DE102006043288A1 - Material e.g. tissue, web embossing device, has pre-tensioning device producing pre-tensioning force and bearing seats that are held spaced to each other by forming embossing gap by pre-tensioning device - Google Patents

Abstract

The device has two embossing rollers that are supported in pivot bearings (3) by bearing pins (11, 21) on both sides of roller barrels (10, 20). An axial distance between the bearings is changed by an adjusting unit (4) such that an embossing gap between the rollers and barrels is adjusted in thin width. An adjustment device (5) has pivot bearings (50, 51) arranged on the rollers. Bearing seats are arranged between the bearings (50, 51). A pre-tensioning device produces pre-tensioning force, where the seats are held spaced to each other by forming the gap by the pre-tensioning device.

Description

The The invention relates to a device for embossing a material web, comprising two with an embossed print loadable embossing rollers with roll bales, between which an embossing gap for the passage of the material web is formed, wherein the embossing rollers each on both sides of the roll barrel by means of axial bearing pin in Rotary bearings of the device are mounted and adjusting means are provided, by means of which the axial distance between the pivot bearings of the embossing rollers variable is, so the embossing gap the same is adjustable in its clearance.

at embossing systems for embossing a material web that must work with an embossing gap, be Adjustment required for adjusting the embossing gap. such embossing systems usually consist of a steel roller pair, i. the embossing roll and also the other counter-roll embossing roll are made of steel.

• a) das Prägen mit Unionwalzen, bei denen das zu prägende Material zwischen einer positiv und einer negativ gravierten Prägewalze, die genau zueinander eingestellt sind, verformt wird;
• b) das Prägen mit Zwillingswalzen, wobei die zu prägende Materialbahn zwischen zwei positiv gravierten Walzen, deren Gravuren sowohl aufeinander als auch ineinander eingestellt werden können, geprägt wird;
• c) das Prägen „Punkt auf Punkt", wobei ebenfalls zwei positiv gravierte Prägewalzen verwendet werden und so eingestellt werden, dass die jeweils positiv gravierten Elemente zueinander stehen, so dass die zu prägende Materialbahn zwischen den positiv zueinander stehenden Punkten geprägt wird;
• d) das Prägen „Punkt gegen Fläche", wobei eine Prägewalze positiv graviert und die entsprechende als Gegenwalze dienende zweite Prägewalze glatt ausgebildet ist und die zu prägende Materialbahn einseitig mit der positiv gravierten Prägewalze gegen die glatte Prägewalze geprägt wird.

Various designs of embossing rollers are known from the prior art, which can be roughly divided into four main groups:

• a) embossing with Union rollers, in which the material to be embossed between a positive and a negative engraved embossing roller, which are set exactly to each other, is deformed;
• b) the embossing with twin rolls, wherein the material web to be embossed between two positively engraved rolls whose engravings can be set both on each other and into each other, is embossed;
• c) the embossing "point to point", whereby also two positively engraved embossing rollers are used and adjusted so that the respectively positively engraved elements are mutually aligned, so that the material web to be embossed is embossed between the positive points to each other;
• d) the embossing "point against surface", wherein an embossing roller positively engraved and the corresponding serving as a counter roller second embossing roller is smooth and the web to be embossed is embossed on one side with the positively engraved embossing roller against the smooth embossing roller.

All these aforementioned systems require one Adjustability of the embossing gap, to be able to adjust this to the material to be processed or if necessary due to wear or material change the embossing gap be able to adjust.

The explained below Invention is basically Applicable to all the above-mentioned main groups of stamping types.

Usually become the embossing rollers by means designed as a spherical roller bearings pivot bearings and bearing stones in a so-called roll chair or cassette within the Device guided to each other.

For the embossing operation it is necessary that the embossing rollers axially, some are also aligned radially exactly to each other. This gets through the jewels in conjunction with the roller or cassette of the device as well as partially via a radial adjustment via gears, the are mounted on the journals reached. In addition, the so-called embossing gap between the roll bales of the embossing rolls be set, i. the embossing rollers are set at a precisely defined distance from each other. This distance is necessary so that the material web to be embossed is not overprinted, reached the exact embossing height and the embossing rollers not by accidental contact wear out prematurely.

A known adjusting device for adjusting the embossing gap is based on a riving knife adjustment with a more or less far in a gap retractable wedge, another known adjustment has a fixed threaded bolt and a so-called Spaltinstellmutter. These two aforementioned adjusting devices are always between the bearing housings the rollers arranged.

However, such known adjusting devices have the significant disadvantage that the necessary clearance of the spherical roller bearings used for example for the storage of the embossing rollers and all other storage games lead to a residual clearance of storage of at least 0.05 to 0.1 mm. This rest game then leads in embossing operation, in which the embossing rollers are acted upon with a predefined embossing, to the fact that the embossing rollers move each other unintentionally and uncontrollably, whereby the clear width of the embossing gap is always changed. These movements are the more pronounced, the greater different load changes occur within an embossing system, as is the case for example in so-called format embossing rollers, which are used for example for embossing tissues or napkins. Here, several layers of tissue material are embossed together so that the individual layers stick together. The embossing rollers used for these products usually have between 2 and 20 formats per roller, ie with an eg 16-format embossing roller there are 5 engraved strips in the longitudinal direction, ie around the embossing roller, and 16 engraved strips in the transverse direction. With each embossing of the layers with a transversely extending engraved strip, the printing surface increases in the embossing operation to a multiple of the pressure surface of the engraving strips in the longitudinal direction, depending on of arrangement, number and size of formats. Due to this extreme, constantly changing compressive force, the embossing rollers are set in vibration within the remaining bearing clearance, ie the embossing rollers undesirably deviate from each crossbar. Therefore, in order to keep this evasion within reasonable limits, it is necessary to set the embossing pressure higher than necessary for embossing the engraving strips in the longitudinal direction, but this increases wear and deteriorates the embossing result.

From the DE 297 16 031 U1 Furthermore, an adjusting device for a pair of rollers for adjusting a nip is known, which eliminates the clearance clearance by spaced arrangement of the adjustment of the pivot bearings of the embossing rollers insofar as it generates a counter-pressure to be applied embossing pressure, the opposite storage air in a non-interfering region opposite to acting Embossing pressure shifts. However, the known device is structurally complex and expensive and can be used only on specially designed devices.

task The present invention is therefore an apparatus of the above to further develop such a way that the necessary existing bearing air in the pivot bearings of the embossing roller as a disturbing element across from a uniform embossing operation is turned off, this device is simple and inexpensive should be produced and not only to redesigns, but also as retrofit solution for already existing embossing devices is feasible.

to solution the task is inventively proposed that at least a compensation device is provided with two pivot bearings, from which a first pivot bearing on the journal of the first embossing roll and a second pivot bearing on the journal of the second embossing roll is arranged and between two pivot bearings of the balancing device Bearing shells are arranged, which the respective adjacent pivot bearing at least record area and a biasing device for generating a biasing force is provided by means of which the bearing shells with the formation of a biasing gap spaced apart halterbar are.

The provided with such a compensation device device solve the Initially described problems with respect to unwanted vibrations and overprinting the Longitudinal engraving on easy way.

Become the embossing rollers collapsed by applying the preset embossing pressure, must first overcome the applied biasing force of the biasing device be before the embossing built or the desired Column setting for the embossing gap pending. This counterpressure of the pretensioner causes the embossing rollers against the direction of the embossing pressure move outward within the bearing clearance, allowing the bearing clearance is canceled in the printing direction. By the compensation device according to the invention Thus, each set of rollers consisting of two embossing rollers with usual Adjustment, such as splitting wedge or Spaltinstellmutter operated without play be without the necessary La gerspiel to unwanted disorders e.g. by avoiding the embossing rollers at the load changes leads.

at the device according to the invention is not just the embossing the embossing rollers adjustable, but also the opposite biasing force the balancing device is by selecting appropriate biasing devices adjustable as desired according to the respective requirements.

advantageous Embodiments and developments of the invention are the subject the dependent Claims.

According to one Proposal of the invention comprises the biasing device at least a compression spring, which is arranged between the bearing shells, and at least one lag screw for biasing the at least one Compression spring between both bearing shells.

The Compression spring can in this case preferably in a bore of a bearing shell be arranged so that the compensation device sufficient inherent stability receives.

Farther it is preferred that a piston is provided which is connected to the compression spring fitting is inserted into a receiving bore of the bearing shell, wherein the piston is more preferably in the bore of the opposite Bearing shell, which also receives the compression spring, introduced and is sealed by a sealing ring against the bearing shell, so that even in continuous operation of such a device no Pollution can reach the area of the compression springs.

to Creating a particularly compact compensation device is the Tightening screw preferably arranged coaxially to the compression spring and the piston.

Preferably, each compensating device comprises two lag screws with compression springs and pistons which, viewed in the axial direction of the embossing roller, are arranged symmetrically on both sides of the longitudinal axis of the embossing roller. Of course it is in Frame of the invention also possible, instead of two compression springs and a higher number of compression springs to provide about four or six compression springs per compensation device, especially when higher biasing forces are required.

in the Within the scope of the invention Compression springs with linear or progressive spring characteristic used be, where it is further preferred in the compression springs, for example can act coil springs or disc spring packages. The latter have the advantage that due to the friction of the individual Disk spring assemblies to each other the system will be given a certain amount of self-damping may be what causes the generation of vibrations within the equalizer counteracts.

Around a lateral displacement of the pivot bearing of the balancing device To prevent, preferably, each bearing shell is one-sided with a Waistband to the side guide of the pivot bearing received therein, i. on the warehouse side the federal government is trained as a floating camp.

The Pivot bearings of the compensation device itself are in a known manner placed on corresponding cylindrical paragraphs of the bearing pin and attached by means of retaining rings.

A Another preferred embodiment provides that the compensation device arranged between the roll barrel and the rotating rollers of the embossing roller is so that they can be integrated as a compact unit in the device is and can be retrofitted in existing devices.

The Rotary bearings of the compensation device are preferably as deep groove ball bearings trained, however, the invention is not on such bearings limited.

Further Preferably, on both sides of the roll bales each have a compensating device provided to distribute the forces occurring symmetrically and to equally eliminate the bearing clearance on both sides of the embossing rollers.

One Method of embossing a material web using a device explained above is the subject of claim 14 and characterized thereby from that the pretensioner in the loaded state of the embossing rollers in the bias is biased that the bias gap greater than the adjustment of the embossing rollers when applying the embossing pressure is, so that between the bearing shells upon application of the embossing rollers with the embossing print a tempering gap remains, for a particularly smooth run the device provides.

It be mentioned, however, that it is also conceivable to pretension the pretensioning device in such a way that that when applying the embossing pressure the two bearing shells come into contact with each other.

In the previously explained However, it is preferred, even with applied embossing still a biasing gap within the compensating device according to the invention holding, for example, 1 to 2 mm between the bearings can amount.

For example can be provided, the two cups in unloaded condition with a biasing gap of about 5 to 6 mm apart to arrange and then by pressing the lag screws to reduce this gap by about 1 mm, so that starting from a prestressing gap with 6 mm in unloaded condition remain in pretensioned state about 5 mm bias gap. If so, which is usual is, the embossing rollers when applying the embossing pressure about 4 mm are moved toward each other, so remains when applied embossing still a preload gap between the two cups of at least 1 mm.

Further Embodiments and details of the device according to the invention will be described below with reference to an embodiment Drawing closer explained. Show it:

1 in a schematic representation of the structure of a device according to the invention,

2 the balance of the bearing clearance achieved by using the device according to the invention in a schematic representation,

3 the side view of a compensating device according to the invention,

4a and 4b the upper bearing shell of the compensating device according to the invention from two different angles,

5a and 5b the lower bearing shell of the balancing device according to the invention from two different angles,

6 schematically the structure of embossing rollers used in the invention.

From the 1 is an apparatus for embossing a material web, not shown, which can be acted upon as essential components two embossed with an embossing embossing rollers 1 . 2 with roll bales 10 . 20 includes, between which one from the 6 apparent embossing gap P is formed, so that a material web, for example meh rere layers of tissue material can be pulled through the embossing gap P.

For this purpose, the embossing rollers 1 . 2 with its both sides in the axial direction projecting journal 11 . 21 in pivot bearings 3 stored, being between the pivot bearings 3 an adjusting device 4 in the form of a fixed spindle 40 with rotatable adjusting nut 41 is provided so that by operating the adjusting nut 41 the axial distance between the pivot bearings 3 the embossing rollers 1 . 2 is variable and as a result, the embossing gap P between the roll barrel 10 . 20 the embossing rollers 1 . 2 in its clearance is adjustable.

Problematic in such embossing systems with embossing rollers 1 . 2 It is that these, for example, in training as a format embossing rollers in one of the 6 apparent configuration both engraving strips 100 have, which extend in the longitudinal direction, ie around the embossing roll, as well as engraved strips 101 in the transverse direction. If now the engraving strips 101 acting in the transverse direction on the drawn through the embossing gap P material web, the back pressure increases significantly due to the sudden increase in embossing area against the back pressure, the engagement of the engraved strips 100 in the longitudinal direction.

In the previous systems for storing the embossing rollers 1 . 2 this causes the embossing rollers 1 . 2 at each load change, ie change from low to high embossing pressure and back to low embossing pressure due to the engagement of the engraved strips 101 in the transverse direction in the context of necessarily within the pivot bearing 3 existing bearing games in the opposite direction to the embossing dodge, but this significantly worsens the embossing result.

To counteract this phenomenon, the device shown on both sides in the area between the roll barrel 10 . 20 the embossing rollers 1 . 2 and the respective pivot bearings 3 one each with reference number 5 characterized balancing device, which in more detail from the 3 is apparent.

The balancing device 5 initially comprises two, for example, designed as a deep groove ball bearing pivot bearing 50 . 51 , where the pivot bearing 50 on a cylindrical section 12 the journal of the embossing roll 1 and accordingly the pivot bearing 51 on a cylindrical section 22 the journal of the embossing roll 2 mounted and there by means of a retaining ring 13 . 23 is secured in a conventional manner.

Between both pivot bearings 50 . 51 has the equalizer 5 two in more detail also from the 4a . 4b . 5a . 5b apparent bearing shells 53 . 54 on, each one receiving area 535 . 545 have, so that they a portion of the outer periphery of the respective adjacent pivot bearing 50 . 51 be able to record. As a result, lie the two pivot bearings 50 . 51 each with a portion of its outer circumference form-fit in the two bearing shells 53 . 54 , The recording area 535 . 545 the bearing shells 53 . 54 accordingly has a radius of the male pivot bearing 50 . 51 adapted radius and is formed on one side as a floating bearing. On the opposite side is a radial collar 533 . 543 provided, the lateral guidance of the recorded pivot bearing 50 . 51 causes.

The details of the 4a and 4b apparent bearing shell 53 for receiving the pivot bearing 50 also indicates on both sides of the recording 535 for the pivot bearing 50 a continuous cylindrical bore 531 on, which towards the top stepped to a recording 530 for the head of one out 3 apparent tension screw 55 and towards the bottom stepped to a recording 532 for one out 3 apparent piston 56 extended.

On the other hand, in more detail from the 5a and 5b apparent lower bearing shell 54 for receiving the pivot bearing 51 on both sides of the bearing receiver 545 provided with a stepped through hole, the bottom towards a threaded portion 540 in which the lag screws 55 can be screwed, above the threaded portion 540 with a recording room 541 for one out 3 apparent pressure spring 57 and is also to the top with a recording 542 for a radial shaft seal 58 fitted.

In the from the 3 apparent installation state comes the lag screw 55 with its shaft inside the cylindrical through-hole 531 and with her head in the hole 530 to lie down while using its lower threaded section in the thread 540 the lower bearing shell 54 is screwed.

By appropriate dimensioning of the recess 532 used piston 56 and a corresponding length dimensioning of the lag screws 55 then a compression of the compression spring 57 allows for the depth of engagement of the lag screws 55 can be varied.

Accordingly arises between the two bearing shells 53 . 54 one of the compression springs 57 exerted biasing force, which continues to be ensured by appropriate dimensioning makes is that this biasing force to a spaced holder of the two bearings 53 . 54 from each other leads to the formation of a designated by reference numeral V biasing gap. This biasing gap can in the unloaded state of the illustrated balancing device 5 For example, have 6 mm in height, so that a spring travel of just these 6 mm between the two bearings 53 . 54 is available.

In the installation position shown are the compression springs 57 through the into the recess 542 used radial shaft seal 58 sealed against dirt and the like.

The thus pre-assembled and provided with a biasing gap V balancing devices 5 take care of in the 2 schematically apparent way that when the embossing pressure according to arrows L1, L2 on the pivot bearing 3 the embossing rollers 1 . 2 First, the imprinting pressure applied the back pressure of the springs 57 the balancing devices 5 has to overcome until the desired setting of the embossing gap P is applied. For example, a movement of the two embossing rollers 1 . 2 made about 4 mm to achieve the desired embossing gap. Consequently, the previously between the bearings 53 . 54 set preload gap 4 reduced by these 4 mm, so that a lesser, although still existing biasing gap V between the bearing shells 53 . 54 established. However, here are the springs 57 compressed further and generate an opposing biasing force A, as shown in the 2 Ensures that the bearing clearance in the pivot bearings 3 is shifted against the applied forces for generating the embossing pressure, so that the embossing rollers 1 . 2 no bearing play within the pivot bearings 3 more is available to evade during load changes against the arrows L1, L2.

By using the compensating devices explained above 5 can thus each in a conventional manner with pivot bearings 3 and a gap adjusting device with spindle 40 and adjusting nut 41 or Spaltkeilverstellmitteln equipped device are operated without play and a deflection of the embossing rollers are reliably prevented during load changes.

It is understood that depending on the desired embossing force and by means of the compression springs 57 producible counterforce in any desired ratio to each other by selecting appropriate compression springs 57 can be adjusted.

The balancing devices 5 could with correspondingly long journals 11 . 21 also outside the pivot bearing 3 to be ordered.

The above-described invention can not only be used in new constructions, but it can also be existing devices with embossing rollers 1 . 2 , Rotary bearings 3 and adjusting device 4 by integration of the above-explained compensation devices 5 be retrofitted in a simple manner according to the invention and then operated without play.

Claims (13)

Device for embossing a material web, comprising two embossing rollers ( 1 . 2 ) with roll bales ( 10 . 20 ), between which an embossing gap (P) for the passage of the material web is formed, wherein the embossing rollers ( 1 . 2 ) on both sides of the roll bale ( 10 . 20 ) by means of axial bearing pins ( 11 . 21 ) in pivot bearings ( 3 ) of the device are mounted and adjusting means ( 4 ) are provided by means of which the axial distance between the pivot bearings ( 3 ) of the embossing rollers ( 1 . 2 ) is variable, so that the embossing gap (P) of the same in its clearance is adjustable, characterized in that at least one compensating device ( 5 ) with two pivot bearings ( 50 . 51 ) is provided, of which a first pivot bearing ( 50 ) on the journal ( 11 ) of the first embossing roll ( 1 ) and a second pivot bearing ( 51 ) on the journal ( 21 ) of the second embossing roll ( 2 ) and between the two pivot bearings ( 50 . 51 ) of the balancing device ( 5 ) Bearing shells ( 53 . 54 ) are arranged, which the respective adjacent pivot bearing ( 50 . 51 ) receive at least partially and a biasing means for generating a biasing force (A) is provided by means of which the bearing shells ( 53 . 54 ) are spaced apart to form a biasing gap (V) spaced apart. Apparatus according to claim 1, characterized in that the biasing means at least one compression spring ( 57 ) between the bearing shells ( 53 . 54 ) is arranged and at least one lag screw ( 55 ) for biasing the at least one compression spring ( 57 ) between both bearing shells ( 53 . 54 ) is provided. Apparatus according to claim 2, characterized in that the compression spring ( 57 ) in a bore ( 541 ) of a bearing shell ( 54 ) is arranged. Device according to claim 2 or 3, characterized in that a piston ( 56 ) is provided, which is connected to the compression spring ( 57 ) lying in a receiving bore ( 532 ) of the bearing shell ( 53 ) is used. Device according to claim 4, characterized in that the piston ( 56 ) in the hole ( 541 ) of the bearing shell ( 54 ) and by means of a sealing ring ( 58 ) against the bearing shell ( 54 ) is sealed. Device according to one of claims 2 to 5, characterized in that the lag screw ( 55 ) coaxial with compression spring ( 57 ) and pistons ( 56 ) is arranged. Device according to one of claims 2 to 6, characterized in that compression springs ( 57 ) are used with linear or progressive spring characteristic. Device according to one of claims 2 to 7, characterized in that the compression springs ( 57 ) are formed by coil springs or cup spring packages. Device according to one of claims 1 to 6, characterized in that the bearing shells ( 53 . 54 ) unilaterally a collar ( 533 . 543 ) for lateral guidance of the pivot bearing ( 50 . 51 ) exhibit. Device according to one of claims 1 to 7, characterized in that the compensating device ( 5 ) between the roll bales ( 10 . 20 ) and the pivot bearings ( 3 ) of the embossing rollers ( 1 . 2 ) is arranged. Device according to one of claims 1 to 10, characterized in that the pivot bearing ( 50 . 51 ) of the balancing device ( 5 ) are designed as deep groove ball bearings. Device according to one of claims 1 to 11, characterized in that on both sides of the roll barrel ( 10 . 20 ) one compensating device each ( 5 ) is provided. Device according to one of claims 1 to 12, characterized in that the adjusting means ( 4 ) a Spaltinstellkeil or a spindle ( 40 ) with adjusting nut ( 41 ).