placed on the table of the measuring device, and the color tone of the printed material is measured by the measuring unit of the measuring device scanning the color bar printed over the paper width of the printed material. Based on the measurement result, the control unit can control the ink amount adjusting device of the printing press to keep the quality of the printed matter constant.

  The color bar is composed of a plurality of color patches (K, C, M, Y, gray, etc.). As for the measuring device, for example, in the case of a measuring device that measures density, a C filter, an M filter, and a Y filter corresponding to the three primary colors C, M, and Y are provided. Measure the concentration. In the case of a measuring device that measures color difference, for example, the Lab value of each color is measured. Japanese Patent Application Laid-Open No. 2004-133620 discloses a printing press provided with such a color tone measuring device.

JP 2001-293847 A

  In a conventional color tone measuring apparatus such as Patent Document 1, even when printing the same image (JOB), the control unit that controls the measuring apparatus controls the right and left ends of the color bar each time the paper width of the printed material to be printed is different. It is necessary to input the colors (K, C, M, Y, etc.) of the color patches. This is because even in the same image, the number of color patches is different if the paper width is different.

  Based on the input color patch color and paper size information, the control unit refers to a file (hereinafter referred to as “reference file”) that describes the arrangement of color patches, and the color of each color patch. The measurement result of the measuring device corresponding to is extracted. As described above, the feedback is made to the ink amount adjusting device. Therefore, for the operator, every time the paper size is changed, it is complicated to input the colors of the left and right color patches, and there is room for improvement.

  The present invention has been made to solve such problems, and an object of the present invention is to provide a printing machine capable of performing color tone measurement work reliably, quickly and easily.

In order to achieve the above object, the present invention achieves the color tone of a color bar comprising a printing unit capable of printing a fed sheet and a plurality of color patches arranged on a printed matter printed by the printing unit. A color tone measuring device capable of measuring the color tone, and a control unit capable of controlling the printing unit and the color tone measuring device, wherein the control unit refers to a color bar reference file in which a sequence of color patches is described. In the printing press for extracting the measurement result of the color tone measuring device, the control unit calculates the total number of patches of the color patch of the printed matter measured by the color tone measuring device , and obtains the center of the color bar by the following equation (1). , in correspondence of the center patch further determined color bar center and the reference file, the right and left ends of the color patches were measured with reference to the reference file and set its color, the reference following Wherein the arrangement of the color patches printed material corresponding to the sequence of color patches described in the Airu be automatically recognized.

Total number of patches / 2 + α (1)

(However, the calibration patch provided in a specific position of the color bar is paper white concentration from neighboring tentatively the obtained color bar centers by the total measurement patch number / 2 in the formula of said predetermined number are the colored patch, the concentration measurement of the predetermined number of patches, if the density value corresponding to the color that is not set in the printing unit does not meet the three conditions of low, from -4 to +4 Change α by 1 unit within the range )

  According to the printing press according to the present invention, it is possible to realize a printing press capable of performing color tone measurement work reliably, quickly and easily.

It is a figure which shows schematic structure of one Embodiment of the printing machine which concerns on this invention. It is a schematic perspective view of a color tone measuring apparatus. It is a principal part schematic plan view of a color tone measuring apparatus. It is a schematic block diagram which shows a control part. It is a figure which expands and shows the color bar in printed matter. It is a table | surface which shows the measurement result by the reference | standard file of a color bar, and a color tone measuring apparatus.

  Embodiments according to the present invention will be described below with reference to the drawings. In FIG. 1, parts having substantially the same configuration and action are denoted by the same reference numerals.

  The printing press shown in FIG. 1 includes a paper feeding unit 20, a printing unit 30, and a paper discharge unit 40. The paper feeding unit 20 can supply the sheet P to the printing unit 30 via the feeder board 5. The printing unit 30 can print the sheet P supplied from the paper feeding unit 20, and includes a plurality of printing units (here, four printing units 30a to 30d). Further, the paper discharge unit 40 can discharge the printed matter Q printed by the printing unit 30. In this printing machine, the sheet P is supplied from the paper supply unit 20 to the printing unit 30, and the supplied sheet P is printed by the printing units 30 a to 30 d in the printing unit 30, and then the printing is performed. The printed matter Q is discharged by the paper discharge unit 40.

  The paper feeding unit 20 can accommodate a plurality of sheets P, and pulls out the sheets P one by one from the uppermost sheet P and directs the sheets P toward the printing unit 30 through the feeder board 5. It can be conveyed in the direction of arrow Z. Thereby, the sheet P can be supplied to the printing unit 30.

  Each of the printing units 30a to 30d of the printing unit 30 includes the plate cylinder 1, the rubber cylinder 2, and the impression cylinder 3 as a set of main components. 4a in the printing unit 30a is a paper feed cylinder, and 4 in the printing units 30b to 30d is a transfer cylinder.

  In each of the printing units 30a to 30d, a printing plate (not shown) is disposed on the plate cylinder 1. In this plate, ink and water are supplied from an ink roller group which is an ink supply unit and a water supply device (not shown), and the ink is transferred to the rubber cylinder 2 according to the plate. The ink transferred to the rubber cylinder 2 is further transferred to the sheet P conveyed between the rubber cylinder 2 and the impression cylinder 3 while being sandwiched between grippers (not shown). As a result, printing can be performed corresponding to the plates provided on the sheet P supplied from the paper supply unit 20.

  The paper discharge unit 40 includes a transport unit 41 and a storage unit 42. In the paper discharge unit 40, the printed product Q conveyed by the impression cylinder 3 of the printing unit 30d is held at the leading end portion by a holding unit (not shown) of the conveyance unit 41, and on the substantially lower side surface of the conveyance unit 41 in the drawing. Then, it is conveyed to the accommodating portion 42. The storage unit 42 can store the printed material Q that has been transported by the transport unit 41.

  FIG. 2 shows a schematic perspective view of the color tone measuring device 50, and FIG. 3 shows a schematic plan view of the main part of the color tone measuring device 50. As shown in FIG. The color tone measuring apparatus 50 is a density measuring apparatus that measures color print density here, and includes a measuring unit 52 including a table 51 and a scanner 52f as shown in FIG. The color tone measuring device 50 scans the color bar 100 of the printed matter Q placed on the table 51 with the printing surface facing upward by the scanner 52f of the measuring unit 52, and print quality (here, density) of the color bar 100 is measured. Thus, the print quality of the color print image printed on the printed material Q is evaluated. A touch monitor T that can input an instruction to a control unit 80 of a printing press, which will be described later, is also provided on the side of the table 51.

  As shown in FIG. 3, the table 51 has a flat surface, and the printed material Q can be arranged at a predetermined position on the flat surface. The measurement unit 52 includes an X-axis guide 52a disposed along the arrow X direction in FIG. 3 and a pair of Y disposed along the arrow Y direction in FIG. 3 that is orthogonal to or substantially orthogonal to the arrow X direction. Axis guides 52b, 52b, movable along the arrow Y direction, and the above-described scanner 52f that moves in the arrow X direction on the pair of brackets 52c, 52c to which the X axis guide 52a is fixed and the X axis guide 52a. It has. Therefore, the scanner 52f can reciprocate in the directions of the arrows X and Y in FIG.

  FIG. 4 is a schematic block diagram showing the configuration of the control unit 80 according to the present invention. The control unit 80 includes a microprocessor 81 (may be a sequencer) that performs arithmetic processing, a ROM 82 that stores data and a predetermined program (such as an arithmetic expression or a table), a RAM 83 that can store a variety of information related to the machine speed, a micro It is configured using an interface 84 or the like that mediates exchange of various signals between the processor 81 and a device provided outside the control unit 80. The control unit 80 is connected to the printing units 30a to 30d, the color tone measuring device 50, and the touch monitor T described above.

  An automatic recognition operation of the color patch arrangement according to the present invention will be described with reference to FIGS. FIG. 5 is an enlarged view of the color bar 100 in the printed material Q, and FIG. 6 is a table showing the reference file of the color bar 100 describing the arrangement of the color patches and the measurement result of the color bar 100 by the color tone measuring device 50. It is. Note that “ink key No.” in FIG. 6 is the number of a plurality of ink keys provided in the width direction of the sheet P for supplying ink to the above-described ink roller group.

  When the measurement result of the color bar 100 measured by the color tone measuring device 50 shown in FIGS. 2 and 3 is sent to the control unit 80, the control unit 80 calculates the number of color patches constituting the measured color bar 100. Specifically, the color density is recognized by being recognized as different color patches based on the measured density value change. Then, the center of the color bar (center in the arrangement direction of the color patches) is obtained by the following formula 1.

Total number of measured patches / 2 + α ... Formula 1
In the present embodiment, α changes the range from −4 to +4 by one unit, but satisfies the following three conditions. The first condition is that the Cal patch (calibration patch) in the reference file has a paper white density (maximum density ≦ 0.1). In FIG. 102 (the 102nd color patch from the left end) corresponds to this, and ink is not applied here but is white. Note that patch No. 102 is a reference patch that is always printed on all paper sizes.

  The second condition is that a predetermined number of patches (color patches 115 to 119 in FIG. 5 in this embodiment) are colored from the side of the center patch provisionally obtained from the counted number of patches. (Maximum value of measured density ≧ 0.3), that is, the color patch is present properly.

  The third condition is that the density measurement values of the predetermined number of patches (color patches 115 to 119) have low density values corresponding to colors not set in the printing units 30a to 30d (maximum value ≦ 0). .1).

  Based on α thus obtained, a patch corresponding to the center patch (patch No. 120) of the reference file is set as the center of the color bar. The left and right ends of the measured patches are referred to the standard file, the corresponding colors are set as the left and right ends, the density corresponding to the color of each color patch is extracted, and the ink amount adjusting device of the printing unit 30 is controlled. To do. When the center patch cannot be obtained, the control unit 80 displays “The center cannot be found” on the touch monitor T. The reference file may be stored in the ROM 82 of the control unit 80, or an external storage medium storing the reference file may be connected to the control unit 80.

  As described above, since the control unit 80 automatically recognizes the arrangement of the color patches from the measurement result of the color tone measuring device 50, the operator does not need to input the left and right color patch colors every time the paper size is different, and can be quickly and easily performed. In addition, a reliable color tone measurement operation can be realized, and the printing operation time can be shortened.

  In addition, this invention is not limited to the above-mentioned embodiment, A various change is possible in the range which does not deviate from the summary of this invention. The scanning of the measurement unit 52 of the color tone measuring device 50 is automatic scanning, but may be manual scanning.

  In the above-described embodiment, the sheet-fed offset printing machine is used. However, the present invention is not limited to this, and a liquid toner printer, an ink jet printer, a gravure printer, It may be like a flexographic printing machine.

  The printer according to the present invention is extremely useful in a printer having a color tone measuring device.

  DESCRIPTION OF SYMBOLS 30 ... Printing part, 50 ... Color tone measuring device, 51 ... Table, 52 ... Measuring part, 52f ... Scanner, 80 ... Control part, 100 ... Color bar, 101-122 ... Color patch, Q ... Printed matter, T ... Touch monitor

Claims (1)

A color tone measuring device capable of measuring a color tone of a color bar composed of a printing unit capable of printing a fed sheet, and a plurality of color patches arranged on a printed matter printed by the printing unit; A print unit and a control unit capable of controlling the color tone measuring device, and the control unit extracts a measurement result of the color tone measuring device with reference to a color bar reference file in which a color patch arrangement is described In the machine
The control unit calculates the total number of patches of the color patch of the printed matter measured by the color tone measuring device, obtains the center of the color bar by the following equation (1), and further calculates the center of the obtained color bar and the reference file. Match the center patch and set the color of the measured color patch with respect to the left and right edges with reference to the standard file. the printer, which is a possible automatic recognition.

Total number of patches / 2 + α (1)

(However, the calibration patch provided in a specific position of the color bar is paper white concentration from neighboring tentatively the obtained color bar centers by the total measurement patch number / 2 in the formula of said predetermined number are the colored patch, the concentration measurement of the predetermined number of patches, if the density value corresponding to the color that is not set in the printing unit does not meet the three conditions of low, from -4 to +4 Change α by 1 unit within the range )

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