EP0924074B1 - Device for metering a coating fluid for print carriers in a printing press - Google Patents

Abstract

The dosing device includes a first dosing system (13,14) for a first coating fluid associated with the applicator roller (30) and which can be exchanged for a second dosing system (13',14') for a second coating fluid. The first system can be detachably connected to a supply line (20) for the first fluid or the second system can be detachably connected to a supply line (20') for the second fluid but they cannot be mixed up. The first system is functionally connected to a first drain outlet (31) for excess first coating fluid which opens into a first receptacle (25,26) which is coupled to a first return pipe (15,16) for the first fluid having a first suction pump (17,18) while the second system is functionally connected to a second drain outlet for the second fluid opening into a second receptacle (25'26') which is coupled to a second return line (15'16') for the second fluid having a second pump (17',18').

Description

The invention relates to a device for dosing a coating liquid for substrates in a printing press according to the preamble of the main claim.

DE 296 16 686 U1 describes a device for coating substrates known with a liquid, the metering system two separately controllable Liquid circuits assigned to different coating liquids are. Each circuit has a feed pump and a suction pump.

Another device is from DE 43 34 803 C1, preferably for painting units in the printing press. According to this training is a Painting unit designed as a processing unit and has a sheet guide cylinder as an impression cylinder, a forme cylinder and an application roller on. For exact dosing of different coating liquids Viscosity, two dosing systems are interchangeably assigned to the forme cylinder, such that the optionally two rollers as the applicator roller and metering roller Forme cylinders are assigned or a chambered doctor blade with a locked application roller is assigned to the forme cylinder.

According to US-A 4 526 102, a color circulation and washing system for a printing press is known. Two different colors can be fed from separate containers on the line side via a pouring spout into a roller gap. The nip is formed by two ink rollers arranged in parallel according to the squeeze roller principle, the ink rollers being assigned to a plate cylinder. On the face side, collecting troughs are arranged below the inking rollers, which connect a switching valve to the corresponding container for the respective ink on the line side via return lines. The return of the paint takes place according to the principle of gravity back into the corresponding collecting container.
Cleaning fluid can be fed into the feed lines and return lines via a plurality of switching valves via a separate feed line.

For facilities that work on the principle of gravity, it is disadvantageous that when processing fast drying coating media such as e.g. Effect printing ink, dispersion varnish, UV varnish, the line systems themselves clog quickly and thus such facilities only for special media can be used. Another disadvantage is that when changing from Coating liquids also in partial strands of pipes and pumps Remains of the original coating liquid remain can, if a change is to be made. There is then a risk that different coating liquids are mixed with each other, resulting in clumping or loss of Coating liquid can lead.

DE-U-83 27 396 discloses a color return device in an inking unit known a printing press. The inking unit has a one Anilox roller and a metering system formed on inking system. The in Inking unit, e.g. a flushing ink unit, excess printing ink is by means of at least one telescopically displaceable color return channel dissipated to at least one paint tank.

The invention has for its object a device of the beginning to create described type that avoids the disadvantages mentioned, the the mixing of different coating liquids prevented and the consumption of coating liquid noticeable reduced.

The object is achieved by the training features of claim 1 solved. Further training results from the dependent Claims.

A device consists of a for example a blanket or a flexible high-pressure plate-bearing form cylinder, which can be brought into contact with a sheet guide cylinder as a printing cylinder. Furthermore, the device consists of an application roller which can be brought into contact with the forme cylinder and a metering system which can be brought into contact with the application roller. The metering system is either a chambered doctor blade which is functionally connected to a rastered application roller or a metering roller which is connected to the application roller, the coating liquid being supplied via the roller gap in the latter metering system. A coating device has at least two separate circulation line systems for two coating liquids. Each circuit system can optionally be brought into functional connection with a metering system, a feed line with a feed pump being arranged upstream of the metering system and at least one return line with suction pump and reservoir being arranged downstream of the metering system. The feed lines can be connected to the respective dosing system in a manner that prevents them from being mixed up.
Dispersion varnishes on an aqueous basis, liquid printing inks with or without metal pigments and UV varnishes are particularly suitable as coating liquids for the inline processing of printing materials.

The dosing systems that can be used are interchangeable within a coating device. A first metering system for the first coating liquid can thus be coupled to the associated circulatory system and a second metering system can be coupled to the associated circulatory system for the second coating liquid. Each dosing system has at least one outlet for excess coating liquid. At least two collecting containers are fixedly arranged within a coating device and are coupled to return lines. The processes of the metering systems are arranged on them in such a way that they are optionally functionally connected to the first or the second, possibly further, collecting container. Depending on the coating liquid to be processed, the use of the dosing system with the appropriate procedure is determined. Differently arranged processes and their assignment to the corresponding collecting container ensure that every coating liquid flows within the intended circulation system.
This prevents mixing of different coating liquids and reduces consumption.

According to a further embodiment not according to the invention, the exchange of the respective metering system is not necessary if only the processes to the fixed collecting containers on the metering system can be exchanged or swiveled.
For this purpose, in the first embodiment not according to the invention, at least one outlet can be detached from the metering system and exchanged for another outlet with a different arrangement and is assigned to the corresponding collecting container. For this purpose, the metering system is optionally detachably coupled to a feed line for a first coating liquid or a feed line for a second coating liquid. At least one detachably arranged outlet for the first coating liquid or at least one detachably arranged outlet for the second coating liquid is assigned to the metering system in an exchangeable manner. The outlet (for the first coating liquid) is functionally connected to a collecting container which is coupled to a return line for the first coating liquid which has a suction pump. In contrast, the outlet (for the second coating liquid) is functionally connected to a collecting container which is connected to a return line for the second one which has a suction pump
Coating liquid is coupled. Each of the processes has circuit protection for the corresponding collection container.

In the second embodiment, which is not according to the invention, the metering system has at least one outlet which is pivotally mounted. According to the number of collecting containers, the pivotable mounting preferably has latching positions into which the drain associated with the respective collecting container can be pivoted. For this purpose, the metering system can be detachably and reliably connected to either a feed line for a first coating liquid or a feed line for a second coating liquid. The metering system has at least one pivotally arranged outlet for the coating liquids to be processed. In swivel positions, the drain can optionally be brought into functional connection with a first collecting container which is coupled to a return line for the first coating liquid which has a suction pump, or the outlet can be brought into functional connection with a second collecting container which has a return line for the second one which has a suction pump Coating liquid is coupled,
each pivot position of the drain has a circuit protection to the corresponding container.

Both designs not according to the invention are protected in terms of circuitry to prevent mixing to be excluded from different coating liquids.

In order to achieve economical use of the coating liquids, when changing the coating liquid and a necessary cleaning process of a circulation system, the excess coating liquid in the supply line is sucked back out of the supply line into a suitable reservoir for holding the coating liquid. This furthermore avoids loss of coating liquid and at the same time noticeably reduces the consumption of coating liquid. At the same time, the supply line is cleaned with a cleaning fluid, the previous mixing of coating liquid and cleaning liquid being reduced and the consumption of cleaning fluid also being noticeably reduced.
Another advantage is that the cleaning time is significantly reduced. The cleaning system is ready for use with another coating liquid faster.

Fig. 1

eine Druckmaschine mit zwei Einrichtungen zum Beschichten von Bedruckstoffen,

Fig. 2

eine erste Ausbildung der Einrichtung zum Beschichten mit Kreislaufleitungssystem,

Fig. 3

ein Kammerrakel als Dosiersystem,

Fig.4

ein Zweiwalzenwerk als Dosiersystem.

The invention will be explained in more detail using an exemplary embodiment. Show schematically

Fig. 1

a printing press with two devices for coating substrates,

Fig. 2

a first training of the device for coating with a circulation line system,

Fig. 3

a chambered doctor blade as a dosing system,

Figure 4

a two-roll mill as a dosing system.

A printing press is provided with a plurality of printing units 1, preferably offset printing units, formed in series, with the arcuate in the conveying direction Substrates a first coating device 2 and a second coating device 3 are subordinate to the printing units 1. Between Coating devices 2, 3 are for drying the printing materials to be processed a dryer unit 4 is arranged. The second coating device 3 is a boom 5 downstream, which, among other things, by rotating Chain systems 7 is formed, which deposit the sheets on a delivery stack 6. A printing unit 1 consists essentially of a plate cylinder 8, a Blanket cylinder 9 and a sheet guide cylinder 11, here a printing cylinder. An inking unit is assigned to the plate cylinder 8; Dampening unit adjacent to the plate cylinder 8, but this is not discussed in detail here shall be. Between the printing units 1 and the coating devices 2, 3 and the dryer device 4 are each a sheet guide cylinder 10 arranged as a transfer cylinder for the transport of the printing materials.

The first coating device 2 is a coating unit, e.g. for processing Dispersion varnish with pigments on an aqueous basis, formed and consists of a sheet guide cylinder 11 (impression cylinder), one with the sheet guide cylinder 11 contactable forme cylinder 12, which is a flexible high pressure plate as a lacquer form, and a first metering system 13. The first metering system 13 is by a gridable with the forme cylinder 12 in contact Applicator roller 30 and a functionally connected to the applicator roller 30 Chamber doctor blade 27 formed.

The second coating device 3 is also a coating unit, e.g. For processing of water-based dispersion varnish and consists of a Sheet guide cylinder 11 (impression cylinder), one with the sheet guide cylinder 11 contactable forme cylinder 12, which carries a rubber blanket and one second metering system 14. The second metering system 14 is preferably by means of a the blanket-carrying form cylinder 12 contactable applicator roller 30 and a metering roller 32 are formed.

All metering systems 13, 14 are each with a separately controllable circulation system can be coupled for the circulation of coating liquids. So is an interchangeable first metering system 13 with the first circulation system for the first coating liquid can be coupled or a replaceable second dosing system 14 is with the second circulation system for the second coating liquid can be coupled in such a way that there is always a metering system 13, 14 within a coating device 2 or 3 is in operation. Alternatively, inside a coating facility 2 or 3 the first metering system 13 (chambered doctor blade 27, application roller 30) for the metering of the first coating liquid also by a second metering system 13 ', formed by a further chamber doctor blade 27' and applicator roller 30, interchangeable for the metering of the second coating liquid. The two-roll mill (metering roll 32, applicator roll 30) is also a metering system 14 for a first coating liquid by a second metering system 14 'with metering roller 32' and applicator roller 30 for a second coating liquid interchangeable. The metering roller 32 ′ faces the metering roller 32 a changed coating on the coating liquid to be processed is tuned to. Finally, a dosing system 14 or 14 'is also inside a coating device 2 or 3 by means of a metering system 13 or 13 ' interchangeable.

In FIG. 2, a first chamber doctor blade 27 is shown as the metering system 13 for the first coating liquid, which forms the metering system 13 with the application roller 30 with a grid structure. A spacer line 28 is preferably assigned to the doctor blade 27. The spacer line 28 is detachably connected to a feed line 20 for the first coating liquid by means of a mix-up-free coupling 29. The feed line 20 opens into a reservoir 19 for receiving the first coating liquid, an adjustable feed pump 22 being coupled to the feed line 20. The feed pump 22 can be used to deliver the first coating liquid to the metering system 13 and can also be switched as a suction pump in order to suck excess coating liquid back into the reservoir 19 from the feed line 20, including the distance line 28.
The chambered doctor blade 27 has drains 31 in the end region which are functionally connected to collecting containers 25, 26 for the first coating liquid. The collecting containers 25, 26 are part of a fixedly arranged collecting system, which has further collecting containers 25 ', 26' for the second coating liquid. The collecting containers 25, 26 are coupled to return lines 15, 16, which have suction pumps 17, 18, and open into the reservoir 19.
If the second coating liquid is to be processed, the chamber doctor blade 27 is separated from the inactivated supply line 20, including the spacer line 28, and exchanged for the chamber doctor blade 27 '. The chambered doctor blade 27 'is coupled with a feed line 20' and preferably with a distance line 28 'and a coupling 29', which is connected to a reservoir 19 'for the second coating liquid with the interposition of a feed pump 22'. The chambered doctor blade 27 'is essentially identical to the chambered doctor blade 27, but has processes 31' which are functionally connected to the collecting containers 25 ', 26'. The collecting containers 25 ', 26' are coupled to return lines 15 ', 16' with integrated suction pumps 17 ', 18' and are connected to the reservoir 19 '.

While the doctor blade 27 'is used in the metering process, the doctor blade 27 can be cleaned, for example, outside the coating device 2, 3 or maintenance work can be carried out.
4 shows a two-roll mill with an application roller 30 and a metering roller 32. In the end region of a roller gap 24, side doctor blades 33 are arranged on both sides, which are coupled at least on one side to a detachably arranged outlet 31. The outlet 31 is functionally connected to the processing of the first coating liquid with the collecting container 25 (on the opposite side, item 26), the collecting container 25, 26 analogously to the arrangement according to FIG. Fig. 2 are connected to the return line 15, 16, suction pumps 17, 18 and the reservoir 19.
For the processing of the second coating liquid, an outlet 31 ', which is functionally connected to the collecting container 25' or 26 ', is detachably arranged at least on one end face of the roller gap. The collecting containers 25 ', 26' are connected to return lines 15 ', 16', suction pumps 18 ', 17' and the reservoir 19 'for the second coating liquid.

The collecting system formed by the collecting containers 25, 25 'and 26, 26' is fixed arranged within the coating device 2, 3 and is connected to the return lines 15.15 'and 16.16' coupled. When changing the coating liquid the dosing system 13, 13 ', 14, 14' is exchanged as required.

The metering systems 13, 13 'have drains 31, 31' which are arranged differently from the collecting system, so that the chamber doctor blade 27 for the first coating liquid with outlet 31 is also assigned to the collecting container 25 or 26 for the return of excess first coating liquid and the chamber doctor blade 27 'for the second coating liquid with outlet 31' is also assigned to the collecting container 25 'or 26' for the return of the excess second coating liquid.
In a further development, the reservoir 19 is associated with a cleaning agent container 23, from which a cleaning fluid can be fed into the supply line 20 via a switching valve 21 on the line side. For this purpose, a connecting line can be releasably inserted between the supply line 20 and the collecting container 25 or 26, which bridges the chamber doctor blade 27 which has meanwhile been removed. The first circuit system can thus be cleaned, while the second coating liquid can be metered via the second circuit system with the exchanged chamber doctor blade 27 '.
The same principle can also be applied to the second circulatory system. For this purpose, the reservoir 19 'is assigned a cleaning agent container 23', from which the cleaning agent can be fed into the supply line 20 'from the line side via a switching valve 21'. Again, a connecting line can be detachably inserted between the feed line 20 'and the collecting container 25' or 26 'for bridging. The second circuit system can thus be cleaned, while the first coating liquid can be metered via the first circuit system by means of the metering system 13 or 14 used.

REFERENCE NUMBERS

1

printing unit

2

coater

3

coater

4

drying device

5

boom

6

delivery pile

7

chain system

8th

plate cylinder

9

Blanket cylinder

10

Sheet guiding cylinder

11

Sheet guiding cylinder

12

form cylinder

13

first dosing system

13 '

second dosing system

14

first dosing system

15

first return line

15 '

second return line

16

first return line

16 '

second return line

17

first suction pump

17 '

second suction pump

18

first suction pump

18 '

second suction pump

19

reservoir

19 '

reservoir

20

first feed line

20 '

second feed line

21

switching valve

21 '

switching valve

22

feed pump

22 '

feed pump

23

Detergent tank

23 '

Detergent tank

24

nip

25

first collecting container

25 '

second collecting container

26

first collecting container

26 '

second collecting container

27

first chamber doctor blade

27 '

second chamber doctor blade

28

first distance line

28 '

second distance line

29

first clutch

29 '

second clutch

30

applicator roll

31

first process

31 '

second process

32

first metering roller

32 '

second metering roller

33

page squeegee

Claims (7)

1. Device for metering a coating liquid for printed material in a printing press, for at least one coating unit (2, 3) formed by a counter impression cylinder (11), a forme cylinder (12), at least one applicator roller (30) with a metering system (13, 14) which can be set on and off fitted thereto, to which are fitted two separately controllable circulating flow systems with pumps (22, 22', 17, 17', 18, 18') with in each case a feed lead (20) and at least one return flow lead (15, 16) for a first coating liquid received in a reservoir (19) as well as a feed lead (20') and at least one return flow lead (15', 16') for a second coating liquid received in a reservoir (19'), characterised in that the first metering system (13, 14) is releasably connectable in a fashion secure against danger of confusion with the first feed lead (20) and is arranged exchangeable against a second metering system (13', 14') releasably connectable in a fashion secure against danger of confusion with a second feed lead (20'), that the first metering system (13, 14) has at least a first outflow (31) which debouches into a first catch container (25, 26) linked with the return flow lead (15, 16) for the first coating fluid, and that the second metering system (13', 14') has at least a second outflow (31') which debouches into a second catch container (25', 26') linked with the return flow lead (15', 16') for the second coating fluid.
2. Device according to Claim 1, characterised in that the metering system (13) for the first coating liquid is formed by a first chamber doctor (27) and the applicator roller (30) with a rastered structure, that a first spacer lead (28) is releasably arranged at the end on the first chamber doctor (27), and is linkable by means of a first linkage (29) in a fashion secure against confusion with the first feed lead (20), and that the first metering system (13) relative to the first feed lead (20) and to the first outflow (31) with first return flow lead (15, 16) has a separate technical circuit security arrangement.
3. Device according to Claim 1, characterised in that the metering system (13') for the second coating fluid is formed by a second chamber doctor (27') and the applicator roller (30) with raster structure, that a second spacer lead (28') is arranged releasably at the end on the second chamber doctor (27') and is linkable by means of a second linkage (29') with the second feed lead (20') in a fashion secure against confusion, and that the second metering system (13') relative to the second feed lead (20') and to the second outflow (25', 26') with second return flow lead (15', 16') has a separate technical circuit security arrangement.
4. Device according to Claim 1, characterised in that the first metering system (14) for the first coating fluid is formed by a first metering roller (32) and the applicator roller (30), that a first distance lead (21) is arranged on the end face above the roller nip (24) formed by both of the rollers (32, 30) and by means of a first linkage (29) with the first feed lead (20) can be linked in a manner secure against confusion, wherein the first metering system (14) has a separate technological circuit security arrangement relative to the first feed lead (20) and to the first catch container (25, 26) with first return lead (15, 16).
5. Device according to Claim 1, characterised in that the second metering system (14') for the second coating liquid is formed by a second metering roller (32') and the applicator roller (30), that a second spacer lead (28') is fitted on the end over the roller nip (24) formed by both of the rollers (32', 30) and is linkable in a fashion secure against danger of confusion by means of a second linkage (29') with the second feed lead (20'), wherein the second metering system (14') has a separate technical circuit security arrangement relative to the second feed lead (20') and to the second catch container (25', 26') with second return flow lead (15', 16').
6. Device according to Claim 1, characterised in that the freed feed leads (20') following the exchange of the metering system (13, 13', 14, 14') and the respective freed catch container (25, 25', 26, 26') can be bridged by means of a connection lead in order to bring into circulation a cleaning fluid while the feed lead (20, 20') of one of the metering systems (13, 13', 14, 14') as well as the catch container (25, 25', 26, 26') with return flow lead (15, 16, 15', 16') is activated for metering a coating liquid.
7. Device according to at least Claim 1, characterised in that

   the metering system (13, 13', 14, 14') according to choice exchangeably has at least one first outflow (31) arranged releasably for the first coating fluid, or a releasably arranged second outflow (31') for the second coating fluid,

   wherein each outflow (31, 31') has a technical circuit security arrangement relative to the corresponding catch container (25, 26, 25', 26').

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