JPH08174803A - Printing system - Google Patents

Abstract

PURPOSE: To provide a printing system in which the removal of a foreign matter and the discharge of a defective product can be automatically conducted. CONSTITUTION: This printing system comprises a design inspecting unit 22 for comparing a design to be printed with a design printed by a printing unit 4 to inspect, a foreign matter removing mechanism 12 for removing a foreign matter from the surface of a plate cylinder based on a defect occurring position coordinates calculated by the unit 22 when the print failure is detected by the unit 22, a rejecting unit 7 for discharging the defective print and a controller 23 for controlling the mechanism 12 and the unit 7 at the rear stage side of the unit 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing system suitable for fully automating an offset rotary printing press.

[0002]

2. Description of the Related Art As is well known, an offset rotary printing machine (hereinafter, simply referred to as "printing machine") comprises a cylindrical plate cylinder and a blanket cylinder, and supplies ink from the plate cylinder to the blanket cylinder. A predetermined pattern is printed by transferring the ink from the blanket cylinder to a web-shaped or sheet-shaped printing material continuously fed in one direction.

By the way, in such a printing machine, foreign matter such as so-called Hicky adheres to the plate cylinder and the blanket cylinder, which causes defective printing (scraping).
May occur. Conventionally, in order to check the occurrence of such a print defect, an operator regularly extracts the printed matter after printing and visually checks it.

When such a printing defect is found, the worker manually removes foreign matter on the body surface of the plate cylinder or the blanket cylinder by using a spatula or the like.

Further, in recent years, a mechanism for removing foreign matter is provided movably along the surface of the plate cylinder or blanket cylinder, and an operator operates the mechanism to move to a defective printing position. There is also used a semi-automatic removal device configured to move the tool to remove foreign matter from the body surface.

[0006]

However, the conventional offset printing machine as described above has the following problems. First, especially in the case of manual work, the foreign matter attached to the spatula may reattach to the body surface when the foreign matter is removed next time. Also, the work of removing foreign matter from the plate surface of the rotating plate cylinder or blanket cylinder is
There are risks. In addition, when printing defects occur due to dust adhering to the plate cylinder or blanket cylinder,
Not only in the case of manual work, but also in the case of removing the foreign matter by using the removing device, the work is time-consuming, and there is a problem that the operating rate of the equipment is reduced. Moreover, since defective prints occur continuously, all the printed matter until the troublesome foreign matter removal work is completed is defective, and for the reason of work efficiency, the printed matter before and after the removal work is performed. Is also removed as a defective product,
There is also a problem that the cost of defective products increases.

As described above, in the conventional printing machine, various problems have occurred because the inspection process other than the printing process and the process of separating defective products from non-defective products are not automated. It was desired to automate the above. The present invention has been made in view of the above points, and an object of the present invention is to provide a printing system that can automatically remove foreign substances and discharge defective products to achieve full automation.

[0008]

The invention according to claim 1 is
A printing system for offset-printing a specified pattern on a web-shaped or sheet-shaped printing medium continuously fed in one direction by a printing unit including a cylindrical plate cylinder and a blanket cylinder. In the printing system, the pattern provided on the subsequent stage of the printing unit is compared with the predetermined pattern to be printed by the pattern printed on the object to be printed by the printing unit. The pattern generation means for calculating the defect occurrence position coordinates when they occur, and one of the plate cylinder and the blanket cylinder of the printing means or both cylinder surfaces are movably provided so as to face each other, and the defect occurrence position coordinates And a control means for controlling the foreign matter removing means for moving the foreign matter from the body surface to remove the foreign matter from the body surface.

According to a second aspect of the present invention, in the printing system according to the first aspect, when a defect is detected by the pattern comparison means, a print product for which the defect is detected is discharged, and a defective product is discharged. The means is provided on the rear side of the pattern comparing means.

The invention according to claim 3 is the invention according to claim 1 or 2.
In the printing system described above, the foreign matter removing means includes a guide rail extending parallel to the body surface, a removing device movably provided along the guide rail, and the removing device on the guide rail. And a drive device that moves along the drive device, and the removing device includes a sheet-like cleaning cloth that is fed from one feeding side roller toward the other winding side roller, the feeding side roller and the winding side roller. And a pressing mechanism for pressing the cleaning cloth against the body surface.

[0011]

According to the first aspect of the present invention, there is provided a pattern comparing means for comparing a pattern to be printed with a pattern printed by the printing means, and calculating defect generation position coordinates when a defect of these patterns occurs. A foreign matter removing unit that moves to the defect occurrence position coordinates and removes foreign matter from the body surfaces of the plate cylinder and the blanket cylinder, and a control unit that controls the foreign matter removing unit. Thus, the pattern printed on the material to be printed by the printing unit is compared with the pattern to be printed by the pattern comparison unit, and when the occurrence of a defect is detected, the foreign matter removing unit is moved to the defect occurrence position to remove the foreign matter on the body surface. Can be removed. Therefore, each process of printing, inspection, and foreign matter removal can be automated.

According to the second aspect of the present invention, when the pattern comparing means detects the occurrence of a defect, the defective article discharging means for discharging the printed material for which the occurrence of the defect is detected is provided. Thus, when the pattern comparison unit detects the occurrence of a defect, the printed material having the defect can be automatically discharged as a defective product. Therefore, it is possible to automate the process of separating good products from defective products.

According to another aspect of the present invention, the foreign matter removing means includes a removing device which is movably provided along a guide rail parallel to the body surface of the plate cylinder or the blanket cylinder, and a drive device which moves the removing means. In this configuration, the removing device is provided with a cleaning cloth that is delivered from one delivery side roller toward the other winding side roller, and a pressing mechanism that presses the cleaning cloth against the body surface. Thus, when the occurrence of a defect is detected by the pattern comparison means, the removing device is moved by the drive device along the guide rail to the defect occurrence position on the body surface, and the cleaning cloth is pressed against the body surface by the pressing mechanism. Foreign substances on the body surface can be automatically removed.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to an embodiment shown in the drawings. Here, for example, an example in which the plate cylinder is provided with a foreign matter removing unit for removing the foreign matter will be described. FIG. 1 shows a schematic configuration of an example of a printing system according to the present invention. As shown in this figure, a printing system 1 includes a paper feed unit 3 that continuously feeds a web (printing material) 2 such as paper wound in a roll in one direction.
A printing unit (printing means) 4 for printing a predetermined pattern on the web 2, an inspection unit 5 for inspecting the printed pattern, a cutting machine 6 for cutting the printed and inspected web 2, and a defective print. Rejecting device for discharging (defective product discharging means) 7
And a folding machine 8 for bending the cut web 2.

The printing unit 4 includes printing mechanisms 10a and 10a for offset printing of black, indigo, crimson and yellow, respectively.
It is composed of b, 10c and 10d. These printing mechanisms 10a, 10b, 10c, 10d are known offset printing mechanisms, and a cylindrical plate cylinder and a blanket cylinder (not shown) are arranged around an axis orthogonal to the feeding direction of the web 2 to be printed. It is rotatably provided. Then, while the plate cylinder and the blanket cylinder rotate in directions opposite to each other, ink is supplied from the plate surface (cylinder surface) of the plate cylinder so that a predetermined pattern is formed on the cylinder surface of the blanket cylinder, and the web is ejected from the blanket cylinder. By transferring ink to the second printing surface, a predetermined pattern is printed.

As shown in FIG. 2A, the printing mechanism 10
a, 10b, 10c, 10d, one or both of the plate cylinder and the blanket cylinder, for example, the plate cylinder 11
Is provided with a foreign matter removing mechanism (foreign matter removing means) 12 for removing foreign matter such as Hicky attached to the plate surface 11a.

In each foreign matter removing mechanism 12, a dust removing unit (removing device) 13 faces the plate surface 11a of the plate cylinder 11,
And the guide rail 1 provided in parallel with the axis of the plate cylinder 11.
4 is configured to be movable along the line 4.
As shown in FIG. 2B, the dust removing unit 13 includes
An unwinding (unwinding side roller) roller 16 that unwinds an unused nonwoven fabric (cleaning cloth) 15 and a winding roller (winding side roller) 17 that is driven to rotate by a motor (not shown) and winds up the unused nonwoven fabric 15 are vertically arranged. Is equipped with. And, between the feeding roller 16 and the winding roller 17,
Guide rollers 18a and 18b are provided at positions facing the plate surface 11a of the plate cylinder 11. Between the guide rollers 18a and 18b, a pusher (pressing mechanism) 1 which is reciprocally driven with a constant stroke by a cylinder 19a or the like.
9 are provided. The guide roller 18a located on the delivery roller 16 side is provided with a spray nozzle (not shown) that sprays the cleaning liquid onto the nonwoven fabric 15.

In such a dust removing unit 13, when the winding roller 17 is rotationally driven, the nonwoven fabric 15 is fed from the feeding roller 16 and the guide roller 18 is fed.
a, 18b through the position facing the printing plate 11a,
It is adapted to be wound up by the winding roller 17. At this time, a fixed amount of cleaning liquid is sprayed onto the nonwoven fabric 15 by a spray nozzle (not shown) provided on the guide roller 18a. Then, when the pusher 19 is operated, the non-woven fabric 15 sprayed with the cleaning liquid between the guide rollers 18a and 18b rotates the plate surface 1 of the plate cylinder 11.
The plate surface 11a is wiped off by being pressed against 1a.

Further, as shown in FIG. 2A, a ball screw 20a is provided in parallel with the guide rail 14, and the main body 13a of the dust removing unit 13 is engaged with the ball screw 20a. There is. And
A drive motor 20b for rotationally driving the ball screw 20a is provided on one end side of the ball screw 20a via a bevel gear 20c. These ball screw 20a, drive motor 2
A drive device 20 for moving the dust removing unit 13 is configured from 0b and the bevel gear 20c. In this drive device 20, the ball screw 20a is connected to the drive motor 20.
The dust removing unit 1
3 can be moved along the guide rail 14.

As a result, in the foreign matter removing mechanism 12, the dust removing unit 13 is driven by the drive unit 20 to the plate surface 11 of the plate cylinder 11.
Move it to any position along a and use the non-woven fabric 15 to print 1
The foreign matter can be removed by wiping off 1a.

As shown in FIG. 1, the inspection section 5 includes a camera 21 for picking up an image of the printing surface of the web 2 printed by the printing unit 4, and a pattern inspecting machine (pattern) for inspecting the image captured by the camera 21. (Comparison means) 22 and a controller 23 for operating the foreign matter removing mechanism 12 and the reject device 7 based on the inspection result of the pattern inspection machine 22.

The inspection unit 5 is controlled as follows. As shown in FIG. 3, the pattern inspection machine 22
In advance, the data of the design to be printed (hereinafter referred to as "reference image") is input and stored (ST
EP1).

When the image captured by the camera 21 (see FIG. 1), that is, the pattern printed on the web 2 by the printing unit 4 (see FIG. 1) (hereinafter, referred to as "inspection image") is input. Image processing the inspection image and comparing it with the reference image (STEP 2). At this time, if the print failure does not occur, the reference image and the inspection image match.
Further, when a foreign matter such as a Hicky adheres to the plate surface 11a of the plate cylinder 11 and a printing defect such as a tear occurs due to this, the reference image and the inspection image do not match.

As a result of comparing the reference image and the inspection image in this way, if they do not match, it is determined that a printing defect has occurred, and pixels at locations where the images do not match (hereinafter referred to as " Bits of "defective pixel" are set, and the position coordinates (XY coordinates) of the bits in the image are set.
Is calculated (STEP 3).

Subsequently, the position coordinates are converted into actual dimensions, that is, the actual position coordinates (XY coordinates) on the plate surface 11a of the plate cylinder 11, of which the coordinates in the axial direction of the plate cylinder 11 (X coordinate). ) Only as defect coordinates (STEP
4).

Then, the defect coordinates are transferred to the control device 23. When the defect coordinates are input, the control device 23 first determines the operating time of each drive motor 20b shown in FIG. 2A based on the defect coordinates. Then, the drive motor 20b is operated at a predetermined speed during the operation time. Then, along with this, the ball screw 20a is rotationally driven, and the dust removing unit 13 of each foreign matter removing mechanism 12 moves to the defect coordinates along the guide rail 14 (STEP 5). Then, the cylinder 19a is operated to press the non-woven fabric 15 against the plate surface 11a of the plate cylinder 11 rotating with the pusher 19 (STEP 6). Then, the plate surface 11a at the defective coordinate position of the plate cylinder 11 is wiped off in the circumferential direction, which causes the plate surface 11a that has caused a defect.
The foreign matter above will be removed.

After a certain period of time, the pusher 19
Is returned to the original position and the pressing of the nonwoven fabric 15 against the plate surface 11a is stopped. Then, the drive motor 20b is operated to return the dust removing unit 13 to the original position (STEP 7). At this time, at the same time that the dust removing unit 13 returns to the original position, the take-up roller 17 is rotationally driven for a certain period of time to wind up the non-woven fabric 15 by a certain size, and the unused portion is newly fed.

In this way, in the inspection section 5, the pattern inspecting machine 22 inspects the printing surface of the web 2, and if a printing defect is found, the foreign matter removing mechanism 12 removes the foreign matter. .

Next, a control method of the entire printing system 1 having the above-mentioned configuration will be described. In the printing system 1, as in the conventional offset printing machine, the printing unit 4 prints a predetermined pattern on the web 2 continuously fed from the paper feeding unit 3. After the printing is completed, the printing surface of the web 2 sent out from the printing unit 4 is picked up by the camera 21 of the inspection unit 5, cut by the cutting machine 6 into predetermined lengths, and then folded by the folding machine 8. It can be bent into a predetermined shape.

Here, the image of the printing surface of the web 2 taken by the camera 21 is inspected by the pattern inspecting machine 22 as described above (STEP 11). When the pattern inspection machine 22 detects a print defect, the control device 23 controls the reject device 7 at a certain time, that is, when a time until the defective print 24 in which the defect is detected reaches the reject device 7. Defective printing 24 that is operated and has a printing defect
Is discharged (STEP 12). At the same time, the inspection by the pattern inspection machine 22 is temporarily stopped and the foreign matter removing mechanism 12 is operated as described above (STEP
13).

Since the printing unit 4 continues to operate even while the foreign matter removing mechanism 12 is in operation, the rejecting device 7 does not operate until the foreign matter removing process of the foreign matter removing mechanism 12 is completed. The defective print 24 is continuously discharged. Then, after the foreign matter removing step is completed, the operation of the rejecting device 7 is stopped at a certain time, that is, at the time when all the defective prints 24 reach the rejecting device 7 (STEP 14). In this way, the reject device 7 is configured to select and eject only the defective print 24 based on the inspection result of the pattern inspection machine 22.

Subsequently, the inspection by the pattern inspecting machine 22 is restarted, and the above control cycle is repeated, and the web 2 thereafter.
Are being inspected (STEP 15).

In the printing system 1 described above, a pattern inspecting device 22 for comparing and inspecting the pattern to be printed with the pattern printed by the printing unit 4 is provided at the subsequent stage of the printing unit 4.
The plate cylinder 11 is based on the defect coordinates calculated by the pattern inspection machine 22.
Foreign matter removing mechanism 12 for removing foreign matter from the plate surface 11a of
And a control device 23 that controls the operations of the foreign matter removing mechanism 12 and the rejection device 7, and the reject device 7 that ejects the defective print 24. This allows
When the pattern inspector 22 detects the occurrence of a print defect,
The controller 23 operates the foreign matter removing mechanism 12 and the rejecting device 7, and the foreign matter removing mechanism 12 causes the plate surface 1 of the plate cylinder 11 to move.
The reject device 7 removes foreign matter from above 1a.
Thus, it is possible to accurately and surely separate defective products from non-defective products and eject only the defective print 24. In this way, the printing system 1 can fully automate each process of printing, inspection, foreign matter removal, and classification of non-defective products and defective products, so that the work efficiency is greatly improved, the burden on workers is reduced, It is possible to obtain effects such as reduction and reduction of defective cost.

The foreign matter removing mechanism 12 comprises a dust removing unit 13 movably provided along a guide rail 14 parallel to the plate surface 11a of the plate cylinder 11, and a drive unit 20 for moving the dust removing unit 13. Garbage removal unit 13
However, the nonwoven fabric 15 is fed from the feeding roller 16 toward the winding roller 17, and the pusher 19 for pressing the nonwoven fabric 15 against the plate surface 11a is provided. As a result, when the pattern inspection machine 22 detects that printing failure has occurred, the dust removing unit 13 is moved to the defect occurrence position and the non-woven fabric 15 is pressed against the plate surface 11a by the pusher 19 to automatically remove foreign matter on the plate surface 11a. Can be removed. In this way, by automating the foreign substance removal work, the work time required for this can be shortened, and the number of defective prints 24 that occur until the work is completed can be reduced. As a result, the defective cost can be reduced. be able to. Moreover, since the foreign matter removing work can be performed without the operator touching the rotating plate cylinder 11, the safety of the work can be improved. In addition, the winding roller 17
Since the non-woven fabric 15 is wound up and the unused portion is always used, it is possible to prevent re-adhesion of foreign matter to the plate cylinder 11 and suppress the occurrence of printing defects. Further, since the dust removing unit 13 is configured to move along the guide rail 14 provided in parallel with the axis of the plate cylinder 11, its control can be easily performed only by a one-dimensional numerical value, that is, the moving amount. It can be carried out.

In the above embodiment, the pattern inspection machine 2
Needless to say, in step 2, when the defective printing is detected at a plurality of locations at the same time, the control device 23 continuously moves the dust removing unit 13 to a plurality of positions to remove foreign matter.

As for the structure of the foreign matter removing mechanism 12 itself, if the foreign matter on the plate surface 11a can be removed by being movable along the plate surface 11a of the plate cylinder 11, the following other configurations are applied. May be. Further, although the foreign matter removing mechanism 12 is provided in the plate cylinder 11, it may be provided in a blanket cylinder (not shown), or both the plate cylinder 11 and the blanket cylinder (not shown). The configuration may be provided for.

Further, in the above-mentioned printing system 1, the printing unit 4 is configured to print only one side of the web 2. However, in the case of printing both sides of the web 2, the inspection unit 5 having the above configuration is used. It may be installed on both sides of the web 2. Further, although the camera 21 is installed on the rear side of the printing unit 4, the camera 21 is installed on the rear side of the printing mechanisms 10a, 10b, 10c, 10d for the respective colors to remove foreign matter for each color. The mechanism 12 may be controlled and operated. Further, the pattern inspection machine 22 may be provided with a color separation function for performing color separation on a captured image, and the foreign matter removing mechanism 12 may be operated only for the colors in which printing defects occur. The printing system having the above-described configuration can be applied not only to the web 2 but also to a case where a sheet-shaped printing material having a certain size is continuously fed and printed, and the printing system is the same as the above. It is possible to produce an effect.

[0038]

As described above, according to the printing system of the first aspect, the pattern to be printed and the pattern printed by the printing means are compared and inspected to calculate the defect occurrence position coordinates. A configuration including: a comparison unit, a foreign substance removal unit that removes foreign substances from the surface of one or both of the plate cylinder and the blanket cylinder based on the defect occurrence position coordinates, and a control unit that controls the foreign matter removal unit. Has become. Accordingly, the pattern printed on the printing material by the printing unit is inspected by the pattern comparison unit, and when the occurrence of a defect is detected, the foreign substance removing unit can be operated by the control unit to remove the foreign substance. In this way, by automating each process of printing, inspection, and foreign matter removal, it is possible to achieve full automation of the printing system, greatly improving work efficiency, reducing the burden on workers, and reducing the number of personnel. it can.

According to the printing system of the second aspect, when the pattern comparing means detects the occurrence of a defect, the defective article discharging means is arranged to discharge the printed material for which the occurrence of the defect is detected. Thus, when the pattern comparison unit detects the occurrence of a defect, the printed material having the defect can be automatically discharged as a defective product. Therefore, it is possible to automate the process of classifying the non-defective product and the defective product, so that the effect according to claim 1 can be made more remarkable, and the defective cost can be reduced.

According to the printing system of the third aspect, the foreign matter removing means is composed of a removing device movably provided along the guide rail and a driving device for moving the removing device.
The removing device is provided with a cleaning cloth that is fed from the feeding-side roller toward the winding-side roller, and a pressing mechanism that presses the cleaning cloth against one or both of the plate cylinder and the blanket cylinder. Thus, when the pattern comparison means detects the occurrence of a defect, the driving device moves the removing device along the guide rail to the defect generation position on the body surface, and the pressing mechanism presses the cleaning cloth against the body surface. Foreign matter on the surface can be automatically removed. In this way, the time taken to remove foreign matter is shortened,
It is possible to reduce the number of defective products generated by the completion of the work, and as a result, it is possible to reduce the defective cost. Moreover, since the foreign matter can be removed without the operator touching the rotating plate cylinder or blanket cylinder at all, the work safety can be improved.

[Brief description of drawings]

FIG. 1 is a diagram illustrating an example of a printing system according to the present invention, which is a schematic configuration diagram of the system.

FIG. 2 is a diagram showing a foreign matter removing unit provided in the printing system, and is a perspective view (a) and a side view (b).

FIG. 3 is a flowchart showing a method of controlling a pattern comparison unit and the foreign matter removal unit provided in the printing system.

FIG. 4 is a flowchart showing a control method of the entire printing system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printing system 2 Web (printing object) 4 Printing unit (printing means) 7 Rejection device (defective product discharging means) 11 Plate cylinder 11a Plate surface (body surface) 12 Foreign matter removing mechanism (foreign matter removing means) 13 Dust removal unit (removing device) ) 14 guide rail 15 non-woven fabric (cleaning cloth) 16 feeding roller (feeding side roller) 17 winding roller (winding side roller) 19 pusher (pressing mechanism) 20 drive device 22 pattern inspection machine (pattern comparison means) 23 control device ( Control means)

Claims (3)

[Claims] 1. A predetermined pattern is offset-printed on a web-shaped or sheet-shaped material to be continuously fed in one direction by a printing means including a cylindrical plate cylinder and a blanket cylinder. A printing system, wherein the printing system is provided on the latter stage side of the printing means, compares the pattern printed on the printing material by the printing means with the predetermined pattern to be printed, and A pattern comparison means for calculating defect occurrence position coordinates when a defect having a different pattern, and one or both of the plate cylinder and the blanket cylinder of the printing means are provided movably opposite to each other.
A printing system comprising: a foreign matter removing unit that moves based on the defect position coordinates to remove foreign matter from the body surface; and a control unit that controls the foreign matter removing unit. 2. The printing system according to claim 1,
When a defect is detected by the pattern comparison unit, a defective product discharging unit that discharges the printed material in which the defect is detected is provided at the rear side of the pattern comparison unit. Printing system. 3. The printing system according to claim 1 or 2, wherein the foreign matter removing means is provided with a guide rail extending parallel to the body surface, and a removing device provided movably along the guide rail. And a drive device that moves the removing device along the guide rail, and the removing device is a sheet-like cleaning cloth that is delivered from one delivery side roller toward the other winding side roller, A printing system comprising: a pressing mechanism that is provided between the feeding-side roller and the winding-side roller and presses the cleaning cloth against the body surface.