JPH0349880Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Industrial application field] The present invention relates to a registration device for a printing press.

[Conventional technology]

FIG. 2 is a schematic side view of a general sheet-fed printing machine. As shown in the figure, the sheets of paper P formed into sheets and stacked in the paper feed section A are stacked one by one in the printing section B. After the sheets are fed to and printed on, they are sent to a paper discharge section C, where they are stacked on a table. Then, paper P fed from paper feed section A
is the printing unit U of the printing section B as shown in FIG.
One end is caught by the claw 2 of the impression cylinder 1, and is wound around the impression cylinder 1, and as the impression cylinder 1 rotates, the impression cylinder 1
It rotates while being pressed against the blanket 4 of the blanket cylinder 3, which is in contact with the blanket cylinder 3.

On the other hand, the outer circumferential surface of the blanket cylinder 3 is brought into contact with the outer circumferential surface of a plate cylinder 7 to which a printing plate 6 is attached on the outer circumference by a gripping device 5, and the rotation of the plate cylinder 7 causes the blanket of the blanket cylinder 3 to 4 On the surface is the pattern M of printing plate 6.
is transcribed. Therefore, the pattern of the blanket 4 is transferred to the paper P on the outer periphery of the impression cylinder 1, so that the pattern of one desired color is printed.

By installing plural sets (two sets in the illustrated example) of the printing unit U consisting of the impression cylinder 1, blanket cylinder 3 (including the blanket 4), plate cylinder 7, etc. in the printing section B, it is possible to print a plurality of colors. You will be able to print.

In this case, as shown in FIG. 4, a printing plate 6 bearing a pattern M is wrapped around the outer peripheral surface of the plate cylinder 7 by a clamping device 5, and a vertical adjustment bolt 8,
By operating the left and right adjusting bolts 8' and 9', the printing plate 6 is tightly wound around the outer peripheral surface of the plate cylinder 7. Further, the printing plate 6 is arranged for each printing unit U. In this way, the printing plate 6 wound around the outer peripheral surface of the printing cylinder 7 is attached to the printing cylinder 7 by the clamping device 5. In this case, as shown in FIG.
Before starting printing, it is necessary to align the registration marks 10, which have been printed in advance on the printer, to the same position vertically and horizontally for all colors. Therefore, after printing once, look at the printed paper, and if the registration marks 10 of the printing plate 6 of each printing unit are not printed in the same position, find the correction value, and It is required to shift the clamping device 5 along with the printing plate 6 vertically and horizontally by operating the adjustment bolts 9, 9'. This operation is performed every time the pattern M to be printed changes.

In this way, when aligning the registration marks 10 of the printing plates 6 of each printing unit U to the same position, the correction values are found only after printing on paper, and each correction operation for registration mark alignment is required. Since printing has to be performed repeatedly, it takes a lot of effort and time. The operation for this purpose is called register printing, and the printing for registration is called register printing, and it is important to reduce the number of register printing operations in order to improve the efficiency of printing work. For this purpose, the printing plate 6 for each printing unit U needs to be accurately mounted at a predetermined position. FIG. 6 shows a conventional method in which the printing plate 6 is attached to the plate cylinder 7.
The notch 11 provided in the notch 11 is inserted into the corresponding pins 12 and 13 provided in the gripping device 5.
The pin 12 is used to position the printing plate 6 in the horizontal direction, and the pins 12 and 13 are used to position the printing plate 6 in the vertical direction.

FIG. 7 shows another conventional method, in which elongated holes 14 and 17 are formed in the printing plate 6, and corresponding holes 15 and 16 are formed in the gripping device 5. . The plate alignment tool for attaching the printing plate 6 is connected to the elongated holes 14 and 17 of the printing plate 6 and the holes 15 and 16 of the gripping device 5.
Do it by thrusting into it. Hole 16 is for positioning in the left and right direction, and holes 15 and 16 are for positioning in the vertical direction.

[Problem that the invention attempts to solve]

Registration is important in terms of printing quality, and recently it has become necessary for each unit to have a printing plate mounting accuracy of 0.03 mm or less. However, in the conventional example shown in FIG. 6, since the horizontal reference is located at the end, it is difficult to register the other end. The other end may come down by 0.05mm.

In the conventional example shown in FIG. 7, when inserting the plate alignment tool into the elongated holes 14 and 17 formed in the printing plate 6 and the holes 15 and 16 formed in the gripping device 5, the elongated holes 14 and 16 are inserted because the printing plate 6 is soft. , 17 are deformed and disoriented. If the plate alignment tool is operated improperly, it may be misaligned by 0.1mm or more. Furthermore, compared to the conventional example shown in FIG. 6, a plate matching tool is required and extra operations are required.

[Means for solving problems]

The present invention was proposed in view of the above-mentioned conventional problems, and involves processing a U-shaped notch near the center and both ends of the gripping side of the printing plate in the left-right direction. A pin is attached to a position corresponding to the notch, and the pins at both ends have a shape and size to contact the bottom of the notch, and the pin at the center has a diameter that is the same as the spacing between the parallel parts of the notch. The mounting position is shifted in the direction of rotation of the plate cylinder compared to the pins at both ends, and when the pins at both ends contact the bottom of the notch, it is in a position where it contacts the parallel part of the notch, so it is accurate over the entire width. It is an object of the present invention to provide a registration device for a printing press that is in register and eliminates the need for a plate matching tool.

[Effect]

The printing plate is attached by inserting the notch provided in the printing plate into the pin provided in the gripping device. At this time, the pins at both ends contact the bottom of the notch in the printing plate to determine the vertical position, and the central pin contacts the parallel part of the notch to determine the horizontal position.

〔Example〕

FIG. 1 shows an embodiment of the present invention, and is an explanatory diagram showing the relationship between a printing plate and a pin attached to a clamping device of a plate cylinder. In the figure, a U-shaped notch 18 is provided near the center of the printing plate 6 for horizontal positioning, and U-shaped notches 19 are provided near both ends for vertical positioning.

Pins 20 and 21 are attached to the gripping device 5 in correspondence with these notches 18 and 19. In addition, the pins 21 at both ends are not circular, but are made partially thin in order to make it easier to insert the printing plate 6 (to make it easier to attach), and the pin 20 near the center is so that it does not get in the way when determining the vertical position. The pins 21 at both ends are offset from each other in the direction of rotation of the plate cylinder.

[Effect of idea]

In this way, according to the present invention, there are three U points on the printing plate.
A notch in the shape of a letter is provided, a pin is attached to a position corresponding to the notch in the clamping device of the plate cylinder, and the printing plate can be positioned by engaging the notch and the pin.
A plate matching tool is not required for mounting the printing plate, the work of mounting the printing plate is simple, and there is no fear of deformation of the plate due to the plate matching tool. Further, since the reference for registration in the left and right direction is near the center, the accuracy is more than double compared to when it is located at the ends. Furthermore, the mounting position of the pin in the center is shifted in the direction of plate cylinder rotation compared to the pins at both ends, so the diameter of the pin and the left and right positions of the notch can be adjusted at the center, and the bottom position of the notch can be adjusted at both ends. All you have to pay attention to is that it is easier to control accuracy than if the plate is installed at the same position, and this and the above points together make it possible to mount the printing plate easily and accurately.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing one embodiment of the present invention;
The figure is a side view of a general sheet-fed printing press, Figure 3 is a detailed side view of the printing unit, Figure 4 is a perspective view showing the plate cylinder and gripping device, and Figure 5 is a plan view showing a conventional printing plate. ,
FIGS. 6 and 7 are explanatory diagrams showing a conventional registration device. 6... Printing plate, 18, 19... Notch, 20, 21
……pin.

Claims (1)

[Scope of utility model registration request] A U-shaped notch is formed near the center and both ends of the gripping side of the printing plate, and pins are attached to the gripping device of the plate cylinder at positions corresponding to the notches, and the pins at both ends are attached to the notches. The pin in the center has a shape and size that makes contact with the bottom of the notch, and the diameter of the pin in the center is the same as the distance between the parallel parts of the notch, and the mounting position thereof is shifted in the direction of rotation of the plate cylinder compared to the pins at both ends. A registration device for a printing press, characterized in that when the pins at both ends contact the bottom of the notch, they are in a position where they contact the parallel part of the notch.