WO2009090037A1 - Printing group for a machine used in the tobacco industry - Google Patents

Abstract

The invention relates to a method and a printing group for applying print marks to a material web (21) of the tobacco industry, especially wrappers, by means of a gravure printing installation (23, 23.1, 23.2, 23.3), the material web (21) being conveyed along a direction of conveyance at a predetermined speed between an impression unit (48) and a printing form cylinder (45), the print marks being applied to the material web (21) by means of the printing form cylinder (45) which has wells or cups that receive and give off the printing ink. The method is developed in that the impression unit (48) interacts with the printing form cylinder (45) during a printing process, when a print mark is applied to the material web (21), in such a manner that during printing a predetermined contact pressure is exerted on the material web (21) and the contact pressure on the material web (21) is reduced during two, especially subsequent, printing processes.

Description

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Printing unit of a machine of the tobacco processing industry 5 Description

The invention relates to a method for applying print marks to a strip of material of the tobacco-processing industry, in particular wrapping strips, by means of a printing device operating according to the deep-o printing method, wherein the strip of material is conveyed along a conveying direction at a predetermined speed between a counter-pressure member and a printing form roller, wherein the print marks are applied to the strip of material by means of the printing form roller having ink receiving and dispensing grooves or wells.

Moreover, the invention relates to a printing unit of a machine of the tobacco-processing industry for applying Druckmarkeo on a strip of material in the tobacco-processing industry, in particular wrapping strips, wherein the printing unit works or forms according to the gravure printing method, wherein the material strip is conveyed or conveyable along a conveying direction at a predetermined speed between a counter-pressure element and a printing-form roller, the printing-form roller has ink-receiving and dispensing depressions or cups, in contact between the depressions or

Cup and the strip of material printing ink is discharged onto the strip of material. Furthermore, the invention relates to a machine of the tobacco-processing industry, preferably cigar extruder, and a use of a printing unit in a machine of the tobacco-processing industry.

In the tobacco processing industry, stranding machines are used to make continuous, wrapped strands, e.g. Tobacco strands, used. Under a wrapped strand is predominantly understood in particular an endless filter strand or tobacco rod formed from tobacco, which is provided with a wrapping strip or strip of material made of paper, foil or the like.

On the wrapping strip of the tobacco processing industry, e.g. Rolls of cigarette paper, are used in the continuous strand machines, in which rod-shaped

Articles such as cigarettes, cigarillos, cigars or filter rods or the like are produced in the strand process, applied print marks or printed images, which may be, for example, the cigarette brands themselves, but also manufacturer's name or other indications.

The extrusion machines of the tobacco-processing industry contain printing units in which at least one driven stamp press roll is in contact with a counterpressure roll, the web to be printed being guided between the rolls. At the time of printing, the stamps of the stamp printing zen with the continuously moving or conveyed material webs in synchronous operation to apply a mark, lettering or brand logo on the strip of material. Such imprints or stamps are conspicuous quality features of such articles and require special attention with regard to the components and production conditions required for its production, such as the type and condition of the ink used and its feeding, transfer and distribution by several rolls until applied to the wrapping strip.

Printing units of machines of the tobacco processing industry are disclosed for example in EP-A-1 125 737 or EP-A-1 415 805. In addition, DE-A-10 2005 035 701 also describes a printing unit of a machine of the tobacco processing industry.

Moreover, EP-A-1 637 325 describes a method for printing a wrapping strip of a smoking article, wherein a printing unit is used for printing the wrapping strip, which works according to the gravure printing method.

Based on this prior art, the object of the present invention is to improve the printing of wrapping strips of the tobacco processing industry according to the gravure printing method, the design effort should be kept as low as possible.

This object is achieved by a method for applying print marks on a strip of material of the tobacco-processing industry, in particular wrapping strips, by means of a working according to the gravure printing device, wherein the

Material strip along a conveying direction at a predetermined speed between a counter-pressure member and a Printing form roller is conveyed, wherein the print marks by means of the printing form roller, the ink receiving and dispensing recesses or wells are applied to the strip of material, which is further developed by the fact that during a printing operation when applying a print mark on the

Material strip, the counter-pressure member with the pressure forming roller cooperates such that during the printing operation, a predetermined pressing pressure is exerted on the strip of material, and between two, in particular successive, printing the contact pressure on the strip of material is reduced or is.

The printing according to the gravure printing method is based on the fact that the printing of a print mark on the strip of material takes place from a printing forme or a printing forme roller whose printing

Parts are deepened. Such printing parts are ink-receiving depressions or wells in the outer shell of the printing form roller. In this case, the paper to be printed or the material strip is printed and simultaneously conveyed between the hard printing form roller with its depressions as a color memory and a counterpressure roller which has an outer jacket made of rubber or the like. The material strip is in this case pressed by means of the counter-pressure roller with a high pressure on the printing form roller. Both the printing form roller and the counterpressure roller are round in cross-section, being constantly in paper engagement.

When installing a gravure printing unit in a machine of the tobacco processing industry has been found that by the printing unit, consisting of a circular in cross-section

Counterpressure roller and the circular cross-section of the printing form roller, a further pair of draw rollers in the paper path of a bedruck to cigarettes paper strip is present, since the two rollers are always pressed against each other. By each additional Zugwalzenpaar the printing unit increased regulatory burden on the position of the print marks on the strip of material in particular the position of the print marks in several colors is required to achieve or ensure an exact location of the print marks.

The idea according to the invention is based on simplifying the control effort for a precise adherence to the position of the print marks in that the counterpressure member for the printing form roller is temporarily out of engagement with the material strip to be conveyed or printed, whereby upon application of a print mark (printing phase) the material strip is pressed by the counter-pressure element as a pressure roller against the printing form roller. Subsequently, after the application of the print mark and after the removal of ink from the cups of the printing forme roller, the pressing pressure on the material strip (conveying phase) is reduced, so that the material strip is not drawn or conveyed for a predetermined period of time by the counterpressure member and the printing form roller. This means that between two printing operations, the material strip to be printed in the area of the printing forme roller or the counterpressure element is preferably conveyed freely, resulting in a simple position control due to the disengagement between the counterpressure member and the pressure roller in the conveying phase and before or after locations of the printed images the roller while it is not engaged results.

For this purpose, it is further advantageously provided that the pressing pressure on the strip of material, in particular oscillating, is varied.

It is particularly advantageous if between two printing operations no pressing pressure is exerted on the strip of material in the region of the printing unit or of the counter-pressure element and of the printing-form roller. As a result, the function of printing on the material strip is completely separated from the function of (pressure-free) paper feed. In that during the time of not printing the

Material strip is conveyed pressure-free in the field of printing form roller and thus the counter-pressure member and the printing form roller are not in engagement with each other, a simple position control is achieved because during the non-printing phase, no tensile force is exerted on the strip of material. In particular, between the successive printing operations, the contact of the strip of material is interrupted with the gravure form roller, whereby, for example, a taste of the material strip is reduced by a color film on the printing form roller.

In particular, it is provided in an advantageous development that the counter-pressure member has at least one pressing surface, which is preferably rotated synchronized with the printing form roller or the printing areas of the printing form roller.

Moreover, it is advantageous if, during the printing process, i. when applying a print mark on the material strip, the at least one pressing surface of the counter-pressure element and the ink-emitting depressions or wells of the pressure form roller cooperate so that ink is discharged from the wells or wells on the strip of material.

Moreover, a development of the method is characterized in that between two printing operations, the contact between the strip of material and the printing form roller is interrupted, whereby the contact of the strip of material with the gravure roll or the printing form roller is also interrupted. Moreover, it is advantageous if between two printing operations, the contact between the strip of material and the counter-pressure member is interrupted or so that the strip of material is neither conveyed nor drawn nor pressed during the phases of non-printing by the counter-pressure member.

Furthermore, the object is achieved by a printing unit of a machine of the tobacco-processing industry for applying print marks on a strip of material of the tobacco processing

Industry, in particular wrapping strips, wherein the printing unit works or is formed according to the gravure printing method, wherein the strip of material is conveyed or conveyable along a conveying direction at a predetermined speed between a counter-pressure member and a printing form roller, the pressure form roller ink receiving and dispensing depressions or wells, at Contact between the wells or wells and the strip of material printing ink is discharged onto the strip of material, which is further developed in that the counter-pressure member is formed such that during a

Printing process when applying a print mark on the strip of material by means of the counter-pressure member in cooperation with the pressure forming roller, a predetermined pressing pressure is applied and is and between two, in particular successive, printing processes of the pressing pressure is reduced to the strip of material or is.

For this purpose, it is advantageous if the pressing pressure caused by the counterpressure member is varied, in particular oscillating, or variable, so that during a printing process the material strip with an increased pressing pressure by the counterpressure member onto the surface of the pressure forming roller is pressed and then during the phase of Nichtdru- ckens the pressing pressure is reduced or is. For the subsequent printing phase of the pressing pressure on the strip of material is increased accordingly again.

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In particular, no pressure is exerted on the strip of material during the non-printing phase. Preferably, for this purpose, the counter-pressure element is designed as a non-circular or non-circular rotational body in cross-section. It should be noted that o is understood to mean a rotating body which is non-circular in the (vertical) cross-section to the rotation axis. not rotationally symmetrical, is formed.

For this purpose, it is further provided that the rotational body ellipsenförmig5 and / or is formed with flats and / or with recesses, whereby a non-circular in cross-section rotary body is formed. In addition, the rotary body has a, in particular circular arc-shaped or curved, outer pressing surface, which is during the printing operation in engagement with the bedru-ockenden strip of material, so that during the printing phase of

Material strip is pressed onto the printing form roller.

According to a development of the printing unit is also provided that the counter-pressure member on its the material strip 5 contacting outer surface, which is preferably formed circular arc or curved, rubberized or elastic.

In order to apply imprints or print marks at predetermined intervals on the material strip, it is also advantageous if the counter-pressure element and the pressure-forming roller are or are driven synchronized. In addition, the object is achieved by a machine of the tobacco-processing industry, preferably cigarette extruder machine, which is formed with a printing unit according to the invention.

A further solution of the problem is to use a printing unit described above in a machine of the tobacco-processing industry. To avoid repetition, reference is expressly made to the above statements.

The invention will be described below without limiting the general inventive idea using exemplary embodiments with reference to the drawings, reference being expressly made to the drawings with respect to all unspecified in the text according to the invention Einzelhei-. Show it:

Fig. 1 shows a cigarette rod machine of the type "PRO¬

TOS "of the Applicant in a schematic view;

2 is a schematic view of an inventive printing unit of the cigarette rod machine;

Fig. 3a, 3b schematically an inventive printing unit in a printing position and in a non-printing position and

4a to 4e different embodiments of a counter-pressure element, wherein in Fig. 4a a Gegendruckor- gan in the form of a counter-pressure roller is shown as prior art. In the following figures, identical or similar elements or corresponding parts are provided with the same reference numerals, so that a corresponding renewed idea is dispensed with.

In the case of the cigarette rod maker PROTOS of the patent applicant, shown schematically in FIG. 1, a pre-distributor 2 is supplied in portions with tobacco from a lock 1. A removal roller 3 of the pre-distributor 2 added controlled a reservoir 4 with tobacco, from which a steep conveyor 5 takes tobacco and a

Stowage 6 controlled feeds.

From the storage shaft 6 takes a pin roller 7 a uniform stream of tobacco, which is knocked out by a rollover roller 8 of the pins of the pin roller 7 and thrown on a circulating at a constant speed spreading cloth 9. A tobacco fleece formed on the spreading cloth 9 is thrown into a sighting device 11, which consists essentially of an air curtain, the larger or heavier tobacco particles pass, while all other tobacco particles from the air in a funnel formed by a pin roller 12 and a wall 13 14th be steered.

From the pin roller 12, the tobacco is thrown into a tobacco channel 16 against a rope conveyor 17, where the tobacco held by means sucked into a vacuum chamber 18 air and a tobacco rod is aufauert.

An equalizer 19 removes excess tobacco from the tobacco rod, which is then placed on a run in synchronized cigarette paper strip 21. The cigarette paper strip 21 is withdrawn from a reel 22, passed through a printing unit 23 and placed on a driven format tape 24. The format tape 24 transports The tobacco rod and the cigarette paper strip 21 through a format 26, in which the cigarette paper strip 21 is folded around the tobacco rod, so that even an edge protrudes, which is glued by a Glimapparat, not shown in a known manner. Then the bond is closed and dried by a Tandemnahtplätte 27.

A coated tobacco rod 28 formed as a material strand passes through a strand density meter 29 which controls the leveling device 19 and is rotated twice in length by a knife apparatus 31

Cut cigarettes. The double-length cigarettes are transferred from a controlled arms 33 having transfer device 34 of a transfer drum 36 of a Filteransetzmaschine 37, on the cutting drum 38, they are divided with a circular blade in single cigarettes.

Conveyor belts 39, 41 promote excess tobacco in a arranged from the reservoir 4 container 42, from which the recycled tobacco is removed from the vertical conveyor 5 again.

Fig. 2 shows schematically a view of a printing unit 23 according to the invention of a cigarette rod machine omitting erfindungsunwesentlicher details. From the reel 22, the cigarette paper strip 21 is withdrawn as a material strip of the tobacco-processing industry, for example by means of a take-off roller pair, and conveyed to the printing unit 23 according to the invention via various deflection rollers. Here, the cigarette paper strip 21 is conveyed through the printing unit 23 linearly or horizontally at a constant speed, so that print marks are applied to the cigarette paper strip 21 at equidistant intervals after passage of the cigarette paper strip 21 through the printing unit 23. On the input side of the printing unit 23, the cigarette paper strip 21 is conveyed via a deflection roller 43 to the printing units 23.1, 23.2 and 23.3 of the printing unit 23. Due to the fact that several printing units 23.1 to 23.3 are present in the printing unit 23, it is possible to apply a multicolored imprint on the cigarette paper strip 21, wherein each of the printing units 23.1, 23.2, 23.3 imprints a predetermined color on the strip.

The printing units 23.1 to 23.3 are functionally the same, so that in the present case only the printing unit 23.1 will be described in detail. The following remarks on the printing unit 23.1 apply analogously to the further printing units 23.2 and 23.3.

The printing unit 23.1 has an ink reservoir 44 with printing ink, from which printing ink is removed by means of a printing form roller 45. The ink can be picked up from the ink supply 44 directly from the printing form roller 45, as shown in Fig. 2, or indirectly, i. with the interposition of ink-carrying rollers or cylinders (not shown here) between the ink reservoir 44 and the printing form roller 45 are removed.

The printing form roller 45 itself has on its hardened surface wells or depressions in which the printing ink from the

Ink supply 44 is included. The ink adhering in the recesses or wells of the printing form roller 45 is further conveyed, so that the surface of the printing form roller 45 comes into engagement with a doctor blade 46, whereby excess printing ink is doctored off from the surface of the printing form roller 45.

As a result, the printed image vacancies between the wells are cleaned by means of the doctor blade 46 by excess printing ink be scraped off.

Subsequently, the ink receiving cups are conveyed on the printing form roller 45 in the contact area with the cigarette paper strip 23 or in the printing area, so that the ink is applied from the wells to the underside of the simultaneously conveyed cigarette paper strip 21 and thereby an imprint on the cigarette paper strip 21 produced by delivery of the ink.

During the printing phase, the cigarette paper strip section, which is simultaneously conveyed and to be printed, is pressed onto the surface of the printing form roller 45 by a rotary counterpressure body 48 in the area of the printing area. The printing form roller 45 and the rotary counterpressure body 48 are driven in opposite directions to rotate.

The rotary counterpressure body 48 is synchronized with the printing form roller 45, which is driven in rotation about its axis of rotation 47, or the ink receiving or dispensing cups of the printing form roller 45 is rotated about its axis of rotation 49. The Rotationsgegendruckkörper 48 is in this case non-circular in cross section, so that are pressed for or during the printing phase of the cigarette paper strip portion to be printed in the region of the printing area with a predetermined pressing pressure on the wells of the printing form roller 45 so that ink from the wells on the cigarette paper strip 21st is delivered.

The printing unit 23 is a printing unit, which operates according to the gravure printing method, according to the invention instead of known in the art, in cross-section round counter-pressure roller as Pressurizer in non-circular cross-section rotary back pressure body is used as counter-pressure element for the printing form roller 45. In accordance with the invention, a predetermined pressing force is exerted on the strip of material for the time of the printing phase by the rotary counterpressure body 48 as a pressure roller, while in the

Non-printing phase of the cigarette paper strip 21 is pressed less or not at all by the rotary back pressure body 48 for a predetermined period of time against the surface of the printing form roller 45. 0

In particular, in the time between two printing operations no ink is discharged from the printing form roller 45 to the cigarette paper strip 21, wherein preferably in this case smooth surface areas of the printing form roller 45 are conveyed without wells through the printing area. Preferably, the

Surface of the printing form roller 45 is formed such that the print image or print mark giving areas with wells are arranged on the surface of the printing form roller 45 at regular intervals, while between the print image giving 0 areas, the surface of the printing form roller 45 is smooth.

According to the embodiment of the printing unit 23 shown in Fig. 2 with the working in gravure printing units 23.1 to 23.3, it is possible that the ink supplies 44 of Druckein-5 units 23.1 to 23.3 have different colors, so that a multi-colored print or a multi-color print mark is applied to the cigarette paper strip 21. After application of the print marks, the cigarette paper strip 21 is further conveyed so that a formed tobacco rod is enveloped by the printed cigarette paper strip.

In the figures 3a and 3b are schematic views of a 3a, whereby in the position of the printing unit 23 shown in FIG. 3a a printed mark is printed on the cigarette paper strip 21, whereas according to the position shown in FIG. 3b no printing of a printed mark on the cigarette paper strip 21 takes place and the cigarette paper strip

21 is conveyed without pressing pressure in the pressure range between the rotary back pressure body 48 and the printing form roller 45.

The Rotationsgegendruckkörper 48 is in this embodiment example elliptical or elongated or flattened or in the manner of an ellipse, i. elliptical, formed. Since the diameter of the rotational counter-pressure body 48 is not constant, this provides a cross-sectionally non-circular impression roller, so that during the printing phase (see Fig. 3a) the cigarette paper strip 21 is pressed against the ink-receiving cells of the printing form roller 45, subsequently during the non-printing phase with further rotation of the rotary back pressure body 58 to lower the pressing pressure (to zero), so that with further promotion of the cigarette paper strip 21 in an advantageous embodiment of the cigarette paper strip 21 no touching contact with the

Surface of the printing form roller 45 has (see Fig. 3b). Preferably, a cup-free zone is rotated below the cigarette paper strip 21 between two printing operations, so that subsequently with further rotation of the printing form roller 45 and the rotary back pressure body 48 synchronized the

Ink-receiving wells of the printing form roller 45 together with the pressing surface 51 in the region of the vertices 52 presses the strip of material against the surface of the printing form roller 45 and whose cups.

In Fig. 4a, a counter-pressure roller 55 according to the prior art is shown in cross section. The counterpressure roller 55 is in Cross-section circular or circular, wherein the counter-pressure roller 55 on the outer side or outer surface 56 has an elastic sheath made of rubber or the like.

FIGS. 4b to 4e show exemplary embodiments of rotary counterpressure bodies 48 according to the invention which are used instead of a counterpressure roller 55 (cf., FIG. 4a) in a gravure printing unit according to the invention in a machine of the tobacco-processing industry.

The rotary counterpressure body 48 in FIG. 4b has a recess 54 on its outer lateral surface or outer surface 56, so that the rotary counterpressure body 48 has a non-circular cross-section. Through the recess 54 is under rotation of the counter-pressure member in an inventive

Printing unit reduces the contact pressure of the cigarette paper strip to be printed relative to the circular lateral surface, so that upon rotation of the recess 54 through the printing area of the cigarette paper strip with less contact pressure or no contact pressure is conveyed through the printing area.

4c shows the embodiment of a rotary counterpressure body according to the invention, which has flattened portions 53 in cross-section on two sides.

The rotational counterpressure body shown in FIG. 4d is designed in the manner of a sleeve or rods rotating in the middle, wherein the outer surfaces 56 are designed spherically in the manner of a circular arc, which interacts with the pressure forming roller 45 during the printing process. 4e shows a one-armed rotary counterpressure body 48, which is also non-circular in cross-section, wherein the outer side 56 has a rubberized surface which comes into contact with the cigarette paper strip when a print mark is applied.

LIST OF REFERENCES

1 lock

2 pre-distributors

3 removal roller

4 storage containers

5 steep conveyors

6 stowage night

7 pin roller

8 deflection roller

9 sprinkler

11 viewing device

13 band

14 funnels

16 tobacco channel

17 strand conveyors

18 vacuum chamber

19 equalizer

21 cigarette paper strips

22 Bobine

23 printing unit

23.1 printing unit

23.2 Printing unit

23.3 Printing unit

24 format tape

26 format

27 tandem squares

28 wrapped tobacco rod

29 strand density meter

31 Knife apparatus

33 arms

34 transfer device 36 transfer drum

37 filter attachment machine

38 cutting drum

39 conveyor belt

41 conveyor belt

42 containers

43 pulley

44 color supply

45 printing form roller

46 squeegee

47 rotation axis

48 counterpressure body

49 rotation axis

51 pressing surface

52 vertex

53 flattening

54 recess

55 counterpressure roller

56 outer surface

Claims

Printing unit of a machine of the tobacco processing industry patent claims 1. A method for applying print marks on a strip of material (21) of the tobacco-processing industry, in particular wrapping strips, by means of a printing device according to the Tiefdruckver- (23, 23.1, 23.2, 23.3), wherein the strip of material (21) along a conveying direction a predetermined speed between a counter-pressure member (48) and a printing forme roller (45) is conveyed, wherein the print marks by means of the printing forme roller (45), the ink receiving and dispensing recesses or Cups, are applied to the material strip (21), characterized in that during a printing operation when applying a print mark on the material strip (21) the counter-pressure member (48) with the Druckformwal- ze (45) cooperates in such a way that during the printing process predetermined pressing pressure on the strip of material (21) is exercised, and between two, in particular aufei- subsequent, printing operations of the pressing pressure on the strip of material (21) is reduced or is. 2. The method according to claim 1, characterized in that the pressing pressure on the material strip (21), in particular oscillating, is varied. 3. The method according to claim 1 or 2, characterized in that no pressure is exerted on the material strip (21) between two printing operations. 4. The method according to any one of claims 1 to 3, characterized in that the counter-pressure member (48) has at least one pressing surface (52), which is preferably synchronized with the printing form roller (45) is rotated. 5. The method according to claim 4, characterized in that during the printing operation, the at least one pressing surface (51) of the counter-pressure element (48) and the ink giving the depressions or cups of the printing forme roller (45) cooperate, so that printing ink from the recesses or wells is discharged onto the strip of material (21). 6. The method according to any one of claims 1 to 5, characterized in that between two printing operations, the contact between the strip of material (21) and the printing form roller (45) is interrupted. 7. The method according to any one of claims 1 to 6, characterized in that between two printing operations, the contact between the strip of material (21) and the counter-pressure member (48) is interrupted or is. 8. Printing unit (23) of a machine of the tobacco-processing industry for applying print marks on a strip of material (21) of the tobacco-processing industry, in particular wrapping strips, wherein the printing unit (23) according to Gravure printing method works or is formed, wherein the material strip (21) along a conveying direction at a predetermined speed between a counter-pressure member (48) and a printing forme roll (45) is promoted, the printing form roller (45) receiving and giving ink Recesses or wells, in contact between the wells or wells and the strip of material (21) ink is discharged onto the strip of material (21), characterized in that the counter-pressure member (48) is formed such that during a printing operation when applying a print mark on the material strip (21) is or is exerted by means of the counter-pressure element (48) in cooperation with the pressure-forming roller (45) and is reduced between two, in particular successive, printing operations of the pressing pressure on the material strip (21). 9. Printing unit (23) according to claim 8, characterized in that the by the counter-pressure member (48) caused pressing pressure on the material strip (21), in particular oscillating, is varied or variable. 10. Printing unit (23) according to claim 8 or 9, characterized in that the counterpressure member (48) onon body as Unrunder Rotati- (48) is formed. 11. Printing unit (23) according to claim 10, characterized in that that the rotary body (48) is ellipsoidal and / or formed with flats and / or with recesses. 12. Printing unit (23) according to any one of claims 8 to 11, characterized in that the counter-pressure member (48) on its the material strip (21) contacting outer surface (56) is formed rubberized. 13. Printing unit (23) according to any one of claims 8 to 12, characterized in that the counter-pressure member (48) and the Printing form roller (45) are driven synchronously or are. 14. Machine of the tobacco processing industry, preferably cigarette rod machine, with a printing unit (23) according to one of claims 8 to 13. 15. Use of a printing unit (23) in a machine of the tobacco-processing industry, wherein the printing unit (23) is designed according to one of claims 8 to 13.