EP3720717B1 - Processing machine comprising a unit having a storage container and method for operating a storage container - Google Patents

Description

The invention relates to a processing machine, in particular a printing machine, with a work with a storage container and a method for operating a storage container in a work of a processing machine, in particular a printing machine.

An ink fountain conventionally comprises a ductor roller and an ink fountain base, which delimit an ink chamber that is filled with ink, in particular UV printing ink, during operation. Along a lower edge of the ink fountain base, several paint slides are arranged in a row, which together with the ductor roller on the ink fountain arch of the ink chamber form a gap through which color is conveyed out of the ink chamber by rotating the ductor roller. The distance between the paint slider and the ductor roller determines the thickness of the paint layer conveyed out of the paint chamber. This distance can be adjusted individually for each paint slider, so that a paint layer of variable thickness is obtained.

Since the paint slides are in direct contact with the paint in the paint chamber and must be movable relative to one another, there is the possibility that paint will penetrate into a gap between a side part and a paint slide or between two paint slides and make it more difficult to clean the paint fountain when changing the color or even hinders the adjustment of the color sliders. To prevent this, the paint sliders are currently greased during assembly so that grease in the gaps between the side panels and paint sliders and between the paint sliders blocks the path of the paint. Since the fat turns into the color over time, regular greasing is necessary.

From DE - Gbm 69 47 168 or DE-OS 1 961 033 a sealing device on ink rollers for printing machines is known, with a sealing surface with an annular recess for air under excess pressure preventing ink transfer being provided between a fixed sealing frame and a ductor roller.

From the DE 32 41 124 A1 an ink compartment wedge in an ink fountain of a rotary printing machine is known, with a sealing end face adapted to an ink fountain roller being provided with a longitudinal groove into which bores open, which are connected to a compressed air source via hoses.

From the WO 2017/121852 A1 a sealing element for a doctor chamber of a flexographic printing machine is known, wherein a sealing surface resting on a roller body has a flow outlet opening at which an excess pressure of a fluid can be built up during operation of the machine in such a way that the fluid forms a sealing flow film between the sealing surface and the roller body.

From the DE - AS 1 269 138 an ink fountain for a printing press with a flexible ink knife is known, a pneumatically actuated body extending along the ink knife being attached below the ink knife and a force counteracting the pneumatic pressure being able to be generated locally via individually adjustable elements.

With the solutions mentioned, a sealing effect cannot be achieved in the area of sliders, in particular paint sliders, or between sliders and side walls. DE 102007003943 discloses a printing press with a printing unit comprising an ink fountain.

The invention is based on the object of creating alternative processing machines with a work or an alternative method for operating a storage container in a work, in particular a printing work, of a processing machine.

The invention has the advantage that an alternative processing machine, in particular printing machine, with a work with a storage container or an alternative method for operating a storage container in a work, in particular printing work, is provided. In particular, a processing machine, in particular a sheet-fed and/or offset printing machine, with a corresponding work, in particular a printing unit, is provided.

The invention is defined in independent claims 1 and 11. Advantageous embodiments are defined in the respective dependent claims.

Fig. 1:

einen schematischen Schnitt I - I durch einen Farbkasten entlang einer ersten zur Achse der Duktorwalze senkrechten Ebene;

Fig. 2:

einen schematischen Schnitt II - II durch einen Farbkasten entlang einer zweiten zur Achse der Duktorwalze senkrechten Ebene;

Fig. 3:

einen Teilschnitt durch einen Farbkasten entlang einer von der Achse der Duktorwalze aufgespannten Ebene;

Fig. 4:

Ausführung einer bedienseitigen Stirnwand eines Farbkastens;

Fig. 5:

Ausführung einer antriebsseitigen Stirnwand eines Farbkastens.

The invention will be explained below by way of example. The associated drawings show schematically:

Fig. 1:

a schematic section I - I through an ink fountain along a first plane perpendicular to the axis of the ductor roller;

Fig. 2:

a schematic section II - II through an ink fountain along a second plane perpendicular to the axis of the ductor roller;

Fig. 3:

a partial section through an ink fountain along a plane spanned by the axis of the ductor roller;

Fig. 4:

Execution of an operating-side front wall of an ink fountain;

Fig. 5:

Execution of a drive-side end wall of an ink fountain.

In the case of a sheet-processing machine (not shown), for example a sheetfed offset rotary printing machine, especially in aggregate and series design, one or more printing units and possibly one or more coating units can be provided, in which corresponding storage containers are arranged. In particular, in a respective printing unit, a storage container can be designed as an ink fountain, which includes a ductor roller 01, side walls and an ink fountain base 03, which together delimit an ink chamber 04 for printing ink, in particular UV printing ink, which is open at the top. However, a cover or something similar can also be provided over the ink fountain. The machine preferably has a dryer for the printing ink applied to the substrate, in particular printing material, for example sheets or webs of paper, film or the like. In particular, UV dryers or UV intermediate dryers are provided in the machine for drying or curing the preferred UV printing ink.

Via at least one but preferably a plurality of ink slides 06 of the ink fountain arranged along the edge of the ink fountain base 03, together with the ductor roller 01, an ink exit gap 13 is formed for the printing ink, through which the printing ink, for example via a roller mill in the printing unit, is formed into a form or Plate cylinder is conveyed. For example, on a medium-format machine, approximately thirty-five color slides 06 can be placed side by side in one Rows can be arranged so that a corresponding number of individually controllable color zones are formed. For large-format machines, more color slides 06, for example up to forty-nine or more color slides 06, can be used.

For example, the inking unit in the printing unit can be designed as a film inking unit or preferably as a siphon inking unit, with the ductor roller 01 (also called an ink fountain roller) interacting with an ink siphon roller, which transfers the printing ink to the following rollers of the roller mill. The rollers of the roller mill can have known friction and traversing rollers that distribute the printing ink as evenly as possible. The roller mill can also contain inking rollers which are in surface contact with the plate cylinder and which transfer the printing ink to a printing plate stretched onto the plate cylinder. Furthermore, the inking unit can also be designed as an inking and dampening unit with a dampening unit. For example, the ductor roller 01 can have its own drive for driving it during printing operation. In particular, this drive can be designed as an individual ductor drive, which alone drives the ductor roller 01 in rotation. The individual drive can also drive the ductor roller 01 using a transmission gear.

The Fig. 1 shows, for example, an ink fountain for a printing press, in particular a sheet-fed printing press, for example as described above, comprising a ductor roller 01, which is one to the plane of the Figures 1 and 2 vertical axis 02 is rotationally driven in a clockwise direction, and an ink fountain base 03 which slopes towards the ductor roller 01. The ductor roller 01 and ink fountain base 03 form the long sides of an ink chamber 04. End faces of the ink chamber 04 are formed by end walls 05, the cutting plane II extends in one of these end walls 05 - II the Figure 2 . The end walls 05, the ink fountain bottom 03 and/or ink slider 06 of the ink fountain can be in direct contact with the printing ink, in particular UV printing ink. Alternatively, one or more or all of these elements can be in direct contact with the paint in the paint fountain, for example via a film or the like.

At least one and in particular several ink slides 06 are preferably arranged in a row along the lower edge of the ink fountain base 03 facing the ductor roller 01. The paint slides 06, for example, each have an approximately cuboid-shaped head 07 with an end face that tapers obliquely towards the ductor roller 01 and two flanks 08 oriented perpendicular to the axis 02 (see Figure 3 ) and a shaft 09 extending radially from the axis 02. The heads 07 of the paint slides 06 are accommodated, for example, in a groove 10 extending in the direction of the axis 02 at the lower edge of the ink fountain base 03; the diameter of the shafts 09 is smaller than that Distance between the flanks 08 of a head 07, the shafts 09 run in bores 11 which extend radially away from the axis 02 from the bottom of the channel 10.

One end face of each head 07 is in direct contact with the paint of the ink chamber 04. An edge of this end face facing the ductor roller 01 is preferably formed by a strip 12 made of wear-resistant material such as hard metal. The width of an ink exit gap 13 between the bar 12 and the ductor roller 01 is a few 10 μm. By adjusting the distance between the bar 12 and the lateral surface of the ductor roller 01 (ink exit gap 13), the layer thickness of the printing ink emerging from the ink fountain is set in the relevant ink zone. Some or all heads 07 or color sliders 06 can preferably be designed to be identical.

In particular, a spring 14 is accommodated in the bore 11, which exerts a force directed away from the axis 02 on the paint slide 06 and holds the paint slide 06 in a stop against an adjusting device 16. The spring 14 can in particular be a helical spring which extends around the shaft 09 and is clamped between a shoulder of the bore 11 and a snap ring 15 placed on the shaft 09.

The adjusting device 16 of each ink slider 06 can be actuated independently of the other adjusting devices 16 in order to be able to control the width of the ink exit gap 13 zone by zone. In the case shown here, the adjusting device 16 comprises a pin 18 which can be rotated eccentrically about an axis 17 parallel to the axis 02 and which engages in a fork 19 at the end of the shaft 09 opposite the head 07. Alternatively, the adjusting device 16 can also transmit an adjusting movement to the paint slider 06 in another way, for example via a contoured surface. In particular, an adjusting device 16 can shift or pivot a paint slide 06 about a pivot axis arranged parallel to the axis 02 or rotation axis of the ductor roller 01.

A bore 20 extends through the heads 07 of the paint slides 06 parallel to the axis 02 or rotation axis of the ductor roller 01. The diameter of the bore 20 can be larger than the freedom of adjustment of the paint slides 06 in order to ensure that in every position the paint slides 06 can take relative to each other, their holes 20 overlap.

As in Fig. 3 As can be seen, the bores 20 also overlap with an axial bore 21 in at least one end wall 05. This axial bore 21 communicates with one in the sectional plane of the Figure 2 extending bore 22. The bore 22 ends here, for example, at a pneumatic plug connector 23 on an edge of the end wall 05 facing away from the axis 02. The bores 20, 21, 22 together form a compressed gas line. The connector 23 is provided for connecting a source of compressed air, such as a compressor, via a complementary connector 24. Alternatively, the pneumatic connection can also be made elsewhere or with appropriately suitable connections. The compressed air source can, for example, provide a pressure of at least approximately two bar at the ink fountain.

The flanks 08 of the paint slides 06 and the insides of the end walls 05 opposite a paint slide 06 are preferably polished in order to reduce the width of gaps 25 between the heads 07 and between an end wall 05 and the head 07 adjacent to it, and thus the inclination of the paint the ink chamber 04 to penetrate into the column 25 to minimize. As a rule, it cannot be completely suppressed in this way, since capillary forces promote penetration into the gap 25. However, by applying compressed air to the bores 20 via the bores 22, 21, an air flow directed radially outwards from the bores 20 is maintained in the gaps 25, which creates an excess pressure in the gaps 25 that counteracts the penetration of the paint. In a further development, the air flow emerging in the gap 25 can also be directed or at least partially limited, in particular by shaping the head 07.

The wider the gap 25, the stronger the air flow is, so that any residual waviness in the opposing polished flanks 08 is automatically compensated for by an increased air flow. The requirements for the flatness of the flanks 08 can therefore be lower than with an ink fountain with gaps 25 sealed by a stationary layer of grease.

The end walls 05 each have a concave edge 26 that acts as a sealing surface and is opposite the lateral surface of the ductor roller 01. As between the paint sliders 06, a gap 27 between this edge 26 and the lateral surface should be as narrow as possible in order to prevent the paint from penetrating into the gap 27. According to a preferred embodiment, a tap hole 28 extends between this edge 26 and the hole 22 within the end wall 05, via which compressed air is also supplied to the gap 27. Since the rotation of the ductor roller 01 promotes the spread of air in the gap 27 in the direction of rotation, a starting point 29 of the tap hole 28 can be located at an upper end of the edge 26.

A groove 30 extending in the circumferential direction can be provided on the edge 26 in order to promote the distribution of the compressed air along the edge 26 and to keep the gap 27 free, particularly near its lower end, at a large distance from the starting point 29 of the tap hole 28 to keep color.

In order to simplify the production of the end walls 05, both can be provided with identical bores 21, 22, 28. The axial bore 21 extends from one main surface of the end wall 05 to the other and is provided with a closure 31 at its end facing away from the paint slides 06. Then the bores 20 of the paint slide 06 can also be pressurized with compressed air from both sides. This may be necessary in the event that the bores 20 are so narrow or the overlap between them is so small that when supplied via only one end wall 05 in the bores 20 there is a noticeable drop in pressure over the length of the arrangement of paint slides 06 would occur to ensure an adequate supply of compressed air to all columns 25 and/or columns 27.

However, the air outflow from the bores 20 via the gap 25 or gap 27 should preferably be so small that no significant pressure drop occurs along the bores 20, not least in order to avoid air bubbles rising within the paint of the paint chamber 04, which, if they pass through the ink exit gap 13, this could lead to fluctuations in the ink layer thickness. For example, the gap 25 arranged between two end walls 05 and/or the gap 27 arranged between end walls 05 and ductor roller 01 can be dimensioned such that a pressure drop across the gaps 25, 27 is limited to a value, in particular 25%.

The Fig. 4 shows an embodiment of an end wall 05 of an ink fountain in a printing unit of a processing machine, in particular an offset printing machine, preferably a sheetfed offset rotary printing machine in aggregate and series construction, for example as described above. The end wall 05 can, for example, be arranged on the operating side of the machine and limit the ink chamber 04 of the ink fountain. The end wall 05 has a bore 22 which corresponds to a bore 21 supplying bores 20 of paint slides 06. The bore 21 is here only arranged in the flank 08 of the end wall 05 facing the paint slides 06, and is sometimes not continuous.

A further bore, in particular a tap bore 28, is provided at an angle, in particular orthogonally, to the bore 22, which with a further bore has a starting point 29 for a groove 30 in the sealing surface facing the ductor roller 01, in particular the edge 26 facing the ductor roller 01 End wall 05 forms. The groove 30 runs here in particular along the concave edge 26 of the end wall 05. The starting point 29 is in particular arranged approximately centrally to the groove 30, so that the negative pressure from the starting point 29 is formed evenly along the groove 30. The groove 30 can, for example, have a particularly uniform depth and/or width of approximately 3 mm. The groove 30 can be designed at one end or preferably at both ends with a radius of curvature of, for example, 10 mm. In the embodiment shown, the hole forming the starting point 29 can be made in the end wall 05 at an angle of at least approximately 20° to the horizontal and/or have a diameter of at least approximately 3 mm.

The end wall 05 can have a further hole, as shown here in section AA. This hole can be used additionally or alternatively for the pneumatic supply of the hole 22 in the end wall. If this hole is used for pneumatic supply, the inlet opening of the hole 22 is preferably closed. The entrance opening of the tap hole 28 shown in section BB is also closed when the machine is in operation.

The Fig. 5 shows an embodiment of an end wall 05, in particular of the ink fountain described above. The end wall 05 can, for example, be arranged on the drive side of the machine and limit the ink chamber 04 of the ink fountain. The end wall 05 has a bore 22 which corresponds to a bore 21 supplying bores 20 of paint slides 06. The bore 21 is here only arranged in the flank 08 of the end wall 05 facing the paint slides 06, and is sometimes not continuous.

A further bore, in particular a tap bore 28, is provided at an angle, in particular orthogonally, to the bore 22, which with a further bore has a starting point 29 for a groove 30 in the sealing surface facing the ductor roller 01, in particular the edge 26 facing the ductor roller 01 End wall 05 forms. The groove 30 runs here in particular along the concave edge 26 of the end wall 05. The starting point 29 is in particular arranged approximately centrally to the groove 30, so that the negative pressure from the starting point 29 is formed evenly along the groove 30. The groove 30 can, for example, have a particularly uniform depth and/or width of approximately 3 mm. The groove 30 can be designed at one end or preferably at both ends with a radius of curvature of, for example, 10 mm. In the embodiment shown, the hole forming the starting point 29 can be made in the end wall 05 at an angle of at least approximately 20° to the horizontal and/or have a diameter of at least approximately 3 mm.

The end wall 05 can have a further hole, as shown here in section AA. This hole can be used additionally or alternatively for the pneumatic supply of the hole 22 in the end wall. If this hole is used for pneumatic supply, the inlet opening of the hole 22 is preferably closed. The entrance opening of the tap hole 28 shown in section BB is also closed when the machine is in operation.

The two end walls 05 can each be located laterally, for example Connect the ink fountain base 03 and thereby form the ink chamber 04, which is open at the top, with the ink fountain base 03 and the ductor roller 01, in which the medium, in particular the printing ink, especially UV printing ink, is held. The ink fountain preferably comprises exactly the two end walls 05, which are in particular designed in one piece or in one piece.

Compressed gas, in particular compressed air, is supplied to both end walls 05 via pneumatic connections, for example the plug connectors 23. The compressed gas, in particular the compressed air, can be supplied, for example, through one or two connectors 24 that can be removed from the plug connector 23. A constant pressure of, for example, approximately two bar can be applied on both sides. If necessary, the intensity and/or the duration of action of the compressed gas, in particular the compressed air, can also be adjusted and/or changed. In particular, however, the intensity and/or the duration of action of the compressed gas, in particular the compressed air, is selected such that a sufficiently large air flow is created at all columns 25, 27 of the storage container, in particular the ink fountain, which has a sealing effect against the medium, in particular the printing ink .

The slide or slides, in particular paint slide 06, can also be adjusted while the compressed gas, in particular compressed air, is applied to adjust the outlet gap 13. If there are several slides, in particular paint slides 06, these are individually displaced by separate adjusting devices 16 to adjust the respective exit gap 13, the roller, in particular ductor roller 01, being driven in rotation about the axis 02 during operation of the machine.

Reference symbol list

01

ductor roller

02

axis

03

Paint box bottom

04

Color chamber

05

Front wall

06

Color slider

07

Head

08

Flank

09

shaft

10

gutter

11

drilling

12

strip

13

Color exit gap

14

Feather

15

snap ring

16

Adjusting device

17

axis

18

Cones

19

Fork

20

drilling

21

drilling

22

drilling

23

Connectors

24

Interconnects

25

gap

26

Edge

27

gap

28

tap hole

29

starting point

30

Nut

31

Clasp

Claims (15)

1. Processing machine, in particular offset printing machine, having a printing unit that has an ink fountain,

   wherein the ink fountain comprises a ductor roller (01), an ink fountain base (03), and end walls (05), which delimit an ink chamber (04) for a printing ink,

   wherein the ink fountain is open toward the top, and

   wherein one or more ink slides (06) are arranged along a margin of the ink fountain base (03) in order to form, together with the ductor roller (01), an ink outlet gap (13) for the printing ink,

   characterized in that

   in the region of the ink slide (s) (06) and/or in the region of an edge (26) between an end wall (05) and the ductor roller (01), pneumatic means are provided for sealing the ink chamber (04) with respect to the printing ink,

   wherein, by means of the pneumatic means, a positive pressure, which is elevated in relation to the ambient pressure and which counteracts a penetration of the printing ink, can be and/or is generated in gaps (25) between ink slides (06) and/or in gaps (25) between end walls (05) and ink slides (06), wherein a compressed gas line is formed by means of bore holes (20, 21) in the ink slide (s) (06) and/or in the end walls (05) and in the ink slide(s) (06), and/or can be and/or is generated in gaps (27) between end walls (05) and the ductor roller (01).
2. Processing machine according to claim 1, wherein the pneumatic means extend, in particular uninterrupted, from one end wall (05) that delimits the ink chamber (04) to the opposite end wall (05) that delimits the ink chamber (04).
3. Processing machine according to claim 1 and/or 2, wherein flanks (08) of ink slides (06) and/or of end walls (05) and ink slides (06) lie opposite one another in pairs, parallel to one another.
4. Processing machine according to claim 1, 2 and/or 3, wherein a compressed gas line (20, 21, 22) is provided, via which at least one gap (25) that is delimited by opposing flanks (08) of two ink slides (06) can be pressurized with compressed gas.
5. Processing machine according to claim 1, 2, 3 and/or 4, wherein a compressed gas line (20, 21, 22) comprises bore holes (20) that extend through ink slides (06) from one flank (08) to the other.
6. Processing machine according to claim 1, 2, 3, 4 and/or 5, wherein ink slides (06) are arranged in a row between end walls (05) of an ink fountain, and a gap (25) delimited by opposing flanks (08) of one of the end walls (05) and one of the ink slides (06) can be pressurized with compressed gas via a compressed gas line (20, 21, 22).
7. Processing machine according to claim 1, 2, 3, 4, 5 and/or 6, wherein a compressed gas line (20, 21, 22) comprises a bore hole (21, 22) in at least one end wall (05) of an ink fountain.
8. Processing machine according to claim 1, 2, 3, 4, 5, 6 and/or 7, wherein the ink fountain has exactly two end walls (05) and/or each end wall (05) comprises bore holes (21, 22) of a compressed gas line.
9. Processing machine according to claim 1, 2, 3, 4, 5, 6, 7 and/or 8, wherein the ink fountain has exactly two single-piece end walls (05), and in the end walls (05) branch bore holes (28) are provided for supplying to a groove (30) arranged in a respective sealing surface (27) of an end wall (05) toward the ductor roller (01).
10. Processing machine according to claim 1, 2, 3, 4, 5, 6, 7 and/or 9, wherein a gap (27) between an end wall (05) and the ductor roller (01) is connected to a compressed gas line (20, 21, 22).
11. Method for operating a reservoir in a unit of a processing machine, in particular a printing machine,

    wherein a roller (01) and a base (03) delimit a reservoir chamber (04) of the reservoir for a medium, and

    wherein one or more slides (06) are arranged along a margin of the base (03), in order to form, together with the roller (01), an outlet gap (13) for the medium,

    characterized in that

    in the region of the slide(s) (06), pneumatic means force in compressed gas for the purpose of sealing the reservoir chamber (04) with respect to the medium,

    wherein the compressed gas counteracts a penetration of the medium into gaps (25) between slides (06) and/or into gaps (25) between end walls (05) and slides (06), wherein the compressed gas keeps a gap (25) between flanks (08) of an end wall (05) and a slide (06) and/or gaps (25) between flanks (08) of slides (06) free of the medium, wherein the compressed gas is conducted via bore holes (20, 21, 22), wherein the slide (s) (06) are shifted for the purpose of adjusting the outlet gap (13), and wherein the compressed gas is conducted through overlapping bore holes (20, 21) in every position of the slide(s) (06), and/or

    wherein the compressed gas counteracts a penetration of the medium into gaps (27) between end walls (05) and the roller (01), wherein the compressed gas keeps a gap (27) between an end wall (05) and the roller (01) free of the medium, and wherein the compressed gas is conducted via grooves (30).
12. Method according to claim 11, wherein the compressed gas keeps the region of the slide (s) (06) below the base (03) outside of the outlet gap (13) free of the medium.
13. Method according to claim 11 or 12, wherein the compressed gas is forced in between flanks (08) of an end wall (05) and of a slide (06) that lie opposite one another in pairs, and/or between flanks (08) of slides (06) that lie opposite one another in pairs.
14. Method according to claim 11, 12 or 13, wherein the slide(s) (06) are shifted in the presence of the compressed gas, in order to adjust the outlet gap (13).
15. Method according to claim 11, 12, 13 or 14, wherein the reservoir is an ink fountain, the base (03) is an ink fountain base (03), the reservoir chamber (04) is an ink chamber (04), and the roller (01) is a ductor roller (01), wherein a plurality of ink slides (06) are shifted in a radial direction relative to the ductor roller (01) to control the width of the ink outlet gap (13) zonally.

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