EP2653301A1 - Method for manufacturing a set of embossing rollers - Google Patents

Abstract

The method involves providing an embossing roller set comprising a male roller (P11) including a male surface structure with structural elements and logo structures and comprising a female roller (M11) with a female surface structure that is associated to the surface structure of the male roller for embossing operation with the male roller. The embossing rollers are used for fine embossing in on-line process, where the associated female surface structure is produced independently of previously produced or physically pre-existing male surface structure. An independent claim is also included for an embossing roller set.

Description

The present invention relates to a method for producing embossing rolls for a device for embossing packaging materials with a set of two rolls, according to the preamble of claim 1 and to a set of embossing rolls produced according to the above method as well as to the use of embossing rolls in a device with two embossing rollers for embossing packaging material.

Packaging films for the tobacco industry or for the food industry have been embossed for quite some time with embossing roll devices, wherein z. For example, so-called inner liners, which are wrapped around a number of cigarettes, or can act as packaging material for chocolate, butter or similar foods, electronic components, jewelry or watches.

The so-called inner liners initially consisted of pure aluminum foils, such as household foils, and these were characterized by the fact that they were carried out between two rolls, of which at least one roller had a relief, the so-called logos. Until about 1980, such a pair of rollers consisted in the majority of a steel roller on which a relief was formed and a counter-roller of a resilient material, such as rubber, paper or Plexiglas. By impressing the relief of the Patrizenwalze in the mating roll = die roll of the mirror image impression was prepared.

For more sophisticated logos, the relief of the patrix roll was transferred to a layer on the die roll and became the recesses corresponding to the raised spots etched out or otherwise worked out. Recently, lasers have been used for this engraving.

Since this production of die rollers is expensive, sat down from about 1980, after the registration of US 5,007,271 by the same Applicant, a so-called pin up pin-up system, wherein two identical steel rollers with a very large number of small teeth intermesh and stamp the paper running in between. Logos are made by removing all or part of the teeth on a roller.

As a result, it has also been possible to produce the so-called satin, whereby the surface receives a dull and thereby also more noble appearance due to the large number of small depressions which have been caused by the teeth.

Parallel to the developments of embossing technology, or the production of embossing rollers, also a change took place in the packaging materials, wherein the originally all-metal aluminum foil was replaced by paper foils, whose surfaces were coated from environmental considerations with ever thinner metal layers, with the last sputtered the metal layer , In more recent times, and also in the future, the metallization of inner liners will become even smaller or disappear altogether.

At the same time efforts are underway, packaged by the classic packaging system cigarettes in inner liners and put this pack in a cardboard housing to get away, so-called soft packs, with only a wrapping film is provided, both functions, namely the moisturization of cigarettes and protection against external odors on the one hand and a certain Stiffness for the mechanical protection of cigarettes on the other hand, to take over.

The developments in the production of embossing rollers, in particular by the same applicant known, see, for example US Pat. No. 7,036,347 , have led to an ever-increasing amount of decorative effects on the inner liners and to a greater variety of advertising, which has been used not only in the cigarette industry but also in the food industry. Recently, however, efforts are underway to reduce the advertising of tobacco products greatly or eliminate altogether, so that an imprint of the innerliner with promotional designs will not be possible to the extent possible. There are therefore increasingly sought ways to create new decorative effects without the use of conspicuous imprints, gold edges or the like ornaments.

It is also looking for new ways for product identification, which has been ensured until now, especially in globally cultivated brand names. Today, so-called tactile effects are used, which are produced by special surface structures of the papers or by special engravings. Textiles such as papers are provided with inflatable IR absorption optimized colors, which produce so-called pseudo-embossings. Sense of this technique can be a noticeable relief formation, for example, to create a velvety surface or a matte effect. When used for food-safe purposes, however, wetting techniques are questionable.

In tactile surfaces, the consumer identifies the product by his sense of touch. It may also result in braille usage or hidden security features. Tactile generated Information can be read out, for example, by means of laser beams through the surface-dependent reflectivity. There are also developments today that aim to create acoustically audible effects by painting the surface.

Another area of the tobacco industry deals with the cigarette itself, for example, with the mouthpiece, also called tipping.

The increasingly restrictive legislation on smokers, as well as the desire to further features such as tactile, acoustic or other optical features on the one hand and the ever-increasing variety of packaging materials such as aluminum foil, metal-coated papers, Tippingpapiere, hybrid films, plastic films, cardboard or half board on the other cause Although conventional pin-up pin-up embossing rollers, in which both the driven roller and the counter-rollers have a large number of teeth, are still fully and successfully applicable to embossing inner liners, they reach their limits for the purposes set out above bump.

Although known roller systems with a patrone roller with Patrizenstrukturen and a matrix roller with inversely congruent Matrizenstrukturen can extend the range of decorative elements, however, are very cost-intensive and, above all, time-consuming due to the pairwise manufacturing and sorting in the production, so that their production for an industrial Embossing of, for example, metallised inner liners is not suitable for the tobacco industry.

In addition, a fine embossing can be ensured only with a very large effort in the production of such rolls. In addition, in this case, when using a patrone roller and an inversely congruent die roller, the intervening film is squeezed during embossing so as to generate tensions in the transverse direction which are unacceptable to tobacco product papers. In addition, there is a hard-to-control limit for hole formation and very high pressures are required for a high-speed on-line method, with the stamping times in the millisecond range. Finally, there is a tendency to use thicker papers.

From the foregoing, it is an object of the invention to provide a method for producing a set of embossing rollers with which it is possible to carry out embossing for the most varied described surface structures of the specified materials of various kinds in the online operation of a packaging plant. Fine embossing is understood to mean that the contours of the fine embossing structures of the rolls have a total linear error of less than +/- 10 μm and an angle error of less than 5 °. This object is achieved by the method according to claim 1.

It is a further object of the invention to keep deformations of the embossed films during embossing of regularly arranged and uniform structures transversely to the running direction so small that the rollers are operational in the online operation of a packaging installation. This object is achieved by the method according to claim 6.

Another object is to produce such a set of rolls industrially in the required precision and quantities. This object is achieved with the method according to Claim 10 solved. Other objects and advantages will be apparent from the dependent claims and the description below.

Fig. 1

zeigt schematisch einen Satz Prägewalzen des Pin Up - Pin up-Typs des Standes der Technik in einer Prägevorrichtung, wobei beide Walzen aus dem Zylinder herausragende Zähne aufweisen,

Fig. 2

zeigt schematisch einen Satz Prägewalzen des Pin Up - Pin Down - Typs des Standes der Technik, wobei die Matrizen-Walze = Pin Down Walze, invers kongruent zur Patrizen-Walze = Pin Up-Walze ausgebildet ist,

Fig. 3

zeigt schematisch einen Satz Prägewalzen des Patrizen-Matrizen-Typs gemäss Erfindung,

Fig. 4

zeigt eine Ausführungsvariante zum Satz Prägewalzen von Fig. 3,

Fig. 5

zeigt eine weitere Ausführungsvariante zum Satz Prägewalzen von Fig. 3,

Fig. 6

zeigt drei verschiedene Vergrösserungen eines Details der Patrizenwalze des Prägesatzes von Fig. 5,

Fig. 7

zeigt eine Ausführungsvariante zum Satz Prägewalzen von Fig. 5,

Fig. 8

zeigt eine weitere Ausführungsvariante zum Satz Prägewalzen von Fig. 3,

Fig. 9

zeigt eine Laseranlage zur Erzeugung von Strukturen von Patrizen-Matrizen-Walzen gemäss Erfindung,

Figuren 10-16

zeigen Ausbildungsvarianten von Strukturen auf den Prägewalzen gemäss Fig. 3,

Figuren 17-20B

zeigen schematisch Schnittzeichnungen von Ausbildungen von nicht invers kongruenten Patrizen- und Matrizenstrukturen,

Fig. 21

zeigt schematisch ein erstes Ausführungsbeispiel einer Schnellwechsel-Einrichtung für die Walzen gemäss Erfindung in perspektivischer Sicht,

Fig. 22

zeigt die zusammengebaute Einrichtung von Fig. 21 in einem Schnitt,

Fig. 23

zeigt schematisch ein zweites Ausführungsbeispiel einer Schnellwechsel-Einrichtung für die Walzen gemäss Erfindung in perspektivischer Sicht,

Fig. 24

zeigt schematisch ein drittes Ausführungsbeispiel einer Schnellwechsel-Einrichtung für die Walzen gemäss Erfindung in perspektivischer Sicht, und

Fig. 25

zeigt schematisch ein weiteres Ausführungsbeispiel einer Schnellwechsel-Einrichtung für die Walzen gemäss Erfindung in perspektivischer Sicht.

The invention will be explained in more detail below with reference to drawings of exemplary embodiments.

Fig. 1

1 schematically shows a prior art set of embossing rollers of the pin-up pin-up type in an embossing apparatus, both cylinders having protruding teeth from the cylinder;

Fig. 2

1 schematically shows a set of prior art pin up-pin down type embossing rolls wherein the die roll = pin down roll is inversely congruent with the punch roll = pin up roll,

Fig. 3

shows schematically a set of embossing rollers of the male-female type according to the invention,

Fig. 4

shows a variant of the set of embossing rolls of Fig. 3 .

Fig. 5

shows a further embodiment of the set embossing rolls of Fig. 3 .

Fig. 6

shows three different enlargements of a detail of the stamper roller of the stamping set of Fig. 5 .

Fig. 7

shows a variant of the set of embossing rolls of Fig. 5 .

Fig. 8

shows a further embodiment of the set embossing rolls of Fig. 3 .

Fig. 9

shows a laser system for producing structures of male-female rolls according to the invention,

Figures 10-16

show training variants of structures on the embossing rollers according to Fig. 3 .

Figures 17-20B

show schematically sectional drawings of embodiments of non-inversely congruent male and female structures,

Fig. 21

shows schematically a first embodiment of a quick-change device for the rollers according to the invention in a perspective view,

Fig. 22

shows the assembled device of Fig. 21 in a cut,

Fig. 23

shows schematically a second embodiment of a quick-change device for the rollers according to the invention in a perspective view,

Fig. 24

schematically shows a third embodiment of a quick-change device for the rollers according to the invention in a perspective view, and

Fig. 25

schematically shows another embodiment of a quick-change device for the rollers according to the invention in a perspective view.

Fig. 1 shows a stamping device 1 according to the prior art with a set of two rollers 2 and 3 of the type pin up - pin up. In this configuration, the steel cylinder thereof have excellent teeth 4, which are usually pyramidal and either a square or a rectangular Have base. In the cigarette packaging machines and other packaging machines such rollers of the same applicant are used for over twenty years, with the axis 5 of the driven roller 2 is fixedly mounted, while the counter-roller 3 is driven and synchronized by the driven roller. As is known, more than two embossing rollers may be arranged in such an embossing device, for. B. an embossing roller and two counter-rollers.

It is advantageous if the axis 5 of the counter roller 3 is movable in the three dimensions such that a tooth of a roller can get between four teeth of the other roller, so that a slip-free self-synchronization is possible. To make logos or authentication features, teeth of the driven roller are either completely removed or only partially, giving an image that varies with the angle of incidence and viewing angle of the viewer. In addition, it is known to mount on or on the teeth by means of micro engravings authentication features or to remove or modify certain teeth in a predetermined arrangement.

For providing authentication features or decorating inner liners, ie metal-coated paper, the pin-up-pin-up rollers are excellently suited and have proven themselves over decades. As mentioned at the beginning The requirements for precision of embossing as well as adaptations to a growing variety of packaging materials such as plastic films, hybrid films, cardboard or semi-board have increased and the more stringent regulations regarding advertising and new types of embossing which have been promised cover the limits of Pin up-pin-up embossing roll devices.

In addition to the devices with pin-up pin-up rollers, that is, with two or more Patrizenwalzen, embossments have been carried out with devices with male-female rolls or, as in Fig. 2 illustrated with so-called pin-up pin-down roller pairs.

The device 7 according to Fig. 2 has two rollers 2 and 8, wherein the Patrizenwalze 2 may be the same as in Fig. 1 while the die roller 8 is a so-called pin down roller and the recesses 9 correspond inversely congruent to the teeth 4 on roller 2. As in Fig. 1 Roller 2 is driven by the drive 6, while the roller 8 is driven by the teeth 4. In order to ensure a smooth embossing, the teeth and the recesses must be worked very precisely and coordinated with each other.

First, the patrone roller 2 is manufactured and brought together with a die steel cylinder such that the teeth of the patrone roller are imaged on the die cylinder, generally with a photoresist, wax or similar layer applied to the die cylinder. Then, the recesses 9 corresponding to the teeth 4 are machined in the die cylinder, generally by etching. However, it is also known to work out the depressions of the die roller mechanically or by means of a laser system.

Based on these two basic patterns of embossing rollers, it is known on the hard surface of a very large variety of characters, images, letters and the like, generally called 'logos', as well as security features or authentication features that are often not detected by the naked eye and by appropriate optical devices can be read, shape.

Due to the very expensive technology in the production of a Patrizen-Matrizen roller pair according to the prior art, their application for industrial purposes is very limited. In general, such systems are used for one-off or special purpose. Moreover, a conventional male-female system with inversely congruent structures has, among other things, the serious disadvantage that the film, in particular after embossing of row structures, has a distortion in the transverse direction, which makes further processing in a packaging installation very difficult. In addition, the resulting transverse stresses can lead to holes in the film, so that it is not suitable for use in the food industry and in the tobacco industry.

Based on the above description, the surface structures of the rolls, in particular the die rolls, are required in a greater variety, as well as more rationally and, more particularly, more precisely for a substantial improvement of the embossing possibilities and quality and, above all, for use in online processes can be produced. While the accuracy of the prior art could be ensured by etching or by mechanical processing with great effort, this does not apply to the rational and thus faster production of the male-die rollers in a wide variety of surface structures.

Furthermore, there is a requirement that measures be taken in order to reduce the transverse stresses in the embossed foil, which increase in ingrated congruent structures, in such a way that they are no longer disturbing for further processing.

One solution is to form the surface structures of the rolls of a set independently, i. that not first the patrone roller and physically dependent on the die roller must be formed. At present, this is for the required precision and production time preferably using a suitable laser system conceivable, which makes it possible not only Patrizenwalzen but also Matrizenwalzen rationally, accurately and above all very vielgestaltig and independently produce.

It has been recognized that the individual fabrication of male and female rolls enables a reduction in transverse strains by not matching the die structures inversely, that is, not exactly, with the associated male patterns. The fact that the dimensions and shapes of the male structures, for example teeth, do not correspond exactly to the depressions in the die roll not only improves the quality of the embossing, but also in many cases causes a sufficient reduction in the transverse stresses in the embossed film.

Especially when embossing two tipping webs on one roller each, this can lead to warping of the film web, which can come to fruition, in particular during cutting. This problem can according to Wo-2011/098376 of the same applicant, which relates exclusively to pin up - pin up rollers, thereby that the logo lines on the two Tippingbahnen are each arranged offset from each other. This means that when cutting the Tippingbahnen no tensions arise and that subsequently the Tippingbahnstücke can be easily glued around the cigarette mouthpiece to give a Tipping, where no seam is visible.

This applies to male-female rolls according to the invention not only for the embossing of relatively narrow Tippingbahnen but generally for a row-wise arrangement of embossed structures.

Fig. 3 shows a schematic representation of an embossing device 10 according to the invention with a Patrizenwalze P11 and a stencil roll M11 and an enlarged illustration of their surface structures, are shown in the rough structures GP1 and GM1 in the form of diamonds, see also the FIGS. 10 to 16 ,

Since the rough structures are not teeth, the driving force is transmitted from the punching roller P11 driven by the belt drive 6 to the die roller M11 via gears 39 and 40.

In the embodiment of Fig. 4 Rolls P11E and M11E have a rough structure GPE and GME consisting of the capital letter "E".

In the embodiment of Fig. 5 the rollers P11W and M11W have the same rough structure GPE and GME, which consists of the capital letter "E" and a coat of arms W. This coat of arms W on the patrone roller P11W is in Fig. 6 presented in different views, in Fig. 6A from the top, in Fig. 6B in perspective and in Fig. 6C on average.

Fig. 7 shows a variant of the roller pair of Fig. 5 in which the two rollers P11B and M11B have, in addition to the patterns "E" and the arms W, positioning marks 27 and 28 in order to be able to synchronize the rollers and the embossing material by means of a camera.

Fig. 8 shows a pair of embossing rollers P11L and M11L, which have no structures except for the coat of arms and are also provided with the markings 27 and 28.

In Fig. 9 is an exemplary laser system shown schematically, which makes it possible in the Fig. 10 - 16 To produce coarse and fine structures shown, which are suitable for a continuous fine engraving = macrostructuring. Therein a laser device L12 is shown with a laser 12 connected to a control circuit 13 which controls the laser 12 and a deflection unit 14 which may include beam splitters as well as acousto-optic or electro-optic modulators or polygon mirrors. The deflection unit 14, the focusing optics 15 and the deflection mirror 16 form the engraving unit 17, which can be displaced linearly in the X-axis, as symbolically indicated by the X-arrow. But it can also be provided to move the entire laser device L1 in the X-axis.

The control circuit 13 is connected to a position sensor 18 to receive and utilize the data of the rotating workpiece 22, here an embossing roll blank. The workpiece is driven by a drive 23, which is symbolized by the rotation angle φ. By combining the linear displacement of the engraving unit and rotation of the roller creates a constant helix SL which allows a uniform machining.

The use of a deflection unit, which may include, for example, one or more beam splitters and electro-optic or acousto-optic modulators or one or more polygon mirrors, enables the splitting of the original laser beam into two or more laser beams impinging simultaneously on two or more tracks SL, but have such a distance from each other that they do not disturb each other. In addition, the time interval between the impact of the individual pulses can be chosen so large that a thermal overload does not occur.

By using short pulse lasers with laser pulses of between 10 femtoseconds and 100 picoseconds, the energy is applied in a very short period of time, allowing for so-called "cold ablation" where the material vaporizes rapidly without unacceptable heating of the adjacent material becomes. The undesirable liquid state of the material, which produces crater edges and splashes, can be virtually completely avoided. The desired structures are created on a computer that controls the laser system so that it does not matter if a surface structure is created for a punch roll or a die roll. For the rollers, or their surface, for example, a suitable steel, carbide or ceramic is used.

In the Fig. 10 - 16 From the very large variety of possible surface structures, a small number of different structures are shown. Therein, the coarse structure GP1 and GM1 are the same as in FIG Fig. 3 as the superimposed fine structures change. The rhombuses 21 shown in the rough structures have male lands 22P and female grooves 22M. Exemplary dimensions are a longitudinal diagonal from 4 to 6 mm, in particular 4.6 mm and a transverse diagonal of 1.5 mm to 3 mm, in particular 2.0 mm, while the width of the webs and grooves 22 is about 0.2 mm. In the enlargements, the female mold is on the left and the male on the right, with the illumination shining from the lower left.

As can be seen in particular from the enlargements, the coarse structures GP1 and GM1 are each overlaid with a fine structure FP and FM, whereby these fine structures differ in their shapes. In Fig. 10 the fine structure FPQ consists of squares. The pitch of the squares, ie the repeating distance from each other, is about 0.04 mm. Like from the Fig. 17 - 20 will emerge, the patrix and matrix structures are not exactly inversely-congruent but their shapes and dimensions differ by a certain size from each other.

In Fig. 11 For example, the fine structure FPD and FMD are diamond-shaped instead of square. The dimensions are in Fig. 11 a bit bigger than in Fig. 10 , that is, the pitch of fine structuring here is 0.07 mm, but may of course be less, for example 0.05 mm or have a larger amount.

In Fig. 12 the fine structure FPRh and FMRh is rhombic. Again, the dimensions are the same as before.

In Fig. 13 is the fine structure FPR and FMR around. Again, the pitch of the fine structure can be 0.07 mm.

In Fig. 14 only the coarse structure GP1 and GM1 is shown, without fine structures. Such a structure is particularly suitable for the production of tactile structures that are not only palpable but also aesthetically pleasing have attractive appearance. This can z. B. characters in braille or acoustically usable structures are generated.

In Fig. 15 That is, it is shown that the male pattern GP1 is not superimposed with a fine pattern, while the template pattern GM1 is superimposed with a fine pattern FM (Q, D, Rh, R) which can be square, diamond, rhombus or round, as previously shown according to FIG. 5 a coat of arms or the like may have decoration.

In Fig. 16 It is shown that the male rough pattern GP1 is superimposed on a fine pattern FP (Q, D, Rh, R), while the template rough pattern GM1 has no fine pattern.

It should be noted that the embodiments shown represent only a small portion of all possible shapes, both in terms of coarse structure and fine structure. On this basis, a very large number of different structures can be created, for example, consist only of individual, a few logos or logotypes and the like, to which a fine structure can be superimposed. In addition, as already previously known, a microstructure may be overlaid to produce, for example, authentication features or other distinguishing features that are generally invisible to the naked eye.

In the Fig. 17 - 20 There are shown schematically some possibilities how the matrix structure can deviate from the patrix structure. For better illustration and illustration, the surface structures are tooth-shaped and enlarged in order to make the deviations more visible.

In order to be able to specify the desired deviations, the errors, i. the manufacturing tolerances are defined. As mentioned above, among other things, the improvements in roll manufacturing are aimed at producing more accurate and suitable fine-embossing structures, and thus the problem arises of achieving close manufacturing tolerances. Among other things, these tolerances are also influenced by the surface quality of the rolls and it is therefore advantageous to use a hard surface. These may be solid carbide rolls or metal rolls having a hard metal surface or all-ceramic rolls or metal rolls having a ceramic surface. These are all materials that are particularly suitable for fine machining by means of a laser system. In most cases, it is advantageous to provide the surface of the embossing rollers with a suitable protective layer.

For example, for an embossing roller having a length of 150 mm and a diameter of 70 mm and the intended processing by means of a laser device in the direction of rotation, an error of 2-4 microns and in the axial direction of such a +/- 2 microns sought and in the height, with a tooth height of 0.1 mm, one of 0.5 to 3 microns. At an angle of two opposite tooth flanks of e.g. 80 ° an angular error of less than 3 ° is sought. This results in a maximum linear error of +/- 5 μm for new rolls, so that the production-related deviations can be up to 10 μm.

However, since these values are strongly influenced by the measurements and the production, it is only possible to speak of a desired difference starting from a linear deviation of the male structures from the female structures of 15 μm and more and from an angle deviation of 4 ° and more.

The upper limit of the difference of the structures is set by the condition that the two rolls can work together unimpaired.

The desired difference of the respectively assigned structures on the male and on the die depends strongly on the material to be embossed. For example, the linear difference for embossing a film about 30 μm thick is about 40 μm and for embossing a semi-cardboard about 300 μm thick about 120 μm.

In the FIGS. 17-20B It is shown that it is advantageous for certain structures when the rolls are at a certain constant distance from each other. For a Pin Up - Pin Up roller system, such a constant distance is in the form of a reduction of a roller, or a smaller diameter at least over the length of the film by 0.02 to 0.2 mm, in the WO 2011/161002 A1 described by the same applicant.

In cases according to FIGS. 17-20B For example, the diameter of one of the rollers, advantageously the patrone roller, is intended to be less than the remainder of the roller over at least the length of the film by an amount greater than 0.02 mm. As a result, a more uniform embossing can be produced. In the FIGS. 17-20B is such a reduction, or smaller diameter of the Patrizenwalzen designated by an 'S'.

Instead of lowering also other spacer means may be provided, for. B. an electronic or mechanical distance control.

In Fig. 17 the die roll M 23 has a surface structure SM 23, wherein two opposite Flanks of the recesses have an angle α 23 and the Patrizenwalze P 23 has a structure SP 23, wherein two opposite edges of the teeth enclose an angle β 23 and β 23 is smaller than α 23. The angle can be an amount of 10 ° to 110 ° and have a difference of more than 4 °.

The die roll M24 in Fig. 18 has a die structure SM24 whose grooves N24 have a flat groove surface. The male part P24 has a surface structure SP24 whose teeth T24 are rounded.

The die roll M25 off Fig. 19 has the same surface texture SM24 as before, while the teeth T25 of the patrone roll P25 are flattened at the tip.

Fig. 20 shows a further embodiment, wherein the die roll M26 has a surface structure SM26, with rounded grooves N26, while the teeth T26 in the surface structure SP26 of the male roll P26 are also rounded, but have a smaller radius than the grooves N26.

Fig. 20A shows a further embodiment, wherein the die roller M27 has a surface structure SM27, here with a rounded groove N27, while the spring T27 in the surface structure SP27 of the male roll P27 is also rounded, but has a smaller radius than the groove N27.

Fig. 20B shows a further embodiment, wherein the die roll M28 has a surface structure SM28, with rounded grooves N28, while the teeth T28 in the surface structure SP28 of the male roll P28 also are rounded, but have a smaller radius than the grooves N28.

From the schematically illustrated FIGS. 17-20B It can be seen that the fact that the structures of the die rollers are not inversely congruent with the structures of the patrone rollers, that is, that the dimensions and also shapes of the structures of the patrone roller and the associated structures of the die roller are different, results in a smaller size Squeezing in the film between the two rollers, which greatly reduces or eliminates distortion of the embossed film in the transverse direction for a number of embossing types.

This has the great advantage that at the required high pressures between the rollers, a perforation of the film is avoided and the further processing is facilitated in a packaging system. This makes it possible for the first time to use such rolls analogously to the pin-up-pin-up rolls known per se and frequently used in the online process in a packaging installation. In the case of embossing of Tippings or arranged in web structures, it is advantageous to arrange the structural elements of the two web offset from each other.

The prior art male-female rolls were always made in pairs, and because the female rolls were formed in inverse congruence with the male rolls, it was imperative that each time one of the rolls be replaced, the other roll also be replaced. By the method according to the invention, which allows an individual production, it is conceivable to exchange individually both the male and the female die, which not only with respect to the different Wear behavior but also in terms of design options brings a big advantage.

Quick-change devices for the usual pin-up pin-up rollers are made of U.S. 6,665,998 by the same applicant and since then for the majority of all cigarette paper stamping machines in use worldwide. The axis of the counter roll is there in the three coordinate directions movable to allow self-synchronization of the embossing rollers.

The quick-change device 30 of FIGS. 21 and 22 The roller carrier 34 serves to fix the driver roller 36, which is driven via the drive 6 (not shown), and roller carrier 35 serves to fasten the roller die 37. According to FIGS Fig. 20 the roller carrier 34 is inserted in the receptacle 32 and roller carrier 35 in the receptacle 33. The housing 31 is closed with a cover plate 38.

In the present example, as in the examples according to the FIGS. 3 to 8 the die roll is driven by the driven male roll 36 via gears 39 and 40, respectively, located at one end of the rolls. In order to ensure the required high precision of the synchronization, the gears are very finely executed. However, other synchronization means may also be used, eg electric motors.

From the cut of Fig. 22 It can be seen that on the external drive side, left in the drawing, the roll axis 41 of the male roll 36 is rotatably supported in a needle bearing 42 in the roll carrier 34 and on the other side in a ball bearing 43. The two ends 44 and 45 of the roller carrier are held in corresponding openings 46 and 47 in the housing, or end plate. For the exact and unambiguous introduction and positioning of the roller carrier in the housing, the housing bottom has a T-shaped groove 48, which corresponds to the roller carrier base a T-shaped spring 49.

The roll axis 50 of the die roll 37 is mounted on one side, in the drawing on the left, in a wall 51 of the roll carrier 35 and on the other side in a second wall 52 of the roll carrier. The edges 53 of the cover 54 of the roller carrier are formed as springs, which can be pushed into the corresponding T-slot 55 in the housing 31. In this case, one side wall 51 fits into a corresponding opening 56 in the housing wall. The lid 57 projecting part of the side wall 52 fits into a recess 58 in the housing wall.

In the versions shown, in which the second roller is driven by gears, an adjustment of the rollers after mounting in the roll carrier is required. This happens, for example, with the help of the gears.

In the embodiment of the quick-change device 59 of FIG. 23 For example, the housing 60 does not have a closure plate but a wall 61 having a lower half-round aperture 62 and an upper approximately rectangular aperture 63. The two rollers and the roll supports are the same as before and the T-shaped groove for receiving the die roll carrier and the T-shaped Groove 48 in the housing bottom are also the same. The rear openings are similar to the front openings 62 and 63 in the drawing. Also in this embodiment, the roller carriers are uniquely and accurately fixed in the housing.

In the embodiment of Fig. 24 the quick-change device 64 includes two identical roller supports 65 and 66, both having a T-shaped spring 49, wherein the one roller support 65 in the bottom and the other roller support 66 is guided and held on the ceiling of the housing 67. The two roll carriers are secured by means of a closure plate 68 in opening 69 for receiving a roll end.

In the embodiment of Fig. 25 The quick-change device 70 includes a housing 71 with two opposite side walls 72, 73 in the two openings 74, 75 are arranged to receive the axes 76, 77 of the two embossing cylinders 36, 37 with gears 39 and 40. From this simplified scheme, it can be seen that first the roller is inserted into the housing and then the axle is inserted and fastened. It also follows from this example that a quick change is possible without a roll carrier.

Claims (23)

Method for the production of embossing rolls for a device for embossing packaging material with a set of two embossing rollers, one of which is driven, characterized in that the set of embossing rollers comprises a patrone roller having a patrix surface structure comprising structural elements and / or logo structures and a die roller a die surface structure associated with said patrice for co-embossing with said patrice and adapted to use said embossing rolls in the on-line fine embossing process, said die surface structure being independent of one generated previously or physically already existing Patrizen surface structure is produced. A method according to claim 1, characterized in that the contours of the surface structures of the rolls for the fine embossing are produced with a total error of less than +/- 15 microns and an angle error of less than 4 °. A method according to claim 1 or 2, characterized in that the surface structures of the embossing rollers are formed such that in on-line embossing of regularly arranged and uniform embossing patterns in a packaging system in the transverse direction to the running direction of the rollers no residual stresses in the packaging material are produced. Method according to one of claims 1 to 3, characterized in that the surface structures of the embossing rollers are formed such that the embossed film has a tactile detectable embossing pattern. A method according to claim 4, characterized in that the tactile detectable embossing pattern has special characters such as Braille or acoustically usable characters. Method according to one of claims 1 to 5, characterized in that the dimensions of the structural elements of the male roll on the one hand and the dimensions of the associated structural elements of the die roll on the other hand differ by a certain amount, but without affecting their cooperation. A method according to claim 6, characterized in that the desired deviations of the linear dimensions of the structural elements of the rollers from each other above 15 microns and / or the angles of the edges of the structural elements above 4 ° differ from each other. Method according to one of claims 1 to 7, characterized in that to reduce the transverse stresses in the embossed material, the logo structures of the embossing rollers are arranged and designed so that when passing a film strip between the embossing rollers on the film strip at least two sections are embossed such that the On a section embossed logo structures are arranged offset in each case in the direction of flow to the logo structures on the other section. Method according to one of claims 1 to 8, characterized in that on the male roll raised and on the die roller recessed positioning marks (27, 28) are generated, or vice versa. Method according to one of claims 1 to 9, characterized in that the surface structures of Embossing rollers are produced by means of a femto or picosecond laser system. A method according to claim 10, characterized in that on the surface of the rolls, a coarse structure and a superimposed fine structure is produced. Method according to one of claims 1 to 11, characterized in that the diameter of one of the embossing rolls at least over the length corresponding to the width of the web of the packaging material, with a smaller by an amount S diameter than the rest of the embossing roll is produced, wherein S a Value greater than 0.02 mm. Method according to one of claims 1 to 12, characterized in that the packaging material for the packaging of food and medicines is usable, or tipping paper, cigarette paper, innerliner, innerframe paper, hybrid paper, plastic films or cardboard or semi-cardboard for packaging tobacco goods is. Embossing roller set comprising a patrone roller (P11, P11B, P11E, P11L, P11W, P23-28, 36) produced by the method according to claims 1 to 13 and a die roller (M11, M11B, M11E, M11L, M11W, M23-28, 37), characterized in that the structural elements (GP1, GPB, GPE, GPL, GPW, FP-Q, D, Rh, R) on the Patrizenwalze and the associated structural elements (GM1, GMB, GME, GML, GMW, FM- Q, D, Rh, R) on the die roll are not inversely congruent by a defined amount of above 15 μm linear and 4 ° in the angular range. Embossing roll set according to claim 14, characterized in that at least the surface of the rolls made of metal, hard metal or ceramic, wherein the surface is optionally provided with a protective layer. Embossing roller set according to claim 14 or 15, characterized in that the one of the embossing rollers via synchronization means, preferably gears (39, 40), is connected to the other embossing roller. Use of an embossing roll set according to claims 14 to 16 in an embossing device, characterized in that the embossing device is installed either on-line or directly via a robot in a packaging installation. Use according to claim 17, characterized in that the rollers are arranged at a certain distance, preferably greater than 0.02 mm from each other. Use according to claim 17 or 18, characterized in that the embossing roller set in a quick-change device (30, 59, 64, 70) is arranged, which is designed such that the embossing rollers (36, 37) are individually and independently interchangeable. Use according to claim 19, characterized in that the embossing rollers (36, 37) are each rotatably supported in a roller carrier (34, 35, 65, 66) and the roller carriers are individually and independently removably mounted in a quick release housing in a unique position, wherein one end of the male roll carrier (34) is held in a needle bearing (42) and the other end is held in a ball bearing (43). Use according to claim 19 or 20, characterized in that the one roller carrier (34, 65) has at its lower part a spring (49) and the bottom of the housing (31, 60, 67) has a corresponding groove (48). Use according to claim 21, characterized in that the other roller carrier (66) at its upper part a spring (49) and in the upper part of the housing (67) has a groove (48) is arranged or the edges (53) of its upper side as a T-spring is formed and the top of the housing (60) has a T-slot. Use according to claim 20, characterized in that the quick-change device (70) has a housing (71) with two opposite walls (72, 73) each having two openings (74, 75) with fastening means around the axes (76, 77) of the Take up rollers (36, 37) and secure.

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