EP1074381A1 - Embossing device - Google Patents

Abstract

The embossing station, for embossing a fiber web (5), has a support frame (1) for a counter roller (2) and two embossing rollers (3,3'). A switch mechanism brings each embossing roller (3,3') alternately against the counter roller (2) or they are both together in contact with the counter roller. The embossing rollers (3,3') are over or under the counter roller (2), so that at least one is offset from the counter roller to one side. The embossing rollers, and the counter roller, have independent drives. The counter roller (2) has a hard or pliable smooth surface.

Description

FIELD OF THE INVENTION:

The invention relates to an embossing station for embossing of fiber webs.

The fibrous webs can consist of paper or non-woven fabric. The paper is preferably tissue paper for products such as Kitchen towels, toilet paper and handkerchiefs.

Such fiber webs are often embossed to give them optical To give structure. Another reason for embossing is the desire for soft or bulky products. About that In addition, the embossing can lead to layer adhesion between different fiber layers can be achieved.

An embossing station for embossing fiber webs includes one Chair for fastening a system of rollers. In particular, a counter roller and at least one for Counter roll parallel embossing roller provided with the Counter roller cooperates to form an embossing zone which the fiber web is guided.

STATE OF THE ART:

The fibrous webs are usually made in an embossing station coined with two rollers arranged parallel to each other. Between the rollers is the embossing zone through which the to formative fiber web is guided. At least one of the rollers the embossing station must have a structured surface, the other roller can be a smooth counter roller or also with one that matches the structure of the first roller Structure can be provided. Most rollers with structured surface have a hard surface, such as B. steel. The smooth counter roll can be both a yielding or a hard surface such as 3. rubber or steel, to have.

A problem with conventional technology is that Embossing roller of an embossing station must be replaced if a new embossing pattern is to be used. The exchange of rollers is very time-consuming and personnel-intensive. The one and Removing a roller and setting the embossing pressure as well the position of the embossing roller in relation to the counter roller take more than eight hours. It follows that production planning must be very careful, but so must becomes inflexible. Therefore it is difficult to meet the demand of the To meet the market, the more and more new ones Products.

The arrangement of two complete stamping stations with different embossing rollers in a row circumvents this Production shutdown problem when replacing or Maintenance of an embossing roller, however, is a very expensive solution to the Problem and in most cases not feasible because it is spatially impossible to complete another Embossing station in an existing production line integrate.

US 4,000,242-A describes an embossing station for paper webs with several parallel to a central counter roll arranged rollers. The counter roll is supported by the surrounding rollers, of which at least one roller one Represents embossing roller. The counter roll forms with each of the surrounding roller a stamping nip through which the to be stamped Paper web is guided. The paper web can also be on one or several embossing nips are passed. The disadvantage this arrangement is that all surrounding rollers are always in Interaction with the backing roll must be because the Mating roller is not supported otherwise. Therefore they can Rollers that are not currently used for embossing, not be replaced or serviced during operation. Another disadvantage of the stamping station according to US 4,000,242-A is that only counter rolls with yielding Surface can be used.

PRESENTATION OF THE INVENTION:

The invention has for its object an embossing station propose a change in the embossing pattern on a Production line enabled without significant loss of time.

This task is accomplished through an embossing station with the characteristics of claim 1 solved. On the chair of an embossing station are at least two embossing rollers around a counter roller arranged. The embossing rollers and the counter roller are parallel rotatable in relation to each other in the chair and absorbing force attached. The embossing rollers can also individually between an operating position and a rest position are moved. When an embossing roller is at rest, is a resting distance between the embossing roller and the counter roller, which has to be so large that the embossing process by the in embossing roller / s located in the rest position is not influenced becomes. The embossing rollers, which are not currently in use, are at rest.

The embossing rollers are fastened in the frame so that they by switching from the rest position to one Operating position can be moved so that it can be moved with the Interact with the counter roller to create an embossing pattern. This includes the embossing pressure and the position of the embossing rollers preset in the operating position in relation to the counter roller.

The fiber web to be embossed can consist of one or more There are fiber layers that are embossed at the same time. there can layer adhesion between two or more fiber layers be generated mechanically by the embossing, or by Gluing.

The other advantages are based on the embodiment described, in which the embossing station two embossing rollers includes.

The embossing station also includes a switching mechanism, alternatively, each of the embossing rollers individually or both Embossing rollers together in an operating or rest position can be brought. Are both embossing rollers with coordinated, different embossing patterns provided with this solution without much effort at least three different embossing patterns are created. To the each roller can be operated individually; to the others can operate both at the same time Embossing roller patterns are created that result from overlay the embossing pattern of both individual rollers results. With the proposed solution can be without significant interruption another pattern is set and produced during production become. In addition, this solution has the advantage that any maintenance work on one of the two embossing rollers can be run while the other roller is operating is.

For switching between the individual embossing rollers furthermore, no special technical staff is required, but this one Process can be taken over by the machine operator. Thereby can react very flexibly to product requirements, and an increase in the readiness to deliver occurs. This leads to an increase in productivity at the same time.

Advantageous embodiments are due to the rest Claims marked.

According to an advantageous embodiment, the embossing rollers are arranged above the counter roll, at least one of the Embossing rollers are laterally offset from the counter roller. This results in a "V" or "L" arrangement. Thereby a space-saving solution can be achieved. The Embossing rollers can be arranged in this arrangement due to better access can be exchanged and serviced more easily. This also offers Arrangement pollution advantages. It is with relatively little downtime due to cleaning work to count. If the embossing rollers are arranged above the Counter roll can also the own weight of the embossing rollers Printing can also be used.

According to another advantageous embodiment, the Embossing rollers arranged below the counter roller, wherein again at least one of the embossing rollers laterally offset is arranged to the counter roller. This so-called "A" arrangement is less in terms of access to the embossing rollers favorable than the "V" arrangement described above however, the advantage of being the focus of the embossing station is lower. This creates the risk of occurrence of Vibrations of the stool decreased, and the Stability requirements for the chair can be reduced become.

The embossing rollers preferably have separate ones Printing. This allows you to choose one or the other Embossing roller are pressed against the counter roller. Furthermore, the Printing can be adapted to the embossing pattern. Moreover are in a combination embossing in which both embossing rollers are in use compared to single roll embossing different pressures necessary. These pressures are also depending on the dot pattern of the different rollers. In the Embossing multilayer fiber products offers a separate one Printing continues to have the advantage of being higher Printing of the second stamp compared to the first stamp greater layer adhesion between the individual fiber layers is produced. The pressure of the second embossing decreases chosen as that of the first imprint, this has an effect hardly on the layer liability of the existing embossing.

When switching between one and the other Embossing roller or when changing the embossing roller can also time saved by separate printing, that the printing doesn't have to be transferred.

According to a preferred embodiment, the Printing in the radial direction. This will Avoided difficulties of non-radial printing, where the embossing u. U. one-sided in Production flow direction is warped.

The embossing rollers advantageously have separate ones Drives. The separate drive is predominantly with the combined use of the two embossing rollers required. Due to the lengthening of the tissue web, it is advantageous if the drive of the in the production flow of the second embossing roller runs a little faster than the first one. This will avoid crushing or sagging of the web. Furthermore, an offset of the embossing pattern of the two rollers can be achieved, which is the realization of one fourth, slightly modified embossing pattern. Finally, the use of two separate drives makes it easier compliance with the report. By an exact Repeatability becomes a blurring of the embossing points avoided.

According to a preferred embodiment, the embossing rollers driven by servo motors. This can make a very easy setting of the embossing register of the two rollers be made possible. Current controls also allow servomotors have a resolution of at least 32,000 Steps at 360 °, so that with a 4-use embossing roller an accuracy of up to 6/1000 mm can be achieved.

A 4-use embossing roller is an embossing roller with one repeating patterns, e.g. for handkerchiefs or Napkins, the pattern four times around the circumference of the Roller repeated. Of course, 2-, 3-, 5- etc. useful rollers can be used.

According to a preferred embodiment, the Embossing station one or more pulleys. With the help of The tissue web can be deflected on the smooth counter roller looping around. This enables the To keep the length of the embossing constant and the distance traveled regardless of the intervention of one or two To design embossing rollers. A change in the embossing pattern, So switching from one to the other or to two embossing rollers, therefore does not require a new one Cross-section adjustment. The installation of Deflection pulleys when determining the levels for entry and exit Outlet from the embossing unit.

The deflection rollers can guide the paper web so that subsequent rolling or folding devices cannot be adjusted have to.

Finally, the deflection rollers can be arranged in such a way that the embossing is on the top or bottom of the web. At a predetermined packaging process within the Production line can thus design the embossing pattern be that it is cheap in the design considerations Packaging lies.

According to a preferred embodiment, the diameters are the embossing points of the one roller are chosen somewhat smaller than that Diameter of the embossing points of the other embossing roller. At The use of two embossing rollers at the same time can the smaller point is placed in the larger point, where there is some scope for repeatability. This increases the flexibility of the design.

The stamping station advantageously comprises a device for radial adjustment of the embossing rollers. This device is designed so that the distance between the embossing rollers is opposite the counter roller is preset so that a predetermined one Roller center distance between the embossing roller and the counter roller is observed. As a result, when switching from one time-consuming adjustment to the other embossing roller largely avoided.

The distance between the embossing rollers and the counter roller is preferred in the rest position larger than the thickness of the embossed Fiber web. This allows the fiber web to pass through the Space between the embossing roller and the counter roller be guided when the respective embossing roller is just in Rest position is located without the embossing pattern that through the other embossing roller was produced is influenced.

Preferably, the counter roll has a hard, smooth one Surface. This surface can consist of steel. This creates an embossing zone between the counter roller and the embossing roller, the embossing gap being narrower than that Cloth thickness of the fiber web to be embossed.

In another preferred embodiment, the Mating roller a compliant smooth surface. This The surface can be made of rubber, for example. In this case the rollers lie against each other and a stamping nip is created.

The counter roll advantageously has its own Drive system. Compared to the solution where the counter roller is passively moved by the rotation of the embossing roller this has the advantage that especially when the fibrous web wraps around a larger part of the counter roll, about 20% of the Perimeter or more the risk of tearing the tissue web is reduced. This is mainly achieved by the fact that the speed of the counter roll to the speed of the Embossing rollers is adjusted.

BRIEF DESCRIPTION OF THE DRAWINGS:

Fig. 1

eine schematische Ansicht einer bevorzugten Ausführungsform der Erfindung;

Fig. 2

eine schematische Ansicht der bevorzugten Ausführungsform der Erfindung aus Fig. 1 mit der zweiten Prägewalze im Eingriff, wobei die Oberseite der Faserbahn geprägt wird;

Fig. 3

eine schematische Ansicht der bevorzugten Ausführungsform der Erfindung aus Fig. 1 mit der ersten Prägewalze im Eingriff, wobei die Oberseite der Faserbahn geprägt wird;

Fig. 4

eine schematische Ansicht der bevorzugten Ausführungsform der Erfindung aus Fig. 1 mit der zweiten Prägewalze im Eingriff, wobei die Unterseite der Faserbahn geprägt wird;

Fig. 5

eine schematische Ansicht der bevorzugten Ausführungsform der Erfindung aus Fig. 1 mit der ersten Prägewalze im Eingriff, wobei die Unterseite der Faserbahn geprägt wird;

Fig. 6

eine schematische Ansicht der bevorzugten Ausführungsform der Erfindung aus Fig. 1 mit zwei Prägewalzen im Eingriff, wobei die Oberseite der Faserbahn geprägt wird;

Fig. 7

eine schematische Ansicht der bevorzugten Ausführungsform der Erfindung aus Fig. 1 mit zwei Prägewalzen im Eingriff, wobei die Unterseite der Faserbahn geprägt wird;

Fig. 8

eine schematische Ansicht einer weiteren Ausführungsform der Erfindung;

Fig. 9

eine schematische Ansicht einer weiteren Ausführungsform der Erfindung;

Fig. 10

eine schematische Ansicht der Ausführungsform der Erfindung aus Fig. 9 mit der ersten Prägewalze im Eingriff, wobei die Oberseite der Faserbahn geprägt wird;

Fig. 11

eine schematische Ansicht der Ausführungsform der Erfindung aus Fig. 9 mit zwei Prägewalzen im Eingriff, wobei die Unterseite der Faserbahn geprägt wird;

Fig. 12

eine schematische Ansicht einer weiteren Ausführungsform der Erfindung;

Fig. 13

ein Beispiel für ein Prägemuster einer Prägewalze;

Fig. 14

ein weiteres Beispiel für ein Prägemuster einer Prägewalze; und

Fig. 15

ein Beispiel für ein Prägemuster, das durch Überlagerung der Prägemuster aus Fig. 13 und 14 entsteht.

The invention is explained below purely by way of example with reference to the attached figures. Show it:

Fig. 1

a schematic view of a preferred embodiment of the invention;

Fig. 2

a schematic view of the preferred embodiment of the invention of Figure 1 in engagement with the second embossing roller, wherein the top of the fiber web is embossed.

Fig. 3

a schematic view of the preferred embodiment of the invention of Figure 1 in engagement with the first embossing roller, wherein the top of the fiber web is embossed.

Fig. 4

a schematic view of the preferred embodiment of the invention of Figure 1 in engagement with the second embossing roller, wherein the underside of the fiber web is embossed.

Fig. 5

a schematic view of the preferred embodiment of the invention of Figure 1 in engagement with the first embossing roller, wherein the underside of the fiber web is embossed.

Fig. 6

is a schematic view of the preferred embodiment of the invention of Figure 1 with two embossing rollers in engagement, wherein the top of the fiber web is embossed.

Fig. 7

a schematic view of the preferred embodiment of the invention of Figure 1 with two embossing rollers in engagement, wherein the underside of the fiber web is embossed.

Fig. 8

is a schematic view of another embodiment of the invention;

Fig. 9

is a schematic view of another embodiment of the invention;

Fig. 10

is a schematic view of the embodiment of the invention of Figure 9 in engagement with the first embossing roller, wherein the top of the fiber web is embossed.

Fig. 11

is a schematic view of the embodiment of the invention of Figure 9 with two embossing rollers in engagement, wherein the underside of the fiber web is embossed.

Fig. 12

is a schematic view of another embodiment of the invention;

Fig. 13

an example of an embossing pattern of an embossing roller;

Fig. 14

another example of an embossing pattern of an embossing roller; and

Fig. 15

an example of an embossing pattern which is produced by superimposing the embossing pattern from FIGS. 13 and 14.

1 is an embossing station 10 according to the invention shown. The embossing station consists of a chair 1, in which a smooth counter roll 2 and a first and second Embossing roller 3, 3 ', each with a central axis parallel, rotatable and force-absorbing. The embossing rollers are arranged in a V-shape at an angle above the counter roller. The Embossing rollers can be between an external rest position and an inner operating position. If there is one Embossing roller is in the operating position, a forms Embossing zone between the embossing roller and the counter roller. By this embossing zone guides the fiber web 5 to be embossed. If an embossing roller is in the rest position, the Idle distance between the embossing roller and the counter roller be large that the one in the rest position Embossing roller does not affect the embossing process. Preferably the resting distance should be greater than the thickness of the to be embossed Be fiber web.

The surface of the counter roller can be smooth. The surface the backing roll can have a resilient rubber surface or also a hard surface consisting of e.g. B. made of steel, to have.

In the case where the surface of the backing roll gives way is an embossing roller located in the operating position pressed against the counter roll, the embossing zone Embossing nip is. In the event that the surface of the counter roll is hard, the embossing zone consists of an embossing gap between the counter roller and the embossing roller, this embossing nip is narrower than the fiber web to be embossed.

In the embodiment shown in FIG. 1, a used embossing roller radially against the counter roller with a certain embossing pressure pressed. The embossing rollers are with a (not shown) pressure arrangement against the Counter roll pressed. This printing arrangement can be used together for the two embossing rollers, although a separate one Printing arrangement for each embossing roller is preferred. This is therefore important because each embossing roller has a different embossing pressure may require, and because you then with two embossing rollers can shape at the same time. You can also switch between the two embossing rollers can be made faster if the Printing arrangement not laid from one embossing roller to another must become.

The embossing station also includes a (not shown) drive for the rotation of the embossing rollers. This rotary drive can also be used jointly for the two embossing rollers, although here too a separate one Rotary drive is preferred for each embossing roller. If each embossing roller has its own drive, everyone can The embossing roller can be controlled separately, and the two rollers can be used simultaneously. That increases the The flexibility of the embossing station is considerable. As Rotary drives can be used with all conventional drive systems are used, for example servomotors.

The counter roll can be passive due to the rotation of the embossing rolls carried along and thereby set in rotation. This Solution works satisfactorily when the fibrous web only briefly, in the embossing zone, in contact with the counter roller is coming. If the fiber web is a larger part of the counter roll wraps around, more than 20% of the circumference, is that There is a great risk that the web will tear off. To avoid such The counter roller can also be torn off on a rotary drive be connected. The speed of the counter roller can can be adapted to the speed of the embossing rollers.

The embossing station shown in Fig. 1 also has two Deflection rollers 4, 4 ', the fiber web through the embossing station 10 in and out. A professional can determine the position of this Change pulleys to the web guidance one Adapt production line in which the stamping station is installed.

2 to 5 each show the embossing station from FIG. 1 one of the rollers in the operating position and the other Embossing roller in the rest position.

2 and 3, the fiber web is so over the pulleys passed through the embossing station that the top of the Fiber web is directed against the embossing roller.

4 and 5, however, is the underside of the fiber web directed against the embossing roller.

The second embossing roller is located in FIGS. 2 and 4 3 '; and in Figs. 3 and 5 there is the first one Embossing roller 3 in the operating position.

6 and 7 also show the embossing station from FIG. 1, where both embossing rollers are in the operating position.

In Fig. 6 the top of the fibrous web is against the Embossing roller pressed and in Fig. 7 the underside of the fiber web embossed.

8 shows a further advantageous embodiment of the Arrangement of the embossing rollers. Here the embossing rollers are A-shaped arranged obliquely under the counter roller. The A-shaped Configuration of the embossing rollers has the advantage that the Focus is low. The disadvantage is that the Accessibility of the embossing rollers is worse than that of the V-shaped one Arrangement of the embossing rollers. Furthermore, the weight the embossing rollers are not part of the embossing pressure against the Counter roller can be used. The printing takes place as for 1 also radially. Incidentally, has the stamping station with the A-shaped arrangement of the rollers same features as for the V-shaped arrangement of the Rolling the embossing station of Fig. 1 is described. The Fibrous web can be made in a similar manner as in FIGS. 1 to 5 is shown.

9 shows a further embodiment of the invention. Here is the first embossing roller over and a second embossing roller arranged next to the counter roller. The roller configuration is so L-shaped. This configuration is not so space-saving like the one described above and has no other features on.

Also in the embossing station with the L-shaped arrangement of the The embossing rollers can be rolled individually or simultaneously be used.

Fig. 10 shows the embossing station in operation with one of the two rollers, Fig. 11 with both rollers. Of course the track can also be run in another way, too by deflecting rollers, not shown. 10 is the Top of the fiber web against the one in operation first embossing roller 3 directed and in Fig. 11 is the Underside of the fiber web against the one in operation first and second embossing roller 3, 3 'directed.

12 shows a further embodiment of the invention with two embossing rollers 3, 3 ', which are inclined under the counter roller are arranged. In contrast to the A and V-shaped configurations is in the Tandem configuration of the embossing pressure is not applied radially. The printing can be done more easily here than with the A and V configuration, however, there is a risk that the embossing is warped on one side in the direction of product flow.

13 and 14 each show achieved with an embossing roller Embossing pattern. Such an embossed pattern corresponds to the state that only one of the two embossing rollers is in use located.

In Fig. 15 an embossing pattern is shown, which by The embossing pattern from FIGS. 13 and 14 is superimposed. This embossing pattern can be made in accordance with the present invention are generated simply by the fact that both embossing rollers are in use at the same time.

Claims (12)

Embossing station for embossing fiber webs, comprising a frame, a counter roller, and at least two embossing rollers,
characterized in that
the embossing station further comprises a switching mechanism which is designed such that, alternatively, each of the embossing rollers individually engages with the counter roller or a plurality of embossing rollers together with the counter roller. Embossing station according to claim 1,
characterized in that
the embossing rollers are arranged above the counter roller, at least one of the embossing rollers being arranged laterally offset from the counter roller. Embossing station according to claim 1,
characterized in that
the embossing rollers are arranged under the counter roller, at least one of the embossing rollers being arranged laterally offset from the counter roller. Embossing station according to one or more of the preceding claims,
characterized in that
the embossing rollers have separate printings. Embossing station according to one or more of the preceding claims,
characterized in that
the pressure is given radially. Embossing station according to one or more of the preceding claims,
characterized in that
the embossing rollers are driven by separate drives. Embossing station according to one or more of the preceding claims,
characterized in that
the diameter of the embossing points of at least one embossing roller is smaller than the diameter of the embossing points of the other embossing roller. Embossing station according to one or more of the preceding claims,
characterized in that
the embossing station comprises a device for adjusting the embossing rollers, the distance of the embossing rollers from the counter-roller in the operating position being preset such that a predetermined roller center distance between the embossing roller and the counter-roller is maintained. Embossing station according to one or more of the preceding claims,
characterized in that
a rest distance of the embossing rollers to the counter roller in the rest position is greater than the thickness of the fiber web to be embossed. Embossing station according to one or more of the preceding claims,
characterized in that
the counter roller has a hard, smooth surface. Embossing station according to one or more of claims 1 to 10,
characterized in that
the counter roll has a compliant, smooth surface. Embossing station according to one or more of the preceding claims,
characterized,
that the counter roll has a drive.

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