JPH0224671B2 - - Google Patents

Description

[Detailed Description of the Invention] This invention checks whether the printing plates attached to the plate cylinder of each printing unit of a multicolor printing press are attached to the correct positions and whether the respective color printing plates are in mutual registration. It is related to the device.

Generally, in offset printing, when attaching a printing plate to the plate cylinder of each printing unit, positioning is achieved by fitting a punch hole provided in the printing plate to a pin protruding from the plate cylinder and using a plate vise. The printing plate is attached by fixing one end (the grip), wrapping the printing plate around the plate cylinder in this state, and finally fixing the opposite end of the printing plate (the end of the grip). .

In this case, if the punch holes provided in the printing plate are always formed at a constant position relative to the image, in principle, the relative position of the printing plate of each printing unit can be determined by positioning using the punch holes and pins. However, in reality, it is difficult to always place punch holes in the same position relative to the pattern, and there are also problems with the accuracy of the printing position of the pattern on the printing plate, and the mounting position of the vise on the plate cylinder. Due to various factors such as accuracy and the tightness of the printing plates in a vise on the plate cylinder, the printing plates often do not register with each other when positioned using punch holes and pins.

Therefore, with current multicolor printing machines, adjustment printing is always performed to align the registration when the printing plate is installed, and while checking the registration of the printed matter, any misregistration in the left/right and vertical directions can be corrected using a remote control. In addition, it is essential to correct misregistration that has become distorted by remote control or by stopping the printing press and adjusting the plate vise, and then printing and checking the corrected results on printed matter. .

In this way, with conventional multi-color printing machines, the registration of each printing plate is checked on the printed matter, so it takes a lot of time to adjust the registration, and also requires a lot of paper for adjustment. There are problems such as.

Recently, as a way to solve such problems, as disclosed in Japanese Patent Application Laid-open No. 126537/1983, an automatic drawing machine has been used to print register marks for printing patterns on printing plates and markings for marking the printing plates on each other. After forming registration marks for registration with a scriber needle and forming a pattern on the printing plate based on the registration mark, this printing plate is attached to each plate cylinder in the same manner as before, and the printing machine is started in this state. The operation detects the position of the marking mark formed on each printing plate from a preset reference point, calculates the amount of vertical and horizontal deviation of the detected value from the reference value, and calculates the deviation amount. A device has been proposed that automatically drives the plate cylinders independently to align the register of each printing plate.

Although the above-mentioned problems can be solved by such a device, the configuration involves a major change in the drive system of the printing press itself, making it quite complicated. It is not possible to modify and incorporate the device, so if the user wants the effects provided by the device, he will have to purchase a new printing press with the device, which is very expensive. .

This invention was made in view of the prior art as described above, and its purpose is to eliminate the need to actually print on printing paper in order to align the printing plates of each printing unit with each other. figure,
To provide a printing plate mounting position confirmation device which can easily and quickly confirm the mounting position of a printing plate, has a simple device configuration, and can be easily applied to an existing printing machine.

To summarize the present invention, which has been made to achieve the above object, printing plates of each color having registration marks formed in the margins on both side edges for mounting position alignment are attached to the plate cylinders of a plurality of printing units, and the plate cylinders are rotated. The apparatus is a device for confirming the mounting position of each printing plate based on the register mark while moving the printing plate, and includes an imaging device provided in each printing unit for reading the register mark of the printing plate attached to the plate cylinder; timing control means for determining the timing for capturing an image signal when the imaging device shoots the registration mark; and any one image signal from among the image signals from the printing units other than the one printing unit to be used as a reference. a switching circuit that outputs
storage means for storing the image signal from the reference printing unit and the image signal output from the switching circuit; a mixing circuit for combining the two image signals from the storage means; and displaying the combined image signal from the mixing circuit. The device is equipped with a display device.

The present invention will be described in detail below based on embodiments shown in the drawings.

FIG. 1 is an explanatory diagram of a sheet-fed four-color printing press, which is the most common offset multicolor printing press, and is equipped with the device according to the present invention, and FIG. 2 is an explanatory diagram of the confirmation device according to the present invention. , Fig. 3 is a block diagram of the processing circuit, Fig. 4 is an explanatory diagram of the register mark automatic drawing device, and Fig. 5 is a block diagram of the processing circuit.
The figure is an explanatory diagram of a printing plate on which register marks are formed, and FIG. 6 is an explanatory diagram showing the state of register marks displayed on a CRT.

In FIG. 1, reference numeral 1 indicates a sheet-fed four-color printing machine, and a feeder section 2 is loaded with many sheets of printing paper 9, and this printing paper 9 is collected one sheet by a known structure such as vacuum suction. Destination feeder board 3
The printing paper is fed upward, and the position of the printing paper is regulated on the feeder board 3, and the feeding timing is adjusted, and the printing paper is fed into a printing section consisting of four printing units of each color arranged in series.

In the printing department, each printing unit 10, 20, 30,
40, printing of each color of cyan, magenta, yellow, and black is performed on each plate cylinder 11, 21, 31,
41 to each blanket cylinder 13, 23, 33, 4
The ink transferred to 3 is transferred to each impression cylinder 12, 22, 3.
By being retransferred to the printing paper 9 which is wound around the paper sheets 2 and 42 and conveyed, the printing paper 9 is sequentially overprinted.

The printed printing paper 9' discharged from the final printing unit 40 is delivered to the delivery section 4 via the jaw cylinder 8, where it is delivered to a claw rod mounted on a chain 5' which is passed over the guide wheels 5, 5. The sheets are held in the claws and conveyed onto the paper stacking table 6 by the movement of the chain 5', and then released from the claw rod and stacked on the paper stacking table 6 one after another.

Note that 7 in the figure is a transfer cylinder, which is responsible for transferring printing paper between impression cylinders.

Further, as shown in FIGS. 1 and 2, each printing unit 10, 20, 30, 40 includes a plate cylinder 1.
Registration marks formed on the margins on both sides of the printing plate P which is wound and fixed on the circumferential surface of 1, 21, 31, 41
Imaging devices 14a and 14b, 24a and 24b, 34a and 34 are placed at positions where M ₁ and M ₂ can be read.
b, 44a and 44b, for example, a TV camera using a CCD image sensor, an image pickup tube, etc. is connected to each plate cylinder 11, 21,
31 and 41 at the same position. This imaging device has 1 registration mark M ₁ and M ₂ formed in the margins on both sides of the printing plate P.
For example, two units, 14a and 14b, are provided in one printing unit.

Furthermore, 51 is a rotary encoder as a pulse generating means for generating pulses according to the operating conditions of the printing press, and is provided to determine the timing of capturing image information photographed by the above-mentioned imaging device. In this embodiment, the rotary encoder 51 is connected to the impression cylinder 12 of the printing unit 10.
However, it is not limited to this position, and may be provided at any other position such as an impression cylinder, plate cylinder, etc., which can generate pulses corresponding to the operating speed of the printing press.

Reference numeral 61 is a reference sensor that emits a signal that serves as a reference timing for capturing image information from an imaging device.
It detects rotation and emits one pulse signal each time. Therefore, in this embodiment the reference sensor 61 is connected to the printing unit 1 as shown in FIG.
It is attached to an impression cylinder 12 having the same circumferential length as the plate cylinder of No. A light emitting/receiving element 63 is provided to detect the reference hole 64, and after the light emitting/receiving element 63 detects the reference hole 64 and emits one pulse, the pressure cylinder rotates once and the pulse is emitted again. The reference hole 64 reaches the installation position of the light emitting/receiving element 63 and a pulse is generated.
It is capable of detecting rotation.

Note that this reference sensor 61 has its mounting position,
The configuration is not limited to the above embodiment, and any structure that can generate a signal capable of detecting one rotation or several rotations of the plate cylinder may be used.

As shown in FIG.
0, 20, 30, 40 imaging devices 14a and 14
b, 24a, 24b, 34a, 34b, 44a,
Image signal from 44b, rotary encoder 5
The pulse signal from 1 and the one rotation detection signal from the reference sensor 61 are each input to the processing circuit 100, and the processing circuit 100 processes these input signals to display the CRTs 15, 25, and 25 as display devices.
Images based on image signals as shown in FIG. 6 are displayed at 35 and 45. That is, each CRT is
Registration mark on the printing plate of a printing unit whose screen is divided into two (printing unit 10 here)
M ₁ , M ₂ are permanently displayed as reference marks m ₁ ′, m ₂ ′, register marks M ₁ , M ₂ of the printing plates attached to the remaining printing units (here printing units 20, 30, 40). are sequentially superimposed on the reference marks m ₁ ′ and m ₂ ′ as adjustment marks m ₁ and m ₂ (synthesis).
This is used to check the registration of the printing plate.

In this invention, each printing plate is registered based on the registration marks M ₁ and M ₂ formed on the printing plate, as described later, by overlapping the registration marks M ₁ and M ₂ on the CRT screen. However, it is considered
For this purpose, as shown in FIG. 5, the relative positions of the register mark M ₃ for pattern printing and the registration marks M ₁ and M ₂ for registration on each printing plate must be constant.

In order to accurately write registration marks and registration marks on the surface of the printing plate, for example,
The register mark automatic drawing device shown in the figure may be used. This register mark automatic drawing device 200 has a drawing table 207 on which a printing plate P is placed, and an X-axis rail 205 is provided in front and behind the drawing table 207.
4 is spanned over the Y-axis rail 204, and the head 2 is
03 is attached, and the Y-axis rail 204 is moved in the X-axis direction by an unillustrated X-axis drive motor, and the head 203 is moved in the Y-axis direction by an unillustrated Y-axis drive motor, so that the head 203 can freely move on the plane of the drawing table 207. It is becoming. 206 is a punch block, which punches and holds holes in the portion corresponding to the grip of the printing plate placed on the drawing table, and the printing plate P is fixed on the drawing table with this. . Further, the head 203 is equipped with, for example, a scribing device, in which a registration mark M ₁ for printing a desired pattern according to a command from the arithmetic control unit 202 and a registration mark M placed at a predetermined position with respect to the registration mark M ₁ are provided. ₂ , _M3 can be formed automatically.

If the registration mark M ₃ and register marks M ₁ , M ₂ are formed using this register mark automatic drawing device 200, each mark M 1 , M ₂ will be printed on all printing plates.
The mutual positions between M ₂ and M ₃ can be kept constant.

Next, the processing circuit 100 will be explained based on FIG.

Imaging device 1 provided in printing unit 10
The output signals of 4a and 14b are sent to the A/D conversion circuit 101.
a and 101b, and further converted into digital signals by compression circuits 102a and 102b.
The signal from the D conversion circuit 101a is transmitted to a CRT (described later).
The signal from the A/D conversion circuit 101b is compressed so that it exists only in the area corresponding to the right half of the screen.

The image signals from the two compression circuits 102a and 102b are combined in an OR circuit 103, and the combined image signal is then input to one terminal of an exclusive OR circuit 104. The exclusive OR circuit 104 is responsible for inverting positive and negative images, and the switch 105 connected to the other terminal
When it is open, a negative image signal is output in response to the input image signal, and when it is closed, a positive image signal is output. 106 is a gate circuit, and the imaging device 14
The image signals from a and 14b are outputted only for one vertical blanking period at a predetermined timing as will be described later.

The timing at which the gate circuit 106 opens is determined by the following configuration. That is, the pulse signal emitted from the rotary encoder 51 is counted by a counter 107, and since this count corresponds to the rotation angle of the plate cylinder, it is adjusted to a predetermined angle by the image signal capture timing setting switch 109. A value is set, and the comparator 108 compares the count from the counter 107 with the value of the image signal capture timing setting switch 109. When the two match, the comparator 108 outputs a signal for capturing one pulse image signal. is output. Note that the counter 107 uses the signal from the reference sensor 61 as a clear signal, and therefore the counter 107 is cleared by one rotation of the plate cylinder.

If the pulse signal from the comparator 108 is directly input to the 1 vertical blanking signal (IVB) generation circuit 113, the output signal from the IVB generation circuit 113 becomes the gate signal responsible for opening and closing the gate 106. An image signal is output from the gate 106 each time the rotation is made, and the contents of the storage device 153 are rewritten each time, and the display on the CRT is also changed each time. In this invention, the output signal from the comparator 108 is not input directly to the IVB generation circuit 113, but the plate cylinder is a counter 110 to open the gate 106 once every several rotations of
A comparator 111 and a sampling interval switch 112 are interposed.

That is, a desired number of sampling intervals is set by the sampling interval switch 112, and the set number is compared with the number counted by the counter 110 (equal to the number of rotations of the plate cylinder) by the comparator 111. When they match, the comparator 111 A pulse signal is output from the IVB generation circuit 1 by inputting this pulse signal to the IVB generation circuit 113.
From 13, gate 1 only for 1 vertical blanking period.
A command to open 06 is given to gate 106, and an image signal is output.

The image signal output from the gate 106 receives the clock from the clock generation circuit 152 from the counter 1.
The data are sequentially stored in the address of the storage device 153 specified by counting in 51.

Although omitted in Fig. 3, the number 10
Circuits completely similar to the circuits existing in the block indicated by 0C are arranged in the blocks indicated by numbers 100M, 100Y, and 100BK corresponding to each printing unit 20, 30, and 40, and
a and 24b, 34a and 34b, 44a and 44b are connected to 101a and 101b to A/D conversion circuits of 100M, 100Y, and 100BK, respectively,
Also, the output of the counter 107 is 100M and 10M, respectively.
It is connected to the comparator 108 of 0Y and 100BK.

Here, 100C, 100M, 100Y, 10
The values of each image signal capture timing setting switch 109 present in 0BK are determined as follows.

That is, each printing unit 10, 20, 30, 40
In the image pickup device, the plate cylinders 11, 21, 31, 41
It is installed in a certain positional relationship with respect to the
In addition, in a normal printing press, the phases of the printing plates attached to each plate cylinder are different, so the timing of capturing the image signal from the imaging device, that is, the timing of opening each gate 106, is adjusted to the phase difference unique to the printing machine. It is necessary to make them different.

On the other hand, as a matter of course, it is necessary to capture image information during the period when the register mark is in the field of view of the imaging device. The number of pulses counted from the rotary encoder 51 at a certain moment while the registration mark of the plate is in the field of view of the imaging device is set as the number set in the image signal capture timing setting switch 109 of the printing unit 10, and the number of pulses counted from the rotary encoder 51 at a certain moment while the registration mark of the plate is in the field of view of the imaging device is set as the number set in the image signal capture timing setting switch 109 of the printing unit 10. , 30, 40, printing unit 10
The timing for capturing the image signal is determined by adding or subtracting the number of pulses corresponding to each phase difference from the number set in the timing setting switch 109 of the printing unit 10.

This synchronizes the capture of image signals from the imaging devices of each printing unit, and if the printing plates are registered with each other, the registration marks on the URT screen (described later) will be completely overlapping. become.

Furthermore, the image signals output from 100M, 100Y, and 100BK are input to a switching circuit 170, and only one of these image signals is selectively output. This switching circuit 170 may be of a type in which an operator manually switches the connection terminal to select the image signal to be output.
This is used to select the image to be displayed on the CRT display device.

The image signal output from the switching circuit 170 is sequentially stored in the storage device 163 by counting the clock generated by the clock generating circuit 162 by the counter 161 and using the counted number as an address signal.

Reference numeral 190 denotes a mixing circuit, to which the storage device 153 and the storage device 163 described above are connected, to which two image signals are input, and further to which a synchronization signal generation circuit 180 is connected, to which a vertical blanking signal and a horizontal blanking signal are input. , the two image signals are combined in this mixing circuit 190, and each CRT display device 1 is combined as shown in FIG.
The screens 5, 25, 35, and 45 are divided left and right, and two register mark images "+" and "-" are displayed. In addition, 191 is a video amplification circuit, which has four units.
Provided for connecting a CRT display device.

As seen in FIG. 6, in this embodiment, the image of the register mark based on the image signal from the printing unit 10 is constantly projected as the reference mark m ₁ ', m ₂ ', and the other printing units 20, 30, The image of the register mark based on the image signal selected by the switching circuit 170 from among the image signals from 40 is displayed as adjustment marks m ₁ and m ₂ . Therefore, since the mounting position of the imaging device is the same in all printing units, and the timing of capturing the image signal is also set taking into account the phase difference between the plate cylinders of each printing unit, the If the register is correct, each register mark m ₁ and m ₂ are all reference marks m ₁ ′,
It will completely overlap m ₂ ′.

The configuration of the present invention is as described above, and the installation position of the printing plates can be confirmed using such a device and the registration of each printing plate can be adjusted in the following manner.

First, as mentioned above, registration marks M3 are formed on printing plates of each color using an automatic register mark drawing device, etc. to regulate the printing position of the image, and at the same time, register marks M ₃ are formed on the printing plates of each color to regulate the printing positions of the printing plates. Register marks M ₁ and M ₂ are formed in the margins on both sides of the printing plate.

After forming a pattern on such a printing plate, each printing unit 10, 2 of the printing press is
Attach and fix to the 0, 30, and 40 plate cylinders.

After this, the printing press is rotated without passing the printing paper through, the registration marks M ₁ and M ₂ of each printing plate are photographed by the imaging device of each printing unit, and the image signal from each imaging device is captured at a predetermined timing. .

The image signal from the printing unit that serves as the reference is always input to the display device and displayed as reference marks m ₁ ′, m ₂ ′ on the screen of the display device (CRT), and the image signals from other printing units are inputted at any time. Only one selected image signal corresponds to the reference mark m ₁ ′,
m ₂ ′ and displayed on the screen of the display device as adjustment marks m ₁ and m ₂ .

As mentioned above, if the printing plates in the two printing units are in mutual registration, the marks m ₁ ', m ₂ ' and m _{1, m 2 based on the two image signals should completely overlap, and the marks m 1} , m ₂ based on the two image signals should completely overlap. By looking at the overlapping state of the two marks, it is possible to confirm the state of registration between the two printing plates.

If the two marks m ₁ ′, m ₂ ′ are misaligned with m ₁ , m ₂ , adjust the plate cylinder or printing plate of the printing unit corresponding to the adjustment marks m ₁ , m ₂ and correct the marks m 1 ′, m 2 ′. ₁ and m ₂ completely overlap marks m ₁ ′ and m ₂ ′. This allows the printing plates in the two printing units to be aligned with each other.

This procedure is sequentially applied to other printing units by switching the image signals to be output using the switching circuit, and by matching the printing plates of the other printing units to the printing plate of the reference printing unit, all the printing plates are You can make a pretty good guess.

If necessary, in order to facilitate comparison on the URT screen, either the reference marks m ₁ ′, m ₂ ′ or the adjustment marks m ₁ , m ₂ may be inverted from positive to negative using an exclusive OR circuit. You can also show it.

In this way, once all the printing plates are in register, regular printing, called actual printing, is then performed through the printing paper.

The above is a description of one embodiment of the present invention, and the present invention is not limited to the above embodiment in any way.

That is, in this embodiment, the CRT display device for register confirmation is provided for each printing unit, since many of the current printing machines are integrated into each printing unit and have a register adjustment button. 3
An example is shown in which 5 and 45 units are installed, but if it is a centralized remote control system, one unit should be installed near the control console.
A CRT is sufficient.

Also, in this embodiment, a compression circuit and an OR circuit are provided to display two register marks on one CRT screen.
Although a configuration is shown in which the images of M ₁ and M ₂ are displayed in a composite manner, it is possible to display the images of the two register marks M ₁ and M ₂ separately.
It may also be configured to be displayed on a CRT. In this case, the compression circuit and OR circuit are not required, but the number of exclusive OR circuits, gates, and CRTs, and the storage capacity of the memory are required to be twice as large as in this embodiment.

Furthermore, the shape of the register mark formed on the printing plate is not limited to the "+" and "-" shapes of this embodiment.
Any mark such as "<" or "" that has a shape that can detect misregistration in the vertical direction, horizontal direction, and twist of the printing plate may be used.

Further, although the printing machine targeted in the above embodiment is a four-color sheet-fed printing machine, the present invention is not limited to this, but can be applied to a wide range of offset multicolor printing machines such as offset rotary printing machines. Can be done.

This invention is as described in detail above, and when aligning printing plates of an offset multicolor printing machine, a reference mark and an adjustment mark are sequentially synthesized and projected on a CRT screen, and these marks are combined and projected on a CRT screen. Depending on how the marks overlap, it is easy to check the registration of the printing plate to be adjusted relative to the standard printing plate, and
If the printing plate is not in the correct register, it can be easily adjusted by remotely controlling the printing plate to be adjusted so that the adjustment mark overlaps the reference mark while looking at this CRT screen.

Therefore, compared to the conventional method, the time required for registering the printing plate is greatly shortened, and printing paper for registering is also no longer necessary.

Furthermore, the confirmation device according to the present invention can be installed in an existing printing press without changing its basic structure, making it possible to effectively utilize the existing printing press, resulting in extremely practical and excellent effects. It is something that plays.

[Brief explanation of drawings]

The drawings show one embodiment of the invention,
FIG. 1 is an explanatory diagram of a four-color offset printing machine equipped with a device according to the present invention;
The figure is an explanatory diagram of the device according to the present invention, and the third
The figure is a block diagram of the processing circuit, Figure 4 is an explanatory diagram of a register mark drawing device, Figure 5 is an explanatory diagram of a printing plate on which register marks are formed, and Figure 6 is an explanatory diagram of a printing plate on which register marks are formed. FIG. 4 is an explanatory diagram showing the state of the registered register mark. 11... plate cylinder, 14a, 14b... imaging device,
15...CRT, 51...Rotary encoder,
61...Reference sensor, 100...Processing circuit, _M1 ,
M ₂ ...Register mark, m ₁ , m ₂ ...Register mark for adjustment displayed on CRT screen, m ₁ ′, m ₂ ′ ...
The standard register mark displayed on the CRT screen, P...
...Print version.

Claims (1)

[Claims] 1 Attach each color printing plate with registration marks formed in the margins on both sides for mounting position alignment to the plate cylinders of multiple printing units, and check the installation position of each printing plate based on the registration marks while rotating the plate cylinders. In a device that performs printing, an imaging device is provided in each printing unit to read the register mark on the printing plate attached to the plate cylinder, and a timing control is provided in each printing unit to capture image signals from the imaging device at a predetermined timing. means, and any one of the image signals from the imaging devices provided in the other printing units, excluding the image signals from the imaging device provided in the one printing unit serving as a reference.
a switching circuit for outputting two image signals; a storage means for storing an image signal from the reference printing unit and an image signal output from the switching circuit; and a mixing circuit for combining the two image signals from the storage means. and a display device that displays a composite image signal from a mixing circuit.