GB2215274A

GB2215274A - Off-set printing and varnishing machine

Info

Publication number: GB2215274A
Application number: GB8902253A
Authority: GB
Inventors: Arndt Jentzsch; Klaus Schanze
Original assignee: Kombinat Polygraph Werner Lamberz VEB; Polygraph Leipzig Kombinat Veb
Current assignee: Kombinat Polygraph Werner Lamberz VEB; Polygraph Leipzig Kombinat Veb
Priority date: 1988-02-04
Filing date: 1989-02-02
Publication date: 1989-09-20
Anticipated expiration: 2009-02-02
Also published as: DD269356A1; DE3901174C2; IT1232566B; FR2626813B1; JPH01288443A; FR2626813A1; GB2215274B; IT8967065A0; GB8902253D0; JP2838826B2; DE3901174A1

Description

PRINTING MACHINE The present invention relates to a printing machine.

A sheet printing machine is known (DE 3203948) in which rubber cylinders of individual printing units are arranged in series in contact with one another for ink transmission. A cylinder, which also represents a feeder drum and a deflecting system of a discharge chain circle, is pressable against a rubber cylinder. In that case, it is disadvantageous that numerous ink gaps are necessary for printing image transmission, which cause point enlargement, image doubling and thereby loss in quality. Moreover, regulation of the ink layer thickness according to the different lengths of the path of the ink to the sheet or web material to be printed is difficult in this machine by reason of the more than average number of gaps. This design is not usable for modern machines with a large number of printing units, for example a ten-colour machine, due to the mentioned disadvantages. A further disadvantage is that first form and perfecting form printing are not possible with this design.

There is therefore a need for a printing machine which may provide an increase in the quality of printing, a simplification of sheet or web guidance and thereby an increase in printing performance, as well as enhancing the utility of the machine, especially on the image transport principle with complete image transmission.

According to the present invention there is provided a printing machine comprising sheet or web material feed means, sheet or web material discharge means, cylinder means to transfer sheet or web material from the feed means to the discharge means, an endless, printing image collecting element contacting the cylinder means, at 1 - 2 least one printing unit co-operable with the endless element and comprising a printing cylinder, a counter-ores sure cylinder and inking and moistening means, varnishing means co-operable with a countercylinder and arranged upstream of the printing unit or units with respect to a direction of travel of the endless element towards the cylinder means, a first drier arranged upstream of the printing unit or units with respect to said direction, and a second drier arranged downstream of the printing unit or units with resoect to said direction, the endless element extending through a pressure zone between the printing and counter-pres sure cylinders of the or each unit, through a pressure zone between the varnishing means and the countercylinder, and thr-ough drying zones of the driers.

The cylinder system may be constructed as a sheet-guiding central printing cylinder with sheet gripper means, and may further include at least one drum system forming part of a perfecting equipment arranged downstream of the central printing cylinder and containing at least one perfecting cylinder. Alternatively, the cylinder system may be constructed as a web-guiding central printing cylinder, and may further include at least one drum system forming part of a perfecting equipment arranged downstream of the central printing cylinder and containing a second web-guiding perfecting cylinder. The drum system preferably comprises at least one sheet perfecting cylinder with at least one gripper system, or a sheet perfecting cylinder with at least one gripper system and a transfer cylinder with at least one gripper system, or two transfer cylinders selectably constructed as sheetturning cylinders or transport cylinders, or four transfer cylinders constructed selectably as sheetturning cylinders or transport W, - 3 cylinders. The perfecting equipment is preferably constructed as a printing unit comprising a printing plate cylinder with inking and moistening mechanism and an offset cylinder disposed in pressurable contact with the printing plate cylinder and the drum system, or a further printing image collecting element disposed in pressure contact with the drum system and with at least one printing plate cylinder with inking and moistening mechanism and a counterpressure cylinder. At least one printing plate cylinder with inking and moistening mechanism can be arranged above an upper run of the printing image collecting element, or at least one printing plate cylinder with inking and moistening mechanism can be arranged below the lower run of the printing image collecting element. In yet another possible arrangement, at least one printing plate cylinder with inking and moistening mechanism is arranged above the upper run of the printing image collecting element and at least one printing plate cylinder with inking and moistening mechanism is arranged below the lower run of the element. The element can be constructed as an endless offset blanket, or at least one offset blanket piece can be connected with the printing image collecting element, or the printing image collecting element has gripper means for an offset blanket portion. The varnishing mechanism preferably comprises a varnish trough, a coating roller, a varnish scoop roller and a varnish metering roller. The first drier can be constructed as an initial drier and the second drier as an energy drier.

Embodiments of the present invention will now be more particularly described by way of example with reference to the accompanying drawings, in which:

Fi 9. 1 Fi g. 8 Fi g. 3 is a schematic elevation of a first printing machine embodying the invention, with upper run printing units; 2 is a schematic elevation of a second printing machine embodying the invention, with lower run printing units; is a schematic elevation of a third printing machine embodying the invention, with upper and lower run printing units; Fi g. 4 is a schematic elevation of a fourth printing machine embodying the invention, with double-run printing units; Fi g. 5 is a schematic elevation of a fifth printing machine embodying the invention, with single printing units; Fi g. 6 is a schematic elevation of a sixth printing machine embodying the invention, for selectable first form printing and first and perfecting form printing and I with a single printing unit; Fi g. 7 is a schematic elevation of a seventh printing machine embodying the invention, for selectable first form printing and first and perfecting form printing (printing image collecting element); is a schematic elevation of an eighth printing machine embodying the invention, for selectable first form printing and first and perfecting form printing (single printing unit and transfer cylinder); Fig. 9 is a schematic elevation of a ninth printing machine embodying the invention, for selectable first form printing and first and perfecting form printing (sheet transfer system PLANETA); ji 1 - Fig. 11 Fig. 10 is a schematic elevation of a tenth printing machine embodying the invention, for selectable first form printing and first and perfecting form printing (sheet transfer system MILLER): and is a schematic elevation of an eleventh printing machine embodying the invention, for first form printing and first and perfecting form printing.

Referring now to the drawings, there is shown a printing machine which, in a construction for sheet printing, comprises a sheet-guiding system and a printing-image-guiding system. The sheet-guiding system consists (Figs. 1 to 4) of a sheet feed with a feeder 1, a feed table 2 and a sheet transfer 3, for example a preliminary gripper, a sheet transport system constructed as a cylinder system 4 arranged downstream of the sheet transfer, and a sheet discharge constructed as a sheet deposit device 5. The cylinder system 4 includes a sheet-guiding central printing cylinder 4.1. The cylinder 4.1 is provided with two gripper systems 6, wherein the number of the gripper systems can be greater or smaller. In a construction for first form printing and first and perfecting form printing (sheet printing), the cylinder system 4 includes a sheet-guiding central printing cylinder 4.1 and a drum system 27 inserted between the cylinder 4.1 ahd the sheet deposit 5. The drum system 27 is part of perfecting equipment 28. The drum system 27 comprises a sheet perfecting cylinder 29.1 (Fig. 5), a sheet perfecting cylinder 29.1 and a transfer cylinder 30 (Figs. 7 and 8), two cylinders selectably operable as sheet-turning cylinders or transport cylinders (PLANETA system according to DD 54 703, Fig. g), or four cylinders selectably operable as sheet-turning cylinders or 1 transport cylinders (MILLER system according to DE 1 107 246, Fig. 10). In first and perfecting form printing according to the PLANETA system, the first sheet-turning cylinder functions as sheet-turning cylinder 31 and the second sheet-turning cylinder as sheet perfecting cylinder 29.1 5 The sheet turning takes place in known mode and manner either between the central printing cylinder 4.1 and the turning cylinder 31, or between the cylinder 31 and the sheet perfecting cylinder 29.1. No sheet turning takes place in first form printing and the cylinder system 27 consists only of transport cylinders 32. The two sheet-turning 10 cylinders 29.1 and 31 are usable as transport cylinders 32 after resetting of the systems in known mode and manner. In the case of first and perfecting form printing according to the MILLER system, the first, second and third sheet-turning cylinders 31, 33 and 34 function as sheet-turning cylinders and the fourth sheet-turning 15 cylinder as sheet perfecting cylinder 29. 1. The sheet turning takesplace between the second and third sheet- turning cylinders. No sheet turning takes place in first form printing and the cylinder system 27 consists only of transport cylinders 32. The four sheet-turning cylinders are usable as transport cylinders 32 after resetting of the systems. 20 The central printing cylinder 4.1, the perfecting cylinder 29.1, the transfer cylinder 30, the turning cylinders 31, 33 and 34 and the transport cylinders 32 each have two gripper systems 6, wherein the number of the gripper systems can be greater or smaller. In a construction as a roller printing machine, the machine comrises a web-guiding system and a printing-image-guiding system. The web-guiding system (Fig. 5) consists of a web feed with an unreeling - 7 device 22 with a web-guiding roller 23, a cylinder system 4 constructed as a web-guiding central printing cylinder 4.2, and a web discharge constructed as a reeling device 24 with web discharge rollers 25. In the construction for first and perfecting form printing (roller print- ing), the cylinder system 4 includes a web-guiding central printing cylinder 4.2 and aweb-guiding perfecting cylinder 29.2 arranged downstream of the cylinder 4.2.

The printing-image-guiding system comprises a printing image collecting element 7, which is constructed as an endless belt guided over two deflecting rollers 8 and disoosed in contact with the cylinder system 4, i.e. with the printing cylinder 4.1 or 4.2. The printing image-guiding system also comprises at least one printing unit, which consists of a printing cylinder 9, an inking mechanism 10, a moistening mechanism 11 and a counterpressure cylinder 12.

Finally, the printing-image-guiding system comprises a varnishing mechanism 36, which is arranged upstream of the first printing unit and co-operates with a countercylinder 15, with a first drier 37 as well as a second drier 38 arranged downstream of the last printing unit. The varnishing mechanism 36 consists of a varnishing trough 39, a coating roller 40, a varnish-metering roller 41 and a varnish scoop roller 42.

The varnish should be such that it adheres to the element 7 after dry ing by the first drier 37, that the printing ink applied by the print ing units can penetrate slightly without splitting-back and doubling in the following printing unit, and that the varnish layer with the printed image can detach from the element 7 by the effect of the second drier 38 and can then be applied, by the contact between the element 7 and cylinder system 4, to the sheet or the web to be printed on.

The deflecting roller 8 functions, according to Fig. 1, as a countercylinder 15. The first drier 37 is preferably constructed as an initial drier, for example ultra-violet drier. The second drier 38 can be constructed an an energy drier, for example infra-red drier.

The upper run 13 of the printing image collecting element 7 passes through the contact zone between the coating roller 40 of the varnishing mechanism 36 and the countercYlinder 15, the effective zone of the first drier 37, the contact zone between plate cylinder 9 and counterpressure cylinder 12, and the lower run 14 of the element 7 passes through the effective zone of the second drier 38 (Figs. 1 and 4). At least one washing device 16 and a patch collector 17 act on the element 7.

The element 7 is constructed as endless offset blanket 18 (Fig. 3), or at least one offset blanket piece 19 is connected with the element 7, wherein a gap for the gripper system 6 is provided in the case of several offset blanket pieces connected with the element (Fig. 1). The printing image collecting element 7 can also consist of at least one offset blanket portion 21 guided by a front edge or a front edge and rear edge and/or side edge gripper system 20 (Fig-. 2).

In the embodiment illustrated in Fig. 2, the printing units, consisting of printing plate cylinder 9 with inking and moistening mechanisms 10 and 11 and counterpressure cylinder 12, are disposed in contact with the lower run 14 of the element 7.

An embodiment is illustrated in Fig. 3, wherein a first number of printing units is disposed in contact with the upper run of the t M 1 - 9 element 7 and a second number of printing units with the lower run of the element 7.

In the further embodiment illustrated in Fig. 4, a further printing image collecting element71, with corresponding printing units, is associated with the sheet-guiding central printing cylinder 4.1.

An embodiment is illustrated in Fig. 5, wherein a printing image collecting element 7 is associated with the web-guiding central printing cylinder 4.2. Perfecting equipment 28 is associated with the perfecting cylinder 29. The perfecting equipment 28 consists of a single printing unit 28.1 or a further printing image collecting element 28.2. The single printing unit 28.1 consists of an offset cylinder 26 and a printing cylinder 9 with moistening and inking mechanisms 10 and 11. The further element 28.2 is constructed analogously to the element 7 In use, a sheet withdrawn from the feeder 1 is conducted by way of the feed table 2 and the sheet transfer 3 to the central printing cylinder 4. 1. The printing image collecting element 7 runs through the pressure zone between the coating roller 40 and the countercylinder 15 and a layer of varnish is thereby applied to the element 7. The element 7 thereafter runs through the effective zone of the first drier 37, where drying of the varnish layer commences. Thereafter, the element 7 runs through the pressure zone between "the printing cylinder 9 and counterpressure cylinder 12 of the first printing unit and takes over the printed image of the first colour.

The further colours are then applied in the same mode and manner in accordance with the number of printing units. The printing ink in that case penetrates slightly into the varnish layer so that splitting-back and doubling do not occur in the following printing - 10 unit. Before contact takes place between the central Printing cylinder 4.1 and the printing image collecting element, the applied layer of varnish inclusive of the applied ink from the element 7 is liquified through supply of heat by means of the second drier 38 so that the layer of varnish is almost completely separable from the blanket and the ink is transferable completely, being transferred to the sheet on the passage through the pressure zone between the cylinder 4.1 and the printing element 7. Thereafter, the sheet is conducted to the sheet deposit device 5. The printing of a web takes place in analogous manner.

In the construction for first and perfecting form printing, a transfer of the sheet to the perfecting cylinder 29.1 takes place after printing of the first sheet line and the printing of the rear side of the sheet takes place by perfecting equipment 28 in the form of a known single printing unit 28.1 or a further printing image collecting - element 28.2 in the described mode and manner. Thereafter, the sheet is conducted to the sheet deposit device 5. Perfecting takes place analogously in the roller machine.

The advantages of this system lie in the simple sheet guidance even in first and perfecting form printing in the printing without doubling problems, and in the minimum number of ink g-aps.

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Claims

- 11 CLAIMS 1. A printing machine comprising sheet or web material feed

means, sheet or web material discharge means, cylinder means to transfer sheet or web material from the feed means to the discharge means, an endless, printing image collecting element contacting the cylinder means, at least one printing unit co-operable with the endless element and comprising a printing cylinder, a counterpressure cylinder and inking and moistening means, varnishing means co-operable with a countercylinder and arranged upstream of the printing unit or units with res- pect to a direction of travel of the endless element towards the cylinder means, a first drier arranged upstream of the printing unit or units with respect to said direction, and a second direr arranged downstream of the printing unit or units with respect to said direction, the endless element extending through a pressure zone between the printing and counterpressure cylinders of the or each unit, through a pressure zone between the varnishing means and the countercylinder, and through drying zones of the driers.
2. A printing machine as claimed in claim 1, the cylinder means comprising a central printing cylinder provided with gripper means for gripping sheets.
3. A printing machine as claimed in claim 2, comprising perfecting means arranged downstream of the central printing cylinder with respect to a direction of movement of sheets from the feed means to the discharge means, the perfecting means comprising at least one perfecting cylinder and a drum system which forms part of the cylinder means.
4. A printing machine as claimed in claim 1, the cylinder means comprising a central printing cylinder arranged to guide a web from the feed means to the discharge means.
5. A printing machine as claimed in claim 4, comprising perfecting means arranged downstream of the central printing cylinder with respect to a direction of movement of the web from the feed means to the discharge means, the perfecting means comprising at least one perfecting cylinder and a drum system which forms part of the cylinder means.

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6. A printing machine as claimed in claim 3, wherein the perfecting cylinder is provided with gripper means for gripping sheets.
7. A printing machine as claimed in claim 6, the perfecting means further comprising a transfer cylinder provided with gripper means for gripping sheets.
8. A printing machine as claimed in claim 3, whereih the drum system comprises two transfer cylinders selectably usable for sheet turning and sheet transport.
9. A printing machine as claimed in claim 3, wherein the drum system comprises four transfer cylinders selectably usable for sheet turning and sheet transport.

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10. A printing machine as claimed in either claim 3 or claim 4, the perfecting means being constructed as a single printing unit comprising a printing cylinder, inking and moistening means, and an offset cylinder disposed in pressurable contact with the printing cylinder of that unit and with the drum system.
11. A printing machine as claimed in either claim 3 or claim 5, the perfecting means being constructed as a further such endless, printing image collecting element and a further such printing unit, the further element pressurably contacting the drum system and extend- ing through a pressure zone between the printing cylinder and counterpressure cylinder of that further unit.
12. A printing machine as claimed in claim 1, wherein the printing cylinder of said at least one printing unit is arranged above an upoer run of the endless element.
13. A printing machine as claimed in claim 1, wherein the printing cylinder of said at least one printing unit is arranged below a lower run of the endless element.
14. A printing machine as claimed in claim 12, comprising a further such printing unit co-operable with the endless element, the printing cylinder of the further unit being arranged below a lower run of the endless element.
15. A printing machine as claimed in any one of claims 1 to 10, wherein the endless element has the form of an offset blanket.
16. A printing machine as claimed in any one of claims 1 to 10, wherein the endless element is provided with at least one offset blanket portion.
17. A printing machine as claimed in any one of claims 1 to 10, wherein the endless element is provided with at least one gripper for an offset blanket portion.
18. A printing machine as claimed in any one of the preceding claims, the varnishing means comprising a varnish trough, a coating roller, a varnish metering roller and a varnish scoop roller.
19. A printing machine as claimed in any one of the preceding claims, wherein the first drier is an initial drier.
20. A printing machine as claimed in any one of the preceding claims, wherein the second drier is an energy drier.
21. A printing machine substantially as hereinbefore described with reference to Fig. 1 of the accompanying drawings.
22. A printing machine substantially as hereinbefore described with reference to Fig. 2 of the accompanying drawings.

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23. A printing machine substantially as hereinbefore described with reference to Fig. 3 of the accompanying drawings.
24. A printing 'Machine substantially as hereinbefore described with reference to Fig. 4 of the accompanying drawings.
25. A printing machine substantially as hereinbefore described with reference to Fig. 5 of the accompanying drawings.
26. A printing machine substantially as hereinbefore described with reference to Fig. 6 of the accompanying drawings.
27. A printing machine substantially as hereinbefore described with 10 reference to Fig. 7 of the accompanying drawings.
28. A printing machine substantially as hereinbefore described with reference to Fig. 8 of the accompanying drawings.
29. A printing machine substantially as hereinbefore described with reference to Fig. 9 of the accompanying drawings.
30. A printing machine substantially as hereinbefore described with reference to Fig. 10 of the accompanying drawings.
31. A printing machine substantially as hereinbefore described with reference to Fig. 11 of the accompanying drawings.

Published 1989 at rn).e Patent Office, State House, 66 71 Rigb Holborn, London WCIR 4TP. Further 0OPles maybe obtained from The Patent Offtce. Sales Branch, St Mary Cray, Orpington, Kent BR5 3RD. Printed by Multiplex techniques ltd, St M&ry Cray, Kent, Con. 1/87