JP2004009618A - Method for resuming printing operation after printing freezing with printing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for resuming a printing operation after printing freezing with a printing machine capable of properly resuming without causing a handling sheet to be wound upward even after printing freezing. <P>SOLUTION: The method provides a process measuring a freezing time of printing, a process comparing the freezing time with a pre-established reference time and a process executing at least one of the two options of a blanket-rinsing with a blanket-rinsing device when the freezing time is longer than the reference time and an indication requesting for the blanket-rinsing with the blanket-rinsing device.The reference time is established based on the pattern area ratio of a printed matter. After the blanket is rinsed with the blanket-rinsing device, it is prohibited to change the feeding amount of an ink and damping water during the pre-established waiting period. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for resuming printing after printing is interrupted in a printing machine provided with a blanket cleaning device.
[0002]
[Prior art]
In such a printing machine, an ink supply device for adjusting the amount of ink supplied to the ink roller is provided. This ink supply device is equipped with a plurality of ink keys arranged in a direction perpendicular to the transport direction of the printing paper during printing, and the amount of ink supplied to the ink roller is adjusted by changing the opening of each ink key. Thereby, the supply amount of the ink finally supplied to the printing plate is adjusted.
[0003]
Further, such a printing machine has a dampening solution supply device for adjusting a supply amount of dampening solution onto the dampening solution roller. The dampening water supply device includes a dampening water supply unit including a watercraft that stores dampening water, a water supply roller that is rotated by driving a motor, and a printing plate that supplies the dampening water supplied by the water supply roller. And a water roller for transferring to a surface of the water. In such a dampening water supply device, the supply amount of dampening water supplied to the surface of the printing plate can be adjusted by changing the number of revolutions of the fountain roller.
[0004]
On the other hand, an area called a detection patch or a control strip is formed at a position corresponding to each of the above-described ink keys on the printing plate. Then, at the time of printing, the degree of opening of each ink key and the number of rotations of the fountain roller are adjusted by measuring the color density of the detection patch actually printed on the printing paper with a densitometer.
[0005]
Further, in such a printing apparatus, when printing of a certain pattern is completed and printing of the next pattern is performed, the blanket cylinder is cleaned using a blanket cleaning device.
[0006]
[Problems to be solved by the invention]
When printing is being performed in a printing press, printing may be temporarily interrupted for some reason such as a paper jam, a registration error, or a poor plate making. In such a case, there is a problem that the ink on the blanket dries, and the printing paper rolls up.
[0007]
SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and it is an object of the present invention to provide a printing machine capable of appropriately resuming printing without causing winding of printing paper even after printing is interrupted. The purpose is to provide a restart method.
[0008]
[Means for Solving the Problems]
The invention according to claim 1 is a method for resuming printing after printing is interrupted in a printing machine equipped with a blanket cleaning device, wherein the step of measuring the interrupting time when printing is interrupted, and the interrupting time and a preset reference time are provided. And when the interruption time is longer than the reference time, at least one of cleaning of a blanket by the blanket cleaning device or an indication that a blanket should be cleaned by the blanket cleaning device is executed. And a process.
[0009]
According to a second aspect of the present invention, in the first aspect, the reference time is set based on a picture area ratio of a printed matter.
[0010]
According to a third aspect of the present invention, in the first aspect, the reference time is set based on at least one of a type of ink, a type of printing paper, a temperature, and a humidity.
[0011]
According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, after the blanket is cleaned by the blanket cleaning device, the supply amount of ink or the wetness of the ink is maintained for a preset standby period. Prohibit changing the supply of water.
[0012]
According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, after the blanket is cleaned by the blanket cleaning device, the ink is supplied using the parameters before the blanket is cleaned. The quantity and supply of dampening solution are controlled.
[0013]
According to a sixth aspect of the present invention, in the invention of the fifth aspect, the parameter before the blanket is cleaned is a parameter when a printing state is in a steady state.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram of a printing machine to which the present invention is applied.
[0015]
This printing press records an image on a printing plate on which the image held on the first and second plate cylinders 11 and 12 is not recorded and makes a plate, and then applies the ink supplied to the printing plate to the first and second plates. Printing is performed by transferring the image onto the printing paper held on the impression cylinder 15 via the second blanket cylinders 13 and 14.
[0016]
This printing press includes a first plate cylinder 11 movable between a first printing position indicated by a solid line in FIG. 1 and an image recording position indicated by a two-dot chain line, and a second printing cylinder indicated by a solid line in FIG. And a second plate cylinder 12 movable between the position and the image recording position.
[0017]
An ink supply device 20a for supplying, for example, black (K) ink to the printing plate and a magenta (M) ink for the printing plate are provided around the first plate cylinder 11 moved to the first printing position. And a dampening solution supply device 21a, 21b for supplying dampening solution to the printing plate. In addition, around the second plate cylinder 12 that has moved to the second printing position, an ink supply device 20c for supplying, for example, cyan (C) ink to the printing plate, and yellow (Y) to the printing plate, for example. An ink supply device 20d for supplying the ink of this type and dampening water supply devices 21c and 21d for supplying a dampening solution to the printing plate are arranged. Further, around the first plate cylinder 11 or the second plate cylinder 12 that has moved to the image recording position, a plate supply unit 23, a plate discharge unit 24, an image recording device 25, and a development processing device 26 are arranged. Have been.
[0018]
The printing press includes a first blanket cylinder 13 provided to be able to contact the first plate cylinder 11, a second blanket cylinder 14 provided to be able to contact the second plate cylinder 12, and And an impression cylinder 15 provided so as to be able to abut on the first and second blanket cylinders 13 and 14 at different positions from each other, and a feeder for passing the printing paper supplied from the paper feeding unit 27 to the impression cylinder 15. A paper cylinder 16, a paper discharge cylinder 17 around which a chain 19 for discharging printed print paper received from the impression cylinder 15 to a paper discharge unit 28, and a detection patch (control strip) printed on the print paper And a blanket cleaning device 29.
[0019]
The first and second plate cylinders 11 and 12 are respectively connected to a plate cylinder moving mechanism (not shown), and the first or second printing position and the image recording position described above are driven by driving the plate cylinder moving mechanism. Reciprocate between and. Further, by driving a motor (not shown), the first plate cylinder 11 rotates in synchronization with the first blanket cylinder 13 at the first printing position, and the second plate cylinder 12 rotates at the second printing position. It is configured to rotate in synchronization with the second blanket cylinder 14. Further, a plate cylinder rotating mechanism (not shown) is provided in the vicinity of the image recording position, and when the first and second plate cylinders 11 and 12 are both moved to the image recording position, the plate cylinder rotates. It is configured to rotate by driving a rotation mechanism.
[0020]
A plate feeding section 23 and a plate discharging section 24 are arranged around the first plate cylinder 11 or the second plate cylinder 12 that has moved to the image recording position.
[0021]
The plate supply unit 23 includes a supply cassette 63 for storing a long roll-shaped printing plate on which no image is recorded in a light-tight state, and a leading end of the printing plate pulled out from the supply cassette 63 as a first plate. A guide member 64 and a guide roller 65 for guiding the surface of the cylinder 11 or the second plate cylinder 12 and a cutter 66 for cutting a long printing plate into a sheet-shaped printing plate are provided. ing. The first and second plate cylinders 11 and 12 are provided with a pair of holding claws (not shown) for holding the leading and trailing ends of the printing plate supplied from the plate supply unit 23. .
[0022]
The plate discharging unit 24 discharges the printing plate peeled off by the action of the pawl mechanism 73 for peeling the printing plate held on the first plate cylinder 11 or the second plate cylinder 12 after the printing is completed. It has a conveyor mechanism 69 for transporting to the cassette 68 and a discharge cassette 68.
[0023]
The leading end of the printing plate pulled out of the supply cassette 63 in the plate supply unit 23 is guided by a guide roller 65 and a guide member 64, and is held by one of the holding claws of the first plate cylinder 11 or the second plate cylinder 12. Can be Then, the first plate cylinder 11 or the second plate cylinder 12 is rotated by the drive of the plate cylinder rotating mechanism 30, and the printing plate is wound around the outer periphery of the first plate cylinder 11 or the second plate cylinder 12. Then, the rear end of the printing plate cut by the cutter 66 is held by the other holding claw. In this state, while the first plate cylinder 11 or the second plate cylinder 12 is rotated at a low speed, the printing held by the image recording device 25 on the outer peripheral portion of the first plate cylinder 11 or the second plate cylinder 12 is performed. The surface of the plate is irradiated with a modulated laser beam and an image is recorded.
[0024]
As shown in FIG. 2A, the printing plate P mounted on the outer peripheral portion of the first plate cylinder 11 has an image area 67a for printing with black ink, as shown in FIG. And an image area 67b for printing with magenta ink. Further, as shown in FIG. 2B, the printing plate P mounted on the outer peripheral portion of the second plate cylinder 12 has an image area 67c for printing with cyan ink as shown in FIG. And an image area 67d for printing with yellow ink. The image area 67a and the image area 67b are recorded at positions that are equally distributed (that is, 180 degrees apart from each other) when mounted on the outer peripheral portion of the first plate cylinder 11. Similarly, the image area 67c and the image area 67d are recorded at positions that are equally distributed (that is, 180 degrees apart from each other) when mounted on the outer peripheral portion of the second plate cylinder 12. You.
[0025]
Referring again to FIG. 1, as described above, around the first plate cylinder 11 that has moved to the first printing position, the ink supply devices 20 a and 20 b are provided around the first plate cylinder 11. An ink supply device 20c and an ink supply device 20d are arranged around the second plate cylinder 12 that has moved to the position. Each of these ink supply devices 20a, 20b, 20c and 20d (these are collectively referred to as “ink supply device 20”) has a plurality of ink rollers 71 and an ink supply unit 72, respectively.
[0026]
The ink rollers 71 of the ink supply devices 20a and 20b perform a swing operation by the action of a cam or the like (not shown). By this swinging operation, the ink supply device 20a or 20b is applied to an arbitrary image area of the two image areas 67a and 67b formed on the printing plate P held on the outer peripheral portion of the first plate cylinder 11. When the ink roller 71 is in contact, the ink can be supplied only to a necessary image area. Similarly, the ink rollers 71 of the ink supply devices 20c and 20d also perform a swinging operation by the action of a cam or the like (not shown). By this swinging operation, the ink supply device 20c or 20d is applied to an arbitrary image area of the two image areas 67c and 67d formed on the printing plate P held on the outer peripheral portion of the second plate cylinder 12. When the ink roller 71 is in contact, the ink can be supplied only to a necessary image area.
[0027]
FIG. 3 is a schematic side view of the ink supply unit 72 described above, and FIG. 4 is a plan view thereof. In FIG. 4, illustration of the ink 3 is omitted.
[0028]
The ink supply unit 72 includes an ink source roller 1 whose axial direction is oriented in the width direction of the printed matter (a direction orthogonal to the printing direction of the printing press), and L ink rollers divided in the width direction of the printed matter. Ink keys 2 (1), 2 (2),... 2 (L) (which are arranged in rows corresponding to In the specification, these are collectively referred to as “ink key 2”), and the ink 3 is stored in an ink fountain formed by the ink source roller 1 and the ink key 2. .
[0029]
On the back side of each ink key 2, there are L eccentric cams for pressing the ink keys 2 toward the surface of the ink source roller 1 in order to change the degree of opening of each ink key 2 with respect to the ink source roller 1. 4 are provided. Each of these eccentric cams 4 is connected via a shaft 5 to L pulse motors 6 for driving the eccentric cam 4 to rotate.
[0030]
When an ink key driving pulse is applied to the pulse motor 6, the eccentric cam 4 rotates about the shaft 5 by driving the pulse motor 6, and the pressing force applied to each ink key 2 is changed. The opening of the ink key 2 with respect to the ink source roller 1 is changed, and the amount of ink supplied to the printing plate is changed.
[0031]
The ink supply device 72 is connected to the ink storage unit 120 via an ink supply pipe. An ink pump 121 for pumping the ink is disposed in the ink supply pipe. For this reason, when it is determined that the ink in the ink fountain formed by the ink source roller 1 and the ink key 2 is insufficient when the ink shortage described later is detected, the ink reservoir 121 is driven by the ink pump 121 to drive the ink. Ink is supplied into the vase.
[0032]
Referring again to FIG. 1, dampening water supply devices 21 a, 21 b, 21 c and 21 d (hereinafter collectively referred to as “fountain solution supply device 21”) are applied to the printing plate P by the ink supply device 20. A dampening solution is supplied to the printing plate P before supplying the ink. Of these dampening water devices 21, the dampening water supply device 21a is in the image area 67a in the printing plate P, the dampening water supply device 21b is in the image region 67b in the printing plate P, and the dampening water supply device 21c is in the printing region. The dampening solution supply device 21d supplies dampening water to the image region 67c of the printing plate P and the image region 67d of the printing plate P, respectively.
[0033]
FIG. 5 is a schematic side view of the dampening water supply device 21b described above.
[0034]
The dampening water supply device 21b is supplied by a dampening water supply unit including a watercraft 31 that stores dampening water, a damping roller 32 that is rotated by driving a motor (not shown), and a damping roller 32. It has two water rollers 33 and 34 for transferring dampening water to the surface of the printing plate mounted on the outer peripheral portion of the first plate cylinder 11. In this dampening water supply device, the supply amount of dampening water supplied to the surface of the printing plate can be adjusted by changing the number of revolutions of the fountain roller 32.
[0035]
The other three dampening water supply devices 21a, 21c, 21d have the same configuration as the dampening water supply device 21b.
[0036]
Referring to FIG. 1 again, a developing device 26 is disposed below the first plate cylinder 11 or the second plate cylinder 12 that has moved to the image recording position. The developing device 26 has a developing unit, a fixing unit, and a diaphragm unit, and is configured to be able to move up and down between a standby position indicated by a two-dot chain line and a developing position indicated by a solid line in FIG.
[0037]
When the printing plate P on which an image is recorded by the image recording device 25 is developed by the developing device 26, the printing plate P rotating together with the first plate cylinder 11 or the second plate cylinder is developed. Section, the fixing section, and the squeezing section.
[0038]
The first and second blanket cylinders 13, 14 provided so as to be able to contact the first and second plate cylinders 11, 12 have the same diameter as the first and second plate cylinders 11, 12. A blanket for ink transfer is mounted on the outer periphery. The first and second blanket cylinders 13 and 14 are configured to be able to freely contact and separate from the first and second plate cylinders 11 and 12 and the impression cylinder 15 by a cylinder insertion mechanism (not shown).
[0039]
The blanket cleaning device 29 provided between the first and second blanket cylinders 13 and 14 has a length attached to a path from an unwinding roll to a winding roll via a plurality of pressure rollers. The cleaning liquid is supplied to the cleaning cloth of a length, and the cleaning cloth is brought into contact with the first and second blanket cylinders 13 and 14 and then slid to thereby cause the first and second blanket cylinders 13 and 14 to slide. 14 is to clean the surface.
[0040]
The impression cylinder 15 provided so as to be in contact with the first and second blanket cylinders 13 and 14 has a diameter of the first and second plate cylinders 11 and 12 and the first and second blanket cylinders 13 and 14. It has a half diameter. Further, the impression cylinder 15 has a gripper (not shown) for holding and transporting the leading end of the printing paper.
[0041]
The paper feed cylinder 16 arranged adjacent to the impression cylinder 15 has the same diameter as the impression cylinder 15. The paper feed cylinder 16 holds and conveys the leading end of the print paper supplied one by one from the paper feed unit 27 by a gripper (not shown) by a suction board 74 that reciprocates. The leading end of the printing paper held by the gripper is held by the gripper of the impression cylinder 15 when the printing paper is transferred from the paper feed cylinder 16 to the impression cylinder 15.
[0042]
Further, the paper discharge cylinder 17 disposed adjacent to the impression cylinder 15 has the same diameter as the impression cylinder 15. The paper discharge cylinder 17 has a structure in which a pair of chains 19 are wound around both ends thereof, and grippers 41 (described later) are disposed on connecting members (not shown) that connect the pair of chains 19. . The leading end of the printing paper held by the gripper of the impression cylinder 15 is held by one of the grippers 41 of the discharge cylinder 17 when the printing paper is transferred from the impression cylinder 15 to the discharge cylinder 17. Then, the printing paper is conveyed to the paper output unit 28 and discharged after the color density of the detection patch printed thereon is measured by the imaging unit 40 as the chain 19 moves.
[0043]
The paper feed cylinder 16 is connected to a drive motor via a belt (not shown). The paper feed cylinder 16, the impression cylinder 15, the paper discharge cylinder 17, and the first and second blanket cylinders 13 and 14 are connected by gears attached to their ends. Further, the first blanket cylinder 13 and the first plate cylinder 11 moved to the first printing position, and the second blanket cylinder 14 and the second plate cylinder 12 moved to the second printing position, They are connected by gears attached to their ends. Therefore, by the driving of a drive motor (not shown), these paper feed cylinder 16, impression cylinder 15, discharge cylinder 17, first and second blanket cylinders 13, 14, and first and second plate cylinders 11, 12 are moved. Rotate in synchronization with each other.
[0044]
FIG. 6 is a schematic side view showing the imaging unit 40 for measuring the color density of the detection patch printed on the printing paper, together with the chain 19 described above.
[0045]
The pair of chains 19 are endlessly stretched between both ends of the paper discharge cylinder 17 shown in FIG. 1 and the pair of large-diameter sprockets 18. As described above, the grippers 41 for gripping and transporting the leading end of the printing paper S are disposed on the connecting members (not shown) that connect the pair of chains 19.
[0046]
The length of the pair of chains 19 is an integral multiple of the circumference of the paper discharge cylinder 17, and the arrangement interval of the grippers 41 on the chain 19 is equal to the circumference of the paper discharge cylinder 7. Is set to Each gripper 41 is configured to open and close in synchronization with a gripper provided on the paper discharge cylinder 7 by a cam mechanism (not shown), receives the printing paper S from the paper discharge cylinder 7, and rotates the chain 19. Then, after the printing paper S is conveyed, it is discharged onto the paper discharge unit 28.
[0047]
When the printing paper S is transported, only the leading end of the printing paper S is gripped and transported by the gripper 41, so that the rear end of the printing paper S is transported without being fixed. For this reason, at the time of this conveyance, the printing paper S flaps, which hinders the operation of the imaging unit 40 described later for measuring the color density of the detection patch. For this reason, this printing machine is provided with a suction roller 43 for stabilizing the conveyance state of the printing paper S in front of the paper discharge unit 28.
[0048]
The suction roller 43 is composed of a hollow roller having a large number of fine suction holes on its surface, and the hollow portion is connected to a vacuum pump (not shown). The suction roller 43 is arranged so that its axis is parallel to the gripper 41 spanned between the pair of chains 19, and its top is located at substantially the same height as the lower passage position of the chain 19.
[0049]
The suction roller 43 is configured to be driven to rotate in accordance with the passing speed of the gripper 41 or to be rotatable. Therefore, when the printing paper S passes over the suction roller 43, the printing paper S is conveyed while being sucked on the surface of the suction roller 43. I can't beat. Note that, instead of the suction roller 43, a suction plate member that suctions the printing paper S in a planar manner may be used.
[0050]
The imaging unit 40 includes an illumination unit 44 that illuminates the transported printing paper S, and an imaging unit 45 that captures a detection patch on the printing paper S illuminated by the illumination unit 44 and measures the color density. Consists of The illuminating unit 44 is arranged along the suction roller 43, is composed of a plurality of linear light sources that illuminate the printing paper S on the suction roller 43, and is provided between the vertical running regions of the chain 19.
[0051]
The imaging unit 45 includes a housing 46 for shielding light and dust, a mirror 49, a lens 48, and a CCD line sensor 47 arranged inside the housing. The imaging unit 45 captures an image of the printing paper S on the suction roller 43 through a slit of the illumination unit 44, and the incident light of the image folded by the mirror 49 passes through the lens 48 and passes through the CCD line sensor 47. Is received at.
[0052]
FIG. 7 is a block diagram showing a main electrical configuration of the printing press. The printing press includes a control unit 140 including a ROM 141 in which operation programs necessary for controlling the apparatus are stored, a RAM 142 in which data and the like are temporarily stored at the time of control, and a CPU 143 for executing a logical operation. The control unit 140 controls the ink supply device 20, the dampening solution supply device 21, the image recording device 25, the development processing device 26, the blanket cleaning device 29, the imaging unit 40, the first and second via the interface 144. It is connected to a drive circuit 145 that generates a drive signal for a drive unit or the like in the blanking mechanism of the blanket cylinders 13 and 14. The printing press is controlled by the control unit 140, and executes a plate making operation and a printing operation described later.
[0053]
Next, plate making and printing operations by this printing machine will be described. FIG. 8 is a flowchart showing the outline of the plate making and printing operations performed by the printing press. Note that the printing and plate making operations are performed when multicolor printing is performed on the printing paper S with four color inks of yellow, magenta, cyan, and black.
[0054]
First, a plate making process of recording an image on the printing plate P on the first and second plate cylinders 11 and 12 and performing a developing process is executed (step S1). This plate making process is performed according to a process shown in a flowchart of FIG. 9 as a subroutine.
[0055]
That is, first, the first plate cylinder 11 is moved to an image recording position indicated by a two-dot chain line in FIG. 1 (step S11).
[0056]
Next, the printing plate P is supplied to the outer periphery of the first plate cylinder 11 (Step S12). The printing plate P is supplied by holding the leading end of the printing plate P pulled out from the supply cassette 63 and the rear end of the printing plate P cut by the cutter 66 with a pair of holding claws (not shown).
[0057]
Subsequently, an image is recorded on the printing plate P held on the outer periphery of the first plate cylinder 11 (Step S13). This image is recorded by rotating the first plate cylinder 11 at a low speed and irradiating the printing plate P held on the outer periphery of the first plate cylinder 11 with a modulated laser beam from the image recording device 25. Be executed.
[0058]
Next, the printing plate P on which the image is recorded is developed (Step S14). The developing process is performed by raising the developing device 26 from a standby position indicated by a two-dot chain line in FIG. 1 to a developing position indicated by a solid line, and then developing the printing plate P that rotates together with the first plate cylinder 11. This is performed by sequentially contacting the fixing unit, the fixing unit, and the squeezing unit.
[0059]
Upon completion of the developing process, the first plate cylinder 11 is moved to a first printing position indicated by a solid line in FIG. 1 (step S15).
[0060]
Subsequently, a plate making process for the printing plate P held on the outer periphery of the second plate cylinder 12 is executed by the same operation as in steps S11 to S15 (steps S16 to S20). Then, when the plate making on the printing plate P held on the outer periphery of the first and second plate cylinders 11 and 12 is completed, the plate making process is completed.
[0061]
Referring to FIG. 8 again, when the plate making process is completed, a printing process of performing printing on printing paper S using printing plates P on first and second plate cylinders 11 and 12 is performed (step S2). . This printing process is performed as follows.
[0062]
That is, first, each dampening solution supply device 21 and each ink supply device 20 are brought into contact only with the corresponding image area of the printing plate P held on the first and second plate cylinders 11 and 12. As a result, dampening water and ink are supplied to the image areas 67a, 67b, 67c, and 67d from the corresponding dampening water supply devices 21 and ink supply devices 20, respectively. Then, the ink supplied to the printing plate P is transferred to corresponding areas of the first and second blanket cylinders 13 and 14.
[0063]
Then, the printing paper S is supplied to the paper feed cylinder 16. The printing paper S is passed from the paper feed cylinder 16 to the impression cylinder 15. In this state, when the impression cylinder 15 continues to rotate, the impression cylinder 15 has a diameter of １ ／ of the first and second plate cylinders 11 and 12 and the first and second blanket cylinders 13 and 14. Thus, black and cyan inks are transferred to the printing paper S held on the outer peripheral portion of the impression cylinder 15 in the first rotation, and magenta and yellow inks are transferred in the second rotation.
[0064]
In this way, the leading end of the printing paper S on which the printing of four colors has been completed is transferred from the impression cylinder 15 to the discharge cylinder 17. The printing paper S on which the printing of the four colors has been completed is conveyed toward the paper output unit 28 by driving the pair of chains 19, and after the color density of the detected patch is measured by the imaging unit 40, 28.
[0065]
When the printing process is completed, the printing plate P used for printing is discharged (step S3). In order to discharge the printing plate P, first, the first plate cylinder 11 is moved to an image recording position indicated by a two-dot chain line in FIG. Then, the first plate cylinder 11 is rotated counterclockwise, and the end of the printing plate P held on the first plate cylinder 11 is peeled off by the claw mechanism 73. It is guided by 69 and discharged into the discharge cassette 68. Then, after returning the first plate cylinder 11 to the first printing position, the second plate cylinder 12 is moved from the second printing position to the image recording position, and by performing the same operation as described above, The printing plate P held on the second plate cylinder 12 is discharged into the discharge cassette 68.
[0066]
When the printing plate P discharge process is completed, the first and second blanket cylinders 13 and 14 are cleaned by the blanket cylinder cleaning device 29 (Step S4).
[0067]
When the cleaning of the first and second blanket cylinders 13 and 14 is completed, it is confirmed whether or not to perform a printing operation for another printed matter (step S5). When performing another printing operation, the operations of steps 1 to 4 are repeated.
[0068]
When the printing operation has been completed, the ink is washed (step S6). The cleaning of the ink is performed by removing and cleaning the ink adhered to the ink roller 71 and the ink supply unit 72 in each ink supply device 20 by an ink cleaning device (not shown) provided in each ink supply device 20. You.
[0069]
When the ink washing process is completed, all the processes are completed.
[0070]
In the printing apparatus having the above-described configuration, in order to control the amount of ink to be supplied to the printing plate P, a detection patch called a management scale or the like is used.
[0071]
FIG. 10 is an explanatory diagram showing a first detection patch (first control strip) 101 and a second detection patch (second control strip) 102 printed on the printing paper S after printing is completed. is there.
[0072]
These first and second detection patches 101 and 102 are printed in an area between one end of the printing paper S and an end of the image area on the printing paper S. The first detection patch 101 and the second detection patch 102 are divided into L areas divided in the width direction of the printed matter (the direction orthogonal to the printing direction by the printing machine), similarly to the ink keys 2 described above. Correspondingly, L pieces are arranged adjacent to each other. Among these first and second detection patches 101 and 102, those having a high halftone dot area ratio or solid patches are used as the first detection patches 101, and low halftone dot area ratios are used as the second detection patches 102. Things are used.
[0073]
In the above-described printing press, the image density of the first and second detection patches 101 and 102 is measured by the imaging unit 40. Then, based on the measured color densities of the first and second detection patches 101 and 102, the opening degree of each ink key 2 shown in FIGS. Control the supply. The supply amount of dampening water is controlled by changing the number of rotations of the water supply roller 32 shown in FIG. 5 based on the measured color densities of the first and second detection patches 101 and 102.
[0074]
Next, a method of resuming printing after printing is interrupted in the printing press according to the present invention will be described. FIG. 11 and FIG. 12 are flowcharts showing the printing restart operation after the printing is interrupted.
[0075]
When the printing step (step S2) shown in FIG. 8 is being executed, the steps shown in FIGS. 11 and 12 are executed as subroutines.
[0076]
In the printing step (step S2) shown in FIG. 8, first, it is determined whether or not printing is in a steady state (step S21). For example, whether or not the steady state has been reached is, for example, whether or not the color densities of the first and second detection patches 101 and 102 actually printed on the printing paper S have stabilized about 30 sheets continuously with respect to the reference density. It is determined according to
[0077]
If the printing is in a steady state, the parameters of the ink supply amount and the dampening solution supply amount at that time are stored in the RAM 142 shown in FIG. 7 (step S21). Here, the parameter of the ink supply amount is a parameter including information on the degree of opening of each ink key 2 with respect to the image printed on the printing paper S. Further, the parameter of the dampening water supply amount is a parameter including information on the number of rotations of the fountain roller 32 with respect to the image printed on the printing paper S.
[0078]
In this state, it is determined whether or not a print interruption command has been issued (step S23). If the printing is not interrupted, the process proceeds to step S35 to determine whether or not the necessary printing is completed. If the printing is not completed, the process returns to step S21 again. On the other hand, in this state, if printing is temporarily interrupted for some reason such as a paper jam, the interruption time t is measured by the control unit 140 shown in FIG. 7 (step S24). The measurement of the interruption time t is continued until a print restart command is issued (step S25). When a restart is instructed in step S25, the measurement of the interruption time t ends (step S26).
[0079]
The interruption time t is compared with a preset reference time t0 (where t0 is a time equal to or longer than zero) (step S27). If the interruption time t is shorter than the preset reference time t0, printing is restarted (step S29). Then, the process proceeds to step S35 to determine whether or not necessary printing is completed. If the printing is not completed, the process returns to step S21 again. On the other hand, if the interruption time t is longer than the preset reference time t0, the blanket is washed (step S28).
[0080]
In this blanket cleaning step, a blanket cleaning device 29 (see FIG. 1) disposed between the first and second blanket cylinders 13 and 14 is used, and is fed from an unwinding roll via a plurality of pressure rollers. A cleaning liquid is supplied to a long cleaning cloth stuck on a path leading to a take-up roll, and the cleaning cloth is brought into contact with the first and second blanket cylinders 13 and 14 and then slid. As a result, the surfaces of the first and second blanket cylinders 13 and 14 are cleaned.
[0081]
The above-described reference time t0 is set based on the pattern area ratio of the printed matter. That is, when the picture area ratio of the printed matter is large, the winding of the printing paper is likely to occur. Therefore, when the picture area ratio of the printed matter is large, the above-described reference time t0 is set short. As the pattern area ratio, the average pattern area ratio of the pattern region 103 (see FIG. 10) on the printing paper S may be adopted, or the maximum pattern area ratio of the pattern region 103 on the printing paper S is adopted. May be. This pattern area ratio may be stored in the RAM 142 or the like in the control unit 140 in advance, and the actual pattern area ratio on the printing paper S measured by the imaging unit 40 immediately before the interruption of printing is used as the pattern area ratio. You may.
[0082]
Further, the reference time t0 may be determined based on at least one of the type of ink, the type of printing paper, the temperature, and the humidity. In this case, the relationship between the type of ink, the type of printing paper, the temperature, the humidity, and the reference time t0 may be stored in the form of a look-up table or the like in the RAM 142 of the control unit 140 in advance.
[0083]
When the suspension time t is longer than the preset reference time t0, an indication that the blanket should be washed may be displayed instead of immediately washing the blanket. As this display, for example, a warning display on a CRT, lighting of a warning lamp, transmission of a warning sound, and the like can be adopted. When this display is made, the operator uses the blanket cleaning device 29 to clean the surfaces of the first and second blanket cylinders 13 and 14.
[0084]
When the blanket cleaning is completed, the parameters of the ink supply amount and the dampening solution supply amount stored in the RAM 142 are read (step S30). This parameter is used to adjust the supply amount of the ink and the supply amount of the dampening solution after the printing is restarted.
[0085]
The reason why the ink supply amount and the dampening water supply amount are controlled using the parameters before the blanket cleaning after the blanket cleaning is performed is as follows. That is, before blanket cleaning, a steady state is formed over a certain period of time, and in order to perform stable printing under the same conditions as before blanket cleaning, blanket cleaning is performed using parameters before blanket cleaning. This is because it is preferable to perform printing under the same conditions as in the steady state before cleaning.
[0086]
Next, the change of the supply amount of the ink and the supply amount of the dampening solution is prohibited (step S31). More specifically, the adjustment of the opening of the ink key 2 shown in FIGS. 3 and 4 and the adjustment of the number of rotations of the water supply roller 32 shown in FIG. 5 are prohibited.
[0087]
Immediately after washing the blanket, the color density of the image printed on the printing paper S decreases until a predetermined amount of ink is supplied onto the blanket again. Therefore, immediately after the blanket is washed, when the color density of the printed matter is measured to automatically control the ink supply amount and the dampening solution supply amount, the opening degree of the ink key 2 and the rotation speed of the water supply roller 32 are controlled. However, even if these are appropriate, there arises a problem that these are adjusted excessively. For this reason, after the blanket is washed, the adjustment of the opening of the ink key and the adjustment of the rotation speed of the water supply roller are prohibited until a predetermined standby time T has elapsed.
[0088]
In this state, printing is restarted (step S32). As described above, after the restart, the supply amount of the ink and the supply amount of the dampening solution are controlled using the parameters before the blanket cleaning.
[0089]
After the printing is restarted, the process waits for the standby time T to elapse (step S33). The standby period T is a time set in advance as a set number print time required to execute printing on a predetermined number of print sheets S. Then, when the standby time T has elapsed, the prohibition of the change of the supply amount of the ink and the supply amount of the dampening solution is released (step S34). Thereafter, the supply amount of the ink and the supply amount of the dampening solution are automatically controlled using the color densities of the first and second detection patches 101 and 102 on the printing paper S measured by the imaging unit 40. Is done.
[0090]
Thereafter, it is determined whether the necessary printing is completed (step S35). If the printing is not completed, the process returns to step S21 to repeat the above-described operation. When the necessary printing is completed, all the processes are completed.
[0091]
Each operation described above is executed under the control of the control unit 140 shown in FIG. The control unit 140 functions as control means for executing the above-described operations.
[0092]
In the above-described embodiment, the present invention is applied to the printing plate after recording the image on the printing plate in which the image held by the first and second plate cylinders 11 and 12 is not recorded and making the plate. A case has been described in which the present invention is applied to a printing machine that performs printing by transferring ink onto printing paper held on an impression cylinder 15 via first and second blanket cylinders 13 and 14, but the present invention is applied to other general machines. May be applied to a typical printing machine.
[0093]
【The invention's effect】
According to the first to third aspects of the present invention, the blanket cleaning device uses the blanket cleaning device when the printing suspension time is longer than the reference time, or the blanket cleaning device should display the blanket cleaning device. By executing at least one of the above, it is possible to appropriately resume printing even after the printing is interrupted, without causing the printing paper to wind up.
[0094]
According to the invention described in claim 4, since the blanket cleaning device prohibits the change of the supply amount of the ink or the supply amount of the dampening solution for a preset standby period after the blanket is cleaned, the blanket cleaning after the blanket cleaning. Even if the supply amount of the ink and the supply amount of the dampening solution are appropriate, it is possible to prevent the problem that these are further adjusted beforehand.
[0095]
According to the fifth and sixth aspects of the present invention, after the blanket is cleaned by the blanket cleaning device, the supply amount of the ink and the supply amount of the dampening solution are controlled using the parameters before the blanket is cleaned. Therefore, stable printing can be performed under the same conditions as before the blanket cleaning.
[Brief description of the drawings]
FIG. 1 is a schematic side view of a printing apparatus to which the present invention is applied.
FIG. 2 is an explanatory diagram showing an arrangement of an image area 67 on a printing plate P.
FIG. 3 is a schematic side view of an ink supply unit 72.
FIG. 4 is a plan view of an ink supply unit 72.
FIG. 5 is a schematic side view of a dampening water supply device 21b.
FIG. 6 is a schematic side view showing the imaging unit 40 together with the chain 19.
FIG. 7 is a block diagram illustrating a main electrical configuration of the printing apparatus.
FIG. 8 is a flowchart illustrating an outline of plate making and printing operations performed by the printing apparatus.
FIG. 9 is a flowchart showing a plate making process.
FIG. 10 is an explanatory diagram showing a first detection patch 101 and a second detection patch 102.
FIG. 11 is a flowchart illustrating a print resuming operation after printing is interrupted.
FIG. 12 is a flowchart illustrating a print resuming operation after printing is interrupted.
[Explanation of symbols]
REFERENCE SIGNS LIST 1 ink source roller 2 ink key 3 ink 4 eccentric cam 5 shaft 6 pulse motor 11 first plate cylinder 12 second plate cylinder 13 first blanket cylinder 14 second blanket cylinder 15 impression cylinder 16 feed cylinder 17 discharge Paper cylinder 18 sprocket 19 chain 20 ink supply device 21 dampening solution supply device 23 plate supply unit 24 plate discharge unit 25 image recording device 26 development processing unit 27 paper supply unit 28 paper discharge unit 31 watercraft 32 water source roller 33 water roller 34 Water roller 40 imaging unit 41 gripper 43 suction roller 44 illumination unit 45 imaging unit 47 CCD camera 48 lens 49 mirror 72 ink supply unit 101 first detection patch 102 second detection patch 120 ink storage unit 121 ink pump 140 control unit P Printing plate S Printing paper

Claims (6)

A method for resuming printing after printing is interrupted in a printing machine equipped with a blanket cleaning device,
Measuring the interruption time during which printing was interrupted;
Comparing the interruption time with a preset reference time;
When the interruption time is longer than the reference time, a step of performing at least one of cleaning of a blanket by the blanket cleaning device, and an indication that a blanket should be cleaned by the blanket cleaning device;
A method for resuming printing after interruption of printing in a printing press, comprising: The method according to claim 1, wherein the printing press resumes printing after interruption.
A printing restart method after printing is interrupted in a printing press, wherein the reference time is set based on a pattern area ratio of a printed material. The method according to claim 1, wherein the printing press resumes printing after interruption.
A method for resuming printing after interruption of printing in a printing press, wherein the reference time is set based on at least one of the type of ink, the type of printing paper, the temperature, and the humidity. A method according to claim 1, wherein the printing press resumes printing after interruption of printing.
A method of resuming printing after interruption of printing in a printing press, in which a change in an ink supply amount or a dampening solution supply amount is prohibited for a preset standby period after the blanket cleaning device cleans the blanket. 5. The method according to claim 1, wherein the printing is restarted after the printing is interrupted.
A method of resuming printing after printing is interrupted in a printing press, wherein after the blanket is washed by the blanket washing apparatus, the supply amount of ink and the supply amount of dampening solution are controlled using the parameters before the blanket was washed. 6. The method according to claim 5, wherein the printing press resumes printing after interruption.
A method for resuming printing after printing is interrupted in a printing press, wherein the parameter before cleaning the blanket is a parameter when the printing state is in a steady state.

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