JPH03189153A - Multi-color printing device for offset rotary printing machine - Google Patents

Abstract

PURPOSE:To make it possible to print various types of printings including multi-colors in response to editing of various types of printing matters on one surface and both surfaces of a printing paper by a method wherein the title unit is equipped with two sets of blanket cylinders which can come into contact and separate at the time of printing, two sets of planetary blanket cylinders and four sets of plate cylinders. CONSTITUTION:In the case of one web, printing is performed on both surfaces of a printing paper which enters from a passage (m) from the top of a multi-color printing unit 21 with two colors by bringing blanket cylinders 22 and 23 into contact with the paper. For a paper which enters from a passage (a) on the top, one surface is printed with four colors by separating the blanket cylinders 22 and 23 and making the paper run through the blanket cylinder 22, passage (b) and the blanket cylinder 23 and passage (d). Also, in the case of two webs, by making respective webs run from a passage on the bottom (v) (or passage on the top (a)) and (w) (or (d)) through the contact part between the blanket cylinder 22 and a planetary blanket cylinder 25 (24), and the contact part between the blanket cylinder 23 and a planetary blanket cylinder 26 (27) respectively, both surfaces of respective webs can be printed with one color. In this case, the blanket cylinders 22 and 23 are separated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a multicolor printing unit applied to a rotary offset printing press.

[Conventional technology]

FIG. 2 shows a multicolor printing unit of a conventional newspaper offset rotary press.

(1) In Fig. 2, impression cylinders 2 and 3 are removed, and there is a common impression cylinder l shown by a dashed line located in the center, and a common impression cylinder l provided around this common impression cylinder 1 and in contact with this cylinder 1. the blanket cylinders 4, 5.6 and 7 to be obtained and the plate cylinder 8 which can abut each of these blanket cylinders 4.5.6 and 7;
, 9, 10, and 11, there is a common impression cylinder type multicolor printing unit 12.

Four-color printing can be performed on one side of the paper from the path p from above the multicolor printing unit 12, going around the outer peripheral surface of the common impression cylinder 1 and exiting to the path q. Even if the paper gets stale from the path from below, it is possible to print in four colors on one side in the same way. (The path from below is not shown.) (2) In Fig. 2, the common impression cylinder 1 is removed, and the two impression cylinders 2 and 3 and this impression cylinder 2
Blanket cylinders 4 and 5 that can come into contact with each of
and 6, 7, and plate cylinders 8.9.10 and 1 which can abut on these blanket cylinders 4, 5.6 and 7, respectively.
There is a two-impression cylinder type multicolor I11 unit 13 consisting of 1 and 1.

From the path a from above this multicolor printing unit 13, the impression cylinder 2
, printing in four colors on one side of the paper that exits from path clK via path 2, impression cylinder 3, and impression cylinder 3, and printing in two colors on both sides of the paper that exits path e from path a through impression cylinder 2, path C, and impression cylinder 3. It can be done.

However, since the impression cylinder 3 must move forward or backward (or vice versa) with respect to the paper passing through the path or the path C, a forward/reverse device (not shown) is provided for the impression cylinder 3. Since the same thing can happen to the impression cylinder 2 depending on how the paper is passed through, the impression cylinder 2 is also provided with a forward/reverse device.

[Problem to be solved by the invention]

The above-mentioned conventional technology has the following problems.

1) One common impression cylinder type multi-color printing unit can only print four colors on one side at most. Therefore, it is impossible to print a variety of colors in accordance with the editing of printed matter.

2) A single two-impression cylinder multicolor printing unit can print up to four colors on one side and two colors on both sides, so it is possible to print -1 strip of paper (1 web).
When passing through paper, it is possible to perform multicolor printing that satisfies the aforementioned diversity, but when passing through two strips of paper (two webs), each web can only be printed with a maximum of two colors on one side, so the diversity is even greater. Some printing may be required.

3) When performing double-sided two-color printing with a two-impression cylinder type multicolor printing unit,
If the two impression cylinders are not separated by an appropriate distance, when one side of the paper is printed with one impression cylinder and the other side of the paper is printed with the other impression cylinder, the paper will be The pattern printed on one side is transferred to the outer peripheral surface of the other impression cylinder, causing stains on the printed matter. If the interval between these two impression cylinders is made appropriate, the width of the multicolor printing unit will become wider and more installation space will be required.

[Means to solve the problem]

1) In the center of the multicolor printing unit, instead of the two impression cylinders of the conventional two-impression cylinder type multicolor printing unit, two blanket cylinders that can abut and separate from each other are provided.

2) Install two sets of planetary blanket cylinders that can come into contact with each of the blanket cylinders in item 1) above.

3) A total of four plate cylinders are provided that abut each of the four planetary blanket cylinders.

4) A forward/reverse rotation device is attached to each of the blanket cylinders in item 1) above.

[For production]

1) The pattern transferred from the plate cylinder to the planetary blanket cylinder can be retransferred to paper, and the transferred pattern can be retransferred to each of the two contacting and separable blanket cylinders, so that the l web and the two Various types of printing are possible on the web.

2) Since two blanket cylinders are installed that are in contact with each other and can be separated by a small distance, there is no need to install them at a wide interval like in the case of conventional two impression cylinders, so the width of the multicolor printing unit can be reduced. It can be made narrower.

〔Example〕

FIG. 1 shows a multicolor printing unit 21 according to the present invention.

At the center of this unit 21, there are provided blanket cylinders η and 2 that can come into contact with each other (solid line) and separate from each other (dashed line). The planetary blanket cylinders 5 and 26 and τ can contact the blanket cylinders n and O, respectively.
Further, the planetary blanket cylinders 24, 25, 26 and the moss are arranged such that plate cylinders 8°9, 10 and 11 can come into contact with them, respectively. Further, the direction of rotation of the blanket cylinders n and B can be changed along the running direction of the paper by a forward/reverse device (not shown).

Therefore, for one web, the blanket cylinder η
From K (solid line position) where B and B come into contact, two-color printing is performed on both sides of the paper, and the path a from above of this unit is printed.
For twisted paper, print 4 colors on one side by separating the blanket cylinders n and O (dotted line position) and running the paper along path d through the blanket cylinder n, the path and the blanket cylinder O. can do. The same printing is also possible on paper from the lower paths v and w. Furthermore, in addition to printing in up to two colors on one side, which can be done with the two impression cylinders mentioned above,
In the case of a web, the downward (or upward) paths v (a) and W (from (1), the blanket cylinder n
Printing in one color on both sides can be applied to each web by passing the web through the abutment area between the web and the planetary blanket cylinder 25 (incorporated) and the abutment area between the blanket cylinder and the planetary blanket cylinder 26@. At this time, the blanket cylinders n and n are separated.

In addition, when printing in two colors on both sides, the images on each plate cylinder 8 and 9 or 10 and 11 are retransferred to the blanket cylinder n or the sword via the planetary blanket cylinder and 5 or the capital and are printed on paper. ing.

At this time, plate cylinders 8, 9, 10, and 11 are equipped with reverse-printed plates. Furthermore, during the second printing, for example, the pattern of the plate cylinder 8 or 1 is retransferred to the blanket cylinder n or O via the planetary blanket cylinder 1 or n and printed on the paper. At this time as well, back-burned plates are attached to the plate cylinders 8 and 11.

Next, FIG. 3 shows the double-sided four-color printing of one web when two multi-color printing units 21 are stacked on the blanket cylinder n.
The path of the paper when and B are in contact with each other and when they are separated are shown by solid lines and broken lines. In this way, there are various ways to thread the paper even in the same double-sided four-color printing.

Reverse printing refers to when a film is stacked on a plate and baked, and normally printing is done by flipping the film upside down, with the vertical direction of the film stacked on top of the plate (the direction of the bottom of the plate) as the axis. .

〔Effect of the invention〕

The multicolor printing unit of the rotary offset printing press according to the present invention includes two sets of blanket cylinders that can contact and separate from each other during printing, and two sets of planetary blanket cylinders that can contact each of these two sets of blanket cylinders. , and four sets of plate cylinders that can come into contact with each of these four sets of planetary blanket cylinders have the following effects.

1) By printing the pattern retransferred onto the blanket cylinder onto paper, it is possible to print on one or both sides of the paper, including multiple colors, in accordance with the editing of various printed materials for 1 web and 2 web. I can do it.

2) A pair of blanket cylinders that can be brought into contact and separated are installed, so the width of the multicolor printing unit can be narrowed.
It requires less installation space.

3) Since the image on the plate cylinder is retransferred to the blanket cylinder via the planetary blanket and then printed on the printing paper, the image printed on the printing paper is clear and no printing problems such as stains occur.

[Brief explanation of drawings]

Fig. 1 is a side view showing a cylinder device of a multicolor printing unit according to an embodiment of the present invention, Fig. 2 is a side view showing a cylinder device of a conventional multicolor printing unit, and Fig. 3 shows the multicolor printing unit of Fig. 1 in two stages. It is a path diagram of printed paper when stacked. z, 23... Blanket cylinders 24, 25, 26, 27... Planetary blanket cylinders a, b, d, m... 1 web path v, w... 2 web paths

Claims (1)

[Claims] Two sets of blanket cylinders that can come into contact with and separate from each other during printing, two sets of planetary blanket cylinders that can come into contact with each of these two sets of blanket cylinders, and two sets of planetary blanket cylinders that can come into contact with each of these four sets of planetary blanket cylinders. A multicolor printing unit of a rotary offset printing press, characterized in that it is equipped with four sets of plate cylinders.