JPH07205391A - Printing mechanism of offset rotary press - Google Patents

Abstract

PURPOSE: To reduce the number of rollers of an inking mechanism and a dampening printing mechanism for a printing mechanism. CONSTITUTION: To omit corresponding rollers of an inking and dampening printing mechanism of the printing mechanism 3 of the offset rotary press, the inking unit 5 or the dampening printing mechanism 4 is arranged on a transfer cylinder 2 without having a roller for transferring or coating with ink or moisture.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a printing mechanism for a so-called offset rotary printing press.

[0002]

[Prior Art and Problems to be Solved by the Invention]
In the inking and dampening printing mechanism of an offset rotary printing press, more or less a large number of rollers are required to carry the ink or wetting agent from the measuring device to the printing plate. For example, DE 33 08 067 C1 discloses a similar inking and dampening printing mechanism. Even in the short inking mechanism, at least one other inking roller is connected between the raster roller and the printing plate cylinder (DE 34 42 661 A1).

The present invention is directed to reducing the number of rollers in an inking mechanism and a dampening printing mechanism in a generic printing mechanism.

[0004]

The present invention solves the above problems by the features described in claims 1 and 5. The present invention utilizes the soft features of the transfer cylinder. Further, if the ink and the wetting agent are directly applied to the transfer cylinder, the inking device and the flexible roller of the dampening printing mechanism can be omitted.

Further effective embodiments will be apparent from the dependent claims and the specification.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a printing mechanism 3 of an offset rotary printing press including a printing plate cylinder 1 and a transfer cylinder 2. The printing plate cylinder 1 is provided with a dampening printing mechanism 4, and the transfer cylinder 2 is provided with an inking device 5.

The printing mechanism 3 shown here is, for example,
It operates based on a rubber-rubber system with a similar printing mechanism not shown and prints on a web (web) 6. Therefore, the printing plate attached to the printing plate cylinder 1 is dampened by the dampening printing mechanism 4, and the non-printing part is wetted with water. The water film (water film) in the non-printed portion is transferred to the transfer plate of the transfer cylinder 2 by, for example, a rubber blanket having or not having usual compressibility. However, in this embodiment, the surface of the transfer plate is particularly hydrophilic. The inking device 5 brought into contact with the transfer cylinder 2 can apply ink to a portion of the transfer cylinder 2 that is not wet with water, that is, an image portion. The image is transferred to the web 6. As an inking device, FIG. 1 shows an anilox inking device in which the raster roller 7 is in contact with the transfer cylinder 2. Although not shown in the drawing, this inking device can be installed above the transfer cylinder 2.

The present invention can also be implemented using an inking device having another structure, as shown in FIG. In the following examples, the member numbers used for FIG. 1 will continue to be used. In Figure 2,
An inking device 8 for newspaper printing is installed in the transfer cylinder 2. Ink material rods or measuring devices, for example inking rollers with wedge-shaped ink fountains, are not shown. Here, two conventional ink application rollers are not normally used, and in the inking device, the rigid roller 9 located on the downstream side contacts the transfer cylinder 2.
This roller 9 is in this case a cylinder whose color does not change. As another embodiment, an inking device 10 including, for example, three rollers is installed above the printing plate cylinder 1. The printing mechanism 11 is the printing mechanism 3 of FIG.
Works the same as.

In the printing mechanism 12 shown in FIG. 3, the printing plate cylinder 1 is provided with an inking device 5, and the transfer cylinder 2 is provided with a dampening printing mechanism 13. The dampening printing mechanism contacts the transfer cylinder 2 at the dampening transfer roller 14 rather than at the dampening roller.

In the case of this printing mechanism 12, the transfer cylinder 2 is dampened by the dampening printing mechanism 13. The transfer cylinder 2 itself further wets the printing plate of the printing plate cylinder 1.
Therefore, the inking device 5 dyes only the portion to be printed. The printed portion coated with these inks applies the ink to the transfer cylinder 2. Then, the transfer cylinder 2 prints the paper roll 6. Printing plate cylinder 1
Since the transfer cylinder 2 and the transfer cylinder 2 usually have the same diameter, the inked portion of the transfer cylinder 2 always coincides with the printed portion of the printing plate at a rotation of 1: 1.

The printing mechanism 15 shown in FIG. 4 is similar to the printing mechanism 3 shown in FIG. However, the dampening printing mechanism 16 in the printing mechanism 15 directly contacts the transfer cylinder 2 with the chrome plating cylinder 17 without using the dampening transfer roller. The printing mechanism 15 is shown in FIG.
The same operation as the printing mechanism 12 shown in FIG.

In another embodiment, the chrome plating cylinder 17 can be omitted. In this case, the wetting agent is applied directly to the transfer cylinder with a conventional spray or centrifugal dampening printing mechanism (wheeler).

In the printing mechanism shown in FIGS. 3 and 4, when the inking device is removed, the dampening printing mechanism can be used as a cleaning device for preventing accumulation of dust on the transfer cylinder 2.

As already mentioned, the inking devices 5, 8 of the printing mechanism according to FIGS. 1 and 2 and the dampening printing mechanisms 13, 16 of the printing mechanism according to FIGS. 3 and 4 rotate the transfer cylinder 2. It can also be installed after the printing area in terms of orientation. The inking device and the measuring device of the dampening printing mechanism have been schematically described because they are not included in the claims. The printing plate and / or the transfer plate can also be formed as an intermittent or continuous sleeve.

[Brief description of drawings]

FIG. 1 is a side view showing a schematic configuration of a printing mechanism according to an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram showing another embodiment of the inking device in the printing mechanism according to the present invention.

FIG. 3 is a side view showing a schematic configuration of a printing mechanism according to another embodiment of the present invention.

FIG. 4 is a side view showing a schematic configuration of a printing mechanism according to another embodiment of the present invention.

[Explanation of symbols]

 1 printing plate cylinder 2 transfer cylinder 5,8,10, inking device 4,13,16 dampening printing mechanism

Claims (7)

[Claims] 1. In a printing mechanism of an offset rotary printing press having at least one printing plate cylinder, a transfer cylinder, an inking mechanism, and a dampening printing mechanism, the inking device (5, 8) uses a normal ink application. A printing mechanism of an offset rotary printing press, which is in contact with a transfer cylinder (2) without a roller. 2. The printing mechanism according to claim 1, wherein the surface of the transfer cylinder (2) is hydrophilic. 3. The printing mechanism according to claim 1, wherein the inking device is an anilox inking device that contacts a transfer cylinder (2) by a raster roller (7). 4. The printing mechanism according to claim 1, wherein the inking device (5, 8) is located in front of the printing plate cylinder (1) with respect to a rotation direction of the transfer cylinder (2). Alternatively, the printing mechanism is selectively installed later. 5. In a printing mechanism of an offset rotary printing machine having at least one printing plate cylinder, a transfer cylinder, an inking mechanism and a dampening printing mechanism, the dampening printing mechanism (13) uses a normal wetting roller. A printing mechanism of an offset rotary printing press, which is in contact with a transfer cylinder (2) without having it. 6. Printing mechanism according to claim 5, characterized in that the dampening printing mechanism (16) contacts the transfer cylinder (2) by means of a chrome plating cylinder (17). 7. A printing mechanism according to claim 5 or 6, wherein the dampening printing mechanism (13, 16) is selective before or after the printing plate cylinder (1) with respect to the direction of rotation of the transfer cylinder (2). A printing mechanism characterized by being installed in.