JP2010194961A - Ink supplying device, printing machine, and ink supplying method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress variance on ink film thickness in a width direction of printed matter in an ink supplying path when an ink film is formed on an ink supplying path at a printing preparation stage. <P>SOLUTION: An ink origin roller 104 draws ink from an ink bottle 101 included in a printing machine to supply it to an ink supplying path. A plurality of ink keys 109 are arrayed in a direction of a rotary axis Zi of the ink origin roller 104 to adjust an amount of ink drawn from the ink bottle 101 by the ink origin roller 104. At a preparation stage before the printing machine starts real printing, an opening degree of the ink key 109 is changed according to characteristics of the printing machine, which are grasped beforehand. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a technique for supplying ink to a printing plate attached to a plate cylinder of a printing press.

  In a printing machine, ink supplied from an ink supply source passes through an ink supply path constituted by a plurality of rollers until an image line is printed on a recording medium (paper). When supplying ink, an ink fountain roller that draws ink from an ink reservoir called an ink fountain and forms an ink film on the surface, and an ink delivery roller that delivers ink from the ink fountain roller to a roller connected to the plate cylinder There is a technology that uses. In Patent Document 1, for the purpose of forming an ink film corresponding to a change in printing conditions such as ink characteristics, the ink density value of a print sample after the start of printing is input, and the input ink density value is Based on this, an ink supply device for a printing press that controls the number of calls of the ink transfer roller when an ink film is formed on the ink roller before the start of printing is disclosed.

JP 2003-1799 A (0011-0013)

  When printing is started, if there is no ink on the ink supply path, it is necessary to form an ink film on the ink supply path. For this reason, as preparation before the main printing, ink is supplied from the ink reservoir to the ink base roller in a state where the roller group of the printing press is idle, and an ink film is formed in the ink supply path. In this case, as a first step, an ink film having a constant thickness is formed in the ink supply path in the width direction of the printed material (the rotation axis direction of the roller).

  However, the ink film thickness was controlled to be constant in the width direction of the printed matter due to the characteristics of the printing press itself due to the distribution of the nip pressure of the rollers existing in the ink supply path and the variation in the physical property values of the blanket. Even in this case, the ink film thickness may vary in the width direction of the printed matter. Since the technique disclosed in Patent Document 1 only changes the number of calls of the ink transfer roller, it is difficult to suppress variations in the ink film thickness in the width direction of the printed matter.

  The present invention has been made in view of the above, and in forming an ink film in an ink supply path in a printing preparation stage, suppresses variations in the ink film thickness in the width direction of the printed matter in the ink supply path. With the goal.

  In order to solve the above-described problems and achieve the object, an ink supply device according to the present invention includes a plurality of ink reservoirs arranged in the direction of the rotation axis of an ink source roller that draws ink from an ink reservoir provided in a printing press. Ink key for adjusting the amount of ink drawn out from the ink base roller, and in the preparatory stage before the printing machine starts the main printing, the opening degree of the ink key is determined according to the characteristics of the printing machine previously grasped. And an ink supply control means to be changed.

  This ink supply device changes the opening degree of the ink key in the arrangement direction of the ink key according to the characteristics of the printing press grasped in advance. Thereby, in the ink supply path, the opening degree of the corresponding ink key can be increased when the ink film thickness is thin, and the opening degree of the corresponding ink key can be decreased when the ink film thickness is thick. Therefore, in the ink supply path, it is possible to suppress variations in the ink film thickness in the ink key arrangement direction, that is, in the width direction of the printed matter. As a result, when the ink film is formed on the ink supply path in the printing preparation stage, it is possible to suppress variations in the ink film thickness in the width direction of the printed matter in the ink supply path.

  As a preferred aspect of the present invention, in the ink supply device, the ink supply control means uses a density distribution in the arrangement direction of the ink keys of the printed matter printed by the printer as a characteristic of the printer. desirable. Since the density distribution has a high correlation with the ink film thickness, by representing the characteristics of the printing press with the density distribution of the printed material in the ink key arrangement direction, the ink film thickness variation in the width direction of the printed material in the ink supply path Can be suppressed more effectively. The concentration distribution used here is preferably obtained under the condition that all the ink keys have the same opening degree.

  As a preferred aspect of the present invention, in the ink supply apparatus, the ink supply control means has a predetermined relationship between a preset opening degree of the ink key and a line ratio of a printed matter printed by the printing press. It is desirable to multiply the correction coefficient to set the opening of the ink key after the change. As a result, since the relationship between the opening degree of the ink key and the line ratio of the printed matter printed by the printing press can be used, the opening degree of the ink key can be easily set. The opening degree of the ink key is set for each ink key.

  As a preferred aspect of the present invention, in the ink supply device, the ink supply control means supplies a first amount of ink to the ink supply path when no ink is present in the ink supply path of the printing press. The opening degree of the ink key is changed at least one of the printing preparation and the second printing preparation for supplying ink according to the pattern to be printed when a predetermined amount of ink is present in the ink supply path It is desirable. As a result, the variation in the ink film thickness in the width direction of the printed material in the ink supply path can be suppressed, so that a printed material having a desired density can be obtained quickly. As a result, it is possible to reduce the waste paper generated in the trial printing and to shorten the time required for shifting to the main printing.

  In order to solve the above-described problems and achieve the object, the printing machine according to the present invention includes the ink supply device, a plate cylinder to which a printing plate to which ink is transferred from the ink supply device is attached, and the printing plate. A blanket cylinder to which a blanket to which the image line image of the ink formed thereon is transferred is attached, and a recording medium on which the line image on the blanket is transferred are disposed at a position facing the blanket cylinder. And an impression cylinder for pressing. Since this printing machine includes the ink supply device according to the present invention, when forming an ink film in the ink supply path in the printing preparation stage, it is possible to suppress variations in the ink film thickness in the width direction of the printed matter in the ink supply path. .

  In order to solve the above-described problems and achieve the object, an ink supply method according to the present invention is used to adjust the opening of an ink key that adjusts the amount of ink that the ink source roller draws from an ink reservoir provided in a printing press. A predetermined procedure for determining a correction coefficient for correcting the relationship between the opening degree of the ink key and the streak rate of the printed matter printed by the printing machine according to the characteristics of the printing machine; And a step of changing the opening degree of the ink key in the arrangement direction of the ink key by correcting the opening degree of the ink key by the correction coefficient in a preparatory stage before starting printing.

  In this ink supply method, a correction coefficient for correcting the relationship between the opening degree of the ink key and the line ratio of the printed matter printed by the printing machine is obtained according to the characteristics of the printing machine grasped in advance, and using this correction coefficient, The opening degree of the ink key is changed in the arrangement direction of the ink key. Thereby, in the ink supply path, the opening degree of the corresponding ink key can be increased when the ink film thickness is thin, and the opening degree of the corresponding ink key can be decreased when the ink film thickness is thick. Therefore, in the ink supply path, it is possible to suppress variations in the ink film thickness in the ink key arrangement direction, that is, in the width direction of the printed matter. As a result, when the ink film is formed on the ink supply path in the printing preparation stage, it is possible to suppress variations in the ink film thickness in the width direction of the printed matter in the ink supply path.

  As a preferred aspect of the present invention, in the ink method, it is desirable to use a density distribution in the arrangement direction of the ink keys of the printed matter printed by the printer as a characteristic of the printer. Since the density distribution has a high correlation with the ink film thickness, by representing the characteristics of the printing press with the density distribution of the printed material in the ink key arrangement direction, the ink film thickness variation in the width direction of the printed material in the ink supply path Can be suppressed more effectively.

  The present invention can suppress variations in the ink film thickness with respect to the width direction of the printed material in the ink supply path when the ink film is formed in the ink supply path in the printing preparation stage.

FIG. 1 is a schematic schematic configuration diagram of a sheet-fed printing press to which an ink supply apparatus according to this embodiment is applied. FIG. 2 is a schematic configuration diagram of the ink supply apparatus according to the present embodiment. FIG. 3 is an explanatory view showing an ink fountain and an ink base roller of the printing press according to the present embodiment. FIG. 4 is an explanatory diagram showing a part of the ink supply device of the printing press according to the present embodiment. FIG. 5 is a conceptual diagram showing changes in the ink film thickness on the printing plate from preparation for printing to full printing. FIG. 6 is a conceptual diagram illustrating an example of a line rate of a printed material that the printed material is about to be printed. FIG. 7A is a conceptual diagram illustrating a density distribution of a printed material obtained in the first print preparation. FIG. 7B is a schematic diagram illustrating the ink key opening degree corresponding to the line drawing rate. FIG. 8 is a flowchart showing a procedure for obtaining a correction coefficient of the ink supply method according to the present embodiment. FIG. 9 is a flowchart showing the procedure of the ink supply method according to the present embodiment.

  Hereinafter, the present invention will be described in detail with reference to the drawings. The present invention is not limited to the modes for carrying out the invention described below (hereinafter referred to as embodiments). In addition, constituent elements of the embodiments described below include those that can be easily assumed by those skilled in the art, those that are substantially the same, and those in a so-called equivalent range.

  FIG. 1 is a schematic schematic configuration diagram of a sheet-fed printing press to which an ink supply apparatus according to this embodiment is applied. FIG. 2 is a schematic configuration diagram of the ink supply apparatus according to the present embodiment. Hereinafter, as shown in FIG. 1, the ink supply apparatus 100 according to the present embodiment is a sheet-fed printing as a printing machine 1 that performs printing on a sheet S such as a film, art paper, or coated paper as well as paper for normal use. The case where it applies to a machine is demonstrated. In addition, the application object of this invention is not limited to the printing machine 1, For example, a rotary printing machine may be sufficient.

  The printing machine 1 is a sheet-fed printing machine, and is a so-called offset printing machine that includes a plate cylinder 8, a blanket cylinder 9, and an impression cylinder 10. The printing press 1 is controlled by the printing press control device 50. The printing machine 1 includes a sheet feeding unit 2 that feeds and feeds sheets S for printing one by one, a printing unit 3 that performs printing on the sheet S that is fed and conveyed along the traveling direction G, and printing. A paper discharge unit 4 that discharges the applied sheet S is provided.

  The paper feed unit 2 includes a paper feed tray 5 and a paper feed mechanism 6. The sheet feed table 5 is for stacking and placing sheets S, and the sheet feed mechanism 6 is for picking up and feeding the sheets S stacked on the sheet feed table 5 one by one from the top. Yes, it is composed of a separator (paper suction), a cam, a swing gripper and the like. The paper feed table 5 is controlled to move upward in the vertical direction corresponding to the supply of the sheet S so that the paper feed mechanism maintains a substantially constant positional relationship with the sheet S.

  The printing unit 3 includes a plurality of printing units 7 that print different colors to realize color printing. A plurality of printing units 7 are provided along the traveling direction G of the sheet S for each color to be printed. In the printing machine 1, for example, C (cyan), M (magenta), Y (yellow), and BL ( Four printing units 7 respectively corresponding to four different colors such as black) are provided.

  Each printing unit 7 includes the plate cylinder 8, the blanket cylinder 9, and the impression cylinder 10 as described above. The plate cylinder 8, the blanket cylinder 9, and the impression cylinder 10 are arranged so as to contact each other in this order from the upper side to the lower side in the vertical direction. The plate cylinder 8, the blanket cylinder 9 and the impression cylinder 10 are each formed in a cylindrical shape and provided so that the central axis thereof intersects the traveling direction G horizontally. The plate cylinder 8, the blanket cylinder 9, and the impression cylinder 10 are provided so as to be rotatable about their respective center axes.

  The plate cylinder 8 is provided with a printing plate for forming a printed image on its peripheral surface. Each printing unit 7 is moistened around the plate cylinder 8 with an ink supply device 100 (described later in FIG. 2) composed of a roller group for supplying ink to the image line portion of the printing plate and a non-image area. The dampening device 20 (refer FIG. 2) which consists of a water roller group for supplying water is provided. A blanket made of an elastic material is attached to the peripheral surface of the blanket cylinder 9. The ink supplied to the image line portion of the plate cylinder 8 is transferred to this blanket, and the blanket cylinder 9 transfers the printed image to the sheet S as a picture. The impression cylinder 10 applies a predetermined printing pressure in cooperation with the blanket cylinder 9. Here, the impression cylinder 10 is a so-called double cylinder having a diameter twice as large as that of the plate cylinder 8 and the blanket cylinder 9, and a claw device for holding the leading edge of the sheet S is provided in the groove portion on the circumferential surface (not shown). (Illustrated). Since the double cylinder structure is employed in the present embodiment, the claw device is provided at two locations substantially symmetrically across the central axis of the impression cylinder 10.

  Each printing unit 7 further includes an intermediate cylinder 11. The intermediate cylinder 11 is disposed on the upstream side of the impression cylinder 10 with respect to the traveling direction G of the sheet S and is in contact with the impression cylinder 10. Similar to the plate cylinder 8, the blanket cylinder 9, and the impression cylinder 10, the intermediate cylinder 11 is formed in a cylindrical shape and has a central axis that intersects the traveling direction G horizontally. It is provided rotatably. Similarly to the impression cylinder 10, the intermediate cylinder 11 is a so-called double cylinder having a diameter twice that of the plate cylinder 8 and the blanket cylinder 9, and the sheet S is formed in two groove portions provided on the peripheral surface. A claw device is provided for holding the tip.

  Each printing unit 7 is arranged such that each intermediate cylinder 11 is in contact with the impression cylinder 10 of the printing unit 7 adjacent to the upstream side in the traveling direction G of the sheet S. As shown in FIG. 1, in this embodiment, only the printing unit 7 located on the most upstream side with respect to the traveling direction G has an intermediate cylinder 11 of this double cylinder size on the upstream side of paper conveyance. In addition, a configuration is adopted in which the impression cylinder 10 conveys paper from the paper feeding unit 2 via a single cylinder type intermediate cylinder. The sheet S supplied from the paper supply unit 2 is first supplied between the blanket cylinder 9 and the impression cylinder 10 of the printing unit 7 located on the most upstream side, and then the intermediate cylinder of the downstream printing unit 7. By changing the nail device from 11 to the impression cylinder 10, it is conveyed through each printing unit 7, and the ink is transferred one after another on the way. However, the type and arrangement of the impression cylinder and the intermediate cylinder are not limited to this, and can be appropriately changed according to the required transport path design.

  The paper discharge unit 4 conveys and stacks the sheets S printed by the printing unit 3 in an aligned state. That is, the paper discharge unit 4 includes a chain gripper 12 that conveys the sheet S, a paper discharge tray 13 on which the printed sheets S are stacked, a fan device 14 that forms a downward airflow in the vicinity of the paper discharge tray 13, and paper A pad 16, a vacuum suction wheel device 17, a rear paper aligning device 18, and a width direction paper aligning device 19 are provided.

  The chain gripper 12 includes a pair of endless chains 15 that circulates and moves between an adjacent position of the impression cylinder 10 of the printing unit 7 on the most downstream side and an upper position of the paper discharge table 13, a gripper bar that connects the pair of grippers, and a gripper bar. And a gripper (claw device) 15a installed at a predetermined interval. The chain gripper 12 receives the sheet S from the impression cylinder 10 of the printing unit 7 and conveys the sheet S to a predetermined position above the sheet discharge tray 13.

  The paper discharge table 13 is suspended from a chain and configured to be movable in the vertical direction. The sheet discharge table 13 stacks and places the sheets S discharged from the chain gripper 12. When the upper surface height of the uppermost stage rises as the sheets S are stacked and kneaded, the discharge table 13 is continuously or stepwise vertically so that the falling distance of the sheets S becomes substantially constant. It is controlled to move downward in the direction.

  The fan device 14 has a plurality of fans arranged in a substantially rectangular shape, and moves the sheet S discharged from the chain gripper 12 above the discharge table 13 downward in the vertical direction by airflow control. The vacuum suction wheel device 17 reduces the traveling speed when the sheet S is dropped and controls the dropping posture. The vacuum suction wheel device 17 brakes the sheet S by applying a suction force to the upstream (rear) end in the traveling direction G of the sheet S.

  The paper pad 16, the rear paper aligning device 18, and the width direction paper aligning device 19 are positioned below the chain gripper 12 and above the paper discharge table 13, that is, between the chain gripper 12 and the paper discharge table 13. Provided. The paper pad 16 regulates the downstream (front) position in the traveling direction G of the sheet S, and a plurality of the paper pads 16 are provided along the width direction of the sheet S. The rear paper alignment device 18 regulates the upstream (rear) position in the traveling direction G of the sheet S, and is composed of a plurality of plate-like members extending in the vertical direction, and is attached to the vacuum suction wheel device 17 respectively. It is done. The width direction paper aligning device 19 aligns the positions of the sheets S in the width direction.

  In the printing machine 1 having the structure described above, the sheets S stacked on the paper feed tray 5 of the paper feed unit 2 are picked up one by one from the top by the paper feed mechanism 6 and supplied to the printing unit 7 of the printing unit 3. The The sheet S supplied to the printing unit 7 is conveyed through each printing unit 7 by being sequentially changed by a nail device (not shown) of the impression cylinder 10 and the intermediate cylinder 11 of each printing unit 7, and in the middle thereof. Ink is transferred one after another. In each printing unit 7, water is supplied from a dampening device 20 (see FIG. 2) to a non-image area of the printing plate attached to the peripheral surface of the plate cylinder 8, and then an ink supply device is applied to the image area of the printing plate. Ink is supplied from 100 (see FIG. 2). The printed image on the printing plate thus obtained is transferred to the blanket cylinder 9.

  The printed image transferred to the blanket cylinder 9 is transferred to the sheet S conveyed by the impression cylinder 10 and printing of one color is performed. This is repeated in each printing unit 7 for color printing. The color-printed sheet S is replaced from the impression cylinder 10 of the last printing unit 7 to the gripper 15a of the chain gripper 12. The sheet S conveyed by the gripper 15 a is removed from above the paper discharge tray 13, dropped, and stacked on the paper discharge tray 13. At this time, in order to prevent undried ink from appearing on the back of the upper sheet S, powder is sprayed on the sheet S in advance when the ink is conveyed by the gripper 15a. The sheets S stacked on the paper discharge tray 13 are aligned by the fan device 14, the vacuum suction wheel device 17, the paper pad 16, the rear paper alignment device 18, and the width direction paper alignment device 19, and then on the paper discharge table 13. Laminated.

  Next, the ink supply device will be described with reference to FIG. As shown in FIG. 2, the ink supply device 100 includes a plurality of rollers for supplying ink to the plate cylinder 8. The ink supply device 100 includes an ink fountain 101 as an ink reservoir, an intermediate ink roller group 102 composed of a plurality of rollers, and a plurality (four in this embodiment) of ink form rollers provided in contact with the plate cylinder 8. 103. In the ink supply device 100, the ink in the ink fountain 101 is transferred to the plate cylinder 8 after the intermediate ink roller group 102 and the plurality of ink form rollers 103 are sequentially transferred and appropriately kneaded.

  More specifically, the intermediate ink roller group 102 includes an ink base roller 104, a calling roller 105, a plurality of reciprocating rollers 106, and an ink kneading roller 107. The ink base roller 104 forms an ink film on the surface with the ink metered by the ink key of the ink fountain 101. The reciprocating roller 106 and the ink kneading roller 107 are provided in contact with the adjacent rollers, respectively, receive the ink supplied from the ink source roller 104 via a call roller 105 described later, and knead appropriately to sequentially adjoin. The ink is transferred to the reciprocating roller 106 and the ink kneading roller 107, and the ink is transferred to a plurality of ink forming rollers 103 in contact with the plate cylinder 8. The reciprocating rollers 106 reciprocate in the width direction (in the direction of the rotation axis of the reciprocating roller 106), thereby kneading ink and making the ink film formed on the surface uniform.

  The calling roller 105 is provided between the ink base roller 104 and a reciprocating roller 106a as a delivery roller located on the most upstream side with respect to the ink supply direction. The calling roller 105 swings back and forth between the ink source roller 104 and the reciprocating roller 106a, and alternately contacts the ink source roller 104 and the reciprocating roller 106a. That is, the calling roller 105 is rotatably provided at the other end of the swing lever 108 having a swing shaft at one end, and the swing shaft of the swing lever 108 moves in conjunction with a drive source such as the plate cylinder 8. By swinging through a mechanism such as a cam, the swing lever 108 and the ink source roller 104 and the reciprocating roller 106a can swing back and forth. Since the calling roller 105 is connected to a drive source such as the plate cylinder 8, the call roller 105 is swung at a constant speed ratio with respect to the rotation of the plate cylinder 8, and swings when the rotation speed of the plate cylinder 8 increases. The number of times (swinging speed), that is, the number of ink calls also increases. The ink taken out from the ink fountain 101 by the ink source roller 104 is supplied to the reciprocating roller 106a through the calling roller 105 that reciprocally swings between the ink source roller 104 and the reciprocating roller 106a.

  In the dampening device 20 provided below the ink supply device 100, a water source roller 22 that pumps out dampening water stored in the water boat 21 is provided. The metering roller 23 is provided so as to be able to contact, and the metering roller 23 is provided with a swim roller 24 so as to be able to contact. The water application roller 24 can come into contact with the plate cylinder 8, and an ink receiving roller 25 that can come into contact with the ink application roller 103 is provided in contact with the water application roller 24. In this case, the water source roller 22 can be driven by a motor (not shown), and the metering roller 23 can be driven. Further, the water application roller 24 can be driven by a motor, and the ink receiving roller 25 can be rotated together with the water application roller 24.

  Therefore, when each roller of the ink supply device 100 is rotated, the ink whose supply amount is adjusted by the ink source roller 104 is supplied to the reciprocating roller 106a via the calling roller 105, and is appropriately adjusted by the reciprocating roller 106 and the ink kneading roller 107. After being formed into a thin film, the ink is applied to the printing plate of the plate cylinder 8 from the ink form roller 103, the ink attached to the printing plate is transferred to the blanket cylinder 9, and a predetermined printing pressure is applied to the sheet S by the impression cylinder 10. By being applied, the ink of the blanket cylinder 9 can be transferred to the sheet S as a pattern. Then, each of the dampening devices 20 is in a state where the water roller 24 is in contact with the plate cylinder 8, the metering roller 23 is in contact with the water roller 24, and the ink receiving roller 25 is in contact with the ink roller 103. When the roller is rotated, the dampening water pumped up from the water boat 21 by the water source roller 22 is supplied to the swim roller 24 through the metering roller 23, and is supplied from the swim roller 24 to the plate cylinder 8. Can do. Further, the ink is transferred from the ink form roller 103 to the ink receiving roller 25, and the fountain solution is transferred from the water form roller 24, so that emulsification of the ink and the fountain solution can be promoted.

FIG. 3 is an explanatory view showing an ink fountain and an ink base roller of the printing press according to the present embodiment. FIG. 4 is an explanatory view showing a part of the ink supply device of the printing press according to the present embodiment. The ink fountain 101 stores ink used for printing, and includes an ink key 109. The ink key 109 forms a space for storing ink together with the outer peripheral surface of the ink base roller 104. As shown in FIG. 3, a plurality of ink keys 109 (109 ₁ , 109 ₂ ,... 109 _n ) are arranged in the direction of the central axis (rotation axis) Zi of the ink source roller 104. The ink key 109 is configured to be able to swing about the swing axis Zc. As a result, the distance α to the ink base roller 104 can be changed. The ink key 109 can adjust the amount of ink that the ink source roller 104 draws from the ink fountain 101 by adjusting the distance α between the ink key 109 and the ink source roller 104. If the distance α between the ink key 109 and the ink source roller 104 is 0, the ink source roller 104 does not draw ink.

  In the present embodiment, the ink key 109 includes an ink key driving means (for example, a motor) that adjusts the distance α between the ink key 109 and the ink source roller 104 to adjust the amount of ink that the ink source roller 104 draws from the ink fountain 101. Or a hydraulic cylinder) 110 is attached. A part of the ink key driving means 110 is attached to the frame 111 of the printing press 1 shown in FIG. The ink key driving means 110 is controlled by the printing press controller 50. The ink source roller 104 draws ink from the ink fountain 101, and the ink of the ink fountain 101 is supplied to the calling roller 105 that contacts the ink source roller 104. The ink key driving means 110 adjusts the distance α between the ink key 109 and the ink source roller 104 in accordance with a command from the printing press controller 50, whereby the amount of ink drawn by the ink source roller 104 is adjusted.

  The printing press control apparatus 50 includes a processing unit 51 and a storage unit 52. Further, an input device (for example, a touch panel or a keyboard) 53 that is an input unit and a display device (for example, a display) 54 that is a display unit are connected to the printing press control apparatus 50. A command for controlling the printing press 1 can be input to the printing press control device 50 by the input device 53. Further, the printing press control apparatus 50 can display the operation menu of the printing press 1, the state of the printing press 1, and the like on the display device 54.

  The processing unit 51 includes a CPU (Central Processing Unit) and a memory, and implements the function by loading a program for realizing the function of the processing unit 51 into the memory and executing the program. Note that the function of the processing unit 51 may be realized by dedicated hardware. The storage unit 52 includes a nonvolatile memory such as a hard disk device, a magneto-optical disk device, and a flash memory, a volatile memory such as a RAM (Random Access Memory), or a combination thereof. The processing unit 51 includes a print control unit 51a and an ink supply control unit 51b. The print control unit 51 a governs overall control of the printing press 1. The ink supply control unit 51b is an ink supply control unit of the ink supply apparatus 100, and adjusts the opening degree of the ink key 109 in the arrangement direction of the ink key 109 according to the characteristics of the printing machine 1 grasped in advance.

  FIG. 5 is a conceptual diagram showing changes in the ink film thickness on the printing plate from preparation for printing to full printing. FIG. 6 is a conceptual diagram illustrating an example of a line rate of a printed material that the printed material is about to be printed. FIG. 7A is a conceptual diagram illustrating a density distribution of a printed material obtained in the first print preparation. FIG. 7B is a schematic diagram illustrating the ink key opening degree corresponding to the line drawing rate. 6 and 7-1 show the distribution of the image line ratio and the density (optical density) D of the printed matter in the width direction of the printed matter (the direction orthogonal to the transport direction of the printed matter and the arrangement direction of the ink keys 109). . The vertical axis in FIGS. 6 and 7-1 is the image line rate and the density D, respectively, and the horizontal axis indicates the distance (width direction distance) L in the width direction of the printed matter. 0 on the horizontal axis is the operating side of the printing press 1, and Le is the driving side.

  When there is no ink in the ink supply path (from the ink base roller 104 to the plate cylinder 8) of the ink supply apparatus 100, the printing machine 1 executes the first printing preparation for supplying a predetermined amount of ink to the ink supply path. To do. When a predetermined amount of ink is present in the printing path, the printing machine 1 executes a second printing preparation for supplying ink according to the pattern to be printed. In the example shown in FIG. 5, the first print preparation (QSI-1) starts at time t = 0. At this time, the ink supply controller 51b of the printing press controller 50 shown in FIG. 4 opens the ink key 109 to a predetermined opening and supplies ink from the ink fountain 101 to the ink base roller 104. The ink supply control unit 51b sets the opening degree of all the ink keys 109 to the same size in the arrangement direction of the ink keys 109. Then, the ink supply control unit 51b starts the operation of the printing press 1 with the plate cylinder 8 and the blanket cylinder 9 separated.

  When the printing press 1 starts operation, the ink base roller 104 draws ink from the ink fountain 101 and reaches the plate cylinder 8 through the ink supply path. When the ink is not on the printing plate attached to the plate cylinder 8, the ink film thickness T on the printing plate is 0 (time t = 0 to t1), but the printing with the ink attached to the plate cylinder 8 is performed. When supplied to the plate, the ink film thickness T on the printing plate begins to rise (time t = t1). Here, in the first print preparation, the density of the printed material is a predetermined density (reference density) Db set in advance as a target value. The reference density Db is set in advance, and is usually compared with the density measured with a solid patch. When the first printing preparation is continued for a predetermined time (time t = t2), the ink supply control unit 51b starts the second printing preparation (QSI-2) (time t = t2).

  In the second printing preparation, the printing press 1 supplies ink corresponding to the line ratio of the printed matter to be printed to the printing plate attached to the plate cylinder 8. For example, as shown in FIG. 6, the ink supply control unit 51b adjusts the opening degree of each ink key 109 when the line ratio of the printed material to be printed is changing in the width direction of the printed material. To do. Thus, the ink is supplied to the ink source roller 104 so that the ink corresponding to the line drawing ratio of the printed material to be printed is supplied to the printing plate.

  When a predetermined time has elapsed since the start of the second printing preparation, an ink film thickness corresponding to the image line ratio of the printed material to be printed is obtained (time t = t3). Then, the printing control unit 51a of the printing press control apparatus 50 shown in FIG. 4 starts trial printing at time t = t4. When it is confirmed that the desired printed matter can be obtained by the trial printing, the printing control unit 51a starts the main printing (printing on the regular paper) (time t = t5). Note that the main printing is printing for printing a printed material as a product.

  For example, if printing is performed at the time when the first print preparation is completed, as shown by the solid line in FIG. 7A, all the reference density Db should be obtained in the width direction of the printed matter. However, depending on the characteristics of the printing press 1, as indicated by the dotted line A in FIG. 7A, the density D at the center of the printed material (width direction distance L = Lc) is the lowest, As shown, the density may gradually decrease in the width direction of the printed matter. Then, in the trial printing, it is necessary to close the ink key 109 for a portion higher than the reference density Db to lower the density, and for the portion lower than the reference density Db to open the ink key 109 to increase the density. As a result, the paper (recording medium) required for the trial printing increases, the amount of damaged paper (paper discarded without becoming a product) increases, and the start of the main printing is delayed.

  In this embodiment, in order to solve this problem, for example, in the first printing preparation, the characteristics of the printing press 1 are grasped in advance, and the opening degree of the ink key 109 is set according to the grasped characteristics. 109 is changed in the array direction. Thus, for example, the opening of the ink key 109 arranged in the portion is increased for a portion where the density is lower than the reference density Db, and the portion where the density is higher than the reference density Db is set in that portion. The opening degree of the ink key 109 to be arranged is made smaller, and the first printing preparation is executed. As a result, in the first printing preparation, since the ink film thickness variation in the width direction of the printed matter in the ink supply path can be suppressed, the reference density Db can be achieved in the entire width direction of the printed matter, and the density variation is suppressed. Is done. For this reason, since the adjustment of the ink key 109 is minimally necessary for the trial printing, the paper required for the trial printing can be minimized and the process can be promptly shifted to the main printing, thereby improving the productivity.

  For example, when the printing machine 1 has a characteristic as indicated by A in FIG. 7A, when a printed matter having a line drawing ratio ρ in the width direction as shown in FIG. The ink key opening Op was adjusted as indicated by the dotted line -2. However, in this embodiment, the characteristics of the printing press 1 (variation in ink film thickness in the width direction) are grasped in advance, and the ink key opening is adjusted in the width direction based on the characteristics. As a result, in this embodiment, the ink key opening Op is adjusted as shown by the solid line in FIG. As described above, in the present embodiment, the ink key opening Op is adjusted in consideration of the characteristics of the printing press 1, and therefore, variation in the ink film thickness in the width direction of the printed matter in the ink supply path is suppressed.

The opening degree of each ink key 109 is set according to the line drawing ratio ρ of the printed matter. If the opening degree of the ink key 109 (ink key opening degree) is Op_n (n is the number of each ink key 109), the ink key opening degree Op_n is a function of the drawing rate ρ (drawing rate−ink key opening conversion function) f (ρ ) Can be represented by the formula (1). That is, the relationship between the ink key opening Op_n and the image line ratio ρ of the printed matter printed by the printing machine 1 is expressed by Expression (1). Note that the image line ratio-ink key opening conversion function f (ρ) varies depending on the type of recording medium and the type of printing press.
Op_n = f (ρ) (1)

In the present embodiment, as a characteristic of the printing machine 1, the density distribution of the printed material in the width direction of the printed material (that is, the arrangement direction of the ink keys 109) is used. The ink key shown in Formula (1) according to the difference (density difference) ΔD (= D_r−Db) between the actual density (actual density) D_r and the reference density Db of the printed matter obtained by the first printing preparation. The relationship between the opening degree Op_n and the image line ratio ρ of the printed matter printed by the printing machine 1 is corrected. In the present embodiment, a correction coefficient k is obtained for each ink key 109 so that the density difference ΔD becomes 0, and this correction coefficient k is calculated as a line-ratio-ink key opening conversion function f (ρ for each ink key 109. ) To correct the ink key opening Op_n as shown in equation (2).
Op_n = k × f (ρ) (2)

  For example, the correction coefficient k is set to a value smaller than 1 for a part having a density higher than the reference density Db, and the correction coefficient k is set to a value greater than 1 for a part having a density lower than the reference density Db. The portion having the same density as the reference density Db is set to 1. Thus, since the ink key opening Op_n is set by multiplying the image ratio / ink key opening conversion function by the correction coefficient k, the ink key opening Op_n can be easily set. In addition, there is an advantage that an existing image ratio-ink key opening degree conversion function can be used.

  The correction coefficient k may be, for example, the ratio Db / D_r between the reference density Db and the actual density D_r. The correction coefficient k may be obtained by repeating printing while changing the correction coefficient k of each ink key 109 so that the density of the printed matter becomes the reference density Db. The correction coefficient k may be set for each ink key 109, or may be set for each ink key group by using a plurality of ink keys 109 as one ink key group.

  FIG. 8 is a flowchart showing a procedure for obtaining a correction coefficient of the ink supply method according to the present embodiment. For example, FIG. 8 shows a case where the characteristics of the printing press 1 shown in FIG. This is a procedure for obtaining a correction amount of the ink key opening Op_n after being installed. First, in step S101, the job of the printing press 1 shown in FIG. 1 is started, and plate exchange is executed in step S102.

  After the plate exchange is executed, in step S103, the print control unit 51a determines whether there is ink in the ink supply path of the printing machine 1. When it is determined No in step S103, that is, when the print control unit 51a determines that there is ink in the ink supply path of the printing machine 1, the ink supply method according to the present embodiment ends, and the pattern to be printed. The process proceeds to the second print preparation for supplying ink in accordance with the image line ratio.

  If it is determined Yes in step S103, that is, if the print control unit 51a determines that there is no ink in the ink supply path of the printing press 1, the process proceeds to step S104. In step S104, the print control unit 51a starts the first print preparation. At this time, the ink supply control unit 51b supplies ink to the ink source roller 104 shown in FIGS. 3 and 4 with the ink keys 109 shown in FIGS. 3 and 4 set to the same opening degree. The ink drawn from the ink fountain 101 to the ink base roller 104 is supplied to the printing plate attached to the plate cylinder 8 through the ink supply path. When ink is supplied to the plate, in step S105, the print control unit 51a starts printing.

  If a printed matter is obtained, the process proceeds to step S106. In step S106, the density D of the obtained printed matter is measured. This density D is the above-described actual density D_r, and is measured for each ink key 109 provided in each printing unit 7. Next, the process proceeds to step S107, and the correction amount (correction coefficient k in this embodiment) of the ink key opening Op_n of each ink key 109 is obtained. The method for obtaining the correction coefficient k is as described above. When the correction coefficient k is obtained in step S107, in step S108, the ink supply control unit 51b stores the correction coefficient k obtained in step S107 in the storage unit 52 of the printing press control apparatus 50 shown in FIG. Then, for example, the printing press control apparatus 50 performs the first print preparation again using the correction coefficient k stored in the storage unit 52.

  As a result, the ink film thickness formed in the ink supply path by the first printing preparation becomes substantially constant with respect to the arrangement direction of the ink keys 109, so that the reference density Db can be achieved in the entire width direction of the printed matter. In the printing process, the adjustment of the ink key 109 is minimized. As a result, the paper required for the trial printing is minimized, and the production can be promptly shifted to the main printing, thereby improving the productivity. In addition, in the second print preparation executed after the first print preparation, it is possible to quickly and accurately form the ink film thickness according to the image streak rate of the printed material to be printed.

  Even if the second printing preparation is executed after the first printing preparation, the ink from the first printing preparation is mainly used if it is the first few sheets of printed matter. Therefore, the correction amount can be obtained using this. In this case, the second print preparation is executed after step S104, and the correction amount is obtained using the first few printed materials.

  FIG. 9 is a flowchart showing the procedure of the ink supply method according to the present embodiment. FIG. 9 shows the procedure of the ink supply method when the correction amount of the ink key opening Op_n has already been obtained and stored in the storage unit 52 by the procedure shown in FIG. First, in step S201, the job of the printing press 1 shown in FIG. 1 is started, and plate exchange is executed in step S202.

  After the plate replacement is executed, in step S203, the print control unit 51a determines whether ink is present in the ink supply path of the printing machine 1. If it is determined Yes in step S203, that is, if the print control unit 51a determines that there is no ink in the ink supply path of the printing press 1, the process proceeds to step S204. In step S204, the ink supply controller 51b sets the ink key opening Op_n. In the present embodiment, the ink supply control unit 51b reads the correction coefficient k corresponding to each ink key 109 from the storage unit 52, and sets each ink key opening Op_n using Expression (2). As described above, in the present embodiment, the correction coefficient k is stored in the storage unit 52, and the ink supply control unit 51b automatically sets the opening of the ink key 109 when the first print preparation is executed. It is not necessary for a person to correct the opening degree of the ink key 109, and the work load is reduced.

  In step S205, the ink supply control unit 51b adjusts the opening of each ink key 109 of the ink key driving unit 110 shown in FIG. 4 so that the set ink key opening Op_n is obtained. Thereafter, the process proceeds to step S206, and the print control unit 51a starts the first print preparation.

  When the first printing preparation is executed for a predetermined time and ink has spread over the ink supply path, the process proceeds to step S207. In step S207, the print control unit 51a starts the second print preparation. When the second print preparation is completed, the print control unit 51a executes the trial printing, and then executes the main printing in step S208. When it is determined No in step S203, that is, when the print control unit 51a determines that there is ink in the ink supply path of the printing press 1, the process proceeds to step S207, and the print control unit 51a prepares for the second printing. Start. When the second print preparation is completed, the print control unit 51a executes the trial printing, and then executes the main printing in step S208.

  In the present embodiment, the ink key opening Op_n is corrected according to the characteristics of the printing press 1 in the first printing preparation. However, the ink key opening Op_n is corrected in the second printing preparation as well as the first printing preparation. May be. In this case, for example, the ink key opening Op_n is corrected by multiplying the ink key opening Op_n determined according to the image line ratio of the printed matter to be printed by the correction coefficient k described above. If the ink key opening Op_n is corrected in accordance with the characteristics of the printing machine 1 in the second printing preparation in addition to the first printing preparation, the adjustment of the ink key 109 is minimized in the subsequent printing process. As a result, the paper required for the trial printing can be minimized, and the production can be promptly shifted to the main printing, thereby further improving the productivity.

  It should be noted that the correction of the ink key opening Op_n according to the characteristics of the printing press 1 is preferably executed at the preparation stage of the main printing, and more preferably executed before the trial printing. In this way, by changing the ink key opening Op_n according to the characteristics of the printing machine 1 before the final printing, more specifically, before the trial printing, the paper required for the trial printing can be minimized. Productivity is further improved because it is possible to move to the final printing promptly. The correction may be performed by at least one of the first print preparation and the second print preparation. This makes it possible to form a necessary ink film thickness in the width direction of the printed matter before trial printing. The correction is most preferably performed in both the first print preparation and the second print preparation. However, if the correction is executed in the first print preparation, the width of the printed material can be effectively increased. The necessary ink film thickness can be formed. Therefore, when the first print preparation and the second print preparation cannot be executed due to time or the like, it is preferable to execute the correction in the first print preparation. Further, in the present embodiment, the ink key opening Op_n may be corrected according to the characteristics of the printing press 1 even in the final printing. In this way, it is possible to realize an appropriate ink film thickness considering the characteristics of the printing press 1.

  In the present embodiment, the correction coefficient k is determined according to the characteristics of the printing machine (the density distribution of the printed matter in the width direction of the printed matter). It is roughly divided into three patterns A, B, and C shown in FIG. That is, the pattern (A) in which the density on the driving side of the printed material is the highest and the central part in the width direction is the lowest, the density on the operation side of the printed material is the highest, and the pattern gradually decreases as the driving side is advanced (B) In the pattern (C), the density on the drive side of the printed material is the highest, and the density gradually decreases as the operation proceeds.

  For example, the correction coefficient k of the ink key opening Op_n for each ink key 109 is obtained in advance according to these three patterns and stored in the storage unit 52. When starting a job in a state where there is no ink in the ink supply path, the density distribution of the printed matter immediately after executing the first printing preparation is obtained, and it is confirmed which of the above three patterns corresponds. . Then, the operator inputs a density distribution pattern closest to the density distribution in the width direction of the printed material to the printing press controller 50. Then, the ink supply control unit 51b reads the correction coefficient k corresponding to the input density distribution pattern from the storage unit 52, and corrects the ink key opening Op_n for each ink key 109. As described above, by previously storing the correction coefficient k corresponding to the density pattern in the storage unit 52 and using this, it is possible to reduce the trouble of obtaining the correction coefficient k.

  In this embodiment, at least when the blanket is replaced, the plate cylinder 8 or the blanket cylinder 9 is replaced, or the roller of the ink supply path is replaced, the correction coefficient k described above is obtained again. . Further, when it is predicted that a blanket sag or nip change has occurred, the above-described correction coefficient k may be obtained again. In the latter case, the correction coefficient k that takes into account the change over time from the time of the new article can be obtained, so that even when the change over time occurs, the ink film thickness can be made uniform.

  As described above, the ink supply apparatus, the printing machine, and the ink supply method according to the present invention provide an ink film for the width direction of the printed material in the ink supply path when the ink film is formed in the ink supply path in the printing preparation stage. This is useful for suppressing variations in thickness.

DESCRIPTION OF SYMBOLS 1 Printing machine 2 Paper feed part 3 Printing part 4 Paper discharge part 5 Paper feed stand 6 Paper feed mechanism 7 Printing unit 8 Plate cylinder 9 Blanket cylinder 10 Impression cylinder 11 Intermediate cylinder 12 Chain gripper 13 Paper discharge stage 14 Fan apparatus 17 Vacuum suction Vehicle device 25 Ink receiving roller 50 Printing press control device 51 Processing unit 51a Print control unit 51b Ink supply control unit 52 Storage unit 53 Input device 54 Display device 100 Ink supply device 101 Ink fountain 102 Intermediate ink roller group 103 Ink roller 104 Ink Original roller 105 Calling roller 106, 106a Reciprocating roller 107 Ink kneading roller 109 Ink key 110 Ink key driving means 111 Frame

Claims (7)

An ink key that is arranged in the direction of the rotation axis of an ink fountain roller that draws ink from an ink fountain provided in a printing press, and that adjusts the amount of ink that the ink fountain roller draws from the ink reservoir;
In the preparatory stage before the printing machine starts full-printing, ink supply control means for changing the opening of the ink key according to the characteristics of the printing machine grasped in advance,
An ink supply device comprising: The ink supply control means is
The ink supply device according to claim 1, wherein a density distribution of the printed matter printed by the printing machine in the arrangement direction of the ink keys is used as the characteristic of the printing machine. The ink supply control means is
The preset opening degree of the ink key is set by multiplying a predetermined correction coefficient by a predetermined relationship between the opening degree of the ink key and the line ratio of the printed matter printed by the printing press. The ink supply apparatus according to 2. The ink supply control means is
When there is no ink in the ink supply path of the printing press, the first printing preparation for supplying a predetermined amount of ink to the ink supply path, and when there is a predetermined amount of ink in the ink supply path The ink supply device according to any one of claims 1 to 3, wherein an opening degree of the ink key is changed at least one of a second printing preparation for supplying ink according to a pattern to be performed. An ink supply device according to any one of claims 1 to 4,
A plate cylinder to which a printing plate to which ink is transferred from the ink supply device is attached;
A blanket cylinder to which a blanket to which an image line image of the ink formed on the printing plate is transferred;
An impression cylinder that is disposed at a position facing the blanket cylinder and pressurizes a recording medium onto which a line image on the blanket is transferred;
A printing machine comprising: When adjusting the opening of the ink key that adjusts the amount of ink that the ink source roller draws from the ink reservoir provided in the printing press,
A procedure for obtaining a correction coefficient for correcting a relationship between a preset opening degree of the ink key and a line ratio of a printed matter to be printed by the printing machine according to characteristics of the printing machine,
In a preparatory stage before the printing machine starts full-printing, a procedure for changing the opening degree of the ink key in the arrangement direction of the ink key by correcting the opening degree of the ink key by the correction coefficient;
An ink supply method comprising:   The ink supply method according to claim 6, wherein a density distribution of the printed matter printed by the printing machine in the arrangement direction of the ink keys is used as the characteristic of the printing machine.

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