DE19720746C2 - Printing machine with a printing cylinder - Google Patents

Description

The invention relates to a printing press with a printing cylinder on which the sheet more than one revolution of the impression cylinder lies on the impression cylinder and in a gripper is then printed with several colors one after the other.

It is a printing press with a sheet feeder and feeder sheet stacks and elements for conveying a sheet to be printed to a contact line, feed mechanisms for Sheet conveyance from the contact line to a pressure cylinder with three pressure saddles, this with at least one cylinder group consisting of an offset cylinder with two active surfaces and a printing form cylinder with two active surfaces, together acts, and a delivery containing a delivery chain circle known (US 5 469 787).

To produce a multi-color print, it is two revolutions of the printing cylinder required, a sheet is fed only every second pressure saddle. Furthermore, only one printed sheet is removed from every second pressure saddle.

After the last color has been applied, the printed sheet is transferred to a chain circle ben and placed on a stack of booms.

This printing machine has the disadvantage that due to its construction there are no possibilities are available to ver the sheet in the printed image after the application of the last color noble or to give a larger color effect.

From DE 195 23 378 A1 a printing press is known which, seen from the genus, corresponds to the printing press according to US Pat. No. 5,469,787.

This printing press (DE 195 23 378 A1) also has the disadvantage that it is not possible keit offers to refine the sheet after applying the last color or another color be applied.

DE 39 41 571 A1 contains a sheetfed offset printing press for the execution of the classic offset printing with ink and water. On such machines it is common to do the last or the last and penultimate printing unit for special treatment of the sheet (varnishing, Drying, applying a special color). The arrangement of the cylin which is retained in the printing unit. An existing module (printing unit plus transfer drum) will be converted according to the desired special work.

Based on this prior art, it is an object of the invention to provide a pressure measure Train the type mentioned in such a way that after the application of the last color in the printing unit, further apply the print image by applying varnish or paint can be noble.

According to the invention, this object is achieved by the features of claim 1.

The embodiment according to the invention advantageously enables that on the Printing cylinder printed sheets are treated on the way to the sheet delivery  can. This is done by the application device that is assigned to the second transfer drum is. The second transfer drum takes over in this case by design with a ge closed lateral surface the function of an impression cylinder.

The application device consisting of an application roller, anilox roller and ink fountain can with almost the same structure both for painting and for applying one additional color (e.g. house color) can be used.

For painting, the ink fountain is filled with paint and there is a on the applicator roller Blanket stretched. Should another color be applied to the sheet instead of the varnish conditions, this is filled into the ink fountain instead of the paint and the applicator roller Instead of the rubber blanket, use a flexographic printing plate.

The invention solves on a printing press of the type described, as on the way to Delivery sheet stack optionally additionally coated after the actual printing of the sheets or another color can be applied. This is made possible because it is more advantageous Two transfer drums are provided between the pressure cylinder and delivery chain circuit are.

The invention will be described in more detail below using an exemplary embodiment. The only drawing shows the generic printing machine with the application device.

The printing press is provided with a device for describing 1 of printing plates 3 spanned on a printing form cylinder 2 . The printing form cylinder 2 is equipped with two active surfaces 4 , each of which carries a printing form 3 . The printing form cylinder 2 are also assigned two inking / dampening units 5 which can be switched on and off alternately. The printing form cylinder 2 is operatively connected via an offset cylinder 9 with two surfaces to a printing cylinder 6 .

The printing cylinder 6 has three printing surfaces 7 and accordingly three rows of grippers 8 for gripping sheets 10 to be printed. The printing cylinder 6 is assigned a second formation of offset cylinder 9 , printing plate cylinder 2 , inking / dampening unit 5 and device for loading 1 .

For the promotion of sheets 10 to be printed from a feeder sheet stack 11 to a contact line 13 above the feeder sheet stack 11 elements for promotion 12 are net angeord. A feed mechanism 14 is provided for feeding the sheets 10 to be printed from the contact line 13 to the impression cylinder 6 .

A sheet removal device 26 , which consists of two transfer drums 15 , 16 and the sheet delivery 25, is arranged downstream of the printing cylinder 6 for sheet removal.

The second transfer drum 16 is provided with a closed drum cap, which is of the stable type that the second transfer drum 16 can perform the function of a counter pressure cylinder.

The sheet delivery arm 25 consists of the delivery chain circle 17 guided around the front and rear chain deflection wheel 22 , 23 and of the delivery sheet stack 21 arranged below the delivery chain circle 17 .

The printing press is designed such that the sheet 10 can be completely printed after two rotations of the printing cylinder 6 , that is, two rotations of the printing cylinder 6 are required to produce a four-color print. In this case, only every second gripper row 8 of the printing cylinder 6 is supplied with a sheet 10 and only every second sheet 10 is transferred from the printing cylinder 6 to the sheet discharge device 26 .

The second transfer drum 16 is assigned the application device for coating or applying a 5th color to the sheet 10 . The application device consists of the Farbka most 24 , an anilox roller 27 and an applicator roller 28 , which is provided between the anilox roller 27 and the second transfer drum 16 . The diameter of the transfer drum 16 , applicator roller 28 and anilox roller 27 behaves as 2: 1: 0.5.

During painting, the ink fountain 24 is filled with paint and the applicator roller 28 is covered with a rubber blanket. When printing (applying a 5th color), the ink fountain 24 is filled with ink and the application roller 28 is provided with a flexographic printing plate.

To dry the sheet 10 , a dryer 29 is hen in the front chain deflecting wheel 22 .

The operation of the printing press with the invention is as follows:
The sheet 10 separated from the feeder sheet stack 11 is conveyed by means of the elements for conveying 12 to the contact line 13 of the printing press and transferred from the feed mechanism 14 to one of the gripper rows 8 of the printing cylinder 6 . Only every second gripper row 8 passing the feed mechanism 14 is fed a sheet 10 . The print image is applied by means of the device for writing 1 to the printing plate 3 on the printing form cylinder 2 . The printed image is transferred by the ink / dampening unit 5 inked and to the offset cylinder 9, which passes the print image on the on the cyli the 6 arc 10 lying. The first and second color is carried up on the sheet 10 , then the sheet 10 is lying on the impression cylinder 6 again by a full revolution on the impression cylinder 6 , so that the 3rd and 4th color is applied. Thereafter, the sheet 10 is transferred to the sheet removal device 26 and passed to the second transfer drum 16 lying on the applicator where the sheet painted or 10 is provided with a fifth color in flexographic printing. The sheet 10 is then transferred to the chain circle 17 , dried and placed on the delivery sheet stack 21 .

REFERENCE NUMBERS

1

Description device

2

Plate cylinder

3

printing form

4

active surfaces

5

Inking / dampening unit

6

pressure cylinder

7

print area

8th

rows of grippers

9

offset cylinder

10

arc

11

Investors sheet pile

12

Promotional items

13

Anleglinie

14

feed mechanisms

15

first transfer drum

16

second transfer drum

17

Delivery chain circle

21

Display sheet pile

22

front chain idler

23

rear chain idler

24

paintbox

25

sheet delivery

26

sheet removal

27

anilox roller

28

applicator roll

29

dryer

Claims (3)

1. Printing machine with a printing cylinder ( 6 ) on which the sheet ( 10 ) is more than one rotation of the printing cylinder ( 6 ) and is printed in succession with a plurality of colors in a gripper closure, with the following structure

• - a stack of feeder sheets ( 11 ),
• - Elements for conveying the sheet ( 10 ) from the feeder sheet stack ( 11 ) to the printing cylinder ( 6 ),

the pressure cylinder ( 6 )

• - Has a triple size diameter with three pressure surfaces ( 4 ), and
• - At least one double-size offset cylinder ( 9 ) and double-size printing form cylinder ( 2 ) or double-size printing form cylinder ( 2 ), each with two active surfaces ( 4 ), consisting of an existing cylinder group, in operative connection with the printing cylinder ( 6 ),
• - A device for describing ( 1 ) a printing plate ( 3 ) arranged on the printing form cylinder ( 2 ),
• - A sheet removal device ( 26 ) consisting of
• - A first and a second transfer drum ( 15 , 16 ) and
• - A sheet delivery ( 25 ), wherein
• - The second transfer drum ( 16 ) with a closed drum cap is hen and
• - the second transfer drum (16) is assigned an applicator for applying varnish or paint which (16) betrommel from an ink fountain (24) roller of a grid (27) and a between the screen roller (27) and the second Überga arranged applicator roller ( 28 ).

2. Printing machine according to claim 1, wherein when applying lacquer, the application roller ( 28 ) is provided with a rubber blanket. 3. Printing machine according to claim 1, wherein when applying ink, the application roller ( 28 ) is provided with a flexographic printing plate.